Battery cell, battery device and electric device

Abstract

The utility model discloses a battery monomer, a battery device and a power utilization device. The battery cell includes a housing and an electrode assembly. The shell is provided with a first wall and a second wall opposite to each other in the first direction, the first wall is provided with a liquid injection hole, and the liquid injection hole is used for injecting electrolyte into the shell. The electrode assembly is disposed inside the housing. Wherein a weak part and a pressure relief area are formed on the second wall, the second wall is configured to be capable of cracking along the weak part so as to open the pressure relief area, and the projection of the liquid injection hole and the projection of the weak part are not overlapped on the same projection plane perpendicular to the first direction. According to the technical scheme provided by the invention, the manufacturing efficiency of the battery device can be improved.

Description

Technical Field

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

[0002] Energy conservation and emission reduction are key to the sustainable development of the automotive industry. Electric vehicles, due to their energy-saving and environmentally friendly advantages, have become an important component of the sustainable development of the automotive industry. For electric vehicles, battery technology is a key factor in their development.

[0003] In the development of battery technology, how to improve the manufacturing efficiency of battery devices is a technical problem that needs to be solved urgently. Utility Model Content

[0004] The present application provides a battery cell, a battery device, and an electrical device. The technical solution provided in the present application can improve the manufacturing efficiency of the battery device.

[0005] In a first aspect, some embodiments of the present application provide a battery cell, comprising a housing and an electrode assembly. The housing has a first wall and a second wall opposite to each other along a first direction, the first wall having an injection hole for injecting electrolyte into the interior of the housing. The electrode assembly is disposed within the housing. The second wall is formed with a weak portion and a pressure relief zone, the second wall being configured to be able to rupture along the weak portion to open the pressure relief zone, and the projection of the injection hole and the projection of the weak portion do not overlap on the same projection plane perpendicular to the first direction.

[0006] In the above scheme, on the one hand, the injection hole and the weak part are respectively provided on the first wall and the second wall opposite to each other of the shell. Compared with the scheme in which the injection hole and the weak part are provided on the same wall, the interference of the weak part or the injection hole on other structural parts can be reduced, so as to improve the space utilization rate of other structural parts at the battery device level, for example, the interference of the weak part or the injection hole on the external convergence component is reduced, thereby facilitating the improvement of the volume energy density of the battery device; on the other hand, by arranging the projections of the injection hole and the weak part on the same projection plane perpendicular to the first direction to not overlap with each other, the pressure generated when the electrolyte is injected into the shell by the injection hole can be effectively reduced to impact the weak part, causing the weak part to be damaged and ruptured, resulting in the risk of the battery cell being scrapped, so that the battery cell has a higher yield rate during the manufacturing process, thereby facilitating the improvement of the battery cell manufacturing efficiency, and further facilitating the improvement of the battery device manufacturing efficiency.

[0007] According to some embodiments of the present application, on the same projection plane perpendicular to the first direction, the minimum distance between the projection of the liquid injection hole and the projection of the weak portion is greater than or equal to 5 mm and less than or equal to 50 mm.

[0008] In the above scheme, by setting the minimum distance between the projections of the injection hole and the weak part on the same projection plane perpendicular to the first direction to be greater than or equal to 5mm, the influence of the pressure generated during electrolyte injection on the weak part can be effectively reduced, and the risk of the battery cell being scrapped due to rupture of the weak part can be reduced. By setting the minimum distance between the projections of the injection hole and the weak part on the same projection plane perpendicular to the first direction to be less than or equal to 50mm, the interference of the injection hole or the weak part on other structural parts can be reduced, so that at the battery device level, the battery device structure is compact, which is conducive to the improvement of the volume energy of the battery device. In this regard, by setting the minimum distance between the projections of the injection hole and the weak part on the same projection plane perpendicular to the first direction to be greater than or equal to 5mm and less than or equal to 50mm, the manufacturing yield rate, manufacturing efficiency and volume energy density of the battery cell and the battery device can be taken into account.

[0009] According to some embodiments of the present application, on the same projection plane perpendicular to the first direction, the minimum distance between the projection of the liquid injection hole and the projection of the weak portion is greater than or equal to 10 mm and less than or equal to 20 mm.

