Patent Publication Number: US-2023149720-A1

Title: Intracardiac energy harvesting device and implantable electronic medical device

Description:
BACKGROUND OF THE PRESENT INVENTION 
     Field of Invention 
     The present invention relates to the field of medical instruments, in particular to an intracardiac energy harvesting device and an implantable electronic medical device. 
     Description of Related Arts 
     With the continuous development of medical technology, the increasing number of miniature implantable electronic medical devices meeting various disease diagnosis and detection can be met. Implantable pulse generators such as cardiac pacemaker, brain pacemaker and the like are widely used in the field of medical diagnosis and treatment. However, almost all implantable medical devices are powered by an energy storage medium such as a battery, and the lithium battery is used as a current most mature power supply to be applied to clinic, but still has a non-avoidance defect-battery capacity, so that the service life of the implantable electronic medical device is affected; and when the electric quantity of the storage medium is reduced and the implanted medical device cannot work normally or stops working, the life health of the patient is seriously harmed. At present, the problems are mainly solved through periodic device replacement procedures, which not only needs expensive medical expenses, but also needs to bear large surgical risks. 
     In order to solve the problem, in the prior art, some biological mechanical energy of the surface of a biological organ is acquired through an energy harvesting technology, and the biological mechanical energy is converted into electric energy to realize the self-energizing mode of the electronic device. For example, a piezoelectric nanogenerator with a nano-piezoelectric material or a surface of a biological organ such as a diaphragm and a heart is attached to the surface of a biological organ such as a diaphragm and a heart through a sliding triboelectric nanogenerator, so that the nano-piezoelectric material is deformed, or the two friction layers of the sliding triboelectric nanogenerator are relatively sliding, so that electric energy is converted into electric energy. 
     In the process of implementing the embodiment of the present invention, the inventor finds at least the following defects in the prior art: 
     A piezoelectric nanogenerator or a sliding triboelectric nanogenerator and the like are adopted to collect biological mechanical energy on the surface of the biological organ. The biological mechanical energy collection mode is adopted in the surface of the heart. In clinical practice, power generation components such as the piezoelectric nanogenerator or the sliding triboelectric nanogenerator need to be sewn and attached to the pericardial outer membrane, so that the normal physiological function of the heart can be influenced by the damage of the piezoelectric nanogenerator or the sliding triboelectric nanogenerator, and the piezoelectric nanogenerator or the sliding triboelectric nanogenerator and other power generation components need to be connected with external electronic medical devices such as a pulse emitter through a wire, so that the infection probability is increased. Therefore, the method for collecting the biological mechanical energy on the surface of the biological organ needs to be implanted through a large incision operation, the clinical application has great difficulty, the damage to the organism is large, and the method does not have an actual application prospect. 
     In addition, the cardiac pacemaker currently applied clinically consists of a pacing lead implanted in the heart and a pulse generator buried under the chest of the chest, pulse current is generated through the pulse generator, the pulse generator is conducted to the heart through the pacing lead, and the pulse generator buried under the chest of the chest is used for driving or guiding the surface of the organ or tissue such as the heart, the diaphragm muscle, the lung and the like to collect the biological mechanical energy, that is, the harvesting part is relatively fixed, so that the structure or material of the power generation part is improved, and the problem is avoided. 
     SUMMARY OF THE PRESENT INVENTION 
     The main purpose of the embodiment of the present invention is to provide an intracardiac energy harvesting device and an implantable electronic medical device, so as to solve the technical problem that in the prior art, a large wound operation needs to be adopted to implant a power generation unit on the surface of a heart to cause damage to the heart and easy infection of the organism in the prior art. 
     In order to achieve the above object, according to one aspect of the present invention, an intracardiac energy harvesting device is provided, comprising: a fixing mechanism arranged on the shell, which is configured to fix the shell to an interior of a heart chamber to enable the shell to move along with beating of heart; a nanogenerator module packaged in the shell, which is configured to output electrical energy in response to movement of the shell as the heart beats; and a power management module packaged in the shell, which is used for managing the electric energy output by the nanogenerator module. 
     According to another aspect of the present invention, an intracardiac energy harvesting device implantation method is provided, wherein the above intracardiac energy harvesting device is adopted. The implantation method comprises steps of: implanting the intracardiac energy harvesting device into a heart chamber by an interventional procedure; and fixing the intracardiac energy harvesting device on a cardiac tissue by a fixing mechanism. 
     According to yet another aspect of the present invention, an implantable electronic medical device is provided, which comprises: an intracardiac energy harvesting device; and a load functional unit electrically connected to an output end of a power management module of the intracardiac energy harvesting device, wherein the intracardiac energy harvesting device is configured to provide electrical energy for the load function unit. 
     The one or more technical solutions provided in the embodiments of the present invention at least have the following technical effects or advantages: 
     According to the intracardiac energy collecting device provided by the present invention, the nanogenerator module and the power management module are packaged in the shell, and a fixing mechanism is arranged on the shell to form an energy collecting device in the heart. The device is suitable for being implanted into the heart chamber through the interventional operation, so that the intracardiac energy collecting device can be implanted into the heart to collect the biological mechanical energy generated by heart beating, the surgical trauma is small, damage to the heart cannot be caused, and infection can be effectively avoided. Therefore, the technical problem that in the prior art, an implantable electronic medical device is self-powered, a large wound operation needs to be adopted to implant a power generation unit on the surface of the heart, so that the heart is damaged and the organism is prone to infection is solved. 
     Due to the adoption of the fixing mechanism, the shell is fixed in the heart chamber, and the inner energy collecting device is driven to move integrally through contraction and relaxation of the heart, so that the internal nanogenerator module can be converted into electric energy in response to the movement and output to the power management module for management, the technical problem of limited bottleneck-battery life of the implantable electronic medical device can be achieved, the technical problem that the existing implantable electronic medical device energy supply technology bottleneck-battery life is limited and the existing cardiac pacemaker with the electrode wire and the capsule bag is large in size and low in integration degree can be solved, and continuous diagnosis and treatment can be achieved through minimally invasive surgery implantation. 
     According to the intracardiac energy harvesting device provided by the present invention, the nanogenerator module and the power management module are packaged in the shell, and a fixing mechanism is arranged on the shell to form an energy collecting device in the heart. The device adopts the device with the size and shape suitable for being implanted into the heart chamber through the interventional operation, the overall quality is light, the structure is centralized, energy collection can be realized, normal physiological functions of the heart are not affected, and the burden on the heart is small. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of an intracardiac energy harvesting device, in accordance with some embodiments; 
         FIG.  2    is a perspective view of an intracardiac energy harvesting device having a helical fixation mechanism modified from  FIG.  1   ; 
         FIG.  3    is a working schematic diagram of the intracardiac energy harvesting device in  FIG.  1    being fixed inside a heart chamber; 
         FIG.  4    is a schematic diagram of a functional module of the intracardiac energy harvesting device according to some embodiments; 
         FIG.  5    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  6    is a schematic structural diagram of a power generation unit in  FIG.  5   ; 
         FIG.  7    is a schematic structural diagram of an intracardiac energy harvesting device having a plurality of power generation units modified from  FIG.  1   ; 
         FIG.  8    is a schematic structural diagram of an intracardiac energy harvesting device having a plurality of power generation units modified from  FIG.  1   ; 
         FIG.  9    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  10    is a schematic structural diagram of the power generation unit in  FIG.  9   ; 
         FIG.  11    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  12    is a schematic structural diagram of an intracardiac energy harvesting device modified from  FIG.  11   ; 
         FIG.  13    is a schematic structural diagram of an intracardiac energy harvesting device modified from  FIG.  11   ; 
         FIG.  14    is a schematic structural diagram of an intracardiac energy harvesting device modified from  FIG.  11   ; 
         FIG.  15    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  16    is a schematic structural diagram of an intracardiac energy harvesting device modified from  FIG.  15   ; 
         FIG.  17    is a schematic structural diagram of an intracardiac energy harvesting device modified from  FIG.  15   ; 
         FIG.  18    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  19    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  20    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  21    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  22    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  23    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  24    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  25    is a schematic structural diagram of a movable body, a sixth electrode layer, and a sixth friction layer in  FIG.  24   ; 
         FIG.  26    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments; 
         FIG.  27    is a schematic structural diagram of the movable body, the sixth electrode layer, and the sixth friction layer in  FIG.  26   ; 
         FIG.  28    is a schematic structural diagram of an implantable electronic medical device in accordance with some embodiments; 
         FIG.  29    is a schematic structural diagram of an implantable electronic medical device in accordance with some embodiments; and 
         FIG.  30    is a functional block diagram of the implantable electronic medical device of  FIG.  29   . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments. 
     It should be noted that, unless otherwise specified, all technical and scientific terms used in the present application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. 
     In the present invention, the terms such as “upper and lower” used in the present invention are generally in the direction shown in the drawings, or for vertical, vertical or gravity directions; for ease of understanding and description, “left and right” are generally left and right as shown in the drawings; “inner and outer” refers to the inner and outer sides of the contour relative to each component itself, but the above-mentioned words are not intended to limit the present invention. 
