CN116914381A

CN116914381A - Battery monomer, battery and power consumption device

Info

Publication number: CN116914381A
Application number: CN202311186307.0A
Authority: CN
Inventors: 许虎; 黄思应
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2023-09-14
Filing date: 2023-09-14
Publication date: 2023-10-20

Abstract

The application discloses a battery monomer, a battery and an electricity utilization device. The battery cell includes a case, an electrode terminal, and an electrode assembly. The housing has a first wall. The electrode terminal is arranged on the first wall in an insulating manner. The electrode assembly is accommodated in the shell and comprises a main body part, a first tab and a second tab, the polarities of the first tab and the second tab are opposite, the first tab and the second tab are arranged at one end, close to the first wall, of the main body part, the first tab is electrically connected with the electrode terminal, and the second tab is electrically connected with the first wall. The central axis of the electrode terminal is deviated from the central axis of the battery cell, and the orthographic projection of the electrode terminal falls into the orthographic projection of the first tab along the thickness direction of the first wall. The technical scheme provided by the application can improve the reliability of the battery.

Description

Battery monomer, battery and power consumption device

Technical Field

The application relates to the technical field of batteries, in particular to a battery cell, a battery and an electric device.

Background

Energy conservation and emission reduction are key to sustainable development of the automobile industry, and electric vehicles become an important component of sustainable development of the automobile industry due to the energy conservation and environmental protection advantages of the electric vehicles. For electric vehicles, battery technology is an important factor in the development of the electric vehicles.

In the development of battery technology, how to improve the reliability of a battery is a technical problem to be solved in battery technology.

Disclosure of Invention

The application provides a battery monomer, a battery and an electricity utilization device.

The application is realized by the following technical scheme:

in a first aspect, the present application provides a battery cell including a case, an electrode terminal, and an electrode assembly. The housing has a first wall. The electrode terminal is arranged on the first wall in an insulating manner. The electrode assembly is accommodated in the shell and comprises a main body part, a first tab and a second tab, the polarities of the first tab and the second tab are opposite, the first tab and the second tab are arranged at one end, close to the first wall, of the main body part, the first tab is electrically connected with the electrode terminal, and the second tab is electrically connected with the first wall. The central axis of the electrode terminal deviates from the central axis of the battery cell, and the orthographic projection of the electrode terminal and the orthographic projection of the first tab fall into the orthographic projection of the first tab along the thickness direction of the first wall.

In the above technical scheme, the first tab and the second tab of the electrode assembly are both arranged on the same end face of the main body, which is favorable for saving the space occupied by the electrode assembly in the direction from the electrode assembly to the first wall, so as to improve the energy density of the battery cell with the electrode assembly. The electrode terminal is eccentrically arranged on the central axis of the battery cell, and the orthographic projection of the electrode terminal is arranged to fall into the orthographic projection of the first tab along the thickness direction of the first wall, so that compared with the scheme that the electrode terminal is arranged on the battery cell in the middle, on the one hand, the electrode terminal (or the position where the electrode terminal is electrically connected with the first tab) is far away from the second tab (or the position where the second tab is electrically connected with the first wall), and therefore, the overlapping of the positive electrode and the negative electrode of the battery cell can be reduced, and the risk of internal short circuit of the battery cell is caused; on the other hand, the current transmission path between the electrode terminal and the first tab can be reduced, so that the current output or input capacity of the battery cell can be improved, and the battery has higher reliability.

According to some embodiments of the application, the electrode assembly is a rolled electrode assembly, and the body portion has a central through hole penetrating the body portion in an axial direction of the body portion. The orthographic projection of the electrode terminal does not overlap with the center through hole in the thickness direction of the first wall.

Compared with the prior battery cell, the electrode terminal and the first tab are electrically connected in the position corresponding to the central through hole, in the technical scheme, the orthographic projection of the electrode terminal is arranged to be non-overlapped with the central through hole along the thickness direction of the first wall, so that the position where the electrode terminal and the first tab are electrically connected is far away from the central through hole, the electrode terminal (or the position where the electrode terminal and the first tab are electrically connected) and the second tab (or the position where the second tab and the first wall are electrically connected) are far away from each other as far as possible, the risk that the battery cell is internally short-circuited due to the overlapping of the anode and the cathode of the battery cell can be reduced, and the battery has higher reliability.

According to some embodiments of the application, the first wall is provided with a liquid filling hole, which is at least partially opposite to the central through hole in the thickness direction of the first wall.

In the technical scheme, the electrode terminal is eccentrically arranged on the first wall, so that the liquid injection hole can be arranged in the center of the first wall and is opposite to at least part of the center through hole, on one hand, the injection efficiency of electrolyte can be improved, and the manufacturing efficiency of the battery cell is improved; on the other hand, the electrolyte can infiltrate the electrode assembly through the hole wall of the central through hole, so that the electrolyte has higher infiltration rate, and the improvement of the battery performance is facilitated.

According to some embodiments of the application, the central axis of the liquid injection hole coincides with the central axis of the battery cell.

In the technical scheme, the central axis of the liquid injection hole is overlapped with the central axis of the battery monomer, so that on one hand, the electrolyte can be rapidly injected into the shell through the liquid injection hole, and the manufacturing efficiency of the battery monomer is improved; on the other hand, the electrolyte can infiltrate the electrode assembly through the hole wall of the central through hole, so that the electrolyte has higher infiltration rate, and the improvement of the battery performance is facilitated.

According to some embodiments of the application, the distance from the central axis of the electrode terminal to the central axis of the battery cell is h; along the direction orthogonal to the central axis of the battery cell, the maximum distance from the edge of the first wall to the central axis of the battery cell is r, and r/5 is less than or equal to h and less than r.

In the above technical scheme, the distance from the central axis of the electrode terminal to the central axis of the battery cell is h, the maximum distance from the edge of the first wall to the central axis of the battery cell in the direction orthogonal to the central axis of the battery cell is r, and h is set to be greater than or equal to 5/r and smaller than r, so that the electrode terminal is located on the first wall and far away from the center of the battery cell, and the electrode terminal (or the part where the electrode terminal is electrically connected with the first tab) and the second tab (or the part where the second tab is electrically connected with the first wall) are far away from each other as far as possible, thereby reducing the risk that the overlap joint of the positive electrode and the negative electrode of the battery cell causes the internal short circuit of the battery cell, and further enabling the battery to have higher reliability.

According to some embodiments of the application, the distance from the central axis of the electrode terminal to the central axis of the battery cell is h, satisfying h.gtoreq.3 mm.

In the above technical scheme, the distance h from the central axis of the electrode terminal to the central axis of the battery cell is set to be greater than or equal to 3mm, so that the electrode terminal is far away from the center of the battery cell, and the electrode terminal (or the position where the electrode terminal is electrically connected with the first tab) and the second tab (or the position where the second tab is electrically connected with the first wall) are far away from each other as far as possible, so that the risk of internal short circuit of the battery cell caused by overlapping of the anode and the cathode of the battery cell can be reduced, and the battery cell has higher reliability.

According to some embodiments of the application, the orthographic projection area of the electrode terminal is S1 and the orthographic projection area of the first wall is S along the thickness direction of the first wall, satisfying 5% s.ltoreq.s1.ltoreq.50% S.

In the above technical solution, along the thickness direction of the first wall, by setting the area of the orthographic projection of the electrode terminal to be greater than or equal to five percent of the area of the orthographic projection of the first wall, the risk of overlapping the electrode terminal and the second tab (or the position where the second tab and the first wall are electrically connected) can be effectively reduced under the condition that a certain overcurrent area exists between the electrode terminal and the first tab, and the reliability of the battery is improved. Meanwhile, the area of the orthographic projection of the electrode terminal is set to be less than or equal to fifty percent of the area of the orthographic projection of the first wall, so that the risk of mutual lap joint of the electrode terminal and the second lug (or the position where the second lug is electrically connected with the first wall) caused by overlarge electrode terminal is reduced, and the reliability of the battery is further improved.

According to some embodiments of the application, the battery cell further comprises a first adapter and a second adapter. The first adapter connects the first tab and the electrode terminal. The second adapter connects the second tab and the first wall.

In the technical scheme, the first adapter is arranged, so that the difficulty in electric connection between the first tab and the electrode terminal can be reduced, and current input and output are facilitated; through setting up the second adaptor, can reduce the degree of difficulty that second ear and first wall electricity are connected, do benefit to the input and the output of electric current. Among the battery monomer that electrode terminal set up eccentrically, because of electrode terminal set up eccentrically, can make first adaptor and second adaptor keep away from each other to can reduce the positive and negative pole overlap joint of battery monomer, cause the risk of battery monomer internal short circuit.

According to some embodiments of the application, the electrode assembly is a rolled electrode assembly, and the body portion has a central through hole penetrating the body portion in an axial direction of the body portion. The orthographic projection of the first adapter does not overlap with the central through hole along the thickness direction of the first wall.

In the above technical scheme, along the thickness direction of first wall, through set up the orthographic projection of first adaptor for not overlapping with central through-hole, can reduce first adaptor and second ear and second adaptor overlap joint and cause the risk of battery monomer internal short circuit, make the battery have higher reliability.

According to some embodiments of the application, the battery cell further comprises an insulator disposed between the electrode assembly and the first wall, the insulator insulating the first and second adapters.

In the technical scheme, through setting up the insulating part, can reduce first adaptor and second adaptor overlap joint effectively and cause the risk of battery monomer internal short circuit, make the battery have higher reliability.

According to some embodiments of the application, the first wall is provided with a liquid injection hole, the insulating member is provided with a first through hole, the liquid injection hole is at least partially opposite to the first through hole in the thickness direction of the first wall, and the first through hole is at least partially opposite to the central through hole.

In the technical scheme, the liquid injection hole is formed in the first wall and can be communicated with the central through hole through the first through hole, so that the injection efficiency of electrolyte can be improved on one hand, and the manufacturing efficiency of the battery cell is improved; on the other hand, the electrolyte can infiltrate the electrode assembly through the hole wall of the central through hole, so that the electrolyte has higher infiltration rate, and the improvement of the battery performance is facilitated.

According to some embodiments of the application, the electrode assembly is a rolled electrode assembly, and the body portion has a central through hole penetrating the body portion in an axial direction of the body portion. The minimum distance between the first lug and the second lug is L, the diameter of the central through hole is D, and L is more than or equal to D.

In the above technical scheme, the minimum distance L between the first tab and the second tab is defined to be greater than or equal to the diameter of the central through hole, so that the first tab and the second tab are at least spaced by a distance equal to the distance between the central through holes, the risk of internal short circuit of the battery cell caused by overlapping of the positive tab and the negative tab of the battery cell can be effectively reduced, and the battery has higher reliability.

According to some embodiments of the application, the first tab is a positive tab; or, the first tab is a negative tab.

In the above technical solution, in some embodiments, the first tab may be a positive electrode tab, that is, the electrode terminal may be used as a positive electrode to output current. In other embodiments, the first tab may be a negative tab, i.e., the electrode terminal may output current as a negative electrode.

According to some embodiments of the application, the battery cell is a sodium ion battery cell or a lithium ion battery cell.

The battery monomer provided in the technical scheme can be applied to sodium ion battery monomers and lithium ion battery monomers.

According to some embodiments of the application, an electrode assembly comprises a first pole piece and a second pole piece, the electrode assembly being a wound electrode assembly; the first pole piece comprises a plurality of first sub-pole lugs, the first sub-pole lugs form a first pole lug, the first pole piece of the innermost n1 circles is not provided with the first sub-pole lugs, and n1 is more than or equal to 1. And/or the second pole piece comprises a plurality of second sub-pole lugs, the second sub-pole lugs form the second pole lugs, the second pole piece of the innermost n2 circles is not provided with the second sub-pole lugs, and n2 is more than or equal to 1.

In the technical scheme, the first sub-tab is not arranged on the first pole piece of the innermost n1 circles, so that the first tab and the second tab are arranged at intervals, the short circuit risk between the first tab and the second tab is reduced, and the reliability of the battery is improved. Likewise, the second sub-tab is not arranged on the second pole piece of the innermost n2 circles, so that the second tab and the first tab are arranged at intervals, the risk of short circuit between the second tab and the first tab is reduced, and the reliability of the battery is improved.

According to some embodiments of the application, an electrode assembly comprises a first pole piece and a second pole piece, the electrode assembly being a wound electrode assembly; the first pole piece comprises a plurality of first sub-pole lugs, the first sub-pole lugs form a first pole lug, and the first pole piece of the outermost m1 circles is not provided with the first sub-pole lugs, and m1 is more than or equal to 1. And/or the second pole piece comprises a plurality of second sub-pole lugs, the second sub-pole lugs form the second pole lugs, the second pole piece with m2 circles at the outermost position is not provided with the second sub-pole lugs, and m2 is more than or equal to 1.

