A battery module and photovoltaic system

Abstract

This application provides a battery module and a photovoltaic system. The battery module includes: a battery cell with multiple grid structures on its surface; and multiple connectors disposed on the side of the grid structures facing away from the battery cell, each connector being electrically connected to at least one grid structure. Each connector includes a conductive layer and a connecting layer, the connecting layer covering the outer surface of the conductive layer, and each connector's connecting layer forming an alloy interface with at least one grid structure. The maximum or average dimension of the connector in a first direction is a first dimension, and the maximum or average dimension of the connector in a third direction is a second dimension, with the ratio of the first dimension to the second dimension being 5.5 to 22.5. By setting the ratio of the connector's dimension in the first direction to its dimension in the third direction to be 5.5 to 22.5, the contact area between the connector and the battery cell can be increased, thereby improving the connection stability of the connector and ultimately enhancing the structural stability and efficiency of the battery module.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic technology, and in particular to a battery module and a photovoltaic system. Background Technology

[0002] With increasingly strained global energy supplies, developing new energy sources has become a crucial energy strategy for many countries. Solar energy, due to its relative availability, has attracted growing attention, and the solar cell industry has developed rapidly in recent years, with cell modules finding increasingly wider applications.

[0003] However, in existing battery modules, the battery cells are connected to connectors, but poor soldering is prone to occur between the battery cells and the connectors, resulting in insufficient connection stability of the connectors. Utility Model Content

[0004] This invention provides a battery module and a photovoltaic system to solve the technical problem of insufficient connection stability of connectors in battery modules.

[0005] This utility model provides a battery module and a photovoltaic system. The battery module includes battery cells with multiple grid structures on their surface; multiple connectors are disposed on the side of the grid structures facing away from the battery cells, each connector being electrically connected to at least one grid structure; the multiple connectors are spaced apart along a first direction, and extend along a second direction intersecting the first direction; wherein each connector includes a conductive layer and a connecting layer, the connecting layer wrapping around the outer surface of the conductive layer, and the connecting layer of each connector forming an alloy interface with at least one grid structure; the maximum or average size of the connector in the first direction is a first size, and the maximum or average size of the connector in a third direction is a second size, the ratio of the first size to the second size being 5.5 to 22.5, and the third direction being the same as the thickness direction of the battery module. In the battery assembly of this utility model embodiment, the ratio of the maximum or average size of the connector in the first direction to the maximum or average size of the connector in the third direction is 5.5 to 22.5, which can increase the contact area between the connector and the battery cell, thereby improving the connection stability of the connector, and thus improving the structural stability and efficiency of the battery assembly.

[0006] Furthermore, the conductive layer includes a first conductive portion and a second conductive portion, with the second conductive portion wrapping around the outer surface of the first conductive portion. The connecting layer also wraps around the outer surface of the second conductive portion, and the materials of the first and second conductive portions are different. This allows the first and second conductive portions in the conductive layer to be made of different materials, increasing the flexibility in the manufacturing of the conductive layer. In different application scenarios, the material combinations and structural parameters of each part of the conductive layer can be flexibly adjusted to achieve targeted optimization.

[0007] Furthermore, the second conductive part is one of copper, silver, or gold. Thus, by using copper, silver, or gold, which have good conductivity, the conductivity of the connector can be increased, resulting in a good conductive connection between the connector and the battery cell.

[0008] Furthermore, the first conductive part is either an aluminum conductive part or a nickel conductive part. Thus, by using aluminum or nickel as the first conductive part, which have lower costs, the manufacturing cost of the connector can be reduced.

[0009] Furthermore, the conductivity of the second conductive part is greater than that of the first conductive part. This ensures that the outer layer of the connector has good conductivity, guaranteeing the connection quality and conductivity at the contact point between the connector and the battery cell, without affecting the overall electrical performance.

[0010] Furthermore, the connecting layer is one of a tin-silver alloy connecting layer, a tin-copper alloy connecting layer, a tin-zinc alloy connecting layer, a tin-bismuth alloy connecting layer, a tin-indium alloy connecting layer, a tin-lead alloy connecting layer, a tin-lead-silver alloy connecting layer, or a tin-lead-bismuth alloy connecting layer. In this way, the connecting layer can form a low-resistance intermetallic compound with the grid structure, which can significantly reduce current transmission losses in the battery module, while also possessing excellent resistance to thermal fatigue and corrosion, enabling long-term stable operation in harsh environments (such as high temperature and salt spray), thereby increasing the stability of the battery module.

