Middleware of back contact battery assembly, preparation method of middleware and back contact battery assembly

Abstract

The invention relates to a middleware of a back contact battery assembly, a preparation method of the middleware and the back contact battery assembly, and the middleware of the back contact battery assembly comprises a cover plate, a first packaging adhesive film and a battery array which are sequentially arranged along a first direction, wherein the battery pieces in the battery array at least correspond to one sub-module in the first packaging adhesive film, and the sub-modules corresponding to any two battery pieces are different. By adopting the method, the problem that the whole plate can only be scrapped when an abnormal battery piece occurs in the current plate welding process can be solved, so that the yield of the back contact battery assembly is improved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor battery technology, and in particular to an intermediate component of a back-contact battery assembly, a preparation method thereof, and a back-contact battery assembly. Background Art

[0002] Back contact (BC) cells have the structural characteristic of having an unobstructed front side because all electrodes and grid lines are arranged on the back side of the cell. This structural characteristic enables BC cells to exhibit the excellent characteristic of high photoelectric conversion rate; therefore, BC cells have broad application prospects. BC battery components need to be manufactured through steps such as string welding, lamination, and packaging. In order to avoid the problem that the battery string formed after the welding of the solder joints and the solder ribbons in the string welding process is prone to warping due to the stress of the solder ribbons, which in turn leads to the problem of hidden cracks and fragments in the subsequent lamination, the plate welding process has been promoted. The advantage of the plate welding process is that it can improve the reliability of BC battery components; it mainly avoids the risk of warping of the battery string and subsequent hidden cracks and fragments of the battery cells by avoiding welding multiple battery cells into a battery string. At the same time, because plate welding does not require string welding, it can effectively improve the generation efficiency of BC batteries.

[0003] However, in the plate welding process, all battery cells need to be fixed on the front adhesive film. When abnormal battery cell welding occurs during the welding process, the entire plate can only be scrapped because rework requires difficult operations such as cutting the front adhesive film and separating the battery cells. This leads to insufficient yield of back-contact batteries. Summary of the invention

[0004] Based on this, it is necessary to provide an intermediate component of a back-contact battery assembly and a preparation method thereof, and a back-contact battery assembly to address the above-mentioned technical problems, so as to solve the problem that the entire panel can only be scrapped when abnormal battery cells appear in the current panel welding process, thereby improving the yield of the back-contact battery assembly.

[0005] In a first aspect, an embodiment of the present application provides an intermediate component of a back contact battery assembly, comprising:

[0006] A cover plate, a first packaging film, and a battery array are sequentially arranged along a first direction; wherein,

[0007] The battery cells in the battery array correspond to at least one submodule in the first packaging film, and the submodules corresponding to any two battery cells are different.

[0008] In one of the embodiments, along the second direction, the distance between any two adjacent submodules is 0.2-0.5 mm; wherein the second direction is perpendicular to the first direction.

[0009] In one embodiment, the battery cells in the battery array are arranged at intervals;

[0010] Along the second direction, the distance between any two adjacent battery cells is greater than or equal to the distance between any two adjacent submodules.

[0011] In one embodiment, a first area of ​​the first surface of the submodule is greater than or equal to a second area of ​​the second surface of the battery cell; wherein the first surface is connected to the second surface.

[0012] In one embodiment, the first packaging film is a single layer or multiple layers of film, and the components of the film include ethylene-vinyl acetate copolymer EVA and / or polyolefin elastomer POE.

[0013] In one embodiment, the intermediate component further includes an interconnecting ribbon and a bus ribbon; wherein the battery cells are electrically connected via the interconnecting ribbon and the bus ribbon.

[0014] In a second aspect, an embodiment of the present application provides a method for preparing an intermediate member of a back contact battery assembly according to the first aspect and any possible implementation manner, comprising:

[0015] heating a target area of ​​a first packaging film laid on the cover plate so that the first packaging film is bonded to the cover plate; wherein, in the first packaging film, a cross-linking degree of the target area is greater than a cross-linking degree of a non-target area;

[0016] Placing the battery cell on the submodule of the first packaging film, and heating the submodule to make the battery cell and the submodule bonded; wherein the contact area between the battery cell and the submodule corresponds to the target area,

[0017] The battery cell corresponds to at least one submodule, and the submodules corresponding to any two battery cells are different.

