Battery assembly and photovoltaic system

Abstract

The utility model discloses a battery assembly and a photovoltaic system. The battery assembly comprises a battery string, a first insulating strip and a first bus bar; the battery string comprises at least two battery pieces, the at least two battery pieces are arranged along a first direction and are connected in series, and a first conductive region is arranged on the first piece; the first insulating strip is stacked on the first position sheet and covers the first conductive region, and the two ends of the first conductive region are exposed out of the first insulating strip; the first bus bar is stacked on the surface of one side, far away from the first position sheet, of the first insulating strip; wherein two adjacent battery pieces are connected through a first welding strip or a second welding strip, the first welding strip is connected to the first bus bar, the second welding strip is connected to the first end of the first conductive area, and the first end of the first conductive area is one end close to the last piece. The battery assembly provided by the utility model is high in conversion efficiency and safety.

Description

Technical Field

[0001] This application belongs to the field of photovoltaic cell technology, specifically relating to a battery module and a photovoltaic system. Background Technology

[0002] In existing back-contact battery modules, the series busbars between adjacent battery strings are typically placed at the edge of the module. This necessitates reserving space at the edge of the module to accommodate the series busbars, and similarly, space is required between two parallel battery strings to accommodate parallel busbars. This arrangement impacts module conversion efficiency. To improve conversion efficiency, existing technologies extend the solder ribbon below the busbars, but this method leads to stress concentration at the busbars, causing microcracks in the battery cells. Utility Model Content

[0003] This application aims to provide a battery module and photovoltaic system that addresses at least one of the problems in the prior art.

[0004] According to a first aspect of this application, a battery assembly is provided, comprising:

[0005] A battery string, comprising at least two battery cells, the at least two battery cells being arranged along a first direction and connected in series with each other, the battery cells located at both ends of the battery string being a first cell and a last cell, the first cell being provided with a first conductive area extending along the first direction;

[0006] A first insulating strip is stacked on the first and second plates and covers the first conductive area, with both ends of the first conductive area exposed above the first insulating strip. The first insulating strip extends along a second direction, which intersects with the first direction.

[0007] The first busbar is stacked on the side surface of the first insulating strip away from the first and second plates and extends along the second direction;

[0008] In this configuration, two adjacent battery cells are connected by a first solder strip or a second solder strip. The first solder strip is connected to the first busbar, and the second solder strip is connected to the first end of the first conductive area. The first end of the first conductive area is the end closest to the last cell.

[0009] Optionally, the second end of the first conductive region is the end away from the last piece, and the second end of the first conductive region extends to the edge of the first and second pieces.

[0010] Optionally, the projection of the first busbar on the first and second plates falls within the projection of the first insulating strip.

[0011] Optionally, the first insulating strip is located at the edge of the first and second pieces on the side away from the last piece.

[0012] Optionally, the solar cell is a gridless solar cell.

[0013] Optionally, the first conductive area is solder paste or conductive adhesive.

[0014] Optionally, the battery cells located between the first and last cells are all intermediate cells, and each intermediate cell is spliced ​​with the first and last cells along the first direction.

[0015] Optionally, the battery assembly includes at least two battery strings, which are arranged side by side along the second direction;

[0016] Two adjacent battery strings are connected in series via the first busbar, and both the first busbar and the first insulating strip extend from the first end piece of one battery string to the first end piece of the adjacent battery string.

[0017] Optionally, the battery assembly further includes a second insulating strip and a second busbar, and the last piece is provided with a second conductive area extending along the first direction;

[0018] The second insulating strip is stacked on the last piece and covers the second conductive area, with both ends of the second conductive area exposed on the second insulating strip. The second insulating strip extends along the second direction. The second busbar is stacked on the surface of the second insulating strip away from the last piece and extends along the second direction.

[0019] The second solder strip is connected to the second busbar, and the first solder strip is connected to the first end of the second conductive area, the first end of the second conductive area being the end closest to the first and second plates.

[0020] Optionally, the battery assembly includes two battery strings, which are arranged side by side along the first direction and connected in parallel via the second busbar;

[0021] The second busbar is disposed on the last piece of the first battery string, and the second solder strip on the first battery string and the first solder strip on the second battery string are both connected to the second busbar.

[0022] According to a second aspect of this application, a photovoltaic system is provided, comprising: the battery module described in the first aspect.

