Battery piece, battery string and laminated assembly
By providing the first and second gate lines of the changing direction on the cell, the problem of low density of stacked components in the traditional technology is solved, and a higher structural density and energy density are achieved.
Patent Information
- Application Number
- CN202420456810.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-11
- Publication Date
- 2025-02-28
- Estimated Expiration
- 2034-03-11
AI Technical Summary
When building stacked components, traditional back contact solar cells need to use head-to-tail welding of bus bars, resulting in a large proportion of bus bar space and reducing the density of stacked components.
By providing the first gate line and the second gate line on the battery cell, they are electrically connected to the sheet body and extend to the edge of the sheet body respectively to realize the direction of the main gate. The first gate line is used to build a battery string, while the second gate line in a direction is used to electrically connect with other battery strings, reducing the use of bus bars and space occupancy.
This solution reduces the use of bus bars at the end of the battery string, reduces the space occupied by bus bars at the end of the battery string, and improves the structural density and energy density of the stacked assembly.
Smart Images
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Abstract
Description
Technical Field
[0001] The present application relates to the field of photovoltaic technology, and in particular to solar cells, solar cell strings and stacked components. Background Art
[0002] With the continuous development of science and technology, solar cells, as a kind of complex energy, have also developed rapidly.
[0003] The positive and negative electrode main grids of traditional BC (Back Contact) batteries are arranged in a straight line on the back of the battery cell. When making a stacked component, first, multiple battery cells are arranged in rows, and the adjacent positive and negative electrode main grids are welded through interconnection bars by welding, and the single battery cells are connected in series to form a battery string. Then, multiple battery strings are arranged in columns, and the interconnection bars at the head and tail of two adjacent battery strings are connected through bus bars to construct a stacked component. That is, when the battery strings are stacked, the bus bars are welded at the head and tail, and the bus bar space occupies a large proportion, making the density of the stacked component low. Summary of the invention
[0004] Based on this, it is necessary to provide a battery cell, battery string and stacking assembly to address the problem that when stacking battery strings, the bus bars are welded at the head and tail, which occupies a large space and makes the density of the stacking assembly low.
[0005] The embodiment of the first aspect of the present application provides a battery cell, including:
[0006] A sheet, wherein a first edge is disposed at one end of the sheet along a first direction, a second edge is disposed at one end of the sheet along a second direction, and an angle is disposed between the first direction and the second direction;
[0007] A first grid line, wherein the first grid line is disposed on the sheet body, and the first grid line extends toward the first edge to be electrically connected to other battery sheets to construct a battery string; and
[0008] A second grid line is arranged on the sheet, one end of the second grid line is used to be electrically connected to the first grid line, and the other end extends toward the second edge to be used to be electrically connected to another second grid line in another battery string to construct a stacked component.
[0009] In one embodiment, the angle between the first direction and the second direction is configured to be 90 degrees.
[0010] In one embodiment, the first gate line and the second gate line are perpendicular to each other.
[0011] In one embodiment, the first gate line and the second gate line are both disposed on the back side of the sheet.
[0012] In one embodiment, adjacent battery cells are electrically connected via welding strips, and the connection between the first grid line and the second grid line is configured to be arc-shaped.
[0013] In one embodiment, adjacent battery cells are electrically connected via a printed circuit board.
[0014] In one embodiment, the sheet body is configured as a whole sheet structure, or the sheet body is configured as a half sheet structure.
[0015] An embodiment of the second aspect of the present application provides a battery string, comprising:
[0016] A first battery cell, wherein the first battery cell is configured as the battery cell as described in any of the above embodiments; and
[0017] A plurality of second battery cells, each of which is provided with a third grid line, and the third grid line is used to be electrically connected to the first grid line in the first battery cell and / or to be electrically connected to the third grid line in an adjacent second battery cell.
[0018] An embodiment of the third aspect of the present application provides a stacking assembly, comprising a plurality of battery strings as described in the above embodiments, wherein the plurality of battery strings are arranged and connected in series.
