Battery piece and photovoltaic module

Abstract

The invention relates to the technical field of solar cells, in particular to a cell piece and a photovoltaic module. The battery piece comprises a body, a bonding pad, a harpoon structure and a fine grid. The bonding pad comprises an edge bonding pad and a middle bonding pad, and the middle bonding pad is located on one side of the edge bonding pad in the first direction. In the first direction, the harpoon structure is located on the side, away from the middle bonding pad, of the edge bonding pad, and the harpoon structure comprises a harpoon gap. A first fine grid and a second fine grid are arranged on the side, away from the middle bonding pad, of the edge bonding pad, and the first fine grid is located between the second fine grid and the edge bonding pad. The first fine grids are disconnected at the fish fork gaps, and the second fine grids penetrate through the fish fork gaps along the second direction, thereby optimizing the current collection path, facilitating the reduction of the current transmission loss, and improving the output power of the battery piece.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to a cell and a photovoltaic module. Background Art

[0002] The cell consists of a main grid and fine grids, extending in orthogonal directions. The main grid is equipped with pads for welding to the ribbons, thereby collecting and transmitting current. A harpoon structure is provided at the end of the main grid, and some fine grids are electrically connected to the harpoon structure to collect current from these fine grids.

[0003] Typically, the fine grid connected to the harpoon structure will penetrate the harpoon structure, causing the current collection path of the battery cell to deteriorate, thereby affecting the efficiency of the battery cell.

[0004] Therefore, how to optimize the current collection path of the battery cell is an important issue that needs to be solved in this field. Summary of the Invention

[0005] In view of this, the present application provides a solar cell and a photovoltaic module that can optimize the current collection path of the solar cell.

[0006] The first aspect of the present application provides a battery cell, comprising a body, a solder pad, a harpoon structure and a fine grid. A plurality of solder pads are arranged along a first direction, the solder pads including an edge solder pad located on the outermost side in the first direction, and the solder pads also including a middle solder pad, and in the first direction, the middle solder pad is located on one side of the edge solder pad. The body also includes a light-facing surface and a backlight surface distributed along the thickness direction of the battery cell, and at least one of the light-facing surface and the backlight surface is provided with a harpoon structure, and in the first direction, the harpoon structure is located on the side of the edge solder pad away from the middle solder pad, and the harpoon structure includes a harpoon gap. The fine grid includes a first fine grid and a second fine grid, and in the first direction, the first fine grid and the second fine grid are both located on the side of the edge solder pad away from the middle solder pad, and the first fine grid is located between the second fine grid and the edge solder pad. The first fine grid and the second fine grid are both connected to the harpoon structure, the first fine grid is disconnected at the harpoon gap, and the second fine grid passes through the harpoon gap along the second direction.

[0007] In the present application, the current on the first fine grid and the second fine grid can be transmitted to the edge pad through the harpoon structure, and then transmitted to the welding strip through the edge pad, so as to realize the collection and transmission of the current on the first fine grid and the second fine grid, thereby improving the collection efficiency of the current at the edge of the battery cell and increasing the output power of the battery cell.

[0008] The first fine grid is disconnected at the harpoon structure, which reduces the slurry required for the first fine grid and the material cost of the first fine grid, thereby helping to reduce the cost of the battery cell.

[0009] The second fine grid runs through the harpoon structure, that is, the second fine grid is not disconnected at the harpoon structure, which optimizes the current collection path, helps to reduce current transmission loss, and improves the output power of the battery cell.

[0010] In some possible designs, the number of the first fine gates arranged in the first direction is N1, where 1≤N1≤10.

[0011] In some possible designs, in the first direction, the cell includes an outermost edge fine grid, and the second fine grid is configured as an edge fine grid.

[0012] In some possible designs, the fine grid further includes a third fine grid, which is located on a side of the second fine grid away from the first fine grid in the first direction, is connected to the harpoon structure, and is disconnected at the harpoon gap.

[0013] In some possible designs, the number of the third fine gates arranged in the first direction is N2, where 1≤N2≤10.

[0014] In some possible designs, the body includes a first edge and a second edge arranged along a first direction, and the edge pads include the first edge pad and the second edge pad arranged along the first direction, wherein the first edge pad is located between the first edge and the second edge pad in the first direction. In the first direction, a harpoon structure, a first fine grid, and a second fine grid are disposed between the first edge pad and the first edge, and a harpoon structure, a first fine grid, and a second fine grid are disposed between the second edge pad and the second edge.

[0015] In some possible designs, the body includes a first edge and a second edge arranged along a first direction, and the edge pad includes a first edge pad and a second edge pad arranged along the first direction, wherein the first edge pad is located between the first edge and the second edge pad in the first direction. In the first direction, a harpoon structure is provided between the first edge pad and the first edge, and between the second edge pad and the second edge. In the first direction, the first fine grid and the second fine grid are located between the first edge pad and the first edge. The fine grid further includes a fourth fine grid, wherein the fourth fine grid is located between the second edge pad and the second edge in the first direction, the fourth fine grid is connected to the harpoon structure, and the fourth fine grid extends through the harpoon gap in the second direction.

[0016] In some possible designs, the fine grid further includes a fifth fine grid, wherein in the first direction, the fifth fine grid is located between the fourth fine grid and the second edge, and the fifth fine grid is connected to the harpoon structure and is disconnected at the harpoon gap.

[0017] In some possible designs, the number of the fifth fine gates arranged in the first direction is N3, where 1≤N3≤10.

[0018] In some possible design, the middle pads include main pads and auxiliary pads, the main pads are arranged along the first direction, and at least two auxiliary pads are arranged between two adjacent main pads, and the projection area of the main pad is larger than that of the auxiliary pad in the thickness direction of the battery piece.

[0019] In some possible design, the width of the main pad in the second direction is W1, the width of the auxiliary pad in the second direction is W2, and W2 < W1. 1 mm ≤ W1 ≤ 3.5 mm, and 0.3 mm ≤ W2 ≤ 1.2 mm.

[0020] In some possible design, in the first direction, at least three auxiliary pads are arranged between the edge pad and the main pad adjacent to the edge pad.

[0021] In some possible design, the contour shape of the main pad is circular or rectangular, and the contour shape of the auxiliary pad is T-shaped, H-shaped or Z-shaped.

[0022] In some possible design, in the first direction, the number of the thin grids between two adjacent pads is 0, or at least one thin grid is arranged between two adjacent pads. The pads and the thin grids are periodically arranged in the first direction.

[0023] In some possible design, in the first direction, the number of the thin grids between two adjacent pads is 0. The middle pads include main pads and auxiliary pads, and the projection area of the main pad is larger than that of the auxiliary pad in the thickness direction of the battery piece. The thin grids include main thin grids and auxiliary thin grids, the end of the main thin grid is in contact with the main pad, and the end of the auxiliary thin grid is in contact with the auxiliary pad. In the first direction, the distance between the main thin grid and the auxiliary thin grid adjacent to the main thin grid is L1, and the distance between two adjacent auxiliary thin grids is L2, and 0.3 ≤ L1 / L2 ≤ 7.

[0024] In some possible design, 0.5 mm ≤ L1 ≤ 2 mm, 0.3 mm ≤ L2 ≤ 1.5 mm, and L2 < L1.

[0025] In some possible design, the battery piece is a main grid-free battery piece, and the pads are directly connected with the thin grids.

[0026] In some possible design, the battery piece further includes main grids extending along the first direction, the thin grids are connected with the main grids, and at least part of the pads are located on the main grids. The main grids are arranged at intervals along the second direction, and the number of the main grids in the second direction is N4, and 5 ≤ N4 ≤ 24.

[0027] In some possible design, the pads arranged along the first direction form a pad column, and a plurality of pad columns are arranged along the second direction. In the second direction, the number of the main grids is the same as that of the pad columns. Alternatively, in the second direction, the number of the main grids is less than that of the pad columns, and at least one pad column is arranged between two adjacent main grids.

[0028] In some possible designs, the cell further includes a main grid extending along the first direction, the fine grid is connected to the main grid, and at least some of the pads are located on the main grid. The number of main grids in the first direction is one, or multiple main grids are arranged at intervals along the first direction.

[0029] A second aspect of the present application provides a photovoltaic module, comprising a cover plate, an encapsulation layer and a battery layer, wherein the battery layer comprises a plurality of battery cells as described in any one of the above items.

[0030] It should be understood that the foregoing general description and the following detailed description are merely illustrative and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0032] Figure 1 A schematic diagram of the structure of the battery cell provided in this application in some embodiments;

[0033] Figure 2 Schematic diagram of the structure of the battery cell provided in this application in other embodiments;

[0034] Figure 3 Schematic diagram of the structure of the battery cell provided in this application in some other embodiments;

[0035] Figure 4 A schematic diagram of the partial structure of the battery cell provided in this application in some embodiments;

[0036] Figure 5 Schematic diagram of the partial structure of the battery cell provided in this application in some other embodiments;

[0037] Figure 6 for Figure 5 An enlarged view of part A in some embodiments;

[0038] Figure 7 for Figure 5 An enlarged view of part A in other embodiments;

[0039] Figure 8 for Figure 5 An enlarged view of part A in some other embodiments;

[0040] Figure 9 for Figure 5A partial structural schematic view of the battery piece in some embodiments of the present application;

[0041] Figure 10 A partial structural schematic view of the battery piece in some embodiments of the present application; Figure 5 An enlarged view of part B in some embodiments of the present application;

[0042] Figure 11 A partial structural schematic view of the battery piece in some embodiments of the present application; Figure 5 An enlarged view of part B in some embodiments of the present application;

[0043] Figure 12 A partial structural schematic view of the battery piece in some embodiments of the present application;

[0044] Figure 13 A partial structural schematic view of the battery piece in some embodiments of the present application;

[0045] Figure 14 A partial structural schematic view of the battery piece in some embodiments of the present application;

[0046] Figure 15 An enlarged view of part C in some embodiments of the present application; Figure 5

[0047] An enlarged view of part C in some embodiments of the present application; Figure 16 Figure 5 An enlarged view of part D in some embodiments of the present application;

[0048] Figure 17 Figure 5 An enlarged view of part C in some embodiments of the present application;

[0049] Figure 18 An enlarged view of part C in some embodiments of the present application; Figure 5

[0050] A partial structural schematic view of the battery piece in some embodiments of the present application; Figure 19

[0051] An enlarged view of part E in some embodiments of the present application; Figure 20 Figure 19 A partial structural schematic view of the battery piece in some embodiments of the present application;

[0052] Figure 21 A partial structural schematic view of the battery piece in some embodiments of the present application;

[0053] Figure 22 Figure 21 An enlarged view of part C in some embodiments of the present application;

[0054] Figure 23 An enlarged view of part C in some embodiments of the present application; Figure 21 ​​​​Schematic diagram of the connection structure of the battery layers in some embodiments.

