PATENT DOCUMENT

Publication Number: US-11417926-B2
Application Number: US-201916354382-A
Country: US
Kind Code: B2

Title: Feedthroughs for thin battery cells

Abstract:
The disclosed technology relates to electrical feedthroughs for thin battery cells. A battery cell enclosure includes a terraced portion having a reduced thickness relative to another portion of the enclosure. The enclosure includes an opening disposed on a horizontal surface of the terraced portion for receiving the electrical feedthrough. Because the feedthrough is disposed on the horizontal surface of the terraced portion, the feedthrough may be over-sized thereby reducing the resistance and impedance of the feedthrough without increasing the height or thickness of the enclosure.

Claims:
What is claimed is: 
     
       1. A battery cell, comprising:
 a set of layers comprising a cathode layer, an anode layer, and a separator layer disposed between the cathode layer and the anode layer; 
 an enclosure enclosing the set of layers, the enclosure comprising a terraced portion having a reduced thickness relative to another portion of the enclosure, the enclosure further comprising an opening disposed at the terraced portion, the opening having a feedthrough that passes therethrough, the feedthrough comprising:
 an annular channel comprising an outer ring, an inner sidewall, and a base; an insulator formed of glass, the insulator bonded to the inner sidewall of the annular channel; and 
 a pin extending through the insulator, the pin electrically coupled to a tab extending from the set of layers to form an external battery terminal at the pin. 
 
 
     
     
       2. The battery cell of  claim 1 , wherein the outer ring of the annular channel is welded to the enclosure along a periphery of the opening. 
     
     
       3. The battery cell of  claim 1 , further comprising a second insulator disposed on an inner surface of the enclosure and proximate to the tab to prevent electrical contact between the tab and the inner surface of the enclosure. 
     
     
       4. The battery cell of  claim 1 , wherein the insulator is further bonded to the base of the annular channel, the insulator further comprising an overmold portion that extends between the base of the annular channel and the tab, the overmold portion configured to prevent electrical contact between the tab and the annular channel. 
     
     
       5. The battery cell of  claim 1 , further comprising a dielectric spacer disposed between the base of the annular channel and the tab, the dielectric spacer configured to prevent electrical contact between the tab and the annular channel. 
     
     
       6. The battery cell of  claim 1 , wherein the enclosure has a thickness less than 3 mm. 
     
     
       7. The battery cell of  claim 1 , wherein the enclosure has a non-rectangular shape. 
     
     
       8. The battery cell of  claim 1 , wherein the enclosure further comprises a flange extending along a periphery of the enclosure, wherein the flange comprises a lip extending from the flange, the lip configured to stiffen the enclosure. 
     
     
       9. The battery cell of  claim 1 , wherein the enclosure further comprises a flange extending along a periphery of the enclosure, wherein the flange comprises mounting holes.