     In addition, descriptions relating to “first”, “second” and the like in the present disclosure are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, features defined with “first” and “second” may explicitly or implicitly include at least one of the features. In the description of the present invention, “a plurality of” means at least two, for example, two, three, and the like, unless specifically defined otherwise. 
     When used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of” when preceding a list of elements modifies the entire list of elements rather than modifying individual elements in the column. In order to solve the technical problem in the prior art that an implantable electronic medical device is self-powered, a large wound operation needs to be adopted to implant a power generation unit on the surface of a heart, so that the heart is damaged and the organism is easy to infect, and the present invention provides an intracardiac energy harvesting device and an implantable electronic medical device. 
     The present invention is further described below with reference to the accompanying drawings. 
     Embodiment 1 
     The present embodiment provides an intracardiac energy harvesting device  100  having a size and shape adapted to be implanted into the interior of a heart chamber by an interventional procedure, the intracardiac energy harvesting device  100  being applied to collecting biological mechanical energy generated by heart beating by an interventional procedure implanted inside the heart chamber. The interventional surgery is an interventional procedure in medicine, is a minimally invasive treatment by using modern science and technology means, can introduce a specially-made catheter, guide wire and other precise instruments into a human body under the guidance of medical image equipment, and performs diagnosis and local treatment on pathological conditions in the body. For example, the intracardiac energy harvesting device  100  can be implanted into the heart chamber through a catheter through a femoral vein puncture. 
       FIG.  1    is a perspective view of an intracardiac energy harvesting device  100 , in accordance with some embodiments.  FIG.  2    is a perspective view of an intracardiac energy harvesting device having a helical fixation mechanism modified from  FIG.  1   . FIG. 
       3  is a working schematic diagram of the intracardiac energy harvesting device in  FIG.  1    being fixed inside the heart chamber. 
     Referring to  FIG.  1    to  FIG.  3   , an intracardiac energy harvesting device  100  includes a shell  10 , a fixing mechanism  20 , a nanogenerator module  30 , and a power management module  40 . 
     The shell  10  is an internally hollow packaging shell for encapsulating the nanogenerator module  30  (or the nanogenerator module  30  and the power management module  40 ) therein, so as to prevent external influence on the nanogenerator module  30  (or the nanogenerator module  30  and the power management module  40 ), and provide a placement environment for the nanogenerator module  30  (or the nanogenerator module  30  and the power management module  40 ). 
     The shell  10  may be exposed to the interior of the heart chamber as a shell  10  in contact with blood in the intracardiac energy harvesting apparatus  100 , so that the shell  10  may include an insulating material with good biocompatibility and good blood compatibility, for example, the shell  10  may include at least one of polylactic acid, polyvinyl alcohol, polytetrafluoroethylene, rubber and a composite material. The shell can be processed and formed by 3D printing or infusion using a mold. 
     An outer diameter of the shell  10  is 5 mm-15 mm, and a length of the shell  10  is 1 cm-5 cm. Within this size range, the shell  10  can be adapted to be implanted inside the heart chamber by means of an interventional procedure, and can be appropriately movable inside the heart chamber, so that the shell  10  can move in the heart chamber as the heart beats. Preferably, the outer diameter of the shell  10  is 7-10 mm, the length of the shell  10  is 2 cm-3 cm, and the energy harvesting device  100  in the heart has a smaller volume. 
     The shell  10  has a cylindrical shape, a prism shape, and an irregular cylindrical or prismatic shape (for example, one end is an arc surface, and one end thereof is a cylindrical or prismatic shape with an arc surface), but is not limited thereto, so that the shell  10  can have a small size in the radial direction (the width direction) and have a relatively small size in the axial direction (the length direction), so that the shell  10  can have a smaller size in the radial direction (the width direction) and have a certain volume in the radial direction (the width direction) to encapsulate the nanogenerator module  30  and the power management module  40 , thereby not affecting the output of the nanogenerator module  30 . Preferably, the shell  10  is cylindrical. If the outer shell  10  is spherical, the outer diameter of the spherical shell can only be below 7 mm due to interventional operation implantation, so that the size of the spherical shell is small, and the output of the nanogenerator module  30  is not facilitated. Of course, the shell  10  may also be in other shapes other than the cylindrical shape. 
     The fixing mechanism  20  is disposed on the shell  10 , the fixing mechanism  20  may be fixed to the outside of the shell  10 , and the fixing mechanism  20  is configured to fix the shell  10  inside the heart chamber to enable the shell  10  to move along with the beating of the heart. After the intracardiac energy harvesting device  100  is implanted inside the heart chamber by means of an interventional procedure, the shell  10  is fixed inside the heart chamber by means of the fixing mechanism  20 , for example, may be fixed on an endocardial and/or myocardial layer of the heart. When the heart beats, the energy harvesting device  100  in the heart can be driven to move, so that the nanogenerator module  30  can convert the electric energy into electric energy and transmit the electric energy to the power management module  40  in response to the movement. 
     The securing mechanism  20  may be disposed at an end or side of the shell  10 . Preferably, the fixing mechanism  20  is disposed at the end of the shell  10 , so that one end of the shell  10  in the length direction thereof is connected to the inner wall of the heart, so that the shell  10  is adapted to the internal space shape of the heart chamber without affecting the contraction and relaxation of the heart, but also facilitates the movement of the shell  10  along the length direction of the shell  10  along with the contraction and relaxation of the heart, thereby facilitating the output of the nanogenerator module  30 . 
     The heart inner energy collecting device  100  can be fixed to the inner wall of the left ventricle of the heart through the fixing mechanism  20 , the position close to the heart tip is fixed to the position, the relative fluctuation amplitude and intensity of the heart are larger, the motion amplitude and intensity of the energy collecting device  100  in the heart are larger, and therefore the output of the nanogenerator module  30  is facilitated. Of course, the fixed position of the intracardiac energy harvesting device  100  in the heart chamber is not limited thereto. 
     The fixing mechanism  20  is selected form a group consisting of a claw-shaped fixing mechanism, a hook-shaped fixing mechanism, a spiral fixing mechanism and a screw fixing mechanism, but is not limited thereto. Based on the motivation, a person skilled in the art may further adopt other structures of fixing mechanisms.  FIG.  1    shows an example of a fixing mechanism  20  using a claw-shaped fixing mechanism, and  FIG.  2    shows an example of using a spiral fixing mechanism for the fixing mechanism  20 . 
     The nanogenerator module  30  is packaged in the shell  10 , and the nanogenerator module  30  is configured to output electrical energy in response to the movement of the shell  10  with the heart beat, that is, the nanogenerator module  30  can convert the motion of the shell  10  with the heart beat into electrical energy. The length of the nanogenerator module  30  is 0.5 cm to 4.5 cm. Preferably, the length of the nanogenerator module  30  is 1.5 cm. 
     The power management module  40  may be packaged in the shell  10 , but is not limited thereto, and optionally, the power management module  40  may be separately packaged outside the shell  10  by means of a packaging material. The power management module  40  is used for managing the electric energy output by the nanogenerator module  30 . When both the power management module  40  and the nanogenerator module  30  are packaged in the shell  10 , the overall integration level of the energy harvesting device  100  in the heart can be improved. The power management module  40  may comprise a rectification module  41  and an energy storage module  42 , wherein the rectification module  41  is used for converting the alternating current output by the nanogenerator module  30  into a direct current, and the energy storage module  42  is used for storing the direct current output by the rectification module  41 . The rectifying module  41  may include a rectifying unit and a filtering unit. The rectifying unit converts the alternating current output by the nanogenerator module  30  into a direct current. For example, a rectifier bridge may be used. The filtering unit converts the pulsating direct current output by the rectifying unit into a relatively stable direct current, and provides the direct current to the energy storage module  42  for storage, for example, the energy storage module  42  may be a rechargeable lithium battery or an energy storage capacitor. The energy storage module  42  may provide electrical energy to a load functional unit, etc., of the implantable electronic medical device for operation thereof. In the interior of the shell  10 , the power management module  40  and the nanogenerator module  30  may be spaced apart by a hard layer, and an output electrode of the nanogenerator module  30  may be electrically connected to an input electrode of the rectifying unit of the power management module  40  by means of a flexible circuit board or a wire. The power output electrode  401  of the power management module  40  can extend to the outside of the shell  10  through a wire to provide electrical energy for the load. The power management module  40  has a length of 0.5 cm to 4.5 cm. Preferably, the length of the power management module  40  is 1 cm. The relative positions of the nanogenerator module  30  and the power management module  40  in the shell  10  are not limited, for example, the nanogenerator module  30  may be located at one end of the shell  10  away from the fixing mechanism  20 , and the nanogenerator module  30  may also be located at one end, close to the fixing mechanism  20 , in the shell  10 .  FIG.  4    is a schematic diagram of a functional module of an energy harvesting device in a heart. 
       FIG.  5    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments. 