[0023] This application improves the module conversion efficiency by setting a first conductive area on the first and second sheets and extending the first conductive area to the position between the first insulating strip and the first and second sheets, so that the first solder strip and the second solder strip can collect the current at the position on the first and second sheets that is blocked by the first insulating strip.

[0024] Meanwhile, the setting of the first conductive area, compared to the method of directly extending the first solder strip to the space between the first insulating strip and the first and second plates, avoids the problem of stress concentration at the busbar and improves the safety of the battery module.

[0025] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0026] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0027] Figure 1 This is a schematic diagram of the battery assembly provided in this application;

[0028] Figure 2 yes Figure 1 A magnified view of a section at point A in the middle;

[0029] Figure 3 yes Figure 1 A magnified view of a section at point B in the middle;

[0030] Figure 4 This is a schematic diagram of the structure of multiple battery components connected as provided in this application;

[0031] Figure 5 yes Figure 4 A magnified view of a section at point C;

[0032] Figure 6 yes Figure 4 A magnified view of a section at point D.

[0033] Figure label:

[0034] 1. Battery string; 11. First strip; 111. First conductive area; 12. Last strip; 121. Second conductive area; 13. First solder strip; 14. Second solder strip; 15. Intermediate strip; 2. First insulating strip; 3. First busbar; 4. Second insulating strip; 5. Second busbar. Detailed Implementation

[0035] Embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application are within the scope of protection of this application.

[0036] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0037] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0038] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0039] like Figures 1 to 2As shown, according to a first aspect of this application, a battery assembly is provided, including: a battery string 1, a first insulating strip 2, and a first busbar 3; the battery string 1 includes at least two battery cells, which are arranged and connected in series along a first direction (Y direction in the figures), and the battery cells located at both ends of the battery string 1 are a first terminal cell 11 and a last terminal cell 12, respectively. The first terminal cell 11 is provided with a first conductive region 111 extending along the first direction; the first insulating strip 2 is stacked on the first terminal cell 11 and covers the first conductive region 111, and the first conductive region 111... 1. Both ends are exposed on the first insulating strip 2, which extends along the second direction (X direction in the figure) and intersects with the first direction; the first busbar 3 is stacked on the surface of the first insulating strip 2 away from the first and second sheets 11 and extends along the second direction; wherein, two adjacent battery sheets are connected by a first solder strip 13 or a second solder strip 14, the first solder strip 13 is connected to the first busbar 3, and the second solder strip 14 is connected to the first end of the first conductive area 111, the first end of the first conductive area 111 being the end near the last sheet 12.

[0040] Specifically, in this embodiment, the provided battery assembly is a back-contact battery assembly comprising a battery string 1 formed by multiple battery cells connected in series, a first insulating strip 2 disposed on the first end sheet 11 at the beginning of the battery string 1, and a busbar disposed on the first insulating strip 2. The first insulating strip 2 and the first busbar 3 are typically disposed on the back side of the first end sheet 11. The front side of the battery cell is the light-receiving surface. Each battery cell has a fine grid area on its back side for collecting current in the positive electrode region and current in the negative electrode region. A first solder ribbon 13 and a second solder ribbon 14 can be respectively disposed in the positive and negative electrode regions by lamination welding, thereby forming an electrical connection with the fine grid and guiding the current. The battery cells can be connected to each other to form the battery string 1 via the first solder ribbon 13 or the second solder ribbon 14. For example, one end of the first solder ribbon can be directly connected to the first busbar 3, and the other end can extend to the battery cell adjacent to the first end sheet 11, realizing the connection of two battery cells. The battery string 1 can be connected in series or in parallel to form a complete solar panel.

[0041] Furthermore, the first insulating strip 2 in this application can isolate the first conductive area 111 located on the back of the first and second sheets 11 and the first busbar 3 located on the surface of the first insulating strip 2 away from the first and second sheets 11, preventing short circuits between the first solder strip 13 connected to the first busbar 3 and the second solder strip 14 connected to the first conductive area 111, thus ensuring the safety of the battery module. The first conductive area 111 on the first and second sheets 11 in this application can be printed using conductive materials such as solder paste or conductive adhesive, and its thickness is relatively thin. On the one hand, this allows the current collected by the fine grid on the first and second sheets 11, which is shielded by the first insulating area, to be guided to the second solder strip 14 through the first conductive area 111, thereby improving the conversion efficiency of the battery module. On the other hand, it avoids stress concentration caused when the second solder strip 14 extends directly between the first insulating area and the first and second sheets 11, preventing microcracks in the battery cells and improving the yield of the battery module.

