Battery cell and battery pack

Abstract

The utility model discloses a battery cell and a battery pack. The battery cell comprises a plurality of pole pieces, a first tab, a second tab and an isolating membrane, the plurality of pole pieces are stacked along a first direction, an isolating membrane is arranged between every two adjacent pole pieces, the two pole pieces positioned on the outermost side along the first direction are end pole pieces, the first pole lug is electrically connected with one end pole piece, and the second pole lug is electrically connected with the other end pole piece. Therefore, not only is the complex procedure of independently welding a tab on each pole piece in the traditional scheme omitted, but also the assembly steps of the tabs are greatly reduced, the production process is simplified, the process control difficulty caused by the alignment deviation of the multiple tabs is reduced, and the production efficiency and the product consistency are favorably improved. Besides, the number of the tabs is reduced, so that the superimposed effect of contact resistance when multiple tabs are connected in parallel traditionally can be avoided, a current transmission path is more centralized and unified, the large-current charging and discharging performance is improved, and the problem that the over-current capacity is limited due to too high resistance in a traditional scheme is solved.

Description

Technical Field

[0001] This application belongs to the field of battery technology, specifically relating to a battery cell and a battery pack. Background Technology

[0002] The lifespan and driving range of car batteries are critical technical indicators for electric vehicles and are also the primary factors consumers consider when purchasing a car. Improving the cycle life and cost of battery packs is the research focus of most battery manufacturers.

[0003] A battery pack includes battery cells. The electrode assembly within a battery cell is formed by winding or stacking positive and negative electrode plates and a separator. Each electrode plate has a tab. The tabs of all positive electrode plates are integrated together to form a first tab cluster, and the tabs of all negative electrode plates are integrated together to form a second tab cluster. However, in related technologies, each electrode plate needs to be connected to a tab, which complicates the process. Furthermore, having a large number of tabs increases the internal resistance of the battery cell and reduces its overcurrent capacity. Utility Model Content

[0004] This application aims to provide a battery cell and battery pack that can solve the problems of complex manufacturing process and low overcurrent capacity of the battery cell in the prior art.

[0005] To solve the above-mentioned technical problems, this application is implemented as follows:

[0006] In a first aspect, embodiments of this application propose a battery cell, comprising: a plurality of electrode sheets, a first electrode tab, a second electrode tab, and a separator; the plurality of electrode sheets are stacked along a first direction, the separator is provided between two adjacent electrode sheets, the two outermost electrode sheets along the first direction are end electrode sheets, the first electrode tab is electrically connected to one of the end electrode sheets, and the second electrode tab is electrically connected to the other end electrode sheet.

[0007] Optionally, among the plurality of electrodes, the electrodes other than the end electrodes are intermediate electrodes, and the intermediate electrodes are provided with active material layers on both sides along the first direction, and the polarities of the active material layers on both sides of the intermediate electrodes are opposite.

[0008] Optionally, the intermediate electrode is provided with multiple layers; the active material layers of the multiple intermediate electrodes facing the same side have the same polarity.

[0009] Optionally, the side of the end electrode facing the adjacent electrode is designated as the first side, and the first side of the end electrode is provided with an active material layer, wherein the polarities of the active material layers provided on the first sides of the two end electrodes are opposite.

[0010] Optionally, it also includes a solid electrolyte; the solid electrolyte is disposed in the space between each pair of adjacent electrodes, excluding the separator membrane.

[0011] Optionally, it also includes a protective film; a plurality of the electrodes are stacked to form an electrode group, the protective film covers at least a portion of the circumferential outer side of the electrode group, and each pair of adjacent electrodes and the protective film enclose a receiving cavity, the solid electrolyte being disposed in the receiving cavity.

[0012] Optionally, the protective film at least partially covers the connection between the first tab and one of the end electrodes; and / or, the protective film at least partially covers the connection between the second tab and the other end electrode.

[0013] Optionally, the electrode includes a current collector, and at least one side of the current collector is provided with an active material layer, and the current collectors in the plurality of electrodes are made of the same material.

[0014] Optionally, the current collector includes at least one of aluminum foil, titanium-based composite current collector, and carbon-based composite current collector; and / or, the current collector has a porous structure.