     Referring to  FIG.  5   , in the present embodiment, the nanogenerator module  30  includes a first cavity  31 , at least one power generation unit  32 , and at least one first runout body  33 . 
     The first cavity  31  is a cavity inside the shell  10 . 
     The at least one power generation unit  32  is disposed in the first cavity  31 , and the power generation unit  32  may be disposed on at least one of the top wall, the bottom wall and the side wall of the first cavity  31 . The at least one power generation unit  32  is selected from a group consisting of a triboelectric nanogenerator unit and a triboelectric nanogenerator. 
     At least one of the first runout bodies  33  is freely movably disposed in the first cavity  31 , that is, when the heart beats and drives the shell  10  to move through the fixing mechanism  20 , the shell  10  drives the first runout body  33  to move in the first cavity  31 . The first runout body  33  is configured to move in the first cavity  31  and make contact with and/or impact the power generation unit  32  in response to the beating of the heart (i.e., contraction and contraction of the heart), so that the power generation unit  32  outputs an electrical signal to the power management module  40 . The first runout body  33  can be integrally formed, and can also be a multi-layer combined runout body. 
       FIG.  6    is a schematic structural diagram of the power generation unit  32  in  FIG.  5   . 
     Referring to  FIG.  5    and  FIG.  6   , in the present embodiment, the power generation unit  32  is a triboelectric nanogenerator unit, and the power generation unit  32  comprises a first electrode layer  321 , a first friction layer  322 , a second electrode layer  323 , and a second friction layer  324  disposed in contact with the second electrode layer  323 . 
     The first runout body  33  is configured to move between the first friction layer  322  and the second friction layer  324  in response to the beating of the heart, so that the first runout body  33  is in contact with and separated from the first friction layer  322 , and the first runout body  33  is in contact with and separated from the second friction layer  324 , so that the first electrode layer  321  and the second electrode layer  323  output electrical signals to the power management module  40 . The first electrode layer  321  and the second electrode layer  323  may be electrically connected to an input electrode of the rectifying unit of the power management module  40  through the first wire  01 , respectively. The first friction layer  322  and the second friction layer  324  are arranged face to face, and refer to both the first friction layer  322  and the second friction layer  324  being located between the first electrode layer  321  and the second electrode layer  323 . 
     There is a difference between the material of the first friction layer  322  and the material of the outer surface of the first runout body  33 , so that a contact charge can be generated on the surfaces of the first runout body  33  and the first friction layer  322  in a contact or friction process, and the surface of one of the first runout body  33  and the first friction layer  322  is positively charged, and the other surface is negatively charged; the material of the second friction layer  324  is different from the material of the outer surface of the first runout body  33 , so that contact charges can be generated on the surfaces of the first runout body  33  and the second friction layer  324  in a contact or friction process, the surface of one of the first runout body  33  and the second friction layer  324  is positively charged, and the other surface is negatively charged. 
     Each of the first friction layer  322 , the second friction layer  324  and the first runout body  33  is selected from a group consisting of an insulator material, a semiconductor material, and a conductor material. The conventional insulating material has triboelectric characteristics, and can be used as a material for preparing the first friction layer  322 , the second friction layer  324  and the first runout body  33 . Compared with the insulator, the semiconductor and the metal all have frictional electrical properties that are prone to loss of electrons, and therefore, the semiconductor and the metal can also be used as materials for preparing the first friction layer  322 , the second friction layer  324  and the first runout body  33 . In this embodiment, each of the first friction layer  322 , the second friction layer  324  and the first runout body  33  are selected from a group consisting of polyethylene, polypropylene, polystyrene, silica gel, polydimethylsiloxane, polyester, polyurethane, polymethacrylate, polytetrafluoroethylene and nylon, polyimide, nitrile rubber, fluororubber, latex, chitin, cellulose, gold, silver, copper, aluminum, iron and an alloy material, but is not limited thereto. Preferably, both the first friction layer  322  and the second friction layer  324  are polytetrafluoroethylene, and the first runout body  33  is polypropylene. 
     Each of the material of the first electrode layer  321  and the material of the second electrode layer  323  is selected from a group consisting of a metal and a conductive polymer material, wherein the metal is selected from a group consisting of gold, silver, copper, aluminum, iron and an alloy, and the conductive polymer material is selected from a group consisting of carbon nanotubes, graphene and carbon black, but is not limited thereto. Preferably, the material of the first electrode layer  321  and the material of the second electrode layer  323  are both gold. The first electrode layer  321  and the second electrode layer  323  may be coated on the surface of the corresponding friction layer by magnetron sputtering, but are not limited thereto, and the first electrode layer  321  and the second electrode layer  323  may be prepared in other manners. 
     By using the power generation unit  32  of the structure, when the heart beats to drive the shell  10  to move, the first runout body  33  reciprocates between the first friction layer  322  and the second friction layer  324 , so that a potential difference is generated between the first friction layer  322  and the second friction layer  324 . Under the coupling of the friction power and the electrostatic induction effect, the first electrode layer  321  and the second electrode layer  323  generate an electric potential difference, and the alternating electrical signal will continue to be generated in the external circuit, so that the first electrode layer  321  and the second electrode layer  323  continuously output an electrical signal to the power management module  40 . 
     The power generation layer formed by the first electrode layer  321  and the first friction layer  322  is symmetrically arranged with the power generation layer formed by the second electrode layer  323  and the second friction layer  324 , and the materials of the first friction layer  322  and the second friction layer  324  are the same. 
     The first friction layer  322  or the second friction layer  324  may be prepared by replacing an insulating material or a semiconductor material with a conductor material, that is, the first friction layer  322  may be a conductor material, and instead of the first electrode layer  321  in contact therewith, the second friction layer  324  may be a conductor material, and instead of the second electrode layer  323  in contact therewith, the structure of the power generation unit  32  can be simplified, and the manufacturing cost is reduced. The conductor material may be selected from at least one of a metal, a conductive oxide, and a conductive polymer material. 
     At least one of the contact surfaces of the first friction layer  322 , the contact surface of the second friction layer  324 , and the outer surface of the first runout body  33  is selected from a group consisting of a micro-nano structure, a dot conjugate of the nanomaterial, and a coating of the nanomaterial. The micro-nano structure comprises micro-structures on the order of micron or submicron. The micro-structure is selected form a group consisting of nanowires, nanotubes, nanoparticles, nano-trenches, micro-trenches, nano-cones, micrometer cones, nanospheres, and micro-spherical structures, but is not limited thereto. A contact surface of the first friction layer  322  faces a surface of the second friction layer  324 , and a contact surface of the second friction layer  324  faces a surface of the first friction layer  322 . By adopting the arrangement, the contact area between the contact surface of the first friction layer  322  and the outer surface of the first runout body  33  can be increased, so that the contact charge amount is increased, the contact area between the contact surface of the second friction layer  324  and the outer surface of the first runout body  33  can be increased, the contact charge amount is increased, and then the electrical signal output of the first electrode layer  321  and the first electrode layer  321  is facilitated. 
     The first electrode layer  321  and the second electrode layer  323  of the power generation unit  32  are sequentially arranged along the length direction of the shell  10 . In this arrangement, when the shell  10  is fixed to the inner wall of the heart along its length direction and moves along the length direction of the shell  10 , the first runout body  33  moves in the first cavity  31  along the length direction of the shell  10 , and reciprocates between the first friction layer  322  and the second friction layer  324 , thereby facilitating the output of electrical signals between the first electrode layer  321  and the first electrode layer  321 . In this case, the fixing mechanism  20  may be disposed at an end of the shell  10  along the length direction of the shell  10 . When there is only one power generation unit  32  in the first cavity  31 , the first electrode layer  321  and the second electrode layer  323  can be respectively fixed to the top wall and the bottom wall of the first cavity  31  in the length direction of the shell  10 . 
     It should be noted that the position of the first electrode layer  321  and the second electrode layer  323  of the power generation unit  32  in the shell  10  is not limited thereto. Optionally, the first electrode layer  321  and the second electrode layer  323  of the power generation unit  32  are sequentially arranged along the width direction of the shell  10 . In this case, the fixing mechanism  20  may be disposed at the side of the shell  10  along the width direction of the shell  10 . When there is only one power generation unit  32  in the first cavity  31 , the first electrode layer  321  and the second electrode layer  323  can be respectively fixed on the side wall of the first cavity  31  along the length direction of the shell  10 . 
     The first runout body  33  has an outer diameter of 100 μm-5 mm, but is not limited thereto, which facilitates free movement of the first runout body  33  in the first cavity  31 . Preferably, the outer diameter of the first runout body  33  is 2 mm. 
     Two or more first runout bodies  33  can be arranged in the space formed between the first friction layer  322  and the second friction layer  324 , for example, the plurality of first runout bodies  33  can be arranged under the condition that the overall quality of the energy harvesting device  100  in the heart does not affect the normal work of the heart, and the output performance of the power generation unit  32  can be improved. 
     The first runout body  33  may be any one of a polyhedron, a cylinder, a sphere and an ellipsoid, but is not limited thereto. 