[0055] Reference numerals:

[0056] 10 - cover plate; 101 - first cover plate; 102 - second cover plate; 20 - packaging layer; 201 - first adhesive film; 202 - second adhesive film; 30 - battery layer; 301 - battery cell; 302 - solder ribbon; 303 - bus bar; 304 - whole cell; 305 - two-cell cell; 306 - three-cell cell;

[0057] 1-body; 11-first edge; 12-second edge;

[0058] 2-pad; 21-edge pad; 211-first edge pad; 212-second edge pad; 22-middle pad; 221-main pad; 222-secondary pad; 23-pad column;

[0059] 3- harpoon structure; 31- first confluence; 32- second confluence; 33- harpoon gap;

[0060] 4 - fine grid; 41 - first fine grid; 411 - first section; 412 - second section; 42 - second fine grid; 43 - third fine grid; 431 - third section; 432 - fourth section; 44 - fourth fine grid; 45 - fifth fine grid; 451 - fifth section; 452 - sixth section; 46 - edge fine grid; 47 - middle fine grid; 48 - main fine grid; 49 - auxiliary fine grid;

[0061] 5-main grid; X-second direction; Y-first direction; Z-third direction. DETAILED DESCRIPTION

[0062] In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0063] It should be clear that the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0064] The terms used in the embodiments of the present application are for the purpose of describing specific embodiments only and are not intended to limit the present application. The singular forms "a", "an", "the" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0065] It should be understood that the term "and / or" as used herein simply describes a relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A alone, A and B together, or B alone. Furthermore, the character " / " in this document generally indicates an "or" relationship between the associated objects.

[0066] According to a first aspect of an embodiment of the present application, a battery cell is provided, and the types of battery cells include but are not limited to Passivated Emitter Rear Cell (PERC), Tunnel Oxide Passivated Contact (TOPCon), Heterojunction with Intrinsic Thin-film (HJT), Interdigitated Back Contact (IBC), perovskite battery, etc.

[0067] A PERC cell, along its thickness, consists of a front-surface silver electrode, a front-surface silicon nitride passivation layer, a phosphorus emitter layer, a P-type silicon substrate layer, a partial aluminum back field, a metal aluminum back electrode, and a back passivation layer (Al2O3 / SiNx). PERC cells use a passivation film on the back side, replacing a full aluminum back field. This enhances internal back reflection of light from the silicon substrate, reduces the back recombination rate, and increases cell efficiency by 0.5%-1%.

[0068] For TOPCon cells, along their thickness, they consist of a metallic silver electrode, a front-surface silicon nitride passivation layer, a boron-doped emitter, an N-type base silicon layer, a diffused doped layer, ultra-thin silicon oxide, doped polysilicon, silicon nitride, and a metallic silver electrode. The back of the cell is composed of an ultra-thin silicon oxide layer (1nm to 2nm) and a phosphorus-doped microcrystalline amorphous mixed Si film, which together form a passivated contact structure. This structure can block minority carrier-hole recombination, thereby increasing the cell's open-circuit voltage and short-circuit current. The ultra-thin oxide layer allows majority electrons to tunnel into the polysilicon layer while blocking minority carrier-hole recombination. The excellent passivation effect of the ultra-thin silicon oxide and heavily doped silicon film causes the energy bands on the silicon wafer to bend, thereby forming a field passivation effect. This significantly increases the probability of electron tunneling, reduces contact resistance, and increases the cell's open-circuit voltage and short-circuit current, thereby improving the cell's conversion efficiency.

[0069] For HJT cells, along their thickness direction, the HJT cells include a front low-temperature silver electrode, a front conductive film, an N-type amorphous silicon film, an intrinsic amorphous silicon film, an N-type base silicon layer, an intrinsic amorphous silicon film, a P-type amorphous silicon film, a back conductive film, and a back low-temperature silver electrode.

[0070] An IBC cell, along its thickness, consists of a silicon nitride inversion layer, an N+ front surface field, an N-type base silicon layer, a P+ emitter, an N+ back field, an aluminum oxide passivation layer, a silicon nitride anti-reflection layer, and a silver electrode. IBC cells utilize ion implantation technology to achieve uniform P and N regions with precisely controlled junction depths. The front of the cell is free of grid lines, eliminating current losses from metal electrode shading and maximizing the utilization of incident photons. This improves short-circuit current by approximately 7% compared to conventional solar cells. Due to the back-contact structure, grid line shading is not a concern, allowing for a wider grid line ratio, reducing series resistance and achieving a high fill factor. Optimized surface passivation and light-trapping structures enable a low front-surface recombination rate and surface reflection.

[0071] A perovskite cell, along its thickness, consists of a substrate material, a conductive film, an electron transport layer (titanium dioxide), a perovskite absorption layer (hole transport layer), and a metal cathode. Perovskite materials have a high light absorption coefficient and a long carrier diffusion distance. After photons absorbed by the perovskite material are converted into electrons, they are easily collected by the electrode with minimal loss. This results in a high photogenerated voltage and current, giving perovskites high photoelectric conversion efficiency.

[0072] The following describes the specific structure of the battery cell in detail by taking the TOPCon battery cell as an example.

[0073] Figure 1 This is a schematic diagram of the structure of the battery cell provided in this application in some embodiments. Figure 1 As shown, in some embodiments, the battery cell is a whole battery cell 304 . In this case, the first edge 11 and the second edge 12 of the battery cell are both non-cut edges, and chamfers are provided at the first edge 11 and the second edge 12 .

[0074] Figure 2 This is a schematic diagram of the structure of the battery cell provided in this application in some embodiments. Figure 2 As shown, in other embodiments, the battery cell is a two-piece battery 305, that is, the whole battery 304 is connected along the Figure 2 The dotted line in the figure is cut into two halves, and one of the halves is taken to make a two-piece battery 305. At this time, one of the first edge 11 and the second edge 12 of the battery cell is a non-cutting edge, and the other is a cutting edge. The non-cutting edge is chamfered, and the cutting edge is not chamfered.

[0075] Figure 3 This is a schematic diagram of the structure of the battery cell provided in this application in some embodiments. Figure 3As shown, in some other embodiments, the battery cell is a three-piece battery 306 or other multi-piece battery. Taking the battery cell as a three-piece battery 306 as an example, the whole battery 304 is connected along the Figure 3 The dotted line in the figure is cut into three pieces, and one of the pieces is used to make a three-piece battery 306. In this case, one of the first edge 11 and the second edge 12 of the battery cell is a non-cut edge, and the other is a cut edge. The non-cut edge is chamfered, while the cut edge is not. Alternatively, both the first edge 11 and the second edge 12 are cut edges, and neither of the first edge 11 and the second edge 12 is chamfered.

[0076] The embodiments of the present application do not impose any special restrictions on the specific type of battery cell, that is, the battery cell can be a whole cell, a two-cell cell, a three-cell cell, or other multi-cell cells.

[0077] Figure 4 is a schematic diagram of the local structure of a battery cell in some embodiments, Figure 4 The example shows that the battery cell is a whole battery cell, and the first edge 11 and the second edge 12 of the battery cell are both non-cut edges.

[0078] Figure 5 is a schematic diagram of the local structure of a battery cell in some embodiments, Figure 5 The example shows that the battery cell is a two-piece battery, the first edge 11 is a cutting edge, and the second edge 12 is a non-cutting edge.

[0079] The following describes the specific structure of the battery cell in detail by taking a two-piece battery cell as an example.

[0080] like Figure 5 As shown, the battery cell includes a main body 1, which includes a light-facing surface and a backlight surface arranged along its own thickness direction, wherein the light-facing surface refers to the side of the main body 1 facing the sunlight when the back-contact battery is in working condition, and the backlight surface refers to the side of the main body 1 facing away from the sunlight when the back-contact battery is in working condition. The light-facing surface can also be understood as the upper surface of the main body 1, and the backlight surface can be understood as the lower surface of the main body 1.

[0081] like Figure 5 As shown, both the light-facing surface and the backlight surface of the main body 1 are provided with fine grids 4 extending along the second direction X, and multiple fine grids 4 are arranged along the first direction Y, and the polarity of the fine grids 4 on the light-facing surface is opposite to that of the fine grids 4 on the backlight surface. Exemplarily, the fine grids 4 on the light-facing surface are positive fine grids, and the fine grids 4 on the backlight surface are negative fine grids.

[0082] Among them, the first direction Y and the second direction X are both perpendicular to the thickness direction of the body 1. For example, one of the first direction Y and the second direction X is the length direction of the body 1, and the other is the width direction of the body 1. The thickness direction of the body 1 is recorded as the third direction Z, then the first direction Y, the second direction X and the third direction Z are perpendicular to each other.

