Battery cell structure and square battery
By setting up a square winding battery cell structure side by side, weld dummy welding, pole expansion and safety hazards caused by excessive number of pole sheet stacking layers or core thickness/number in the existing battery cell structure are solved, and the effect of slowing pole sheet expansion, improving safety performance and reducing internal resistance is achieved.
Patent Information
- Application Number
- CN202421820053.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-29
- Publication Date
- 2025-06-17
- Estimated Expiration
- 2034-07-29
AI Technical Summary
The existing battery cell structure with positive and negative electrode ears at the top is in the stacking and winding batteries. The number of electrode sheet stacking layers or core thickness/number of coils is too large, resulting in safety hazards caused by welding dummy welding and expansion of electrode sheets and large-surface bulging problems.
A square winding battery cell structure arranged side by side is adopted. Through the side-by-side arrangement of the first battery cell and the second battery cell, the absolute thickness of the core is reduced, the absolute value of the expansion of the pole sheet is reduced, and the connection is carried out through a specific pole ear structure and the connecting piece is connected to ensure that the battery cell is arranged in parallel and internal resistance is reduced.
It slows down the problem of pole expansion, improves the safety performance of the battery, increases the heat dissipation area, improves the uniformity of temperature distribution, reduces the internal resistance of the battery, and broadens the application scenarios of the battery.
Smart Images
Figure CN222995744U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of batteries, and particularly to a core structure and a square battery. Background Art
[0002] With the continuous development of new energy technologies, square single batteries have a wide range of applications. Current square batteries are developing towards large capacity, large size, and large volume. Among them, the core structure with top-mounted tabs still has a wide range of applications. However, in the existing core structure with both positive and negative tabs emerging from the top simultaneously, either the positive and negative tabs emerge from the same side, or one side has a positive tab and the other side has a negative tab. These two structures are suitable for batteries using the stacking and winding methods, but they have the following disadvantages: 1) In the case of a stacking structure, the number of stacked electrode sheets is not easy to be too large; 2) In the case of a winding method, the thickness of the wound core or the number of wound cores (stacked) is not easy to be too large. The reason is that if the number of stacked electrode sheets, the thickness of the wound core, or the number of stacked wound cores is too large, first, there may be a problem of poor soldering; second, during the charge and discharge process of the core, the electrode sheets expand, especially in the later stage of cycling, the expansion force is relatively large, which makes the electrode sheets in the battery fit too tightly, and the internal electrolyte cannot enter the electrode sheets in time, resulting in lithium plating on the electrode sheets, and further bringing potential safety hazards; on the other hand, the relatively large expansion force of the electrode sheets causes the large surface of the battery to bulge. For a module or a pack, it may cause the steel belt that binds the battery in the module or pack to break, leading to safety problems. Summary of the Utility Model
[0003] Based on this, it is necessary to provide a core structure and a square battery with a relatively simple welding process, which can slow down the problem of electrode sheet expansion, solve the problem of poor soldering of the tabs, and have relatively good safety performance.
[0004] In a first aspect, the present application provides a core structure, including a first core and a second core. Both the first core and the second core are square wound cores; the first core and the second core are arranged side by side;
[0005] The first core extends out of a first tab and a second tab with opposite polarities on its top side, and the first core extends out of a third tab on its bottom side. The first tab and the third tab have the same polarity;
[0006] The second core extends out of a fourth tab and a fifth tab with the same polarity on its top side, and the second core extends out of a sixth tab on its bottom side. The fourth tab and the sixth tab have opposite polarities; and the third tab and the sixth tab have the same polarity;
[0007] The second tab and the fourth tab are connected by a first connecting piece, the third tab and the sixth tab are connected by a second connecting piece, and the first core and the second core as a whole output power through the first tab and the fifth tab.
[0008] In one embodiment, after the second tab and the fourth tab are welded to the first connecting piece, they are folded over and placed on the top side of the first battery cell and the second battery cell;
[0009] After the third tab and the sixth tab are welded to the second connecting piece, they are folded over and received on the bottom side of the first battery cell and the second battery cell.