[0011] Furthermore, the solar cell is a solar cell with a main grid, and the plurality of grid line structures include main grids and fine grids. The connecting layer of each connector forms an alloy interface with one of the main grids of the solar cell. This allows each main grid of the solar cell to form a stable conductive connection structure with the connector, thereby ensuring the stability and reliability of the current transmitted through the main grid. In addition, forming an alloy interface between the connecting layer and the main grid not only helps to reduce contact resistance but also enhances welding strength and interface stability, improving the long-term reliability of the solar module under thermal cycling and environmental aging conditions.

[0012] Furthermore, the solar cell is a gridless solar cell, and the plurality of grid structures include a plurality of fine grids. The connecting layer of each connector forms an alloy interface with the plurality of fine grids of the solar cell. In this way, multiple fine grids can simultaneously form a stable and uniform conductive connection with the connector, which helps to disperse the current transmission path, reduce local current density, thereby reducing resistance loss and heat generation, and improving the overall conductivity and thermal stability of the solar cell assembly.

[0013] Furthermore, the solar cell is a gridless solar cell, and the multiple grid structures include multiple fine grids. The connecting layer of each connector forms an alloy interface with one of the fine grids of the solar cell. This helps to achieve a one-to-one conductive connection between the fine grids and the connectors, ensuring a clear and stable current transmission path, reducing the contact resistance between the fine grids and the connectors, and improving the mechanical strength and conductive reliability of the welded interface. Furthermore, the multiple fine grids are evenly distributed on the surface of the solar cell, and each connector is connected to a different fine grid, which effectively disperses the current-carrying pressure, improves the overall current carrying capacity and resistance to local failures of the solar module, thereby enhancing the operational stability and long-term reliability of the solar module.

[0014] Furthermore, the connector is a solder strip, and the solder strip is a flat solder strip. By setting the solder strip as a flat solder strip, under the same conductivity, the amount of encapsulant used in the module encapsulation process can be reduced by optimizing the thickness, thereby reducing the module encapsulation cost.

[0015] Furthermore, the cross-sectional shape of the solder strip is at least one of a trapezoidal or rectangular shape. Setting the cross-sectional shape of the solder strip to at least one of a trapezoidal or rectangular shape can increase the contact area between the solder strip and the battery cell, thereby improving the connection stability and ultimately improving the structural stability and efficiency of the battery module.

[0016] This utility model embodiment also provides a photovoltaic system, which includes the battery module as described above. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of a photovoltaic system module provided in one embodiment of the present invention;

[0019] Figure 2This is a schematic diagram of the grid line arrangement when the battery cell in the battery assembly provided in one embodiment of the present invention is a battery cell without a main grid line;

[0020] Figure 3 yes Figure 2 The diagram shown illustrates the structure of a battery cell with connectors.

[0021] Figure 4 This is a schematic diagram of the grid line arrangement when the battery cell in the battery assembly provided in another embodiment of the present invention is a battery cell without a main grid line;

[0022] Figure 5 yes Figure 4 The diagram shown illustrates the structure of a battery cell with connectors.

[0023] Figure 6 This is a schematic diagram of the grid line arrangement when the battery cell in the battery assembly provided in another embodiment of the present invention is a battery cell with a main grid line;

[0024] Figure 7 yes Figure 6 The diagram shown illustrates the structure of a battery cell with connectors.

[0025] Figure 8 This is a schematic diagram of the structure of the connector when it is not connected to the battery cell, according to another embodiment of the present invention;

[0026] Figure 9 This is a schematic diagram of the cross-sectional structure of a battery assembly provided in one embodiment of the present invention;

[0027] Figure 10 This is a schematic diagram of the cross-sectional structure of a battery assembly provided in another embodiment of this utility model;

[0028] Figure 11 This is a schematic diagram of the cross-sectional structure of a battery assembly provided in one embodiment of the present invention;

[0029] Figure 12 This is a schematic diagram of the cross-sectional structure of a battery assembly provided in another embodiment of the present invention.

[0030] Explanation of key component symbols: 1000, photovoltaic system; 100, battery module; 10, battery cell; 20, grid structure; 30, connector; 21, main grid; 22, fine grid; 31, connecting layer; 32, conductive layer; 301, alloy interface; 302, non-alloy interface; 321, first conductive part; 322, second conductive part; D1, first dimension; D2, second dimension; 40, front panel; 50, encapsulant film. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present utility model, and should not be construed as limiting the present utility model. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining the present utility model and are not intended to limit the present utility model.

[0032] In the description of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "top", "bottom", "lateral", "longitudinal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0033] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0034] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" 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, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0035] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0036] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0037] Please see Figure 1 The photovoltaic system 1000 in this embodiment of the present invention may include the battery module 100, which may include a plurality of battery cells 10. These battery cells 10 may be connected in series via connectors 30 to form a battery string. The battery strings in the battery module 100 may be connected in series, in parallel, or in a series-parallel combination to achieve current collection and output. For example, the connection between the battery strings may be achieved via busbars.

