Battery cell

Abstract

The invention discloses a battery cell and electric equipment with the same. The battery cell comprises a diaphragm, a first adhesive tape and a plurality of pole pieces, the plurality of pole pieces comprise positive pole pieces and negative pole pieces, the diaphragm comprises an overlapping section and an idling section, the overlapping section is at least arranged between the positive pole pieces and the negative pole pieces and separates the positive pole pieces from the negative pole pieces along a Z shape, the overlapping section, the positive pole pieces and the negative pole pieces are overlapped to form an overlapping core, and the idling section is arranged between the overlapping section and the idling section. The idle section is connected with the tail end of the stacked section and surrounds the stacked core by at least one circle; the first adhesive tape is attached to the outside of the idle section, and the first adhesive tape at least wraps one side face of the stacked core and part of the idle section in the stacking direction of the stacked core. According to the battery cell provided by the invention, the idling section is arranged to surround the laminated core by at least one circle, so that the idling section can provide binding force for the laminated core to reduce the looseness of the internal pole pieces, so that an adhesive tape on the other side surface of the laminated core can be reduced or canceled, and the cost of the battery cell can be reduced.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a battery cell. Background Technology

[0002] In related technologies, battery cells using the "Z"-shaped stacking process have adhesive tape applied to both sides of the inner stacked core for fixation. The adhesive tape on both sides can prevent the battery cell from becoming loose and falling off due to the loosening of the inner electrode sheets. However, in order to ensure the fixation effect between the stacked cores, a large amount of adhesive tape is used, which makes the overall cost of the battery cell higher. Summary of the Invention

[0003] This application aims to at least partially address one of the aforementioned technical problems in the prior art. To this end, this application proposes a battery cell that helps reduce the amount of adhesive tape used and saves costs.

[0004] According to an embodiment of this application, a battery cell includes: a separator, a first adhesive tape, and a plurality of electrodes, the plurality of electrodes including a positive electrode and a negative electrode, the separator including a stacked section and an idle section, the stacked section being disposed at least between the positive electrode and the negative electrode, the stacked section separating the positive electrode and the negative electrode in a Z-shape, the stacked section, the positive electrode and the negative electrode being stacked to form a core, the idle section being connected to the end of the stacked section, the idle section surrounding the core at least once; the first adhesive tape is attached to the outside of the idle section, the first adhesive tape covering at least one side of the core and part of the idle section in the stacking direction of the core.

[0005] According to the embodiments of this application, the battery cell is provided with a free-spinning section that surrounds the stacked core at least once, so that the free-spinning section can provide binding force to the stacked core to reduce the loosening of the internal electrode sheets. This can reduce or eliminate the tape on the other side of the stacked core, which is beneficial to reducing the cost of the battery cell.

[0006] According to some embodiments of this application, each electrode includes an electrode body and an electrode tab, the electrode tab being connected to the electrode body, the idler section covering the stacked core in a direction surrounding a first direction, the first direction being the direction in which the electrode tab is connected to the electrode body; the first tape surrounds the first direction.

[0007] According to some embodiments of this application, the end of the idle section is located on one side of the stacked core in a second direction, the first tape and the end of the idle section are located on the same side of the stacked core, the first tape surrounds and covers the end of the idle section in the first direction, and the second direction is perpendicular to the first direction and perpendicular to the stacking direction of the stacked core.

[0008] According to some embodiments of this application, the battery cell further includes a second adhesive tape located on the other side of the stacked core in a second direction, the second adhesive tape surrounding the first direction, the second adhesive tape being attached to the outside of the idle section, and the second adhesive tape covering at least the other side of the stacked core and part of the idle section in the stacking direction of the stacked core.

[0009] According to some embodiments of this application, there are multiple first tapes, which are spaced apart in the first direction, and the number of second tapes is less than the number of first tapes.

[0010] According to some embodiments of this application, the tabs of all the electrodes are located at the same end of the electrode body in the first direction, and the second tape is one, located at the end of the electrode body that connects to the tab.

[0011] According to some embodiments of this application, the electrode tabs include positive electrode tabs and negative electrode tabs. In the stacking direction of the stacked cores, all the positive electrode tabs are stacked and all the negative electrode tabs are stacked. In the second direction, the positive electrode tabs and the negative electrode tabs are spaced apart.

[0012] According to some embodiments of this application, the electrode body includes a negative electrode body and a positive electrode body. On the large surface of the stacked core, the size of the separator is larger than the size of the negative electrode body, and the size of the negative electrode body is larger than the size of the positive electrode body.