In the technical scheme, the first sub-tab is not arranged on the first pole piece of the outermost m1 ring, so that the first tab and the side wall of the shell are arranged at intervals, the risk of short circuit between the first tab and the shell is reduced, and the reliability of the battery is improved. Through do not set up the second sub-tab on the second pole piece of the m2 circles of outermost, can make second tab and first wall ear interval set up effectively to when reducing electrode assembly and putting into the shell, second tab and shell mutual interference lead to the impaired risk of second tab, are favorable to promoting the reliability of battery.

According to some embodiments of the application, the electrode assembly is a wound electrode assembly, and the first tab includes a plurality of first sub-tabs, each of which has the same size in a winding direction of the electrode assembly. Or, the size of the plurality of first sub-tabs in the winding direction of the electrode assembly gradually increases along the direction in which the inner ring of the electrode assembly is directed to the outer ring.

In some embodiments, the dimensions of each first sub-tab in the winding direction of the electrode assembly are set to be the same dimensions, so that the processing difficulty of the first sub-tab can be reduced (for example, when the tab is die-cut, the die-cutting dimension of each first sub-tab is the same, so that the die-cutting efficiency is high), and the manufacturing efficiency of the battery is improved. In some embodiments, by setting the size of the plurality of first sub-tabs in the winding direction of the electrode assembly to be gradually increased along the direction in which the inner ring of the electrode assembly is directed to the outer ring, the first tabs can fully utilize the inner space of the case, so that the first tabs have a larger area to improve the overcurrent capability between the first tabs and the electrode terminals, and the battery has better charge and discharge performance.

According to some embodiments of the application, the electrode assembly is a wound electrode assembly, and the second tab includes a plurality of second sub-tabs, each of which has the same size in a winding direction of the electrode assembly. Or, the size of the plurality of second sub-tabs in the winding direction of the electrode assembly gradually increases along the direction in which the inner ring of the electrode assembly is directed to the outer ring.

In the above technical solution, in some embodiments, the dimension of each second sub-tab in the winding direction of the electrode assembly is set to the same dimension, so that the processing difficulty of the second sub-tab can be reduced (for example, when the tab is die-cut, the die-cutting dimension of each second sub-tab is the same, so that the die-cutting efficiency is high), and the manufacturing efficiency of the battery is improved. In some embodiments, by setting the size of the plurality of second sub-tabs in the winding direction of the electrode assembly to be gradually increased along the direction in which the inner ring of the electrode assembly is directed to the outer ring, the second tabs can fully utilize the inner space of the case, so that the second tabs have a larger area to improve the overcurrent capability between the second tabs and the case, and the battery has better charge and discharge performance.

According to some embodiments of the application, the first tab has a first surface facing the first wall, the first surface being scalloped.

In the above technical scheme, through setting the first surface of the first tab to the fan-shaped structure, the first tab can fully utilize the inner space of the shell, so that the first tab has a larger area to improve the overcurrent capacity between the first tab and the electrode terminal, and the battery has better charge and discharge performance.

According to some embodiments of the application, the first surface has a first edge and a second edge distant from each other along the circumferential direction of the main body portion, the angle between the first edge and the second edge being α1,0 < α1+.270 °.

In the above technical scheme, the angle α1 formed between the first edge and the second edge of the first tab is set to be less than or equal to 270 degrees, so that the central angle of the first surface of the fan-shaped first tab is less than or equal to 270 degrees, and the phenomenon that the first tab and the second tab are easily overlapped due to overlarge space occupied by the first tab is relieved, so that the battery has higher reliability.

According to some embodiments of the application, the second tab has a second surface facing the first wall, the second surface being scalloped.

In the above technical scheme, through setting the second surface of the second lug to be the fan-shaped structure, can make full use of the inner space of shell for the second lug has great area in order to improve the overcurrent capacity between second lug and the shell, makes the battery have better charge-discharge performance.

According to some embodiments of the application, the second surface has third and fourth edges distant from each other along the circumferential direction of the main body portion, the angle between the third and fourth edges being α2,0 < α2+.180 °.

In the above technical scheme, the angle α2 formed between the third edge and the fourth edge of the second tab is set to be less than or equal to 180 degrees, so that the central angle of the second surface of the fan-shaped second tab is less than or equal to 180 degrees, and the phenomenon that the first tab and the second tab are easy to short-circuit due to overlarge space occupied by the second tab is relieved, so that the battery has higher reliability.

According to some embodiments of the application, the case includes a case body and an end cap, the electrode assembly is disposed inside the case body, and the end cap closes an opening of the case body. The first wall is an end cap.

In the above technical scheme, the first wall of shell sets up to the open-ended end cover that the shell is used for closed casing for the shell, and the battery monomer of adopting this kind of structure is convenient for adorn the electrode terminal on the end cover, and can reduce first utmost point ear and second utmost point ear respectively with the degree of difficulty of end cover and electrode terminal electricity connection to can reduce the manufacturing degree of difficulty of battery monomer, promote the manufacturing efficiency of battery.

According to some embodiments of the application, the housing is cylindrical or prismatic.

In the above technical scheme, through setting up the shell to be cylinder or prism, can improve the free space utilization of battery, in the battery, can make adjacent two battery monomer closely arrange, and then do benefit to the promotion of the volume energy density of battery.

In a second aspect, some embodiments of the present application also provide a battery, which includes the battery cell provided in the first aspect.

In a third aspect, some embodiments of the present application also provide an electrical device comprising a battery cell as provided in the first aspect, the battery cell being configured to provide electrical energy.

The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic illustration of a vehicle according to some embodiments of the present application;

fig. 2 is an exploded perspective view of a battery provided in some embodiments of the application;

Fig. 3 is a perspective view of a battery cell according to some embodiments of the application;

FIG. 4 is a top view of a battery cell according to some embodiments of the application;

fig. 5 is an internal schematic view of a partial structure of a battery cell according to some embodiments of the present application;

FIG. 6 is a schematic view of a first wall and electrode terminals in some embodiments of the application;

fig. 7 is an exploded perspective view of a battery cell according to some embodiments of the application;

FIG. 8 is a schematic view of an insulator in accordance with some embodiments of the application;

FIG. 9 is a top view of an electrode assembly according to some embodiments of the application;

FIG. 10 is a top view of an electrode assembly according to other embodiments of the present application;

fig. 11 is a top view of an electrode assembly according to other embodiments of the present application.

Icon: 100-cell; 10-battery cell; 11-a housing; 110-a first wall; 1100-a liquid injection hole; 111-a bottom plate; 112-a housing; 12-electrode terminals; 120-first stage; 121-a second section; 122-third stage; 123-insulating structure; 13-an electrode assembly; 130-a body portion; 1300-a central through hole; 131-a first tab; 1310-a first sub-tab; 1311-a first surface; 13110—a first edge; 13111-a second edge; 132-second pole ear; 1320-second sub-tab; 1321-a second surface; 13210-third edge; 13211-fourth edges; 14-a first adapter; 15-a second adapter; 16-an insulator; 160-insulator body; 161-dividing strips; 162-a first via; x-the thickness direction of the first wall; y-a circumferential direction of the body portion; 20-a box body; 21-a first tank body; 22-a second tank body; 1000-vehicle; 200-a controller; 300-motor.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description of the application and the claims and the description of the drawings above are intended to cover a non-exclusive inclusion. The terms first, second and the like in the description and in the claims or in the above-described figures, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order.

Reference in the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "attached" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art according to the specific circumstances.

The term "and/or" in the present application is merely an association relation describing the association object, and indicates that three kinds of relations may exist, for example, a and/or B may indicate: a exists alone, A and B exist together, and B exists alone. In the present application, the character "/" generally indicates that the front and rear related objects are an or relationship.

In the embodiments of the present application, the same reference numerals denote the same components, and detailed descriptions of the same components are omitted in different embodiments for the sake of brevity. It should be understood that the thickness, length, width, etc. dimensions of the various components in the embodiments of the application shown in the drawings, as well as the overall thickness, length, width, etc. dimensions of the integrated device, are merely illustrative and should not be construed as limiting the application in any way.

The term "plurality" as used herein refers to two or more (including two).

In the embodiment of the application, the battery cell can be a secondary battery, and the secondary battery refers to a battery cell which can activate the active material in a charging mode to continue to use after the battery cell discharges.

The battery cell may be a lithium ion battery, a sodium lithium ion battery, a lithium metal battery, a sodium metal battery, a lithium sulfur battery, a magnesium ion battery, a nickel hydrogen battery, a nickel cadmium battery, a lead storage battery, etc., which is not limited by the embodiment of the application.

The battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge of the battery cell, active ions (e.g., lithium ions) are inserted and extracted back and forth between the positive electrode and the negative electrode. The separator is arranged between the positive electrode and the negative electrode, can play a role in preventing the positive electrode and the negative electrode from being short-circuited, and can enable active ions to pass through.

In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

As an example, the positive electrode current collector has two surfaces opposing in its own thickness direction, and the positive electrode active material is provided on either or both of the two surfaces opposing the positive electrode current collector.

As an example, the positive electrode current collector may employ a metal foil or a composite current collector. For example, as the metal foil, surface-silver-treated aluminum, surface-silver-treated stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, titanium, or the like can be used. The composite current collector may include a polymeric material base layer and a metal layer. The composite current collector may be formed by forming a metal material (aluminum, aluminum alloy, nickel alloy, titanium alloy, silver alloy, etc.) on a polymer material substrate (e.g., a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

As an example, the positive electrode active material may include at least one of the following materials: lithium-containing phosphates, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as a battery positive electrode active material may be used. These positive electrode active materials may be used alone or in combination of two or more. Examples of lithium-containing phosphates may include, but are not limited to, lithium iron phosphate (e.g., liFePO ₄ (also abbreviated as LFP)), composite material of lithium iron phosphate and carbon, and manganese lithium phosphate (such as LiMnPO) ₄ ) At least one of a composite material of lithium manganese phosphate and carbon, and a composite material of lithium manganese phosphate and carbon.Examples of lithium transition metal oxides may include, but are not limited to, lithium cobalt oxides (e.g., liCoO) ₂ ) Lithium nickel oxide (e.g. LiNiO) ₂ ) Lithium manganese oxide (e.g. LiMnO ₂ 、LiMn ₂ O ₄ ) Lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (e.g., liNi) _1/3 Co _1/3 Mn _1/3 O ₂ (also referred to as NCM) ₃₃₃ ）、LiNi _0.5 Co _0.2 Mn _0.3 O ₂ (also referred to as NCM) ₅₂₃ ）、LiNi _0.5 Co _0.25 Mn _0.25 O ₂ (also referred to as NCM) ₂₁₁ ）、LiNi _0.6 Co _0.2 Mn _0.2 O ₂ (also referred to as NCM) ₆₂₂ ）、LiNi _0.8 Co _0.1 Mn _0.1 O ₂ (also referred to as NCM) ₈₁₁ ) Lithium nickel cobalt aluminum oxide (e.g. LiNi _0.85 Co _0.15 Al _0.05 O ₂ ) And at least one of its modified compounds and the like.

In some embodiments, the positive electrode may be a metal foam. The foam metal can be foam nickel, foam copper, foam aluminum, foam alloy, foam carbon or the like. When the metal foam is used as the positive electrode, the surface of the metal foam may not be provided with the positive electrode active material, but may be provided with the positive electrode active material. As an example, a lithium source material, which is lithium metal and/or a lithium-rich material, potassium metal or sodium metal, may also be filled and/or deposited within the foam metal.

In some embodiments, the negative electrode may be a negative electrode tab, which may include a negative electrode current collector.

As an example, the negative electrode current collector may employ a metal foil, a foam metal, or a composite current collector. For example, as the metal foil, silver-surface-treated aluminum or stainless steel, copper, aluminum, nickel, carbon electrode, carbon, nickel, titanium, or the like can be used. The foam metal can be foam nickel, foam copper, foam aluminum, foam alloy, foam carbon or the like. The composite current collector may include a polymeric material base layer and a metal layer. The composite current collector may be formed by forming a metal material (copper, copper alloy, nickel alloy, titanium alloy, silver alloy, etc.) on a polymer material substrate (e.g., a substrate of polypropylene, polyethylene terephthalate, polybutylene terephthalate, polystyrene, polyethylene, etc.).

As an example, the negative electrode sheet may include a negative electrode current collector and a negative electrode active material disposed on at least one surface of the negative electrode current collector.