[0010] In one embodiment, the second tab is adjacent to the fourth tab, and the third tab is adjacent to the sixth tab.
[0011] In one embodiment, at least one of the first tab, the second tab, the third tab, the fourth tab, the fifth tab, and the sixth tab has the following structure: the width of the tab gradually decreases in the extending direction, and the tab has an arc-shaped corner structure, and the tab is a multi-tab structure.
[0012] In one embodiment, the second tab is welded to the first end of the first connecting piece, and the fourth tab is welded to the second end of the first connecting piece;
[0013] And / or, the third tab is welded to the first end of the second connecting piece, and the sixth tab is welded to the second end of the second connecting piece.
[0014] In one embodiment, the first tab is a cathode tab, the second tab is an anode tab, the first connecting piece is a copper connecting piece, and the second connecting piece is an aluminum connecting piece.
[0015] In one embodiment, the first battery cell includes a first anode sheet, a first separator, and a first cathode sheet. The first anode sheet, the first separator, the first cathode sheet, and the first separator are stacked and wound with each other to form the first battery cell. The second tab extends from the top of the first anode sheet, the first tab extends from the top of the first cathode sheet, and the third tab extends from the bottom of the first cathode sheet;
[0016] The second battery cell includes a second anode sheet, a second separator, and a second cathode sheet. The second anode sheet, the second separator, the second cathode sheet, and the second separator are stacked and wound with each other to form the second battery cell. The fourth tab and the fifth tab extend from the top of the second anode sheet, and the sixth tab extends from the bottom of the second cathode sheet.
[0017] In a second aspect, the present application provides a square battery, including a square outer shell and a battery cell structure accommodated in the square outer shell, and the battery cell structure is the battery cell structure in any of the above embodiments.
[0018] In one embodiment, the square housing includes a housing body and a top cover, the top cover is welded to the housing body, the battery cell structure is accommodated in the housing body, a first pole and a second pole are provided on the top cover, the first tab is connected to the first pole, and the sixth tab is connected to the second pole.
[0019] In one embodiment, a plurality of the battery cell structures are accommodated in the housing body, and the plurality of battery cell structures are stacked.
[0020] For the above battery cell structure, by arranging the first battery cell and the second battery cell side by side, during the charging and discharging process, since the wound cores are arranged side by side, compared with the conventional method of stacking two battery cells, the placement method of the first battery cell and the second battery cell arranged side by side in this application reduces the absolute thickness of the wound core, so that when the battery is charged and discharged, the absolute value of the expansion of the electrode sheet is reduced, and the problem of electrode sheet expansion can be alleviated; on the other hand, because they are arranged side by side, the heat dissipation area of the battery is increased, making the temperature distribution from the inside to the outside of the battery relatively uniform, reducing the influence on the battery performance caused by uneven temperature rise, and the safety performance is also relatively good. Moreover, for the battery cell structure of this application, by providing a first tab, a second tab and a third tab on the first battery cell, and a third tab, a fourth tab and a fifth tab on the second battery cell, the second tab and the fourth tab are connected by a first connecting piece, the third tab and the sixth tab are connected by a second connecting piece, and the first battery cell and the second battery cell as a whole output electric power through the first tab and the fifth tab. In this way, it can be ensured that the two battery cells are connected in parallel, and the overall internal resistance of the battery cells can be reduced. And, only the tabs of one of the battery cells are used to output electric power, and the number of stacked tabs is relatively small, so it is not easy to have false soldering during the welding process. Moreover, adopting the battery cell structure of this application is suitable for making square batteries with a larger length and also suitable for making batteries with a relatively thin thickness, broadening the application scenarios. Description of the Drawings
[0021] Figure 1 It is a schematic structural diagram of the battery cell structure of an embodiment;
[0022] Figure 2 It is a schematic diagram of the electrode sheet structure of the first battery cell of the battery cell structure of an embodiment;
[0023] Figure 3 It is a schematic diagram of the electrode sheet structure of the second battery cell of the battery cell structure of an embodiment. Detailed Embodiments
[0024] To facilitate the understanding of the present application, in order to make the above-mentioned objects, features, and advantages of the present application more obvious and understandable, the following will describe the specific embodiments of the present application in detail with reference to the accompanying drawings. Many specific details are set forth in the following description to fully understand the present application, and the preferred embodiments of the present application are shown in the accompanying drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the disclosure of the present application more thorough and comprehensive. 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 departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present application, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined. In the description of the present application, "several" means at least one, such as one, two, etc., unless otherwise specifically defined. It should be noted that when an element is referred to as "fixed to" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present application belongs. The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.