[0013] According to some embodiments of this application, the edge of the diaphragm near the tab is the tab end edge. In the first direction, the distance of the second tape from the tab end edge is not less than the sum of the distance of the positive electrode body from the same end edge of the negative electrode body and the distance of the negative electrode body from the tab end edge.

[0014] According to some embodiments of this application, both the first tape and the second tape are constructed in a "C" shape.

[0015] According to some embodiments of this application, in the second direction, the length of the second tape is greater than the difference in size between the positive electrode body and the negative electrode body in the second direction. Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the stacked end faces of the battery cells according to an embodiment of this application;

[0017] Figure 2 This is a top view of a battery cell according to an embodiment of this application;

[0018] Figure 3 This is a side view of a battery cell according to an embodiment of this application;

[0019] Figure 4 This is a top view of the positive electrode plate;

[0020] Figure 5 This is a top view of the negative electrode plate;

[0021] Figure 6 This is a schematic diagram showing the relative positions of the second tape, the positive electrode body, the negative electrode body, and the separator;

[0022] Figure 7 This is a schematic diagram of the idle section without surrounding the core.

[0023] Figure label:

[0024] 10. Cell 1, electrode 1, positive electrode 11, positive electrode body 111, positive electrode edge 1111, positive electrode tab 112, negative electrode 12, negative electrode body 121, negative electrode edge 1211, negative electrode tab 122, electrode body 13, tab 14, separator 2, stacked section 21, idle section 22, tab end edge 23, first tape 3, second tape 4, stacked core 5, first side 51, second side 52, first large surface 53, second large surface 54, first end face 55, second end face 56. Detailed Implementation

[0025] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0026] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0027] The following is combined Figures 1-7 Detailed description of the battery cell 10 according to an embodiment of this application.

[0028] Reference Figures 1-2 As shown, the battery cell 10 according to an embodiment of this application may include: a separator 2, a first adhesive tape 3, and a plurality of electrode sheets 1.

[0029] The plurality of electrodes 1 include positive electrode 11 and negative electrode 12. There is at least one positive electrode 11 and at least one negative electrode 12. When the electrodes 1 are stacked, m positive electrode 11s can form a positive electrode group, and n negative electrode 12s can form a negative electrode group. The positive and negative electrode groups are stacked alternately, where m and n are positive integers such as 1, 2, 3, etc. The number of positive electrode 11s in different positions of the positive electrode group can be equal or unequal. The number of negative electrode 12s in different positions of the negative electrode group can also be equal or unequal. For example, they can be stacked in the form of 3 positive electrode 11s, 2 negative electrode 12s, 4 positive electrode 11s, and 3 negative electrode 12s, or in the form of 3 positive electrode 11s, 2 negative electrode 12s, 3 positive electrode 11s, and 2 negative electrode 12s. Adjacent positive electrode groups and negative electrode groups are separated by a membrane 2 to prevent short circuits caused by contact between positive electrode 11 and negative electrode 12.

[0030] In some embodiments, the positive electrode 11 and the negative electrode 12 can be stacked alternately in sequence, for example: the negative electrode 12, the positive electrode 11, the negative electrode 12, the positive electrode 11, the negative electrode 12, the positive electrode 11, the negative electrode 12, etc., are stacked alternately in sequence, such as... Figure 1 As shown.

[0031] Reference Figures 1-2 As shown, the separator 2 includes a stacking section 21 and an idler section 22. The stacking section 21 is disposed at least between the positive electrode 11 and the negative electrode 12, and the stacking section 21 separates the positive electrode 11 and the negative electrode 12 in a Z-shape. After the stacking section 21, the positive electrode 11, and the negative electrode 12 are stacked, a core 5 is formed. The idler section 22 is connected to the end of the stacking section 21 and surrounds the core 5 at least once. The idler section 22 can provide a binding force to the core 5 to reduce the loosening of the internal electrode 1.

[0032] In some embodiments, the number of turns of the idle segment 22 around the core 5 is 1, such as... Figure 1 As shown.

[0033] In other embodiments, the number of turns of the idle segment 22 around the core 5 is 2, 3, 4 or more.