[0019] In one embodiment, the battery string is arranged along the second direction, and the battery string includes:
[0020] two battery header strings; and
[0021] A plurality of battery middle strings, wherein the battery middle strings include two first battery cells arranged at the ends of the battery middle strings and a plurality of second battery cells connected in series between the two first battery cells; the second grid lines in the two first battery cells extend along the second direction of the battery middle strings at both ends respectively, and are used to electrically connect the second grid lines in the adjacent battery middle strings or the battery head strings.
[0022] In one embodiment, the battery head string includes one first battery cell and a plurality of second battery cells connected in series;
[0023] One of the first battery cells is disposed at one end of the battery head string in the first direction; one of the second battery cells is disposed at the other end of the battery head string in the first direction, and the third grid line of the second battery cell is connected to a bus bar to construct an electrode;
[0024] The remaining second battery cells are connected in series along the first direction in the middle of the battery head string;
[0025] Wherein, the two electrodes of the stacked assembly are arranged on the same side of the stacked assembly.
[0026] In one embodiment, the battery head string includes two first battery cells and a plurality of second battery cells connected in series;
[0027] One of the first battery cells is disposed at one end of the battery head string in the first direction; another of the first battery cells is disposed at the other end of the battery head string in the first direction, and the second grid line of the first battery cell is connected to a bus bar to construct an electrode;
[0028] A plurality of the second battery cells are connected in series between two of the first battery cells along the first direction;
[0029] Wherein, the two electrodes of the stacked assembly are disposed on two sides of the stacked assembly.
[0030] According to the battery cell, battery string and laminated assembly of the embodiment of the present application, after the first grid line and the second grid line are electrically connected on the sheet body, they extend to the first edge and the second edge of the sheet body respectively, realizing the change of direction of the main grid on the battery cell. Among them, the first grid line can be used to electrically connect with other battery cells when constructing the battery string to construct the battery string; and the second grid line with a change of direction can enable the battery string to be electrically connected to other battery strings through the second grid line when constructing the laminated assembly to construct the laminated assembly. The embodiment of the present application changes the direction of the main grid of the battery cell on the sheet body through the first grid line and the second grid line, improving the solution in the traditional technology that requires the bus bar to be connected at the end of the first direction of the battery string before it can be electrically connected to other battery strings. The second grid line can be electrically connected to other battery strings at one end of the second direction of the battery string. When the battery string is used to construct the laminated assembly, the use of the bus bar at the end of the first direction of the battery string is reduced, and the space occupied by the bus bar at the end of the first direction of the battery string is also reduced, thereby improving the structural density of the laminated assembly and the energy density of the laminated assembly. BRIEF DESCRIPTION OF THE DRAWINGS
[0031] FIG. 1 is a schematic diagram of the structure of a battery cell according to an embodiment of the present application.
[0032] FIG. 2 is a schematic diagram of a structure of a stacked assembly constructed by using the battery cells in FIG. 1 according to an embodiment of the present application.
[0033] FIG3 is a schematic diagram of the structure of a battery cell in a stacked assembly according to an embodiment of the present application when the first grid line and the second grid line are not perpendicular to each other.
[0034] FIG. 4 is a schematic structural diagram of a battery cell in an embodiment of the present application in which a portion where a first gate line and a second gate line are connected is configured to be in an arc shape.
[0035] FIG. 5 is a schematic structural diagram of a stacked assembly according to an embodiment of the present application when the sheet body is a half-sheet structure.
[0036] FIG. 6 is a schematic diagram of the structure of a battery string according to an embodiment of the present application.
[0037] FIG. 7 is a schematic structural diagram of a stacked assembly according to an embodiment of the present application.
[0038] FIG. 8 is a schematic structural diagram of a stacked assembly in which two electrodes are disposed on the same side of the stacked assembly according to an embodiment of the present application.
[0039] FIG. 9 is a partial enlarged schematic diagram of point A in FIG. 8 .