       FIG.  7    is a schematic structural diagram of an intracardiac energy harvesting device having a plurality of power generation units modified from  FIG.  1   .  FIG.  8    is a schematic structural diagram of an intracardiac energy harvesting device having a plurality of power generation units modified from  FIG.  1   . 
     Referring to  FIG.  7    and  FIG.  8   , the number of the power generation units  32  may be multiple, the plurality of power generation units  32  are stacked, and each of the space formed between the first friction layer  322  and the second friction layer  324  of each power generation unit  32  moves in respective corresponding spaces, so as to make contact and separation between the first friction layer  322  and the second friction layer  324  of the respective power generation units  32 , so that the first electrode layer  321  and the second electrode layer  323  of each power generation unit  32  output electrical signals to the power management module  40 . The number of the power generation units  32  may be 2-10, preferably, the number of the power generation units  32  is  3 . By adopting the arrangement, the current output performance of the nanogenerator module  30  can be effectively improved. 
     The plurality of power generation units  32  are sequentially stacked along the length direction of the shell  10 , and the first electrode layer  321  and the second electrode layer  323  of each power generation unit  32  are sequentially arranged along the length direction of the shell  10 . The above arrangement is used to facilitate the placement of the plurality of power generation units  32  in the shell  10 . 
     The power management module  40  may include at least one rectification unit corresponding to the number of power generation units  32 , each power generation unit  32  is connected to a rectifying unit, and the output ends of all the rectifying units are connected in parallel. By adopting the arrangement, the overall current output of the nanogenerator module  30  can be improved. 
     The two adjacent power generation units  32  can be separated by a separation layer, so that each power generation unit  32  is connected in parallel after respective rectification after each power generation unit  32  is subjected to power generation. The electrode layer of the power generation unit  32  is disposed on the inner wall of the first cavity  31  or the separation layer.  FIG.  7    shows an example of a plurality of power generation units  32  separated by a separation layer between two adjacent power generation units  32 . It should be noted that the two adjacent power generation units  32  can share the same electrode layer, and each electrode layer is coupled together through a diode, so that when the potential distribution between any two electrode layers changes, current output can be formed in the external circuit.  FIG.  8    shows an example of a plurality of power generation units  32  sharing the same electrode layer between two adjacent power generation units  32 . 
     Embodiment 2 
     The present embodiment provides an intracardiac energy harvesting device  100  having a size and shape adapted to be implanted into the interior of a heart chamber by an interventional procedure. The intracardiac energy harvesting device  100  comprises a shell  10 , a fixing mechanism  20 , a nanogenerator module  30 , and a power management module  40 . 
     The nanogenerator module  30  comprises a first cavity  31 , at least one power generation unit  32 , and at least one first runout body  33 . 
     The first cavity  31  is a cavity inside the shell  10 . 
     The at least one power generation unit  32  is disposed in the first cavity  31 , and the power generation unit  32  may be disposed on at least one of the top wall, the bottom wall and the side wall of the first cavity  31 . The at least one power generation unit  32  is selected from a group consisting of a triboelectric nanogenerator unit and a triboelectric nanogenerator. 
     At least one of the first runout bodies  33  is freely movably disposed in the first cavity  31 , that is, when the heart beats and drives the shell  10  to move through the fixing mechanism  20 , the shell  10  drives the first runout body  33  to move in the first cavity  31 . The first runout body  33  is configured to move in the first cavity  31  and make contact with and/or impact the power generation unit  32  in response to the beating of the heart (i.e., contraction and contraction of the heart), so that the power generation unit  32  outputs an electrical signal to the power management module  40 . The first runout body  33  can be integrally formed, and can also be a multi-layer combined runout body. 
     In embodiment 1, the power generation unit  32  includes a first electrode layer  321 , a first friction layer  322  disposed in contact with the first electrode layer  321 , a second electrode layer  323 , and a second friction layer  324  disposed in contact with the second electrode layer  323 . 
       FIG.  9    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments.  FIG.  11    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments. 
     Embodiment 2 differs from Embodiment 1 in that: 
     Referring to  FIGS.  9  and  11   , the power generation unit  32  is a triboelectric nanogenerator unit, and the power generation unit  32  includes a third electrode layer  325 , a third friction layer  326  in contact with the third electrode layer  325 , a fourth electrode layer  327 , and a fourth friction layer  328  disposed in contact with the fourth electrode layer  327 . 
     The third friction layer  326  and the fourth friction layer  328  are arranged face to face and are spaced apart from each other, and the first runout body  33  is configured to move in the first cavity  31  in response to the beating of the heart and apply a force to the third friction layer  326  and/or the fourth friction layer  328 , so that the third friction layer  326  and the fourth friction layer  328  are in contact and separated, so that the third electrode layer  325  and the fourth electrode layer  327  output electrical signals to the power management module  40 . The third electrode layer  325  and the fourth electrode layer  327  may be electrically connected to the input electrodes of the rectifying unit of the power management module  40  through the second wire  02 , respectively. The third friction layer  326  and the fourth friction layer  328  are arranged face to face, and refer to both the third friction layer  326  and the fourth friction layer  328  being located between the third electrode layer  325  and the fourth electrode layer  327 . 
     There is a difference in electronic capacity between the material of the third friction layer  326  and the material of the fourth friction layer  328 , so that the contact surfaces of the third friction layer  326  and the fourth friction layer  328  contact or rub, so that contact charges can be generated on the contact surfaces of the third friction layer  326  and the fourth friction layer  328 , one of the contact surfaces is positively charged, and the other contact surface is negatively charged. Each of the third friction layer  326  and the fourth friction layer  328  is selected from a group consisting of an insulator material, a semiconductor material, and a conductor material. The conventional insulating material has triboelectric characteristics and can be used as a material for preparing the third friction layer  326  and the fourth friction layer  328 . Relative to the insulator, both the semiconductor and the metal have frictional electrical properties that tend to lose electrons, and thus, the semiconductor and metal can also be used as a material for the preparation of the third and fourth friction layers  326 ,  328 . In this embodiment, each of the third friction layer  326  and the fourth friction layer  328  is selected from a group consisting of polyethylene, polypropylene, polystyrene, silica gel, polydimethylsiloxane, polyester, polyurethane, polymethacrylate, polytetrafluoroethylene and nylon, polyimide, nitrile rubber, fluororubber, latex, chitin, cellulose, gold, silver, copper, aluminum, iron and an alloy material, but is not limited thereto. 
     Each of the materials of the third electrode layer  325  and the material of the fourth electrode layer  327  is selected from a group consisting of a metal and a conductive polymer material, wherein the metal is selected from a group consisting of gold, silver, copper, aluminum, iron and an alloy, but is not limited thereto, and the conductive polymer material is selected from a group consisting of carbon nanotubes, graphene and carbon black, but is not limited thereto. 
     The third friction layer  326  or the fourth friction layer  328  may be prepared by replacing an insulating material or a semiconductor material with a conductor material, that is, the third friction layer  326  may be a conductor material, and instead of the third electrode layer  325  disposed in contact therewith, the fourth friction layer  328  may be a conductor material, and instead of the fourth electrode layer  327  disposed in contact therewith, the structure of the power generation unit  32  can be simplified, and the manufacturing cost is reduced. The conductor material may be selected from at least one of a metal, a conductive oxide, and a conductive polymer material. 
     At least one of the contact surfaces of the third friction layer  326  and the contact surface of the fourth friction layer  328  is selected from a group consisting of a micro-nano structure, a dot conjugate of the nanomaterial, and a coating of the nanomaterial. The micro-nano structure comprises micro-structures on the order of micron or submicron. The micro-structure is selected from a group consisting of nanowires, nanotubes, nanoparticles, nano-trenches, micro-trenches, nano-cones, micrometer cones, nanospheres, and micro-spherical structures, but is not limited thereto. A contact surface of the third friction layer  326  faces a surface of the fourth friction layer  328 , and a contact surface of the fourth friction layer  328  faces a surface of the third friction layer  326 . By adopting the arrangement, the contact area between the contact surface of the third friction layer  326  and the contact surface of the fourth friction layer  328  can be increased, so that the contact charge amount is increased, and the electrical signal output of the third electrode layer  325  and the fourth electrode layer  327  is facilitated. 
     A surface of the third electrode layer  325  away from the third friction layer  326  may be provided with a third substrate  3250 , and/or a surface of the fourth electrode layer  327  away from the fourth friction layer  328  may be provided with a fourth substrate  3270 , and when the first runout body  33  moves in the first cavity  31 , contact and separation between the third friction layer  326  and the fourth friction layer  328  are caused by impacting the third substrate  3250  and/or the fourth substrate  3270 , so that the third electrode layer  325  and the fourth electrode layer  327  output electrical signals to the power management module  40 . 