[0038] The accompanying drawings provided in this application are schematic diagrams, and some elements are not shown in the drawings. The purpose is to clearly describe the technical solution and highlight the key features of the utility model. It is not intended to limit the technical solution to exclude these unshown elements. That is to say, the drawings are merely examples and do not represent a limitation on the specific form of the battery module 100.

[0039] like Figures 2 to 12 As shown, the battery assembly 100 in this embodiment of the present invention includes: a battery cell 10, the surface of which is provided with a plurality of grid structures 20; a plurality of connectors 30, which are disposed on the side of the grid structures 20 facing away from the battery cell 10, each connector 30 being electrically connected to at least one grid structure 20, the plurality of connectors 30 being arranged at intervals along a first direction, the connectors 30 extending along a second direction, the second direction intersecting the first direction.

[0040] The connector 30 includes a conductive layer 32 and a connecting layer 31. The connecting layer 31 is wrapped around the outer surface of the conductive layer 32. The connecting layer 31 of each connector 30 forms an alloy interface 301 with at least one grid structure 20. The maximum dimension of the connector 30 in a first direction is a first dimension D1, and the maximum dimension of the connector 30 in a third direction is a second dimension D2. The ratio of the first dimension D1 to the second dimension D2 is 5.5 to 22.5. The third direction is the same as the thickness direction of the battery assembly 100.

[0041] Thus, in this embodiment of the present invention, the battery assembly 100, by setting the ratio of the maximum dimension of the connector 30 in the first direction to the maximum dimension of the connector 30 in the third direction to be 5.5 to 22.5, can increase the contact area between the connector 30 and the battery cell 10, thereby improving the connection stability of the connector 30, and further improving the structural stability and efficiency of the battery assembly 100.

[0042] The types of solar cells 10 in this embodiment include, but are not limited to, passivated emitter rear cell (PERC), tunnel oxide passivated contact (TOPCON), heterojunction with intrinsic thin-layer (HIT), back contact (BC), and perovskite solar cells (PSC). This embodiment does not specifically limit the type of solar cells 10 in the solar module 100.

[0043] Specifically, the battery cell 10 in this application embodiment can be a whole battery cell or a sliced ​​battery cell. A sliced ​​battery cell refers to a battery cell 10 formed by cutting a complete whole battery cell. The cutting process includes: laser grooving + cutting (Linear Spectral Clustering, LSC) process and thermal stress cell separation (TMC) process. In some embodiments, the sliced ​​battery cell can be a half battery cell, which can also be understood as a half-cell or a two-piece battery. In some embodiments, the sliced ​​battery cell can be a 3-piece battery cell, a 4-piece battery cell, or an 8-piece battery cell, etc.

[0044] In some embodiments, the battery assembly 100 includes at least two battery cells 10, and two adjacent battery cells 10 are connected in series via a connector 30 to form a battery string. There can be multiple battery strings, and adjacent battery strings can be connected in series or in parallel via busbars.

[0045] Furthermore, in a battery string, two adjacent battery cells 10 have overlapping areas. This eliminates the spacing between the individual battery cells 10 in the battery string, allowing more battery cells 10 to be placed in the string and improving its utilization efficiency.

[0046] Furthermore, in a battery string, two adjacent battery cells 10 have a first spacing. This allows adjacent battery cells 10 in the battery string to have a certain spacing, preventing them from blocking each other and thus improving the photoelectric conversion efficiency of the battery module 100.

[0047] like Figures 2 to 7 As shown, specifically, in this embodiment, the grid structure 20 is disposed on the surface of the solar cell 10 and is electrically connected to the solar cell 10. The grid structure 20 is used to collect the photocurrent within the solar cell 10 and lead it to the outside of the solar cell 10. Figure 6 and Figure 7 As shown, the solar cell 10 can specifically be a solar cell 10 with a main grid, or, as... Figures 2 to 5 As shown, the solar cell 10 can also be a solar cell 10 without a main grid. When the solar cell 10 is a solar cell 10 with a main grid, the multiple grid line structures 20 include main grids 21 and fine grids 22. When the solar cell 10 is a solar cell 10 without a main grid, the multiple grid line structures 20 only include fine grids 22.

[0048] Specifically, in this embodiment, the connector 30 can be a solder strip, which can be electrically connected to the grid structure 20 provided on the battery cell 10 to realize the interconnection between the battery cells 10 and to collect current and transmit it to the components outside the battery assembly 100.

[0049] Furthermore, the solder ribbon can be a flat solder ribbon. Setting the solder ribbon as a flat solder ribbon allows for reduced film usage and lower raw material costs while maintaining the same conductivity. Moreover, the flat solder ribbon reduces the thickness of the battery module 100, thereby reducing the risk of microcracks and fragmentation of the battery cells 10 within the battery module 100. Simultaneously, using a flat solder ribbon for the connector 30 further increases the contact area between the connector 30 and the battery cells 10, thereby improving the connection stability of the connector 30 and ultimately enhancing the structural stability and efficiency of the battery module 100.