[0040] FIG. 10 is a schematic structural diagram of a stacked assembly in which two electrodes are disposed on two sides of the stacked assembly in one embodiment of the present application.
[0041] FIG. 11 is a partial enlarged schematic diagram of point B in FIG. 10 .
[0042] Reference numerals:
[0043] 10. Battery string;
[0044] 11. Battery cell; 110. First battery cell;
[0045] 111, sheet body; 1111, first edge; 1112, second edge; 1113, first grid line; 1114, second grid line;
[0046] 12. second battery cell; 121. third grid line;
[0047] 13. Battery head string;
[0048] 14. The middle part of the battery string;
[0049] 15. Bus bar;
[0050] 16. Electrode. DETAILED DESCRIPTION
[0051] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.
[0052] In the description of the present application, it should be understood that if the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. appear, the orientation or position relationship indicated by these terms is based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.
[0053] In addition, if the terms "first" or "second" appear, these terms are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, if the term "plurality" appears, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.
[0054] In this application, unless otherwise clearly specified and limited, if the terms "installed", "connected", "connected", "fixed" and the like appear, these terms should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.
[0055] In the present application, unless otherwise clearly specified and limited, if there is a description that a first feature is "above" or "below" a second feature, etc., or similar descriptions appear, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.
[0056] It should be noted that if an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. If an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. If any, the terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used in this application are for illustrative purposes only and do not represent the only implementation method.
[0057] Please refer to FIG. 1 , which shows a schematic structural diagram of a battery cell 11 according to an embodiment of the present application.
[0058] At least one embodiment of the present application provides a battery cell 11, including a sheet 111, a first grid line 1113 and a second grid line 1114. The sheet 111 is provided with a first edge 1111 at one end along a first direction, and the sheet 111 is provided with a second edge 1112 at one end along a second direction. An angle is provided between the first direction and the second direction. In some embodiments, the first direction is the X direction shown in the figure, and the second direction is the Y direction shown in the figure.
[0059] Referring to FIG. 1 and FIG. 2 , FIG. 2 shows a schematic diagram of a structure of a stacked assembly constructed by the battery cell 11 in FIG. 1 according to an embodiment of the present application. A first grid line 1113 is disposed on the sheet 111, and the first grid line 1113 extends toward the first edge 1111 for electrical connection with other battery cells 11 to construct a battery string 10. A second grid line 1114 is disposed on the sheet 111, and one end of the second grid line 1114 is used to be electrically connected to the first grid line 1113, and the other end extends toward the second edge 1112 for electrical connection with another second grid line 1114 in another battery string 10 to construct a stacked assembly.
[0060] According to the battery cell 11 of the embodiment of the present application, after the first grid line 1113 and the second grid line 1114 are electrically connected on the sheet 111, they extend to the first edge 1111 and the second edge 1112 of the sheet 111 respectively, thereby realizing the change of direction of the main grid on the battery cell 11. Among them, the first grid line 1113 can be used to electrically connect with other battery cells 11 when constructing a battery string 10 to construct a battery string 10; and the second grid line 1114 with a changed direction can enable the battery string 10 to be electrically connected with other battery strings 10 through the second grid line 1114 when constructing a stacked assembly to construct a stacked assembly. The embodiment of the present application changes the direction of the main grid of the battery cell 11 on the sheet 111 through the first grid line 1113 and the second grid line 1114, thereby improving the solution in the traditional technology that requires the bus bar 15 to be connected at the end of the battery string 10 in the first direction before it can be electrically connected to other battery strings 10. The second grid line 1114 can be electrically connected to other battery strings 10 at one end of the battery string 10 in the second direction. When the battery string 10 is used to construct a stacked assembly, the use of the bus bar 15 at the first direction end of the battery string 10 is reduced, and the space occupied by the bus bar 15 at the first direction end of the battery string 10 is also reduced, thereby improving the structural density of the stacked assembly and improving the energy density of the stacked assembly.