     The third electrode layer  325  may be directly fixed on the inner wall of the first cavity  31  or fixed to the inner wall of the first cavity  31  through the third substrate  3250 . The inner wall of the first cavity  31  is selected from a group consisting of a top wall, a bottom wall and a side wall of the first cavity  31 . At this time, when the first runout body  33  moves in the first cavity  31 , the third friction layer  326  and the fourth friction layer  328  are in contact and separated by impacting the fourth substrate  3270 . Between the inner wall of the first cavity  31  and the fourth substrate  3270 , between the inner wall of the first cavity  31  and the fourth substrate  3270 , between the third substrate  3250  and the fourth substrate  3270 , at least one of the third substrate  3250  and the fourth substrate  3270 , between the third substrate  3250  and the fourth substrate  3270 , at least one of the third friction layer  326  and the fourth friction layer  328  may be provided with at least one support member  320 , and the third friction layer  326  and the fourth friction layer  328  are supported by the support member  320  so that the third friction layer  326  and the fourth friction layer  328  are spaced apart from each other by a certain space. The support  320  may be an elastic support or a non-elastic support. When the supporting piece  320  is an elastic supporting piece, the supporting piece  320  can be a spring. However, the support  320  is not limited thereto and may include various other resilient members. When the first runout body  33  moves in the first cavity  31 , the support member  320  is subjected to force compression by impacting the fourth substrate  3270 , thereby making contact and separation between the third friction layer  326  and the fourth friction layer  328 . At least one of the third substrate  3250  and the fourth substrate  3270  may have a flexible material that is flexible to return to its initial state as the impact force of the first runout body  33  is removed, or at least one of the third substrate  3250  and the fourth substrate  3270  may include a material having flexibility to deform to extend or contract due to external forces. For example, at least one of the third substrate  3250  and the fourth substrate  3270  may include polyester (PE), polyethersulfone (PES), polyethylene naphthalate (PEN), or polyimide (PI), but is not limited thereto. The third electrode layer  325  and the third friction layer  326  may have flexibility and stretchability corresponding to the third substrate  3250 , and the fourth electrode layer  327  and the fourth friction layer  328  may have flexibility and stretchability corresponding to the fourth substrate  3270 . 
     The fourth electrode layer  327  may be directly fixed on the inner wall of the first cavity  31  or fixed to the inner wall of the first cavity  31  through the fourth substrate  3270 . The inner wall of the first cavity  31  is selected from a group consisting of a top wall, a bottom wall and a side wall of the first cavity  31 . At this time, when the first runout body  33  moves in the first cavity  31 , that is, the third substrate  3250  is impacted, so that the third friction layer  326  and the fourth friction layer  328  are in contact and separated. Between the inner wall of the first cavity  31  and the third substrate  3250 , between the inner wall of the first cavity  31  and the third substrate  3250 , between the fourth substrate  3270  and the third substrate  3250 , at least one of the fourth substrate  3270  and the third substrate  3250 , at least one of the fourth friction layer  328  and the third substrate  3250 , the fourth friction layer  328  and the third friction layer  326  may be provided with at least one support member  320 , and the third friction layer  326  and the fourth friction layer  328  are spaced apart from each other by means of the support member  320 . When the first runout body  33  moves in the first cavity  31 , the support member  320  is subjected to force compression by impacting the third substrate  3250 , thereby making contact and separation between the third friction layer  326  and the fourth friction layer  328 . At least one of the third substrate  3250  and the fourth substrate  3270  may have a flexible material that is flexible to return to its initial state as the impact force of the first runout body  33  is removed, or at least one of the third substrate  3250  and the fourth substrate  3270  may include a material having flexibility to deform to extend or contract due to external forces. 
       FIG.  12    is a schematic structural diagram of an intracardiac energy harvesting device modified from  FIG.  11   . 
     Referring to  FIG.  12   , the outer edge of the third substrate  3250  and the outer edge of the fourth substrate  3270  may be both fixed on the side wall of the first cavity  31 , so that space is formed on both sides of the power generation unit  32 , the first runout body  33  located on one side of the third substrate  3250  impacts the third substrate  3250  during movement, and the first runout body  33  located on one side of the fourth substrate  3270  impacts the fourth substrate  3270  during movement, thereby making contact and separation between the third friction layer  326  and the fourth friction layer  328 . At this point, each of the third substrate  3250  and the fourth substrate  3270  may include a material that is flexible to return to its initial state as the impact force of the first runout body  33  is removed, or each of the third and fourth substrates  3250 ,  3270  may include a material having flexibility to deform to extend or contract due to impact forces of the first runout body  33 . The third electrode layer  325  and the third friction layer  326  may have flexibility and stretchability corresponding to the third substrate  3250 , and the fourth electrode layer  327  and the fourth friction layer  328  may have flexibility and stretchability corresponding to the fourth substrate  3270 . When the third substrate  3250  and the fourth substrate  3270  are in a natural state, the third substrate  3250  and the fourth substrate  3270  may be arc-shaped or arched. 
     Referring to  FIG.  9    and  FIG.  11   , the number of the power generation units  32  is multiple, the two adjacent power generation units  32  are spaced apart by a space for free movement of the at least one first runout body  33 , and when the shell  10  moves along with the heart beat, the third substrate  3250  and/or the fourth substrate  3270  of each power generation unit  32  are impacted by the first runout body  33 , so that the third electrode layer  325  and the fourth electrode layer  327  of each power generation unit  32  output electrical signals to the rectifier unit of the power management module  40 . 
     The power management module  40  may include at least one rectification unit corresponding to the number of power generation units  32 , each power generation unit  32  is connected to a rectifying unit, and the output ends of all the rectifying units are connected in parallel. By adopting the arrangement, the overall current output of the nanogenerator module  30  can be improved. 
       FIG.  13    is a schematic structural diagram of an intracardiac energy harvesting device modified from  FIG.  11   . 
     Referring to  FIG.  13   , the plurality of power generation units  32  may be stacked, and the two adjacent power generation units  32  may be separated from each other by means of a third substrate  3250  and/or a fourth substrate  3270 , so that each power generation unit  32  is separately connected to a rectification unit, and the output ends of all the rectification units are connected in parallel. 
       FIG.  14    is a schematic structural diagram of an intracardiac energy harvesting device modified from  FIG.  11   . 
     Referring to  FIG.  14   , it should be noted that the third substrate  3250  and/or the fourth substrate  3270  may not be disposed between two adjacent power generation units  32 , and the same electrode layer may be shared between two adjacent power generation units  32 . 
     Embodiment 3 
     The present embodiment provides an intracardiac energy harvesting device  100  having a size and shape adapted to be implanted into the interior of a heart chamber by an interventional procedure. The intracardiac energy harvesting device  100  comprises a shell  10 , a fixing mechanism  20 , a nanogenerator module  30 , and a power management module  40 . 
     The nanogenerator module  30  comprises a first cavity  31 , at least one power generation unit  32  and at least one first runout body  33 . 
     The first cavity  31  is a cavity inside the shell  10 . 
     The at least one power generation unit  32  is disposed in the first cavity  31 , and the power generation unit  32  may be disposed on at least one of the top wall, the bottom wall and the side wall of the first cavity  31 . The at least one power generation unit  32  is selected from a group consisting of a triboelectric nanogenerator unit and a triboelectric nanogenerator. 
     At least one of the first runout bodies  33  is freely movably disposed in the first cavity  31 , that is, when the heart beats and drives the shell  10  to move through the fixing mechanism  20 , the shell  10  drives the first runout body  33  to move in the first cavity  31 . The first runout body  33  is configured to move in the first cavity  31  and make contact with and/or impact the power generation unit  32  in response to the beating of the heart (i.e., contraction and contraction of the heart), so that the power generation unit  32  outputs an electrical signal to the power management module  40 . The first runout body  33  can be integrally formed, and can also be a multi-layer combined runout body. 
     In embodiment 1, the power generation unit  32  includes a first electrode layer  321 , a first friction layer  322  disposed in contact with the first electrode layer  321 , a second electrode layer  323 , and a second friction layer  324  disposed in contact with the second electrode layer  323 . 
       FIG.  15    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments. 
     Embodiment 3 differs from Embodiment 1 in that: 
     Referring to  FIG.  15   , the power generation unit  32  is a triboelectric nanogenerator , the power generation unit  32  comprises a piezoelectric material layer  3201 , a first piezoelectric electrode layer  3202  disposed in contact with the piezoelectric material layer  3201  and located on one side of the piezoelectric material layer  3201 , and a second piezoelectric electrode layer  3203  disposed in contact with the piezoelectric material layer  3201  and located on the other side of the piezoelectric material layer  3201 . 
     The first runout body  33  is configured to move in the first cavity  31  in response to the beating of the heart and apply a force to the piezoelectric material layer  3201 , so that the first piezoelectric electrode layer  3202  and the second piezoelectric electrode layer  3203  output electrical signals to the power management module  40 . The first piezoelectric electrode layer  3202  and the second piezoelectric electrode layer  3203  may be electrically connected to an input electrode of a rectifying unit of the power management module  40  through a third wire, respectively. 