[0015] Secondly, embodiments of this application provide a battery pack including the battery cells described in the above embodiments.

[0016] In the embodiments of this application, multiple electrodes are stacked along a first direction, with an isolation film between adjacent electrodes. The two outermost electrodes along the first direction are end electrodes. A first tab is electrically connected to one of the end electrodes, and a second tab is electrically connected to the other end electrode. This not only eliminates the complex process of welding tabs to each electrode individually in traditional solutions, significantly reducing the assembly steps of the tabs, but also simplifies the production process and reduces the difficulty of process control caused by misalignment of multiple tabs, thus helping to improve production efficiency and product consistency. In addition, reducing the number of tabs avoids the superposition effect of contact resistance when multiple tabs are connected in parallel in traditional solutions, making the current transmission path more concentrated and unified, thereby reducing the overall internal resistance of the cell, improving high-current charging and discharging performance, and alleviating the problem of limited overcurrent capacity caused by excessive resistance in traditional solutions.

[0017] 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

[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0019] Figure 1 This is a schematic diagram of a first type of battery cell according to an embodiment of this application;

[0020] Figure 2 This is a schematic diagram of a second type of battery cell according to an embodiment of this application.

[0021] Figure label:

[0022] 1-End electrode; 2-Intermediate electrode; 3-First tab; 4-Second tab; 5-Separating membrane; 6-Positive electrode active material layer; 7-Negative electrode active material layer; 8-First side; 9-Second side; 10-Protective membrane; 11-Current collector; X-First direction. Detailed Implementation

[0023] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated 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 are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0024] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise stated, "multiple" means two or more. Furthermore, "and / or" in the specification and claims indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0025] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, 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.

[0026] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0027] The battery cells and battery packs provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0028] like Figure 1 and Figure 2 As shown in the embodiment of this application, a battery cell is proposed, including: multiple electrode sheets, a first electrode tab 3, a second electrode tab 4, and a separator 5; the multiple electrode sheets are stacked along a first direction X, and a separator 5 is provided between two adjacent electrode sheets; the two outermost electrode sheets along the first direction X are end electrode sheets 1; the first electrode tab 3 is electrically connected to one of the end electrode sheets 1, and the second electrode tab 4 is electrically connected to the other end electrode sheet 1.

[0029] In the embodiments of this application, multiple electrodes are stacked along a first direction X, with an isolation membrane 5 between adjacent electrodes. The two outermost electrodes along the first direction X are end electrodes 1. A first tab 3 is electrically connected to one of the end electrodes 1, and a second tab 4 is electrically connected to the other end electrode 1. This not only eliminates the complex process of welding tabs to each electrode individually in traditional solutions, significantly reducing the assembly steps of the tabs, but also simplifies the production process and reduces the difficulty of process control caused by misalignment of multiple tabs, thus helping to improve production efficiency and product consistency. In addition, reducing the number of tabs can avoid the superposition effect of contact resistance when multiple tabs are connected in parallel in traditional solutions, making the current transmission path more concentrated and unified, thereby reducing the overall internal resistance of the cell, improving the high-current charging and discharging performance, and alleviating the problem of limited overcurrent capacity caused by excessive resistance in traditional solutions.

[0030] Furthermore, by electrically connecting the first tab 3 to one of the end plates 1 and the second tab 4 to the other end plate 1, the redundant tab structure of the intermediate plate 2 can be eliminated to free up more effective space, thereby increasing the proportion of the active material layer inside the cell and improving the energy density of the cell.

[0031] In some embodiments, such as Figure 1 As shown, along the first direction X, the uppermost end electrode 1 is the positive electrode, and the first tab 3 is the positive tab, connected to the positive electrode; the lowermost end electrode 1 is the negative electrode, and the second tab 4 is the negative tab, connected to the negative electrode. Alternatively, along the first direction X, the uppermost end electrode 1 is the negative electrode, and the first tab 3 is the negative tab, connected to the negative electrode; the lowermost end electrode 1 is the positive electrode, and the second tab 4 is the positive tab, connected to the positive electrode. Those skilled in the art can choose according to actual needs, and this embodiment does not impose limitations.