[0010] In the above scheme, by setting the minimum distance between the projections of the injection hole and the weak part on the same projection plane perpendicular to the first direction to be greater than or equal to 10 mm, the influence of the pressure generated during electrolyte injection on the weak part can be further reduced, and the risk of the battery cell being scrapped due to rupture of the weak part can be reduced. By setting the minimum distance between the projections of the injection hole and the weak part on the same projection plane perpendicular to the first direction to be less than or equal to 20 mm, the interference of the injection hole or the weak part on other structural parts can be effectively reduced, so that at the battery device level, the battery device structure is compact, which is conducive to the improvement of the volume energy of the battery device. In this regard, by setting the minimum distance between the projections of the injection hole and the weak part on the same projection plane perpendicular to the first direction to be greater than or equal to 10 mm and less than or equal to 20 mm, the manufacturing yield rate, manufacturing efficiency and volume energy density of the battery cell can be effectively taken into account.

[0011] According to some embodiments of the present application, the battery cell further includes a first electrode terminal and a second electrode terminal, the polarities of the first electrode terminal and the second electrode terminal are opposite, the first electrode terminal and the second electrode terminal are respectively arranged on the first wall, and the first electrode terminal and the second electrode terminal are arranged at intervals along the second direction, and the first direction and the second direction are perpendicular to each other.

[0012] In the above scheme, on the one hand, the first electrode terminal and the second electrode terminal are both arranged on the first wall, so that the first electrode terminal and the second electrode terminal utilize the space on the same side, which is beneficial to the improvement of the space utilization rate of the battery cell, thereby facilitating the improvement of the volume energy density of the battery device; on the other hand, by arranging the first electrode terminal and the second electrode terminal and the weak part on two wall parts opposite to each other, the impact of the weak part rupturing to release the internal pressure of the battery cell on the electrode terminals of the adjacent battery cells can be reduced, thereby reducing the risk of internal short circuit in the battery device, thereby improving the reliability of the battery device.

[0013] According to some embodiments of the present application, along the second direction, the liquid injection hole is located between the first electrode terminal and the second electrode terminal.

[0014] In the above scheme, the injection hole is arranged between the first electrode terminal and the second electrode terminal, so that the distance between the injection hole and the first electrode terminal, and the distance between the injection hole and the second electrode terminal are appropriate, thereby reducing the risk of electrolyte adhering to the first electrode terminal or the second electrode terminal during the electrolyte injection process due to the distance between the injection hole and the first electrode terminal being too close, or the distance between the injection hole and the second electrode terminal being too close, causing production personnel to misjudge that the battery cell is leaking and affect the production rhythm, thereby improving the production rhythm of the battery cell, and further contributing to the improvement of the manufacturing efficiency of the battery device.

[0015] According to some embodiments of the present application, along the second direction, a distance between the liquid injection hole and the first electrode terminal is equal to a distance between the liquid injection hole and the second electrode terminal.

[0016] In the above scheme, along the second direction, by centeredly arranging the injection hole between the first electrode terminal and the second electrode terminal, the distance between the injection hole and the first electrode terminal, and the distance between the injection hole and the second electrode terminal are appropriate, thereby reducing the risk of the electrolyte adhering to the electrode terminals during the injection process and affecting the production cycle.

[0017] According to some embodiments of the present application, along the second direction, the distance between the liquid injection hole and the first electrode terminal is greater than the distance between the liquid injection hole and the second electrode terminal.

[0018] In the above scheme, along the second direction, by setting the injection hole farther away from the first electrode terminal, the risk of electrolyte adhesion to the first electrode terminal can be effectively reduced. At the same time, under the condition that the injection hole and the weak part are staggered, the weak part can be centered between the first electrode terminal and the second electrode terminal, which is conducive to the weak part rupturing under the internal pressure of the battery cell and timely releasing the internal pressure of the battery cell, thereby facilitating the improvement of the reliability of the battery cell and further improving the reliability of the battery device.

[0019] According to some embodiments of the present application, the first wall has a first edge and a second edge in the third direction. Along the third direction, the distance between the injection hole and the first edge is equal to the distance between the injection hole and the second edge. The first direction, the second direction and the third direction are perpendicular to each other.

