Patent Publication Number: US-2022223752-A1

Title: Method for manufacturing solar cell panel comprising prepreg by means of autoclave

Description:
TECHNICAL FIELD 
     The present disclosure relates to a method of manufacturing a solar cell panel including a prepreg using an autoclave, and more particularly, to a highly rigid and lightweight solar cell panel installable on the top of a vehicle. 
     BACKGROUND ART 
     Recently, various studies have been conducted on alternative energy sources that may replace existing fossil fuels to solve energy problems. In particular, a wide range of studies have been conducted to use natural energy such as wind power and solar power, and a solar cell using solar light is an infinite and eco-friendly resource and thus much attention has been paid thereto as an alternative energy source. 
     The solar cell is a device that converts light energy of the sun into electrical energy and is a key component of a solar power generation system, and for solar power generation, multiple solar cells are connected in series to manufacture a panel type module and such modules are connected to each other in series and parallel. 
     To apply such a solar cell to the field of automobiles, studies have been actively conducted to mount solar cells, and a solar cell panel is mounted on a top surface of the body in the case of some hybrid electric vehicles or electric vehicles (EVs). 
     However, in order to apply a solar cell module to the top of a vehicle, the solar cell panel is manufactured in advance and fixed on the vehicle using a mechanical fixing structure, but in this case, an additional structure should be installed to fixedly install the solar cell module on the vehicle and the weight of the vehicle increases. 
     Therefore, there is a need to develop a method of manufacturing a solar cell panel for solving the problem with installing such a solar cell module and securing an area for installation of the solar cell module to increase efficiency. 
     DISCLOSURE 
     Technical Problem 
     An aspect of the present invention provides a method of manufacturing a lightweight solar cell panel applicable to the top of a vehicle without installing an additional fixing structure and having high rigidity to withstand external impacts. 
     Technical Solution 
     According to an aspect of the present invention, a method of manufacturing a solar cell panel using an autoclave includes (a) disposing at least one solar cell module on a mold having a release material layer, (b) stacking a prepreg on the mold to a certain thickness so as to cover the solar cell module, (c) covering a stacked structure of the solar cell module and the prepreg with a bagging film and sealing an inner space of the bagging film from the outside, and (d) making the inner space of the bagging film into a vacuum state, placing the mold into a chamber of an autoclave, and applying pressure and heat to compress and harden the prepreg, wherein, in (b), the mold is provided with a mounting space for forming a solar cell panel, and the prepreg is stacked in a state in which the solar cell module is inserted into a fixing groove formed in a mounting surface of the mounting space. 
     In an embodiment of the present invention, the mounting surface of the mold may have a certain curvature and may be upwardly convex. 
     In an embodiment of the present invention, the mounting surface of the mold may have a certain curvature and may be concave. 
     In an embodiment of the present invention, in operation (b), the fixing groove may be recessed to a depth sufficient to outwardly expose a portion of the solar cello module and the prepreg may be stacked to cover the exposed portion. 
     In an embodiment of the present invention, the prepreg may include a first region corresponding to the solar cell module, and a second region formed in a peripheral region of the first region along an inner side of the mounting space. 
     In an embodiment of the present invention, the prepreg may be stacked to be thicker in the second region than in the first region. 
     Advantageous Effects 
     According to an embodiment of the present invention, a highly rigid and lightweight solar cell panel can be manufactured using an autoclave technique after forming a curved structure by stacking a prepreg in multiple layers in a state in which a fixing groove is formed in a mounting space of a mold to increase the accuracy of arrangement of a solar cell module. 
     The solar cell panel manufactured by the above method can be installed on the top of a vehicle without an additional fixing structure and used as a component of the body of the vehicle, which has rigidity sufficient to withstand external impacts. 
    
    
     
       DESCRIPTION OF DRAWINGS 
         FIG. 1  is a flowchart of a manufacturing method of a solar cell panel according to a first embodiment of the present invention. 
         FIG. 2  is a cross-sectional view illustrating a process of the manufacturing method of a solar cell panel according to the first embodiment of the present invention. 
         FIG. 3  is a schematic diagram of a first mold for manufacturing a solar cell panel according to the first embodiment of the present invention. 
         FIG. 4  is a cross-sectional view illustrating a process of a manufacturing method of a solar cell panel according to a second embodiment of the present invention. 
         FIG. 5  is a schematic diagram of a second mold for manufacturing a solar cell panel according to the second embodiment of the present invention. 
         FIG. 6  is a schematic cross-sectional view illustrating a state in which a first solar cell panel according to the first embodiment and a second solar cell panel according to the second embodiment of the present invention are connected to each other on the top of a vehicle. 
     