     Each of the first piezoelectric electrode layer  3202  and the second piezoelectric electrode layer  3203  is selected from a group consisting of a metal conductor material, a metal alloy conductor material, a metal oxide conductor material (e.g., indium oxide), but is not limited thereto. 
     The piezoelectric material layer  3201  is selected from a group consisting of a piezoelectric ceramic, an oxide, and a polymer, for example, the piezoelectric material layer  3201  is selected from a group consisting of lead zirconate titanate (PZT), zinc oxide and polyvinylidene fluoride (PVDF), but is not limited thereto. The piezoelectric polarization direction of the triboelectric nanogenerator can be up and down, which is not limited herein. 
     A surface of the first piezoelectric electrode layer  3202  away from the piezoelectric material layer  3201  may be provided with a first substrate  3204 , and a surface of the second piezoelectric electrode layer  3203  away from the piezoelectric material layer  3201  may be provided with a second substrate  3205 . 
     The first piezoelectric electrode layer  3202  can be directly fixed on the inner wall of the first cavity  31  or fixed to the inner wall of the first cavity  31  through the first substrate  3204 . When the first bouncing body  33  moves in the first cavity  31 , the piezoelectric material layer  3201  is stressed to deform by impacting the second substrate  3205 , so that a potential difference is generated on the upper surface and the lower surface of the piezoelectric material layer  3201 , opposite charges are induced on the surface of the first piezoelectric electrode layer  3202  and the second piezoelectric electrode layer  3203 , and the electric energy is output to the rectifying unit of the power management module  40  under the condition that the external circuit is switched on. 
     The second piezoelectric electrode layer  3203  may be directly fixed on the inner wall of the first cavity  31  or fixed to the inner wall of the first cavity  31  by means of the second substrate  3205 . When the first bouncing body  33  moves in the first cavity  31 , the piezoelectric material layer  3201  is stressed to deform by impacting the first substrate  3204 , so that a potential difference is generated on the upper surface and the lower surface of the piezoelectric material layer  3201 , opposite charges are induced on the surface of the first piezoelectric electrode layer  3202  and the second piezoelectric electrode layer  3203 , and the electric energy is output to the rectifying unit of the power management module  40  under the condition that the external circuit is switched on. 
       FIG.  16    is a schematic structural diagram of an intracardiac energy harvesting device modified from  FIG.  15   . 
     Referring to  FIG.  16   , the outer edge of the first substrate  3204  and the outer edge of the second substrate  3205  may be both fixed on the side wall of the first cavity  31 , so that the two sides of the power generation unit  32  both form a space, the first runout body  33  located on one side of the first substrate  3204  impacts the first substrate  3204 , and the first runout body  33  located on one side of the second substrate  3205  impacts the second substrate  3205  when moving, so that the first piezoelectric electrode layer  3202  and the second piezoelectric electrode layer  3203  output electrical energy to the rectifier unit of the power management module  40 . 
     Each of the first substrate  3204  and the second substrate  3205  may be a flexible material or a non-flexible material. At least one of the first substrate  3204  and the second substrate  3205  may include a material having flexibility to deform to extend or contract due to impact forces of the first runout body  33 . 
     It should be noted that the structure of the triboelectric nanogenerator is merely an example, and in practice, the specific structure of the triboelectric nanogenerator is not limited in this embodiment, that is, the triboelectric nanogenerator of any structure can be applied to the structure of the intracardiac energy harvesting device  100  according to the present embodiment. 
     As shown in  FIG.  15    and  FIG.  16   , the number of the power generation units  32  is multiple, the adjacent two power generation units  32  are spaced apart by a space allowing the at least one first runout body  33  to move freely, and when the shell  10  moves along with the heart beat, the first runout body  33  impacts the first substrate  3204  and/or the second substrate  3205  of each power generation unit  32 , so that the piezoelectric material layer  3201  of each power generation unit  32  is stressed to deform, and the first piezoelectric electrode layer  3202  and the second piezoelectric electrode layer  3203  of each power generation unit  32  output electrical energy to the rectifier unit of the power management module  40 . 
     The power management module  40  may include at least one rectification unit corresponding to the number of power generation units  32 , each power generation unit  32  is connected to a rectifying unit, and the output ends of all the rectifying units are connected in parallel. By adopting the arrangement, the overall current output of the nanogenerator module  30  can be improved. 
     The plurality of power generation units  32  may be stacked, and the two adjacent power generation units  32  may be separated from each other by means of the first substrate  3204  and/or the second substrate  3205 , so that each power generation unit  32  is separately connected to a rectifying unit, and the output ends of all the rectifying units are connected in parallel. It should be noted that the first substrate  3204  and/or the second substrate  3205  may not be disposed between two adjacent power generation units  32 , and the same piezoelectric electrode layer may be shared.  FIG.  17    shows an example of sharing the same piezoelectric electrode layer between two adjacent power generation units  32 . 
     Embodiment 4 
     The present embodiment provides an intracardiac energy harvesting device  100  having a size and shape adapted to be implanted into the interior of a heart chamber by an interventional procedure. The intracardiac energy harvesting device  100  comprises a shell  10 , a fixing mechanism  20 , a nanogenerator module  30 , and a power management module  40 . 
     The nanogenerator module  30  comprises a first cavity  31 , at least one power generation unit  32  and at least one first runout body  33 . 
     The first cavity  31  is a cavity inside the shell  10 . 
     The at least one power generation unit  32  is disposed in the first cavity  31 , and the power generation unit  32  may be disposed on at least one of the top wall, the bottom wall and the side wall of the first cavity  31 . The at least one power generation unit  32  is selected from a group consisting of a triboelectric nanogenerator unit and a triboelectric nanogenerator. 
     At least one of the first runout bodies  33  is freely movably disposed in the first cavity  31 , that is, when the heart beats and drives the shell  10  to move through the fixing mechanism  20 , the shell  10  drives the first runout body  33  to move in the first cavity  31 . The first runout body  33  is configured to move in the first cavity  31  and make contact with and/or impact the power generation unit  32  in response to the beating of the heart (i.e., contraction and contraction of the heart), so that the power generation unit  32  outputs an electrical signal to the power management module  40 . The first runout body  33  can be integrally formed, and can also be a multi-layer combined runout body. 
     In embodiment 1, the power generation unit  32  includes a first electrode layer  321 , a first friction layer  322  disposed in contact with the first electrode layer  321 , a second electrode layer  323 , and a second friction layer  324  disposed in contact with the second electrode layer  323 . 
       FIGS.  18 - 20    is a schematic structural diagram of an intracardiac energy harvesting device according to some embodiments. 
     Embodiment 4 differs from Embodiment 1 in that: 
     Referring to  FIGS.  18 - 20   , at least two power generation units  32  are arranged in the first cavity  31 , and the at least two power generation units  32  comprise at least one triboelectric nanogenerator unit and at least one triboelectric nanogenerator. 
     The first runout body  33  is configured to contact and/or impact the triboelectric nanogenerator unit and/or the triboelectric nanogenerator in response to the beating of the heart, so that the triboelectric nanogenerator unit and/or the triboelectric nanogenerator output an electrical signal to the power management module  40 , respectively. 
     The at least one triboelectric nanogenerator unit is selected from a group consisting of the triboelectric nanogenerator unit in Embodiment 1 and the triboelectric nanogenerator unit in Embodiment 2.  FIG.  18    shows an example of a triboelectric nanogenerator unit in Embodiment 1.  FIG.  19    and  FIG.  20    illustrate an example of using the triboelectric nanogenerator unit in Embodiment 2. The at least one triboelectric nanogenerator can be the triboelectric nanogenerator in Embodiment 3. 
     At least one triboelectric nanogenerator unit and at least one triboelectric nanogenerator can be spaced apart from each other by a space for free movement of at least one first runout body  33 , and the triboelectric nanogenerator unit and the triboelectric nanogenerator are repeatedly contacted and/or hit by moving the first runout body  33  in the space, so that the triboelectric nanogenerator unit and the triboelectric nanogenerator output electrical signals to the power management module  40 , respectively. 
     The at least one triboelectric nanogenerator unit and the at least one triboelectric nanogenerator can be stacked, and the adjacent triboelectric nanogenerator units and the triboelectric nanogenerator s can be separated through the substrate, so that each triboelectric nanogenerator unit and each triboelectric nanogenerator are separately connected with a rectification unit, and the output ends of all the rectification units are connected in parallel.  FIG.  18    shows an example of an adjacent triboelectric nanogenerator unit and a triboelectric nanogenerator separated by a substrate. It should be noted that the adjacent triboelectric nanogenerator unit and the triboelectric nanogenerator can also not be provided with a substrate, and the adjacent triboelectric nanogenerator unit and the triboelectric nanogenerator can share the same electrode layer. 
     Embodiment 5 
     The present embodiment provides an intracardiac energy harvesting device  100  having a size and shape adapted to be implanted into the interior of a heart chamber by an interventional procedure. The intracardiac energy harvesting device  100  comprises a shell  10 , a fixing mechanism  20 , a nanogenerator module  30 , and a power management module  40 . 