[0025] In a first aspect, the present application provides a cell structure. Please refer to Figure 1, the battery cell structure includes a first battery cell 100 and a second battery cell 200, both the first battery cell 100 and the second battery cell 200 are square wound battery cells; the first battery cell 100 and the second battery cell 200 are arranged side by side; when placed in a square housing, they are placed in the square housing in a side-by-side arrangement to prevent the first battery cell and the second battery cell from stacking in the thickness direction. It can also be understood that the first battery cell and the second battery cell are placed along the width direction of the battery cell. The first battery cell 100 has a first tab 110 and a second tab 120 with opposite polarities extending from its top side, and the first battery cell 100 has a third tab 130 extending from its bottom side, and the first tab 110 and the third tab 130 have the same polarity; the second battery cell 200 has a fourth tab 210 and a fifth tab 220 with the same polarity extending from its top side, and the second battery cell 200 has a sixth tab 230 extending from its bottom side, and the fourth tab 210 and the sixth tab 230 have opposite polarities; and the third tab 130 and the sixth tab 230 have the same polarity; the second tab 120 and the fourth tab 210 are connected by a first connecting piece 300, the third tab 130 and the sixth tab 230 are connected by a second connecting piece 400, and the first battery cell 100 and the second battery cell 200 as a whole output power through the first tab 110 and the fifth tab 220.
[0026] The above battery cell structure is configured by arranging the first battery cell 100 and the second battery cell 200 side by side. During the charge and discharge process, since the two wound cores are placed side by side, compared with the traditional method of stacking two battery cells, the placement method of the first battery cell 100 and the second battery cell 200 placed side by side in this application reduces the absolute thickness of the wound core, so that when the battery is charged and discharged, the absolute value of the expansion of the electrode sheet decreases, and the problem of electrode sheet expansion can be alleviated. On the other hand, because they are placed side by side, the heat dissipation area of the battery is increased, making the temperature distribution from the inside to the outside of the battery relatively uniform, reducing the influence on the battery performance caused by uneven temperature rise, and the safety performance is also relatively good. Moreover, for the battery cell structure of this application, by providing a first tab 110, a second tab 120, and a third tab 130 on the first battery cell 100, and a third tab 210, a fourth tab 220, and a fifth tab 230 on the second battery cell 200, the second tab 120 and the fourth tab 210 are connected by a first connecting piece 300, the third tab 130 and the sixth tab 230 are connected by a second connecting piece 400, and the first battery cell 100 and the second battery cell 200 as a whole output power through the first tab 110 and the fifth tab 220. In this way, it can be ensured that the two battery cells are connected in parallel, and the overall internal resistance of the battery cells can be reduced. And, only the tabs of one of the battery cells are used to output power, and the number of stacked tabs is relatively small, so it is not easy to have false soldering during the welding process. Moreover, adopting the battery cell structure of this application is suitable for making square batteries with a larger length and also suitable for making batteries with a relatively thin thickness, broadening the application scenarios.
[0027] In one embodiment, after the second tab 120 and the fourth tab 210 are welded to the first connecting piece 300, they are folded and placed on the top side of the first battery cell 100 and the second battery cell 200; it can also be understood that the first connecting piece 300 welding the second tab and the fourth tab is placed flat on the top side of the overall battery cell structure by bending the tabs, so as to ensure saving the internal connection space. For example, after the third tab 130 and the sixth tab 230 are welded to the second connecting piece 400, they are folded and received on the bottom side of the first battery cell 100 and the second battery cell 200. This ensures saving the internal connection space.