[0032] In some embodiments, such as Figure 1As shown, the first electrode tab 3 can be positioned directly above the uppermost end electrode 1, and the second electrode tab 4 can be positioned directly above the lowermost end electrode 1. Alternatively, the first electrode tab 3 can be positioned on the side of the uppermost end electrode 1, and the second electrode tab 4 can be positioned on the side of the lowermost end electrode 1. Those skilled in the art can choose according to actual needs, and this embodiment does not impose any limitations.

[0033] Optionally, such as Figure 1 and Figure 2 As shown, among the multiple electrodes, the electrodes other than the end electrodes 1 are intermediate electrodes 2. The intermediate electrodes 2 are provided with active material layers on both sides along the first direction X, and the polarities of the active material layers on both sides of the intermediate electrodes 2 are opposite.

[0034] In this embodiment, an active material layer is provided on both sides of the intermediate electrode 2 along the first direction X, and the polarities of the active material layers on both sides of the intermediate electrode 2 are opposite. In this way, the opposite polarity active layers on both sides of the intermediate electrode 2 enable a single electrode to have both positive and negative electrode functions, forming an integrated structure similar to a bipolar electrode. This simplifies the complex arrangement of alternating positive and negative electrode layers in traditional battery cells, reduces the total number of electrode layers, and improves space utilization.

[0035] In some embodiments, such as Figure 1 As shown, a positive electrode active material layer 6 is provided on one side surface of the intermediate electrode 2 along the first direction X, and a negative electrode active material layer 7 is provided on the other side surface of the intermediate electrode 2 along the first direction X. In this way, the opposite expansion / contraction characteristics on both sides of the intermediate electrode 2 can partially offset the mechanical stress generated by volume changes, reducing the risk of structural deformation during cell cycling.

[0036] Specifically, such as Figure 1 As shown in the diagram, taking the first intermediate electrode 2 as an example (viewed from top to bottom), during charging, metal ions escape from the positive active material layer 6 of the first intermediate electrode 2 and embed into the negative active material layer 7 of the opposite intermediate electrode 2. This causes the positive active material layer 6 of the first intermediate electrode 2 to shrink due to the loss of metal ions. Meanwhile, the negative active material layer 7 of the first intermediate electrode 2 receives the metal ions that escape from the positive active material layer 6 of the end electrode 1, causing the negative active material layer 7 of the first intermediate electrode 2 to expand due to the acceptance of metal ions. In this way, one side of the surface of the first intermediate electrode 2 shrinks while the other side expands, maintaining a dynamic balance and reducing the risk of structural deformation during cell cycling. Of course, the principle of discharging is similar to that of charging, and will not be elaborated upon in this embodiment.

[0037] Optionally, such as Figure 1 and Figure 2As shown, there are multiple intermediate electrodes 2; the polarity of the active material layers of the multiple intermediate electrodes 2 facing the same side is the same.

[0038] In this embodiment, multiple intermediate electrodes 2 are provided, and the active material layers facing the same side of the multiple intermediate electrodes 2 have the same polarity. In this way, the intermediate electrodes 2 with the same polarity on one side form a layered, unidirectional charge transport channel, and the current is transmitted step-by-step along a fixed direction between the layers, reducing the path detours in traditional cross-lamination and improving the overall electron conduction efficiency. Furthermore, the design of having the same polarity on the same side allows for batch coating of active materials of the same polarity, thereby reducing the frequency of changing coating formulations on the production line and increasing production cycle time.

[0039] In some embodiments, such as Figure 1 As shown, from top to bottom, the uppermost end electrode 1 is the positive electrode, and the lowermost end electrode 1 is the negative electrode. Multiple intermediate electrodes 2 have a negative electrode active material layer 7 on the side facing the positive electrode and a positive electrode active material layer 6 on the side facing the negative electrode. Of course, this can also be done when the uppermost end electrode 1 is the negative electrode, the lowermost end electrode 1 is the positive electrode, and the multiple intermediate electrodes 2 have a negative electrode active material layer 7 on the side facing the positive electrode and a positive electrode active material layer 6 on the side facing the negative electrode. Those skilled in the art can choose according to actual needs, and this embodiment does not impose any limitations.

[0040] It should be noted that the intermediate electrode 2 can be set to three, four, five, or other quantities. Those skilled in the art can choose according to actual needs, and this application embodiment does not impose any restrictions.