Description:
PRIORITY 
     This application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application Ser. No. 62/772,790, entitled “FEEDTHROUGHS FOR THIN BATTERY CELLS,” filed on Nov. 29, 2018, which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to battery cell feedthroughs, and more particularly, to battery cell feedthroughs for use with thin battery cells. 
     BACKGROUND 
     Lithium-ion batteries are used in various portable electronic devices, including laptop computers, tablet computers, mobile phones, personal digital assistants (PDAs), digital music players, watches, and wearable devices. 
     One important aspect of lithium-ion batteries is the electrical feedthrough which enables electrical connection, through the battery enclosure, to the electrode stack. Electrical feedthroughs must insulate the electrical connection to the cathode from the enclosure to prevent shorting of the battery cells. Further, the enclosure enclosing the electrodes may be filled with electrolyte thereby requiring the electrical feedthrough to provide a hermetically seal. 
     SUMMARY 
     The disclosed embodiments provide for a battery cell feedthrough for use in thin battery cells. The feedthrough is provided at a terraced region of an enclosure, where the terraced portion has a reduced thickness relative to other portions of the enclosure. The enclosure encloses a set of layers that include a cathode layer, an anode layer, and a separator layer disposed between the cathode layer and the anode layer. The feedthrough may include an annular channel, an insulator, and a pin. The annular channel may have an outer ring, an inner sidewall, and a base. The insulator may be formed of glass and may be bonded to the inner sidewall of the annular channel. The pin may extend through the insulator and may be electrically coupled to a tab extending from the set of layers to form an external battery terminal at the pin. 
     In some embodiments, a method for manufacturing a battery cell is disclosed. The method includes insulating a pin within an annular channel using glass, sliding the annular channel within an opening disposed on a terraced portion of an enclosure, and welding an outer ring of the annular channel to the enclosure along a periphery of the opening. The method further includes welding a cathode tab extending from a cathode layer to the pin and welding an anode tab extending from an anode layer to the enclosure. The method also includes sealing the enclosure to hermetically seal the cathode and anode layers, and filling the enclosure with electrolyte. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments herein may be better understood by referring to the following description in conjunction with the accompanying drawings in which like reference numerals indicate identical or functionally similar elements. Understanding that these drawings depict only exemplary embodiments of the disclosure and are not therefore to be considered to be limiting of its scope, the principles herein are described and explained with additional specificity and detail through the use of the accompanying drawings in which: 
         FIG. 1  illustrates a perspective view of an assembled battery, in accordance with various aspects of the subject technology; 
         FIG. 2  illustrates a perspective cross-section view of an assembled battery, in accordance with various aspects of the subject technology; 
         FIG. 3A  illustrates a partial-section view of a feedthrough, in accordance with various aspects of the subject technology; 
         FIG. 3B  illustrates a partial-section view of a feedthrough, in accordance with various aspects of the subject technology; 
         FIG. 3C  illustrates a partial-section view of a flange of an enclosure, in accordance with various aspects of the subject technology; 
         FIG. 4  illustrates a perspective view of an assembled battery, in accordance with various aspects of the subject technology; 
         FIG. 5A  illustrates an exploded view of a feedthrough, in accordance with various aspects of the subject technology; 
         FIG. 5B  illustrates an alternative exploded view of a feedthrough, in accordance with various aspects of the subject technology; 
         FIG. 6  illustrates a perspective cross-section view of an assembled battery, in accordance with various aspects of the subject technology; 
         FIG. 7  illustrates a partial-section view of a feedthrough, in accordance with various aspects of the subject technology; 
         FIG. 8  illustrates a perspective view of an assembled battery, in accordance with various aspects of the subject technology; 
         FIG. 9A  illustrates a perspective view of an assembled battery, in accordance with various aspects of the subject technology; 
         FIG. 9B  illustrates a perspective view of an assembled battery, in accordance with various aspects of the subject technology; 
         FIG. 9C  illustrates a perspective view of an assembled battery, in accordance with various aspects of the subject technology; 
         FIG. 10  illustrates a cross-section view of an assembled battery, in accordance with various aspects of the subject technology; 
         FIG. 11  illustrates a portable electronic device, in accordance with various aspects of the subject technology; 
         FIG. 12  illustrates an example method for manufacturing a battery cell, in accordance with various aspects of the subject technology; and 
         FIG. 13  illustrates an example method for manufacturing a battery cell, in accordance with various aspects of the subject technology. 
     
    
    