[0018] In a third aspect, an embodiment of the present application provides a method for maintaining an intermediate component of a back contact battery assembly according to the first aspect and any possible implementation manner, the method comprising:

[0019] Determine the abnormal battery cell in the battery array, and peel off the cover plate in the intermediate member;

[0020] Removing the first submodule corresponding to the abnormal battery cell, and removing the abnormal battery cell;

[0021] Putting a replacement battery cell into the position of the abnormal battery cell and a replacement submodule into the position of the first submodule, and heating them;

[0022] The cover plate is placed on a side of the first packaging film opposite to the battery array and heated.

[0023] In a third aspect, an embodiment of the present application provides a back contact battery assembly, comprising:

[0024] The middle piece, the second packaging film and the back plate of the back contact battery assembly described in the first aspect and any possible implementation manner; wherein,

[0025] Along a first direction in which the cover plate, the first packaging film and the battery array are arranged in the middle member, the middle member, the second packaging film and the back plate are laminated in sequence.

[0026] In a third aspect, an embodiment of the present application provides a method for preparing the back contact battery assembly of the third aspect, comprising:

[0027] Along a first direction in which the cover plate, the first packaging film and the battery array are arranged in the middle piece, the middle piece, the second packaging film and the back plate are stacked in sequence to form a laminated piece;

[0028] The stacked parts are laminated to obtain the back contact battery assembly.

[0029] The above-mentioned middle piece of the back-contact battery assembly and its preparation method, and the back-contact battery assembly, in the middle piece of the back-contact battery assembly, a first packaging film is arranged to be composed of multiple sub-modules, and the battery cells in the battery array correspond to at least one sub-module, so that when abnormal battery cells appear in the middle piece, the abnormal battery cells can be directly replaced, thereby avoiding the problem of scrapping the entire panel and effectively improving the yield of the back-contact battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0031] Figure 1 A schematic diagram of the structure of an intermediate component of a back contact battery assembly according to an embodiment;

[0032] Figure 2 is a schematic cross-sectional view of an intermediate member of a back contact battery assembly in one embodiment;

[0033] Figure 3 A schematic cross-sectional view of an intermediate member of a back contact battery assembly in another embodiment;

[0034] Figure 4 is a schematic cross-sectional view of an intermediate member of a back contact battery assembly in one embodiment;

[0035] Figure 5 A schematic flow chart of a method for preparing an intermediate member of a back contact battery assembly in one embodiment;

[0036] Figure 6 A flow chart of a method for middleware maintenance of a back contact battery assembly in one embodiment;

[0037] Figure numbers: 100 - middle piece of back contact battery assembly; 110 - cover plate; 120 - first packaging film; 121 - submodule; 130 - battery array; 131 - battery cell; 401 - interconnection ribbon; 402 - bus ribbon. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0039] It should be noted that the diagram provided in the present embodiment only illustrates the basic concept of the present application in a schematic manner, so the diagram only shows the components related to the present application rather than drawing according to the number, shape and size of the components during actual implementation. The form, quantity and ratio of each component during actual implementation can be a random change, and its component layout form may also be more complicated. The structure, proportion, size, etc. illustrated by the accompanying diagram of this specification are only used to match the content disclosed in the specification, so that people familiar with this technology can understand and read, and are not used to limit the restrictive conditions that can be implemented in this application, so they have no technical substantive significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effect that can be produced by this application and the purpose that can be achieved, should still fall within the scope that the technical content disclosed in this application can cover. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are also only for the convenience of narration, rather than for limiting the scope that can be implemented in this application. The change or adjustment of its relative relationship, without substantial change of technical content, should also be regarded as the scope that can be implemented in this application.

[0040] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the text does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0041] As shown in this document, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural, unless the context clearly indicates an exception. Generally speaking, the terms "include" and "comprise" only indicate that the steps and elements that have been clearly identified are included, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0042] The definitions of inclusion in this document, such as the terms "having", "may have", "including" or "may include" used herein, indicate the existence of the corresponding functions, operations, elements, etc. herein, and do not limit the existence of one or more other functions, operations, elements, etc. In addition, it should be understood that the terms "including" or "having" used herein indicate the existence of the features, numbers, steps, operations, elements, components, or a combination thereof described in the specification, and do not exclude the existence or addition of one or more other features, numbers, steps, operations, elements, components, or a combination thereof.