[0083] As shown in Figure 5 , the body 1 is further provided with a solder pad 2, which is used for soldering and fixing with a solder strip, and the solder strip is used for realizing the electrical connection of adjacent battery pieces and outputting the current of the battery piece. The solder pad 2 is also used for electrical connection with the fine grid 4, and the current on the fine grid 4 can be transmitted to the solder strip through the solder pad 2, so as to realize the collection and transmission of the current on the battery piece.

[0084] As shown in Figure 5 , a plurality of solder pads 2 are arranged along the first direction Y, that is, one solder strip is soldered and fixed on the battery piece through a plurality of solder pads 2, so as to improve the pull force of the solder strip and the battery piece, reduce the risk that the separation of the solder strip and the battery piece leads to the reduction or even zero of the output power of the battery piece, and thus improve the performance of the battery piece.

[0085] When the battery piece is a battery piece without main grid, the solder pad 2 is arranged on the fine grid 4, that is, the fine grid 4 is directly electrically connected with the solder pad 2.

[0086] When the battery piece is a battery piece with main grid, the solder pad 2 is arranged on the main grid 5, and the fine grid 4 is electrically connected with the main grid 5, that is, the fine grid 4 is indirectly electrically connected with the solder pad 2 through the main grid 5.

[0087] In addition, when the battery piece is a battery piece with main grid, the solder pad 2 is arranged on the main grid 5, and the fine grid 4 can also be directly electrically connected with the solder pad 2.

[0088] The embodiments of the present application do not specially limit the specific type of the battery piece, and in order to facilitate description, the specific structure of the battery piece will be discussed in detail below taking the battery piece as an example.

[0089] As shown in Figure 5 , the body 1 further includes a first edge 11 and a second edge 12 distributed along the first direction Y.

[0090] As shown in Figure 5 , a plurality of solder pads 2 are arranged along the first direction Y, and the solder pad 2 located at the outermost side in the first direction Y is denoted as an edge solder pad 21, and the solder pad 2 between the two edge solder pads 21 is denoted as a middle solder pad 22, that is, in the first direction Y, the middle solder pad 22 is located on one side of the edge solder pad 21.

[0091] As shown in Figure 5 , at least one of the light-receiving surface and the back light-receiving surface is provided with a harpoon structure 3, and in the first direction Y, the harpoon structure 3 is located on the side of the edge solder pad 21 away from the middle solder pad 22.

[0092] Figure 6 is a structure enlarged view of part A in Figure 5 . As shown in Figure 6As shown, the harpoon structure 3 includes a first conduit portion 31 and a second conduit portion 32 . The first conduit portion 31 and the second conduit portion 32 are both connected to the edge pad 21 . A harpoon gap 33 is left between the first conduit portion 31 and the second conduit portion 32 in the second direction X.

[0093] The extension direction of the first confluence portion 31 may be parallel to the first direction Y, or may have an angle greater than 0 and less than 90° with the first direction Y. The embodiment of the present application does not specifically limit the extension direction of the first confluence portion 31.

[0094] The extension direction of the second confluence portion 32 may be parallel to the first direction Y, or may form an angle greater than 0 and less than 90° with the first direction Y. The embodiment of the present application does not specifically limit the extension direction of the second confluence portion 32 .

[0095] The first conduit portion 31 and the second conduit portion 32 may be symmetrically arranged on both sides of the edge pad 21 or asymmetrically arranged. The embodiment of the present application does not impose any special limitation on the distribution of the first conduit portion 31 and the second conduit portion 32 .

[0096] Take the side where the first edge 11 is located as an example, Figure 6 As shown, the fine grid 4 includes a first fine grid 41 and a second fine grid 42. In the first direction Y, the first fine grid 41 and the second fine grid 42 are both located on the side of the edge pad 21 away from the middle pad 22, and the first fine grid 41 is located between the second fine grid 42 and the edge pad 21.

[0097] like Figure 6 As shown, the first fine grid 41 is connected to the first confluence 31 and the second confluence 32 respectively, and the first fine grid 41 is disconnected at the harpoon gap 33 to form a first section 411 and a second section 412 arranged along the second direction X, the first section 411 is electrically connected to the first confluence 31, and the second section 412 is electrically connected to the second confluence 32.

[0098] like Figure 6 As shown, the second fine grid 42 is connected to the first confluence portion 31 and the second confluence portion 32 respectively, and the second fine grid 42 passes through the harpoon gap 33 along the second direction.

[0099] In this embodiment, the current on the first fine grid 41 and the second fine grid 42 can be transmitted to the edge pad 21 through the first busbar 31 and the second busbar 32, and then transmitted to the welding strip through the edge pad 21, so as to realize the collection and transmission of the current on the first fine grid 41 and the second fine grid 42, thereby improving the collection efficiency of the current at the edge of the battery cell, and thus improving the output power of the battery cell.

[0100] In this embodiment, the first fine grid 41 is disconnected at the harpoon structure 3 , which reduces the slurry required for the first fine grid 41 , thereby reducing the material cost of the first fine grid 41 , thereby facilitating reduction in the cost of the cell.

[0101] In this embodiment, the second fine grid 42 passes through the harpoon structure 3, that is, the second fine grid 42 is not disconnected at the harpoon structure 3, which optimizes the current collection path, helps reduce current transmission loss, and thus improves the output power of the battery cell.

[0102] The number of first fine grids 41 may be one or more, that is, the number of first fine grids 41 arranged in the first direction Y is N1, where 1≤N1≤10. The number of first fine grids 41 arranged here refers to the number of first fine grids 41 arranged on a single side of the cell. For example, on the side where the first edge of the cell is located, that is, between the edge pad 21 and the first edge 11, there are one or more first fine grids 41.

[0103] For example, between the edge pad 21 and the first edge 11 , the number of the first fine grids 41 arranged in the first direction Y may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and so on.

[0104] When there are multiple first fine gates 41 , the multiple first fine gates 41 are all located on the side of the second fine gate 42 facing the edge pad 21 .

[0105] The number of the second fine grids 42 can be one or more. The number of the second fine grids 42 arranged here refers to the number of the second fine grids 42 arranged on a single side of the battery cell. For example, on the side where the first edge of the battery cell is located, that is, between the edge pad 21 and the first edge 11, the number of the second fine grids 42 is one or more.

[0106] When there are multiple second fine gates 42 , the multiple second fine gates 42 are all located on a side of the first fine gate 41 away from the edge pad 21 .

[0107] In some embodiments, as Figure 6 As shown, taking the first edge 11 as an example, the fine grid 4 between the edge pad 21 and the first edge 11, which is closest to the first edge 11, is constructed as a second fine grid 42 that penetrates the harpoon structure 3, and the fine grid 4 located on the outermost side in the first direction Y is recorded as an edge fine grid, and the second fine grid 42 is constructed as an edge fine grid.

[0108] In this embodiment, the second fine grid 42 is located at the outermost side, which improves the current collection efficiency at the edge of the cell, thereby improving the brightness uniformity of the cell EL test, reducing the risk of local failure of the cell after aging, and further helping to improve the output power of the cell.

[0109] Figure 7 for Figure 5 A structural enlargement diagram of part A in other embodiments. In other embodiments, as Figure 7 As shown, the fine gate 4 further includes a third fine gate 43 . In the first direction Y, the third fine gate 43 is located on a side of the second fine gate 42 away from the first fine gate 41 .

[0110] The third fine grid 43 is connected to the first confluence 31 and the second confluence 32 respectively. The third fine grid 43 is disconnected at the harpoon gap 33 to form a third section 431 and a fourth section 432 distributed along the second direction X. The third section 431 is electrically connected to the first confluence 31, and the fourth section 432 is electrically connected to the second confluence 32.

[0111] Taking the first edge 11 as an example, Figure 7 As shown, the fine grid 4 closest to the first edge 11 is configured as an interrupted third fine grid 43 , and the fine grid 4 located outermost in the first direction Y is recorded as an edge fine grid, and the third fine grid 43 is configured as an edge fine grid.

[0112] In this embodiment, the third fine grid 43 is disconnected at the harpoon structure 3 , which reduces the slurry required for the third fine grid 43 , thereby reducing the material cost of the third fine grid 43 , thereby helping to reduce the cost of the battery cell.

[0113] In this embodiment, the edge fine grid is disconnected at the harpoon structure 3, which can optimize the current collection path at the edge of the battery cell and reduce the current transmission loss, thereby facilitating the improvement of the output power of the battery cell.

[0114] The number of the third fine grids 43 may be one or more, that is, the number of the third fine grids 43 arranged in the first direction Y is N2, where 1≤N2≤10. The number of the third fine grids 43 arranged here refers to the number of the third fine grids 43 arranged on a single side of the cell. For example, on the side where the first edge of the cell is located, that is, between the edge pad 21 and the first edge 11, there are one or more third fine grids 43.

[0115] For example, between the edge pad 21 and the first edge 11 , the number of the third fine grids 43 arranged in the first direction Y may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and so on.

[0116] When there are multiple third fine gates 43 , the multiple third fine gates 43 are all located on a side of the second fine gate 42 away from the edge pad 21 .

[0117] In some embodiments, as Figure 7As shown, one end of the first segment 411 toward the second segment 412 is connected to the first confluence portion 31 , and one end of the second segment 412 toward the first segment 411 is connected to the second confluence portion 32 , so as to reduce the length of the first fine grid 41 and thus reduce the material cost of the first fine grid 41 .

[0118] Figure 8 for Figure 5 A part of the structure of some embodiments of the invention is enlarged. In other embodiments, as Figure 8 As shown, the first section 411 is connected to the first conduit 31 and extends into the harpoon gap 33 along the second direction X, and the second section 412 is connected to the second conduit 32 and extends into the harpoon gap 33 along the second direction X, so as to increase the length of the first fine grid 41 and improve the current collection efficiency of the first fine grid 41.

