Battery cell and electric equipment

Abstract

The invention provides a battery cell and electric equipment, an electrode assembly of the battery cell comprises a first pole piece group and a second pole piece group, and the length of the first pole piece group along a second direction is smaller than that of the second pole piece group along the second direction; the first pole piece group comprises a first pole piece and a second pole piece which are opposite in polarity, the first empty foil area of each first pole piece is at least partially overlapped with the second notch of the second pole piece, and the second empty foil area of each second pole piece is at least partially overlapped with the first notch of the first pole piece; the second pole piece group comprises third pole pieces and fourth pole pieces which are opposite in polarity, a third empty foil area of each third pole piece is at least partially overlapped with a fourth notch of the fourth pole piece, and a fourth empty foil area of each fourth pole piece is at least partially overlapped with a third notch of the third pole piece; the first pole piece and the third pole piece have the same polarity, at least part of the first empty foil area is overlapped with the third empty foil area, and at least part of the second empty foil area is overlapped with the fourth empty foil area. And the energy density of the battery cell can be improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a battery cell and an electrical device. Background Art

[0002] With the rapid development of new energy technologies, batteries have been widely used in electronic equipment, electric vehicles, electric two-wheelers, power tools, etc. The requirements for battery quality, safety, and miniaturization are becoming increasingly higher.

[0003] The electrical connector connected to the electrode tab of the electrode assembly generally extends out of the casing in the length direction or width direction of the electrode assembly, so that a large space needs to be reserved between the casing and one end of the electrode assembly where the electrical connector is set to accommodate the tab and the electrical connector, which affects the energy density of the battery. Summary of the invention

[0004] The present application provides a battery cell and an electrical device, which can improve the energy density of the battery cell.

[0005] In a first aspect, the present application provides a battery cell, the battery cell comprising a housing and an electrode assembly, the electrode assembly being accommodated in the housing. The electrode assembly comprises a first electrode sheet group and a second electrode sheet group stacked along a first direction, the length of the first electrode sheet group along the second direction being less than the length of the second electrode sheet group along the second direction, and the first direction is perpendicular to the second direction. The first electrode sheet group comprises a first electrode sheet and a second electrode sheet stacked along the first direction and having opposite polarities. Each first electrode sheet has a first notch. Each second electrode sheet has a second notch. When viewed along the first direction, the first notch and the second notch do not overlap. Each first electrode sheet has a first empty foil area that at least partially overlaps with the second notch, and each second electrode sheet has a second empty foil area that at least partially overlaps with the first notch. The second electrode sheet group comprises a third electrode sheet and a fourth electrode sheet stacked along the first direction and having opposite polarities. Each third electrode sheet has a third notch. Each fourth electrode sheet has a fourth notch. When viewed along the first direction, the third notch and the fourth notch do not overlap. Each third electrode sheet has a third empty foil area that at least partially overlaps with the fourth notch. Each fourth electrode sheet has a fourth empty foil area that at least partially overlaps with the third notch. The first pole piece and the third pole piece have the same polarity. When viewed along the first direction, at least a portion of the first empty foil area overlaps with the third empty foil area, and at least a portion of the second empty foil area overlaps with the fourth empty foil area.

[0006] In the above technical solution, the electrode assembly is accommodated in the shell, so that the shell can protect the electrode assembly; the electrode assembly includes a first electrode plate group and a second electrode plate group stacked along a first direction, the length of the first electrode plate group along the second direction is less than the length of the second electrode plate group along the second direction, and the first direction is perpendicular to the second direction, so that the electrode assembly can form a step, which can be used to accommodate other components when the battery cell is assembled in an electrical device; the first electrode plate group includes a first electrode plate and a second electrode plate with opposite polarities stacked along the first direction, each first electrode plate has a first notch, each second electrode plate has a second notch, and when viewed along the first direction, the first notch and the second notch do not overlap; each first electrode plate A first empty foil area at least partially overlaps with the second notch, and each second electrode sheet has a second empty foil area at least partially overlaps with the first notch, so that the first empty foil area and the second empty foil area are spaced apart on a vertical plane in the first direction, which can reduce the possibility of the first empty foil area and the second empty foil area contacting and short-circuiting, and can reduce the volume of the first empty foil area protruding from the first electrode sheet, and reduce the volume of the second empty foil area protruding from the second electrode sheet. The spacing space reserved between the electrode assembly and the shell for accommodating the first empty foil area and the second empty foil area is small, which can improve the energy density of the battery cell, and when the battery cell is subjected to external force, the possibility of the electrode assembly shaking relative to the shell is small, so that the first empty foil area and the second electrode sheet, and the second empty foil area and the first electrode sheet contacting and short-circuiting are less likely to occur. The possibility is small, thereby reducing the risk of thermal runaway of the battery cell; by making the second pole piece group include a third pole piece and a fourth pole piece stacked along the first direction and with opposite polarities, each third pole piece has a third notch, each fourth pole piece has a fourth notch, and when viewed along the first direction, the third notch and the fourth notch do not overlap; each third pole piece has a third empty foil area that at least partially overlaps with the fourth notch, and each fourth pole piece has a fourth empty foil area that at least partially overlaps with the third notch, so that the third empty foil area and the fourth empty foil area are spaced apart on a vertical plane in the first direction, which can reduce the possibility of short circuit between the third empty foil area and the fourth empty foil area, and can reduce the volume of the third empty foil area protruding from the third pole piece, and reduce the protrusion of the fourth empty foil area from the third The volume of the quadrupole sheet and the interval space reserved between the electrode assembly and the shell for accommodating the third empty foil area and the fourth empty foil area are small, which can improve the energy density of the battery cell, and when the battery cell is subjected to external force, the electrode assembly is less likely to shake relative to the shell, making it less likely that the third empty foil area will contact and short-circuit with the fourth electrode sheet, and the fourth empty foil area will contact and short-circuit with the third electrode sheet, thereby reducing the risk of thermal runaway of the battery cell; by making the first electrode sheet and the third electrode sheet have the same polarity, when observed along the first direction, at least part of the first empty foil area overlaps with the third empty foil area, and at least part of the second empty foil area overlaps with the fourth empty foil area, which can facilitate the first empty foil area to be connected to the third empty foil area and lead out of the shell, and facilitate the second empty foil area to be connected to the fourth empty foil area and lead out of the shell.

[0007] In some embodiments of the present application, the first empty foil area and the second empty foil area are located at one end of the first electrode group along the third direction. The third empty foil area and the fourth empty foil area are located at one end of the second electrode group along the third direction. The first direction, the second direction, and the third direction are perpendicular to each other.

[0008] In the above technical solution, by making the first empty foil area and the second empty foil area located at one end of the first electrode group along the third direction, and the third empty foil area and the fourth empty foil area located at one end of the second electrode group along the third direction, only one side of the spacing space between the housing and the electrode assembly is reserved for accommodating the first empty foil area, the second empty foil area, the third empty foil area and the fourth empty foil area, the energy density of the battery cell can be further improved.

[0009] In some embodiments of the present application, the first pole piece has a first coating area, and along the second direction, a portion of the first coating area is located between the first notch and the first empty foil area. The second pole piece has a second coating area, and along the second direction, a portion of the second coating area is located between the second notch and the second empty foil area.

[0010] In the above technical solution, due to the steps of the battery cell, the sizes of the first electrode group and the second electrode group are different, and the first empty foil area and the second empty foil area are located on the overlapping side of the first electrode group and the second electrode group, which will cause uneven distribution of internal force when the battery cell is subjected to force, and there is a risk of damage or even breakage of the first empty foil area and the second empty foil area. By making a part of the first coated area between the first notch and the first empty foil area and a part of the second coated area between the second notch and the second empty foil area along the second direction, the internal force distribution when the battery cell is subjected to force can be made more uniform, reducing the risk of damage or even breakage of the first empty foil area and the second empty foil area, thereby protecting the first empty foil area and the second empty foil area.

[0011] In some embodiments of the present application, the first notch and the first empty foil area are respectively located at two corners of the first pole piece; the second notch and the second empty foil area are respectively located at two corners of the second pole piece.

[0012] In the above technical solution, by making the first notch and the first empty foil area respectively located at two corners of the first pole piece, and the second notch and the second empty foil area respectively located at two corners of the second pole piece, it is possible to facilitate the preparation of the first notch, the first empty foil area, the second notch and the second empty foil area, and facilitate the lead-out of the first empty foil area and the second empty foil area, further reducing the possibility of short circuit between the first empty foil area and the second pole piece, and between the second empty foil area and the first pole piece.

[0013] In some embodiments of the present application, the third pole piece has a third coating area, and along the second direction, a portion of the third coating area is located between the third notch and the third empty foil area; the fourth pole piece has a fourth coating area, and along the second direction, a portion of the fourth coating area is located between the fourth notch and the fourth empty foil area.

[0014] In the above technical solution, due to the steps of the battery cell, the sizes of the first electrode group and the second electrode group are different, and the third empty foil area and the fourth empty foil area are located on the overlapping side of the first electrode group and the second electrode group, which will cause uneven distribution of internal force when the battery cell is subjected to force, and the third empty foil area and the fourth empty foil area are at risk of damage or even breakage. By making a part of the third coating area located between the third notch and the third empty foil area, and a part of the fourth coating area located between the fourth notch and the fourth empty foil area along the second direction, the internal force distribution can be made more uniform when the battery cell is subjected to force, reducing the risk of damage or even breakage of the third empty foil area and the fourth empty foil area, thereby protecting the third empty foil area and the fourth empty foil area.