[0042] Understandably, reference Figure 2 Each cell has multiple first solder strips 13 and second solder strips 14 arranged at intervals along the second direction. The first conductive area 111 also has multiple strips arranged at intervals along the second direction. Each first solder strip 13 is connected to the first busbar 3 and is also connected to one of the corresponding first conductive areas 111 to collect the current at the corresponding position blocked by the first insulating strip 2. Each second solder strip 14 is also connected to one of the first conductive areas 111. The first solder strips 13 and the second solder strips 14 are insulated from each other, so as to collect the positive and negative current at the position blocked by the first insulating strip 2 and improve the conversion efficiency of the module.

[0043] In the above embodiment, the first insulating strip 2 can extend along the second direction and be disposed at any position of the first and second pieces 11. The first conductive area 111 is disposed along the first direction corresponding to the position of the first insulating strip 2. That is, the first conductive area 111 can extend from the side of the first insulating strip 2 near the last piece 12 to the side away from the last piece 12, exposing the first insulating area to facilitate connection with the second solder strip 14. When connecting between battery strings 1, it is convenient for the solder strips on other battery strings 1 to connect to the first conductive area 111 and form a full-screen assembly. The first direction and the second direction intersect, which usually means that the angle between the first direction and the second direction is about 90 degrees. The specific design can be made according to actual needs.

[0044] Optionally, such as Figures 1 to 2 As shown, the second end of the first conductive region 111 is the end away from the last piece 12, and the second end of the first conductive region 111 extends to the edge of the first and second pieces 11.

[0045] Specifically, in this embodiment, the end of the first conductive region 111 that is not connected to the second solder strip 14 extends directly to the outer edge of the first and second plates 11 to maximize the collection and guidance of the current collected by the fine grid, thereby further improving the conversion efficiency of the battery module.

[0046] Optionally, such as Figures 1 to 2 As shown, the projection of the first busbar 3 on the first and second plates 11 falls within the projection of the first insulating strip 2.

[0047] Specifically, in this embodiment, the first busbar 3 is stacked above the first insulating strip 2 to collect the current guided by the first solder strip 13. The size of the first insulating strip 2 completely covers the first busbar 3, which can completely isolate the first busbar 3 from contact with the first and second plates 11 or the second solder strip 14, thereby improving the safety of the battery assembly.

[0048] Optionally, such as Figure 1 As shown, the first insulating strip 2 is located at the edge of the first and second pieces 11 on the side away from the last piece 12.

[0049] Specifically, in this embodiment, the first insulating strip 2 is disposed at the edge of the first leading sheet 11 on the side away from the last leading sheet 12, so that the second solder strip 14 connected to the first conductive area 111 can extend continuously without being broken on the first leading sheet 11, thus improving assembly efficiency. In addition, disposing of the first insulating strip 2 in the edge region facilitates the entire battery string 1 to be connected in series or in parallel with other battery cells.

[0050] Optionally, the solar cell is a gridless solar cell. That is, the above-described structure of this application is more applicable to gridless solar cells. It can be understood that a gridless solar cell refers to a solar cell with fine grids but no main grids, and the current on the fine grids is directly discharged through the electrical connection between the first solder ribbon 13 or the second solder ribbon 14 and the fine grids.

[0051] Optionally, such as Figures 1 to 2 As shown, both the first insulating strip 2 and the first busbar 3 are elongated strips.

[0052] Specifically, in this embodiment, both the first insulating strip 2 and the first busbar 3 are elongated, which can both collect current and reduce the shading area of ​​the battery cells, thereby improving the conversion efficiency of the battery module.

[0053] Optionally, the first conductive region 111 is solder paste or conductive adhesive.

[0054] Specifically, in this embodiment, the first conductive area 111 is printed with solder paste or conductive adhesive, which achieves the purpose of collecting current in the fine grid area and reduces the thickness of the first busbar area, avoiding the problem of microcracks in the battery caused by stress concentration during the pressing of the battery assembly, thus improving the safety of the battery assembly.