    
    
     MODES OF THE INVENTION 
     Hereinafter, configurations and operations of embodiments of the present invention will be described in detail with reference to the accompanying drawings. 
     However, it should be understood that the present invention is not limited to particular embodiments and include all modifications, equivalents, and alternatives falling within the idea and scope of the present invention. 
     It should be understood that the terms “comprise” and/or “comprising”, when used herein, specify the presence of stated features, steps, operations, elements, components, or a combination thereof, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, or a combination thereof. That is, it will be understood that when an element is referred to as “including” another element, the element may further include other elements unless specifically mentioned otherwise. 
       FIG. 1  is a flowchart of a manufacturing method of a solar cell panel according to a first embodiment of the present invention.  FIG. 2  is a cross-sectional view illustrating a process of the manufacturing method of a solar cell panel according to the first embodiment of the present invention.  FIG. 3  is a schematic diagram of a first mold for manufacturing a solar cell panel according to the first embodiment of the present invention. 
     Referring to  FIG. 1 , a manufacturing method of a solar cell panel according to an embodiment of the present invention may include disposing a solar cell module (S 100 ), stacking a prepreg (S 200 ), performing sealing (S 300 ), and performing compressing and hardening (S 400 ). 
     Referring to  FIGS. 2 and 3 , a first mold  100  may be formed of a metal to form a solar cell panel including a prepreg having a certain level of curvature and a curved shape. Here, the metal may be aluminum or steel. 
     In the disposing of the solar cell module (S 100 ) according to an embodiment of the present invention, the solar cell module  10  may be disposed on the first mold  100  provided to manufacture a solar cell panel. 
     The solar cell module  10  according to an embodiment of the present invention may include a solar cell  11 , an encapsulation layer (EVA sheet)  12  covering an outer side of the solar cell  11  while exposing an electrode terminal (not shown) of the solar cell  11 , and a light transmission layer  13  provided on a side of the encapsulation layer  12 . 
     According to an embodiment of the present invention, the first mold  100  may include a first mounting space  110  for forming a solar cell panel having a curved surface. 
     The first mounting space  110  may be formed in a quadrilateral shape when viewed from a plane, and a first mounting surface  110   a  may have an upwardly convex shape having a certain curvature on an xy plane. 
     A first fixing groove  112  may be formed in the first mounting surface  110   a  to increase the accuracy of arrangement of the solar cell module  10 . 
     According to an embodiment of the present invention, the first fixing groove  112  may be recessed to a certain depth while forming a step with the first mounting surface  110   a  of the first mounting space  110 . 
     The first fixing groove  112  may be formed with a first fixing bottom surface  112   a  that is upwardly convex on the XY plane, and the first fixing bottom surface  112   a  may have a convex shape having the same curvature as the first mounting surface  110   a  of the first mounting space  110 . 
     Although in the drawings of the present specification, the first fixing bottom surface  112   a  and the first mounting surface  110   a  have the same curvature, the first fixing bottom surface  112   a  and the first mounting surface  110   a  may be formed to have different curvatures when a shape of a solar cell module used in the manufacture of the solar cell panel is changed. 
     According to an embodiment of the present invention, the solar cell module may be inserted into the first fixing groove  112 , and the first fixing groove  112  guides the solar cell module  10  to be accurately disposed on the first mold  100 . 
     According to an embodiment of the present invention, the depth to which the first fixing groove  112  is recessed may be less than a thickness of the solar cell module  10 . Due to the above structure, when the solar cell module  10  is inserted into the first fixing groove  112 , some of the outer surfaces of the solar cell module  10  may be brought into contact with the prepreg  20  to be integrally formed with the prepreg  20  in a manufactured solar cell panel. 
     According to an embodiment of the present invention, a release material layer  5  may be formed on an outer surface of the first mold  100  before the solar cell module  10  is disposed on the first mold  100 . The release material layer  5  may be formed on the entire outer surfaces of the first mounting space  110  of the first mold  100  and the first fixing groove  112 . 
     The release material layer  5  may be formed to prevent a resin contained in the prepreg  20 , which is to be compressed and stacked in subsequent operations, from being eluted and attached to the first mold  100 , and may be formed by attaching a release film or applying a release agent. 
     Therefore, in the disposing of the solar cell module (S 100 ), the solar cell module  10  may be inserted into the first fixing groove  112  of the first mold  100  in which the release material layer  5  is formed on the outer surface thereof, and fixedly positioned in the first fixing groove  112 . 
     Next, in the stacking of the prepreg (S 200 ) according to an embodiment of the present invention, the prepreg  20  may be stacked to cover exposed portions of the solar cell module  10 . 
     The prepreg  20  is formed of fibrous cloth in which a fiber is impregnated with a resin in advance, and a user may stack a prepreg in multiple layers on a desired position to a desired thickness. 
     Accordingly, the prepreg  20  may be stacked to the desired thickness to cover outer sides of the first mold  100  having the release material layer  5  and an exposed portion, e.g., portions of a top surface and an outer side, of the solar cell module  10 . 
     In an embodiment of the present invention, the prepreg  20  may be stacked such that a first region S 1  and a second region S 2  thereof have different thicknesses t 1  and t 2 . 