[0050] Furthermore, the cross-sectional shape of the solder strip is at least one of a trapezoidal or rectangular shape, without limitation. Setting the cross-sectional shape of the solder strip to at least one of a trapezoidal or rectangular shape can increase the contact area between the solder strip and the solar cell, thereby improving the connection stability and ultimately improving the structural stability and efficiency of the solar module.

[0051] Furthermore, the connector 30 is disposed on the side of the grid structure 20 facing away from the battery cell 10, each connector 30 is electrically connected to at least one grid structure 20, the plurality of connectors 30 are arranged at intervals along a first direction, the connectors 30 extend along a second direction, and the second direction intersects the first direction.

[0052] like Figures 8 to 12As shown. The connector 30 includes a conductive layer 32 and a connecting layer 31 wrapped around the outer surface of the conductive layer 32. After the connector 30 is welded, the connecting layer 31 can form an alloy interface 301 with the gate structure 20. The alloy interface 301 is specifically the interface between the connecting layer 31 of the connector 30 and the gate structure 20 connected to the connector 30.

[0053] The conductive layer 32 in the connector 30 is a conductive structure with a certain strength and good conductivity. The conductive layer 32 has good conductivity and specifically serves as the main conductive transport layer in the connector 30. The connecting layer 31 can be plated or coated on the surface of the conductive layer 32. The connecting layer 31 can be deposited on the outer surface of the conductive layer 32 using special processes such as electroplating, vacuum deposition, spraying, or hot-dip coating. Specifically, the connecting layer 31 can be uniformly wrapped around the conductive layer 32.

[0054] The connecting layer 31 in the connector 30 can specifically serve as a connecting component in the connector 30, enabling the connector 30 to be connectable and weldable. Through the connecting layer 31 in the connector 30, the connector 30 can be firmly welded to the grid structure 20 of the battery cell 10, thereby conducting the current collected by the grid structure 20.

[0055] Furthermore, the connecting layer 31 is one of a tin-silver alloy connecting layer 31, a tin-copper alloy connecting layer 31, a tin-zinc alloy connecting layer 31, a tin-bismuth alloy connecting layer 31, a tin-lead alloy connecting layer 31, a tin-lead-silver alloy connecting layer 31, or a tin-lead-bismuth alloy connecting layer 31. In this way, the connecting layer 31 can form a low-resistance intermetallic compound with the grid structure 20, which can significantly reduce current transmission losses in the battery module 100, while also possessing excellent resistance to thermal fatigue and corrosion, enabling long-term stable operation in harsh environments (such as high temperature and salt spray), thereby increasing the stability of the battery module 100.

[0056] In other embodiments, the connecting layer 31 may also be a conductive adhesive layer. The conductive adhesive layer has a certain degree of elasticity, and its elastic properties can alleviate thermal expansion stress, prevent microcracks in the battery cell 10, and at the same time simplify the process and reduce equipment investment.

[0057] Furthermore, such as Figure 8As shown, the connector 30 can be a flat solder strip. When the connector 30 is not connected to the grid structure 20 of the battery cell 10, the cross-sectional shape of the connector 30 can be approximately rectangular or trapezoidal, that is, the cross-sectional shape of the solder strip is at least one of trapezoidal or rectangular. Compared with setting the cross-sectional shape of the connector 30 to be circular, the contact area between the connector 30 and the grid structure 20 can be increased, thereby improving the connection stability of the connector 30, reducing cold solder joints, and thus improving the structural stability and efficiency of the battery module 100. Furthermore, the cross-sectional shape of the connector 30 is approximately rectangular or trapezoidal, which can also reduce the thickness of the connector 30, thereby reducing the overall thickness of the battery module 100, and thus reducing the risk of microcracks and fragments in the battery cell 10.

[0058] Understandably, when the connector 30 is connected to the grid structure 20 of the battery cell 10, the interface between the connector 30 and the grid structure 20 to which the connector 30 is connected is an alloy interface 301.

[0059] like Figures 9 to 12 As shown, when the connector 30 is connected to the grid structure 20 of the battery cell 10, the grid structure 20 to which the connector 30 is connected can be alloyed. This makes the interface between the connection layer 31 of the connector 30 and the grid structure 20 connected to the connector 30 an alloy interface. The connection layer 31 includes an alloy interface 301 formed by the grid structure 20 in contact with the connector 30 and a non-alloy interface 302 not in contact with the grid structure connected to the connector 30.