As an example, the anode current collector has two surfaces opposing in its own thickness direction, and the anode active material is provided on either or both of the two surfaces opposing the anode current collector.

As an example, a negative active material for a battery cell, which is well known in the art, may be used. As an example, the anode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, and the like. The silicon-based material may be at least one selected from elemental silicon, silicon oxygen compounds, silicon carbon composites, silicon nitrogen composites, and silicon alloys. The tin-based material may be at least one selected from elemental tin, tin oxide, and tin alloys. However, the present application is not limited to these materials, and other conventional materials that can be used as a battery anode active material may be used. These negative electrode active materials may be used alone or in combination of two or more.

In some embodiments, the material of the positive electrode current collector may be aluminum and the material of the negative electrode current collector may be copper.

In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

In some embodiments, the separator is a separator film. The type of the separator may be various, and any known porous separator having good chemical stability and mechanical stability may be selected.

As an example, the material of the separator may include at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator may be a single-layer film or a multilayer composite film. When the separator is a multilayer composite film, the materials of the respective layers may be the same or different. The separator may be a single member located between the positive and negative electrodes, or may be attached to the surfaces of the positive and negative electrodes.

In some embodiments, the separator is a solid state electrolyte. The solid electrolyte is arranged between the anode and the cathode and plays roles in transmitting ions and isolating the anode and the cathode.

In some embodiments, the battery cell further includes an electrolyte that serves to conduct ions between the positive and negative electrodes. The electrolyte may be liquid, gel or solid. Wherein the liquid electrolyte comprises an electrolyte salt and a solvent.

In some embodiments, the electrolyte salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis-fluorosulfonyl imide, lithium bis-trifluoromethanesulfonyl imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalato borate, lithium difluorodioxaato phosphate, and lithium tetrafluorooxalato phosphate.

In some embodiments, the solvent may include at least one of ethylene carbonate, propylene carbonate, methylethyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methylpropyl carbonate, ethylpropyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1, 4-butyrolactone, sulfolane, dimethyl sulfone, methyl sulfone, and diethyl sulfone. The solvent may also be selected from ether solvents. The ether solvent may include one or more of ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, 1, 3-dioxolane, tetrahydrofuran, methyltetrahydrofuran, diphenyl ether, and crown ether.

The gel electrolyte comprises a skeleton network taking a polymer as an electrolyte and is matched with ionic liquid-lithium salt.

Wherein the solid electrolyte comprises a polymer solid electrolyte, an inorganic solid electrolyte and a composite solid electrolyte.

As examples, the polymer solid electrolyte may be polyether (polyethylene oxide), polysiloxane, polycarbonate, polyacrylonitrile, polyvinylidene fluoride, polymethyl methacrylate, single ion polymer, polyion liquid-lithium salt, cellulose, or the like.

As an example, the inorganic solid electrolyte may include one or more of oxide solid electrolyte (crystalline perovskite, sodium superconducting ion conductor, garnet, amorphous LiPON thin film), sulfide solid electrolyte (crystalline lithium super ion conductor (lithium germanium phosphorus sulfide, silver sulfur germanium mine), amorphous sulfide), and halide solid electrolyte, nitride solid electrolyte, and hydride solid electrolyte.

As an example, the composite solid electrolyte is formed by adding an inorganic solid electrolyte filler to a polymer solid electrolyte.

In some embodiments, the electrode assembly is a rolled structure. The positive plate and the negative plate are wound into a winding structure.

In some embodiments, the electrode assembly is provided with tabs that can conduct current away from the electrode assembly. The tab includes a positive tab and a negative tab.

In some embodiments, the battery cell may include a housing. The case is used to encapsulate the electrode assembly, the electrolyte, and the like. The shell can be a steel shell, an aluminum shell, a plastic shell (such as polypropylene), nickel steel, stainless steel, a composite metal shell (such as a copper-aluminum composite shell), an aluminum-plastic film or the like.

As an example, the battery cell may be a cylindrical battery cell or a prismatic battery cell.

Reference to a battery in accordance with an embodiment of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity.

In some embodiments, the battery may be a battery module, and when there are a plurality of battery cells, the plurality of battery cells are arranged and fixed to form one battery module.

In some embodiments, the battery may be a battery pack including a case and a battery cell, the battery cell or battery module being housed in the case.

In some embodiments, the tank may be part of the chassis structure of the vehicle. For example, a portion of the tank may become at least a portion of the floor of the vehicle, or a portion of the tank may become at least a portion of the cross member and the side member of the vehicle.

In some embodiments, the battery may be an energy storage device. The energy storage device comprises an energy storage container, an energy storage electric cabinet and the like.

The battery has the outstanding advantages of high energy density, small environmental pollution, large power density, long service life, wide application range, small self-discharge coefficient and the like, and is an important component of the development of new energy sources at present.

The battery cell generally includes a case and an electrode assembly accommodated in the case, the electrode assembly including a body part and tabs disposed on the body part, the tabs being used to output or input electric energy of the electrode assembly. In order to save the space occupied by the electrode assembly in the housing and improve the energy density of the battery cell, particularly in the battery cell with a cylindrical structure, in the related art, the positive and negative lugs of the electrode assembly are usually arranged at the same end of the main body part, so that the electrode assembly is in a structure with the same side lug, and the space occupied by the electrode assembly in the housing is saved. The positive and negative electrode lugs comprise first electrode lugs and second electrode lugs, the first electrode lugs are electrically connected with electrode terminals arranged on the first wall of the shell, and the second electrode lugs are electrically connected with the shell.

In the development of battery technology, how to improve the reliability of a battery is a technical problem to be solved in battery technology. At present, in the battery monomer that positive and negative electrode ear set up in the same one end of main part, electrode terminal sets up in the center of first wall, leads to the first electrode ear to be comparatively close to the second electrode ear with electrode terminal realization electrically connected's position, has electrode terminal or electrode terminal to realize electrically connected's position and second electrode ear overlap joint to make the risk that battery monomer positive and negative electrode overlap joint caused the battery monomer short circuit, influence the reliability of battery.

In view of this, in order to improve the problem that the battery cell is short-circuited due to the overlap joint of the positive electrode and the negative electrode of the battery cell, and the reliability of the battery is affected, some embodiments of the present application provide a battery cell with an electrode assembly having a tab protruding from the same side, wherein the battery cell includes a housing, an electrode terminal, and an electrode assembly. The electrode terminal is arranged on the first wall of the shell in an insulating manner. The central axis of the electrode terminal is arranged offset from the central axis of the battery cell, and the orthographic projection of the electrode terminal is at least partially overlapped with the orthographic projection of the first tab along the thickness direction x of the first wall.

In the battery cell with the structure, the electrode terminal is eccentrically arranged on the central axis of the battery cell, and the orthographic projection of the electrode terminal is arranged to at least partially overlap with the orthographic projection of the first tab along the thickness direction of the first wall, so that compared with the scheme that the electrode terminal is arranged in the battery cell in the middle, on one hand, the electrode terminal (or the position where the electrode terminal is electrically connected with the first tab) is far away from the second tab (or the position where the second tab is electrically connected with the first wall), thereby being capable of reducing the overlap joint of the positive electrode and the negative electrode of the battery cell and causing the risk of internal short circuit of the battery cell; on the other hand, the current transmission path between the electrode terminal and the first tab can be reduced, so that the current output or input capacity of the battery cell can be improved, and the battery has higher reliability.

The electrode assembly disclosed by the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but is not limited to the use of the electrode assembly. The power supply system with the battery cell, the battery and the like which are disclosed by the application can be used for forming the power utilization device, so that the problem of low reliability of the battery caused by internal short circuit of the battery cell due to overlap joint of the electrode lugs and the shell is solved.

The embodiment of the application provides an electric device using a battery as a power supply, wherein the electric device can be, but is not limited to, a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric car, a ship, a spacecraft and the like. Among them, the electric toy may include fixed or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric plane toys, and the like, and the spacecraft may include planes, rockets, space planes, and spacecraft, and the like.

For convenience of description, the following embodiments will take an electric device according to an embodiment of the present application as an example of a vehicle.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the application. The vehicle 1000 may be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid vehicle or a range-extended vehicle. The battery 100 is provided in the vehicle 1000, and the battery 100 may be provided at the bottom of the vehicle 1000, at the head of the vehicle 1000, or at the rear of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, for example, the battery 100 may be used as an operation power source or a use power source of the vehicle 1000, or the like. The vehicle 1000 may also include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to power the motor 300, for example, for operating power requirements during start-up, navigation, and travel of the vehicle 1000.

In some embodiments of the present application, battery 100 may not only be used as an operating power source or a utility power source for vehicle 1000, but may also be used as a drive power source for vehicle 1000 to provide drive power for vehicle 1000 instead of or in part instead of fuel oil or natural gas.

Referring to fig. 2, fig. 2 is an exploded perspective view of a battery 100 according to some embodiments of the present application, the battery 100 includes a case 20 and a battery cell 10, and the battery cell 10 is configured to be accommodated in the case 20.

The case 20 is used to provide an assembly space for the battery cell 10, and the case 20 may have various structures. In some embodiments, the case 20 may include a first case body 21 and a second case body 22, the first case body 21 and the second case body 22 being overlapped with each other, the first case body 21 and the second case body 22 together defining an assembly space for accommodating the battery cell 10. The second box body 22 may have a hollow structure with one end opened, the first box body 21 may have a plate-shaped structure, and the first box body 21 covers the open side of the second box body 22, so that the first box body 21 and the second box body 22 define an assembly space together; the first tank body 21 and the second tank body 22 may each have a hollow structure with one side opened, and the open side of the first tank body 21 may be closed to the open side of the second tank body 22.

Of course, the case 20 formed by the first case body 21 and the second case body 22 may be of various shapes, such as a cylinder, a rectangular parallelepiped, or a square, etc. Illustratively, in fig. 2, the case 20 is rectangular in shape.

In the battery 100, the number of the battery cells 10 provided in the case 20 may be one or more. When there are a plurality of battery cells 10 disposed in the case 20, the plurality of battery cells 10 may be connected in series or parallel or a series-parallel connection, and the series-parallel connection means that there are both series connection and parallel connection among the plurality of battery cells 10. The plurality of battery cells 10 can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery cells 10 is accommodated in the box body 20; of course, the battery 100 may also be a battery module form formed by connecting a plurality of battery cells 10 in series or parallel or series-parallel connection, and then connecting a plurality of battery modules in series or parallel or series-parallel connection to form a whole, and integrally accommodated in the case 20.

In some embodiments, the battery 100 may further include other structures, for example, the battery 100 may further include a bus member for connecting the plurality of battery cells 10 to achieve electrical connection between the plurality of battery cells 10.

Wherein each battery cell 10 may be a secondary battery or a primary battery; but not limited to, lithium sulfur batteries, sodium ion batteries, or magnesium ion batteries. The battery cell 10 may be in the shape of a cylinder, prism, or other shape, etc. Illustratively, in fig. 3, the battery cell 10 is of cylindrical configuration.

According to some embodiments of the present application, a battery cell 10 is provided, please refer to fig. 3-7, fig. 3 is a perspective view of the battery cell 10 according to some embodiments of the present application, fig. 4 is a top view of the battery cell 10 according to some embodiments of the present application, fig. 5 is an internal schematic view of a partial structure of the battery cell 10 according to some embodiments of the present application, fig. 6 is a schematic view of the first wall 110 and the electrode terminal 12 according to some embodiments of the present application, and fig. 7 is an exploded perspective view of the battery cell 10 according to some embodiments of the present application.

The battery cell 10 includes a case 11, an electrode terminal 12, and an electrode assembly 13. The housing 11 has a first wall 110. The electrode terminal 12 is provided on the first wall 110 in an insulating manner. The electrode assembly 13 is accommodated in the housing 11, the electrode assembly 13 includes a main body 130, a first tab 131 and a second tab 132, the polarities of the first tab 131 and the second tab 132 are opposite, the first tab 131 and the second tab 132 are disposed at one end of the main body 130 near the first wall 110, the first tab 131 is electrically connected with the electrode terminal 12, and the second tab 132 is electrically connected with the first wall 110. Wherein, the central axis of the electrode terminal 12 is offset from the central axis of the battery cell 10, and the orthographic projection of the electrode terminal 12 at least partially overlaps with the orthographic projection of the first tab 131 along the thickness direction x of the first wall.