     In Embodiment 1, the nanogenerator module  30  comprises a first cavity  31 , at least one power generation unit  32 , and at least one first runout body  33 , wherein the first runout body  33  is configured to move in the first cavity  31  and contact and/or impact the power generation unit  32  in response to the beating of the heart, so that the power generation unit  32  outputs an electrical signal to the power management module  40 . 
       FIG.  21    to  FIG.  23    are schematic structural diagrams of an intracardiac energy harvesting device according to some embodiments. 
     Embodiment 5 differs from Embodiment 1 in that: 
     Referring to  FIGS.  21  - 23   , the nanogenerator module  30  includes a second cavity  34 , at least one triboelectric nanogenerator unit, and/or at least one triboelectric nanogenerator, at least one second runout body  35 , and at least one coil  36 . 
     The second cavity  34  is a cavity inside the shell  10 . 
     The at least one triboelectric nanogenerator unit and/or the at least one triboelectric nanogenerator are both disposed in the second cavity  34 , and the at least one triboelectric nanogenerator unit is selected from a group consisting of the triboelectric nanogenerator unit in Embodiment 1 and the triboelectric nanogenerator unit in Embodiment 2.  FIG.  21    shows an example of a triboelectric nanogenerator unit in Embodiment 1.  FIG.  22    shows an example of a triboelectric nanogenerator unit in Embodiment 2. The at least one triboelectric nanogenerator can be the triboelectric nanogenerator in Embodiment 3.  FIG.  22    shows an example of a triboelectric nanogenerator in Embodiment 3. 
     At least one second runout body  35  is freely movably disposed in the second cavity  34 , that is, when the heart beats and drives the shell  10  to move through the fixing mechanism  20 , the shell  10  drives the second runout body  35  to move in the second cavity  34 . Moreover, the second runout body  35  includes a magnet to cause the second runout body  35  to generate an alternating magnetic field during movement of the second cavity  34 . The second runout body  35  may be a magnet as a whole. When at least one triboelectric nanogenerator unit comprises the triboelectric nanogenerator unit in Embodiment 1, the second runout body  35  may comprise a magnet and a friction material provided on the outer surface of the magnet, and the friction material may be a material of the first runout body  33  in Embodiment 1. The magnet is selected from a group consisting of neodymium iron boron, aluminum nickel cobalt, samarium cobalt and ferrite. 
     At least one coil  36  is fixed in the second cavity  34 , at least one coil  36  can be fixed on the inner wall of the second cavity  34 , and the inner wall of the second cavity  34  is selected from a group consisting of a top wall, a bottom wall and a side wall of the first cavity  31 . The coil  36  is used for relatively cutting the magnetic induction lines in the alternating magnetic field generated by the movement of the second runout body  35  in the second cavity  34 , so that alternating current is generated in the coil  36 , and a magnetoelectric potential difference is formed. Two ends of the coil  36  may be electrically connected to an input electrode of the rectifying unit of the power management module  40  through a fourth wire, respectively. The coil  36  may be a planar coil, and the coil  36  may be a single-phase or concentric-winding annular coil. 
     The second runout body  35  is configured to move in the second cavity  34  in response to the runout of the heart to make contact and/or impact the triboelectric nanogenerator  32  and/or the triboelectric nanogenerator  32  and generate an alternating magnetic field, so that the triboelectric nanogenerator  32  and/or the triboelectric nanogenerator  32  outputs an electrical signal to the power management module  40 , and outputs a magnetic electrical signal to the power management module  40  relative to the magnetic induction line in the alternating magnetic field. 
     By means of the arrangement, the shell  10  moves along with the beating of the heart, thereby driving the second runout body  35  to move in the second cavity  34 , that is, the triboelectric nanogenerator  32  and/or the triboelectric nanogenerator  32  can output current in response to the contact and/or impact of the second runout body  35 , thereby effectively improving the output performance and the energy conversion efficiency of the nanogenerator module  30 . 
     Embodiment 6 
     The present embodiment provides an intracardiac energy harvesting device  100  having a size and shape adapted to be implanted into the interior of a heart chamber by an interventional procedure. The intracardiac energy harvesting device  100  comprises a shell  10 , a fixing mechanism  20 , a nanogenerator module  30 , and a power management module  40 . 
     In Embodiment 1, the nanogenerator module  30  comprises a first cavity  31 , at least one power generation unit  32 , and at least one first runout body  33 , wherein the first runout body  33  is configured to move in the first cavity  31  and contact and/or impact the power generation unit  32  in response to the beating of the heart, so that the power generation unit  32  outputs an electrical signal to the power management module  40 . 
       FIG.  24    and  FIG.  26    are schematic structural diagrams of an intracardiac energy harvesting device according to some embodiments. 
     Embodiment 6 differs from Embodiment 1 in that: 
     Referring to  FIGS.  24  and  26   , the nanogenerator module  30  includes a third cavity  301 , a movable body  302 , a sixth electrode layer  303 , and a sixth friction layer  304 . 
     The third cavity  301  is a cavity inside the shell  10 . 
     The movable body  302  is movably disposed in the third cavity  301 , that is, when the heart beats and drives the shell  10  to move through the fixing mechanism  20 , the shell  10  drives the movable body  302  to move in the third cavity  301 . The movable body  302  includes a fifth electrode layer  3021 , and a fifth friction layer  3022  in contact with the fifth electrode layer  3021 , and the fifth friction layer  3022  is disposed on a surface of the fifth electrode layer  3021  close to the sixth friction layer  304 . The movable body  302  may further include a core body  3023 , so that the fifth electrode layer  3021  is disposed on the core body  3023 , and the fifth friction layer  3022  is disposed on the fifth electrode layer  3021 . 
     The sixth electrode layer  303  is disposed in the third cavity  301 , and the sixth electrode layer  303  and the fifth electrode layer  3021  are spaced apart from each other. The sixth electrode layer  303  may be disposed on at least one of a top wall, a bottom wall and a side wall of the third cavity  301 .  FIG.  24    shows an example of a sixth electrode layer  303  disposed on a top wall and a bottom wall of a third cavity  301 .  FIG.  26    shows an example of a sixth electrode layer  303  disposed on a sidewall of the third cavity  301 . The fifth electrode layer  3021  and the sixth electrode layer  303  may be electrically connected to an input electrode of the rectifying unit of the power management module  40  through a fifth wire, respectively. It should be noted that the length of the wire connected to the fifth electrode layer  3021  needs to be appropriate and should not limit the free movement of the movable body  302  in the third cavity  301 . 
     The sixth friction layer  304  is disposed in contact with the sixth electrode layer  303 , and the sixth friction layer  304  is disposed on a surface of the sixth electrode layer  303  close to the fifth friction layer  3022 . 
     The movable body  302  is configured to make contact and separation between the fifth friction layer  3022  and the sixth friction layer  304  in response to the beating of the heart, so that the fifth electrode layer  3021  and the sixth electrode layer  303  output electrical signals to the power management module  40 . 
     There is a difference in electronic capacity between the material of the fifth friction layer  3022  and the material of the sixth friction layer  304 , so that the surface of the fifth friction layer  3022  and the sixth friction layer  304  can generate contact charges on the surfaces of the fifth friction layer  3022  and the sixth friction layer  304 , and the contact surface of one of the fifth friction layer  3022  and the sixth friction layer  304  is positively charged, and the other contact surface is negatively charged. 
     Each of the material of the fifth friction layer  3022  and the material of the sixth friction layer  304  is selected from a group consisting of an insulator material, a semiconductor material, and a conductor material. The conventional insulating material has triboelectric characteristics and can be used as a material for preparing the fifth friction layer  3022  and the sixth friction layer  304 . Relative to the insulator, both the semiconductor and the metal have frictional electrical properties that are prone to loss of electrons, and therefore, the semiconductor and metal can also be used as a material for preparing the fifth and sixth friction layers  3022 ,  304 . In the present embodiment, each of the fifth friction layer  3022  and the sixth friction layer  304  is selected from a group consisting of polyethylene, polypropylene, polystyrene, silica gel, polydimethylsiloxane, polyester, polyurethane, polymethacrylate, polytetrafluoroethylene and nylon, polyimide, nitrile rubber, fluororubber, latex, chitin, cellulose, gold, silver, copper, aluminum, iron and an alloy material, but is not limited thereto. 
     Each of the material of the fifth electrode layer  3021  and the material of the sixth electrode layer  303  is selected from a group consisting of a metal and a conductive polymer material, wherein the metal is selected from a group consisting of gold, silver, copper, aluminum, iron and an alloy, and the conductive polymer material is selected from a group consisting of carbon nanotubes, graphene and carbon black, but is not limited thereto. 