     The first region S 1  is a region spaced a certain distance from an inner side of the first mounting space  110  and corresponding to the solar cell module  10 , and the second region S 2  is a region having a certain width and formed along the inner side of the first mounting space  110 . 
     The prepreg  20  may have a first thickness t 1  in the first region S 1  and have a second thickness t 2  in the second region S 2 , and the second thickness t 2  may be greater than the first thickness t 1 . 
     Next, the performing of the sealing (S 300 ) and the performing of the compressing and hardening (S 400 ) may be performed to form a vacuum bag. 
     In the performing of the sealing (S 300 ) according to an embodiment of the present invention, a stacked structure including the solar cell module  10  and the prepreg  20  and having a curved shape may be covered with a bagging film  6 . The bagging film  6  may be attached to an outer side of the first mold  100  via a sealant  7  provided along an edge of the bagging film  6  to seal an inner space of the bagging film  6  from the outside. 
     In the performing of the compressing and hardening (S 400 ) according to an embodiment of the present invention, a connector  8  communicating with the inside of the bagging film  6  is provided and connected to a vacuum pump (not shown) through a vacuum hose  9  to apply vacuum pressure to the inside of the bagging film  6 , thereby causing the bagging film  6  to be in a vacuum state. 
     After causing the bagging film  6  to be in the vacuum state, the first mold  100  may be placed in a chamber of an autoclave and heat and pressure may be applied thereto to compress a first solar cell panel  150  including the prepreg  20 . A temperature and pressure in the chamber of the autoclave are adjustable if necessary for compressing the prepreg  20 . 
     After the performing of the compressing and hardening (S 400 ), when a first solar cell panel  150  including the prepreg  20  is taken out of the first mold  100 , the first solar cell panel  150  having a concave portion in which the light transmission layer  13  is provided and a concave portion in which the prepreg  20  is provided may be manufactured (see  FIG. 6 ). 
     A solar cell panel manufactured as described above may be provided as a highly rigid and lightweight component of a body of a vehicle and may generate solar light when applied to a loop of the body of the vehicle. 
       FIG. 4  is a cross-sectional view illustrating a process of a manufacturing method of a solar cell panel according to a second embodiment of the present invention.  FIG. 5  is a schematic diagram of a second mold for manufacturing a solar cell panel according to the second embodiment of the present invention. 
     The solar cell panel according to the second embodiment of the present invention may be manufactured using a second mold  200  different from the first mold  100  used to manufacture the solar cell panel according to the first embodiment. 
     Referring to  FIGS. 4 and 5 , the second mold  200  may include a second mounting space  210  for forming a solar cell panel having a curved surface, and the second mounting space  210  may be formed in a quadrilateral shape when viewed from a plane and include a second mounting surface  210   a  having a concave shape with a constant curvature on an xy plane. 
     A second fixing groove  212  into which a solar cell module  10  is insertable may be formed in the second mounting surface  210   a , and may be recessed to a certain depth while forming a step with the second mounting surface  210   a  of the second mounting space  210 . 
     The second fixing groove  212  may be formed with a second fixing bottom surface  212   a  that is concave on the xy plane, and the second fixing bottom surface  212   a  may have a concave shape having the same curvature as the second mounting surface  210   a  of the second mounting space  210  but the second fixing bottom surface  212   a  and the second mounting surface  210   a  may have different curvatures according to a degree to which the solar cell module  10  is curved. According to an embodiment of the present invention, the solar cell module  10  may be inserted into the second fixing groove  212 , and the second fixing groove  212  may increase the accuracy of arrangement of the solar cell module  10  with respect to the second mold  200 . 
     According to an embodiment of the present invention, the depth to which the second fixing groove  212  is recessed may be less than the thickness of the solar cell module  10 . 
     An order in which a solar cell panel according to the second embodiment of the present invention is manufactured using the second mold  200  is the same as the order in which the solar cell panel according to the first embodiment is manufactured and thus a description thereof will be omitted here. 
     A second solar cell panel  250  manufactured by the manufacturing method according to the second embodiment of the present invention may have a convex portion in which a light transmission layer  13  is provided and a concave portion in which a prepreg  20  is provided. 
       FIG. 6  is a schematic cross-sectional view illustrating a state in which a first solar cell panel according to the first embodiment and a second solar cell panel according to the second embodiment of the present invention are connected to each other on the top of a vehicle. 
     A first solar cell panel  150  in which a solar cell module  10  is formed in a concave shape may be disposed on a concave portion of the top of a vehicle and a second solar cell panel  250  in which a solar cell module  10  is formed in a convex shape may be disposed on an upwardly convex portion of the top of the vehicle. 
     In addition, a degree to which a solar cell panel, which is a curved stacked structure, is bent may be adjusted by forming a mounting space of a mold and a fixing groove in different forms. 
     Therefore, solar cell panels having different shapes may be combined together and disposed according to a shape of the top of a vehicle. 
     While the present invention has been described above with reference to the embodiments illustrated in the drawings, these embodiments are merely examples and it will be understood by those of ordinary skill in the art that various modifications and other equivalent embodiments may be made. Therefore, the technical scope of the present invention should be defined by the technical idea of the appended claims.