[0119] In some embodiments, as Figure 7 As shown, one end of the third segment 431 toward the fourth segment 432 is connected to the first confluence portion 31 , and one end of the fourth segment 432 toward the third segment 431 is connected to the second confluence portion 32 , so as to reduce the length of the third fine grid 43 and thus reduce the material cost of the third fine grid 43 .

[0120] In other embodiments, Figure 8 As shown, the third section 431 is connected to the first conduit 31 and extends into the harpoon gap 33 along the second direction X. The fourth section 432 is connected to the second conduit 32 and extends into the harpoon gap 33 along the second direction X to increase the length of the third fine grid 43 and improve the current collection efficiency of the third fine grid 43.

[0121] The structure of the fine gate 4 at the first edge 11 and the structure of the fine gate 4 at the second edge 12 may be the same or different.

[0122] Figure 9 for Figure 5 Schematic diagram of the partial structure of the battery cell in some embodiments. Figure 9 As shown, the edge pad 21 includes a first edge pad 211 and a second edge pad 212 arranged along a first direction Y. In the first direction Y, the first edge pad 211 is located between the first edge 11 and the second edge pad 212 .

[0123] In the first direction Y, a harpoon structure 3 is provided between the first edge pad 211 and the first edge 11 , and between the second edge pad 212 and the second edge 12 .

[0124] When the structure of the fine gate 4 at the first edge 11 is the same as that of the fine gate 4 at the second edge 12, the above-mentioned first fine gate 41 and second fine gate 42 are arranged between the first edge pad 211 and the first edge 11, and the above-mentioned first fine gate 41 and second fine gate 42 are arranged between the second edge pad 212 and the second edge 12.

[0125] Alternatively, when the structure of the fine gate 4 at the first edge 11 is the same as that of the fine gate 4 at the second edge 12, as shown in FIG. Figure 9 As shown, the first fine gate 41 , the second fine gate 42 and the third fine gate 43 are arranged between the first edge pad 211 and the first edge 11 , and the first fine gate 41 , the second fine gate 42 and the third fine gate 43 are arranged between the second edge pad 212 and the second edge 12 .

[0126] When the structure of the fine gate 4 at the first edge 11 is different from that at the second edge 12, the structure of the fine gate 4 at the first edge 11 may be as follows: Figures 6 to 8 As shown, the first fine gate 41 and the second fine gate 42 are provided between the first edge pad 211 and the first edge 11 , or the first fine gate 41 , the second fine gate 42 and the third fine gate 43 are provided between the first edge pad 211 and the first edge 11 .

[0127] When the structure of the fine gate 4 at the first edge 11 is different from that at the second edge 12 , several possible designs of the structure of the fine gate 4 at the second edge 12 are discussed in detail below.

[0128] Figure 10 for Figure 5 An enlarged view of part B in some embodiments. Figure 10 As shown, the fine grid 4 also includes a fourth fine grid 44. In the first direction Y, the fourth fine grid 44 is located between the second edge pad 212 and the second edge 12. The fourth fine grid 44 is respectively connected to the first bus 31 and the second bus 32, and the fourth fine grid 44 passes through the harpoon gap 33 along the second direction.

[0129] In this embodiment, the fourth fine grid 44 passes through the harpoon structure 3, that is, the fourth fine grid 44 is not disconnected at the harpoon structure 3, which optimizes the current collection path, helps reduce current transmission loss, and thus improves the output power of the battery cell.

[0130] In some embodiments, as Figure 10 As shown, the outermost fine grid 4 in the first direction Y is marked as an edge fine grid, and the fourth fine grid 44 is configured as an edge fine grid.

[0131] In this embodiment, the fourth fine grid 44 is located at the outermost side, which improves the current collection efficiency at the second edge 12 of the cell, thereby helping to improve the brightness uniformity of the cell EL test, reducing the risk of local failure of the cell after aging, and further helping to improve the output power of the cell.

[0132] Figure 11 for Figure 5 FIG. 1 is an enlarged view of part B in some other embodiments. Figure 11 As shown, the fine grid 4 further includes a fifth fine grid 45. In the first direction Y, the fifth fine grid 45 is located between the fourth fine grid 44 and the second edge 12. The fifth fine grid 45 is connected to the first confluence portion 31 and the second confluence portion 32 respectively. The fifth fine grid 45 is disconnected at the harpoon gap 33 to form a fifth segment 451 and a sixth segment 452 arranged along the second direction X.

[0133] The outermost fine grid 4 in the first direction Y is referred to as an edge fine grid, and the fifth fine grid 45 is configured as an edge fine grid.

[0134] In this embodiment, the fifth fine grid 45 is disconnected at the harpoon structure 3 , which reduces the slurry required for the fifth fine grid 45 , thereby reducing the material cost of the fifth fine grid 45 , thereby helping to reduce the cost of the battery cell.

[0135] In this embodiment, the edge fine grid is disconnected at the harpoon structure 3, which can optimize the current collection path at the edge of the battery cell and reduce the current transmission loss, thereby facilitating the improvement of the output power of the battery cell.

[0136] The number of the fifth fine grids 45 may be one or more, that is, the number of the fifth fine grids 45 arranged in the first direction Y is N3, where 1≤N3≤10. The number of the fifth fine grids 45 arranged here refers to the number of the fifth fine grids 45 arranged on a single side of the cell. For example, on the side where the first edge of the cell is located, that is, between the second edge pad 212 and the second edge 12, there are one or more fifth fine grids 45.

[0137] For example, between the second edge pad 212 and the second edge 12 , the number of fifth fine grids 45 arranged in the first direction Y may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc.

[0138] When there are multiple fifth fine gates 45 , the multiple fifth fine gates 45 are all located on a side of the fourth fine gate 44 away from the second edge pad 212 .

[0139] The number of the fourth fine gate 44 may be one or more. When there are more than one fourth fine gate 44 , the plurality of fourth fine gates 44 are all located on the side of the fifth fine gate 45 facing the second edge pad 212 .

[0140] In some embodiments, as Figure 11 As shown, one end of the fifth segment 451 toward the sixth segment 452 is connected to the first confluence portion 31 , and one end of the sixth segment 452 toward the fifth segment 451 is connected to the second confluence portion 32 , so as to reduce the length of the first fine grid 41 and thus reduce the material cost of the first fine grid 41 .

[0141] In other embodiments, the fifth segment 451 is connected to the first conduit 31 and extends into the harpoon gap 33 along the second direction X, and the sixth segment 452 is connected to the second conduit 32 and extends into the harpoon gap 33 along the second direction X, so as to increase the length of the fifth fine grid 45 and improve the current collection efficiency of the fifth fine grid 45.

[0142] Based on the above-described structure of the fine grid 4, on the light-facing side of the body 1, the structure of the fine grid 4 at the first edge 11 can be the same as or different from the structure of the fine grid 4 at the second edge 12. On the backlight side of the body 1, the structure of the fine grid 4 at the first edge 11 can be the same as or different from the structure of the fine grid 4 at the second edge 12. The structure of the fine grid 4 on the light-facing side of the body 1 can be the same as or different from the structure of the fine grid 4 on the backlight side.

[0143] Figure 12 This is a schematic diagram of the partial structure of the light-facing surface of the battery cell provided in this application in some embodiments. Figure 12 The example shows that on the light-facing surface of the main body 1, the structure of the fine grid 4 at the first edge 11 is the same as the structure of the fine grid 4 at the second edge 12, and a harpoon structure 3, a disconnected first fine grid 41 and a penetrating second fine grid 42 are arranged between the first edge pad 211 and the first edge 11, and a harpoon structure 3, a disconnected first fine grid 41 and a penetrating second fine grid 42 are arranged between the second edge pad 212 and the second edge 12.

[0144] Figure 13 Schematic diagram of the partial structure of the light-facing surface of the battery cell provided in this application in other embodiments. Figure 13 The example shows that on the light-facing surface of the main body 1, the structure of the fine grid 4 at the first edge 11 is different from the structure of the fine grid 4 at the second edge 12, and a harpoon structure 3, a disconnected first fine grid 41 and a penetrating second fine grid 42 are arranged between the first edge pad 211 and the first edge 11, and the second fine grid 42 is constructed as the edge fine grid 46 at the first edge 11, and a harpoon structure 3, a penetrating fourth fine grid 44 and a disconnected fifth fine grid 45 are arranged between the second edge pad 212 and the second edge 12, and the fifth fine grid 45 is constructed as the edge fine grid 46 at the second edge 12.

[0145] Figure 14 The backlight surface of the cell provided in this application is a partial structural diagram in some embodiments. Figure 12 and Figure 14 , or, refer to Figure 13 and Figure 14 , Figure 14 The structure of the fine grid 4 on the light-facing side of the main body 1 is different from that on the backlight side. Figure 14 The example shows that on the backlight surface of the main body 1, the structure of the fine grid 4 at the first edge 11 is different from the structure of the fine grid 4 at the second edge 12, and a harpoon structure 3, a disconnected first fine grid 41, a penetrating second fine grid 42 and a disconnected third fine grid 43 are arranged between the first edge pad 211 and the first edge 11. The third fine grid 43 is constructed as the edge fine grid 46 at the first edge 11. A harpoon structure 3 and a penetrating fourth fine grid 44 are arranged between the second edge pad 212 and the second edge 12. The fourth fine grid 44 is constructed as the edge fine grid 46 at the second edge 12.

[0146] Based on the above-mentioned battery cell, the pulling force between the soldering ribbon and the battery cell can also be improved by adjusting the structure and arrangement of the soldering pad 2. The structural design of the soldering pad 2 is discussed in detail below.