[0020] In the above solution, along the third direction, by centeredly arranging the injection hole between the first edge and the second edge, the distance between the injection hole and the first edge, and the distance between the injection hole and the second edge are appropriate, thereby reducing the risk of the electrolyte adhering to the two opposite walls of the battery cell along the third direction during the injection process and affecting the production rhythm.

[0021] According to some embodiments of the present application, the first wall has a first edge and a second edge in the third direction. Along the third direction, the distance between the injection hole and the first edge is greater than the distance between the injection hole and the second edge. The first direction, the second direction and the third direction are perpendicular to each other.

[0022] In the above scheme, along the third direction, by setting the injection hole farther away from the first edge, and under the condition that the injection hole and the weak part are staggered, the weak part can be centered on the second wall along the third direction, thereby facilitating the weak part to rupture under the internal pressure of the battery cell and timely release the internal pressure of the battery cell, thereby facilitating the improvement of the reliability of the battery cell and further improving the reliability of the battery device.

[0023] According to some embodiments of the present application, along the second direction, the distance between the injection hole and the first electrode terminal is greater than or equal to 40 mm, and the distance between the injection hole and the second electrode terminal is greater than or equal to 40 mm.

[0024] In the above scheme, along the second direction, by setting the distance between the injection hole and the first electrode terminal to be greater than or equal to 40 mm, the risk of the electrolyte adhering to the first electrode terminal and affecting the production cycle during injection can be effectively reduced; along the second direction, by setting the distance between the injection hole and the second electrode terminal to be greater than or equal to 40 mm, the risk of the electrolyte adhering to the second electrode terminal and affecting the production cycle during injection can be effectively reduced.

[0025] According to some embodiments of the present application, the injection hole includes a first hole segment and a second hole segment, the first hole segment and the second hole segment are arranged in a direction from the first wall to the second wall, and the aperture of the first hole segment is larger than the aperture of the second hole segment.

[0026] In the above scheme, by setting the injection hole as a stepped hole shape and setting the aperture of the first hole segment located on the outside to be larger than the aperture of the second hole segment located on the inside, it is convenient for the injection equipment to inject liquid into the interior of the shell through the injection hole, providing a larger space for the injection of electrolyte, thereby reducing the risk of electrolyte splashing outward, which is beneficial to improving the production rhythm of battery cells and further improving the manufacturing efficiency of battery devices.

[0027] According to some embodiments of the present application, the hole diameter of the first hole section is greater than or equal to 4 mm and less than or equal to 10 mm.

[0028] In the above scheme, by setting the aperture of the first hole segment to be greater than or equal to 4 mm, a larger space can be effectively provided for the electrolyte, reducing the risk of electrolyte splashing outward, which is beneficial to improving the production rhythm of battery cells; by setting the first hole segment to be less than or equal to 10 mm, the space occupied by the injection hole on the first wall can be reduced, thereby facilitating the layout of other structural parts, making the battery device structure compact, and improving the volume energy density of the battery device.

[0029] According to some embodiments of the present application, the center of the weak portion coincides with the center of the second wall.

[0030] In the above solution, by setting the center of the weak portion to coincide with the center of the second wall, the internal pressure of the battery cell can be effectively applied to the weak portion, so that the weak portion ruptures more promptly to release the internal pressure of the battery cell, thereby reducing the risk of battery cell explosion, and improving the reliability of the battery cell and the reliability of the battery device.

[0031] According to some embodiments of the present application, on the same projection plane perpendicular to the first direction, the projection of the liquid injection hole and the projection of the pressure relief area do not overlap with each other.

[0032] In the above scheme, in some embodiments, a pressure relief zone can be formed at the location where the weak portion is located. By setting the projections of the injection hole and the pressure relief zone on the same projection plane perpendicular to the first direction to be non-overlapping, the pressure generated when the electrolyte is injected into the interior of the shell through the injection hole can be effectively reduced. The impact on the pressure relief zone caused by this pressure is reduced, resulting in the pressure relief zone, that is, the weak portion being damaged and ruptured, resulting in the risk of the battery cell being scrapped, so that the battery cell has a higher yield during the manufacturing process, thereby facilitating the improvement of the manufacturing efficiency of the battery cell, and further facilitating the improvement of the manufacturing efficiency of the battery device.