[0034] The first adhesive tape 3 is applied to the outside of the idle section 22, and the first adhesive tape 3 covers at least one side of the stacked core 5 and part of the idle section 22 in the stacking direction of the core 5. It should be noted that the "stacking direction of the core 5" refers to the stacking direction of the positive electrode 11 and the negative electrode 12, that is... Figure 1 In the F5-F6 direction. The first tape 3 covers at least one side of the stacked core 5 and part of the idle section 22 from the outside of the idle section 22 in the F5-F6 direction. In this way, the binding force of the first tape 3 on the stacked core 5 makes the stacked core 5 structure compact and the multiple electrode sheets 1 are not easy to loosen.

[0035] After the electrode 1 is stacked and finished using the "Z" shaped stacking process, the separator 2 can be idled for at least one turn before finishing. The finishing tension of the separator 2 can bind the entire stack 5 together. The first tape 3 can be set only on one side of the stack 5, thereby reducing or eliminating the tape on the other side of the stack 5, which can effectively reduce the cost of the entire cell 10.

[0036] Reference Figures 1-2 and Figure 7 As shown, the stacked core 5 has a first side surface 51, a second side surface 52, a first large surface 53, a second large surface 54, a first end surface 55, and a second end surface 56. The first side surface 51 and the second side surface 52 are arranged opposite each other, the first large surface 53 and the second large surface 54 are arranged opposite each other, and the first end surface 55 and the second end surface 56 are arranged opposite each other. The idle section 22 can sequentially surround the first large surface 53, the second side surface 52, the second large surface 54, and the first side surface 51. The first adhesive tape 3 wraps around the first side surface 51 and the idle section 22 of the stacked core 5 from the outside of the idle section 22 in the F5-F6 direction, thereby reducing or eliminating the need for adhesive tape on the second side surface 52 of the stacked core 5, saving the cost of the battery cell 10.

[0037] According to the embodiments of this application, the battery cell 10 is provided with a free-spinning section 22 that surrounds the stacked core 5 at least once, so that the free-spinning section 22 can provide a binding force to the stacked core 5 to reduce the loosening of the internal electrode 1. This can reduce or eliminate the tape on the other side of the stacked core 5, which is beneficial to reducing the cost of the battery cell 10.

[0038] In some embodiments of this application, reference is made to Figures 1-2 As shown, each electrode 1 includes an electrode body 13 and an electrode tab 14. The electrode tab 14 is connected to the electrode body 13. The idle section 22 covers the stacked core 5 in a direction surrounding a first direction, which is the direction in which the electrode tab 14 is connected to the electrode body 13. A first adhesive tape 3 surrounds the first direction. The first direction is... Figures 2-6 The F1-F2 directions are the directions surrounding the first direction. Figure 1 In the F0 direction, the idle section 22 covers the stacked core 5 in the F0 direction, and the first tape 3 surrounds the first direction along the F0 direction. In other words, the first tape 3 covers the first side 51 of the stacked core 5 and the idle section 22 along the F0 direction.

[0039] In some embodiments of this application, the tabs 14 of a plurality of electrodes 1 are located at at least one end of the electrode body 13 in a first direction. Optionally, the tabs 14 of a plurality of electrodes 1 are located at the same end of the electrode body 13 in the first direction, such as... Figures 2-3As shown, the tabs 14 of multiple electrodes 1 are all located at the F2 end of the electrode body 13. Alternatively, some tabs 14 of electrodes 1 are located at the first end (such as the F1 end) of the electrode body 13 in the first direction, and other tabs 14 of electrodes 1 are located at the second end (such as the F2 end) of the electrode body 13 in the first direction.

[0040] In some embodiments of this application, the end 220 of the idle section 22 is located on one side of the stacked core 5 in the second direction, the first tape 3 is located on the same side of the stacked core 5 as the end 220 of the idle section 22, the first tape 3 wraps around the end 220 of the idle section 22 in the first direction, the second direction is perpendicular to the first direction and the second direction is perpendicular to the stacking direction of the stacked core 5, and the second direction, the first direction and the stacking direction of the stacked core 5 are perpendicular to each other.

[0041] Reference Figures 1-2 As shown, the second direction is F3-F4, the first direction is F1-F2, the stacking direction of the core 5 is F5-F6, and the direction surrounding the first direction is... Figure 1 In the F0 direction, the end 220 of the idle section 22 is located on the F3 side of the stacked core 5. The end 220 of the idle section 22 is formed as an edge extending along the F1-F2 direction. The first adhesive tape 3 is also located on the F3 side of the stacked core 5. The first adhesive tape 3 covers the end 220 of the idle section 22 in the F0 direction, fixing the end 220 of the idle section 22 to the idle section 22. The end 220 of the idle section 22 is the tail side of the separator 2. The fixation of the end 220 of the idle section 22 by the first adhesive tape 3 can effectively prevent the end 220 of the idle section 22 from curling. The idle section 22 can better bind the stacked core 5, thereby reducing or eliminating the adhesive tape on the non-separator tail side, which can effectively reduce the cost of the entire cell 10.