[0147] Figure 15 for Figure 5 An enlarged view of part C in some embodiments. Figure 15 As shown, the pad 2 located on the outermost side in the first direction Y is recorded as an edge pad 21 , and the pad 2 between the two edge pads 21 is recorded as a middle pad 22 .

[0148] like Figure 15 As shown, the middle pad 22 includes a main pad 221 and an auxiliary pad 222. In the third direction Z, the projected area of ​​the main pad 221 is larger than the projected area of ​​the auxiliary pad 222. Multiple main pads 221 are arranged along the first direction Y, and at least two auxiliary pads 222 are included between two adjacent main pads 221.

[0149] In this embodiment, the area of ​​the main soldering pad 221 is larger than the area of ​​the auxiliary soldering pad 222, so that the welding area between the main soldering pad 221 and the soldering ribbon is larger than the welding area between the auxiliary soldering pad 222 and the soldering ribbon, thereby increasing the pulling force between the soldering ribbon and the battery cell, reducing the risk of the soldering ribbon detaching from the battery cell, and improving the anti-aging ability of the battery cell and the performance of the battery cell.

[0150] The welding area between the main pad 221 and the welding ribbon is large, which can improve the current transmission capacity between the main pad 221 and the welding ribbon, and further improve the current collection capacity of the welding ribbon, so as to increase the output power of the battery cell.

[0151] A larger main pad 221 and a smaller auxiliary pad 222 are provided at the same time. While increasing the pulling force between the soldering ribbon and the battery cell and improving the current transmission capability, the slurry required for the pad 2 can be reduced, thereby reducing the cost of the pad 2 and the battery cell.

[0152] The width of the main pad 221 in the second direction X is W1, and the width of the sub pad 222 in the second direction X is W2, W2 < W1.

[0153] In the embodiment, W2 < W1 is met on the premise that the area of the main pad 221 is greater than the area of the sub pad 222, so that the distance of the fine grids connected with the main pad 221 and the fine grids connected with the sub pad 222 in the first direction Y is reduced, which is beneficial to increase the number of the fine grids arranged in the first direction Y and improve the output power of the battery piece.

[0154] 1mm ≤ W1 ≤ 3.5mm, for example, the width of the main pad 221 in the second direction X can be 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, etc.

[0155] If the width of the main pad 221 in the second direction X is small, and the distance of the fine grids connected with the main pad 221 and the fine grids connected with the sub pad 222 in the first direction Y is a preset value, that is, the size of the main pad 221 in the first direction Y is a preset value, then the welding area of the main pad 221 and the solder strip is small, and the pulling force of the solder strip and the battery piece is small.

[0156] If the width of the main pad 221 in the second direction X is small, and the area of the main pad 221 is a preset value, then the size of the main pad 221 in the first direction Y is large, and when the distance of the main pad 221 and the sub pad 222 in the first direction Y is a preset value, the distance of the fine grids connected with the main pad 221 and the fine grids connected with the sub pad 222 in the first direction Y is large, and the number of the fine grids arranged in the first direction Y is small, which affects the output power of the battery piece.

[0157] If the width of the main pad 221 in the second direction X is large, and the width of the solder strip in the second direction X is a preset value, and the area of the main pad 221 is a preset value, then the size of the main pad 221 in the first direction Y is small, so that the welding area of the main pad 221 and the sub pad 222 and the solder strip is small, and the pulling force of the solder strip and the battery piece is small.

[0158] If the width of the main pad 221 in the second direction X is large, and the contact area of the main pad 221 and the solder strip is a preset value, then the area of the main pad 221 is large, so that the material cost of the main pad 221 is high.

[0159] Therefore, 1mm≤W1≤3.5mm can increase the welding area between the main pad 221 and the welding ribbon to increase the pulling force of the welding ribbon on the battery cell, reduce the material cost of the main pad 221, and increase the number of fine grids to increase the output power of the battery cell.

[0160] Exemplarily, 1mm≤W1≤1.5mm, the width of the main pad 221 in the second direction X can be 1mm, 1.01mm, 1.03mm, 1.05mm, 1.07mm, 1.09mm, 1.1mm, 1.11mm, 1.13mm, 1.15mm, 1.17mm, 1.19mm, 1.2mm, 1.21mm, 1.23mm, 1.25mm, 1.27mm, 1.29mm, 1.3mm, 1.31mm, 1.33mm, 1.35mm, 1.37mm, 1.39mm, 1.4mm, 1.41mm, 1.43mm, 1.45mm, 1.47mm, 1.49mm, 1.5mm, etc.

[0161] Exemplarily, 1.5mm≤W1≤2mm, the width of the main pad 221 in the second direction X can be 1.5mm, 1.51mm, 1.53mm, 1.55mm, 1.57mm, 1.59mm, 1.6mm, 1.61mm, 1.63mm, 1.65mm, 1.67mm, 1.69mm, 1.7mm, 1.71mm, 1.73mm, 1.75mm, 1.77mm, 1.79mm, 1.8mm, 1.81mm, 1.83mm, 1.85mm, 1.87mm, 1.89mm, 1.9mm, 1.91mm, 1.93mm, 1.95mm, 1.97mm, 1.99mm, 2mm, etc.

[0162] Exemplarily, 2mm≤W1≤2.5mm, the width of the main pad 221 in the second direction X can be 2mm, 2.01mm, 2.03mm, 2.05mm, 2.07mm, 2.09mm, 2.1mm, 2.11mm, 2.13mm, 2.15mm, 2.17mm, 2.19mm, 2.2mm, 2.21mm, 2.23mm, 2.25mm, 2.27mm, 2.29mm, 2.3mm, 2.31mm, 2.33mm, 2.35mm, 2.37mm, 2.39mm, 2.4mm, 2.41mm, 2.43mm, 2.45mm, 2.47mm, 2.49mm, 2.5mm, etc.

[0163] Exemplarily, 2.5mm≤W1≤3mm, the width of the main pad 221 in the second direction X can be 2.5mm, 2.51mm, 2.53mm, 2.55mm, 2.57mm, 2.59mm, 2.6mm, 2.61mm, 2.63mm, 2.65mm, 2.67mm, 2.69mm, 2.7mm, 2.71mm, 2.73mm, 2.75mm, 2.77mm, 2.79mm, 2.8mm, 2.81mm, 2.83mm, 2.85mm, 2.87mm, 2.89mm, 2.9mm, 2.91mm, 2.93mm, 2.95mm, 2.97mm, 2.99mm, 3mm, etc.

[0164] Exemplarily, 3mm≤W1≤3.5mm, the width of the main pad 221 in the second direction X can be 3mm, 3.01mm, 3.03mm, 3.05mm, 3.07mm, 3.09mm, 3.1mm, 3.11mm, 3.13mm, 3.15mm, 3.17mm, 3.19mm, 3.2mm, 3.21mm, 3.23mm, 3.25mm, 3.27mm, 3.29mm, 3.3mm, 3.31mm, 3.33mm, 3.35mm, 3.37mm, 3.39mm, 3.4mm, 3.41mm, 3.43mm, 3.45mm, 3.47mm, 3.49mm, 3.5mm, etc.

[0165] 0.3 mm≤W2≤1.2 mm. For example, the width of the auxiliary pad 222 in the second direction X may be 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, etc.

[0166] If the width of the auxiliary pad 222 in the second direction X is small, and the distance between the fine grid connected to the main pad 221 and the fine grid connected to the auxiliary pad 222 in the first direction Y is a preset value, that is, when the size of the auxiliary pad 222 in the first direction Y is a preset value, then the welding area between the auxiliary pad 222 and the welding ribbon is small, and the pulling force between the welding ribbon and the battery cell is small.

[0167] If the width of the auxiliary pad 222 in the second direction X is small and the area of ​​the auxiliary pad 222 is a preset value, the size of the auxiliary pad 222 in the first direction Y is large. When the distance between the auxiliary pad 222 and the main pad 221 in the first direction Y is a preset value, the distance between the fine grid connected to the main pad 221 and the fine grid connected to the auxiliary pad 222 in the first direction Y is large, and the number of fine grids set in the first direction Y is small, which affects the output power of the battery cell.

[0168] If the width of the auxiliary solder pad 222 in the second direction X is large, the width of the solder strip in the second direction X is a preset value, and the area of the auxiliary solder pad 222 is a preset value, the size of the auxiliary solder pad 222 in the first direction Y is small, so that the welding area of the main solder pad 221 and the auxiliary solder pad 222 with the solder strip is small, and the pulling force of the solder strip on the battery piece is small.

[0169] If the width of the auxiliary solder pad 222 in the second direction X is large, and the contact area of the auxiliary solder pad 222 with the solder strip is a preset value, the area of the auxiliary solder pad 222 is large, so that the material cost of the auxiliary solder pad 222 is high.

[0170] Therefore, 0.3mm≤W2≤1.2mm can improve the welding area of the auxiliary solder pad 222 with the solder strip, improve the pulling force of the solder strip on the battery piece, reduce the material cost of the auxiliary solder pad 222, and increase the number of thin grids to improve the output power of the battery piece.

[0171] For example, 0.3mm≤W2≤0.6mm, the width of the auxiliary solder pad 222 in the second direction X can be 0.3mm, 0.31mm, 0.33mm, 0.35mm, 0.37mm, 0.39mm, 0.4mm, 0.41mm, 0.43mm, 0.45mm, 0.47mm, 0.49mm, 0.5mm, 0.51mm, 0.53mm, 0.55mm, 0.57mm, 0.59mm, 0.6mm, etc.