[0055] Optionally, the battery assembly includes at least two battery strings 1, which are arranged side by side along a second direction; wherein, two adjacent battery strings 1 are connected in series by a first busbar 3, and the first busbar 3 and the first insulating strip 2 both extend from the first end piece 11 of one battery string 1 to the first end piece 11 of the adjacent other battery string 1.

[0056] Specifically, such as Figure 4 and Figure 6 As shown, the battery strings 1 arranged along the second direction are connected in series. In the series structure, the first battery string 1 (located in...) Figure 6 Battery string 1 on the upper middle side and adjacent battery string 1 (located in the middle and upper side) Figure 6 The first insulating strip 2 and the first busbar 3 are stacked on the first and second plates 11 of the battery string 1 on the lower middle side. The first insulating strip 2 and the first busbar 3 on the two battery strings 1 extend to the same line. The first conductive area 111 is provided on the first and second plates 11 of the two battery strings 1 at the position covered by the first insulating strip 2, so that the first solder strip 13 on the first battery string 1 and the second solder strip 14 on the adjacent battery string 1 can be connected to the first busbar 3 at the same time, realizing the series connection of the two battery strings 1.

[0057] Meanwhile, in this series structure, the connection between the two battery strings 1 is achieved by the same busbar stacked on the first and second pieces 11, so that the first piece 11 of the first battery string 1 and the first piece 11 of the adjacent battery string 1 can be spliced ​​together to achieve full-screen connection, avoiding gaps between them and affecting the conversion efficiency of the photovoltaic system.

[0058] Optionally, such as Figures 1 to 3 As shown, the battery assembly also includes a second insulating strip 4 and a second busbar 5. A second conductive region 121 extending in a first direction is provided on the last piece 12. The second insulating strip 4 is stacked on the last piece 12 and covers the second conductive region 121, with both ends of the second conductive region 121 exposed above the second insulating strip 4. The second insulating strip 4 extends in a second direction. The second busbar 5 is stacked on the side surface of the second insulating strip 4 away from the last piece 12 and extends in the second direction. A second solder strip 14 is connected to the second busbar 5, and a first solder strip 13 is connected to the first end of the second conductive region 121. The first end of the second conductive region 121 is the end close to the first piece 11.

[0059] Specifically, in this embodiment, the last piece 12 of the battery string 1 is stacked with a second insulating strip 4 and a second busbar 5 to collect the current guided by the second solder strip 14, while the first busbar 3 collects the current guided by the first solder strip 13. This allows the positive and negative currents of the battery string 1 to be guided to both ends of the battery string 1, facilitating series or parallel connection between the battery strings 1. The second insulating strip 4 and the first insulating strip 2 are configured in the same way. The second conductive area 121 extends from the side of the second insulating strip 4 on the last piece 12 near the first piece 11 to the side away from the first piece 11. This allows the second solder strip 14 to guide the current in the second conductive area 121 located below the second insulating strip 4 to the second busbar 5, and also allows the first solder strip 13 to guide the current in the second conductive area 121 below the second insulating strip 4. Furthermore, this avoids stress concentration at the second insulating strip 4 (second busbar 5), preventing microcracks in the battery cells and improving the safety of the battery assembly. The second conductive area 121 can also be printed using solder paste or conductive adhesive.

[0060] Optionally, the battery assembly includes two battery strings 1, which are arranged side by side along a first direction and connected in parallel by a second busbar 5; wherein the second busbar 5 is disposed on the last piece 12 of the first battery string 1, and the second solder strip 14 on the first battery string 1 and the first solder strip 13 on the second battery string 1 are both connected to the second busbar 5.

[0061] Specifically, in this embodiment, such as Figure 4 and Figure 5 As shown, the battery assembly includes two battery strings 1, which are arranged in a first direction and connected in parallel. In the parallel structure, the first battery string 1 (located in...) Figure 5 A second insulating strip 4 and a second busbar 5 are stacked on the last piece 12 of the battery string 1 on the left side. A second conductive area 121 is provided on the last piece 12 at the position covered by the second insulating strip 4, and extends to the last piece 12 near the second battery string 1 (located in the middle). Figure 5 At one edge of the battery string 1 on the right side, the second solder strip 14 on the first battery string 1 and the second solder strip 14 on the second battery string 1 can be connected to the second bus bar 5 at the same time, so as to realize the parallel connection of the two battery strings 1.