[0015] In some embodiments of the present application, the third notch and the third empty foil area are respectively located at two corners of the third pole piece; the fourth notch is located at a corner of the fourth pole piece, the fourth pole piece has a first edge and a second edge opposite to each other along the second direction, and the first edge and the fourth notch are located on the same side of the fourth pole piece; along the second direction, the distance between the fourth empty foil area and the second edge is D1, the width of the second pole piece is W1, and the width of the fourth pole piece is W2, satisfying 0≤D1-(W2-W1)≤6mm. In the above technical solution, by making the third notch and the third empty foil area respectively located at two corners of the third pole piece, and the fourth notch located at one corner of the fourth pole piece, it is possible to facilitate the preparation of the third notch, the third empty foil area, and the fourth notch, and to facilitate the lead-out of the third empty foil area; when D1-(W2-W1) is greater than or equal to 0, the second empty foil area can overlap with the fourth empty foil area in the first direction, thereby facilitating the connection and lead-out of the second empty foil area and the fourth empty foil area; when D1-(W2-W1) is greater than 6mm, the distance between the third empty foil area and the fourth empty foil area is small, which may cause the risk of contact between the third empty foil area and the fourth empty foil area during use; therefore, when 0≤D1-(W2-W1)≤6mm, it is possible to facilitate the connection and lead-out of the second empty foil area and the fourth empty foil area, and to improve the safety performance of the battery cell.

[0016] In some embodiments of the present application, 0≤D1-(W2-W1)≤2mm.

[0017] In the above technical scheme, when D1-(W2-W1) is greater than or equal to 0, the second empty foil area can overlap with the fourth empty foil area in the first direction, thereby facilitating the connection and lead-out of the second empty foil area and the fourth empty foil area; when D1-(W2-W1) is less than or equal to 2 mm, the distance between the third empty foil area and the fourth empty foil area is further maintained at a large distance; therefore, when 0≤D1-(W2-W1)≤2 mm, it can not only facilitate the connection and lead-out of the second empty foil area and the fourth empty foil area, but also be beneficial to further improve the safety performance of the battery cell.

[0018] In some embodiments of the present application, along the second direction, the width of the second pole piece is W1, and the width of the fourth pole piece is W2, satisfying 1mm≤W2-W1≤3 / 4*W2.

[0019] In the above technical scheme, when W2-W1 is greater than or equal to 1mm, the step formed by the battery cell can be used to accommodate other components; when W2-W1 is less than or equal to 3 / 4*W2, the width of the coated area of ​​each electrode between the notch and the empty foil area is larger, which is beneficial to improve the energy density of the battery cell and can reduce the risk of pressing the battery cell during the formation process; therefore, when 1mm≤W2-W1≤3 / 4*W2, it can facilitate the step formed by the battery cell to accommodate other components, and can also help improve the energy density of the battery cell and reduce the risk of pressing the battery cell during the formation process.

[0020] In some embodiments of the present application, 1mm≤W2-W1≤1 / 2*W2.

[0021] In the above technical scheme, when W2-W1 is greater than or equal to 1mm, the step formed by the battery cell can be used to accommodate other components; when W2-W1 is less than or equal to 1 / 2*W2, the width of the coated area of ​​each electrode between the notch and the empty foil area is further made larger, which is beneficial to further improve the energy density of the battery cell and can further reduce the risk of pressing the battery cell during the formation process; therefore, when 1mm≤W2-W1≤3 / 4*W2, it can facilitate the step formed by the battery cell to accommodate other components, and can also help to further improve the energy density of the battery cell and can further reduce the risk of pressing the battery cell during the formation process.

[0022] In some embodiments of the present application, the third empty foil area is located at a corner of the third pole piece, the third pole piece includes a third coating area, and the third coating area is arranged on both sides of the third notch along the second direction; the fourth notch is located at a corner of the fourth pole piece, the fourth pole piece includes a fourth coating area, and the fourth coating area is arranged on both sides of the third notch along the second direction.

[0023] In the above technical scheme, by locating the third empty foil area at a corner of the third pole piece and the fourth notch at a corner of the fourth pole piece, the preparation of the third empty foil area and the fourth notch can be facilitated; due to the steps of the battery cell, the sizes of the first pole piece group and the second pole piece group are different, and the third empty foil area and the fourth empty foil area are located on the overlapping side of the first pole piece group and the second pole piece group, which will cause uneven distribution of internal force when the battery cell is subjected to force, and the third empty foil area and the fourth empty foil area are at risk of damage or even breakage. By providing the third coating area on both sides of the third notch and the fourth coating area on both sides of the third notch along the second direction, the internal force distribution when the battery cell is subjected to force can be made more uniform, reducing the risk of damage or even breakage of the third empty foil area and the fourth empty foil area, thereby protecting the third empty foil area and the fourth empty foil area.

[0024] In some embodiments of the present application, the first pole piece group has a first end and a second end opposite to each other along the second direction, and the second pole piece group has a third end and a fourth end opposite to each other along the second direction, the first end is flush with the third end, and the fourth end exceeds the second end.

[0025] In the above technical solution, by making the first electrode plate group have a first end and a second end opposite to each other along the second direction, and the second electrode plate group have a third end and a fourth end opposite to each other along the second direction, the first end is flush with the third end, and the fourth end exceeds the second end, the assembly of the first electrode plate group and the second electrode plate group can be facilitated, and a step is formed on one side of the battery cell along the second direction, so as to facilitate the accommodation of components of the electrical equipment.

[0026] In some embodiments of the present application, the first empty foil area and the second empty foil area are located at one end of the first pole piece group along the second direction, and the second pole piece group exceeds the other end of the first pole piece group along the second direction; the third empty foil area and the fourth empty foil area are located at one end of the second pole piece group along the second direction.

[0027] In the above technical solution, by locating the first empty foil area and the second empty foil area at one end of the first electrode sheet group along the second direction, and locating the third empty foil area and the fourth empty foil area at one end of the second electrode sheet group along the second direction, the first empty foil area and the third empty foil area can be connected and led out at one end of the electrode assembly along the second direction, and the second empty foil area and the fourth empty foil area can be connected and led out at one end of the electrode assembly along the second direction; by making the second electrode sheet group extend beyond the other end of the first electrode sheet group along the second direction, a step can be formed at the other end of the battery cell along the second direction, so as to facilitate the accommodation of components of electrical equipment.

[0028] In some embodiments of the present application, the third notch and the third empty foil area are respectively located at two corners of the third pole piece, the third pole piece has a third coating area, and along the third direction, a portion of the third coating area is located between the third notch and the third empty foil area; the fourth notch and the fourth empty foil area are respectively located at two corners of the fourth pole piece, the fourth pole piece has a fourth coating area, and along the third direction, a portion of the fourth coating area is located between the fourth notch and the fourth empty foil area; the first direction, the second direction and the third direction are perpendicular to each other.

[0029] In the above technical solution, by making the third notch and the third empty foil area respectively located at two corners of the third pole piece, and the fourth notch and the fourth empty foil area respectively located at two corners of the fourth pole piece, it is easy to prepare the third empty foil area, the third notch, the fourth empty foil area and the fourth notch, and the first pole piece group, the second pole piece group, the first empty foil area and the second empty foil area, the third empty foil area and the fourth empty foil area are symmetrically arranged relative to the central axis of the battery cell along the second direction, so that when the battery cell is subjected to force, the internal force distribution is more uniform, and the possibility of damage to the inside of the battery cell is lower; due to the steps of the battery cell, the first pole piece group and the second pole piece group The sizes are different, and the third empty foil area and the fourth empty foil area are located on the overlapping side of the first pole piece group and the second pole piece group, which will cause the internal force distribution to be still uneven when the battery cell is subjected to force, and the third empty foil area and the fourth empty foil area are at risk of being damaged or even broken. By making a part of the third coated area between the third notch and the third empty foil area, and a part of the fourth coated area between the fourth notch and the fourth empty foil area along the third direction, the internal force distribution can be made more uniform when the battery cell is subjected to force, reducing the risk of damage or even breakage of the third empty foil area and the fourth empty foil area, thereby protecting the third empty foil area and the fourth empty foil area.

[0030] In some embodiments of the present application, the first pole piece is a positive pole piece, and the second pole piece is a negative pole piece; the spacing distance between the end of the second pole piece provided with the second empty foil area and the outer shell is D2, satisfying 0.4mm≤D2≤0.5mm.

[0031] In the above technical scheme, since the size of the negative electrode plate is generally larger than that of the positive electrode plate, the spacing distance between the negative electrode plate and the outer shell is the spacing distance between the electrode assembly and the outer shell; by making the spacing distance D2 between the end of the second electrode plate provided with the second empty foil area and the outer shell satisfy 0.4mm≤D2≤0.5mm, it can further facilitate the assembly of the electrode assembly and the outer shell, and accommodate the electrolyte, and can also further make the energy density of the battery cell higher; and if no notch is provided in the battery cell to accommodate the empty foil area, the empty foil area protrudes and occupies the space between the outer shell and the electrode assembly, affecting the energy density of the battery cell. In this scheme, a notch is provided in the electrode plate to accommodate the empty foil area, so that the distance between the end of the second electrode plate provided with the second empty foil area and the inner wall of the outer shell can be limited to within the above range.