[0172] For example, 0.6mm≤W2≤0.9mm, the width of the auxiliary solder pad 222 in the second direction X can be 0.6mm, 0.61mm, 0.63mm, 0.65mm, 0.67mm, 0.69mm, 0.7mm, 0.71mm, 0.73mm, 0.75mm, 0.77mm, 0.79mm, 0.8mm, 0.81mm, 0.83mm, 0.85mm, 0.87mm, 0.89mm, 0.9mm, etc.

[0173] For example, 0.9mm≤W2≤1.2mm, the width of the auxiliary solder pad 222 in the second direction X can be 0.9mm, 0.91mm, 0.93mm, 0.95mm, 0.97mm, 0.99mm, 1mm, 1.01mm, 1.03mm, 1.05mm, 1.07mm, 1.09mm, 1.1mm, 1.11mm, 1.13mm, 1.15mm, 1.17mm, 1.19mm, 1.2mm, etc.

[0174] In some embodiments, in the third direction Z, the projection area of the edge solder pad 21 is equal to the projection area of the main solder pad 221.

[0175] In other implementations, in the third direction Z, the projected area of ​​the edge pad 21 is larger than the projected area of ​​the main pad 221, so as to improve the welding strength between the edge of the battery cell and the welding ribbon, thereby increasing the pulling force of the welding ribbon at the edge of the battery cell, reducing the risk of the welding ribbon detaching from the battery cell, and improving the anti-aging ability of the battery cell and the performance of the battery cell.

[0176] like Figure 15 As shown, in the first direction Y, at least three auxiliary pads 222 are included between the edge pad 21 and the main pad 221 adjacent to it, so as to increase the pulling force of the solder ribbon at the edge of the battery cell, reduce the risk of the solder ribbon detaching from the battery cell, and improve the anti-aging ability of the battery cell and the performance of the battery cell.

[0177] At least three auxiliary pads 222 are included between the edge pad 21 and the adjacent main pad 221, which can reduce the material cost of the pad 2 while meeting the pulling force of the solder strip at the edge of the battery cell, thereby reducing the cost of the battery cell.

[0178] The outline shape of the pad 2 includes but is not limited to a circle, a triangle, a quadrilateral, a rectangle, a T-shape, an I-shape, a Z-shape, etc. The embodiment of the present application does not specifically limit the shape of the pad 2.

[0179] Figure 16 for Figure 5 In some embodiments, the outline of the main pad 221 is circular or rectangular, and the outline of the auxiliary pad 222 is T-shaped, I-shaped, or Z-shaped.

[0180] In this embodiment, the outline of the main pad 221 is circular or rectangular, so as to increase the area of ​​the main pad 221 and improve the current transmission efficiency and pulling force between the main pad 221 and the soldering ribbon.

[0181] The contour shape of the auxiliary pad 222 is T-shaped, I-shaped or Z-shaped. Under the premise that the area of ​​the auxiliary pad 222 is small, it can increase and improve the welding stress between the auxiliary pad 222 and the welding strip, reduce local stress concentration, and reduce the risk of damage caused by fatigue or repeated loads, so as to enhance the anti-aging ability of the battery cell.

[0182] In some embodiments, as Figure 16 As shown, the number of pads 2 and fine grids 4 in the first direction Y is the same, that is, the number of fine grids 4 between two adjacent pads 2 is 0, so that each fine grid 4 is electrically connected to the welding strip through the pad 2, which increases the number of pads 2, improves the pulling force between the pad 2 and the battery cell, and also improves the current collection efficiency of the welding strip on the battery cell, thereby improving the output power of the battery cell.

[0183] Figure 17 for Figure 5 In some embodiments, the enlarged view of the D part is shown. In other embodiments, Figure 17 As shown, in the first direction Y, at least one fine grid 4 is included between two adjacent pads 2 to reduce the number of pads 2, thereby reducing the material cost of the pads 2 and reducing the cost of the battery cell.

[0184] Among them, such as Figure 17 As shown, the pads 2 and the fine grids 4 can be periodically arranged in the first direction Y to improve the stress distribution between the soldering strips and the cells and reduce the risk of damage to the cells or soldering strips due to stress concentration.

[0185] Figure 18 for Figure 5 When the number of the fine grids 4 between two adjacent pads 2 is 0, as shown in FIG. Figure 18 As shown, the fine gate 4 includes a main fine gate 48 and a secondary fine gate 49. The end of the main fine gate 48 contacts the main pad 221, and the end of the secondary fine gate 49 contacts the secondary pad 222. In the first direction Y, the distance between the main fine gate 48 and the adjacent secondary fine gate 49 is L1, and the distance between two adjacent secondary fine gates 49 is L2. 0.3≤L1 / L2≤7. For example, the ratio of L1 to L2 can be 0.3, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, etc.

[0186] Illustratively, 0.3≤L1 / L2≤1, and the ratio of L1 to L2 can be 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, etc.

[0187] Illustratively, 1≤L1 / L2≤3, and the ratio of L1 to L2 can be 1, 1.1, 1.3, 1.5, 1.7, 1.9, 2, 2.1, 2.2, 2.3, 2.5, 2.7, 2.9, 3, etc.

[0188] Illustratively, 3≤L1 / L2≤5, and the ratio of L1 to L2 can be 3, 3.1, 3.3, 3.5, 3.7, 3.9, 4, 4.1, 4.2, 4.3, 4.5, 4.7, 4.9, 5, etc.

[0189] Illustratively, 5≤L1 / L2≤7, and the ratio of L1 to L2 can be 5, 5.1, 5.3, 5.5, 5.7, 5.9, 6, 6.1, 6.2, 6.3, 6.5, 6.7, 6.9, 7, etc.

[0190] And L2<L1.

[0191] In this embodiment, the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 is large, and the distance between two adjacent auxiliary fine grids 49 is small. This increases the spacing between the main solder pad 221 and the adjacent auxiliary solder pad 222, and reduces the spacing between adjacent auxiliary solder pads 222. This reduces the risk of contact between the main solder pad 221 and the adjacent auxiliary solder pad 222, thereby reducing the risk of reduced efficiency of the solar cell due to a large surface obstruction area, thereby facilitating improved output power of the solar cell. At the same time, the smaller spacing between adjacent auxiliary solder pads 222 facilitates increasing the number of auxiliary solder pads 222, thereby facilitating increased pullout strength between the solder ribbon and the solar cell, thereby improving the anti-aging performance of the solar cell.

[0192] 0.5mm≤L1≤2mm, the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, etc.

[0193] If the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 is small, the risk of the main pad 221 and the adjacent auxiliary pad 222 contacting each other is greater, and the risk of increasing the shielding area of ​​the battery cell is higher, affecting the output power of the battery cell.

[0194] If the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 is small, the number of fine grids 4 is large, resulting in a higher cost for the solar cell.

[0195] If the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 is large, the number of distributed solder pads 2 is small, which affects the pulling force between the solder ribbon and the solar cell, thereby improving the anti-aging performance of the solar cell.

[0196] If the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 is large, the number of fine grids 4 is small, resulting in a low current collection efficiency of the cell, which affects the output power of the cell.

[0197] Therefore, 0.5mm≤L1≤2mm can reduce the area of ​​the battery cell blocked by the pad 2, thereby increasing the output power of the battery cell. At the same time, the number of pads 2 can be increased to increase the pulling force between the solder ribbon and the battery cell, thereby improving the anti-aging performance of the battery cell. At the same time, it can reduce the material cost of the battery cell while increasing the output power of the battery cell.

[0198] Exemplarily, 0.5mm≤L1≤0.7mm, and the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 can be 0.5mm, 0.51mm, 0.52mm, 0.53mm, 0.54mm, 0.55mm, 0.56mm, 0.57mm, 0.58mm, 0.59mm, 0.6mm, 0.61mm, 0.62mm, 0.63mm, 0.64mm, 0.65mm, 0.66mm, 0.67mm, 0.68mm, 0.69mm, 0.7mm, etc.

[0199] Exemplarily, 0.7mm≤L1≤0.9mm, and the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 can be 0.7mm, 0.71mm, 0.72mm, 0.73mm, 0.74mm, 0.75mm, 0.76mm, 0.77mm, 0.78mm, 0.79mm, 0.8mm, 0.81mm, 0.82mm, 0.83mm, 0.84mm, 0.85mm, 0.86mm, 0.87mm, 0.88mm, 0.89mm, 0.9mm, etc.

[0200] Exemplarily, 0.9mm≤L1≤1.1mm, and the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 can be 0.9mm, 0.91mm, 0.92mm, 0.93mm, 0.94mm, 0.95mm, 0.96mm, 0.97mm, 0.98mm, 0.99mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 1.1mm, etc.

[0201] Exemplarily, 1.1mm≤L1≤1.3mm, and the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 can be 1.1mm, 1.11mm, 1.12mm, 1.13mm, 1.14mm, 1.15mm, 1.16mm, 1.17mm, 1.18mm, 1.19mm, 1.2mm, 1.21mm, 1.22mm, 1.23mm, 1.24mm, 1.25mm, 1.26mm, 1.27mm, 1.28mm, 1.29mm, 1.3mm, etc.

[0202] Exemplarily, 1.3mm≤L1≤1.5mm, and the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 can be 1.3mm, 1.31mm, 1.32mm, 1.33mm, 1.34mm, 1.35mm, 1.36mm, 1.37mm, 1.38mm, 1.39mm, 1.4mm, 1.41mm, 1.42mm, 1.43mm, 1.44mm, 1.45mm, 1.46mm, 1.47mm, 1.48mm, 1.49mm, 1.5mm, etc.

[0203] Exemplarily, 1.5mm≤L1≤1.7mm, and the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 can be 1.5mm, 1.51mm, 1.52mm, 1.53mm, 1.54mm, 1.55mm, 1.56mm, 1.57mm, 1.58mm, 1.59mm, 1.6mm, 1.61mm, 1.62mm, 1.63mm, 1.64mm, 1.65mm, 1.66mm, 1.67mm, 1.68mm, 1.69mm, 1.7mm, etc.