[0033] According to some embodiments of the present application, the second wall is provided with a notched groove, the bottom wall of the notched groove is a weak portion, and the notched groove defines a pressure relief area.

[0034] In the above solution, by providing a notched groove on the second wall and forming the bottom wall of the notched groove into a weakened portion, the second wall can be cracked along the notched groove under the internal pressure of the battery cell to open a pressure relief zone, thereby releasing the internal pressure of the battery cell, thereby improving the reliability of the battery cell. Furthermore, the notched groove is simple to manufacture, and using the notched groove to form a weakened portion is beneficial for improving the manufacturing efficiency of the battery cell.

[0035] According to some embodiments of the present application, the scored groove includes a first groove segment, a second groove segment and a third groove segment, the first groove segment and the third groove segment are arranged opposite to each other along the second direction, the second groove segment is located between the first groove segment and the third groove segment and connects the first groove segment and the third groove segment, the first groove segment, the second groove segment and the third groove segment jointly define a pressure relief area, and the first direction and the second direction are perpendicular to each other.

[0036] In the above solution, the scored groove structure is simple, comprising a first groove section, a third groove section, and a second groove section connecting the first and third groove sections. When the internal pressure of the battery cell expands to a certain extent, the second wall can split along the first, second, and third groove sections, thereby providing the battery cell with a larger pressure relief area, facilitating the rapid release of internal pressure, thereby improving the reliability of the battery cell and, in turn, the reliability of the battery device.

[0037] According to some embodiments of the present application, on the same projection plane perpendicular to the first direction, the projection of the liquid injection hole is located between the projection of the first groove segment and the projection of the third groove segment.

[0038] In the above scheme, on the same projection plane perpendicular to the first direction, by arranging the projection of the injection hole between the projection of the first groove segment and the projection of the second groove segment, on the one hand, the pressure generated during the electrolyte injection process can be reduced from directly acting on the groove bottom wall of the first groove segment and the groove bottom wall of the second groove segment, thereby causing the risk of the second wall to rupture during the battery cell manufacturing process; on the other hand, the space utilization rate of the injection hole and the weak part can be improved, so as to provide a larger space for other structural components of the battery device, which is beneficial to the spatial layout of other structural components of the battery device, and thus beneficial to the volume energy density of the battery device.

[0039] According to some embodiments of the present application, the scored groove includes an annular scored groove, and the annular scored groove is surrounded to form a pressure relief area.

[0040] In the above solution, the notched groove is annular to enclose a relatively large pressure relief area, so that the battery cell has a relatively large pressure relief area, so that the internal pressure of the battery cell can be quickly released, and the battery device has a relatively high reliability.

[0041] According to some embodiments of the present application, the annular scored groove includes a first straight segment, a second straight segment, a first arc segment, and a second arc segment. Along the third direction, the first straight segment and the second straight segment are arranged opposite each other. Along the second direction, the first arc segment and the second arc segment are arranged opposite each other. One end of the first straight segment and one end of the second straight segment are connected by the first arc segment, and the other end of the first straight segment and the other end of the second straight segment are connected by the second arc segment. The thickness of the groove bottom wall of the second straight segment, the thickness of the groove bottom wall of the first arc segment, and the thickness of the groove bottom wall of the second arc segment are all less than the thickness of the groove bottom wall of the first straight segment. The first direction, the second direction, and the third direction are mutually perpendicular.

[0042] In the above scheme, by setting the thickness of the second wall along the second straight segment, the first arc segment and the second arc segment to be smaller, when the internal pressure of the battery cell expands to a certain extent, the second wall can rupture along the second straight segment, the first arc segment and the second arc segment to quickly release the internal pressure of the battery cell, so that the battery device has higher reliability; at the same time, because the thickness of the bottom wall of the groove of the first straight segment is larger, the pressure relief area can be retained in the second wall at the position of the first straight segment, reducing the risk of the weak part of the rectification being impacted by pressure to the adjacent battery cell or other structural parts of the battery device, causing damage to the adjacent battery cell or other structural parts of the battery device, thereby improving the reliability of the battery device.