[0060] Specifically, alloying refers to the process of combining two or more metals (or metals and non-metals) through physical or chemical methods to form a homogeneous or heterogeneous material (i.e., an alloy) with new properties. In the manufacturing of the battery module 100, the alloying of the connector 30 and the grid structure 20 refers to the process in which the connector 30 and the metal grid lines on the surface of the battery cell 10 undergo atomic-level diffusion and reaction at high temperatures to form a stable intermetallic compound. The preparation process of the alloy interface 301 formed between the connector layer 31 and the grid structure 20 connected to the connector 30 includes: during the welding process of the connector layer 31, heat is transferred to the connector 30, causing a portion of the connector layer 31 on the surface opposite to the battery cell 10 to molten at a melting temperature. The tin element in the connector layer 31 diffuses with at least one of the silver, copper, zinc, bismuth, and indium elements in the grid structure 20 on the battery cell 10 to form an alloy, which serves as the connector layer 31.

[0061] The preparation process of the non-alloy interface 302 formed in the connecting layer 31 that is not in contact with the gate line structure 20 connected to the connector 30 includes: during the formation of the connecting layer 31, the connecting layer 31, which is wrapped by the isolation layer or the adhesive film, does not melt, or the molten connecting layer 31 is wrapped by the isolation layer, ultimately forming the non-alloy interface 302 that is not in contact with the gate line structure 20. That is, the portion of the connecting layer 31 that is not alloyed with the gate line structure 20. In some embodiments, the area of ​​the alloy interface 301 of the connecting layer in a connector 30 is substantially the same as the area of ​​the non-alloy interface 302.

[0062] Specifically, during the connection process between the connector 30 and the gate line structure 20, the connecting layer 31 of the connector 30 will melt due to heat, making the connecting layer 31 and the gate line structure 20 electrically connected and forming a stable ohmic contact. Furthermore, the conductive layer 32 encased by the connecting layer 31 will not melt. Finally, after cooling, the connector 30 and the gate line structure 20 form a stable ohmic contact. Figures 9 to 12 The cross-sectional connection structure is shown.

[0063] After the connector 30 is connected to the gate structure 20, the part of the connector 30 where the connecting layer 31 contacts the gate structure 20 is the alloy interface 301. The alloy interface 301 can be a tin-silver alloy metal compound, a tin-copper alloy metal compound, a tin-zinc alloy metal compound, a tin-bismuth alloy metal compound, or a tin-indium alloy metal compound, etc.

[0064] like Figure 9 As shown, specifically, the maximum or average dimension of the connector 30 in the first direction is the first dimension D1, and the maximum or average dimension of the connector 30 in the third direction is the second dimension D2. The ratio of the first dimension D1 to the second dimension D2 is 5.5 to 22.5. For example, it is 5.5, 6, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 15, 15.5, 16.5, 16.7, 18, 20, 21.5, or 22.5.

[0065] The table below shows the specific values ​​of the first dimension D1 and the second dimension D2 of the connector 30 in some embodiments, as well as the specific value of the ratio of the first dimension D1 to the second dimension D2. In this table, the maximum dimension of the connector 30 in the first direction is the first dimension D1, the maximum dimension of the connector 30 in the third direction is the second dimension D2, and the ratio of the first dimension D1 to the second dimension D2 is 5.5 to 22.5. For example, 5.5, 6, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12.1, 12.5, 13, 15, 15.5, 16.5, 16.7, 18, 20.1, 20.4, 21.5, and 22.5. The first dimension D1, the second dimension D2, and the ratio of the first dimension D1 to the second dimension D2 in the table below are only partial examples. It is understood that those skilled in the art can set the dimensions and ratios according to the actual situation, and no limitation is made here.

[0066] Serial Number First size D1 Second size D2 The ratio of the first dimension D1 to the second dimension D2 1 2.45mm 0.12mm 20.4 2 2.81mm 0.14mm 20.1 3 1.57mm 0.13mm 12.1 4 1.23mm 0.13mm 9.5 5 1.55mm 0.26mm 6.0

[0067] In some embodiments, it is understood that the first dimension D1 specifically refers to the maximum dimension of the connector 30 in the first direction after it is disposed in the battery assembly 100 and connected to the grid structure 20. That is, when the connector 30 is irregularly shaped, the maximum dimension of the cross-section of the connector 30 along the third direction in the first direction is the first dimension D1. In some embodiments, the maximum dimension of the alloy interface 301 formed by the connecting layer 31 and the grid structure 20 connected to the connector 30 in the first direction is the first dimension D1.