The case 11 is a member for accommodating the electrode assembly 13, and the case 11 may also be used for accommodating an electrolyte such as an electrolytic solution. Referring to fig. 7, in some embodiments, the housing 11 includes a shell 112 and an end cap. The case 112 is formed inside with a receiving chamber for receiving the electrode assembly 13, the case 112 has an opening communicating with the receiving chamber, and an end cap is covered at the opening of the case 112 and forms a sealing connection to form a sealing space for receiving the electrode assembly 13 and electrolyte. Alternatively, the housing 11 may further include a bottom plate 111, and both ends of the case 112 are respectively formed with openings, one of which is closed by an end cap, and the other of which is closed by the bottom plate 111.

In some embodiments, the material of the housing 11 may be metal or a combination of metal and nonmetal, for example, the housing 11 may be made of metal, such as aluminum, copper, iron, aluminum, steel or aluminum alloy; for another example, a portion of the housing 11 may be made of metal and the remainder may be made of non-metal, e.g., an end cap of the housing 11 may be made of metal and the shell 112 or other portion of the housing 11 may be made of non-metal material.

In some embodiments, when assembling the battery cell 10, the electrode assembly 13 may be placed into the case 112, and the case 112 may be filled with the electrolyte, and then the end cap may be covered on the opening of the case 112, so as to complete the assembly of the battery cell 10. Alternatively, in some embodiments, when assembling the battery cell 10, the electrode assembly 13 may be placed into the case 112, then the end cap is covered on the opening of the case 112, then the electrolyte is filled into the case 112 through the electrolyte injection hole 1100 on the end cap, and then the electrolyte injection hole 1100 is closed to complete the assembly of the battery cell 10.

The housing 11 may be of various shapes, such as a cylinder or a prismatic structure, etc. The shape of the case 11 may be determined according to the specific shape of the electrode assembly 13. For example, if the electrode assembly 13 has a cylindrical structure, the case 11 having a cylindrical structure may be selected.

The first wall 110 is a partial structure of the case 11, and the first wall 110 may be insulation-mounted with an electrode terminal 12, the electrode terminal 12 being for connection with a first tab 131 of the electrode assembly 13. The first wall 110 may be made of a conductive material, for example, a metal material, such as aluminum, copper, iron, aluminum, steel, or an aluminum alloy, for example, for the first wall 110. In some embodiments, the first wall 110 may be electrically connected with the second tab 132 of the electrode assembly 13. In some embodiments, the first wall 110 may be an end cap of the housing 11. The shell 112 of the housing 11 surrounds the edge of the first wall 110, and in some embodiments, the first wall 110 is an end cap of the housing 11.

In some embodiments, the first wall 110 may be coupled to the shell 112 of the housing 11 by welding, bonding, clamping, or other coupling means. In some embodiments, the first wall 110 and the housing 112 may be integrally formed.

The electrode terminal 12 is an insulating member mounted to the first wall 110, and the electrode terminal 12 is adapted to be connected to the first tab 131 of the electrode assembly 13 for allowing a current to flow into or out of the second tab 132 through the electrode terminal 12. In some embodiments, the electrode terminal 12 may have a cylindrical structure, or a polygonal prismatic structure. In some embodiments, the electrode terminal 12 may be formed to revolve around a central axis of the electrode terminal 12.

In some embodiments, the electrode terminal 12 is made of a metal material, for example, made of aluminum, copper, iron, aluminum, steel, an alloy, or a composite metal.

In some embodiments, the electrode terminal 12 may be mounted on the first wall 110 through an insulating structure 123, for example, the first wall 110 is formed with a through hole, the peripheral wall of the electrode terminal 12 is sleeved with the insulating structure 123, and the insulating structure 123 is disposed between the first wall 110 and the electrode terminal 12. Referring to fig. 6, the electrode terminal 12 has a first section 120, a second section 121 and a third section 122 along a thickness direction x of the first wall, the first section 120 is located at an outer side of the case 11, the second section 121 is located in a through hole of the first wall 110, and the third section 122 is located at an inner side of the case 11, wherein a size of the first section 120 and the second section 121 is larger than a size of the through hole to limit displacement of the second section 121 in the thickness direction x of the first wall, so that the electrode terminal 12 is mounted in the through hole. The insulating structure 123 is disposed on the outer surfaces of the first, second and third sections 120, 121 and 122 such that the electrode terminal 12 is fixed to the first wall 110 through the insulating structure 123 on the one hand and the electrode terminal 12 is insulated from the first wall 110 through the insulating structure 123 on the other hand.

The electrode assembly 13 is a member in which electrochemical reaction occurs in the battery cell 10. The structure of the electrode assembly 13 may be various, and the electrode assembly 13 may be a roll-type structure formed by winding a positive electrode sheet, a separator, and a negative electrode sheet, and the body 130 of the electrode assembly 13 may have a cylindrical shape, for example. The separator is exemplified by a separator, and the separator may be made of at least one material selected from glass fiber, nonwoven fabric, polyethylene, polypropylene, and polyvinylidene fluoride.

The main body 130 is a region where the electrode assembly 13 chemically reacts in the battery cell 10, and the main body 130 is a structure in which a region where the positive electrode sheet is coated with the positive electrode active material layer, the separator, and a region where the negative electrode sheet is coated with the negative electrode active material layer are wound, and mainly operates by means of metal ions moving between the positive electrode sheet and the negative electrode sheet having opposite polarities.

In some embodiments, the thickness direction x of the first wall may be parallel to the height direction of the electrode assembly 13. The first tab 131 and the second tab 132 are disposed at one end of the main body 130. That is, the first tab 131 and the second tab 132 are disposed at the same end of the body 130 in the thickness direction x of the first wall, and at an end of the body 130 facing the first wall 110. The first tab 131 and the second tab 132 are used to output or input the positive and negative electrodes of the electrode assembly 13, respectively. If the first tab 131 is used for inputting or outputting the positive electrode of the electrode assembly 13, the first tab 131 is a part formed by mutually laminating and connecting the areas, not coated with the positive electrode active material layer, on the positive electrode sheet, and correspondingly, the second tab 132 is used for outputting or inputting the negative electrode of the electrode assembly 13, and the second tab 132 is a part formed by mutually laminating and connecting the areas, not coated with the negative electrode active material layer, on the negative electrode sheet; if the first tab 131 is used for outputting or inputting the negative electrode of the electrode assembly 13, the first tab 131 is a member formed by stacking and connecting the regions of the negative electrode sheet, which are not coated with the negative electrode active material layer, and correspondingly, the second tab 132 is a member formed by stacking and connecting the regions of the positive electrode sheet, which are not coated with the positive electrode active material layer, with each other, if the second tab 132 is used for inputting or outputting the positive electrode of the electrode assembly 13. Illustratively, in an embodiment of the present application, the first tab 131 is used for outputting or inputting the positive electrode of the electrode assembly 13, and the second tab 132 is used for outputting or inputting the negative electrode of the electrode assembly 13.

"the first tab 131 is electrically connected to the electrode terminal 12" is understood to mean that the first tab 131 is directly or indirectly connected to the electrode terminal 12 to achieve the electrical connection of the first tab 131 and the electrode terminal 12, and in some embodiments, the first tab 131 is directly connected to the electrode terminal 12; in some embodiments, the first tab 131 is connected with the electrode terminal 12 through the first adapter 14, wherein the first tab 131 and the electrode terminal 12 may be welded to the first adapter 14, respectively.

By "the second tab 132 is electrically connected to the first wall 110" it is understood that the second tab 132 is directly or indirectly connected to the housing 11 to effect electrical connection of the second tab 132 to the first wall 110. Illustratively, in some embodiments, the second tab 132 is directly connected to the first wall 110; in some embodiments, the second tab 132 is connected to the first wall 110 by the second adapter 15, e.g., the second tab 132 and the first wall 110 may be welded to the second adapter 15, respectively.

The "center axis arrangement of the battery cell 10" may be understood as a straight line parallel to the thickness direction x of the first wall and at the center of the battery cell 10, or may be understood as a rotation of the battery cell 10 around the center axis of the battery cell 10. In some embodiments, the central axis of the battery cell 10 may be disposed collinear with the central axis of the first wall 110. In some embodiments, the central axis of the battery cell 10 may be collinear with the central axis of the electrode assembly 13. Where the electrode assembly 13 is a wound electrode assembly, the central axis of the electrode assembly 13 may be collinear with the winding axis of the electrode assembly 13.

The "the center axis of the electrode terminal 12 is disposed offset from the center axis of the battery cell 10" may be understood as that the center axis of the electrode terminal 12 is disposed at a distance from the center axis of the battery cell 10, and may be understood as that the electrode terminal 12 is disposed eccentrically to the battery cell 10. Alternatively, it is understood that the electrode terminal 12 is eccentrically disposed to the first wall 110. Alternatively, it is understood that the portion where the electrode terminal 12 is connected to the first tab 131 to achieve electrical connection is spaced apart from the central axis of the battery cell 10.

By "the orthographic projection of the electrode terminal 12 and the orthographic projection of the first tab 131 at least partially overlap in the thickness direction x of the first wall" it is understood that the electrode terminal 12 may be disposed corresponding to the region where the first tab 131 is located and not disposed corresponding to the region where the second tab 132 is located in the thickness direction x of the first wall, on the one hand, the transmission path of the current between the electrode terminal 12 and the first tab 131 may be reduced, and on the other hand, the distance between the electrode terminal 12 and the second tab 132 may be increased.

In the above technical solution, by disposing the first tab 131 and the second tab 132 of the electrode assembly 13 on the same end face of the main body 130, it is beneficial to save the space occupied by the electrode assembly 13 in the direction from the electrode assembly 13 to the first wall 110, so as to increase the energy density of the battery cell 10 having such an electrode assembly 13. By eccentrically disposing the electrode terminal 12 on the central axis of the battery cell 10 and by disposing the orthographic projection of the electrode terminal 12 at least partially overlapping with the orthographic projection of the first tab 131 along the thickness direction x of the first wall, compared with the scheme in which the electrode terminal 12 is centrally disposed on the battery cell 10, on one hand, the electrode terminal 12 (or the portion where the electrode terminal 12 is electrically connected with the first tab 131) can be far away from the second tab 132 (or the portion where the second tab 132 is electrically connected with the first wall 110), so that the anode and cathode overlap of the battery cell 10 can be reduced, and the risk of internal short circuit of the battery cell 10 is caused; on the other hand, the current transmission path between the electrode terminal 12 and the first tab 131 can be reduced, so that the current output or input capability of the battery cell 10 can be improved, and the battery 100 has high reliability.

According to some embodiments of the present application, referring to fig. 5, the orthographic projection of the electrode terminal 12 falls within the orthographic projection of the first tab 131 in the thickness direction x of the first wall.

In some embodiments, along the thickness direction x of the first wall, the electrode terminal 12 may be disposed in a positive direction of the first tab 131, for example, the electrode terminal 12 is directly above the first tab 131 in fig. 5, and the orthographic projection of the electrode terminal 12 is less than or equal to the orthographic projection of the first tab 131, so that the orthographic projection of the first tab 131 can completely cover the orthographic projection of the electrode terminal 12.

In some embodiments, the electrode terminal 12 and the first tab 131 are disposed at intervals along the thickness direction x of the first wall, the first adapter 14 is disposed between the electrode terminal 12 and the first tab 131, the first adapter 14 may be disposed on the first tab 131 without exceeding the outer contour of the first tab 131, the lower surface of the first adapter 14 is connected with the first tab 131, and the upper surface of the first adapter 14 is connected with the electrode terminal 12.

In the above technical solution, along the thickness direction x of the first wall, the orthographic projection of the electrode terminal 12 is set to fall into the orthographic projection of the first tab 131, so that the electrode terminal 12 can be effectively far away from the second tab 132, so that the electrode terminal 12 (or the portion where the electrode terminal 12 and the first tab 131 are electrically connected) and the second tab 132 (or the portion where the second tab 132 and the first wall 110 are electrically connected) are far away from each other as far as possible, and therefore, the risk that the internal short circuit of the battery cell 10 is caused by overlapping the anode and the cathode of the battery cell 10 can be reduced, and further, the battery 100 has higher reliability.

According to some embodiments of the present application, referring to fig. 5, the electrode assembly 13 is a rolled electrode assembly, and the body part 130 has a central through hole 1300, the central through hole 1300 penetrating the body part 130 in an axial direction of the body part 130. In the thickness direction x of the first wall, the orthographic projection of the electrode terminal 12 does not overlap with the center through hole 1300.