[0032] In some embodiments of the present application, the battery cell includes a first electrical connector and a second electrical connector, the first electrical connector and the second electrical connector are located on the same side of the electrode assembly, the first electrical connector is connected to the first empty foil area and the third empty foil area, and the second electrical connector is connected to the second empty foil area and the fourth empty foil area; the outer shell includes a main body and a sealing part, the sealing part includes a top sealing part and a side sealing part, the top sealing part is located between the first electrical connector and the second electrical connector, and the top sealing part is bent toward the main body.

[0033] In the above technical solution, the battery cell includes a first electrical connector and a second electrical connector, the first electrical connector and the second electrical connector are located on the same side of the electrode assembly, the first electrical connector is connected to the first empty foil area and the third empty foil area, and the second electrical connector is connected to the second empty foil area and the fourth empty foil area, so that the load can be electrically connected to the battery cell through the first electrical connector and the second electrical connector; if no notch is provided in the battery cell to accommodate the empty foil area, the empty foil area protrudes, and the first electrical connector and the second electrical connector connected to the empty foil area extend from the top seal portion of the outer shell, and the top seal portion extends in a straight line and cannot be bent, resulting in a larger size of the battery cell along the direction in which the first electrical connector extends out of the sealing portion, affecting the energy density of the battery cell. Therefore, by making the empty foil areas of the battery cell all located in the notch, the top seal portion located between the first electrical connector and the second electrical connector protrudes from other parts of the sealing portion, and the top seal portion is bent toward the main body, so that the size of the battery cell along the direction in which the first electrical connector extends out of the sealing portion can be smaller, which is beneficial to improving the energy density of the battery cell.

[0034] In some embodiments of the present application, along the direction in which the first electrical connector extends out of the housing, a distance S from a surface of the first sealing portion facing away from the main body to a surface of the main body facing the first sealing portion satisfies 0.2mm≤S≤0.5mm.

[0035] In the above technical scheme, when S is greater than or equal to 0.2mm, the thickness of the first sealing portion is relatively large, so that the sealing effect of the first sealing portion is better, the battery cell is not prone to damage, leakage, etc., and the battery cell is safer; when S is less than or equal to 0.5mm, the dimension of the first sealing portion in the direction where the first electrical connector extends out of the top sealing portion is smaller, so that the dimension of the battery cell along the direction where the first electrical connector extends out of the sealing portion is smaller, which is beneficial to improving the energy density of the battery cell; therefore, when 0.2mm≤S≤0.5mm, it can not only make the sealing effect of the first sealing portion better, the battery cell is not prone to damage, leakage, etc., the battery cell is safer, but also can be beneficial to improving the energy density of the battery cell.

[0036] In a second aspect, the present application provides an electrical device, comprising a battery cell as described above, wherein the battery cell is used to provide electrical energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can also be obtained based on these drawings.

[0038] Figure 1 A schematic diagram of a three-dimensional structure of a battery cell provided in some embodiments of the present application;

[0039] Figure 2 A schematic diagram of the three-dimensional structure of an electrode assembly of a battery cell provided in some embodiments of the present application;

[0040] Figure 3 A schematic structural diagram of a first pole piece and a second pole piece of a battery cell provided in some embodiments of the present application from one perspective;

[0041] Figure 4 A schematic structural diagram of a third pole piece and a fourth pole piece of a battery cell provided in some embodiments of the present application from one perspective;

[0042] Figure 5 A schematic diagram of a three-dimensional structure of a battery cell provided in some other embodiments of the present application;

[0043] Figure 6 A schematic diagram of the three-dimensional structure of an electrode assembly of a battery cell provided in some other embodiments of the present application;

[0044] Figure 7 A schematic structural diagram of a third pole piece and a fourth pole piece of a battery cell provided in some other embodiments of the present application from one perspective;

[0045] Figure 8 A schematic diagram of a three-dimensional structure of a battery cell provided in some other embodiments of the present application;

[0046] Fig. 9 A schematic diagram of the three-dimensional structure of an electrode assembly of a battery cell provided in some other embodiments of the present application;

[0047] Fig.10 A schematic structural diagram of a first pole piece and a second pole piece of a battery cell provided in some other embodiments of the present application from one perspective;

[0048] Fig.11 A schematic structural diagram of a third pole piece and a fourth pole piece of a battery cell provided in some other embodiments of the present application from one perspective;

[0049] Fig.12 A schematic structural diagram of a battery cell from one perspective provided in some embodiments of the present application;

[0050] Fig.13 for Fig.12A schematic diagram of a partially enlarged cross-sectional view of the battery cell along the AA direction;

[0051] Fig.14 A schematic structural diagram of an electrode assembly of a battery cell provided in some other embodiments of the present application from one perspective;

[0052] Fig.15 A schematic structural diagram of an electrode assembly of a battery cell provided in some other embodiments of the present application from one perspective;

[0053] Fig.16 A schematic structural diagram of an electrode assembly of a battery cell provided in some other embodiments of the present application from one perspective;

[0054] Fig.17 A schematic structural diagram of an electrode assembly of a battery cell from one perspective provided in some other embodiments of the present application.

[0055] Icon: 10-battery cell; 100-housing; 110-main body; 120-sealing part; 121-first sealing part; 200-electrode assembly; 210-first electrode group; 211-first electrode; 2111-first notch; 2112-first empty foil area; 2113-first coating area; 212-second electrode; 2121-second notch; 2122-second empty foil area; 2123-second coating area; 220-second electrode group; 221-third electrode; 2211-third notch; 2212-third empty foil area; 2213-third coating area; 222-fourth electrode; 2221-fourth notch; 2222-fourth empty foil area; 2223-fourth coating area; 230-third electrode group; 310-first electrical connector; 320-second electrical connector; X-first direction; Y-second direction; Z-third direction. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of this application.

[0057] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as those commonly understood by technicians in the technical field to which this application belongs; the terms used in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0058] The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary and secondary relationship.

[0059] Reference to "embodiment" in this application means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments.

[0060] In the embodiments of the present application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components are omitted in different embodiments. It should be understood that the thickness, length, width and other dimensions of various components in the embodiments of the present application shown in the drawings, as well as the overall thickness, length, width and other dimensions of the integrated device are only exemplary descriptions and should not constitute any limitation to the present application.

[0061] With the development of the new energy industry, batteries are gradually developing towards high energy density, high power density and multi-function. In some electrical equipment, it is necessary to adapt to special-shaped battery cells. For example, electrical equipment with folding screens needs to adapt to battery cells with stepped surfaces so that components such as circuit boards can be set at the stepped parts of the battery cells.

[0062] For batteries with a step shape, the electrical connector connected to the pole ear of the electrode assembly generally extends out of the shell in the length direction or width direction of the electrode assembly, so that a large space needs to be reserved between the shell and one end of the electrode assembly where the electrical connector is set to accommodate the pole ear and the electrical connector, resulting in the space in the shell for accommodating the pole piece being compressed, affecting the energy density of the battery cell. In addition, due to the large spacing between the electrode assembly and the shell, the battery cell is prone to shaking relative to the shell when subjected to external force, while the electrical connector is fixed relative to the shell, which may cause the electrical connector to move relative to the pole piece, and then short-circuit with the pole piece, resulting in an increased risk of thermal runaway of the battery cell.

[0063] In order to improve the energy density of a battery cell, the present application provides a battery cell, the battery cell comprises a shell and an electrode assembly, the electrode assembly is accommodated in the shell; the electrode assembly comprises a first electrode sheet group and a second electrode sheet group stacked along a first direction, the length of the first electrode sheet group along the second direction is less than the length of the second electrode sheet group along the second direction, and the first direction is perpendicular to the second direction; the first electrode sheet group comprises a first electrode sheet and a second electrode sheet stacked along the first direction and having opposite polarities, each first electrode sheet has a first notch, each second electrode sheet has a second notch, and when viewed along the first direction, the first notch and the second notch do not overlap; each first electrode sheet has a first empty foil area that at least partially overlaps with the second notch , each second pole piece has a second empty foil area that at least partially overlaps with the first notch; the second pole piece group includes a third pole piece and a fourth pole piece that are stacked along the first direction and have opposite polarities, each third pole piece has a third notch, each fourth pole piece has a fourth notch, and when viewed along the first direction, the third notch and the fourth notch do not overlap; each third pole piece has a third empty foil area that at least partially overlaps with the fourth notch, and each fourth pole piece has a fourth empty foil area that at least partially overlaps with the third notch; the first pole piece and the third pole piece have the same polarity, and when viewed along the first direction, at least part of the first empty foil area overlaps with the third empty foil area, and at least part of the second empty foil area overlaps with the fourth empty foil area.