[0041] Optionally, such as Figure 1 and Figure 2 As shown, the side of the end electrode 1 facing the adjacent electrode is the first side 8. The first side 8 of the end electrode 1 is provided with an active material layer, and the polarity of the active material layers provided on the first side 8 of the two end electrodes 1 is opposite.

[0042] In this embodiment, the side of the end electrode 1 facing the adjacent electrode is designated as the first side 8. The first side 8 of the end electrode 1 is provided with an active material layer, and the polarities of the active material layers on the first side 8 of the two end electrodes 1 are opposite. In this way, the opposite polarity active layers of the two end electrodes 1 are coupled with the same-side polarity structure of the middle electrode 2 to form a complete current loop that is closed from start to finish. This eliminates the redundant current collector 11 transition path in traditional cells and improves charge transfer efficiency.

[0043] In some embodiments, such as Figure 2As shown, the uppermost end electrode 1 also includes a second side 9 disposed opposite to the first side 8. If the first side 8 is provided with a positive electrode active material layer 6, then the second side 9 is provided with a negative electrode active material layer 7. In this way, the end electrode 1 and the intermediate electrode 2 have the same structure, eliminating the need for separate production of the end electrode 1, thereby reducing production costs. Of course, as... Figure 1 As shown, the second side 9 of the uppermost end electrode 1 may not have an active material layer. Those skilled in the art can choose according to actual needs, and this application embodiment does not limit this.

[0044] In some embodiments, such as Figure 1 As shown, from top to bottom, the uppermost end electrode 1 is the positive electrode, and the lowermost end electrode 1 is the negative electrode; of course, the uppermost end electrode 1 can also be the negative electrode, and the lowermost end electrode 1 can be the positive electrode; those skilled in the art can choose according to actual needs, and the embodiments of this application are not limited here.

[0045] Optionally, such as Figure 1 and Figure 2 As shown, it also includes a solid electrolyte; the solid electrolyte is disposed in the space between each pair of adjacent electrodes, excluding the separator 5.

[0046] In this embodiment, the solid electrolyte is disposed in the space between each pair of adjacent electrodes, excluding the separator 5. This creates a continuous permeation structure between the electrodes, which, together with the pores of the separator 5, constructs a multi-level ion transport path, achieving a balance between fast-charging performance and cycle stability. Furthermore, a stable solid-solid interface is formed between the solid electrolyte and the active material layer of the electrodes, reducing decomposition side reactions of traditional liquid electrolytes on the electrode surface and improving interfacial ion migration efficiency.

[0047] In some embodiments, the solid electrolyte can be a polymer solid electrolyte, which is composed of a polymer matrix and a lithium salt (such as LiClO4, LiAsF4, LiPF6, LiBF4, etc.); of course, the solid electrolyte can be an oxide crystalline solid electrolyte, which has high chemical stability and can exist stably in the atmospheric environment.

[0048] Of course, the solid electrolyte can be a lithium-containing solid electrolyte or a sodium-containing solid electrolyte. Those skilled in the art can choose according to actual needs, and the embodiments of this application are not limited here.

[0049] Optionally, such as Figure 1 and Figure 2As shown, it also includes a protective film 10; multiple electrodes are stacked to form an electrode group, the protective film 10 covers at least part of the circumferential outer side of the electrode group, and each pair of adjacent electrodes and the protective film 10 enclose a cavity to form a receiving cavity, in which a solid electrolyte is disposed.

[0050] In this embodiment, multiple electrodes are stacked to form an electrode group. A protective film 10 covers at least a portion of the circumferential outer side of the electrode group. Each pair of adjacent electrodes and the protective film 10 enclose a cavity, in which a solid electrolyte is disposed. This allows the protective film 10 to cover the electrode group from the circumferential outer side, forming a physical barrier layer that isolates it from external environmental factors such as moisture and oxygen, while preventing leakage of internal electrolyte components, thus achieving comprehensive encapsulation and protection of the battery cell. Furthermore, the flexible nature of the protective film 10 can absorb the expansion stress of the electrode group, and the elastic deformation buffers the volume change impact during cycling, reducing mechanical fatigue damage.