[0042] In some embodiments of this application, the battery cell 10 further includes a second adhesive tape 4 located on the other side of the stacked core 5 in the second direction. The second adhesive tape 4 surrounds the first direction and is attached to the outside of the idle section 22. The second adhesive tape 4 covers at least the other side of the stacked core 5 and a portion of the idle section 22 in the stacking direction of the stacked core 5. (Refer to...) Figures 1-3 As shown, the second tape 4 is located on the F4 side of the stacked core 5, and the first tape 3 covers the second side 52 of the stacked core 5 and part of the idle section 22 from the outside of the idle section 22 at least in the F5-F6 direction. In this way, the binding force of the second tape 4 on the stacked core 5 makes the structure of the stacked core 5 more compact at the second side 52, and the multiple electrode sheets 1 are not easy to loosen.

[0043] In some embodiments of this application, there are multiple first adhesive tapes 3, which are spaced apart in a first direction, and the number of second adhesive tapes 4 is less than the number of first adhesive tapes 3. (Refer to...) Figure 2As shown, there are four first tapes 3, which are arranged at intervals in the F1-F2 direction, so that the fixing force of the first tapes 3 on the first side 51 and the idle section 22 of the stacked core 5 is more uniform and the fixing effect is better. There is one second tape 4.

[0044] In some embodiments of this application, the tabs 14 of all electrodes 1 are located at the same end of the electrode body 13 in a first direction, and there is only one second adhesive tape 4, located at one end of the electrode body 13 connecting the tabs 14. Figures 2-3 As shown, the tabs 14 of all electrodes 1 are located at the F2 end of the electrode body 13, and there is one second adhesive tape 4, which is also located at the F2 end of the electrode body 13. This is because, due to the influence of the coating slurry, the thickness of the tab 14 is less than the thickness of the electrode body 13, and the area of ​​the tab 14 is the electrode thinning area. In traditional cells with tabs on the same side, due to the multi-layer accumulation of electrodes 1, the thickness of the stacked core 5 near the tab side is less than the thickness of the non-tab side. Therefore, it is necessary to apply the second adhesive tape 4 near the tab side to strengthen the adhesion between the positive electrode 11 and the negative electrode 12, and to avoid lithium plating caused by the expansion of the electrode 1 in the later stages of cell 10 cycling due to excessive gap between the positive electrode 11 and the negative electrode 12, which would affect the service life of the cell 10. Therefore, the second tape 4 is attached to the end of the electrode body 13 where the tab 14 is connected. This attachment position can strengthen the bonding between the positive electrode 11 and the negative electrode 12, and reduce the risk of rapid degradation of the lifespan of the cell 10 caused by lithium plating of the negative electrode 12 in the later stages of cycling.

[0045] In some embodiments of this application, the tab 14 includes a positive tab 112 and a negative tab 122. In the stacking direction of the core stack 5, all positive tabs 112 are stacked, and all negative tabs 122 are stacked. In a second direction, the positive tabs 112 and negative tabs 122 are spaced apart. Figure 2 , Figures 4-5 As shown, the positive electrode 11 includes a positive electrode body 111 and a positive electrode tab 112, and the negative electrode 12 includes a negative electrode body 121 and a negative electrode tab 122. In the F5-F6 direction, all positive electrode tabs 112 are stacked and all negative electrode tabs 122 are stacked. In the F3-F4 direction, the positive electrode tabs 112 and the negative electrode tabs 122 are spaced apart.

[0046] In some embodiments of this application, such as Figure 2 , Figures 4-5 As shown, the positive tabs 112 of all positive electrode plates 11 are stacked and close to the first side 51 of the stack core 5, and the negative tabs 122 of all negative electrode plates 12 are stacked and close to the second side 52 of the stack core 5.

[0047] In some other embodiments not shown in the figure, the positive tabs 112 of all positive electrode sheets 11 are stacked and close to the second side 52 of the core 5, and the negative tabs 122 of all negative electrode sheets 12 are stacked and close to the first side 51 of the core 5.