[0043] In the embodiment of the present application, prefixes such as "first" and "second" are used only to distinguish different description objects, and there is no limiting effect on the position, order, priority, quantity or content of the described object. The use of prefixes such as ordinal numbers to distinguish the description objects in the embodiment of the present application does not limit the described objects. The statement of the described objects refers to the description of the context in the claims or embodiments, and it should not constitute an unnecessary restriction due to the use of such prefixes. In addition, the term "including" and any of their variations are intended to cover non-exclusive protection. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. "Multiple" in the present application can mean at least two, for example, two, three or more, and the embodiment of the present application is not limited.

[0044] To facilitate understanding of the technical solution provided by the embodiments of the present application, the following first introduces the design concept of the embodiments of the present application:

[0045] At present, the plate welding process is divided into the following four steps. The first step is to place a front adhesive film on the front plate, and heat the front plate and the front adhesive film to thermally compound the two to form an assembly. The battery cell is placed in the battery area of ​​the assembly, and the battery cell is heated by a heating element so that the front adhesive film is bonded to the battery cell at high temperature to obtain an intermediate component. The second step is to place a soldering tape on the above-mentioned intermediate component containing the battery cell, and weld the soldering tape and solder joints by laser, infrared, etc. The third step is to place the back adhesive film and the back plate on the soldering tape in sequence to form a laminated structure to be laminated. The fourth step is to laminate the laminated structure to form a back contact battery assembly. It can be seen that the plate welding process realizes welding in the second step through the front adhesive film in the first step, thereby avoiding string welding: the battery cells are welded into battery strings, thereby avoiding the risk of warping of the battery string during welding, and hidden cracking or even fragmentation of the battery cells during lamination.

[0046] However, due to the pre-fixation of the battery cell and the cover plate by the pre-adhesive film in the first step of the plate welding, when the battery cell welding is abnormal, it is difficult to peel off the abnormal battery cell pre-adhesive film and the entire plate (i.e. the cover plate together with all the pre-fixed battery cells) can only be scrapped. This leads to a high material loss rate and insufficient yield of back contact battery modules.

[0047] To this end, the embodiment of the present application provides an intermediate component of a back-contact battery assembly, so that the first encapsulation film between the cover plate and the battery array is composed of submodules, each battery cell corresponds to at least one submodule, and each battery cell corresponds to a different submodule. In this way, it is convenient to repair the intermediate component when the battery cell welding is abnormal, and the abnormal battery cell can be directly replaced by peeling off the submodule corresponding to the abnormal battery cell, avoiding the current problem of material waste caused by scrapping the entire panel and insufficient yield of the back-contact battery assembly.

[0048] It should be noted that the first packaging film in the embodiment of the present application may also be referred to as a front packaging film, an upper packaging film, etc.

[0049] First, the present application embodiment provides an intermediate component of a back contact battery assembly, please refer to Figure 1 The middle piece 100 includes a cover plate 110 , a first packaging film 120 , and a battery array 130 which are sequentially arranged along a first direction y-axis.

[0050] The first packaging film 120 includes a plurality of submodules 121 , and the battery array 130 includes a plurality of battery cells 131 .

[0051] The battery cells 131 in the battery array 130 correspond to at least one submodule 121 in the first packaging film 120 , and any two battery cells 131 correspond to different submodules 121 , that is, any two battery cells 131 do not correspond to the same submodule 121 at the same time.

[0052] The number of the battery cells 131 in the battery array 130 is less than or equal to the number of the submodules in the first packaging film 120 .

[0053] The shapes of the submodules 121 in the first packaging film 120 may be the same or different.

[0054] For example, Figure 2 FIG. 1 is a cross-sectional schematic diagram of a middleware 100 according to an embodiment. Figure 2 As shown, the battery cells 131 in the battery array 130 may correspond one to one with the submodules 121 in the first packaging film 120 .

[0055] The number of the battery cells 131 in the battery array 130 is the same as the number of the submodules 121 in the first packaging film 120 .

[0056] For example, Figure 3 FIG. 1 is a cross-sectional schematic diagram of a middleware 100 according to an embodiment. Figure 3 As shown, in the battery array 130 , each battery cell 131 corresponds to two submodules 121 in the first packaging films 120 .

[0057] The number of the battery cells 131 in the battery array 130 is half the number of the submodules 121 in the first packaging film 120 .