[0064] In a battery cell shell of this structure, the electrode assembly is accommodated in the shell, so that the shell can protect the electrode assembly; the electrode assembly includes a first electrode plate group and a second electrode plate group stacked along a first direction, the length of the first electrode plate group along the second direction is less than the length of the second electrode plate group along the second direction, and the first direction is perpendicular to the second direction, so that the electrode assembly can form a step, which can be used to accommodate other components when the battery cell is assembled in an electrical device; the first electrode plate group includes a first electrode plate and a second electrode plate with opposite polarities stacked along the first direction, each first electrode plate has a first notch, each second electrode plate has a second notch, and when viewed along the first direction, the first notch and the second notch do not overlap; each first The electrode piece has a first empty foil area that at least partially overlaps with the second notch, and each second electrode piece has a second empty foil area that at least partially overlaps with the first notch, so that the first empty foil area and the second empty foil area are spaced apart on a vertical plane in the first direction, which can reduce the possibility of the first empty foil area and the second empty foil area contacting and short-circuiting, and can reduce the volume of the first empty foil area protruding from the first electrode piece, and reduce the volume of the second empty foil area protruding from the second electrode piece. The spacing space reserved between the electrode assembly and the shell for accommodating the first empty foil area and the second empty foil area is small, which can improve the energy density of the battery cell, and when the battery cell is subjected to an external force, the possibility of the electrode assembly shaking relative to the shell is small, so that the first empty foil area and the second electrode piece, and the second empty foil area and the first electrode piece contact and short-circuit. The possibility of short circuit is small, thereby reducing the risk of thermal runaway of the battery cell; by making the second pole piece group include a third pole piece and a fourth pole piece stacked along the first direction and having opposite polarities, each third pole piece has a third notch, each fourth pole piece has a fourth notch, and when viewed along the first direction, the third notch and the fourth notch do not overlap; each third pole piece has a third empty foil area that at least partially overlaps with the fourth notch, and each fourth pole piece has a fourth empty foil area that at least partially overlaps with the third notch, so that the third empty foil area and the fourth empty foil area are spaced apart on a vertical plane in the first direction, which can reduce the possibility of short circuit between the third empty foil area and the fourth empty foil area, and can reduce the volume of the third empty foil area protruding from the third pole piece, and reduce the protrusion of the fourth empty foil area from the third pole piece. The volume of the fourth pole piece and the interval space reserved between the electrode assembly and the shell for accommodating the third empty foil area and the fourth empty foil area are small, which can improve the energy density of the battery cell, and when the battery cell is subjected to external force, the electrode assembly is less likely to shake relative to the shell, so that the possibility of short circuit between the third empty foil area and the fourth pole piece, and between the fourth empty foil area and the third pole piece is small, thereby reducing the risk of thermal runaway of the battery cell; by making the first pole piece and the third pole piece have the same polarity, when observed along the first direction, at least part of the first empty foil area overlaps with the third empty foil area, and at least part of the second empty foil area overlaps with the fourth empty foil area, which can facilitate the first empty foil area to be connected to the third empty foil area and lead out of the shell, and facilitate the second empty foil area to be connected to the fourth empty foil area and lead out of the shell.

[0065] The battery cell provided in the embodiment of the present application can be a secondary battery or a primary battery, for example, a lithium ion battery, a sodium ion battery or a magnesium ion battery, etc., which is not limited in the embodiment of the present application. The electrochemical device can be cylindrical, flat, rectangular or other shapes, etc., which is not limited in the embodiment of the present application.

[0066] The embodiments of the present application provide an electrical device that uses a battery cell as a power source. The electrical device may be, but is not limited to, a mobile phone, a tablet, a laptop computer, an electric toy, an electric tool, an electric vehicle, an electric car, a ship, a spacecraft, and the like.

[0067] See also Figures 1 to 4 , Figure 1 A schematic diagram of a three-dimensional structure of a battery cell provided in some embodiments of the present application. Figure 2 A schematic diagram of the three-dimensional structure of an electrode assembly of a battery cell provided in some embodiments of the present application, Figure 3 A schematic structural diagram of a first pole piece and a second pole piece of a battery cell provided in some embodiments of the present application from one perspective; Figure 4 A schematic structural diagram of a third pole piece and a fourth pole piece of a battery cell provided in some embodiments of the present application from one perspective.

[0068] The embodiment of the present application provides a battery cell 10 , which includes a housing 100 and an electrode assembly 200 , wherein the electrode assembly 200 is accommodated in the housing 100 .

[0069] By accommodating the electrode assembly 200 in the housing 100 , the housing 100 can protect the electrode assembly 200 .

[0070] The battery cell 10 includes a housing 100, an electrode assembly 200 and an electrolyte, and the housing 100 is used to accommodate the electrode assembly 200 and the electrolyte. The electrode assembly 200 is composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell 10 mainly relies on the movement of metal ions between the positive electrode sheet and the negative electrode sheet to work. The positive electrode sheet includes a positive electrode collector and a positive electrode active material layer, and the positive electrode active material layer is coated on the surface of the positive electrode collector. The part of the positive electrode collector that is not coated with the positive electrode active material layer is used as a positive electrode ear to realize the input or output of electric energy of the positive electrode sheet through the positive electrode ear. The positive electrode ear and the positive electrode collector can also be set separately and then connected as one, for example, the positive electrode ear and the positive electrode collector are connected as one by welding connection, conductive glue connection, etc. Taking lithium-ion batteries as an example, the material of the positive electrode collector can be aluminum, and the positive electrode active material can be lithium cobalt oxide, lithium iron phosphate, ternary material or lithium manganese oxide. The negative electrode plate includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The portion of the negative electrode current collector that is not coated with the negative electrode active material layer serves as a negative electrode tab to realize the input or output of electrical energy of the negative electrode plate through the negative electrode tab. The negative electrode tab and the negative electrode current collector can also be separately arranged and then connected as one, for example, the negative electrode tab and the negative electrode current collector are connected as one by welding connection, conductive adhesive connection, etc. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon material or silicon material, etc. The material of the isolation membrane can be polypropylene (PP) or polyethylene (PE), etc. The electrolyte can include an organic solvent, an electrolyte lithium salt, etc.

[0071] In some embodiments, the electrode assembly can be a stacked electrode assembly, in which at least one positive electrode sheet, at least one negative electrode sheet and at least one isolation membrane are stacked in a certain order, and the isolation membrane is arranged between the positive electrode sheet and the negative electrode sheet to insulate and separate the positive electrode sheet and the negative electrode sheet, thereby reducing the risk of short circuit of the battery cell 10.

[0072] In some embodiments, the housing 100 may be made of materials such as aluminum-plastic film, steel-plastic film, etc.

[0073] In some embodiments, the electrode assembly 200 includes a first electrode plate group 210 and a second electrode plate group 220 stacked along a first direction X, the length of the first electrode plate group 210 along the second direction Y is less than the length of the second electrode plate group 220 along the second direction Y, and the first direction X is perpendicular to the second direction Y.

[0074] By making the electrode assembly 200 include a first electrode sheet group 210 and a second electrode sheet group 220 stacked along a first direction X, the length of the first electrode sheet group 210 along the second direction Y is less than the length of the second electrode sheet group 220 along the second direction Y, and the first direction X is perpendicular to the second direction Y, so that the electrode assembly 200 can form a step, so that the step can be used to place components, so that the battery cell can occupy other space in the battery compartment of the electrical device except the space where the components are located, thereby improving the space utilization of the battery compartment, and further improving the compactness of the internal structure of the electrical device. The electrode assembly forms a step, so that the electrode assembly can fully occupy the internal space of the shell, so that when the volume of the battery compartment is constant, the energy density of the battery cell is higher, which is conducive to improving the endurance of the electrical device.

[0075] In some embodiments, the first electrode set 210 includes a first electrode 211 and a second electrode 212 stacked along a first direction X and having opposite polarities, each first electrode 211 has a first notch 2111, each second electrode 212 has a second notch 2121, and when viewed along the first direction X, the first notch 2111 and the second notch 2121 do not overlap. Each first electrode 211 has a first empty foil area 2112 that at least partially overlaps with the second notch 2121, and each second electrode 212 has a second empty foil area 2122 that at least partially overlaps with the first notch 2111.

[0076] By making the first electrode plate group 210 include a first electrode plate 211 and a second electrode plate 212 which are stacked and arranged in a first direction X and have opposite polarities, each first electrode plate 211 has a first notch 2111, and each second electrode plate 212 has a second notch 2121, and when viewed along the first direction X, the first notch 2111 and the second notch 2121 do not overlap; each first electrode plate 211 has a first empty foil area 2112 which at least partially overlaps with the second notch 2121, and each second electrode plate 212 has a second empty foil area 2122 which at least partially overlaps with the first notch 2111, so that the first empty foil area 2112 and the second empty foil area 2122 are spaced apart on a vertical plane in the first direction X, the first empty foil area 2112 can be reduced. The possibility of short-circuiting due to contact with the second empty foil area 2122 can be reduced, and the volume of the first empty foil area 2112 protruding from the first electrode piece 211 can be reduced, and the volume of the second empty foil area 2122 protruding from the second electrode piece 212 can be reduced. The interval space reserved between the electrode assembly 200 and the outer shell 100 for accommodating the first empty foil area 2112 and the second empty foil area 2122 is small, which can improve the energy density of the battery cell 10, and when the battery cell 10 is subjected to external force, the possibility of the electrode assembly 200 shaking relative to the outer shell 100 is small, so that the possibility of short-circuiting due to contact between the first empty foil area 2112 and the second electrode piece 212, and the possibility of short-circuiting between the second empty foil area 2122 and the first electrode piece 211 is small, thereby reducing the risk of thermal runaway of the battery cell 10.