[0028] In one embodiment, the second tab 120 is adjacent to the fourth tab 210, and the third tab 130 is adjacent to the sixth tab 230. In this way, it is ensured that the connection is relatively tight, which is beneficial to saving the internal space of the battery.
[0029] In one embodiment, at least one of the first tab 110, the second tab 120, the third tab 130, the fourth tab 210, the fifth tab 220, and the sixth tab 230 has the following structure: the width of the tab gradually decreases in the extending direction, and the tab has an arc-shaped corner structure, and the tab is a multi-tab structure. Among them, the fact that the width of the tab gradually decreases in the extending direction can be understood as that the tab has a trapezoidal structure. By setting the corner of the tab as an arc-shaped corner structure, the die-cut burrs can be reduced to improve the battery safety. By setting the tab as a multi-tab structure, the large-current charge and discharge capacity can be improved, and the internal resistance of the battery can also be reduced.
[0030] In one embodiment, the second tab 120 is welded to the first end of the first connecting piece 300, and the fourth tab 210 is welded to the second end of the first connecting piece 300; and / or, the third tab 130 is welded to the first end of the second connecting piece 400, and the sixth tab 230 is welded to the second end of the second connecting piece 400.
[0031] In one embodiment, the first tab 110 is a cathode tab, the second tab 120 is an anode tab, the first connecting piece 300 is a copper connecting piece, and the second connecting piece 400 is an aluminum connecting piece.
[0032] In one embodiment, please refer to Figure 2 , which is a schematic diagram of the first battery cell 100 formed by winding a composite electrode plate formed by separating a cathode plate 100a and an anode plate 100b of the first battery cell 100 by a separator. In this embodiment, the first battery cell 100 includes a first anode plate 100b, a first separator (not shown in the figure), and a first cathode plate 100a. The first anode plate 100b, the first separator, the first cathode plate 100a, and the first separator are stacked and wound with each other to form the first battery cell 100. The second tab 120 extends from the top of the first anode plate 100b, the first tab 110 extends from the top of the first cathode plate 100a, and the third tab 130 extends from the bottom of the first cathode plate 100a;
[0033] Please refer to Figure 3, which is a schematic diagram of the cathode sheet 200a and the anode sheet 200b of the second battery cell 200 being separated by a diaphragm to form a composite electrode sheet, and then the composite electrode sheet is wound to form the second battery cell. The second battery cell 200 includes a second anode sheet 200b, a second diaphragm (not shown) and a second cathode sheet 200a. The second anode sheet 200b, the second diaphragm, the second cathode sheet 200a and the second diaphragm are stacked and wound to form the second battery cell 200. The fourth pole tab 210 and the fifth pole tab 220 extend from the top of the second anode sheet 200b, and the sixth pole tab 230 extends from the bottom of the second cathode sheet 200a. In this way, the battery cell structure of this application can be formed better.
[0034] The above-mentioned battery cell structure is arranged side by side with the first battery cell and the second battery cell. During the charging and discharging process, because the winding core is placed side by side, compared with the traditional method of stacking two battery cells, the placement of the first battery cell and the second battery cell placed side by side in this application reduces the absolute thickness of the winding core, so that the absolute value of the expansion of the pole piece is reduced during the charging and discharging of the battery, which can alleviate the problem of pole piece expansion; on the other hand, because it is placed side by side, the heat dissipation area of the battery is increased, so that the temperature distribution from the inside to the outside of the battery is relatively uniform, reducing the impact of the battery performance caused by uneven temperature rise, and the safety performance is relatively good. Moreover, the battery cell structure of the present application is arranged on the first battery cell by arranging the first pole ear, the second pole ear and the third pole ear on the second battery cell, and the third pole ear, the fourth pole ear and the fifth pole ear on the second battery cell, the second pole ear and the fourth pole ear are connected by the first connecting piece, the third pole ear and the sixth pole ear are connected by the second connecting piece, and the first battery cell and the second battery cell as a whole output power through the first pole ear and the fifth pole ear, so that the two battery cells can be ensured to be arranged in parallel, and the overall internal resistance of the battery cell can be reduced. Moreover, power is outputted only through the tabs of one of the cells, and the number of tab stacking layers is relatively small, so it is not easy to have a cold weld during the welding process. Moreover, the cell structure of the present application is suitable for making longer square batteries and relatively thin batteries, which broadens the application scenarios.