[0204] Exemplarily, 1.7mm≤L1≤1.9mm, and the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 can be 1.7mm, 1.71mm, 1.72mm, 1.73mm, 1.74mm, 1.75mm, 1.76mm, 1.77mm, 1.78mm, 1.79mm, 1.8mm, 1.81mm, 1.82mm, 1.83mm, 1.84mm, 1.85mm, 1.86mm, 1.87mm, 1.88mm, 1.89mm, 1.9mm, etc.

[0205] Exemplarily, 1.9mm≤L1≤2mm, and the distance between the main fine grid 48 and the adjacent auxiliary fine grid 49 can be 1.9mm, 1.905mm, 1.91mm, 1.915mm, 1.92mm, 1.925mm, 1.93mm, 1.935mm, 1.94mm, 1.945mm, 1.95mm, 1.955mm, 1.96mm, 1.965mm, 1.97mm, 1.975mm, 1.98mm, 1.985mm, 1.99mm, 1.995mm, 2mm, etc.

[0206] 0.3mm≤L2≤1.5mm, and the distance between two adjacent auxiliary fine grids 49 can be 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, etc.

[0207] If the distance between two adjacent auxiliary fine grids 49 is small, the risk of two adjacent auxiliary pads 222 contacting each other is greater, and the risk of increasing the shielding area of ​​the solar cell is higher, thereby affecting the output power of the solar cell.

[0208] If the distance between two adjacent auxiliary fine grids 49 is small, the number of fine grids 4 is large, resulting in a higher cost for the solar cell.

[0209] If the distance between two adjacent auxiliary fine grids 49 is large, the number of distributed solder pads 2 is small, which affects the pulling force between the solder ribbon and the solar cell, thereby improving the anti-aging performance of the solar cell.

[0210] If the distance between two adjacent auxiliary fine grids 49 is large, the number of fine grids 4 is small, resulting in a low current collection efficiency of the cell, which affects the output power of the cell.

[0211] Therefore, 0.3mm≤L2≤1.5mm can reduce the area of ​​the battery cell blocked by the pad 2, thereby increasing the output power of the battery cell. At the same time, the number of pads 2 can be increased to increase the pulling force between the solder ribbon and the battery cell, thereby improving the anti-aging performance of the battery cell. At the same time, it can reduce the material cost of the battery cell while increasing the output power of the battery cell.

[0212] Exemplarily, 0.3mm≤L2≤0.5mm, and the distance between two adjacent secondary fine grids 49 can be 0.3mm, 0.31mm, 0.32mm, 0.33mm, 0.34mm, 0.35mm, 0.36mm, 0.37mm, 0.38mm, 0.39mm, 0.4mm, 0.41mm, 0.42mm, 0.43mm, 0.44mm, 0.45mm, 0.46mm, 0.47mm, 0.48mm, 0.49mm, 0.5mm, etc.

[0213] Exemplarily, 0.5mm≤L2≤0.7mm, and the distance between two adjacent secondary fine grids 49 can be 0.5mm, 0.51mm, 0.52mm, 0.53mm, 0.54mm, 0.55mm, 0.56mm, 0.57mm, 0.58mm, 0.59mm, 0.6mm, 0.61mm, 0.62mm, 0.63mm, 0.64mm, 0.65mm, 0.66mm, 0.67mm, 0.68mm, 0.69mm, 0.7mm, etc.

[0214] Exemplarily, 0.7mm≤L2≤0.9mm, and the distance between two adjacent secondary fine grids 49 can be 0.7mm, 0.71mm, 0.72mm, 0.73mm, 0.74mm, 0.75mm, 0.76mm, 0.77mm, 0.78mm, 0.79mm, 0.8mm, 0.81mm, 0.82mm, 0.83mm, 0.84mm, 0.85mm, 0.86mm, 0.87mm, 0.88mm, 0.89mm, 0.9mm, etc.

[0215] Exemplarily, 0.9mm≤L2≤1.1mm, and the distance between two adjacent secondary fine grids 49 can be 0.9mm, 0.91mm, 0.92mm, 0.93mm, 0.94mm, 0.95mm, 0.96mm, 0.97mm, 0.98mm, 0.99mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 1.1mm, etc.

[0216] Exemplarily, 1.1mm≤L2≤1.3mm, and the distance between two adjacent secondary fine grids 49 can be 1.1mm, 1.11mm, 1.12mm, 1.13mm, 1.14mm, 1.15mm, 1.16mm, 1.17mm, 1.18mm, 1.19mm, 1.2mm, 1.21mm, 1.22mm, 1.23mm, 1.24mm, 1.25mm, 1.26mm, 1.27mm, 1.28mm, 1.29mm, 1.3mm, etc.

[0217] Exemplarily, 1.3mm≤L2≤1.5mm, and the distance between two adjacent secondary fine grids 49 can be 1.3mm, 1.31mm, 1.32mm, 1.33mm, 1.34mm, 1.35mm, 1.36mm, 1.37mm, 1.38mm, 1.39mm, 1.4mm, 1.41mm, 1.42mm, 1.43mm, 1.44mm, 1.45mm, 1.46mm, 1.47mm, 1.48mm, 1.49mm, 1.5mm, etc.

[0218] The battery cell can be a busbarless battery cell or a busbar battery cell.

[0219] When the battery cell is a busbar-less battery cell, Figure 18 Taking the structure shown as an example, the pad 2 is directly connected to the fine grid 4 to reduce the paste cost of the cell and reduce the obstruction of the cell surface, which is beneficial to improving the output power of the cell.

[0220] Figure 19is a schematic diagram of the local structure of a battery cell in some embodiments, Figure 20 for Figure 19 The structure of part E in the figure is enlarged. When the cell is a busbar cell, such as Figure 19 and Figure 20 As shown, the cell further includes a main grid 5 extending along a first direction Y, the fine grid 4 is connected to the main grid 5, and at least part of the pad 2 is located on the main grid 5. In this case, the fine grid 4 and the pad 2 can be indirectly electrically connected through the main grid 5, or directly electrically connected to the pad 2.

[0221] like Figure 19 As shown, multiple main grids 5 are arranged at intervals along the second direction X, the number of main grids 5 in the second direction X is N4, 5≤N4≤24, and the number of main grids 5 in the second direction X can be 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24.

[0222] If the number of main grids 5 is small, the current collection efficiency is low, and the length of the fine grid 4 in the second direction Y is extended, thereby increasing the resistance during current transmission, thereby affecting the output power of the battery cell.

[0223] If the number of the busbars 5 is large, the busbars 5 will block a larger area of ​​the cell, thereby affecting the output power of the cell and increasing the slurry cost of the cell.

[0224] Therefore, 5≤N4≤24 improves the current collection efficiency of the battery cell and reduces the resistance during current transmission. At the same time, it reduces the shielding area of ​​the main grid 5 on the battery cell, which is beneficial to improving the output power of the battery cell and reducing the material cost of the battery cell.

[0225] like Figure 19 As shown, the pads 2 arranged along the first direction Y form a pad column 23 , and a plurality of pad columns 23 are arranged along the second direction X.

[0226] In some embodiments, in the second direction X, the number of the busbars 5 is the same as the number of the pad columns 23 , and the busbars 5 correspond to the pad columns 23 one-to-one, so as to improve the current collection efficiency of the solar cell.

[0227] In other embodiments, in the second direction X, the number of main grids 5 is less than the number of pad columns 23, that is, at least one pad column 23 that is not connected to the main grid 5 is included between two adjacent main grids 5. While reducing the number of main grids 5, the number of welding strips is increased, thereby improving the output power of the battery cell.

[0228] In some embodiments, the number of the main gate 5 in the first direction Y is one, that is, in the first direction Y, all the pads 2 in one pad column 23 are arranged on the same main gate 5 .

[0229] In other embodiments, multiple main grids 5 are arranged at intervals along the first direction Y, that is, in the first direction Y, some of the pads 2 in a pad column 23 are set on the main grid 5, and some of the pads 2 are not set on the main grid 5, so as to reduce the material cost of the main grid 5, and reduce the shading area of ​​the main grid 5 on the battery cell, thereby improving the output power of the battery cell.

[0230] A second aspect of the embodiments of the present application provides a photovoltaic module. Figure 21 The schematic diagram of the structure of the photovoltaic module provided in this application in some embodiments is as follows: Figure 21 As shown, the photovoltaic module includes a cover plate 10 , an encapsulation layer 20 and a cell layer 30 .

[0231] The cover plate 10 includes a first cover plate 101 and a second cover plate 102 arranged along a third direction Z, the packaging layer 20 and the battery layer 30 are located between the first cover plate 101 and the second cover plate 102, and a portion of the packaging layer 20 is located between the battery layer 30 and the first cover plate 101, and another portion of the packaging layer 20 is located between the battery layer 30 and the second cover plate 102, so as to realize the packaging and fixation of the cover plate 10 and the battery layer 30.

[0232] At least one of the first cover plate 101 and the second cover plate 102 is made of a light-transmitting material, which is beneficial to improving the photoelectric conversion efficiency of the photovoltaic module.

[0233] The material of the first cover plate 101 can be one of rigid materials such as tempered glass, PET (Polyethylene Terephthalate), PC (Polycarbonate). Alternatively, the material of the first cover plate 101 can be one of flexible materials such as PVF (Polyvinyl Fluoride), ETFE (Ethylene-Tetra-Fluoro-Ethylene), PVDF (Polyvinylidene Fluoride). All of the above materials have high light transmittance, which can ensure that more light is irradiated to the battery layer, thereby increasing the light absorption of the photovoltaic module and improving the photoelectric conversion efficiency of the photovoltaic module.