[0043] According to some embodiments of the present application, the scored groove further includes a fourth groove segment and a fifth groove segment, the fourth groove segment and the fifth groove segment are located in the pressure relief zone, and the fourth groove segment and the fifth groove segment are respectively arc-shaped. Along the third direction, the fourth groove segment and the fifth groove segment are arranged opposite each other, and the outer edge of the fourth groove segment is tangent to the outer edge of the fifth groove segment. The thickness of the groove bottom wall of the second straight line segment, the thickness of the groove bottom wall of the first arc segment, and the thickness of the groove bottom wall of the second arc segment are all less than or equal to the thickness of the groove bottom wall of the fourth groove segment. The thickness of the groove bottom wall of the second straight line segment, the thickness of the groove bottom wall of the first arc segment, and the thickness of the groove bottom wall of the second arc segment are all less than or equal to the thickness of the groove bottom wall of the fifth groove segment.

[0044] In the above scheme, the scored groove also includes a fourth groove segment and a fifth groove segment, and the fourth groove segment and the fifth groove segment are located in the pressure relief area, which can reduce the structural strength of the portion of the second wall located in the pressure relief area, so that when the weak portion is affected by the internal pressure of the battery cell, it can facilitate the rupture of the portion where the pressure relief area is located, so as to quickly release the internal pressure of the battery cell, thereby effectively improving the reliability of the battery device.

[0045] According to some embodiments of the present application, a portion where the outer edge of the fourth slot segment and the outer edge of the fifth slot segment are tangent to each other coincides with the center of the second wall.

[0046] In the above scheme, by setting the tangent parts of the outer edge sides of the fourth groove segment and the outer edge sides of the fifth groove segment to coincide with the center of the second wall, the internal pressure of the battery cell can be uniformly applied to the annular score groove through the fourth groove segment and the fifth groove segment, thereby facilitating the rupture of the second wall along the second straight line segment, the first arc segment and the second arc segment, so as to quickly release the internal pressure of the battery cell, thereby making the battery device have higher reliability.

[0047] According to some embodiments of the present application, along the second direction, one end of the first straight line segment is connected to one end of the fourth slot segment, and the other end of the first straight line segment is connected to the other end of the fourth slot segment; along the second direction, one end of the second straight line segment is connected to one end of the fifth slot segment, and the other end of the second straight line segment is connected to the other end of the fifth slot segment.

[0048] In the above scheme, by extending the two ends of the fourth groove segment to the first straight segment and extending the two ends of the fifth groove segment to the second straight segment, the internal pressure of the battery cell can be effectively applied to the annular score groove, thereby facilitating the rupture of the annular score groove to release the internal pressure of the battery cell, thereby facilitating the improvement of the reliability of the battery device.

[0049] According to some embodiments of the present application, on the same projection plane perpendicular to the first direction, the projection of the liquid injection hole is located in the area enclosed by the projection of the first arc segment, the projection of the fourth groove segment, and the projection of the fifth groove segment.

[0050] In the above scheme, on the same projection plane perpendicular to the first direction, by arranging the projection of the injection hole in the area enclosed by the projection of the first arc segment, the projection of the fourth groove segment and the projection of the fifth groove segment, on the one hand, the pressure generated during the electrolyte injection process can be reduced from directly acting on the notched groove, thereby causing the risk of the second wall to rupture during the battery cell manufacturing process; on the other hand, the space utilization rate of the injection hole and the weak part can be improved, thereby providing a larger space for other structural components of the battery device, which is beneficial to the spatial layout of other structural components of the battery device, and thus beneficial to the volume energy density of the battery device.

[0051] According to some embodiments of the present application, the weak portion is integrally formed on the second wall.

[0052] In the above solution, the weak portion can be formed on the second wall through an integrated molding process, which can reduce the manufacturing steps of the battery cell, effectively improve the manufacturing efficiency of the battery cell, and further contribute to improving the manufacturing efficiency of the battery device.