[0051] In some embodiments, the protective film 10 can be a nanofilm, which refers to a film composed of particles (crystals) with a size on the nanometer scale or a single-layer or multi-layer film with a thickness on the nanometer scale.

[0052] Optionally, such as Figure 1 and Figure 2 As shown, the protective film 10 at least partially covers the connection between the first tab 3 and one of the end tabs 1.

[0053] In this embodiment, a protective film 10 is provided to at least partially cover the connection between the first tab 3 and one of the end electrode pieces 1. This allows the protective film 10 to partially cover the connection between the first tab 3 and one of the end electrode pieces 1, forming a flexible buffer layer to absorb external vibrations, bending, and other mechanical impacts, reducing the risk of weld breakage and improving structural reliability under extreme conditions. Furthermore, by sealing the connection interface between the first tab 3 and one of the end electrode pieces 1, moisture, oxygen, and electrolyte vapors are isolated from the metal welding area, preventing oxidation-induced increases in contact resistance.

[0054] Optionally, such as Figure 1 and Figure 2 As shown, the protective film 10 at least partially covers the connection between the second electrode tab 4 and the other end electrode 1 therein.

[0055] In this embodiment, a protective film 10 is provided to at least partially cover the connection between the second tab 4 and the other end electrode 1. This allows the protective film 10 to partially cover the connection between the second tab 4 and the other end electrode 1, forming a flexible buffer layer to absorb external vibrations, bending, and other mechanical impacts, reducing the risk of weld breakage and improving structural reliability under extreme conditions. Furthermore, by sealing the connection interface between the second tab 4 and the other end electrode 1, moisture, oxygen, and electrolyte vapor are isolated from the metal welding area, preventing oxidation-induced increases in contact resistance.

[0056] Optionally, such as Figure 1 and Figure 2 As shown, the electrode includes a current collector 11, and an active material layer is provided on at least one side of the current collector 11. The current collectors 11 in the plurality of electrodes are made of the same material.

[0057] In this embodiment, by providing an active material layer on at least one side of the current collector 11, the current collectors 11 in multiple electrodes are made of the same material. This uniform material eliminates the costs of separate procurement, storage, and switching of positive and negative current collectors 11, reducing material management complexity. Furthermore, the surface treatment process for current collectors 11 of the same material can be consistent, avoiding parameter adjustments caused by material differences in traditional positive and negative current collectors 11 during coating production lines, thus improving production cycle time.

[0058] Optionally, such as Figure 1 and Figure 2 As shown, the current collector 11 includes at least one of aluminum foil, titanium-based composite current collector 11, and carbon-based composite current collector 11.

[0059] In this embodiment, the current collector 11 is configured to be at least one of aluminum foil, titanium-based composite current collector 11, and carbon-based composite current collector 11. This allows for the formation of a gradient material library of the three types of current collectors 11: aluminum foil (low cost), titanium-based (high strength and corrosion resistance), and carbon-based (lightweight). This enables flexible selection for different application scenarios (such as consumer electronics, power batteries, and aerospace) to balance performance and cost requirements.

[0060] Current battery manufacturing processes involve a negative electrode consisting of copper foil and a negative active material coated on both sides of the copper foil, and a positive electrode consisting of aluminum foil and a uniform positive active material coated on the aluminum foil. The positive and negative electrode sheets are then wound or stacked to form a battery cell. However, because copper has a density of 8.9 g / cm³ and aluminum a density of 2.7 g / cm³, the density of copper foil is greater than that of aluminum foil, limiting the improvement of the battery cell's energy density.

[0061] For example, the current collector 11 is made of aluminum foil and the electrolyte is a sodium-containing solid electrolyte. Since sodium ions do not form an alloy with aluminum, the negative electrode sheet can use an aluminum-containing current collector 11. In this way, the weight of the cell can be further reduced and the energy density of the battery can be improved.

[0062] It should be noted that the positive electrode active material layer 6 can be an iron-manganese-nickel base layer, and the negative electrode active material layer 7 is a hard carbon layer. Of course, the positive electrode active material layer 6 and the negative electrode active material layer 7 can also be other material layers. Those skilled in the art can choose according to actual needs, and the embodiments of this application are not limited here.

[0063] Optionally, the current collector 11 has a porous structure.