[0068] It is understood that the second dimension D2 specifically refers to the maximum dimension of the connector 30 in the third direction after it is disposed in the battery assembly 100 and connected to the grid structure 20. That is, when the connector 30 is irregularly shaped, the maximum dimension of the cross-section of the connector 30 along the third direction in the third direction is the second dimension D2. In some embodiments, when the connecting layer 31 and the grid structure 20 connected to the connector 30 form an alloy interface 301, the second dimension D2 is the maximum dimension of the connector 30 in the third direction, including the alloy interface 301.

[0069] like Figure 10As shown, in one possible implementation, the average dimension of the connector 30 in the first direction is a third dimension D3, and the average dimension of the connector 30 in the third direction is a fourth dimension D4. The ratio of the third dimension D3 to the fourth dimension D4 is 5.5 to 22.5, that is, the third dimension D3 is the average dimension of the connector 30 in the first direction, and is taken as the first dimension D1. The fourth dimension D4 is the average dimension of the connector 30 in the third direction, and is taken as the second dimension D2. In the battery assembly 100 of this utility model embodiment, by setting the ratio of the average dimension of the connector 30 in the first direction to the average dimension of the connector 30 in the third direction to 5.5 to 22.5, the contact area between the connector 30 and the battery cell 10 can be increased, thereby improving the connection stability of the connector 30, and thus improving the structural stability and efficiency of the battery assembly 100.

[0070] It is understandable that the third dimension D3 specifically refers to the average dimension of the connector 30 in the first direction after it is installed in the battery assembly 100 and connected to the grid structure 20. That is, when the connector 30 is irregularly shaped, the equivalent length value obtained by multi-point sampling and measurement of the connector 30 along the third direction section in the first direction and the arithmetic mean is the third dimension D3.

[0071] It is understandable that the fourth dimension D4 specifically refers to the average dimension of the connector 30 in the third direction after it is installed in the battery assembly 100 and connected to the grid structure 20. That is, when the connector 30 is irregular in shape, the equivalent length value obtained by multi-point sampling measurement of the connector 30 along the third direction section and the arithmetic mean is the fourth dimension D4.

[0072] like Figure 10 As shown, specifically, the average dimension of the connector 30 in the first direction is the third dimension D3, and the average dimension of the connector 30 in the third direction is the fourth dimension D4. The ratio of the third dimension D3 to the fourth dimension D4 is 5.5 to 22.5. For example, it is 5.5, 6.6, 7.9, 9.8, 8.5, 9, 9.5, 10, 10.5, 11, 11.8, 12, 12.5, 13, 14.8, 15, 15.5, 16.5, 16.7, 18, 20, 21.5, or 22.5.

[0073] The table below shows the specific values ​​of the third dimension D3 and the fourth dimension D4 of the connector 30 in some embodiments, as well as the specific value of the ratio of the third dimension D3 to the fourth dimension D4. The first dimension D1, the second dimension D2, and the ratio of the first dimension D1 to the second dimension D2 in the table below are only partial examples. It is understood that those skilled in the art can set the dimensions and ratios according to the actual situation, and no limitation is made here.

[0074] Serial Number Third size D3 Fourth size D4 The ratio of the third dimension D3 to the fourth dimension D4 1 1.63mm 0.11mm 14.8 2 1.65mm 0.14mm 11.8 3 1.37mm 0.14mm 9.8 4 1.03mm 0.13mm 7.9 5 1.05mm 0.16mm 6.6

[0075] Furthermore, when the connector 30 is connected to the grid structure 20 of the battery cell 10, the cross-sectional shape of the connector 30 is as follows: Figures 9 to 12 The irregular morphology shown.

[0076] Further, the first direction specifically refers to the direction in which the connectors 30 are spaced apart, the second direction specifically refers to the extension direction of the connectors 30, and the third direction specifically refers to the same as the thickness direction of the battery assembly 100. In some embodiments, the third direction can be set to be perpendicular to both the first and second directions, and the first and second directions can also be perpendicular to each other. Alternatively, the first, second, and third directions can be set to intersect each other at a certain angle. This utility model does not impose any limitations on this.

[0077] In this embodiment, the ratio of the first dimension D1 to the second dimension D2 of the connector 30 is 5.5 to 22.5. Compared with the smaller ratio of the first dimension D1 to the second dimension D2 in the circular solder strip, the contact area between the connector 30 and the grid structure 20 is small. In this embodiment, the ratio of the first dimension D1 to the second dimension D2 is increased, thereby increasing the contact area between the connector 30 and the battery cell 10, so that the connector 30 and the battery cell 10 form a stable conductive connection, thereby improving the structural stability and efficiency of the battery assembly 100.