[0058] For another example, in the battery array 130 , some battery cells 131 correspond to one submodule 121 , and some battery cells 131 correspond to two submodules 121 .

[0059] The number of the battery cells 131 in the battery array 130 is less than the number of the submodules 121 in the first packaging film 120 , and is greater than half of the number of the submodules 121 in the first packaging film 120 .

[0060] The cover plate 110 may be photovoltaic glass, which may be, for example, tempered glass or semi-tempered glass.

[0061] Furthermore, in the first packaging film 120 , any two adjacent submodules 121 may be connected or not connected.

[0062] When any two adjacent submodules 121 are not connected, the distance between any two adjacent submodules 121 along the second direction is less than 0.5 mm, preferably 0.2-0.5 mm. The second direction is perpendicular to the first direction and coplanar with the extension direction of the first packaging film 120.

[0063] The distance between the two adjacent submodules 121 is the distance between two opposite side surfaces of the two adjacent submodules 121 .

[0064] The opposite sides of the two submodules 121 may be parallel or non-parallel.

[0065] For example, among two adjacent submodules 121, one is a tetrahedron and the other is a cuboid, or both are tetrahedrons, and the two opposite sides are not parallel. In this case, the distance between the two submodules 121 is the shortest distance between any two points on the two opposite sides.

[0066] Furthermore, the battery cells 131 in the battery array 130 are arranged at intervals. Along the second direction, the distance between any two adjacent battery cells 131 is greater than or equal to the distance between any two adjacent submodules 121 .

[0067] The distance between two adjacent battery cells 131 is the distance between two opposite side surfaces of the two adjacent battery cells 131 .

[0068] To further prevent the first packaging film 120 from shrinking (i.e. shrinking) after being heated, the first surface of the submodule 121 has a first area greater than or equal to the second surface of the corresponding battery cell 131. The first surface is connected to the second surface. The submodule 121 is the submodule 121 corresponding to the battery cell 131.

[0069] When the battery cell 131 corresponds to a plurality of submodules 121 , the sum of the first surface areas of the plurality of submodules 121 is greater than or equal to the second area of ​​the second surface of the battery cell 121 corresponding to the plurality of submodules 121 .

[0070] Furthermore, the first packaging film 120 may be a single-layer film, or a multi-layer film stacked along the first direction.

[0071] Wherein, the components of any layer of adhesive film include ethylene-vinyl acetate copolymer EVA and / or polyolefin elastomer POE.

[0072] Optionally, any layer of the first packaging film 120 may be composed of one component or multiple components.

[0073] When the first packaging film 120 is a multi-layer film, the EVA film and the POE film in the multi-layer film may be overlapped.

[0074] For example, if the first packaging film 120 is a three-layer film, the three-layer film can be arranged in the order of EVA film, POE film, EVA film; or POE film, EVA film, POE film along the first direction.

[0075] For further information, please refer to Figure 4The intermediate component 100 further includes an interconnection ribbon 401 and a bus ribbon 402 . The battery cells 131 are electrically connected via the interconnection ribbon 401 and the bus ribbon 402 .

[0076] The interconnection ribbon 401 is correspondingly arranged between the intervals of the battery cells 131 of the battery array 130. The interconnection ribbon 401 is located on one side of the battery cell relative to the first packaging film 120. That is, the cover plate 110 and the first packaging film 120 are regarded as being located on the front side (i.e., the light-facing side) of the battery array 130, and the interconnection ribbon 401 is located on the back side (i.e., the backlight side) of the battery array 130.

[0077] The interconnection ribbon 401 is used to connect the individual battery cells 131 in series to form a battery string, which connects the positive and negative electrodes of adjacent battery cells 131 to form a continuous path for current.

[0078] The busbar 402 is used to connect the head section and the tail end of the battery string. The busbar 402 connects multiple battery strings to form a battery array 130.

[0079] The function of the bus ribbon 402 is to collect the current from the interconnect ribbon 401 and direct it to the edge of the solar panel or a specific output point (eg, a junction box).

[0080] The bus ribbon 402 is wider than the interconnect ribbon 401. Optionally, the bus ribbon 402 and the interconnect ribbon 401 may be tinned copper ribbons.

[0081] Based on the same inventive concept, the present application also provides a method for preparing the intermediate member 100 of the aforementioned back contact assembly. Figure 5 , the method comprises at least the following steps:

[0082] Step 501 : heating a target area of ​​the first packaging film 120 laid on the cover plate 110 to make the first packaging film 120 bonded to the cover plate 110 .