[0077] In some embodiments, the second pole piece group 220 includes a third pole piece 221 and a fourth pole piece 222 stacked along the first direction X and having opposite polarities, each third pole piece 221 has a third notch 2211, each fourth pole piece 222 has a fourth notch 2221, and when viewed along the first direction X, the third notch 2211 and the fourth notch 2221 do not overlap. Each third pole piece 221 has a third empty foil area 2212 that at least partially overlaps with the fourth notch 2221, and each fourth pole piece 222 has a fourth empty foil area 2222 that at least partially overlaps with the third notch 2211.

[0078] By making the second electrode sheet group 220 include a third electrode sheet 221 and a fourth electrode sheet 222 which are stacked and arranged along the first direction X and have opposite polarities, each third electrode sheet 221 has a third notch 2211, and each fourth electrode sheet 222 has a fourth notch 2221, and when observed along the first direction X, the third notch 2211 and the fourth notch 2221 do not overlap; each third electrode sheet 221 has a third empty foil area 2212 which at least partially overlaps with the fourth notch 2221, and each fourth electrode sheet 222 has a fourth empty foil area 2222 which at least partially overlaps with the third notch 2211, so that the third empty foil area 2212 and the fourth empty foil area 2222 are spaced apart on a vertical plane in the first direction X, the third empty foil area 2212 can be reduced. The possibility of short circuit caused by contact between the third empty foil area 2212 and the fourth empty foil area 2222 is reduced, and the volume of the third empty foil area 2212 protruding from the third pole piece 221 and the volume of the fourth empty foil area 2222 protruding from the fourth pole piece 222 can be reduced. The interval space reserved between the electrode assembly 200 and the shell 100 for accommodating the third empty foil area 2212 and the fourth empty foil area 2222 is small, which can improve the energy density of the battery cell 10. When the battery cell 10 is subjected to external force, the possibility of the electrode assembly 200 shaking relative to the shell 100 is small, so that the possibility of short circuit caused by contact between the third empty foil area 2212 and the fourth pole piece 222, and the fourth empty foil area 2222 and the third pole piece 221 is small, thereby reducing the risk of thermal runaway of the battery cell 10;

[0079] In some embodiments, the first electrode 211 and the third electrode 221 have the same polarity. When viewed along the first direction X, at least part of the first empty foil area 2112 overlaps with the third empty foil area 2212 , and at least part of the second empty foil area 2122 overlaps with the fourth empty foil area 2222 .

[0080] By making the first electrode 211 and the third electrode 221 have the same polarity, when observed along the first direction X, at least a portion of the first empty foil area 2112 overlaps with the third empty foil area 2212, and at least a portion of the second empty foil area 2122 overlaps with the fourth empty foil area 2222, so that the first empty foil area 2112 can be easily connected to the third empty foil area 2212 and led out of the shell 100, and the second empty foil area 2122 can be easily connected to the fourth empty foil area 2222 and led out of the shell 100.

[0081] In some embodiments, the first empty foil area 2112 and the second empty foil area 2122 are located at one end of the first electrode assembly 210 along the third direction Z. The third empty foil area 2212 and the fourth empty foil area 2222 are located at one end of the second electrode assembly 220 along the third direction Z.

[0082] The first direction X, the second direction Y, and the third direction Z are perpendicular to each other.

[0083] By locating the first empty foil area 2112 and the second empty foil area 2122 at one end of the first electrode plate group 210 along the third direction Z; and locating the third empty foil area 2212 and the fourth empty foil area 2222 at one end of the second electrode plate group 220 along the third direction Z, only one side of the spacing space needs to be reserved between the housing 100 and the electrode assembly 200 to accommodate the first empty foil area 2112, the second empty foil area 2122, the third empty foil area 2212 and the fourth empty foil area 2222, thereby further improving the energy density of the battery cell 10.

[0084] In some embodiments, the first pole piece 211 has a first coating area 2113 , and along the second direction Y, a portion of the first coating area 2113 is located between the first notch 2111 and the first empty foil area 2112 .

[0085] The first pole piece 211 has a second coating area 2123 . Along the second direction Y, a portion of the second coating area 2123 is located between the second notch 2121 and the second empty foil area 2122 .

[0086] Due to the steps of the battery cell 10, the sizes of the first electrode group 210 and the second electrode group 220 are different, and the first empty foil area 2112 and the second empty foil area 2122 are located on the overlapping side of the first electrode group 210 and the second electrode group 220, which will cause uneven distribution of internal force when the battery cell 10 is subjected to force, and there is a risk of damage or even breakage of the first empty foil area 2112 and the second empty foil area 2122. By making a part of the first coating area 2113 located between the first notch 2111 and the first empty foil area 2112 along the second direction Y, and a part of the second coating area 2123 located between the second notch 2121 and the second empty foil area 2122, the internal force distribution of the battery cell 10 when subjected to force can be made more uniform, and the risk of damage or even breakage of the first empty foil area 2112 and the second empty foil area 2122 is reduced, thereby playing a protective role for the first empty foil area 2112 and the second empty foil area 2122.

[0087] In some embodiments, the first notch 2111 and the first empty foil area 2112 are respectively located at two corners of the first pole piece 211 .

[0088] The second notch 2121 and the second empty foil area 2122 are respectively located at two corners of the second pole piece 212 .

[0089] By locating the first notch 2111 and the first empty foil area 2112 at two corners of the first electrode 211, and the second notch 2121 and the second empty foil area 2122 at two corners of the second electrode 212, respectively, it is possible to facilitate the preparation of the first notch 2111, the first empty foil area 2112, the second notch 2121 and the second empty foil area 2122, and to facilitate the lead-out of the first empty foil area 2112 and the second empty foil area 2122, thereby further reducing the possibility of short circuit between the first empty foil area 2112 and the second electrode 212, and between the second empty foil area 2122 and the first electrode 211.

[0090] The angular position in the present application refers to the position at the top corner of the pole piece. For example, the first empty foil area 2112 is located at the angular position of the first pole piece 211, that is, at least one edge of the first empty foil area 2112 coincides with the edge of the first pole piece 211; for example, the second empty foil area 2122 is located at the angular position of the second pole piece 212, that is, the second empty foil area 2122 extends out from one end of the second pole piece 212 along the third direction Z, and along the second direction, one side of the second empty foil area 2122 at least partially overlaps with the projection of the second pole piece 212, and the other side of the second empty foil area 2122 is close to the edge of the second pole piece 212.

[0091] In some embodiments, the third pole piece 221 has a third coating area 2213 , and along the second direction Y, a portion of the third coating area 2213 is located between the third notch 2211 and the third empty foil area 2212 .

[0092] The fourth pole piece 222 has a fourth coating area 2223 . Along the second direction Y, a portion of the fourth coating area 2223 is located between the fourth notch 2221 and the fourth empty foil area 2222 .

[0093] Due to the steps of the battery cell 10, the sizes of the first electrode group 210 and the second electrode group 220 are different, and the third empty foil area 2212 and the fourth empty foil area 2222 are located on the overlapping side of the first electrode group 210 and the second electrode group 220, which will cause the internal force distribution of the battery cell 10 to be uneven when the force is applied, and the third empty foil area 2212 and the fourth empty foil area 2222 are at risk of being damaged or even broken. By making a part of the third coating area 2213 located between the third notch 2211 and the third empty foil area 2212, and a part of the fourth coating area 2223 located between the fourth notch 2221 and the fourth empty foil area 2222 along the second direction Y, the internal force distribution of the battery cell 10 can be made more uniform when the force is applied, and the risk of damage or even breakage of the third empty foil area 2212 and the fourth empty foil area 2222 is reduced, thereby protecting the third empty foil area 2212 and the fourth empty foil area 2222.

[0094] In some embodiments, the third notch 2211 and the third empty foil area 2212 are respectively located at two corners of the third pole piece 221 .

[0095] The fourth notch 2221 is located at a corner of the fourth pole piece 222. The fourth pole piece 222 has a first edge 222a and a second edge 222b that are opposite to each other along the second direction Y. The first edge 222a and the fourth notch 2221 are located on the same side of the fourth pole piece 222. Along the second direction Y, the distance between the fourth empty foil area 2222 and the second edge 222b is D1, the width of the second pole piece 212 is W1, and the width of the fourth pole piece 222 is W2, satisfying 0≤D1-(W2-W1)≤6mm. For example, D1-(W2-W1) can be 0, 3mm, or 6mm, etc.

[0096] By locating the third notch 2211 and the third empty foil area 2212 at two corners of the third pole piece 221 respectively and the fourth notch 2221 at one corner of the fourth pole piece 222, it is easy to prepare the third notch 2211, the third empty foil area 2212 and the fourth notch 2221 and to lead out the third empty foil area 2212. When D1-(W2-W1) is greater than or equal to 0, the second empty foil area 2122 can overlap with the fourth empty foil area 2222 in the first direction X, thereby facilitating the connection and lead-out of the second empty foil area 2122 and the fourth empty foil area 2222; when D1-(W2-W1) is greater than 6 mm, the distance between the third empty foil area 2212 and the fourth empty foil area 2222 is small, which may cause the risk of contact between the third empty foil area 2212 and the fourth empty foil area 2222 during use; therefore, when 0≤D1-(W2-W1)≤6 mm, it can not only facilitate the connection and lead-out of the second empty foil area 2122 and the fourth empty foil area 2222, but also help to improve the safety performance of the battery cell 10.