[0064] In this embodiment, the current collector 11 is configured with a porous structure. This porous structure allows the active material to be embedded in the pore walls of the current collector 11, achieving microscopic mechanical interlocking, significantly increasing the effective contact area between the active layer and the current collector 11, and reducing interfacial contact resistance. Furthermore, the porous space provides a buffer region for the volume expansion of the active material during charging and discharging, suppressing interlayer stress accumulation and reducing the risk of electrode pulverization. Additionally, the porous structure can serve as a capillary permeation channel for the solid electrolyte precursor, promoting its uniform distribution between electrodes and avoiding localized filling defects.

[0065] Secondly, embodiments of this application provide a battery pack, including the battery cells as described in the above embodiments.

[0066] In the embodiments of this application, multiple electrodes are stacked along a first direction X, with an isolation membrane 5 between adjacent electrodes. The two outermost electrodes along the first direction X are end electrodes 1. A first tab 3 is electrically connected to one of the end electrodes 1, and a second tab 4 is electrically connected to the other end electrode 1. This not only eliminates the complex process of welding tabs to each electrode individually in traditional solutions, significantly reducing the assembly steps of the tabs, but also simplifies the production process and reduces the difficulty of process control caused by misalignment of multiple tabs, thus helping to improve production efficiency and product consistency. In addition, reducing the number of tabs can avoid the superposition effect of contact resistance when multiple tabs are connected in parallel in traditional solutions, making the current transmission path more concentrated and unified, thereby reducing the overall internal resistance of the cell, improving the high-current charging and discharging performance, and alleviating the problem of limited overcurrent capacity caused by excessive resistance in traditional solutions.

[0067] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "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.

[0068] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery cell, characterized in that, include: Multiple electrodes, a first electrode tab (3), a second electrode tab (4), and a separator (5); Multiple electrodes are stacked along a first direction (X), and a separator (5) is provided between two adjacent electrodes. The two outermost electrodes along the first direction (X) are end electrodes (1). The first tab (3) is electrically connected to one of the end electrodes (1), and the second tab (4) is electrically connected to the other end electrode (1).

2. The battery cell according to claim 1, characterized in that, Among the plurality of electrodes, the electrodes other than the end electrodes (1) are intermediate electrodes (2). The intermediate electrodes (2) are provided with active material layers on both sides along the first direction (X), and the polarities of the active material layers on both sides of the intermediate electrodes (2) are opposite.

3. The battery cell according to claim 2, characterized in that, The intermediate electrode (2) is provided in multiple ways; the polarity of the active material layer facing the same side of the multiple intermediate electrode (2) is the same.

4. The battery cell according to claim 1, characterized in that, The side of the end electrode (1) facing the adjacent electrode is the first side (8). The first side (8) of the end electrode (1) is provided with an active material layer. The polarities of the active material layers provided on the first sides (8) of the two end electrodes (1) are opposite.

5. The battery cell according to claim 1, characterized in that, It also includes a solid electrolyte; the solid electrolyte is disposed in the space between each two adjacent electrodes, excluding the separator (5).

6. The battery cell according to claim 5, characterized in that, It also includes a protective film (10); Multiple electrodes are stacked to form an electrode group. The protective film (10) covers at least a portion of the outer circumferential area of ​​the electrode group. Each pair of adjacent electrodes and the protective film (10) enclose a cavity to form a receiving cavity. The solid electrolyte is disposed in the receiving cavity.

7. The battery cell according to claim 6, characterized in that, The protective film (10) at least partially covers the connection between the first tab (3) and one of the end plates (1); and / or, the protective film (10) at least partially covers the connection between the second tab (4) and the other end plate (1).

8. The battery cell according to any one of claims 1-7, characterized in that, The electrode includes a current collector (11), and at least one side of the current collector (11) is provided with an active material layer. The current collectors (11) in the plurality of electrodes are made of the same material.

9. The battery cell according to claim 8, characterized in that, The current collector (11) includes at least one of aluminum foil, titanium-based composite current collector (11), and carbon-based composite current collector (11); and / or, the current collector (11) has a porous structure.

10. A battery pack, characterized in that, Includes the battery cell as described in any one of claims 1-9 above.

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