[0035] In a second aspect, the present application provides a square battery, comprising a square casing and a cell structure accommodated in the square casing, wherein the cell structure is the cell structure as described in any of the above embodiments.
[0036] In one embodiment, the square shell includes a shell and a top cover, the top cover is welded to the top cover, the battery cell structure is accommodated in the shell, a first pole and a second pole are arranged on the top cover, the first pole ear is connected to the first pole, and the sixth pole ear is connected to the second pole.
[0037] In one embodiment, a plurality of the battery cell structures are disposed inside the housing, and the plurality of battery cell structures are stacked. That is to say, in this embodiment, a plurality of battery cell structures can also be provided. The plurality of battery cell structures each include a first battery cell and a second battery cell arranged side by side. The first battery cells of the plurality of battery cell structures are arranged in sequence, and a battery with a relatively large thickness can also be formed. In this way, a plurality of small battery cells with a standard thickness can be provided, and then the plurality of battery cells are combined, reducing the winding difficulty of each small battery cell, and the winding process is relatively simple.
[0038] For the above-mentioned battery cell structure, by arranging the first battery cell and the second battery cell side by side, during the charging and discharging process, since the winding cores are placed side by side, compared with the conventional method of stacking two battery cells, the placement method of the first battery cell and the second battery cell placed side by side in the present application reduces the absolute thickness of the winding core, so that when the battery is charged and discharged, the absolute value of the expansion of the electrode sheet is reduced, and the problem of electrode sheet expansion can be alleviated; on the other hand, because they are placed side by side, the heat dissipation area of the battery is increased, making the temperature distribution from the inside to the outside of the battery relatively uniform, reducing the influence on the battery performance caused by uneven temperature rise, and the safety performance is also relatively good. Moreover, for the battery cell structure of the present application, by providing a first tab, a second tab, and a third tab on the first battery cell, and a third tab, a fourth tab, and a fifth tab on the second battery cell, the second tab and the fourth tab are connected by a first connecting piece, the third tab and the sixth tab are connected by a second connecting piece, and the first battery cell and the second battery cell as a whole output power through the first tab and the fifth tab. In this way, it can be ensured that the two battery cells are connected in parallel, and the overall internal resistance of the battery cells can be reduced. And only by outputting power through the tabs of one of the battery cells, the number of stacked tab layers is relatively small, and it is not easy to have false soldering during the welding process. Moreover, adopting the battery cell structure of the present application is suitable for making square batteries with a larger length and is also suitable for making batteries with a relatively small thickness, broadening the application scenarios.
[0039] It should be noted that in the traditional battery cell structure, usually two or even four stacked battery cells are provided to reduce the internal resistance of the battery. When using stacked battery cells, during the charging and discharging process, the electrode sheets expand. The thicker the thickness, the larger the absolute value of the expansion. At the same time, the stacked winding cores affect heat dissipation, making the temperature of the winding cores uneven from the inside to the outside, thereby affecting the performance of the battery. While adopting the battery cell structure of the present application, during the charging and discharging process, since the winding cores are placed side by side, compared with the traditional stacked winding core structure, the absolute thickness of the winding core is reduced, so that when the battery is charged and discharged, the absolute value of the expansion of the electrode sheet is reduced; on the other hand, because they are placed side by side, the heat dissipation area of the battery is increased, making the temperature distribution from the inside to the outside of the battery relatively uniform, reducing the influence on the battery performance caused by uneven temperature rise.