[0062] Meanwhile, in this parallel structure, the connection between the two battery strings 1 is achieved through the second busbar 5 stacked on the last piece 12 of the first battery string 1, so that the last piece 12 of the first battery string 1 and the first piece 11 of the second battery string 1 can be spliced ​​together to achieve full-screen connection, avoiding gaps between them and affecting the conversion efficiency of the photovoltaic system.

[0063] Optionally, such as Figure 1As shown, the battery cells located between the first cell 11 and the last cell are all intermediate cells 15. The intermediate cells 15 are spliced ​​together with each other and with the first cell 11 and the last cell 12 respectively along the first direction.

[0064] Specifically, in practical applications, the battery string 1 typically includes multiple battery cells, with multiple intermediate cells 15 spliced ​​between the first cell 11 and the last cell 12, so that the entire battery string 1 can be assembled into a complete panel structure. When applied to a photovoltaic system, it can form a full-screen module, further improving the conversion efficiency of the photovoltaic system.

[0065] According to the second aspect of this application, such as Figures 4 to 6 As shown, a photovoltaic system is provided, including: a battery module in the first aspect.

[0066] Specifically, the photovoltaic system composed of the battery modules provided in the first aspect not only has a high full-screen conversion efficiency but also avoids the problem of microcracks in the battery cells, thus improving the safety of the photovoltaic system. In practical applications, the photovoltaic system may include multiple battery modules. Multiple battery strings 1 can be connected in parallel in the first direction and connected in series in the second direction to form a full-screen structure of the photovoltaic system, thereby improving the conversion efficiency of the photovoltaic system.

[0067] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0068] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery assembly, characterized in that, include: A battery string, comprising at least two battery cells, the at least two battery cells being arranged along a first direction and connected in series with each other, the battery cells located at both ends of the battery string being a first cell and a last cell, the first cell being provided with a first conductive area extending along the first direction; A first insulating strip is stacked on the first and second plates and covers the first conductive area, with both ends of the first conductive area exposed above the first insulating strip. The first insulating strip extends along a second direction, which intersects with the first direction. The first busbar is stacked on the side surface of the first insulating strip away from the first and second plates and extends along the second direction; In this configuration, two adjacent battery cells are connected by a first solder strip or a second solder strip. The first solder strip is connected to the first busbar, and the second solder strip is connected to the first end of the first conductive area. The first end of the first conductive area is the end closest to the last cell.

2. The battery assembly according to claim 1, characterized in that, The second end of the first conductive region is the end away from the last piece, and the second end of the first conductive region extends to the edge of the first and second pieces.

3. The battery assembly according to claim 1, characterized in that, The projection of the first busbar on the first and second plates falls within the projection of the first insulating strip.

4. The battery assembly according to claim 1, characterized in that, The first insulating strip is located at the edge of the first and second pieces on the side away from the last piece.

5. The battery assembly according to claim 1, characterized in that, The solar cell is a gridless solar cell.

6. The battery assembly according to claim 1, characterized in that, The first conductive area is solder paste or conductive adhesive.

7. The battery assembly according to claim 1, characterized in that, The battery cells located between the first and last cells are all intermediate cells, and each intermediate cell is spliced ​​together with the first and last cells along the first direction.

8. The battery assembly according to claim 1, characterized in that, The battery assembly includes at least two battery strings, which are arranged side by side along the second direction; Two adjacent battery strings are connected in series via the first busbar, and both the first busbar and the first insulating strip extend from the first end piece of one battery string to the first end piece of the adjacent battery string.

9. The battery assembly according to claim 1, characterized in that, It also includes a second insulating strip and a second busbar, and the last piece is provided with a second conductive area extending along the first direction; The second insulating strip is stacked on the last piece and covers the second conductive area, with both ends of the second conductive area exposed on the second insulating strip. The second insulating strip extends along the second direction. The second busbar is stacked on the surface of the second insulating strip away from the last piece and extends along the second direction. The second solder strip is connected to the second busbar, and the first solder strip is connected to the first end of the second conductive area, the first end of the second conductive area being the end closest to the first and second plates.

10. The battery assembly according to claim 9, characterized in that, The battery assembly includes two battery strings, which are arranged side by side along the first direction and connected in parallel via the second busbar; The second busbar is disposed on the last piece of the first battery string, and the second solder strip on the first battery string and the first solder strip on the second battery string are both connected to the second busbar.

11. A photovoltaic system, characterized in that, include: The battery assembly according to any one of claims 1-10.

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