[0048] In some embodiments of this application, the electrode body 13 includes a negative electrode body 121 and a positive electrode body 111. On the large surface of the stacked core 5, the size of the separator 2 is larger than the size of the negative electrode body 121, and the size of the negative electrode body 121 is larger than the size of the positive electrode body 111. In the direction along F0, the second adhesive tape 4 simultaneously wraps around the positive electrode body 111, the negative electrode body 121, and the separator 2, thereby enabling the second adhesive tape 4 to simultaneously provide binding force to the positive electrode body 111, the negative electrode body 121, and the separator 2 to prevent the electrode 1 from loosening.

[0049] Specifically, on the large surface of the stacked core 5, in any direction, the size of the separator 2 in that direction is larger than the size of the negative electrode body 121 in that direction, and the size of the negative electrode body 121 in that direction is larger than the size of the positive electrode body 111 in that direction.

[0050] For example, in some embodiments of this application, in the first direction, the size of the separator 2 is larger than the size of the negative electrode body 121, and the size of the negative electrode body 121 is larger than the size of the positive electrode body 111. Figure 6 As shown, in the F1-F2 direction, both ends of the separator 2 extend beyond both ends of the negative electrode body 121, and both ends of the negative electrode body 121 extend beyond both ends of the positive electrode body 111. The separator 2 can effectively separate the positive electrode body 111 from the adjacent negative electrode body 121, and the negative electrode body 121 can completely cover the positive electrode body 111, thereby improving the safety performance of the cell 10.

[0051] For example, in some embodiments of this application, in the second direction, the size of the separator 2 is larger than the size of the negative electrode body 121, and the size of the negative electrode body 121 is larger than the size of the positive electrode body 111. Figure 6 As shown, in the F3-F4 direction, both ends of the separator 2 extend beyond both ends of the negative electrode body 121, and both ends of the negative electrode body 121 extend beyond both ends of the positive electrode body 111. The separator 2 can effectively separate the positive electrode body 111 from the adjacent negative electrode body 121, and the negative electrode body 121 can completely cover the positive electrode body 111, thereby improving the safety performance of the cell 10.

[0052] In some embodiments of this application, reference is made to Figure 6As shown, the edge of the diaphragm 2 near the tab 14 is the tab edge 23. In the first direction, the distance of the second tape 4 from the tab edge 23 is not less than the sum of the distance between the positive electrode body 111 and the negative electrode body 121 at the same end edge, and the distance between the negative electrode body 121 and the tab edge 23. Specifically, the F2 end edge of the diaphragm 2 is the tab edge 23, the F2 end edge of the negative electrode body 121 is the negative electrode edge 1211, and the F2 end edge of the positive electrode body 111 is the positive electrode edge 1111. The positive electrode edge 1111 and the negative electrode edge 1211 are parallel to the tab edge 23, and the distance of the second tape 4 from the tab edge 23 is not less than the sum of the distance between the positive electrode edge 1111 and the negative electrode edge 1211, and the distance between the negative electrode edge 1211 and the tab edge 23.

[0053] In other words, in the direction from F1 to F2, the distance between the second tape 4 and the F2 end edge of the separator 2 is not less than the sum of the distance between the positive electrode body 111 and the F2 end edge of the negative electrode body 121 and the distance between the negative electrode body 121 and the F2 end edge of the separator 2. Figure 6 As shown, the distance between the positive electrode body 111 and the F2 end edge of the negative electrode body 121 is H1, the distance between the negative electrode body 121 and the F2 end edge of the separator 2 is H2, and the distance between the second tape 4 and the F2 end edge of the separator 2 is H, where H≥H1+H2. This ensures that the second tape 4 can simultaneously wrap around the positive electrode body 111, the negative electrode body 121, and the separator 2 in the direction along F0.

[0054] In some embodiments of this application, reference is made to Figure 1 As shown, both the first tape 3 and the second tape 4 are constructed in a "C" shape. Thus, the first tape 3 can simultaneously wrap around the stacked core 5 and the idle section 22 from three directions, such as from the top, bottom and the first side 51 of the stacked core 5, resulting in a better fixing effect. Similarly, the second tape 4 can simultaneously wrap around the stacked core 5 and the idle section 22 from three directions, such as from the top, bottom and the second side 52 of the stacked core 5, resulting in a better fixing effect.