[0083] Specifically, the heating may be performed at a temperature of 60-150° C., and the heating time may be less than or equal to 100 seconds.

[0084] Furthermore, the area corresponding to the target area may be heated from one side of the cover plate 110 , so that the temperature is transferred to the target area of ​​the first packaging film 120 through the cover plate 110 .

[0085] Alternatively, the first packaging film may be heated directly from one side so that the target area is directly heated.

[0086] In the first packaging film 120 , the cross-linking degree of the target area is greater than that of the non-target area, that is, the adhesive force of the target area is greater than that of the non-target area.

[0087] Specifically, each submodule 121 in the first packaging film 120 contains a target area; the non-target area is the area of ​​each submodule 121 except the respective target area.

[0088] The target area may be heated so that the crosslinking degree of the target area is greater than that of the non-target area. The target area is the area on the first packaging film 120 that is bonded to the corresponding battery cell 131 .

[0089] The lower cross-linking degree in the non-target area of ​​the first packaging film 120 can avoid the risk of the first packaging film 120 being too hard as a whole due to excessive cross-linking, which may lead to cracking during the subsequent lamination of the back contact assembly.

[0090] Furthermore, the higher cross-linking degree in the target area of ​​the first packaging film 120 can avoid the risk of the first packaging film 120 being heated and shifted during welding during the preparation of the intermediate component 100 due to the low overall cross-linking degree and high film fluidity.

[0091] The above heating can be achieved, for example, by hot air, infrared and microwave heating. Taking hot air as an example, heating can be performed at a temperature of 60-150° C., and the heating time is less than or equal to 50 seconds.

[0092] Continuing with infrared heating as an example, heating can be performed at a temperature of 60-150° C., and the heating time is less than or equal to 100 seconds.

[0093] Step 502 , placing the battery cell 131 on the submodule 121 of the first packaging film 120 , and heating the submodule 121 to bond the battery cell 131 to the submodule 121 .

[0094] The battery cell 131 corresponds to at least one submodule 121 , and the submodules 121 corresponding to any two battery cells 131 are different, and the connecting area between the battery cell 131 and the submodule 121 corresponds to the target area.

[0095] The cover plate 110 and the battery cell 131 are respectively located on two sides of the first packaging film 120 .

[0096] Specifically, the heating may be performed at a temperature of 60-150° C., and the heating time may be less than or equal to 100 seconds.

[0097] For example, the connecting area may be a target area; or, the connecting area includes the target area; or, the target area includes the connecting area.

[0098] The heating method in this step can also be achieved by hot air, infrared and microwave heating. Taking hot air as an example, heating can be performed at a temperature of 60-150° C. and the heating time is less than or equal to 50 seconds.

[0099] As mentioned above, if infrared heating is used, heating can be performed at a temperature of 60-150° C., and the heating time is less than or equal to 100 seconds.

[0100] Furthermore, after step 502 , the interconnection ribbon 401 and the bus ribbon 402 may be welded at a preset position of the battery cell 131 to obtain the intermediate component 100 of the back contact battery.

[0101] Specifically, the interconnecting ribbon 401 is welded to the other side of the battery cell 131 relative to the first packaging film 120 to form a Figure 4 The cross-sectional structure shown: the interconnection ribbon 401 is correspondingly disposed between the intervals of the battery cells 131 of the battery array 130 .

[0102] The interconnection ribbon 401 is used to connect the individual battery cells 131 in series, and connects the positive and negative electrodes of adjacent battery cells 131 to form a continuous path for current, thereby obtaining a battery string.

[0103] The function of the busbar 402 is to collect the current from the interconnection ribbon 401. Please continue to refer to Figure 4 The busbar 402 connects the head end and the tail end of the battery string.

[0104] Therefore, after welding the interconnecting ribbon 401, the bus ribbon 402 may be welded to connect the head and tail ends of the battery string to form a battery array 130. The current from the interconnecting ribbon 401 is directed to the edge of the battery panel or a specific output point.

[0105] The welding method can be at least one of infrared welding, laser welding and lamination welding.