[0053] According to some embodiments of the present application, the second wall includes a wall body and a pressure relief member, the weak portion is formed in the pressure relief member, the wall body has a first through hole extending along a first direction, and the pressure relief member is connected to the wall body and closes the first through hole.

[0054] In the above scheme, the second wall includes a wall body and a pressure relief piece, and the weak portion is formed in the pressure relief piece. By connecting the pressure relief piece with the wall body, the first through hole of the wall body can be reduced in closure and a weak portion can be set on the second wall, so that the battery cell has a pressure relief function, which is beneficial to improving the reliability of the battery cell.

[0055] According to some embodiments of the present application, the projected area of ​​the pressure relief member on the projection plane perpendicular to the first direction is greater than or equal to 200 mm 2 , and less than or equal to 2000mm 2 .

[0056] In the above solution, by setting the projection area of ​​the pressure relief member along the first direction to be greater than or equal to 200mm 2 , which can make the battery cell have a larger pressure relief area and pressure relief rate, thereby making the battery cell have higher reliability; by setting the projection area of ​​the pressure relief member along the first direction to be less than or equal to 2000mm 2 , which can reduce the interference of the pressure relief component with other structural components of the battery device and provide a larger space for other structural components, so as to make the battery device compact and facilitate the improvement of the volume energy density of the battery device.

[0057] In a second aspect, some embodiments of the present application provide a battery device, comprising any one of the battery cells provided in the first aspect.

[0058] In a third aspect, some embodiments of the present application provide an electrical device, the electrical device comprising the battery cell provided in the first aspect and / or the battery device provided in the third aspect. The battery cell is used to provide electrical energy.

[0059] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. 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 relevant drawings can be obtained based on these drawings without paying any creative work.

[0061] Figure 1 A schematic diagram of a vehicle in some embodiments of the present application;

[0062] Figure 2 This is a three-dimensional exploded view of a battery device in some embodiments of the present application;

[0063] Figure 3A three-dimensional diagram of a battery cell in some embodiments of the present application;

[0064] Figure 4 This is a schematic structural diagram of a battery cell in some embodiments of the present application;

[0065] Figure 5 for Figure 3 Sectional view from the AA direction;

[0066] Figure 6 Graph showing the positional relationship between the projection of the liquid injection hole and the projection of the weak portion on the same projection plane perpendicular to the first direction in some embodiments of the present application;

[0067] Figure 7 A top view of a battery cell in some embodiments of the present application;

[0068] Figure 8 A top view of a battery cell in some other embodiments of the present application;

[0069] Figure 9 for Figure 5 Enlarged view of point B in the middle;

[0070] Figure 10 Schematic diagram of the second wall and the weak portion in some embodiments of the present application;

[0071] Figure 11 Schematic diagram of the second wall and the scored groove in some embodiments of the present application;

[0072] Figure 12 This is a schematic diagram of the wall body and the pressure relief member in some embodiments of the present application.

[0073] Icons: 1000-vehicle; 100-battery device; 200-controller; 300-motor; 10-battery cell; 20-housing; 21-first housing portion; 22-second housing portion; 11-housing; 110-first wall; 1100-first edge; 1101-second edge; 112-second wall; 1120-wall body; 1121-pressure relief member; 1122-first through hole; 113-third wall; 114-fourth wall; 115-fifth wall; 116-sixth wall; 12-liquid injection hole; 12a closure member; 1 20-first hole section; 121-second hole section; 13-electrode assembly; 14-weak portion; 140-notched groove; 141-first groove section; 142-second groove section; 143-third groove section; 140a-annular notched groove; 144-first straight line segment; 145-second straight line segment; 146-first arc segment; 147-second arc segment; 148-fourth groove section; 149-fifth groove section; 15-pressure relief area; 16-first electrode terminal; 17-second electrode terminal; z-first direction; y-second direction; x-third direction. DETAILED DESCRIPTION

[0074] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0075] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" 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-secondary relationship.

[0076] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments.

[0077] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0078] The term "and / or" in this application simply describes an association between related objects, indicating that three possible relationships exist. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this application generally indicates that the related objects are in an "or" relationship.