     DETAILED DESCRIPTION 
     Various embodiments of the disclosure are discussed in detail below. While specific implementations are discussed, it should be understood that this is done for illustration purposes only. A person skilled in the relevant art will recognize that other components and configurations may be used without parting from the spirit and scope of the disclosure. 
     Rechargeable batteries for portable electronic devices often include cells that are made of alternating layers of anode and cathode electrodes, with a separator disposed there-between. The layers may be packaged in an enclosure and may utilize an electrical feedthrough to make an electrical connection to cathode electrodes through the enclosure. The enclosure enclosing the electrodes may be filled with electrolyte thereby requiring the enclosure to be hermetically sealed to prevent unwanted leakage or failure. In addition, electrical feedthroughs must insulate the electrical connection to the cathode electrodes from the enclosure to prevent shorting of the battery cells. 
     Conventionally, feedthroughs may pass through a sidewall, side, or vertical surface of a battery enclosure. Because electrical feedthroughs may require a minimum cross-sectional area to maintain an acceptable level of resistance or impedance, electrical feedthroughs are limited to a certain dimension. As such, a height of a sidewall or thickness of a battery enclosure cannot be reduced beyond the minimal dimension required for the feedthrough. Accordingly, there is a need for certain embodiments of an electrical feedthrough that may be used for thin battery enclosures, such as battery enclosures having a height or thickness of less than 2 mm. 
     The disclosed technology addresses the foregoing limitations of conventional feedthroughs for battery enclosures by positioning a feedthrough at a horizontal surface, as opposed to a vertical surface, and by incorporating a terraced portion on the battery enclosure for receiving the electrical feedthrough. Because the electrical feedthrough is located at the terraced portion with ample physical space for accommodating the feedthrough, the battery cell may have increased performance through use of an over-sized feedthrough, with reduced resistance or impedance, and increased packaging efficiency. 
       FIG. 1  illustrates a perspective view of an assembled battery  100 , in accordance with various aspects of the subject technology. The battery  100  comprises an enclosure  110 , a feedthrough  120 , a terminal  130  and port  140 . The enclosure  110  may comprise a terraced portion  112  having a reduced thickness relative to another portion or remainder of the enclosure  110 . For example, the enclosure  110  may have an overall thickness of less than 3 mm, or more specifically, less than about 2 mm, 1.9 mm, 1.8 mm, 1.7 mm, 1.6 mm, or 1.5 mm, and the terraced portion  112  may have a thickness that is lesser than the overall thickness of the other portions of the enclosure  110 . For example, if the enclosure  110  has an overall thickness of 3 mm, the terraced portion may have a thickness of 1.5 mm. The feedthrough  120  and the terminal  130  may be disposed at the terraced portion  112 . For example, the feedthrough  120  may pass through an opening disposed at the terraced portion and the terminal  130  may be directly welded onto the terraced portion. 
     The enclosure may be formed of metal, such as aluminum or an aluminum alloy, and may have a non-corrosive coating line the interior of the enclosure  110 . The enclosure  110  is configured to enclose and hermetically seal one or more cells disposed within the enclosure. In one aspect, the enclosure  110  may comprise a top portion and a bottom portion. The top portion includes the terraced portion  112  and may comprise a cup or open cube, cuboid, cylinder, prism, cone, pyramid or combination thereof, configured to receive the one or more battery cells. The bottom portion may be configured to completely enclose and seal the one or more battery cells, and may be bonded, glued, welded, mechanically fastened or coupled, to the top portion along a periphery. For example, the top portion and bottom portion of the enclosure  110  may be welded together at the periphery by welding together flanges on the top portion and the bottom portion, respectively. In another example, the top portion and bottom portion of the enclosure  110  may be welded together at a periphery by welding together a joggled overlap between the top portion and the bottom portion. In yet another example, the top portion and bottom portion of the enclosure  110  may be welded together at a periphery by welding together an overlap between the top portion and the bottom portion. 
     Each battery cell may comprise at least one set of layers formed of at least one cathode layer with an active coating, a separator, and at least one anode layer with an active coating, as discussed with reference to  FIG. 10 . A tab may extend from each of the anode and cathode layers, as discussed further below. The terminal  130  may comprise a weld pad that is configured to be electrically connected or coupled to a tab extending from the anode layer. The port  140  may comprise an opening on the enclosure  110  for receiving electrolyte. After the enclosure  110  is sufficiently filled with electrolyte, the port  140  may be welded or sealed shut to prevent leakage of the electrolyte. 
       FIG. 2  illustrates a perspective cross-section view of the assembled battery  100 , in accordance with various aspects of the subject technology. In one aspect, the feedthrough  120  may comprise a pin  122 , an annular channel  124 , and an insulator  126 . The feedthrough  120  seals the set of layers  150  within the enclosure  110  and provides an electrical connection to the anode or cathode layer of the set of layers  150  via the pin  122 . The feedthrough  120  may be disposed at the terraced portion  112  through an opening and bonded, glued, welded, or coupled, to the terraced portion  112  of the enclosure  110 . 