[0097] In some embodiments, 0≤D1-(W2-W1)≤2 mm. For example, D1-(W2-W1) may be 0, 1 mm, or 2 mm.

[0098] When D1-(W2-W1) is greater than or equal to 0, the second empty foil area 2122 can overlap with the fourth empty foil area 2222 in the first direction X, thereby facilitating the connection and lead-out of the second empty foil area 2122 and the fourth empty foil area 2222; when D1-(W2-W1) is less than or equal to 2 mm, the distance between the third empty foil area 2122 and the fourth empty foil area 2222 is further increased, reducing the possibility of interference contact between the two, which is beneficial to further improve the safety performance of the battery cell 10; therefore, when 0≤D1-(W2-W1)≤2 mm, it can not only facilitate the connection and lead-out of the second empty foil area 2122 and the fourth empty foil area 2222, but also be beneficial to further improve the safety performance of the battery cell 10.

[0099] In some embodiments, along the second direction Y, the width of the second pole piece 212 is W1, and the width of the fourth pole piece 222 is W2, satisfying 1mm≤W2-W1≤3 / 4*W2. For example, W2-W1 can be 1mm, 1 / 4*W2, or 3 / 4*W2.

[0100] When W2-W1 is greater than or equal to 1mm, the step formed by the battery cell 10 can be used to accommodate other components; when W2-W1 is less than or equal to 3 / 4*W2, the width of the coated area of ​​each electrode between the notch and the empty foil area is larger, which is beneficial to improving the energy density of the battery cell 10 and can reduce the risk of pressing the battery cell 10 during the formation process; therefore, when 1mm≤W2-W1≤3 / 4*W2, it can facilitate the step formed by the battery cell 10 to accommodate other components, and can also help improve the energy density of the battery cell 10 and reduce the risk of pressing the battery cell 10 during the formation process.

[0101] In some embodiments, 1 mm ≤ W2 - W1 ≤ 1 / 2*W2. For example, W2 - W1 may be 1 mm, 1 / 3*W2, or 1 / 2*W2.

[0102] When W2-W1 is greater than or equal to 1mm, the step formed by the battery cell 10 can be used to accommodate other components; when W2-W1 is less than or equal to 1 / 2*W2, the width of the coated area of ​​each electrode between the notch and the empty foil area is further increased, which is beneficial to further improve the energy density of the battery cell 10 and can further reduce the risk of pressing the battery cell 10 during the formation process; therefore, when 1mm≤W2-W1≤3 / 4*W2, it can facilitate the step formed by the battery cell 10 to accommodate other components, and can also help further improve the energy density of the battery cell 10 and can further reduce the risk of pressing the battery cell 10 during the formation process.

[0103] See also Figure 3 , Figures 5 to 7 , Figure 5 Schematic diagram of the three-dimensional structure of the battery cell provided in some other embodiments of the present application, Figure 6 Schematic diagram of the three-dimensional structure of the electrode assembly of the battery cell provided in some other embodiments of the present application, Figure 7 A schematic structural diagram of a third pole piece and a fourth pole piece of a battery cell from one perspective provided in some other embodiments of the present application.

[0104] Some embodiments of the present application provide another battery cell 10, the battery cell 10 includes a housing 100 and an electrode assembly 200, and the electrode assembly 200 is accommodated in the housing 100. The electrode assembly 200 includes a first electrode sheet group 210 and a second electrode sheet group 220 stacked along a first direction X, wherein Figure 3 The structure of the first pole piece group 210 is similar to the structure of the first pole piece group 210 in the above-mentioned embodiment of the battery cell 10. The difference between the embodiment of the present application and the above-mentioned embodiment of the battery cell 10 lies in the structure of the second pole piece group 220.

[0105] In some embodiments, the third empty foil area 2212 is located at a corner of the third pole piece 221, the third pole piece 221 includes a third coating area 2213, and along the second direction Y, the third notch 2211 is provided with a third coating area 2213 on both sides. The fourth notch 2221 is located at a corner of the fourth pole piece 222, the fourth pole piece 222 includes a fourth coating area 2223, and along the second direction Y, the third notch 2211 is provided with a fourth coating area 2223 on both sides.

[0106] By locating the third empty foil area 2212 at a corner of the third pole piece 221 and the fourth notch 2221 at a corner of the fourth pole piece 222 , the preparation of the third empty foil area 2212 and the fourth notch 2221 can be facilitated. Due to the steps of the battery cell 10, the sizes of the first electrode group 210 and the second electrode group 220 are different, and the third empty foil area 2212 and the fourth empty foil area 2222 are located on the overlapping side of the first electrode group 210 and the second electrode group 220, which will cause uneven distribution of internal force when the battery cell 10 is subjected to force, and there is a risk of damage or even breakage of the third empty foil area 2212 and the fourth empty foil area 2222. By providing the third coating area 2213 on both sides of the third notch 2211 along the second direction Y, and providing the fourth coating area 2223 on both sides of the third notch 2211, the internal force distribution of the battery cell 10 when subjected to force can be made more uniform, and the risk of damage or even breakage of the third empty foil area 2212 and the fourth empty foil area 2222 is reduced, thereby protecting the third empty foil area 2212 and the fourth empty foil area 2222.

[0107] See also Figure 2 and Figure 6 In some embodiments, the first pole piece group 210 has a first end and a second end opposite to each other along the second direction Y, and the second pole piece group 220 has a third end and a fourth end opposite to each other along the second direction Y, the first end is flush with the third end, and the fourth end exceeds the second end.

[0108] By making the first electrode plate group 210 have a first end and a second end opposite to each other along the second direction Y, and the second electrode plate group 220 have a third end and a fourth end opposite to each other along the second direction Y, the first end is flush with the third end, and the fourth end exceeds the second end, the assembly of the first electrode plate group 210 and the second electrode plate group 220 can be facilitated, and a step is formed on one side of the battery cell 10 along the second direction Y, so as to facilitate the accommodation of components of the electrical equipment.

[0109] See also Figures 8 to 11 , Figure 8 A schematic diagram of a three-dimensional structure of a battery cell provided in some other embodiments of the present application; Fig. 9 A schematic diagram of the three-dimensional structure of an electrode assembly of a battery cell provided in some other embodiments of the present application; Fig.10A schematic structural diagram of a first pole piece and a second pole piece of a battery cell provided in some other embodiments of the present application from one perspective; Fig.11 A schematic structural diagram of a third pole piece and a fourth pole piece of a battery cell from one perspective provided in some other embodiments of the present application.

[0110] Some embodiments of the present application provide another battery cell 10, which includes a housing 100 and an electrode assembly 200, wherein the electrode assembly 200 is accommodated in the housing 100. The electrode assembly 200 includes a first electrode sheet group 210 and a second electrode sheet group 220 stacked along a first direction X.

[0111] In some embodiments, the first pole piece group 210 includes a first pole piece 211 and a second pole piece 212 stacked along a first direction X and having opposite polarities, the first pole piece 211 having a first empty foil area 2112, and the second pole piece 212 having a second empty foil area 2122. The second pole piece group 220 includes a third pole piece 221 and a fourth pole piece 222 stacked along the first direction X and having opposite polarities, the third pole piece 221 having a third empty foil area 2212, and the fourth pole piece 222 having a fourth empty foil area 2222.

[0112] In some embodiments, the first empty foil area 2112 and the second empty foil area 2122 are located at one end of the first electrode group 210 along the second direction Y, and the second electrode group 220 exceeds the other end of the first electrode group 210 along the second direction Y. The third empty foil area 2212 and the fourth empty foil area 2222 are located at one end of the second electrode group 220 along the second direction Y.

[0113] By locating the first empty foil area 2112 and the second empty foil area 2122 at one end of the first electrode plate group 210 along the second direction Y, and locating the third empty foil area 2212 and the fourth empty foil area 2222 at one end of the second electrode plate group 220 along the second direction Y, the first empty foil area 2112 and the third empty foil area 2212 can be connected and led out at one end of the electrode assembly 200 along the second direction Y, and the second empty foil area 2122 and the fourth empty foil area 2222 can be connected and led out at one end of the electrode assembly 200 along the second direction Y; by making the second electrode plate group 220 extend beyond the other end of the first electrode plate group 210 along the second direction Y, a step can be formed at the other end of the battery cell 10 along the second direction Y, so as to facilitate the accommodation of components of electrical equipment.

[0114] In some embodiments, the third notch 2211 and the third empty foil area 2212 are respectively located at two corners of the third pole piece 221, and the third pole piece 221 has a third coating area 2213. Along the third direction Z, a portion of the third coating area 2213 is located between the third notch 2211 and the third empty foil area 2212. The fourth notch 2221 and the fourth empty foil area 2222 are respectively located at two corners of the fourth pole piece 222, and the fourth pole piece 222 has a fourth coating area 2223. Along the third direction Z, a portion of the fourth coating area 2223 is located between the fourth notch 2221 and the fourth empty foil area 2222. The first direction X, the second direction Y, and the third direction Z are perpendicular to each other.