[0106] Based on the same inventive concept, the embodiment of the present application also provides a maintenance method for the middleware 100, which is used to efficiently repair the battery cell when abnormality occurs after welding and reduce the material loss rate. The battery cells 131 of the battery array 130 in the middleware 100 are electrically connected through the interconnection ribbon 401 and the bus ribbon 402. Please refer to Figure 6 , the maintenance method of the middleware 100 comprises the following steps:

[0107] Step 601 , determining abnormal battery cells in the battery array 130 , and peeling off the cover plate 110 in the middle piece 100 , that is, separating the cover plate 110 from the first packaging film 120 in the middle piece 100 .

[0108] Specifically, the abnormal cell can be determined by performing an EL (Electroluminescence) test on the middleware 100. Specifically, a forward bias voltage can be applied to both ends of the middleware 100 to determine the abnormal cell such as a cell with a hidden crack or a black core cell corresponding to the submodule 121 in the middleware 100.

[0109] Step 602, remove the first submodule corresponding to the abnormal battery cell, and remove the abnormal battery cell.

[0110] Specifically, the first submodule is a submodule in the first packaging film 120 corresponding to the abnormal battery cell. After removing the first submodule, the abnormal battery cell can be taken out through the gap in the first packaging film 120 after removing the first submodule.

[0111] Step 603: Place a replacement battery cell in the position of the abnormal battery cell and place a replacement submodule in the position of the first submodule, and heat them.

[0112] Specifically, the structure of the replacement battery cell is the same as that of the battery cell in the battery array 130. The shape of the replacement submodule is the same as that of the first submodule.

[0113] The replacement cell is used to replace the abnormal cell in the cell array 130 , and the replacement submodule is used to replace the first submodule in the first packaging film 120 , so that the first submodule is bonded to the replacement cell by heating.

[0114] The above heating may heat the replacement submodule directly, or heat only the target area on the replacement submodule corresponding to the replacement battery cell.

[0115] The heating method can still be implemented by the aforementioned hot air, infrared and microwave heating, and the temperature condition can be 60-150°C.

[0116] Step 604 , placing the cover plate 110 on the side of the first packaging film 120 opposite to the battery array 130 , and heating it.

[0117] Then it can be formed in sequence as follows Figure 1 The structure of the intermediate component 100 includes a cover plate 110 , a first packaging film 120 , and a battery array 130 .

[0118] The heating in step 604 can pass through all submodules including the replacement submodule in the first packaging film 120 to bond the cover plate 110 to the battery array 130 .

[0119] The above heating may heat the replacement submodule directly, or heat only the target area on the replacement submodule corresponding to the replacement battery cell.

[0120] The heating method can still be achieved by the aforementioned hot air, infrared and microwave heating.

[0121] In this way, through the maintenance method in the above steps 601-604, when abnormal battery cells appear again after welding the busbar 402 and the interconnection ribbon 401, they can be efficiently repaired by replacing the battery cells and sub-modules, and the problem of high material loss rate and insufficient yield of back contact battery components caused by scrapping the entire panel can be avoided.

[0122] It should be understood that although Figure 5-6 The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 5-6 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.

[0123] Based on the same inventive concept, the embodiment of the present application also provides a back contact battery assembly, which includes:

[0124] The aforementioned intermediate component 100, the second packaging film and the backplane.

[0125] Among them, along the first direction of the cover plate 110 , the first packaging film 120 and the battery array 130 in the middle piece 100 , the middle piece 100 , the second packaging film and the back plate are laminated in sequence.

[0126] Furthermore, the back-contact battery assembly may also include a junction box disposed on the back plate, and the junction box is used to form an electrical connection with the battery array 130.

[0127] Furthermore, the back-contact cell assembly may also include a photovoltaic frame, which is located at the edge of the back-contact cell assembly and covers the above-mentioned middle piece 100, the second packaging film and the back plate to play the role of mechanical protection, waterproof sealing, fixation, etc.

[0128] Furthermore, the back sheet may be a photovoltaic back sheet and / or photovoltaic glass.

[0129] Furthermore, the second packaging film can be a single-layer or multi-layer film independently of the first packaging film 120 .

[0130] When the second packaging film is a multi-layer film, it is still stacked along the first direction.

[0131] Wherein, the components of any layer of adhesive film include ethylene-vinyl acetate copolymer EVA and / or polyolefin elastomer POE.

[0132] Optionally, any layer of the second packaging film may be composed of one component or multiple components.