The electrode assembly 13 is a winding type electrode assembly, and the electrode assembly 13 comprises a first pole piece, a second pole piece and a separation film, wherein the polarities of the first pole piece and the second pole piece are opposite, and the first pole piece, the second pole piece and the separation film are arranged in a stacked mode and are wound based on a winding axis. The central through hole 1300 is a central passage formed by winding the first and second electrode sheets and the separator of the main body 130 of the electrode assembly 13, and the central through hole 1300 may penetrate both ends of the main body 130 in the thickness direction x of the first wall. In some embodiments, the central axis of the central throughbore 1300 is collinear with the central axis of the battery cell 10. In some embodiments, the central axis of the central through hole 1300 may be parallel to the thickness direction x of the first wall.

By "the orthographic projection of the electrode terminal 12 does not overlap the central through hole 1300 in the thickness direction x of the first wall" it is understood that the electrode terminal 12 does not interfere with the central through hole 1300 in the thickness direction x perpendicular to the first wall, for example, the electrode terminal 12 is disposed at a distance from the central through hole 1300.

Compared with the prior art in which the portion of the electrode terminal 12 electrically connected to the first tab 131 is located in the position corresponding to the central through hole 1300, in the above technical scheme, along the thickness direction x of the first wall, by setting the orthographic projection of the electrode terminal 12 not to overlap with the central through hole 1300, the portion of the electrode terminal 12 electrically connected to the first tab 131 can be far away from the central through hole 1300, so that the electrode terminal 12 (or the portion of the electrode terminal 12 electrically connected to the first tab 131) and the second tab 132 (or the portion of the second tab 132 electrically connected to the first wall 110) are far away from each other as much as possible, and the risk that the battery cell 10 is internally short-circuited due to overlap between the positive and negative poles of the battery cell 10 can be reduced, thereby enabling the battery 100 to have higher reliability.

According to some embodiments of the present application, the first wall 110 is provided with a liquid injection hole 1100, and the liquid injection hole 1100 is at least partially opposite to the central through hole 1300 along the thickness direction x of the first wall.

The filling hole 1100 is a hole-like structure provided in the first wall 110, and the filling hole 1100 can be used to fill the inside of the case 11 with electrolyte. In some embodiments, the shape of the priming orifice 1100 may be a circular orifice, a square orifice, or an orifice of other shape.

In some embodiments, in the thickness direction x of the first wall, at least portions of the electrolyte injection hole 1100 and the central through hole 1300 overlap, so that the electrolyte injected by the electrolyte injection hole 1100 can flow into the central through hole 1300. In some embodiments, the central axis of the priming hole 1100 and the central axis of the central through hole 1300 may be disposed co-linearly.

The hole size of the liquid injection hole 1100 and the hole size of the central through hole 1300 may be the same or different, for example, the hole diameter of the liquid injection hole 1100 may be equal to or larger than the hole diameter of the central through hole 1300, and the hole diameter of the liquid injection hole 1100 may be smaller than the hole diameter of the central through hole 1300.

In the above technical solution, by eccentrically disposing the electrode terminal 12 on the first wall 110, the liquid injection hole 1100 can be disposed at the center of the first wall 110, and the liquid injection hole 1100 is opposite to at least part of the central through hole 1300, so that on one hand, the injection efficiency of the electrolyte can be improved, and thus the manufacturing efficiency of the battery cell 10 can be improved; on the other hand, the electrolyte may infiltrate the electrode assembly 13 through the wall of the central through hole 1300, so that the electrolyte has a higher infiltration rate, thereby facilitating the improvement of the performance of the battery 100.

In other embodiments, the injection port 1100 may be eccentrically disposed on the first wall 110. In other embodiments, the first wall 110 may not be provided with the liquid injection hole 1100, and the liquid injection hole 1100 may be provided at other positions of the housing 11; or the battery cell 10 may not be provided with the liquid injection hole 1100.

According to some embodiments of the present application, the central axis of the liquid injection hole 1100 coincides with the central axis of the battery cell 10.

In some embodiments, the fill port 1100 may be disposed coaxially with the first wall 110. In some embodiments, the injection hole 1100 may be centrally disposed on the first wall 110 such that the central axis of the injection hole 1100 and the central axis of the central through hole 1300 are disposed co-linearly.

In the above technical solution, by overlapping the central axis of the liquid injection hole 1100 with the central axis of the battery cell 10, on one hand, the electrolyte can be rapidly injected into the housing 11 through the liquid injection hole 1100, so as to improve the manufacturing efficiency of the battery cell 10; on the other hand, the electrolyte may infiltrate the electrode assembly 13 through the wall of the central through hole 1300, so that the electrolyte has a higher infiltration rate, thereby facilitating the improvement of the performance of the battery 100.

According to some embodiments of the present application, referring to fig. 5, the distance from the central axis of the electrode terminal 12 to the central axis of the battery cell 10 is h. The maximum distance from the edge of the first wall 110 to the central axis of the battery cell 10 along the direction orthogonal to the central axis of the battery cell 10 is r, satisfying r/5.ltoreq.h < r.

"the distance from the center axis of the electrode terminal 12 to the center axis of the battery cell 10 is h", in some embodiments, it is understood that the distance from the center of the electrode terminal 12 to the center of the battery cell 10 is h in a plane perpendicular to the electrode terminal 12; in some embodiments, it can also be understood that the distance between the exact center of the electrode terminal 12 and the exact center of the first wall 110 is h in a plane perpendicular to the electrode terminal 12; in some embodiments, it is also understood that the distance between the very center of the electrode terminal 12 and the very center of the electrode assembly 13 is h in a plane perpendicular to the electrode terminal 12.

"the maximum distance of the edge of the first wall 110 to the central axis of the battery cell 10 in the direction orthogonal to the central axis of the battery cell 10 is r" may be understood as the maximum distance of the center of the battery cell 10 from the outer edge of the battery cell 10 on a plane perpendicular to the electrode terminals 12. For example, when the battery cell 10 has a cylindrical structure, the surface of the first wall 110 may be circular, and r may be a radius of the first wall 110.

In some embodiments, h may be greater than or equal to one fifth r, e.g., h is r/5, r/4, r/3, r/2, or r.

In the above technical solution, the distance from the central axis of the electrode terminal 12 to the central axis of the battery cell 10 is h, the maximum distance from the edge of the first wall 110 to the central axis of the battery cell 10 in the direction orthogonal to the central axis of the battery cell 10 is r, and by setting h to be greater than or equal to 5/r and less than r, so that the electrode terminal 12 is located on the first wall 110 and far away from the center of the battery cell 10, the electrode terminal 12 (or the portion where the electrode terminal 12 and the first tab 131 are electrically connected) and the second tab 132 (or the portion where the second tab 132 and the first wall 110 are electrically connected) are separated from each other as far as possible, so that the risk that the battery cell 10 is internally shorted due to overlap of the positive and negative poles of the battery cell 10 can be reduced, and thus the battery 100 has higher reliability.

In other embodiments, h may be less than one fifth r.

According to some embodiments of the present application, the distance from the central axis of the electrode terminal 12 to the central axis of the battery cell 10 is h, satisfying h.gtoreq.3 mm.

"the distance from the center axis of the electrode terminal 12 to the center axis of the battery cell 10 is h, satisfying h.gtoreq.3 mm" is understood to mean that the distance h between the center of the electrode terminal 12 and the center of the battery cell 10 is greater than or equal to 3mm on a plane perpendicular to the electrode terminal 12; in some embodiments, it is also understood that the distance h between the very center of the electrode terminal 12 and the very center of the first wall 110 is greater than or equal to 3mm in a plane perpendicular to the electrode terminal 12; in some embodiments, it is also understood that the distance h between the very center of the electrode terminal 12 and the very center of the electrode assembly 13 is greater than or equal to 3mm in a plane perpendicular to the electrode terminal 12.

In some embodiments h may be 3mm, 4mm, 5mm, or 6mm, among other values.

In the above technical solution, by setting the distance h from the central axis of the electrode terminal 12 to the central axis of the battery cell 10 to be greater than or equal to 3mm, the electrode terminal 12 can be far away from the center of the battery cell 10, so that the electrode terminal 12 (or the portion where the electrode terminal 12 and the first tab 131 are electrically connected) and the second tab 132 (or the portion where the second tab 132 and the first wall 110 are electrically connected) are far away from each other as far as possible, thereby reducing the risk that the positive and negative poles of the battery cell 10 overlap to cause internal short circuit of the battery cell 10, and further enabling the battery 100 to have higher reliability.

In other embodiments, h may be less than 3mm, for example h may be 2mm.

According to some embodiments of the present application, the orthographic projection area of the electrode terminal 12 is S1 and the orthographic projection area of the first wall 110 is S along the thickness direction x of the first wall, satisfying 5% s.ltoreq.s1.ltoreq.50% S.

"the area of the orthographic projection of the electrode terminal 12 in the thickness direction x of the first wall is S1" is understood to be the area of the projection of the electrode terminal 12 in the thickness direction x of the first wall is S1. In some embodiments, "the area of the orthographic projection of the electrode terminal 12 in the thickness direction x of the first wall" may also be understood as an area of the electrode terminal 12 for electrical connection with the first tab 131 being S1, or an area of connection of the electrode terminal 12 with the first adapter 14 being S1. In some embodiments, "the area of the orthographic projection of the electrode terminal 12 in the thickness direction x of the first wall" may also be understood as the area of the end face of the electrode terminal 12 in the thickness direction x of the first wall being S1.

The orthographic projection area of the first wall 110 is S, and may be an area of an outer surface or an inner surface of the first wall 110 is S. The orthographic projection area S of the first wall 110 may be greater than the sum of the surface areas of the first tab 131 and the second tab 132.

In some embodiments, when the first wall 110 is circular, the area S of the orthographic projection of the first wall 110 in the thickness direction x of the first wall may be calculated by an area formula of the circle based on the radius of the first wall 110.

In some embodiments, the orthographic projection area S1 of the electrode terminal 12 may be greater than or equal to 5% of the orthographic projection area of the first wall 110, for example, S1 may be 5%, 6%, 7%, or other values.

In some embodiments, the orthographic projection area S1 of the electrode terminal 12 may be less than or equal to 50% of the orthographic projection area of the first wall 110, for example, S1 may be 50% S, 49% S, 48% S, or other values greater than or equal to 5%S and raining or equal to 50% S.

In the above-mentioned technical solution, by setting the area of the orthographic projection of the electrode terminal 12 to be greater than or equal to five percent of the area of the orthographic projection of the first wall 110 along the thickness direction x of the first wall, the risk of overlapping the electrode terminal 12 with the second tab 132 (or the portion where the second tab 132 is electrically connected with the first wall 110) can be effectively reduced under the condition that a certain overcurrent area exists between the electrode terminal 12 and the first tab 131, and the reliability of the battery 100 is improved. Meanwhile, by setting the area of the orthographic projection of the electrode terminal 12 to be less than or equal to fifty percent of the area of the orthographic projection of the first wall 110, the risk of overlapping the electrode terminal 12 and the second tab 132 (or the portion where the second tab 132 and the first wall 110 are electrically connected) due to the oversized electrode terminal 12 is reduced, thereby improving the reliability of the battery 100.

According to some embodiments of the present application, referring to fig. 7, the battery cell 10 further includes a first adapter 14 and a second adapter 15. The first adapter 14 connects the first tab 131 and the electrode terminal 12. The second adapter 15 connects the second tab 132 and the first wall 110.

The first adapter 14 is a member disposed between the first tab 131 and the electrode terminal 12, and the first adapter 14 is made of a conductive material, for example, the material of the first adapter 14 may be aluminum, copper, iron, aluminum, steel, stainless steel, nickel steel, or aluminum alloy. The material of the first adapter 14 may be the same as that of the first tab 131. The material of the first adapter 14 may be the same as that of the electrode terminal 12.

The connection relationship between the first adapter 14 and the first tab 131 includes, but is not limited to, welding, bonding, clamping, or other connection relationship through other connection members. The connection relationship of the first adapter 14 and the electrode terminal 12 includes, but is not limited to, welding, bonding, clamping, or other connection relationship by other connection members.

The second adaptor 15 is a component disposed between the second lug 132 and the first wall 110, and the second adaptor 15 is made of a conductive material, for example, the material of the second adaptor 15 may be aluminum, copper, iron, aluminum, steel, stainless steel, nickel steel, or aluminum alloy. The material of the second adapter 15 may be the same as the material of the second tab 132. The material of the second adapter 15 may be the same as the material of the first wall 110.

The connection relationship between the second adapter 15 and the second lug 132 includes, but is not limited to, welding, bonding, clamping, or other connection relationship through other connection members. The connection relationship between the second adapter 15 and the first wall 110 includes, but is not limited to, welding, bonding, clamping, or other connection relationship through other connection members.