     The annular channel  124  of the feedthrough  120  comprises an outer ring, an inner sidewall, and a base. The outer ring of the annular channel  124  contacts an outer surface of the terraced portion  112  of the enclosure  110 , and after a bonding, gluing, welding, or coupling operation, creates a hermetic seal between the feedthrough  120  and the enclosure  110 . For example, the annular channel  124  may be welded to the opening of the terraced portion  112  along a periphery by welding the outer ring of the annular channel  124  to the outer surface of the terraced portion  112  of the enclosure  110 . The annular channel  124  may be formed of a rigid material, and may further be made of a material that is adequate for welding to the enclosure  110 . For example, if the enclosure  110  is formed of a stainless steel material, the annular channel  124  may also be formed of a stainless steel material to enable welding of the annular channel  124  and enclosure  110 . 
     The insulator  126  is formed of an electrically insulating material, such as glass or a ceramic and prevents electrical contact between the pin  122  and the enclosure  110 . The pin  122  extends through the insulator  126  and is electrically coupled to a tab  160  extending from the set of layers to form an external battery terminal at the pin  122 . The pin may be formed of a metal or alloy, or material that is capable of conducting electricity, such as molybdenum. In one aspect, the pin  122  may be spot welded, laser welded, or ultra-sonic welded to a tab  160  extending from the cathode or anode of the set of layers  150 . When coupled to the tab  160  extending from the set of layers  150 , electrical energy from the cathode or anode, for example, passes through the tab  160  and to the pin  122 , to thereby provide an external terminal for the battery cell  150 . 
     The battery  100  may also include an insulating tape  128  disposed on an inner surface of the enclosure  110  and proximate to the tab  160  to prevent electrical contact between the tab  160  and the inner surface of the enclosure  110 . The insulating tape  128  may have an adhesive on a surface that is in contact with the inner surface of the enclosure  110 , such as pressure sensitive adhesive. 
       FIG. 3A  illustrates a partial-section view of the feedthrough  120  utilizing an overmold portion  127 , in accordance with various aspects of the subject technology. In one aspect, the insulator  126  may further comprise the overmold portion  127  to prevent inadvertent electrical contact between the annular channel  124  and the tab  160 . The insulator  126  may be bonded to the inner sidewall of the annular channel  124  and the base of the annular channel  124 . The insulator  126  is also bonded to the pin  122  and surrounds the pin  122 . The overmold portion  127  of the insulator  126  extends between the base of the annular channel  124  and the tab  160 , thereby preventing electrical contact between the tab  160  and the annular channel  124 . 
       FIG. 3B  illustrates a partial-section view of the feedthrough  120  utilizing a dielectric spacer  129 , in accordance with various aspects of the subject technology. In other aspects, the feedthrough  120  may further comprise the dielectric spacer  129  disposed between the base of the annular channel  124  and the tab  160 . The dielectric spacer  129  is configured to prevent electrical contact between the tab  160  and the annular channel  124 . The dielectric spacer  129  may comprise a ring with a recessed center region for receiving the base of the annular channel  124 . 
       FIG. 3C  illustrates a partial-section view of a flange  115  of the enclosure  110 , in accordance with various aspects of the subject technology. As described above, the top portion and bottom portion of the enclosure  110  may overlap and may be welded together at the periphery of the enclosure  110  to form a flange  115 . In one aspect, the flange  115  may further comprise a lip  116  extending vertically from the flange  115  to stiffen the enclosure  110  by increasing an area moment of inertia for the enclosure. The lip  116  may extend along the entire periphery of the enclosure  110 , or a portion thereof. 
     In some aspects, because the feedthrough  120  is disposed on a horizontal surface of the terraced portion  112 , as opposed to a vertical sidewall of the enclosure  110 , the pin  122  may have a sufficiently large cross-sectional area to ensure that the pin  122  does not throttle or create a bottleneck of the circuit, thereby maintaining the performance of the battery  100 , regardless of the thickness of the enclosure  110 . In other aspects, by disposing the feedthrough  120  onto the horizontal surface of the terraced portion  112 , the pin  122  may be over-sized when compared to conventional feedthroughs, thus increasing the cross-sectional area of the pin  122  and thereby lowering an impedance of the feedthrough  120  by allowing more current to pass through the pin  122 . In another aspect, by disposing the feedthrough  120  onto the horizontal surface of the terraced portion  112 , welding of the annular channel  124  onto the terraced portion  112  becomes easier due to the larger area provided on the terraced portion  112  for welding. In yet another aspect, by disposing the feedthrough  120  onto the horizontal surface of the terraced portion  112 , the dimension of the insulator  126  may be increased radially over conventional feedthroughs, to increase the performance of the insulator  126 . 