[0079] In the embodiments of this application, the same reference numerals represent the same components, and for the sake of brevity, detailed descriptions of the same components in different embodiments are omitted. It should be understood that the thickness, length, width, and other dimensions of the various components in the embodiments of this application, as well as the overall thickness, length, width, and other dimensions of the integrated device shown in the drawings are merely illustrative and should not constitute any limitation on this application.

[0080] The term "plurality" used in this application refers to two or more (including two).

[0081] In the embodiment of the present application, the battery cell may be a secondary battery. A secondary battery refers to a battery cell that can be continuously used by activating active materials by charging after the battery cell is discharged.

[0082] The battery cells can be lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-hydrogen batteries, nickel-cadmium batteries, lead-acid batteries, etc., which are not limited in the embodiments of the present application.

[0083] A battery cell typically includes an electrode assembly. This assembly includes a positive electrode, a negative electrode, and a separator. During the charge and discharge process of a battery cell, active ions (such as lithium ions) are inserted and removed between the positive and negative electrodes. The separator, placed between the positive and negative electrodes, prevents short circuits between the positive and negative electrodes while allowing the active ions to pass through.

[0084] In some embodiments, the positive electrode may be a positive electrode sheet, which may include a positive electrode current collector and a positive electrode active material disposed on at least one surface of the positive electrode current collector.

[0085] In some embodiments, the negative electrode may be a negative electrode sheet, and the negative electrode sheet may include a negative electrode current collector.

[0086] In some embodiments, the electrode assembly further includes a separator disposed between the positive electrode and the negative electrode.

[0087] In some embodiments, the separator is a separator membrane. There are many types of separator membranes, and any known separator membrane with a porous structure having good chemical stability and mechanical stability can be selected.

[0088] In some embodiments, the battery cell further includes an electrolyte, which acts as a conductor of ions between the positive and negative electrodes. The electrolyte can be liquid, gel, or solid. Liquid electrolytes include an electrolyte salt and a solvent.

[0089] In some embodiments, the electrode assembly is a wound structure, wherein the positive electrode sheet and the negative electrode sheet are wound into the wound structure.

[0090] In some embodiments, the electrode assembly is a laminate structure.

[0091] As an example, multiple positive electrode sheets and multiple negative electrode sheets can be provided respectively, and the multiple positive electrode sheets and the multiple negative electrode sheets can be alternately stacked.

[0092] As an example, a plurality of positive electrode sheets may be provided, and the negative electrode sheet may be folded to form a plurality of stacked folded segments, with a positive electrode sheet being sandwiched between adjacent folded segments.

[0093] As an example, both the positive electrode sheet and the negative electrode sheet are folded to form a plurality of stacked folded segments.

[0094] As an example, a plurality of separators may be provided, each of which is disposed between any adjacent positive electrode sheets or negative electrode sheets.

[0095] As an example, the separator may be provided continuously, and may be provided between any adjacent positive electrode sheets or negative electrode sheets by folding or winding.

[0096] In some embodiments, the shape of the electrode assembly can be cylindrical, flat, or polygonal.

[0097] In some embodiments, the electrode assembly is provided with tabs that can conduct current from the electrode assembly. The tabs include a positive tab and a negative tab.

[0098] In some embodiments, a battery cell may include a housing. The housing is used to encapsulate components such as the electrode assembly and the electrolyte. The housing may be a steel housing, an aluminum housing, a plastic housing (e.g., polypropylene), a composite metal housing (e.g., a copper-aluminum composite housing), or an aluminum-plastic film.

[0099] As an example, the battery cells may be cylindrical, prismatic, soft-pack or other shaped battery cells. Prismatic battery cells include but are not limited to square-shell, blade-shaped, and polygonal batteries, such as hexagonal batteries.

[0100] The battery apparatus mentioned in the embodiments of the present application may include one or more battery cell assemblies for providing voltage and capacity. The battery cell assembly may include multiple battery cells, which are connected in series, parallel, or hybrid via a busbar.

[0101] In some embodiments, a battery cell assembly is typically formed by arranging multiple battery cells. For example, the battery cell assembly may be a battery module, which is a battery module formed by arranging and securing multiple battery cells to form a single module. For example, a battery module may be formed by bundling multiple battery cells using cable ties.