     The shell  10  is driven by the fixing mechanism  20  to move, and the shell  10  drives the movable body  302  to move in the third cavity  301  (when the sixth friction layer  304  is disposed along the side wall of the third cavity  301 , the fifth friction layer  3022  and the sixth friction layer  304  may be in contact with and separated from each other, and when the sixth friction layer  304  is disposed on the top wall or the bottom wall of the third cavity  301 , contact occurs between the fifth friction layer  3022  and the sixth friction layer  304 . and so that a potential difference is generated between the fifth electrode layer  3021  and the sixth electrode layer  303  under the coupling of the friction power and the electrostatic induction effect; an alternating electrical signal is generated in the external circuit; along with continuous contraction and relaxation of the heart, the alternating current electric signal continuously generates, so that the fifth electrode layer  3021  and the sixth electrode layer  303  continuously output an electrical signal to the power management module  40 . 
     The shape of the movable body  302  is not limited, for example, the fifth friction layer  3022  and the fifth electrode layer  3021  may be enclosed cylindrical or spherical or non-closed curved surfaces or planes, but are not limited thereto. The shape of the sixth friction layer  304  and the sixth electrode layer  303  is not limited, and the sixth friction layer  304  and the sixth electrode layer  303  may be cylindrical or non-closed curved surfaces or planes enclosed along the inner side wall of the third cavity  301 , but are not limited thereto.  FIG.  26    shows an example in which the sixth friction layer  304  and the sixth electrode layer  303  enclose a cylindrical shape along the inner side wall of the third cavity  301 . 
     The fifth friction layer  3022  and the sixth friction layer  304  may be prepared by replacing an insulating material or a semiconductor material with a conductor material, that is, the fifth friction layer  3022  may be a conductor material, and instead of the fifth electrode layer  3021  disposed in contact therewith, the sixth friction layer  304  may be a conductor material, and instead of the sixth electrode layer  303  disposed in contact therewith, the conductor material may be selected from at least one of a metal, a conductive oxide, and a conductive polymer material. 
     At least one of the contact surfaces of the fifth friction layer  3022  and the contact surface of the sixth friction layer  304  is selected from a group consisting of a micro-nano structure, a dot conjugate of the nanomaterial, and a coating of the nanomaterial. The micro-nano structure comprises micro-structures on the order of micron or submicron. The micro-structure is selected from a group consisting of nanowires, nanotubes, nanoparticles, nano-trenches, micro-trenches, nano-cones, micrometer cones, nanospheres, and micro-spherical structures, but is not limited thereto. A contact surface of the fifth friction layer  3022  faces a surface of the sixth friction layer  304 , and a contact surface of the sixth friction layer  304  faces a surface of the fifth friction layer  3022 . 
     Embodiment 7 
     The embodiment of the present invention provides an implantation method of an inner energy harvesting device in a heart. The intracardiac energy harvesting device is any one of the heart internal energy harvesting devices  100  in any one of the above embodiments, and the implantation method of the intracardiac energy harvesting device comprises the following steps. 
     The intracardiac energy harvesting device  100  is implanted inside the heart chamber through an interventional procedure, for example, the intracardiac energy harvesting device  100  can be implanted into the heart chamber through a catheter, and certainly, the puncture part and the delivery component are not limited thereto. 
     The intracardiac energy harvesting device  100  is fixed to the heart tissue by means of a fixing mechanism  20  thereof. 
     Embodiment 8 
       FIG.  28    is a schematic structural diagram of an implantable electronic medical device, in accordance with some embodiments. 
     Referring to  FIG.  28   , the present embodiment provides an implantable electronic medical device. The implantable electronic medical device comprises an intracardiac energy harvesting device  100  and a load function unit  200 . 
     The intracardiac energy harvesting device  100  may be any one of the above embodiments 1-6. The intracardiac energy harvesting device  100  has a size and shape suitable for implantation into the heart chamber by means of an interventional operation. 
     The intracardiac energy harvesting device  100  is configured to acquire biomechanical energy generated by systolic and diastolic of the heart by means of being fixed inside the heart chamber, and convert it into electrical energy, thereby providing electrical energy for the load function unit  200 . 
     The load function unit  200  is a set functional unit of the implantable electronic medical device, so as to play a role in treating and/or detecting an organism, but the function is not limited thereto. The load function unit is electrically connected with the output end of the power management module  40  of the energy harvesting device in the heart, and the intracardiac energy harvesting device  100  is used for providing electric energy for the load function unit. The load function unit  200  is selected from a group consisting of a functional unit of the leadless cardiac pacemaker, a functional unit of the heart monitoring hemodynamic sensor, and a functional unit of the vascular robot, but is not limited thereto, so long as the electronic medical device which needs to consume electric energy for the treatment, diagnosis or detection of the organism is included in the organism. 
       FIG.  29    is a schematic structural diagram of an implantable electronic medical device in accordance with some embodiments. 
     Referring to  FIG.  29   , the load function unit  200  may be integrated with the intracardiac energy harvesting device  100 . The integration degree of the implantable electronic medical device is improved, and the volume is reduced. 
       FIG.  30    is a functional block diagram of the implantable electronic medical device of  FIG.  29   . 
     Referring to  FIG.  30   , the implantable electronic medical device may be a leadless cardiac pacemaker, and at this time, the load function unit  200  includes a heart rate sensing portion  210 , a pulse emitting portion  220 , and an electrode portion  230 ,  FIG.  29    illustrates an example of an implantable electronic medical device being a leadless cardiac pacemaker. 
     The heart rate sensing portion  210  is configured to sense a heart rate, and the heart rate sensing portion  210  may detect the beating state of the heart by means of the electrode portion  230 . The heart rate sensing portion  210  may be electrically connected to an output end of the power management module  40  of the intracardiac energy harvesting device  100 . The heart rate sensing portion  210  may be disposed inside the shell  10 . 
     The pulse emitting portion  220  is configured to emit an electrical pulse in response to a heart rate sensed by the heart rate sensing portion. The pulse emitting portion  220  may be electrically connected to the heart rate sensing portion  210 , and when the heart rate sensing portion  210  senses that the heart rate is low (for example, the heart rate sensing portion  210  perceives that the heart rate is lower than a preset threshold), the pulse emitting portion  220  may generate a pulse current and conduct the pulse current to the heart tissue through the electrode portion  230  to stimulate heart beat. The pulse emitting portion  220  may be disposed inside the shell  10 . 
     The electrode portion  230  is configured to contact the heart tissue to conduct a heart rate sensing signal to the heart rate sensing portion and to conduct an electrical pulse occurring at the pulse emitting portion to the heart. The electrode portion  230  may be electrically connected to the heart rate sensing portion  210  and/or the pulse emitting portion  220 . The electrode portion  230  may include two or more electrodes disposed within, on, or near the shell, for example, the electrode portion  230  may include a first electrode and a second electrode, the first electrode and the second electrode may be metal conductors exposed on a sidewall of the shell  10 , and the first electrode and the second electrode are insulated from each other on the shell  10 . At least one electrode of the electrode portion  230  may be disposed on a portion of the shell  10  close to the fixing mechanism  20 , so that when the fixing mechanism  20  fixes the shell  10  on the cardiac tissue, at least one electrode of the electrode portion  230  contacts the heart tissue. 
     The power management module  40 , the heart rate sensing portion  210 , the pulse emitting portion  220 , and the electrode portion  230  may be sequentially connected by means of a wire or a flexible circuit board, and the portions may be isolated from each other in addition to a wire or a flexible circuit. 
     The nanogenerator module  30 , the power management module  40 , the heart rate sensing portion  210 , the pulse emitting portion  220 , and the electrode portion  230  may be sequentially disposed along the length direction of the shell  10 , and the electrode portion  230  may be located at one end close to the fixing mechanism  20 , but is not limited thereto. The nanogenerator module  30 , the power management module  40 , the heart rate sensing portion  210 , and the pulse emitting portion  220  may be adjusted in a placement position in the shell  10 . 
     In the overall volume of the shell  10 , the volume of the nanogenerator module  30  may account for ⅓, the power management module  40  may occupy a ratio of ⅙, the heart rate sensing portion  210  and the pulse emitting portion  220  may occupy 0.5-2 mm in diameter, and preferably, the diameter of the electrode portion  230  is 0.8 mm. 
     It can be seen from the above that according to the implantable electronic medical device provided by the embodiment of the present invention, biological mechanical energy generated by cardiac contraction and diastole is collected in the heart chamber through the inner energy harvesting device  100  in the heart, and the mechanical energy is converted into electric energy, so that normal work of the implantable electronic medical device is guaranteed, so that the self-powered implantable electronic medical device is realized, and the technical problem that a bottleneck-battery life of an existing implantable electronic medical device is limited is solved.; the surgical wound is small, damage to the heart is avoided, infection can be effectively avoided, long-term stable power supply can be carried out on the load function unit of the implantable electronic medical device, the technical problem that the existing implantable electronic medical device energy supply technology bottleneck-battery life is limited is solved, the technical problem that the existing implantable electronic medical device energy supply technology bottleneck-battery life is limited is solved, long-term stability can be achieved, and continuous diagnosis and treatment can be achieved through minimally invasive surgery implantation. 
     The above are only specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto, and any changes or substitutions which do not involve an inventive effort shall fall within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope defined in the claims.