       FIG. 4  illustrates a perspective view of an assembled battery  400 , in accordance with various aspects of the subject technology. The battery  400  comprises the enclosure  110 , a feedthrough  420 , the terminal  130  and the port  140 . The enclosure  110  may comprise the terraced portion  112  having a reduced thickness relative to another portion or remainder of the enclosure  110 , as described above. The feedthrough  420  and the terminal  130  may be disposed at the terraced portion  112 . For example, the feedthrough  420  may pass through an opening  412  (as shown in  FIGS. 5A-5B ) disposed at the terraced portion  112  and the terminal  130  may be directly welded onto the terraced portion  112 . 
       FIGS. 5A and 5B  illustrate exploded views of the feedthrough  420 , in accordance with various aspects of the subject technology. The feedthrough  420  may comprise a rivet  421 , an outer gasket  422 , an inner gasket  424 , and a terminal  426 . The rivet  421  is configured to compress the outer gasket  422 , inner gasket  424 , and terminal  426  to create a seal at an opening  412  on a wall of the enclosure  110 . The feedthrough  420  does not require welding to the enclosure because it utilizes a compression force generated by the rivet  421  to create a hermetic seal at the opening  412 . The feedthrough  420  may implement a multitude of anti-rotation features to reduce and mitigate the risk that an electrical short may occur between the feedthrough  420  and the enclosure  110 , as the enclosure  110  may have an anode potential and the feedthrough  420  may have a cathode potential. By mitigating or eliminating the risk of an electrical shortage, reliability of the battery  400  is greatly improved. 
     The rivet  421  may comprise a planar head at a first end, a shank extending therefrom, and a deformable tail at an opposite end. Prior to installation, the deformable tail may have a diameter that is substantially equal to or less than a diameter of the shank extending from the planar head (as shown in  FIGS. 5A and 5B ). The deformable tail of the rivet  421  is configured to expand in diameter after the rivet  421  is installed (as shown in  FIGS. 6 and 7 ), to thereby compress the components sandwiched between the planar head and the deformable tail. In one aspect, the compression force generated by the rivet  421  is sufficient to create a hermetic seal at the opening  412 , as well as prevent undesired rotation of the rivet  421  within the opening  412 , inner gasket  424  within the enclosure  110 , and/or terminal  426 . The compression force generated by the rivet  421  may, for example, cause a compression stress of approximately 10-40 MPa acting on the outer gasket  422  and inner gasket  424 . The rivet  421  may comprise a metal or alloy that is readily deformable, such as an aluminum alloy. 
     The outer gasket  422  may be disposed adjacent to the planar head of the rivet  421 . The outer gasket  422  may comprise a recessed area  501  disposed at a proximal end of the outer gasket  422 , an opening for receiving the shank of the rivet  421 , and a collar  502  disposed at a distal end of the outer gasket  422  surrounding a portion of the opening. The recessed area  501  may be sized to accommodate a portion of the planar head of the rivet  421 . The outer gasket  422  may comprise a polymer, such as perfluoroalkoxy (PFA), or other material capable of insulating electrical energy. In one aspect, the outer gasket  422  surrounds the rivet  421  to electrically insulate the rivet  421  from the enclosure  110 . 
     The inner gasket  424  may be disposed on the collar  502  of the outer gasket  422 . The inner gasket  424  may comprise an opening for receiving the collar of the outer gasket  422 , a protrusion  503  for engaging a corresponding notch  504  on the terminal  426  to prevent rotation of the terminal  426  with respect to the inner gasket  424 , and a recessed portion  505  for seating of the terminal  426  to prevent rotation of the terminal  426  with respect to the inner gasket  424 . The inner gasket  424  may comprise a polymer, such as a pigmented polymer, and may, for example, comprise PFA, or other material capable of insulating electrical energy. In one aspect, the inner gasket  424  electrically insulates the terminal  426  from the enclosure  110 . 
     In one aspect, the protrusion  503  may comprise a step or ledge that is configured to engage a corresponding edge or surface of the terminal  426  to prevent rotation of the terminal  426  with respect to the inner gasket  424 . For example, the step or ledge of the protrusion  503  may mechanically engage and interfere with the edge or surface of the terminal  426  to prevent inadvertently movement or rotation of the terminal  426  about a center axis of the rivet  421 , thereby preventing contact or shorting with an inside surface of the enclosure  110 . 
     In another aspect, the recessed portion  505  may completely or partially surround the terminal  426  to further prevent rotation of the terminal  426  with respect to the inner gasket  424 . For example, the recessed portion  505  may comprise a recessed area surrounded by at least one side wall of the inner gasket  424 . The side wall prevents one or more edges of the terminal  426  from moving or rotating independently from the inner gasket  424  because the side wall surrounding the recessed area mechanically engages and prevents the terminal  426  from inadvertently moving or rotating about a center axis of the rivet  421 , thereby preventing contact or shorting with an inside surface of the enclosure  110 . In one aspect, the side wall may have a drafted profile, as shown in  FIG. 7 . 