[0115] By making the third notch 2211 and the third empty foil area 2212 respectively located at two corners of the third pole piece 221, and the fourth notch 2221 and the fourth empty foil area 2222 respectively located at two corners of the fourth pole piece 222, it is possible to facilitate the preparation of the third empty foil area 2212, the third notch 2211, the fourth empty foil area 2222 and the fourth notch 2221, and the first pole piece group 210, the second pole piece group 220, the first empty foil area 2112 and the second empty foil area 2122, the third empty foil area 2212 and the fourth empty foil area 2222 are symmetrically arranged relative to the central axis of the battery cell 10 along the second direction Y, so that when the battery cell 10 is subjected to force, the internal force distribution can be more uniform, and the possibility of internal damage to the battery cell 10 is lower. Due to the steps of the battery cell 10, the sizes of the first electrode group 210 and the second electrode group 220 are different, and the third empty foil area 2212 and the fourth empty foil area 2222 are located on the overlapping side of the first electrode group 210 and the second electrode group 220, which will cause the internal force distribution of the battery cell 10 to be still uneven when subjected to force, and there is a risk of damage or even breakage of the third empty foil area 2212 and the fourth empty foil area 2222. By making a part of the third coating area 2213 located between the third notch 2211 and the third empty foil area 2212, and a part of the fourth coating area 2223 located between the fourth notch 2221 and the fourth empty foil area 2222 along the third direction Z, the internal force distribution of the battery cell 10 can be made more uniform when subjected to force, and the risk of damage or even breakage of the third empty foil area 2212 and the fourth empty foil area 2222 is reduced, thereby protecting the third empty foil area 2212 and the fourth empty foil area 2222.

[0116] See also Fig.12 and Fig.13 , Fig.12 A schematic structural diagram of a battery cell from one perspective provided in some embodiments of the present application; Fig.13 for Fig.12 A schematic diagram of the partially enlarged structure of the cross-sectional view of the battery cell along the AA direction.

[0117] In some embodiments, the first electrode 211 is a positive electrode, and the second electrode 212 is a negative electrode; the distance between the end of the second electrode 212 provided with the second empty foil area 2122 and the housing 100 is D2, which satisfies 0.4 mm ≤ D2 ≤ 0.5 mm. For example, D2 can be 0.4 mm, 0.45 mm or 0.5 mm.

[0118] Since the size of the negative electrode sheet is generally larger than that of the positive electrode sheet, the spacing distance between the negative electrode sheet and the housing 100 is the spacing distance between the electrode assembly 200 and the housing 100. By making the spacing distance D2 between the end of the second electrode sheet 212 provided with the second empty foil area 2122 and the housing 100 satisfy 0.4mm≤D2≤0.5mm, it is possible to further facilitate the assembly of the electrode assembly 200 and the housing 100, and to accommodate the electrolyte, and it is also possible to further make the energy density of the battery cell 10 higher. And if a notch is not provided in the battery cell 10 to accommodate the empty foil area, the empty foil area protrudes, which will occupy the space between the housing 100 and the electrode assembly 200, affecting the energy density of the battery cell 10. In this solution, a notch is provided in the electrode sheet to accommodate the empty foil area, so that the distance between the end of the second electrode sheet 212 provided with the second empty foil area 2122 and the inner wall of the housing 100 can be limited to within the above range.

[0119] See also Figure 1 , Fig.12 and Fig.13 In some embodiments, the battery cell 10 includes a first electrical connector 310 and a second electrical connector 320, the first electrical connector 310 and the second electrical connector 320 are located on the same side of the electrode assembly 200, the first electrical connector 310 is connected to the first empty foil area 2112 and the third empty foil area 2212, and the second electrical connector 320 is connected to the second empty foil area 2122 and the fourth empty foil area 2222. The housing 100 includes a main body 110 and a sealing part 120, the sealing part 120 includes a top sealing part 121 and a side sealing part 122, the top sealing part 121 is located between the first electrical connector 310 and the second electrical connector 320, and the top sealing part 121 is bent toward the main body 110.

[0120] By making the battery cell 10 include the first electrical connector 310 and the second electrical connector 320, the first electrical connector 310 and the second electrical connector 320 are located on the same side of the electrode assembly 200, the first electrical connector 310 is connected to the first empty foil area 2112 and the third empty foil area 2212, and the second electrical connector 320 is connected to the second empty foil area 2122 and the fourth empty foil area 2222, so that the load can be electrically connected to the battery cell 10 through the first electrical connector 310 and the second electrical connector 320; if the battery cell 10 is not provided with a notch to accommodate the empty foil area, the empty foil area protrudes, and the first electrical connector 310 and the second electrical connector 320 connected to the empty foil area are connected to the first electrical connector 310 and the third empty foil area 2212. The second electrical connector 320 extends from the top sealing portion of the outer shell 100, and the top sealing portion extends in a straight line and cannot be bent, resulting in a larger size of the battery cell 10 along the direction in which the first electrical connector 310 extends out of the sealing portion, affecting the energy density of the battery cell 10. Therefore, by making the empty foil area of ​​the battery cell 10 located in the notch, the top sealing portion 121 located between the first electrical connector 310 and the second electrical connector 320 protrudes from other parts of the sealing portion 120, and the top sealing portion 121 is bent toward the main body 110. This can make the size of the battery cell 10 along the direction in which the first electrical connector 310 extends out of the sealing portion 120 smaller, which is beneficial to improving the energy density of the battery cell 10.

[0121] In some embodiments, the first electrical connector 210 and the positive electrical connector may be connected by welding, and the second electrical connector 220 and the negative electrical connector may be connected by welding.

[0122] In other embodiments, the first electrical connector 210 and the positive electrical connector may be integrally formed, and the second electrical connector 220 and the negative electrical connector may be integrally formed.

[0123] In some embodiments, the first electrical connector 210 and the second electrical connector 220 may be made of a material with good electrical conductivity, such as a metal material such as lead or copper.

[0124] In some embodiments, along the direction in which the first electrical connector extends out of the housing ( Figure 1 The third direction shown or Figure 8 The distance between the surface of the first sealing portion 121 facing away from the main body 110 and the surface of the main body 110 facing the first sealing portion 121 is S, and 0.2 mm ≤ S ≤ 0.5 mm is satisfied. For example, S can be 0.2 mm, 0.3 mm, or 0.5 mm.

[0125] When S is greater than or equal to 0.2 mm, the thickness of the first sealing portion 121 is relatively large, so that the sealing effect of the first sealing portion 121 is better, the battery cell 10 is not prone to damage, leakage, etc., and the battery cell 10 is safer; when S is less than or equal to 0.5 mm, the size of the first sealing portion 121 in the direction in which the first electrical connector 310 extends out of the top sealing portion 120 is smaller, so that the size of the battery cell 10 along the direction in which the first electrical connector 310 extends out of the sealing portion 120 is smaller, which is beneficial to improving the energy density of the battery cell 10; therefore, when 0.2 mm ≤ S ≤ 0.5 mm, it can not only make the sealing effect of the first sealing portion 121 better, the battery cell 10 is not prone to damage, leakage, etc., the battery cell 10 is safer, but also can be beneficial to improving the energy density of the battery cell 10.

[0126] See also Fig.14 , Fig.14 A schematic structural diagram of an electrode assembly of a battery cell from one perspective provided in some other embodiments of the present application.

[0127] In other embodiments, the first pole piece group 210 has a first end and a second end opposite to each other along the second direction Y, and the second pole piece group 220 has a third end and a fourth end opposite to each other along the second direction Y, the third end exceeds the first end, and the fourth end exceeds the second end.

[0128] By making the first electrode plate group 210 have a first end and a second end opposite to each other along the second direction Y, and the second electrode plate group 220 have a third end and a fourth end opposite to each other along the second direction Y, with the third end extending beyond the first end and the fourth end extending beyond the second end, the assembly of the first electrode plate group 210 and the second electrode plate group 220 can be facilitated, and steps are formed on both sides of the battery cell 10 along the second direction Y, so as to facilitate the accommodation of components of electrical equipment.

[0129] See also Fig.15 , Fig.15 A schematic structural diagram of an electrode assembly of a battery cell from one perspective provided in some other embodiments of the present application.

[0130] In some embodiments, the electrode assembly 200 includes a third electrode sheet group 230, and the third electrode sheet group 230 includes a fifth electrode sheet and a sixth electrode sheet (not shown in the figure) stacked along the first direction X and having opposite polarities, each fifth electrode sheet has a fifth notch, each sixth electrode sheet has a sixth notch, and the fifth notch and the sixth notch do not overlap when viewed along the first direction X. Each fifth electrode sheet has a fifth empty foil area that at least partially overlaps with the sixth notch, and each sixth electrode sheet has a sixth empty foil area that at least partially overlaps with the fifth notch. The fifth empty foil area and the sixth empty foil area are spaced apart on a plane vertical to the first direction X, which can reduce the possibility of short circuit between the fifth empty foil area and the sixth empty foil area, and can reduce the volume of the fifth empty foil area protruding from the fifth pole piece, and reduce the volume of the sixth empty foil area protruding from the sixth pole piece. The spacing space reserved between the electrode assembly 200 and the shell 100 for accommodating the fifth empty foil area and the sixth empty foil area is small, which can improve the energy density of the battery cell 10, and when the battery cell 10 is subjected to external force, the electrode assembly 200 is less likely to shake relative to the shell 100, so that the possibility of short circuit between the fifth empty foil area and the sixth pole piece, and between the sixth empty foil area and the fifth pole piece is less, thereby reducing the risk of thermal runaway of the battery cell 10.