In the above technical solution, by providing the first adapter 14, the difficulty in electrically connecting the first tab 131 and the electrode terminal 12 can be reduced, which is beneficial to input and output of current; by providing the second adaptor 15, the difficulty in electrically connecting the second lug 132 with the first wall 110 can be reduced, which is beneficial to input and output of current. In the battery cell 10 with the eccentric electrode terminal 12, the first adapter 14 and the second adapter 15 can be far away from each other due to the eccentric electrode terminal 12, so that the risk of internal short circuit of the battery cell 10 caused by overlapping of the positive electrode and the negative electrode of the battery cell 10 can be reduced.

According to some embodiments of the present application, the electrode assembly 13 is a rolled electrode assembly, and the body part 130 has a central through hole 1300, and the central through hole 1300 penetrates the body part 130 in an axial direction of the body part 130. The orthographic projection of the first adapter 14 does not overlap the central through hole 1300 in the thickness direction x of the first wall.

The electrode assembly 13 is a winding type electrode assembly, and the electrode assembly 13 comprises a first pole piece, a second pole piece and a separation film, wherein the polarities of the first pole piece and the second pole piece are opposite, and the first pole piece, the second pole piece and the separation film are arranged in a stacked mode and are wound based on a winding axis. The central through hole 1300 is a central passage formed by winding the first and second electrode sheets and the separator of the main body 130 of the electrode assembly 13, and the central through hole 1300 may penetrate both ends of the main body 130 in the thickness direction x of the first wall.

By "the orthographic projection of the first adapter 14 does not overlap the central through hole 1300 in the thickness direction x of the first wall" it is understood that the first adapter 14 does not interfere with the central through hole 1300, i.e. the first adapter 14 does not obstruct the central through hole 1300.

In the above-mentioned technical solution, along the thickness direction x of the first wall, by setting the orthographic projection of the first adapter 14 not to overlap with the central through hole 1300, the risk that the first adapter 14 overlaps with the second lug 132 and the second adapter 15 to cause the internal short circuit of the battery cell 10 can be reduced, so that the battery 100 has higher reliability.

According to some embodiments of the present application, the battery cell 10 further includes an insulating member 16, the insulating member 16 being disposed between the electrode assembly 13 and the first wall 110, the insulating member 16 insulating the first and second adapters 14 and 15.

The insulating member 16 is disposed between the electrode assembly 13 and the first wall 110, and the insulating member 16 has an insulating property, and is capable of insulating and isolating the first and second switching members 14 and 15, and is capable of insulating and isolating the first switching member 14 and the case 11. In some embodiments, the insulator 16 may be sheet-like, plate-like, or ring-like, etc. In some embodiments, the insulating member 16 may be a rubber member, a silicone member, a plastic member, or the like. In some embodiments, the insulator 16 is made of an insulating material, such as polypropylene, polyethylene, or other materials having insulating properties.

In some embodiments, the insulator 16 may be the lower plastic of the battery cell 10.

Referring to fig. 8, fig. 8 is a schematic view of an insulating member 16 according to some embodiments of the present application. The insulator 16 includes an insulator body 160 and a separation bar 161, the insulator body 160 is ring-shaped, the insulator 16 may be disposed between the electrode assembly 13 and the first wall 110, the first tab 131 and the second tab 132 may support the lower surface of the insulator body 160 (in other embodiments, the insulator body 160 may be supported on the end surface of the main body 130, the first tab 131 and the second tab 132 are located inside the insulator body 160), the upper surface of the insulator body 160 faces the first wall 110, and the separation bar 161 is disposed inside the insulator body 160 to divide the inner space of the insulator body 160 into two subspaces, respectively, one subspace accommodates the first adapter 14, and the other subspace accommodates the second adapter 15.

In the above technical solution, by providing the insulating member 16, the risk of internal short circuit of the battery cell 10 caused by overlapping the first adapter member 14 and the second adapter member 15 can be effectively reduced, so that the battery 100 has higher reliability.

According to some embodiments of the present application, referring to fig. 7 and 8, the first wall 110 is provided with a liquid injection hole 1100, the insulating member 16 is provided with a first through hole 162, the liquid injection hole 1100 is at least partially opposite to the first through hole 162 along the thickness direction x of the first wall, and the first through hole 162 is at least partially opposite to the central through hole 1300.

The first through-hole 162 is a hole-like structure provided to the insulating member 16, and the first through-hole 162 may communicate with the electrolyte injection hole 1100 such that the electrolyte injected from the electrolyte injection hole 1100 can enter the electrode assembly 13 through the first through-hole 162. In some embodiments, the first through hole 162 may be in the shape of a circular hole, a square hole, or a hole of other shape.

By "the injection hole 1100 is at least partially opposite to the first through hole 162 and the first through hole 162 is at least partially opposite to the central through hole 1300" it is understood that the injection hole 1100 communicates with the first through hole 162 and the first through hole 162 communicates with the central through hole 1300, so that the electrolyte injected from the injection hole 1100 can enter the electrode assembly 13 through the first through hole 162 and the central through hole 1300.

In some embodiments, the priming hole 1100, the first through hole 162, and the central through hole 1300 are coaxially disposed, or the priming hole 1100, the first through hole 162, and the central through hole 1300 are not coaxially disposed.

In some embodiments, the hole size of the third through hole may be the same as or different from the size of the priming hole 1100. For example, the aperture of the third through hole may be equal to or larger than the aperture of the liquid injection hole 1100, and the aperture of the liquid injection hole 1100 may be larger than the aperture of the third through hole.

In the above technical solution, by providing the liquid injection hole 1100 on the first wall 110, and the liquid injection hole 1100 can be communicated with the central through hole 1300 through the first through hole 162, on one hand, the injection efficiency of the electrolyte can be improved, thereby improving the manufacturing efficiency of the battery cell 10; on the other hand, the electrolyte may infiltrate the electrode assembly 13 through the wall of the central through hole 1300, so that the electrolyte has a higher infiltration rate, thereby facilitating the improvement of the performance of the battery 100.

Referring to fig. 9, fig. 9 is a top view of an electrode assembly 13 according to some embodiments of the present application. The electrode assembly 13 is a wound electrode assembly, and the main body 130 has a central through hole 1300, and the central through hole 1300 penetrates the main body 130 in the axial direction of the main body 130. The minimum distance between the first tab 131 and the second tab 132 is L, and the diameter of the central through hole 1300 is D, so that L is larger than or equal to D.

The "minimum distance between the first tab 131 and the second tab 132 is L", and the minimum distance between the first tab 131 and the second tab 132 may be L.

In some embodiments, the minimum distance L of the first tab 131 and the second tab 132 may be greater than or equal to the diameter D of the central through hole 1300.

In the above technical solution, the minimum distance L between the first tab 131 and the second tab 132 is defined to be greater than or equal to the diameter of the central through hole 1300, so that the first tab 131 and the second tab 132 are at least spaced by a distance directly equal to the distance between the central through holes 1300, which can effectively reduce the risk that the positive and negative tabs of the battery cell 10 overlap to cause the internal short circuit of the battery cell 10, so that the battery 100 has higher reliability.

According to some embodiments of the application, the first tab 131 is a positive tab; or, the first tab 131 is a negative electrode tab.

In some embodiments, the first tab 131 may be a positive tab, the first tab 131 is a positive tab, and the electrode terminal 12 outputs or inputs a positive current. When the first tab 131 is a positive electrode tab, the material of the first tab 131 and/or the electrode terminal 12 may be aluminum; the second lug 132 and/or the first wall 110 may be made of stainless steel or nickel steel.

In some embodiments, the first tab 131 may be a negative tab, the first tab 131 being a negative tab, and the electrode terminal 12 outputting or inputting a negative current. When the first tab 131 is a negative tab, the second tab 132 and/or the first wall 110 may be made of stainless steel, nickel steel, aluminum, or the like.

In the above technical solution, in some embodiments, the first tab 131 may be a positive electrode tab, that is, the electrode terminal 12 may output current as a positive electrode. In other embodiments, the first tab 131 may be a negative tab, that is, the electrode terminal 12 may output current as a negative electrode.

According to some embodiments of the present application, the battery cell 10 is a sodium ion battery cell 10 or a lithium ion battery cell 10.

In some embodiments, when the battery cell 10 is a sodium ion battery cell 10, the material of the second tab 132 and/or the first wall 110 may be stainless steel or nickel steel or aluminum when the first tab 131 is a positive tab.

The battery cell 10 provided in the above technical scheme can be applied to a sodium ion battery cell 10 and also can be applied to a lithium ion battery cell 10.

According to some embodiments of the present application, the electrode assembly 13 includes a first electrode sheet and a second electrode sheet, and the electrode assembly 13 is a wound electrode assembly; the first pole piece comprises a plurality of first sub-tabs 1310, the first sub-tabs 1310 form the first tab 131, and the first pole piece of the innermost n1 circles is not provided with the first sub-tab 1310, and n1 is more than or equal to 1. And/or, the second pole piece comprises a plurality of second sub-pole lugs 1320, the second pole lugs 1320 form the second pole lug 132, the second pole piece of the innermost n2 circles is not provided with the second sub-pole lugs 1320, and n2 is more than or equal to 1.

The electrode assembly 13 is a wound electrode assembly, the electrode assembly 13 includes first and second electrode sheets having opposite polarities and a separator, the first and second electrode sheets and the separator are stacked and wound based on a winding axis, and a central through hole 1300 penetrating the body portion 130 is formed at the center of the body portion 130.

In some embodiments, the wound electrode assembly 13 includes a plurality of first electrode sheets, the first tab 131 includes a plurality of first sub-tabs 1310, and the number of the first sub-tabs 1310 may be smaller than the number of the first electrode sheets. For example, the first pole piece of the innermost n1 turns is not provided with the first sub-tab 1310, e.g., the first pole piece of the innermost first turn and the second turn is not provided with the first sub-tab 1310, so that a certain distance exists between the first tab 131 and the central through hole 1300. Where the value of n1 may be 1 or an integer greater than 1, for example, the first pole piece of the innermost 1 turn, the innermost 2 turns, the innermost 3 turns, the innermost 4 turns, or the innermost more turns is not provided with the first sub-tab 1310. Referring to fig. 10, fig. 10 is a top view of an electrode assembly 13 according to still other embodiments of the present application. There is a certain distance between the edge of the first tab 131 closest to the central through hole 1300 and the central through hole 1300.

In some embodiments, the wound electrode assembly 13 includes a plurality of turns of the second electrode sheet, the second tab 132 includes a plurality of second sub-tabs 1320, and the number of second sub-tabs 1320 may be less than the number of turns of the second electrode sheet. For example, the second pole piece of the innermost n2 turns is not provided with the second sub-tab 1320, e.g., the second pole pieces of the innermost first turn and the second turn are not provided with the second sub-tab 1320, such that a certain distance is provided between the second tab 132 and the central through hole 1300. Where n2 may be 1 or an integer greater than 1, for example, the second tab of the innermost 1 turn, the innermost 2 turns, the innermost 3 turns, the innermost 4 turns, or the innermost more turns is not provided with the second sub-tab 1320. Referring to fig. 10, there is a distance between the edge of the second tab 132 closest to the central through hole 1300 and the central through hole 1300.

In the above technical solution, the first sub-tab 1310 is not disposed on the first pole piece of the innermost n1 turns, so that the first tab 131 and the second tab 132 are disposed at intervals, thereby reducing the risk of short circuit between the first tab 131 and the second tab 132, and being beneficial to improving the reliability of the battery 100. Likewise, the second sub-tab 1320 is not arranged on the second pole piece of the innermost n2 turns, so that the second tab 132 and the first tab 131 can be effectively arranged at intervals, thereby reducing the risk of short circuit between the second tab 132 and the first tab 131 and being beneficial to improving the reliability of the battery 100.

According to some embodiments of the present application, the electrode assembly 13 includes a first electrode sheet and a second electrode sheet, and the electrode assembly 13 is a wound electrode assembly; the first pole piece comprises a plurality of first sub-tabs 1310, the first sub-tabs 1310 form the first tab 131, and the first pole piece with m1 circles at the outermost position is not provided with the first sub-tabs 1310, and m1 is more than or equal to 1. And/or, the second pole piece comprises a plurality of second sub-pole lugs 1320, the second pole lugs 1320 form the second pole lug 132, and the second pole piece of the outermost m2 circles is not provided with the second sub-pole lugs 1320, and m2 is more than or equal to 1.