[0061] 1 and 2 , in some embodiments, the angle between the first direction and the second direction is 90 degrees. That is, a plurality of battery cells 11 are first arranged in rows in the first direction to form a battery string 10; and a plurality of battery strings 10 are then arranged in columns in the second direction to form a stacked assembly.
[0062] 1 and 2 , in some embodiments, the first gate line 1113 and the second gate line 1114 are perpendicular to each other, the first gate line 1113 is arranged along the first direction, and the second gate line 1114 is arranged along the second direction, that is, the angle between the first gate line 1113 and the second gate line 1114 is 90 degrees.
[0063] Refer to FIG. 3, which shows a schematic diagram of the structure when the first grid line 1113 and the second grid line 1114 in the battery cell 11 in the stacked assembly of one embodiment of the present application are not perpendicular to each other. In some embodiments, the first grid line 1113 and the second grid line 1114 may not be perpendicular, and an angle is set between the first grid line 1113 and the second grid line 1114. It can be understood that as long as the first grid line 1113 extends to the first edge 1111 for electrical connection with other battery cells 11 to construct a battery string 10, and the second grid line 1113 extends to the second edge 1112 for electrical connection with another second grid line 1114 in another battery string 10 to construct a stacked assembly.
[0064] In some embodiments, the first gate line 1113 and the second gate line 1114 are both disposed on the back side of the sheet 111. That is, the battery sheet 11 provided in the embodiment of the present application is configured as a BC battery.
[0065] Referring to Fig. 4, Fig. 4 shows a schematic diagram of a structure in which the first grid line 1113 and the second grid line 1114 in the battery cell 11 of an embodiment of the present application are arranged in an arc shape. In some embodiments, adjacent battery cells 11 are electrically connected via welding strips, and the first grid line 1113 and the second grid line 1114 are arranged in an arc shape at the connection point, which facilitates the arrangement of the welding strip during welding, improves welding efficiency, and ensures welding quality.
[0066] In some embodiments, adjacent battery cells 11 are electrically connected via a printed circuit board.
[0067] In some embodiments, the first gate line 1113 and the second gate line 1114 can be configured as a line shape, a broken line shape, or a dot shape.
[0068] 4 , in some embodiments, the sheet 111 is configured as a whole sheet structure. In the whole sheet structure, the cross section of the sheet 111 is square, and the length of the first edge 1111 is equal to the length of the second edge 1112 .
[0069] Referring to FIG. 5 , FIG. 5 shows a schematic diagram of a structure in which the sheet 111 in the laminate assembly of an embodiment of the present application is a half-sheet structure. In some embodiments, the sheet 111 is configured as a half-sheet structure. In the half-sheet structure, the cross-section of the sheet 111 is a long square, and the length of the first edge 1111 is equal to half the length of the second edge 1112. It is understood that in other embodiments, the length of the first edge 1111 and the length of the second edge 1112 of the sheet 111 can also be set to other ratios according to specific usage requirements.
[0070] Please refer to FIG. 6 , which shows a schematic structural diagram of a battery string 10 according to an embodiment of the present application.
[0071] At least one embodiment of the present application provides a battery string 10, including a first battery cell 110 and a plurality of second battery cells 12, wherein the first battery cell 110 is configured as a battery cell 11 in any of the above embodiments. The second battery cell 12 is provided with a third grid line 121, and the third grid line 121 is used to be electrically connected to the first grid line 1113 in the first battery cell 110, and / or to be electrically connected to the third grid line 121 in the adjacent second battery cell 12. The third grid line 121 is arranged along the first direction.
[0072] According to the battery string 10 of the embodiment of the present application, the main grid of the battery sheet 11 is changed on the sheet 111 through the first grid line 1113 and the second grid line 1114, which improves the solution in the traditional technology that requires the bus bar 15 to be connected at the end of the battery string 10 in the first direction to be electrically connected to other battery strings 10. The second grid line 1114 can be electrically connected to other battery strings 10 at one end of the battery string 10 in the second direction. When the battery string 10 is used to construct a stacked assembly, the use of the bus bar 15 at the end of the battery string 10 in the first direction is reduced, and the space occupied by the bus bar 15 at the end of the battery string 10 in the first direction is also reduced, thereby improving the structural density of the stacked assembly and the energy density of the stacked assembly.