     The terminal  426  may be disposed within the recessed portion  505  of the inner gasket  424 . The terminal  426  may include a notch  504  for engaging the protrusion  503  of the inner gasket  424 , and an opening for receiving the shank of the rivet  421 . The terminal  426  may comprise a coupling region for electrically coupling to a tab  160  (show in  FIGS. 6 and 7 ) extending from the set of layers  150  enclosed within the enclosure  110 . The tab  160  extending from the set of layers  150  may, for example, be spot welded to the coupling region. The terminal  426  may comprise a metal or alloy, or material that is capable of conducting electricity. When coupled to the tab  160  extending from the set of layers  150 , electrical energy from the cathode electrodes, for example, passes through the terminal  426  to the rivet  421  to thereby provide an external terminal for the battery cell at the planar head of the rivet  421 . 
     Referring to  FIGS. 6 and 7 , cross-section views of the assembled battery  400  and feedthrough  420  are provided, in accordance with various aspects of the subject technology. The feedthrough  420  seals the set of layers  150  within the enclosure  110  and provides an electrical connection to the anode or cathode layer of the set of layers  150  via the rivet  421 . The terminal  426  is seated within the recess portion of the inner gasket  424 . The inner gasket  424  is disposed within the enclosure  110  and surrounds the collar of the outer gasket  422 . The rivet  421  is shown in a deployed configuration with the deformable tail expanded, thereby compressing the terminal  426 , inner gasket  424 , outer gasket  422 , and terraced portion of the enclosure  110  to create a hermetic seal at the opening of the terraced portion. 
     The battery  400  may also include an insulating tape  128  disposed on an inner surface of the enclosure  110  and proximate to the deformable end of the rivet  421  to prevent electrical contact between the rivet  421  and the inner surface of the enclosure  110 . The insulating tape  128  may have an adhesive on a surface that is in contact with the inner surface of the enclosure  110 , such as pressure sensitive adhesive. 
     In some aspects, because the feedthrough  420  is disposed on a horizontal surface of the terraced portion  112 , as opposed to a vertical sidewall of the enclosure  110 , the rivet  421  may have a sufficiently large cross-sectional area to ensure that the shank of the rivet  421  does not throttle or create a bottleneck of the circuit, thereby maintaining the performance of the battery  400 , regardless of the thickness of the enclosure  110 . The rivet  421  may be over-sized when compared to conventional feedthroughs, thus increasing the cross-sectional area of the rivet  421  and thereby lowering an impedance of the feedthrough  420  by allowing more current to pass through the rivet  421 . In another aspect, by over-sizing the rivet  421 , the compressive force of the rivet  421  is substantially increased thereby improving the mechanical integrity of the feedthrough  420 , as well as the integrity of the hermetic seal generated by the feedthrough  420 . 
       FIG. 8  illustrates a perspective view of an assembled battery  800 , in accordance with various aspects of the subject technology. The battery  800  comprises the enclosure  110 , a first feedthrough  820 , a second feedthrough  830 , and the port  140 . The first and second feedthroughs  820 ,  830  may comprise tabs extending directly from the set of layers  150  enclosed within the enclosure  110 . The tabs of the first and second feedthroughs  820 ,  830  may surrounded by a layer of insulation that prevents electrical contact between the tabs and the enclosure  110 . The insulation may comprise a heat-activated sealing material, such as polypropylene, copolymers of ethylene and acrylic acid, polyamide resins, polyester resins, ionomers, poly urethane resins, polyethylene resin (high as well as low density), nutrient cellophane, actate films, hard and soft vinyl chloride film, polyvinylidene chloride film, polystyrene film, polycarbonate film, nylon film, or polyethylene cellophane. To surround each of the tabs extending from the set of layers  150 , the insulation may be applied to each tab in liquid or gel form and set or cured thereafter. 
     In one aspect, the top or bottom portion of the enclosure may include a relief for each of the feedthroughs  820 ,  830  that allows the feedthroughs  820 ,  830  to extend through the flange  115  of the enclosure  110  without damaging or crimping the tabs of the feedthroughs  820 ,  830 . The relief may comprise an indentation at the flange  115  that is sized to accommodate the tabs of the feedthroughs  820 ,  830 . In one aspect, to create a hermetic seal at the feedthroughs  820 ,  830 , the insulation may be heated so that the insulation bonds directly to the flange  115  using a hot plate, or via impulse bonding, ultra-sonic bonding, high frequency bonding, or hot air bonding. 
     In one aspect, the top portion and/or bottom portion of the enclosure  110  may be lined with a heat-activated sealing material at the flange  115 . Bonding of the top portion of the enclosure  110  with the bottom portion of the enclosure  110  may generate a hermetic seal along the flange  115  and at the feedthroughs  820 ,  830 . To obtain an adequate seal at the flange  115 , the flange may have a minimal width of 2 mm. 
     In some aspects, by simplifying the feedthrough  820 ,  830 , additional components associated with conventional feedthroughs may be eliminated thereby reducing the likelihood of failure, increasing reliability, while also reducing costs. 