[0040] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the various technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as falling within the scope described in this specification. It should be noted that the phrases "in one embodiment of the present application", "for example", "again, for example", etc. are intended to illustrate the present application, rather than to limit the present application. The above-described embodiments only represent several implementation manners of the present application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.
Claims
1. A battery cell structure, characterized in that: It comprises a first battery cell and a second battery cell, wherein the first battery cell and the second battery cell are both square wound battery cells; the first battery cell and the second battery cell are arranged side by side; The first battery cell has a first pole lug and a second pole lug with opposite polarities extending from the top end thereof, and a third pole lug extending from the bottom end thereof, wherein the first pole lug and the third pole lug have the same polarity; The second battery cell has a fourth pole tab and a fifth pole tab with the same polarity extending from the top end thereof, and a sixth pole tab extending from the bottom end thereof, wherein the fourth pole tab and the sixth pole tab have opposite polarities; and the third pole tab and the sixth pole tab have the same polarity; The second pole tab and the fourth pole tab are connected via a first connecting sheet, the third pole tab and the sixth pole tab are connected via a second connecting sheet, and the first battery cell and the second battery cell as a whole output power via the first pole tab and the fifth pole tab.
2. The battery cell structure according to claim 1, characterized in that: The second electrode tab and the fourth electrode tab are welded to the first connecting sheet and then folded and placed on the top side of the first battery cell and the second battery cell; The third electrode tab and the sixth electrode tab are welded to the second connecting sheet and then folded and accommodated in the bottom ends of the first battery cell and the second battery cell.
3. The battery cell structure according to claim 1, characterized in that: The second pole tab is adjacent to the fourth pole tab, and the third pole tab is adjacent to the sixth pole tab.
4. The battery cell structure according to claim 3, characterized in that: At least one of the first pole lug, the second pole lug, the third pole lug, the fourth pole lug, the fifth pole lug, and the sixth pole lug has the following structure: the width of the pole lug gradually decreases from the extending direction, and the pole lug has an arc-shaped corner structure, and the pole lug is a multi-pole lug structure.
5. The battery cell structure according to claim 3, characterized in that: The second electrode tab is welded to the first end of the first connecting piece, and the fourth electrode tab is welded to the second end of the first connecting piece; And / or, the third electrode tab is welded to the first end of the second connecting piece, and the sixth electrode tab is welded to the second end of the second connecting piece.
6. The battery cell structure according to claim 5, characterized in that: The first electrode tab is a cathode tab, the second electrode tab is an anode tab, the first connecting piece is a copper connecting piece, and the second connecting piece is an aluminum connecting piece.
7. The battery cell structure according to claim 6, characterized in that: The first battery cell comprises a first anode sheet, a first separator and a first cathode sheet, wherein the first anode sheet, the first separator, the first cathode sheet and the first separator are stacked and wound to form the first battery cell, the first anode sheet has the second pole tab extending from the top end, the first cathode sheet has the first pole tab extending from the top end, and the first cathode sheet has the third pole tab extending from the bottom end; The second battery cell includes a second anode sheet, a second separator and a second cathode sheet. The second anode sheet, the second separator, the second cathode sheet and the second separator are stacked and wound together to form the second battery cell. The second anode sheet has the fourth pole tab and the fifth pole tab extending from the top end, and the second cathode sheet has the sixth pole tab extending from the bottom end.
8. A square battery, characterized in that: The invention comprises a square shell and a battery cell structure accommodated in the square shell, wherein the battery cell structure is the battery cell structure as claimed in any one of claims 1 to 7.
9. The square battery according to claim 8, characterized in that: The square shell includes a shell and a top cover, the top cover is welded to the top cover, the battery cell structure is accommodated in the shell, a first pole and a second pole are arranged on the top cover, the first pole ear is connected to the first pole, and the sixth pole ear is connected to the second pole.
10. The square battery according to claim 9, characterized in that: The shell contains a plurality of the battery core structures, and the plurality of the battery core structures are stacked.