[0131] In some embodiments, the fifth pole piece has the same polarity as the third pole piece 221, and when viewed along the first direction X, at least a portion of the fifth empty foil area overlaps with the third empty foil area 2212, and at least a portion of the sixth empty foil area overlaps with the fourth empty foil area 2222. This facilitates the fifth empty foil area to be connected to the third empty foil area 2212 and lead out of the housing 100, and facilitates the sixth empty foil area to be connected to the fourth empty foil area 2222 and lead out of the housing 100.

[0132] In some embodiments, the first pole piece group 210 has a first end and a second end opposite to each other along the second direction Y, the second pole piece group 220 has a third end and a fourth end opposite to each other along the second direction Y, the third pole piece group 230 has a fifth end and a sixth end opposite to each other along the second direction Y, the first end, the third end, and the fifth end are flush, the fourth end exceeds the second end, and the fourth end exceeds the sixth end. It is convenient to assemble the first pole piece group 210, the second pole piece group 220, and the third pole piece group 230, and steps are formed on both sides of the battery cell 10 along the first direction, so as to facilitate the accommodation of components of the electrical equipment.

[0133] See also Fig.16 , Fig.16 A schematic structural diagram of an electrode assembly of a battery cell from one perspective provided in some other embodiments of the present application.

[0134] In some embodiments, the first pole piece group 210 has a first end and a second end opposite to each other along the second direction Y, the second pole piece group 220 has a third end and a fourth end opposite to each other along the second direction Y, the third pole piece group 230 has a fifth end and a sixth end opposite to each other along the second direction Y, the first end is flush with the third end, the fourth end is beyond the second end; the fourth end is flush with the sixth end, and the third end is beyond the fifth end. It is convenient to assemble the first pole piece group 210, the second pole piece group 220, and the third pole piece group 230, and steps are formed on both sides of the battery cell 10 along the first direction, so as to facilitate the accommodation of components of the electrical equipment.

[0135] See also Fig.17 , Fig.17 A schematic structural diagram of an electrode assembly of a battery cell from one perspective provided in some other embodiments of the present application.

[0136] In some embodiments, the first pole piece group 210 has a first end and a second end opposite to each other along the second direction Y, the second pole piece group 220 has a third end and a fourth end opposite to each other along the second direction Y, the third pole piece group 230 has a fifth end and a sixth end opposite to each other along the second direction Y, the first end, the third end, and the fifth end are flush, the fourth end exceeds the second end, and the sixth end exceeds the fourth end. It is convenient to assemble the first pole piece group 210, the second pole piece group 220, and the third pole piece group 230, and two steps are formed on the battery cell 10, so as to facilitate the placement of components of the electrical equipment.

[0137] An embodiment of the present application provides an electrical device, comprising a battery cell 10 according to any of the above solutions, and the battery cell 10 is used to provide electrical energy to the electrical device.

[0138] In some embodiments, the electrical device has a battery compartment, the battery cell 10 is accommodated in the battery compartment, and the step formed by the battery cell 10 is used to avoid components arranged in the battery compartment.

[0139] The electrical device may be any of the aforementioned devices or systems using the battery cell 10 .

[0140] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0141] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A battery cell, characterized in that: It comprises a housing and an electrode assembly, wherein the electrode assembly is accommodated in the housing; The electrode assembly comprises a first electrode group and a second electrode group stacked along a first direction, the length of the first electrode group along the second direction is less than the length of the second electrode group along the second direction, and the first direction is perpendicular to the second direction; The first pole piece group comprises a first pole piece and a second pole piece which are stacked along the first direction and have opposite polarities, each of the first pole pieces has a first notch, each of the second pole pieces has a second notch, and when viewed along the first direction, the first notch and the second notch do not overlap; each of the first pole pieces has a first empty foil area which at least partially overlaps with the second notch, and each of the second pole pieces has a second empty foil area which at least partially overlaps with the first notch; The second electrode sheet group comprises a third electrode sheet and a fourth electrode sheet which are stacked along the first direction and have opposite polarities, each of the third electrode sheets has a third notch, each of the fourth electrode sheets has a fourth notch, and when viewed along the first direction, the third notch and the fourth notch do not overlap; each of the third electrode sheets has a third empty foil area which at least partially overlaps with the fourth notch, and each of the fourth electrode sheets has a fourth empty foil area which at least partially overlaps with the third notch; The first pole piece and the third pole piece have the same polarity. When viewed along the first direction, at least a portion of the first empty foil area overlaps with the third empty foil area, and at least a portion of the second empty foil area overlaps with the fourth empty foil area.

2. The battery cell according to claim 1, characterized in that: The first empty foil area and the second empty foil area are located at one end of the first electrode assembly along the third direction; The third empty foil area and the fourth empty foil area are located at one end of the second pole piece group along the third direction; The first direction, the second direction, and the third direction are perpendicular to each other.

3. The battery cell according to claim 2, characterized in that: The first pole piece has a first coating area, and along the second direction, a portion of the first coating area is located between the first notch and the first empty foil area; The second pole piece has a second coating area, and along the second direction, a portion of the second coating area is located between the second notch and the second empty foil area.

4. The battery cell according to claim 3, characterized in that: The first notch and the first empty foil area are respectively located at two corners of the first pole piece; The second notch and the second empty foil area are respectively located at two corners of the second pole piece.

5. The battery cell according to claim 3, characterized in that: The third pole piece has a third coating area, and along the second direction, a portion of the third coating area is located between the third notch and the third empty foil area; The fourth pole piece has a fourth coating area, and along the second direction, a portion of the fourth coating area is located between the fourth notch and the fourth empty foil area.

6. The battery cell according to claim 5, characterized in that: The third notch and the third empty foil area are respectively located at two corners of the third pole piece; The fourth notch is located at a corner of the fourth pole piece, and the fourth pole piece has a first edge and a second edge opposite to each other along the second direction, and the first edge and the fourth notch are located on the same side of the fourth pole piece; along the second direction, the distance between the fourth empty foil area and the second edge is D1, the width of the second pole piece is W1, and the width of the fourth pole piece is W2, satisfying 0≤D1-(W2-W1)≤6mm.

7. The battery cell according to claim 6, characterized in that: 0≤D1-(W2-W1)≤2mm.

8. The battery cell according to claim 5, characterized in that: Along the second direction, the width of the second pole piece is W1, and the width of the fourth pole piece is W2, satisfying 1mm≤W2-W1≤3 / 4*W2.

9. The battery cell according to claim 8, characterized in that: 1mm≤W2-W1≤1 / 2*W2.

10. The battery cell according to claim 3, characterized in that: The third empty foil area is located at a corner of the third pole piece, and the third pole piece includes a third coating area. The third coating area is provided on both sides of the third notch along the second direction; The fourth notch is located at a corner of the fourth pole piece. The fourth pole piece includes a fourth coating area. The fourth coating area is disposed on both sides of the third notch along the second direction.

11. The battery cell according to claim 2, characterized in that: The first pole piece group has a first end and a second end opposite to each other along the second direction, the second pole piece group has a third end and a fourth end opposite to each other along the second direction, the first end is flush with the third end, and the fourth end exceeds the second end.

12. The battery cell according to claim 1, characterized in that: The first empty foil area and the second empty foil area are located at one end of the first pole piece group along the second direction, and the second pole piece group exceeds the other end of the first pole piece group along the second direction; The third empty foil area and the fourth empty foil area are located at one end of the second pole piece group along the second direction.

13. The battery cell according to claim 12, characterized in that: The third notch and the third empty foil area are respectively located at two corners of the third pole piece, the third pole piece has a third coating area, and along the third direction, a part of the third coating area is located between the third notch and the third empty foil area; The fourth notch and the fourth empty foil area are respectively located at two corners of the fourth pole piece, the fourth pole piece has a fourth coating area, and along the third direction, a portion of the fourth coating area is located between the fourth notch and the fourth empty foil area; The first direction, the second direction and the third direction are perpendicular to each other.

14. The battery cell according to any one of claims 1 to 13, characterized in that: The first pole piece is a positive pole piece, and the second pole piece is a negative pole piece; The spacing distance between the end of the second pole piece provided with the second empty foil area and the housing is D2, satisfying 0.4mm≤D2≤0.5mm.

15. The battery cell according to any one of claims 1 to 13, characterized in that: The battery core comprises a first electrical connector and a second electrical connector, wherein the first electrical connector and the second electrical connector are located on the same side of the electrode assembly, the first electrical connector is connected to the first empty foil area and the third empty foil area, and the second electrical connector is connected to the second empty foil area and the fourth empty foil area; The housing includes a main body and a sealing portion, the sealing portion includes a top sealing portion and a side sealing portion, the top sealing portion is located between the first electrical connector and the second electrical connector, and the top sealing portion is bent toward the main body.

16. The battery cell according to claim 15, characterized in that: Along the direction in which the first electrical connector extends out of the housing, a distance S between a surface of the first sealing portion facing away from the main body and a surface of the main body facing the first sealing portion satisfies 0.2 mm ≤ S ≤ 0.5 mm.

17. An electrical equipment, characterized in that: The battery cell comprises a battery cell as claimed in any one of claims 1 to 16, wherein the battery cell is used to provide electrical energy.

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