       FIGS. 9A-9C  illustrate perspective views of assembled batteries, in accordance with various aspects of the subject technology. Referring to  FIG. 9A , the battery  100  may comprise an enclosure  110 A having a non-rectangular shape. The set of layers  150  or battery cell enclosed within the enclosure may similarly have a non-rectangular shape. As described above, the battery  100  includes the feedthrough  120  and terminal  130  disposed at the terraced portion. The flange  115  of the enclosure  110 A may further comprise mounting holes  117  that are configured to receive hardware for affixing or mounting the battery  100  into a portable device. By utilizing hardware to mount the battery  100  via the mounting holes  117 , the battery  100  may be easily removed from the portable device without use of adhesive or glue. In some aspects, by utilizing hardware to mount the battery  100  to the portable device, use of mounting adhesives are eliminated thereby allowing the battery  100  to increase in thickness and capacity based on the elimination of an adhesive layer. In another aspect, the mounting holes  117  may be formed using a stamping process after welding of the top portion of the enclosure to the bottom portion of the enclosure. 
     Referring to  FIG. 9B , the battery  400  may comprise an enclosure  110 A having a non-rectangular shape. The set of layers  150  or battery cell enclosed within the enclosure may similarly have a non-rectangular shape. As described above, the battery  400  includes the feedthrough  420  and terminal  130  disposed at the terraced portion. The flange  115  of the enclosure  110 A may further comprise mounting holes  117  that are configured to receive hardware for affixing or mounting the battery  400  into a portable device. 
     Referring to  FIG. 9C , the battery  800  may comprise an enclosure  110 A having a non-rectangular shape. The set of layers  150  or battery cell enclosed within the enclosure may similarly have a non-rectangular shape. As described above, the battery  800  includes the first feedthrough  820  and the second feedthrough  830 . The flange  115  of the enclosure  110 A may further comprise mounting holes  117  that are configured to receive hardware for affixing or mounting the battery  800  into a portable device. 
       FIG. 10  illustrates a cross-section view of an assembled battery  1000 , in accordance with various aspects of the subject technology. The assembled battery  1000  includes a battery cell  1050 , enclosure  1010 , a battery management unit  1070 , and battery terminals  1080 . The battery management unit  1070  is configured to manage recharging of the battery cell  1050 . The terminals  1080  are configured to engage with corresponding connectors on a portable electronic device to provide power to components of the portable electronic device. 
     The battery cell  1050  includes a plurality of layers comprising a cathode with an active coating  1050 A, a separator  1052 , and an anode with an active coating  1050 B. For example, the cathode  1050 A may be an aluminum foil coated with a lithium compound (e.g., LiCoO 2 ) and the anode  1050 B may be a copper foil coated with carbon or graphite. The separator  1052  may include polyethylene (PE), polypropylene (PP), and/or a combination of PE and PP, such as PE/PP or PP/PE/PP. The separator  1052  comprises a micro-porous membrane that also provides a “thermal shut down” mechanism. If the battery cell reaches the melting point of these materials, the pores shut down which prevents ion flow through the membrane. 
     The plurality of layers may be wound to form a jelly roll structure or can be stacked to form a stacked-cell structure. The plurality of layers are enclosed within enclosure  1010  and immersed in an electrolyte  1055 , which for example, can be a LiPF6-based electrolyte that can include Ethylene Carbonate (EC), Polypropylene Carbonate (PC), Ethyl Methyl Carbonate (EMC) or DiMethyl Carbonate (DMC). The electrolyte can also include additives such as Vinyl carbonate (VC) or Polyethylene Soltone (PS). The electrolyte can additionally be in the form of a solution or a gel. 
     The cathode layers  1050 A of the plurality of layers are coupled to a tab (not shown) through intermediate tabs (not shown) extending from one or more cathode layers  1050 A. The anode layers  1050 B of the plurality of layers are coupled to a tab  1060  through intermediate tabs  1054  extending from one or more anode layers  1050 B. The tabs extending from the battery cell  1050  provide for electrical connections to other battery cells, the battery management unit  1070 , or other components as desired. As discussed above, the tab  1060  may be electrically coupled to the enclosure  1010  at the terminal  1030 . As also discussed above, the tab extending from the cathode layers may be electrically coupled to the cathode feedthrough (e.g., feedthroughs  120 ,  420 ,  820 ). 
       FIG. 11  illustrates a portable electronic device  1100 , in accordance with various aspects of the subject technology. The above-described rechargeable battery  100 ,  400 ,  800 ,  1000  can generally be used in any type of electronic device. For example,  FIG. 11  illustrates a portable electronic device  1100  which includes a processor  1102 , a memory  1104  and a display  1108 , which are all powered by the battery  1106  (e.g., battery  100 ,  400 ,  800 ,  1000 ). Portable electronic device  1100  may correspond to a laptop computer, tablet computer, mobile phone, personal digital assistant (PDA), digital music player, watch, and wearable device, and/or other type of battery-powered electronic device. Battery  1106  may correspond to a battery pack that includes one or more battery cells. Each battery cell may include a set of layers sealed in an enclosure, including a cathode with an active coating, a separator, an anode with an active coating, and utilize the electrical feedthroughs described above (e.g., feedthroughs  120 ,  420 ,  820 ,  830 ). 
       FIG. 12  illustrates an example method  1200  for manufacturing a battery cell, in accordance with various aspects of the subject technology. It should be understood that, for any process discussed herein, there can be additional, fewer, or alternative steps performed in similar or alternative orders, or in parallel, within the scope of the various embodiments unless otherwise stated. 