[0078] In one possible implementation, such as Figures 8 to 12 As shown, the conductive layer 32 includes a first conductive portion 321 and a second conductive portion 322. The second conductive portion 322 wraps around the outer surface of the first conductive portion 321, and the connecting layer 31 wraps around the outer surface of the second conductive portion 322. The materials of the first conductive portion 321 and the second conductive portion 322 are different. This allows the first conductive portion 321 and the second conductive portion 322 in the conductive layer 32 to be made of different materials, thereby increasing the flexibility in the fabrication of the conductive layer 32. In different application scenarios, the material combination and structural parameters of each part of the conductive layer 32 can be flexibly adjusted to achieve targeted optimization.

[0079] Understandably, the conductivity of the second conductive part 322 can be set to be greater than that of the first conductive part 321, so that the outer layer of the connector 30 has good conductivity, ensuring the connection quality and conductivity at the contact point between the connector 30 and the battery cell 10, without affecting the overall electrical performance. Furthermore, the cost of the first conductive part 321 can be set to be lower than that of the second conductive part 322, thereby effectively reducing the manufacturing cost of the connector 30.

[0080] Furthermore, the second conductive part 322 is one of a copper conductive part, a silver conductive part, or a gold conductive part. In this way, by setting the second conductive part 322 to copper, aluminum, or gold, which have good conductivity, the conductivity of the connector 30 can be increased, and a good conductive connection can be achieved between the connector 30 and the battery cell 10.

[0081] Furthermore, the first conductive part 321 is either an aluminum conductive part or a nickel conductive part. In this way, by setting the second conductive part 322 to be made of copper, aluminum, or gold, which have lower costs, the manufacturing cost of the connector 30 can be reduced.

[0082] Furthermore, the second conductive part 322 can be one of a copper conductive part, a silver conductive part, or a gold conductive part. And the first conductive part 321 can be one of an aluminum conductive part or a nickel conductive part. In this way, the manufacturing cost of the connector 30 can be reduced while ensuring good conductivity of the connector 30.

[0083] Preferably, the first conductive part 321 can be set as an aluminum conductive part and the second conductive part 322 can be set as a copper conductive part. In this way, the manufacturing cost of the connector 30 can be effectively reduced while ensuring the conductivity of the connector 30.

[0084] In one possible implementation, such as Figure 6 and Figure 7 As shown, the solar cell 10 is a solar cell with a main grid. Multiple grid structures 20 include main grids 21 and fine grids 22. The connection layer 31 of each connector 30 forms an alloy interface 301 with one main grid 21 of the solar cell 10. This allows each main grid 21 of the solar cell 10 to form a stable conductive connection with the connector 30, thereby ensuring the stability and reliability of the current transmitted through the main grid 21. Furthermore, by forming the alloy interface 301 between the connection layer 31 and the main grid 21, not only is contact resistance reduced, but welding strength and interface stability are also enhanced, improving the long-term reliability of the solar module 100 under thermal cycling and environmental aging conditions.

[0085] In one possible implementation, such as Figure 4 and Figure 5As shown, the solar cell 10 is a gridless solar cell 10. Multiple grid structures 20 include multiple fine grids 22. The connecting layer 31 of each connector 30 forms an alloy interface 301 with the multiple fine grids 22 of the solar cell 10. That is, the extension directions of each connector 30 and the multiple fine grids 22 of the solar cell 10 are intersected. Specifically, the multiple fine grids 22 are intersected and spaced apart in a second direction and extend along a first direction, while the multiple connectors are intersected and spaced apart in the first direction and extend along a second direction. In this case, the first and second directions can be perpendicular to each other. This allows multiple fine grids 22 to simultaneously form a stable and uniform conductive connection with the connectors 30, which helps to disperse the current transmission path, reduce local current density, thereby reducing resistance loss and heat generation, and improving the overall conductivity and thermal stability of the solar cell assembly 100.

[0086] In one possible implementation, such as Figure 2 and Figure 3 As shown, the solar cell 10 is a gridless solar cell 10. Multiple grid structures 20 include multiple fine grids 22. The connecting layer 31 of each connector 30 forms an alloy interface 301 with one fine grid 22 of the solar cell 10. That is, the extension direction of each connector 30 is parallel to the extension direction of the multiple fine grids of the solar cell 10. Specifically, the multiple fine grids 22 are arranged at intervals in a first direction and extend along a second direction, and the multiple connectors are arranged at intervals in the first direction and extend along the second direction. In this case, the first and second directions can be perpendicular to each other. This helps to achieve a one-to-one conductive connection between the fine grids 22 and the connectors 30, ensuring a clear and stable current transmission path, reducing the contact resistance between the fine grids 22 and the connectors 30, and improving the mechanical strength and conductive reliability of the welded interface. Furthermore, the multiple fine grids 22 are uniformly distributed on the surface of the solar cell 10, and each connector 30 is connected to a different fine grid 22, which can effectively disperse the current-carrying pressure, improve the overall current carrying capacity and resistance to local failures of the solar cell 100, thereby enhancing the operational stability and long-term reliability of the solar cell 100.