[0133] When the second packaging film is a multi-layer film, the EVA film and the POE film in the multi-layer film may be overlapped.

[0134] Based on the same inventive concept, the present application provides a method for preparing a back-contact battery assembly. The method for preparing a back-contact battery assembly is described below:

[0135] First, along a first direction in which the cover plate 110 , the first packaging film 120 and the battery array 130 in the middle piece 100 are arranged, the middle piece 100 , the second packaging film and the back plate are stacked in sequence to form a laminated piece.

[0136] Then, the stacked pieces are laminated to obtain a back contact battery assembly at a lamination temperature of 140-180° C. and a lamination pressure of 0.5-1.5 MPa.

[0137] After laminating the above-mentioned stacked components, the stacked components can be further framed using a photovoltaic frame to obtain a back-contact cell assembly.

[0138] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0139] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. An intermediate component (100) for a back contact battery assembly, characterized in that: include: A cover plate (110), a first packaging film (120), and a battery array (130) are sequentially arranged along a first direction; wherein: The battery cells (131) in the battery array (130) correspond to at least one submodule (121) in the first packaging film (120), and the submodules (121) corresponding to any two battery cells (131) are different.

2. The middleware (100) according to claim 1, characterized in that: Along the second direction, the distance between any two adjacent submodules (121) is 0.2-0.5 mm; wherein the second direction is perpendicular to the first direction.

3. The middleware (100) according to claim 1 or 2, characterized in that: The battery cells (131) in the battery array (130) are arranged at intervals; Along the second direction, the distance between any two adjacent battery cells (131) is greater than or equal to the distance between any two adjacent submodules (121).

4. The middleware (100) according to claim 1, characterized in that: A first area of ​​a first surface of the submodule (121) is greater than or equal to a second area of ​​a second surface of the battery cell (131); wherein the first surface is connected to the second surface.

5. The middleware (100) according to claim 1, characterized in that: The first packaging adhesive film (120) is a single layer or multiple layers of adhesive film, and the components of the adhesive film include ethylene-vinyl acetate copolymer EVA and / or polyolefin elastomer POE.

6. The middleware (100) according to any one of claims 1-2, 4-5, characterized in that: The intermediate component (100) further comprises an interconnection ribbon (401) and a bus ribbon (402); wherein the battery cell (131) is electrically connected via the interconnection ribbon (401) and the bus ribbon (402).

7. A method for preparing an intermediate member (100) of a back contact battery assembly according to any one of claims 1 to 6, characterized in that: include: heating a target area of ​​a first packaging adhesive film (120) laid on a cover plate (110) so that the first packaging adhesive film (120) is bonded to the cover plate (110); wherein, in the first packaging adhesive film (120), the cross-linking degree of the target area is greater than the cross-linking degree of the non-target area; A battery cell (131) is placed on the submodule (121) of the first packaging film (120), and the submodule (121) is heated to allow the battery cell (131) to bond to the submodule (121); wherein the contact area between the battery cell (131) and the submodule (121) corresponds to the target area, the battery cell (131) corresponds to at least one submodule (121), and the submodules (121) corresponding to any two battery cells (131) are different.

8. A method for maintaining the intermediate member (100) of the back contact battery assembly according to any one of claims 1 to 6, characterized in that: The method comprises: Determining abnormal battery cells in the battery array (130), and peeling off the cover plate (110) in the intermediate member (100); Removing the first submodule corresponding to the abnormal battery cell, and removing the abnormal battery cell; Putting a replacement battery cell into the position of the abnormal battery cell and a replacement submodule into the position of the first submodule, and heating them; The cover plate (110) is placed on a side of the first packaging adhesive film (120) opposite to the battery array (130), and heated.

9. A back contact battery assembly, characterized in that: include: The middle piece (100), the second packaging film and the back plate of the back contact battery assembly according to any one of claims 1 to 6; wherein: Along a first direction in which the cover plate (110), the first packaging film (120) and the battery array (130) are arranged in the middle piece (100), the middle piece (100), the second packaging film and the back plate are laminated in sequence.

10. A method for preparing the back contact battery assembly according to claim 9, characterized in that: include: Along a first direction in which the cover plate (110), the first packaging film (120) and the battery array (130) are arranged in the middle piece (100), the middle piece (100), the second packaging film and the back plate are stacked in sequence to form a stacked piece; The stacked parts are laminated to obtain the back contact battery assembly.

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