     At operation  1210 , a rivet is slid within an opening of an outer gasket. At operation  1220 , the outer gasket is slid within an opening disposed on a terraced portion of an enclosure. As described above, the terraced portion has a reduced thickness with respect to a thickness of another portion of the enclosure. The enclosure is configured to protect a set of layers that comprise a battery cell. The set of layers includes a cathode layer, an anode layer, and a separator layer disposed between the cathode layer and the anode layer. At operation  1230 , an inner gasket is inserted over a collar of the outer gasket and against an inside surface of the enclosure. As described above, the inner gasket includes a recessed portion for receiving a terminal. 
     At operation  1240 , the terminal is seated within the recessed portion of the inner gasket and onto the rivet. At operation  1250 , an end of the rivet is deformed to create a hermetic seal at the opening of the enclosure. In one aspect, to create a hermetic seal at the opening, a compressive force between a head of the rivet and the deformed end of the rivet is generated against the outer gasket, the wall of the enclosure, the inner gasket, and the terminal. 
     At operation  1260 , a cathode tab extending from the cathode layer is welded to the terminal. At operation  1270  an anode tab extending from the anode layer is welded to the enclosure. At operation  1280 , the set of layers are hermetically sealed within the enclosure. At operation  1290 , the enclosure is filled with electrolyte. 
       FIG. 13  illustrates an example method  1300  for manufacturing a battery cell, in accordance with various aspects of the subject technology. It should be understood that, for any process discussed herein, there can be additional, fewer, or alternative steps performed in similar or alternative orders, or in parallel, within the scope of the various embodiments unless otherwise stated. 
     At operation  1310 , a pin is insulated within an annular channel using glass or a ceramic. The pin is configured to conduct electrical energy from a battery cell enclosed within an enclosure to a portable device. At operation  1320 , the annular channel is slid within an opening disposed on a terraced portion of an enclosure. As described above, the terraced portion has a reduced thickness with respect to a thickness of another portion of the enclosure. The enclosure is configured to protect the battery cell. The battery cell includes a cathode layer, an anode layer, and a separator layer disposed between the cathode layer and the anode layer. At operation  1330 , an outer ring of the annular channel is welded to enclosure along a periphery of the opening. 
     At operation  1340 , a cathode tab extending from a cathode layer of the battery cell is welded to the pin. At operation  1350  an anode tab extending from an anode layer of the battery cell is welded to the enclosure. At operation  1360 , the enclosure is hermetically sealed to seal the battery cell within the enclosure. At operation  1370 , the enclosure is filled with electrolyte. 
     Although a variety of examples and other information was used to explain aspects within the scope of the appended claims, no limitation of the claims should be implied based on particular features or arrangements in such examples, as one of ordinary skill would be able to use these examples to derive a wide variety of implementations. Further and although some subject matter may have been described in language specific to examples of structural features and/or method steps, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to these described features or acts. For example, such functionality can be distributed differently or performed in components other than those identified herein. Rather, the described features and steps are disclosed as examples of components of systems and methods within the scope of the appended claims.

Metadata:
Filing Date: 20190315
Publication Date: 20220816
Grant Date: 20220816
Priority Date: 20181129
Inventors: SHIU, BRIAN K.
PASMA, CHRISTOPHER R.
MEYERS, ANDREW
BALARAM, HARAN
Assignee: APPLE INC
CPC Classifications: [{"code": "H01M50/105", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01M50/593", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/562", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/553", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/536", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M10/0525", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01M50/593", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/536", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/553", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/105", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/186", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M10/0587", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/536", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M10/0436", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01M50/562", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/593", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/528", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M10/0585", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/105", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/191", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M2220/30", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01M2220/30", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01M50/562", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M10/0585", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/553", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/543", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01M50/172", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01M50/531", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 70849741