[0073] Please refer to FIG. 7 , which shows a schematic structural diagram of a stacked assembly according to an embodiment of the present application.
[0074] At least one embodiment of the present application provides a stacked assembly, including a plurality of battery strings 10 according to the above embodiments, wherein the plurality of battery strings 10 are arranged and connected in series.
[0075] Refer to FIG8 , which shows a schematic diagram of the structure when two electrodes 16 are arranged on the same side of the laminate assembly in an embodiment of the present application. In some embodiments, the battery string 10 is arranged along the second direction, and the battery string 10 includes two battery head strings 13 and a plurality of battery middle strings 14, and the battery middle string 14 includes two first battery cells 110 arranged at the ends of the battery middle string 14 and a plurality of second battery cells 12 connected in series between the two first battery cells 110; the second grid lines 1114 in the two first battery cells 110 extend along the second direction of the battery middle string 14 at both ends, respectively, for electrically connecting the second grid lines 1114 in the adjacent battery middle string 14 or the battery head string 13.
[0076] Refer to Figures 8 and 9, Figure 9 shows a partial enlarged schematic diagram of A in Figure 8. In some embodiments, the battery head string 13 includes a first battery cell 110 and a plurality of second battery cells 12 connected in series. Among them, a first battery cell 110 is arranged at one end of the battery head string 13 in the first direction; a second battery cell 12 is arranged at the other end of the battery head string 13 in the first direction, and the third grid line 121 of the second battery cell 12 is connected to the bus bar 15 to construct an electrode 16; the remaining second battery cells 12 are connected in series in the middle of the battery head string 13 along the first direction. Among them, the two electrodes 16 of the stack assembly are arranged on the same side of the stack assembly.
[0077] In some embodiments, a plurality of positive main grids and negative main grids are provided on the battery sheet 11, wherein each positive main grid and each negative main grid include a first grid line 1113 and a second grid line 1114, and the positive main grid and the negative main grid can be evenly spaced and arranged on the sheet 111. When constructing a battery string 10 or constructing a stacked assembly, the positive main grid and the negative main grid between adjacent battery sheets 11 are electrically connected. It can be understood that when the third grid line 121 on the second battery sheet 12 is connected to the bus bar 15 to construct the electrode 16, the bus bar 15 in one battery head string 13 connects the third grid lines 121 of all positive main grids on the second battery sheet 12 to construct the positive electrode 16; the bus bar 15 in another battery head string 13 connects the third grid lines 121 of all negative main grids on the second battery sheet 12 to construct the negative electrode 16, so that the stacked assembly has a positive electrode motor and a negative electrode 16, which will not be repeated here.
[0078] Referring to Figures 10 and 11, Figure 10 shows a schematic diagram of a structure in which two electrodes 16 are placed on both sides of a laminate assembly in an embodiment of the present application. Figure 11 shows a partially enlarged schematic diagram at A in Figure 10. In some embodiments, the battery head string 13 includes two first battery cells 110 connected in series and a plurality of second battery cells 12. A first battery cell 110 is arranged at one end of the first direction of the battery head string 13; another first battery cell 110 is arranged at the other end of the first direction of the battery head string 13, and the second grid line 1114 of the first battery cell 110 is connected to a bus bar 15 to construct an electrode 16; a plurality of second battery cells 12 are connected in series between the two first battery cells 110 along the first direction. Among them, the two electrodes 16 of the laminate assembly are placed on both sides of the laminate assembly. It can be understood that the extension direction of the second grid line 1114 can be placed according to the specific use requirements of the laminate assembly to obtain electrodes 16 at different positions.