[0055] In some embodiments of this application, in the second direction, the length of the second tape 4 is greater than the difference in size between the positive electrode body 111 and the negative electrode body 121 in the second direction. This ensures that when the second tape 4 is attached to the outside of the idle section 22, it can cover as much of the positive electrode body 111 and the negative electrode body 121 as possible at the same time, thereby making the structure of the stacked core 5 more compact at the second side 52, and making it less likely for the positive electrode 111 and the negative electrode 121 to become relatively loose.

[0056] In some embodiments of this application, the end 220 of the idling section 22 is located at the same position as the end of the stacked section 21. In other words, the diaphragm 2 idles at least one revolution before ending at the original position, thereby ensuring that the number of revolutions of the idling section 22 is a positive integer.

[0057] Battery cell 10 can be used in electrical equipment. Optionally, the electrical equipment can be vehicles, ships, aircraft, machine tools, household appliances, etc.

[0058] In the description of this application, it should be understood that the terms "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0059] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0060] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0061] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A battery cell (10), characterized in that, include: Multiple electrodes (1), the multiple electrodes (1) including a positive electrode (11) and a negative electrode (12); A separator (2) is provided, comprising a stacked section (21) and an idle section (22). The stacked section (21) is disposed at least between the positive electrode (11) and the negative electrode (12). The stacked section (21) separates the positive electrode (11) and the negative electrode (12) in a Z-shape. The stacked section (21), the positive electrode (11) and the negative electrode (12) are stacked to form a core (5). The idle section (22) is connected to the end of the stacked section (21) and the idle section (22) surrounds the core (5) at least once. A first tape (3) is attached to the outside of the idle section (22), and the first tape (3) covers at least one side of the stacked core (5) and part of the idle section (22) in the stacking direction of the stacked core (5).

2. The battery cell (10) according to claim 1, characterized in that, Each electrode (1) includes an electrode body (13) and an electrode tab (14). The electrode tab (14) is connected to the electrode body (13). The idle section (22) covers the stacked core (5) in a direction surrounding a first direction, which is the direction in which the electrode tab (14) is connected to the electrode body (13). The first tape (3) surrounds the first direction.

3. The battery cell (10) according to claim 2, characterized in that, The end of the idle section (22) is located on one side of the stacked core (5) in the second direction. The first tape (3) is located on the same side of the stacked core (5) as the end of the idle section (22). The first tape (3) wraps around the end of the idle section (22) in the first direction. The second direction is perpendicular to the first direction and perpendicular to the stacking direction of the stacked core (5).

4. The battery cell (10) according to claim 3, characterized in that, The cell (10) further includes a second tape (4) located on the other side of the stacked core (5) in the second direction. The second tape (4) surrounds the first direction and is attached to the outside of the idle section (22). The second tape (4) covers at least the other side of the stacked core (5) and part of the idle section (22) in the stacking direction of the stacked core (5).

5. The battery cell (10) according to claim 4, characterized in that, There are multiple first tapes (3), and the multiple first tapes (3) are arranged at intervals in the first direction. The number of second tapes (4) is less than the number of first tapes (3).

6. The battery cell (10) according to claim 4, characterized in that, The tabs (14) of all the electrodes (1) are located at the same end of the electrode body (13) in the first direction, and there is one second tape (4) located at the end of the electrode body (13) that connects to the tabs (14).

7. The battery cell (10) according to claim 6, characterized in that, The tab (14) includes a positive tab (112) and a negative tab (122). In the stacking direction of the stacked core (5), all the positive tabs (112) are stacked and all the negative tabs (122) are stacked. In the second direction, the positive tabs (112) and the negative tabs (122) are spaced apart.

8. The battery cell (10) according to claim 6 or 7, characterized in that, The electrode body (13) includes a negative electrode body (121) and a positive electrode body (111). On the large surface of the stacked core (5), the size of the separator (2) is larger than the size of the negative electrode body (121), and the size of the negative electrode body (121) is larger than the size of the positive electrode body (111).

9. The battery cell (10) according to claim 8, characterized in that, The edge of the diaphragm (2) near the tab (14) is the tab end edge. In the first direction, the distance of the second tape (4) from the tab end edge is not less than the sum of the distance of the positive electrode body (111) from the same end edge of the negative electrode body (121) and the distance of the negative electrode body (121) from the tab end edge.

10. The battery cell (10) according to claim 4, characterized in that, Both the first tape (3) and the second tape (4) are constructed in a "C" shape.

11. The battery cell (10) according to claim 8, characterized in that, In the second direction, the length of the second tape (4) is greater than the difference in size between the positive electrode body (111) and the negative electrode body (121) in the second direction.

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