The electrode assembly 13 is a winding type electrode assembly, and the electrode assembly 13 comprises a first pole piece, a second pole piece and a separation film, wherein the polarities of the first pole piece and the second pole piece are opposite, and the first pole piece, the second pole piece and the separation film are arranged in a stacked mode and are wound based on a winding axis.

In some embodiments, the wound electrode assembly 13 includes a plurality of first electrode sheets, the first tab 131 includes a plurality of first sub-tabs 1310, and the number of the first sub-tabs 1310 may be smaller than the number of the first electrode sheets. For example, the first pole piece of the outermost m1 turn is not provided with the first sub-tab 1310, e.g., the first pole pieces of the outermost first turn and the second turn are not provided with the first sub-tab 1310, so that a certain distance is provided between the first tab 131 and the outer circumferential surface of the main body 130. Where the value of m1 may be 1 or an integer greater than 1, for example, the first pole piece of the outermost 1 turn, the outermost 2 turns, the outermost 3 turns, the outermost 4 turns, or the outermost more turns is not provided with the first sub-tab 1310. Referring to fig. 10, there is a certain distance between the edge of the first tab 131 closest to the outer circumferential surface of the body 130 and the outer circumferential surface of the body 130.

In some embodiments, the wound electrode assembly 13 includes a plurality of turns of the second electrode sheet, the second tab 132 includes a plurality of second sub-tabs 1320, and the number of second sub-tabs 1320 may be less than the number of turns of the second electrode sheet. For example, the second pole piece of the outermost m2 turn is not provided with the second sub-tab 1320, e.g., the second pole pieces of the outermost first turn and the second turn are not provided with the second sub-tab 1320, so that there is a certain distance between the second tab 132 and the outer circumferential surface of the main body portion 130. Where the value of m2 may be 1 or an integer greater than 1, for example, the second pole piece of the outermost 1 turn, the outermost 2 turns, the outermost 3 turns, the outermost 4 turns, or the outermost more turns is not provided with the second sub-tab 1320. Referring to fig. 10, there is a certain distance between the edge of the second lug 132 closest to the outer peripheral surface of the main body 130 and the outer peripheral surface of the main body 130.

In the above technical solution, the first sub-tab 1310 is not disposed on the first pole piece of the outermost m1 ring, so that the first tab 131 and the housing 112 are disposed at intervals, thereby reducing the risk of short circuit between the first tab 131 and the housing 112, and facilitating the improvement of the reliability of the battery 100. By not providing the second sub-tab 1320 on the second pole piece of the outermost m2 turn, the second tab 132 and the first wall 110 can be effectively arranged at a spacing, so that the risk that the second tab 132 is damaged due to mutual interference between the second tab 132 and the casing 112 when the electrode assembly 13 is put into the casing 11 is reduced, and the reliability of the battery 100 is improved.

According to some embodiments of the present application, the electrode assembly 13 is a wound electrode assembly, and the first tab 131 includes a plurality of first sub-tabs 1310, each of which has the same size in the winding direction of the electrode assembly 13. Or, the plurality of first sub-tabs 1310 gradually increases in size in the winding direction of the electrode assembly 13 in a direction in which the inner ring of the electrode assembly 13 is directed to the outer ring.

The wound electrode assembly 13 includes a plurality of first electrode tabs, the first tab 131 includes a plurality of first sub-tabs 1310, and the number of the first sub-tabs 1310 may be equal to or less than the number of the first electrode tabs.

The "the size of each first sub-tab 1310 is the same in the winding direction of the electrode assembly 13" may be understood as that the adjacent first sub-tabs 1310 are the same in size in the winding direction such that the first tab 131 is a regular shape, for example, the first tab 131 is square, or the first tab 131 is approximately square. Illustratively, referring to fig. 10, each of the first sub-tabs 1310 has the same size in the winding direction of the electrode assembly 13, and the surface of the first tab 131 is square, or approximately square.

The "the plurality of first sub-tabs 1310 gradually increases in size in the winding direction of the electrode assembly 13 along the direction in which the inner ring of the electrode assembly 13 is directed to the outer ring" is understood to mean that the first sub-tab 1310 at the inner ring is smaller in size in the winding direction than the first sub-tab 1310 at the outer ring, among the adjacent two first sub-tabs 1310. Illustratively, the plurality of first sub-tabs 1310 gradually increases in size in the winding direction of the electrode assembly 13 along the direction in which the inner ring of the electrode assembly 13 is directed toward the outer ring, and the surface of the first tab 131 is fan-shaped or approximately fan-shaped (see fig. 11, fig. 11 is a top view of the electrode assembly 13 in other embodiments of the present application).

In the above technical solution, in some embodiments, the dimension of each first sub-tab 1310 in the winding direction of the electrode assembly 13 is set to the same dimension, so that the processing difficulty of the first sub-tab 1310 can be reduced (for example, when the tabs are die-cut, the die-cutting dimension of each first sub-tab 1310 is the same, so that the die-cutting efficiency is high), and the manufacturing efficiency of the battery 100 is improved. In some embodiments, by setting the size of the plurality of first sub-tabs 1310 in the winding direction of the electrode assembly 13 to be gradually increased along the direction in which the inner ring of the electrode assembly 13 is directed to the outer ring, the first tabs 131 can be made to fully utilize the inner space of the case 11 such that the first tabs 131 have a larger area to improve the overcurrent capability between the first tabs 131 and the electrode terminals 12, so that the battery 100 has superior charge and discharge performance.

According to some embodiments of the present application, the electrode assembly 13 is a wound electrode assembly, and the second tab 132 includes a plurality of second sub-tabs 1320, each of the second sub-tabs 1320 having the same size in the winding direction of the electrode assembly 13. Or, the plurality of second sub-tabs 1320 gradually increases in size in the winding direction of the electrode assembly 13 in a direction in which the inner ring of the electrode assembly 13 is directed to the outer ring.

The wound electrode assembly 13 includes a plurality of second electrode tabs 132, and the second electrode tabs 132 include a plurality of second sub-electrode tabs 1320, and the number of the second sub-electrode tabs 1320 may be equal to or less than the number of the second electrode tabs.

The "the size of each second sub-tab 1320 is the same in the winding direction of the electrode assembly 13" may be understood as that the adjacent second sub-tabs 1320 are the same in size in the winding direction such that the second tab 132 is a regular shape, for example, the second tab 132 is square, or the second tab 132 is approximately square.

By "the plurality of second sub-tabs 1320 gradually increase in size in the winding direction of the electrode assembly 13 along the direction in which the inner ring of the electrode assembly 13 is directed to the outer ring" it is understood that the second sub-tab 1320 in the inner ring is smaller in size in the winding direction than the second sub-tab 1320 in the outer ring along the adjacent two second sub-tabs 1320. Illustratively, in fig. 10, the plurality of first sub-tabs 1310 gradually increases in size in the winding direction of the electrode assembly 13 in a direction in which the inner ring of the electrode assembly 13 is directed toward the outer ring, and the surfaces of the first tabs 131 are sector-shaped, or approximately sector-shaped.

In the above-mentioned technical solution, in some embodiments, the dimension of each second sub-tab 1320 in the winding direction of the electrode assembly 13 is set to the same dimension, so that the processing difficulty of the second sub-tab 1320 can be reduced (for example, when the tabs are die-cut, the die-cutting dimension of each second sub-tab 1320 is the same, so that the die-cutting efficiency is high), and the manufacturing efficiency of the battery 100 is improved. In some embodiments, by setting the size of the plurality of second sub-tabs 1320 in the winding direction of the electrode assembly 13 to be gradually increased in the direction in which the inner ring of the electrode assembly 13 is directed to the outer ring, the second tab 132 can be made to fully utilize the inner space of the case 11 such that the second tab 132 has a larger area to improve the overcurrent capability between the second tab 132 and the case 11, so that the battery 100 has superior charge and discharge performance.

According to some embodiments of the present application, referring to fig. 11, the first tab 131 has a first surface 1311 facing the first wall 110, and the first surface 1311 has a fan shape.

The first surface 1311 is a surface of the first tab 131 facing the first wall 110, and in some embodiments, the first surface 1311 is a surface of the first tab 131 that is electrically connected to the electrode terminal 12, e.g., the first surface 1311 is electrically connected to the electrode terminal 12 by being connected to the first adapter 14.

By "first surface 1311 is understood that first surface 1311 extends in a circular arc-like trajectory, for example, the end surface of electrode assembly 13 is circular, and first surface 1311 extends in the circumferential direction of the end surface of electrode assembly 13, forming a circular sector centered on the center of the end surface of electrode assembly 13.

The center of the fan-shaped first surface 1311 may be located on the central axis of the main body 130 or not located on the central axis of the main body 130.

In the above technical solution, by setting the first surface 1311 of the first tab 131 to a fan-shaped structure, the first tab 131 can fully utilize the inner space of the housing 11, so that the first tab 131 has a larger area to improve the overcurrent capability between the first tab 131 and the electrode terminal 12, and the battery 100 has better charge and discharge performance.

According to some embodiments of the application, along the circumferential direction y of the body portion, the first surface 1311 has a first edge 13110 and a second edge 13111 that are distant from each other, the angle between the first edge 13110 and the second edge 13111 being α1,0 < α1+.270 °.

In some embodiments, the arcuate trajectory of the first surface 1311 is parallel to the circumferential direction y of the body portion, and the corresponding center of the first surface 1311 may be located on the central axis of the body portion 130.

The first edge 13110 and the second edge 13111 are two edges of the first surface 1311 that are distant from each other on an arc-shaped trajectory thereof, and an angle between the first edge 13110 and the second edge 13111 may correspond to a central angle of the first surface 1311 in a fan shape.

In some embodiments, the angle α1 between the first edge 13110 and the second edge 13111 is less than or equal to 270 °, e.g., the angle α1 between the first edge 13110 and the second edge 13111 may be 1 °, 2 °, … °, 46 °, 47 °, … °, 91 °, 92 °, … 180 °, 181 °, 182 °, … °, 269 °, 270 °, or any value between two adjacent values.

In the above technical solution, by setting the angle α1 formed between the first edge 13110 and the second edge 13111 of the first tab 131 to be less than or equal to 270 degrees, the central angle of the first surface 1311 of the first tab 131 in the shape of a fan is less than or equal to 270 degrees, so as to alleviate the phenomenon that the first tab 131 and the second tab 132 overlap easily due to the excessively large space occupied by the first tab 131, thereby making the battery 100 have higher reliability.

According to some embodiments of the application, the second tab 132 has a second surface 1321 facing the first wall 110, the second surface 1321 being scalloped.

The second surface 1321 is a surface of the second tab 132 facing the first wall 110, and in some embodiments, the second surface 1321 is a surface of the second tab 132 that is electrically connected to the first wall 110, e.g., the second surface 1321 is electrically connected to the first wall 110 by being connected to the second adapter 15.

By "second surface 1321 is understood that second surface 1321 extends in an arc-shaped locus, for example, the end face of electrode assembly 13 is circular, and second surface 1321 extends in the circumferential direction of the end face of electrode assembly 13, forming a fan shape centered on the center of the end face of electrode assembly 13.

The center of the fan-shaped second surface 1321 may be located on the central axis of the main body 130 or may not be located on the central axis of the main body 130.

In the above technical solution, by setting the second surface 1321 of the second tab 132 to a fan-shaped structure, the second tab 132 can fully utilize the inner space of the housing 11, so that the second tab 132 has a larger area to improve the overcurrent capability between the second tab 132 and the housing 11, and the battery 100 has better charge and discharge performance.

According to some embodiments of the application, the second surface 1321 has a third edge 13210 and a fourth edge 13211, which are distant from each other, along the circumferential direction y of the main body portion, the angle between the third edge 13210 and the fourth edge 13211 being α2,0 < α2+.180 °.

In some embodiments, the arcuate trajectory of the second surface 1321 is parallel to the circumferential direction y of the body portion, and the corresponding center of the second surface 1321 may be located on the central axis of the body portion 130.

The third edge 13210 and the fourth edge 13211 are two edges of the third surface that are distant from each other on its arc-shaped trajectory, and the angle between the third edge 13210 and the fourth edge 13211 may correspond to the central angle of the second surface 1321 that is in the shape of a fan.

In some embodiments, the angle α2 between the third edge 13210 and the fourth edge 13211 is less than or equal to 180 °, e.g., the angle α2 between the third edge 13210 and the fourth edge 13211 may be 1 °, 2 °, … °, 46 °, 47 °, … °, 91 °, 92 °, … °, 179 °, 180 °, or any value between two adjacent values.