[0087] It is understandable that, such as Figures 9 to 12 As shown, in such an embodiment, the battery assembly 100 may further include a frame, a front panel 40, a back panel, photovoltaic glass, and an encapsulating film 50. The encapsulating film 50 may be filled between the front and back of the battery cells 10, as well as between the photovoltaic glass and adjacent battery cells 10. As a filler, it may be a transparent colloid with good light transmittance and aging resistance. For example, the encapsulating film 50 may be an EVA encapsulating film 50 or a POE encapsulating film 50. The specific choice can be made according to the actual situation and is not limited here.

[0088] Photovoltaic glass can be applied to the encapsulating film 50 on the front side of the solar cell 10. The photovoltaic glass can be ultra-clear glass, which has high light transmittance, high transparency, and superior physical, mechanical, and optical properties. For example, ultra-clear glass can have a light transmittance of over 92%, protecting the solar cell 10 while minimizing impact on its efficiency. Simultaneously, the encapsulating film 50 bonds the photovoltaic glass and the solar cell 10 together, providing sealing, insulation, and waterproofing / moisture protection for the solar cell 10.

[0089] The backsheet can be attached to the adhesive film 50 on the back of the solar cell 10. The backsheet protects and supports the solar cell 10, and has reliable insulation, water resistance, and aging resistance. Multiple options are available for the backsheet, typically tempered glass, acrylic glass, aluminum alloy TPT composite adhesive film 50, etc. The specific choice depends on the specific circumstances and is not limited here. The backsheet, solar cell 10, adhesive film 50, and photovoltaic glass can be integrated into a frame. The frame serves as the main external support structure for the entire solar module 100, providing stable support and installation for the solar module 100. For example, the solar module 100 can be installed at the desired location via the frame.

[0090] In the description of this specification, the references to terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an 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.

[0091] Furthermore, the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery assembly, comprising: include: A solar cell, wherein the surface of the solar cell is provided with multiple grid line structures; Multiple connectors are disposed on the side of the grid structure facing away from the battery cell. Each connector is electrically connected to at least one grid structure. The multiple connectors are spaced apart along a first direction and extend along a second direction, which intersects the first direction. The connector includes a conductive layer and a connecting layer, the connecting layer being wrapped around the outer surface of the conductive layer, and the connecting layer of each connector forming an alloy interface with at least one of the grid structures; the maximum or average size of the connector in the first direction is a first size, the maximum or average size of the connector in a third direction is a second size, the ratio of the first size to the second size is 5.5 to 22.5, and the third direction is the same as the thickness direction of the battery assembly.

2. The battery assembly of claim 1, wherein, The conductive layer includes a first conductive portion and a second conductive portion, the second conductive portion is wrapped around the outer surface of the first conductive portion, the connecting layer is wrapped around the outer surface of the second conductive portion, and the material of the first conductive portion is different from the material of the second conductive portion.

3. The battery assembly of claim 2, wherein, The second conductive part is one of copper conductive part, silver conductive part or gold conductive part.

4. The battery assembly according to claim 2, characterized in that, The first conductive part is either an aluminum conductive part or a nickel conductive part.

5. The battery assembly according to claim 2, characterized in that, The conductivity of the second conductive part is greater than that of the first conductive part.

6. The battery assembly according to claim 1, characterized in that, The connecting layer is one of the following: tin-silver alloy connecting layer, tin-copper alloy connecting layer, tin-zinc alloy connecting layer, tin-bismuth alloy connecting layer, tin-indium alloy connecting layer, tin-lead alloy connecting layer, tin-lead-silver alloy connecting layer, or tin-lead-bismuth alloy connecting layer.

7. The battery assembly according to claim 1, characterized in that, The solar cell is a solar cell with a main grid, and the plurality of grid structures include a main grid and fine grids. The connecting layer of each connector forms an alloy interface with one of the main grids of the solar cell.

8. The battery assembly according to claim 1, characterized in that, The solar cell is a gridless solar cell, and the plurality of grid structures include a plurality of fine grids. The connecting layer of each connector forms an alloy interface with the plurality of fine grids of the solar cell.

9. The battery assembly according to claim 1, characterized in that, The solar cell is a gridless solar cell, and the plurality of grid structures include a plurality of fine grids. The connecting layer of each connector forms an alloy interface with one of the fine grids of the solar cell.

10. The battery assembly according to claim 1, characterized in that, The connector is a welding strip, and the welding strip is a flat welding strip.

11. The battery assembly according to claim 10, characterized in that, The cross-sectional shape of the welding strip is at least one of trapezoidal or rectangular.

12. A photovoltaic system, characterized in that, Includes the battery assembly as described in any one of claims 1 to 11.

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