[0234] The second cover plate 102 may be made of a rigid material such as tempered glass, PET (Polyethylene Terephthalate), or PC (Polycarbonate). Alternatively, the second cover plate 102 may be made of a flexible material such as PVF (Polyvinyl Fluoride), ETFE (Ethylene-Tetra-Fluoro-Ethylene), or PVDF (Polyvinylidene Fluoride).

[0235] The materials of the first cover plate 101 and the second cover plate 102 may be the same or different.

[0236] like Figure 21 As shown, the encapsulation layer 20 includes a first adhesive film 201 and a second adhesive film 202. In the third direction Z, a portion of the first adhesive film 201 is located between the battery layer 30 and the first cover plate 101, and a portion of the second adhesive film 202 is located between the battery layer 30 and the second cover plate 102.

[0237] The material of the first adhesive film 201 is one of polyolefins, such as EVA (Ethylene-Vinyl Acetate Copolymer), POE (Polyolefin Elastomer), or PVB (Polyvinyl Butyral). These materials have high light transmittance, which helps improve the photovoltaic module's photoelectric conversion efficiency. The first adhesive film 201 can also be an EPE film (EVA-POE-EVA co-extruded structure) or an EP film (EVA-POE co-extruded structure).

[0238] The material of the second adhesive film 202 is one of polyolefins such as EVA (Ethylene-Vinyl Acetate Copolymer), POE (Polyolefin Elastomer), or PVB (Polyvinyl Butyral). The second adhesive film 202 can also be an EPE film (EVA-POE-EVA co-extruded structure) or an EP film (EVA-POE co-extruded structure).

[0239] The materials of the first adhesive film 201 and the second adhesive film 202 can be the same or different.

[0240] Figure 22 Schematic diagram of the connection structure of the battery layer in some embodiments, such as Figure 22As shown, the battery layer 30 includes multiple battery strings connected in series or in parallel, and each battery string is composed of multiple battery cells 301 connected in series. The battery cells 301 include but are not limited to monocrystalline silicon battery cells and polycrystalline silicon battery cells. Two adjacent battery cells 301 are connected by welding strips 302, and the welding strips 302 are welded and fixed to the pads on the battery cells 301. The battery cells 301 are the above-mentioned battery cells.

[0241] Figure 23 is a schematic diagram of the structure of the battery layer in some embodiments, such as Figure 23 As shown, the battery layer 30 further includes bus bars 303 . Along the first direction Y, the bus bars 303 are located on both sides of the battery string to realize series connection or parallel connection between multiple battery strings.

[0242] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A battery cell, characterized in that: The battery cell includes: A body (1), the body (1) further comprising a light-facing surface and a backlight surface distributed along the thickness direction of the battery cell; Solder pads (2), a plurality of the solder pads (2) are arranged along a first direction (Y), the solder pads (2) include an edge solder pad (21) located at the outermost side in the first direction (Y), and the solder pads (2) also include a middle solder pad (22), and in the first direction (Y), the middle solder pad (22) is located on one side of the edge solder pad (21); At least one of the light-facing surface and the backlight surface is provided with a harpoon structure (3); in the first direction (Y), the harpoon structure (3) is located on a side of the edge pad (21) facing away from the middle pad (22); and the harpoon structure (3) includes a harpoon gap (33); a fine grid (4) extending along a second direction (X), the fine grid (4) comprising a first fine grid (41) and a second fine grid (42); in the first direction (Y), the first fine grid (41) and the second fine grid (42) are both located on a side of the edge pad (21) facing away from the middle pad (22); and the first fine grid (41) is located between the second fine grid (42) and the edge pad (21); The first fine grid (41) and the second fine grid (42) are both connected to the harpoon structure (3), the first fine grid (41) is disconnected at the harpoon gap (33), and the second fine grid (42) passes through the harpoon gap (33) along the second direction (X).

2. The battery cell according to claim 1, wherein: In the first direction (Y), the cell includes an outermost edge fine grid (46), and the second fine grid (42) is configured as the edge fine grid (46).

3. The battery cell according to claim 1, wherein: The fine grid (4) further includes a third fine grid (43), and in the first direction (Y), the third fine grid (43) is located on a side of the second fine grid (42) away from the first fine grid (41); The third fine grid (43) is connected to the harpoon structure (3), and the third fine grid (43) is disconnected at the harpoon gap (33).

4. The battery cell according to claim 1, wherein: The body (1) comprises a first edge (11) and a second edge (12) arranged along the first direction (Y); the edge pad (21) comprises a first edge pad (211) and a second edge pad (212) arranged along the first direction (Y); in the first direction (Y), the first edge pad (211) is located between the first edge (11) and the second edge pad (212); In the first direction (Y), the harpoon structure (3), the first fine grid (41) and the second fine grid (42) are arranged between the first edge pad (211) and the first edge (11), and the harpoon structure (3), the first fine grid (41) and the second fine grid (42) are arranged between the second edge pad (212) and the second edge (12).

5. The battery cell according to claim 1, characterized in that: The body (1) comprises a first edge (11) and a second edge (12) arranged along the first direction (Y); the edge pad (21) comprises a first edge pad (211) and a second edge pad (212) arranged along the first direction (Y); in the first direction (Y), the first edge pad (211) is located between the first edge (11) and the second edge pad (212); In the first direction (Y), the harpoon structure (3) is provided between the first edge pad (211) and the first edge (11), and between the second edge pad (212) and the second edge (12); In the first direction (Y), the first fine grid (41) and the second fine grid (42) are located between the first edge pad (211) and the first edge (11); The fine grid (4) further includes a fourth fine grid (44), wherein in the first direction (Y), the fourth fine grid (44) is located between the second edge pad (212) and the second edge (12), the fourth fine grid (44) is connected to the harpoon structure (3), and the fourth fine grid (44) passes through the harpoon gap (33) along the second direction (X).

6. The battery cell according to claim 5, characterized in that: The fine grid (4) further includes a fifth fine grid (45), and in the first direction (Y), the fifth fine grid (45) is located between the fourth fine grid (44) and the second edge (12); The fifth fine grid (45) is connected to the harpoon structure (3), and the fifth fine grid (45) is disconnected at the harpoon gap (33).

7. The battery cell according to any one of claims 1 to 6, characterized in that: The middle pad (22) comprises a main pad (221) and a secondary pad (222), a plurality of the main pads (221) are arranged along the first direction (Y), and at least two secondary pads (222) are included between two adjacent main pads (221); In the thickness direction of the battery cell, the projected area of ​​the main pad (221) is larger than the projected area of ​​the auxiliary pad (222).

8. The battery cell according to claim 7, characterized in that: In the first direction (Y), at least three auxiliary pads (222) are included between the edge pad (21) and the main pad (221) adjacent thereto.

9. The battery cell according to claim 7, characterized in that: The outline shape of the main pad (221) is circular or rectangular; The outline shape of the auxiliary pad (222) is T-shaped, I-shaped or Z-shaped.

10. The battery cell according to any one of claims 1 to 6, characterized in that: In the first direction (Y), the number of the fine grids (4) between two adjacent pads (2) is 0, or at least one fine grid (4) is included between two adjacent pads (2); The pads (2) and the fine grids (4) are periodically arranged in the first direction (Y).

11. The battery cell according to claim 10, characterized in that: In the first direction (Y), the number of the fine grids (4) between two adjacent pads (2) is 0; The middle pad (22) comprises a main pad (221) and a secondary pad (222); in the thickness direction of the battery cell, the projected area of ​​the main pad (221) is larger than the projected area of ​​the secondary pad (222); The fine grid (4) comprises a main fine grid (48) and a secondary fine grid (49), the end of the main fine grid (48) contacts the main pad (221), and the end of the secondary fine grid (49) contacts the secondary pad (222); In the first direction (Y), the distance between the main fine grid (48) and the adjacent auxiliary fine grid (49) is L1, the distance between two adjacent auxiliary fine grids (49) is L2, and 0.3≤L1 / L2≤7.

12. The battery cell according to claim 11, characterized in that: 0.5mm≤L1≤2mm, 0.3mm≤L2≤1.5mm, and L2<L1.

13. The battery cell according to any one of claims 1 to 6, characterized in that: The cell is a main grid-less cell, and the welding pad (2) is directly connected to the fine grid (4).

14. The battery cell according to any one of claims 1 to 6, characterized in that: The cell further comprises a main grid (5) extending along the first direction (Y), the fine grid (4) is connected to the main grid (5), and at least part of the pad (2) is located on the main grid (5); A plurality of the main grids (5) are arranged at intervals along the second direction (X), and the number of the main grids (5) in the second direction (X) is N4, where 5≤N4≤24.

15. The battery cell according to claim 14, characterized in that: The pads (2) arranged along the first direction (Y) form a pad column (23), and a plurality of the pad columns (23) are arranged along the second direction (X); In the second direction (X), the number of the main grids (5) is the same as the number of the pad columns (23); Alternatively, in the second direction (X), the number of the main grids (5) is smaller than the number of the pad columns (23), and at least one pad column (23) is included between two adjacent main grids (5).

16. The battery cell according to any one of claims 1 to 6, characterized in that: The cell further comprises a main grid (5) extending along the first direction (Y), the fine grid (4) is connected to the main grid (5), and at least part of the pad (2) is located on the main grid (5); The number of the main grid (5) in the first direction (Y) is 1; Alternatively, a plurality of the main grids (5) are arranged at intervals along the first direction (Y).

17. A photovoltaic module, characterized in that: The photovoltaic module comprises a cover plate (10), an encapsulation layer (20) and a battery layer (30), wherein the battery layer (30) comprises a plurality of battery sheets according to any one of claims 1 to 16.

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