[0079] According to the laminated assembly of the embodiment of the present application, the main grid of the battery sheet 11 is changed on the sheet 111 by the first grid line 1113 and the second grid line 1114, which improves the solution in the conventional technology that requires the bus bar 15 to be connected at the end of the battery string 10 in the first direction to be electrically connected to other battery strings 10. The second grid line 1114 can be electrically connected to other battery strings 10 at one end of the battery string 10 in the second direction. When the battery string 10 is used to construct the laminated assembly, the use of the bus bar 15 at the end of the battery string 10 in the first direction is reduced, and the space occupied by the bus bar 15 at the end of the battery string 10 in the first direction is also reduced, thereby improving the structural density of the laminated assembly and the energy density of the laminated assembly.
[0080] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0081] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.
Claims
1. A battery cell, characterized in that: include: A sheet, wherein a first edge is disposed at one end of the sheet along a first direction, a second edge is disposed at one end of the sheet along a second direction, and an angle is disposed between the first direction and the second direction; A first grid line, wherein the first grid line is disposed on the sheet body, and the first grid line extends toward the first edge to be electrically connected to other battery sheets to construct a battery string; and A second grid line is arranged on the sheet, one end of the second grid line is used to be electrically connected to the first grid line, and the other end extends toward the second edge to be used to be electrically connected to another second grid line in another battery string to construct a stacked component.
2. The battery cell according to claim 1, characterized in that: The angle between the first direction and the second direction is configured to be 90 degrees.
3. The battery cell according to claim 2, characterized in that: The first gate line and the second gate line are perpendicular to each other.
4. The battery cell according to claim 1, characterized in that: The first gate lines and the second gate lines are both arranged on the back side of the sheet.
5. The battery cell according to claim 1, characterized in that: Adjacent battery cells are electrically connected via welding strips, and the connecting portion between the first grid line and the second grid line is configured to be arc-shaped.
6. The battery cell according to claim 1, characterized in that: Adjacent battery cells are electrically connected via a printed circuit board.
7. The battery cell according to any one of claims 1 to 6, characterized in that: The sheet body is configured as a whole sheet structure, or the sheet body is configured as a half sheet structure.
8. A battery string, characterized in that: include: A first battery cell, wherein the first battery cell is configured as a battery cell according to any one of claims 1 to 7; as well as A plurality of second battery cells, each of which is provided with a third grid line, and the third grid line is used to be electrically connected to the first grid line in the first battery cell and / or to be electrically connected to the third grid line in an adjacent second battery cell.
9. A laminate assembly, characterized in that: The invention comprises several battery strings as claimed in claim 8, wherein the several battery strings are arranged and connected in series.
10. The stack assembly according to claim 9, characterized in that The battery string is arranged along the second direction, and the battery string includes: two battery header strings; and A plurality of battery middle strings, wherein the battery middle strings include two first battery cells arranged at the ends of the battery middle strings and a plurality of second battery cells connected in series between the two first battery cells; the second grid lines in the two first battery cells extend along the second direction of the battery middle strings at both ends respectively, and are used to electrically connect the second grid lines in the adjacent battery middle strings or the battery head strings.
11. The stack assembly according to claim 10, characterized in that The battery head string includes one first battery cell and a plurality of second battery cells connected in series; One of the first battery cells is disposed at one end of the battery head string in the first direction; one of the second battery cells is disposed at the other end of the battery head string in the first direction, and the third grid line of the second battery cell is connected to a bus bar to construct an electrode; The remaining second battery cells are connected in series along the first direction in the middle of the battery head string; Wherein, the two electrodes of the stacked assembly are arranged on the same side of the stacked assembly.
12. The stack assembly according to claim 10, characterized in that The battery head string includes two first battery cells and a plurality of second battery cells connected in series; One of the first battery cells is disposed at one end of the battery head string in the first direction; another of the first battery cells is disposed at the other end of the battery head string in the first direction, and the second grid line of the first battery cell is connected to a bus bar to construct an electrode; A plurality of the second battery cells are connected in series between two of the first battery cells along the first direction; Wherein, the two electrodes of the stacked assembly are disposed on two sides of the stacked assembly.