In the above technical solution, by setting the angle α2 formed between the third edge 13210 and the fourth edge 13211 of the second tab 132 to be less than or equal to 180 degrees, the central angle of the second surface 1321 of the second tab 132 in the shape of a fan is less than or equal to 180 degrees, so as to alleviate the phenomenon that the first tab 131 and the second tab 132 are easy to short due to the excessively large space occupied by the second tab 132, thereby making the battery 100 have higher reliability.

According to some embodiments of the present application, referring to fig. 7, the case 11 includes a case 112 and an end cap, the electrode assembly 13 is disposed inside the case 112, and the end cap closes an opening of the case 112. The first wall 110 is an end cap.

The first wall 110 is an end cap, which may be a separate structure from the housing 112, and the end cap may be connected to the housing 112 by welding, bonding, clamping, or other connecting means.

In the above technical solution, the first wall 110 of the housing 11 is configured as an end cover of the housing 11 for closing the opening of the casing 112, and the battery cell 10 adopting such a structure is convenient for assembling the electrode terminal 12 on the end cover, and can reduce the difficulty of electrically connecting the first tab 131 and the second tab 132 with the end cover and the electrode terminal 12, thereby reducing the manufacturing difficulty of the battery cell 10 and improving the manufacturing efficiency of the battery 100.

According to some embodiments of the application, the housing 11 is cylindrical or prismatic.

In the above technical scheme, the space utilization rate of the battery cells 10 can be improved by arranging the outer shell 11 to be a cylinder or a prism, and in the battery 100, two adjacent battery cells 10 can be closely arranged, thereby being beneficial to the improvement of the volume energy density of the battery 100.

According to some embodiments of the present application, the present application also provides a battery 100, the battery 100 including the battery cell 10 of any one of the above aspects.

As shown in fig. 2, the battery 100 may further include a case 20, and the battery cell 10 is accommodated in the case 20.

In some embodiments, the case 20 may include a first case body 21 and a second case body 22, the first case body 21 and the second case body 22 being overlapped with each other, the first case body 21 and the second case body 22 together defining an assembly space for accommodating the battery cell 10.

Alternatively, the second casing body 22 may have a hollow structure with one end opened, the first casing body 21 may have a plate-like structure, and the first casing body 21 covers the open side of the second casing body 22, so that the first casing body 21 and the second casing body 22 together define an assembly space; the first tank body 21 and the second tank body 22 may each have a hollow structure with one side opened, and the open side of the first tank body 21 may be closed to the open side of the second tank body 22.

Of course, the case 20 formed by the first case body 21 and the second case body 22 may be various shapes, such as a cylinder, a rectangular parallelepiped, or the like. Illustratively, in fig. 2, the housing 20 is of a rectangular parallelepiped configuration.

Alternatively, the number of the battery cells 10 disposed in the case 20 may be one or more. For example, in fig. 2, a plurality of battery cells 10 are disposed in a case 20 of the battery 100, and the plurality of battery cells 10 may be connected in series or parallel or in series-parallel, where a series-parallel refers to both of the plurality of battery cells 10. The plurality of battery cells 10 can be directly connected in series or in parallel or in series-parallel, and then the whole formed by the plurality of battery cells 10 is accommodated in the box body 20; of course, the battery 100 may also be a battery module formed by connecting a plurality of battery cells 10 in series or parallel or series-parallel connection, and a plurality of battery modules are then connected in series or parallel or series-parallel connection to form a whole and are accommodated in the case 20.

The battery 100 may further include other structures, for example, the battery 100 may further include a bus member connecting the plurality of battery cells 10 to achieve electrical connection between the plurality of battery cells 10.

It should be noted that, in some embodiments, the battery 100 may not include the case 20, the battery 100 includes a plurality of battery cells 10, and the battery 100 including the plurality of battery cells 10 may be directly assembled to the power device to provide the power to the power device through the plurality of battery cells 10. That is, the case 20 may be part of an electric device. For example, the electrical device may be a vehicle 1000, the housing 20 may be part of the chassis structure of the vehicle 1000, for example, a portion of the housing 20 may be at least part of the floor of the vehicle 1000, or a portion of the housing 20 may be at least part of the cross member and side members of the vehicle 1000.

According to some embodiments of the present application, there is also provided an electric device, including the battery cell 10 of any of the above aspects, and the battery cell 10 is used to provide electric energy for the electric device.

According to some embodiments of the present application, a battery cell 10 is provided, see fig. 3-9.

The battery cell 10 includes a case 11, an electrode terminal 12, an electrode assembly 13, a first adapter 14, a second adapter 15, and an insulator 16. The housing 11 has a cylindrical shape, and the housing 11 has a first wall 110 having a disk shape.

The electrode terminal 12 is provided on the first wall 110 in an insulating manner. The electrode assembly 13 is a roll-to-roll electrode assembly.

The electrode assembly 13 is accommodated in the case 11, and the electrode assembly 13 includes a body part 130, a first tab 131 and a second tab 132, the polarities of the first tab 131 and the second tab 132 being opposite, the body part 130 having a central through hole 1300, the central through hole 1300 penetrating the body part 130 in an axial direction of the body part 130. The first tab 131 and the second tab 132 are disposed at one end of the main body 130 near the first wall 110, the first tab 131 is electrically connected to the electrode terminal 12 through the first adapter 14, and the second tab 132 is electrically connected to the first wall 110 through the second adapter 15.

The central axis of the electrode terminal 12 is deviated from the central axis of the battery cell 10, that is, the electrode terminal 12 is eccentrically arranged on the first wall 110, so that the electrode terminal 12 (or the position where the electrode terminal 12 is electrically connected with the first tab 131) is far away from the second tab 132 (or the position where the second tab 132 is electrically connected with the first wall 110), and therefore, the risk of the overlap joint of the positive electrode and the negative electrode of the battery cell 10 and the internal short circuit of the battery cell 10 can be reduced; on the other hand, the current transmission path between the electrode terminal 12 and the first tab 131 can be reduced, so that the current output or input capability of the battery cell 10 can be improved, and the battery 100 has high reliability.

Along the thickness direction x of the first wall, the orthographic projection of the electrode terminal 12 falls entirely within the orthographic projection of the first tab 131. Wherein the distance from the central axis of the electrode terminal 12 to the central axis of the battery cell 10 is h, and the radius of the first wall 110 is r, r/5.ltoreq.h. In some embodiments, the distance h from the central axis of the electrode terminal 12 to the central axis of the battery cell 10 is 3mm or more.

In some embodiments, the first wall 110 is provided with a liquid injection hole 1100, and the insulating member 16 is provided with a first through hole, and the liquid injection hole 1100 is at least partially opposite to the first through hole along the thickness direction x of the first wall, and the first through hole is at least partially opposite to the central through hole 1300. Electrolyte can be injected into the housing 11 through the injection hole 1100, and flows into the central through hole 1300 through the first through hole, so that the electrolyte can infiltrate the electrode assembly 13.

The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A battery cell, comprising:

a housing having a first wall;

an electrode terminal provided on the first wall in an insulating manner;

the electrode assembly is accommodated in the shell and comprises a main body part, a first tab and a second tab, the polarities of the first tab and the second tab are opposite, the first tab and the second tab are arranged at one end, close to the first wall, of the main body part, the first tab is electrically connected with the electrode terminal, and the second tab is electrically connected with the first wall;

the central axis of the electrode terminal deviates from the central axis of the battery cell, and the orthographic projection of the electrode terminal falls into the orthographic projection of the first tab along the thickness direction of the first wall.

2. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

The electrode assembly is a winding electrode assembly, the main body part is provided with a central through hole, and the central through hole penetrates through the main body part along the axial direction of the main body part;

in the thickness direction of the first wall, the orthographic projection of the electrode terminal does not overlap with the center through hole.

3. The battery cell of claim 2, wherein the battery cell comprises a plurality of cells,

the first wall is provided with a liquid injection hole, and the liquid injection hole is at least partially opposite to the central through hole along the thickness direction of the first wall.

4. The battery cell of claim 3, wherein the battery cell comprises a plurality of cells,

the central axis of the liquid injection hole coincides with the central axis of the battery monomer.

5. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the distance from the central axis of the electrode terminal to the central axis of the battery cell is h; along the direction orthogonal to the central axis of the battery cell, the maximum distance from the edge of the first wall to the central axis of the battery cell is r, and r/5 is less than or equal to h and less than r.

6. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the distance from the central axis of the electrode terminal to the central axis of the battery cell is h, and h is more than or equal to 3mm.

7. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

and along the thickness direction of the first wall, the orthographic projection area of the electrode terminal is S1, and the orthographic projection area of the first wall is S, so that S is more than or equal to 5% and less than or equal to 50% and S is more than or equal to 5%.

8. The battery cell of claim 1, wherein the battery cell further comprises:

a first adapter connecting the first tab and the electrode terminal;

and the second adapter is connected with the second lug and the first wall.

9. The battery cell of claim 8, wherein the battery cell comprises a plurality of cells,

the orthographic projection of the first adapter does not overlap with the central through hole along the thickness direction of the first wall.

10. The battery cell of claim 9, wherein the battery cell further comprises:

and an insulating member disposed between the electrode assembly and the first wall, the insulating member insulating and isolating the first and second switching members.

11. The battery cell of claim 10, wherein the battery cell comprises a plurality of cells,

the first wall is provided with a liquid injection hole, the insulating piece is provided with a first through hole, the liquid injection hole is at least partially opposite to the first through hole along the thickness direction of the first wall, and the first through hole is at least partially opposite to the central through hole.

12. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the minimum distance between the first lug and the second lug is L, and the diameter of the central through hole is D, so that the L is more than or equal to D.

13. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the first tab is a positive tab; or, the first tab is a negative tab.

14. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the battery monomer is a sodium ion battery monomer or a lithium ion battery monomer.

15. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the electrode assembly comprises a first pole piece and a second pole piece, and is a winding type electrode assembly;

The first pole piece comprises a plurality of first sub-pole lugs, the first pole lugs are formed by the plurality of first sub-pole lugs, the first sub-pole lugs are not arranged on the first pole piece of the innermost n1 circles, and n1 is more than or equal to 1; and/or

The second pole piece comprises a plurality of second sub-pole lugs, the second pole lugs are formed by the second sub-pole lugs, the second sub-pole lugs are not arranged on the second pole piece of the innermost n2 circles, and n2 is more than or equal to 1.

16. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the first pole piece comprises a plurality of first sub-pole lugs, the first pole lugs are formed by the plurality of first sub-pole lugs, the first sub-pole lugs are not arranged on the first pole piece of the outermost m1 circles, and m1 is more than or equal to 1; and/or

The second pole piece comprises a plurality of second sub-pole lugs, the second pole lugs are formed by the second sub-pole lugs, the second pole piece of the outermost m2 circles is not provided with the second sub-pole lugs, and m2 is more than or equal to 1.

17. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the electrode assembly is a winding type electrode assembly, the first tab comprises a plurality of first sub-tabs, and the size of each first sub-tab in the winding direction of the electrode assembly is the same; or (b)

The first sub-tabs gradually increase in size in a winding direction of the electrode assembly along a direction in which an inner ring of the electrode assembly is directed to an outer ring.

18. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the electrode assembly is a winding type electrode assembly, the second tab comprises a plurality of second sub-tabs, and the size of each second sub-tab in the winding direction of the electrode assembly is the same; or (b)

The size of the plurality of second sub-tabs in the winding direction of the electrode assembly gradually increases along a direction in which the inner ring of the electrode assembly is directed to the outer ring.

19. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the first tab has a first surface facing the first wall, the first surface being scalloped.

20. The battery cell of claim 19, wherein the cell comprises a plurality of cells,

the first surface is provided with a first edge and a second edge which are far away from each other along the circumferential direction of the main body part, and the angle between the first edge and the second edge is alpha 1, and alpha 1 is more than 0 and less than or equal to 270 degrees.

21. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the second tab has a second surface facing the first wall, the second surface being scalloped.

22. The battery cell of claim 21, wherein the cell comprises a plurality of cells,

the second surface is provided with a third edge and a fourth edge which are far away from each other along the circumferential direction of the main body part, and the angle between the third edge and the fourth edge is alpha 2, and alpha 2 is more than 0 and less than or equal to 180 degrees.

23. The battery cell of any one of claims 1-22, wherein the cell comprises a plurality of cells,

the casing comprises a shell and an end cover, the electrode assembly is arranged in the shell, and the end cover closes the opening of the shell;

the first wall is the end cap.

24. The battery cell of claim 1, wherein the battery cell comprises a plurality of cells,

the shell is a cylinder or a prism.

25. A battery comprising a cell according to any one of claims 1-24.

26. An electrical device comprising a cell according to any one of claims 1 to 24 for providing electrical energy.