[0102] In some embodiments, the battery device may be a battery pack, which includes a case and one or more battery cell assemblies, wherein the battery cell assemblies are housed in the case.

[0103] As an example, the battery cell assembly may be a battery module, and the battery cell assembly may be accommodated in the box by fixing the battery module in the box.

[0104] As an example, the battery cell assembly may also be housed in the box by directly fixing the plurality of battery cells to the box.

[0105] As an example, the housing may include a first housing and a second housing. The first housing and the second housing engage to form an enclosed space within the housing to house the battery cell assembly. Enclosed here means covered or closed, and can be either sealed or unsealed. The first housing may be a top cover or a bottom plate.

[0106] As an example, the box may include a top cover, a frame, and a bottom plate, wherein the top cover and the bottom plate are respectively connected to the frame to form a closed space inside the box to accommodate the battery cell assembly.

[0107] As an example, the box body can be used as a part of the chassis structure of the vehicle. For example, the top cover of the box body can become at least a part of the floor of the vehicle, or the frame of the box body can become at least a part of the crossbeam and longitudinal beam of the vehicle.

[0108] In some embodiments, the battery device may refer to an energy storage device, which includes a box with a door on at least one side. The energy storage device includes an energy storage container, an energy storage cabinet, etc.

[0109] As an example, a battery device includes a beam assembly and a battery cell assembly. The beam assembly may include mutually arranged mounting beams and installation beams. The installation beams are used to mount and secure the battery cell assembly, and the mounting beams are used to mount the battery on the main body of the electrical device so that the battery can supply power to the main body of the electrical device. In some embodiments, the beam assembly may be a part of the structural component of the box.

[0110] Batteries, with their outstanding advantages such as high energy density, low environmental pollution, high power density, long service life, wide adaptability, and low self-discharge coefficient, are a crucial component of today's new energy development. The development of battery technology requires simultaneous consideration of multiple design factors, including cycle life, discharge capacity, charge and discharge rate, and other performance parameters. Furthermore, the manufacturing efficiency of the battery cells must be considered.

[0111] In battery technology, a battery cell generally includes a shell, an electrode assembly, and an electrolyte. The shell and the electrolyte are arranged inside the shell, and the electrolyte plays the role of conducting ions between the positive and negative electrodes. Generally, an injection hole is provided on the shell, and the injection hole is used to inject electrolyte into the interior of the shell. Exemplarily, the shell has a first wall and a second wall opposite to each other, the first wall can be a top wall, and the second wall can be a bottom wall. The injection hole can be provided with an injection hole. During the charge and discharge process, gas is generated inside the battery cell due to electrochemical reactions. As the number of charge and discharge cycles of the battery cell increases, the internal pressure of the battery cell increases, and there is a risk of thermal runaway. In order to reduce the risk of thermal runaway, in related technologies, the wall of the shell is also provided with a weak portion. When the internal pressure of the battery cell reaches a certain level, the second wall can rupture along the weak portion to release the internal pressure of the battery cell. At present, in some battery cells, the weak portion is provided on the second wall, which is arranged opposite to the injection hole, and the two are at least partially arranged opposite each other. During the manufacturing process of some battery cells, there is a problem that the pressure generated during the electrolyte injection process acts on the weak part, causing the second wall to rupture and the battery cell to be scrapped, resulting in a low battery cell manufacturing yield and affecting the manufacturing efficiency of the battery cell and battery device.

[0112] In view of this, in order to improve the problem that the pressure generated during the electrolyte injection process causes the second wall to rupture along the weak portion, affecting the manufacturing efficiency of the battery cell and the manufacturing efficiency of the battery device, some embodiments of the present application provide a battery cell, which includes a shell and an electrode assembly. The shell has a first wall and a second wall opposite to each other along a first direction z, and the first wall has an injection hole, which is used to inject electrolyte into the interior of the shell. The electrode assembly is arranged inside the shell. The second wall is formed with a weak portion and a pressure relief area, and the second wall is configured to be able to rupture along the weak portion to open the pressure relief area. On the same projection plane perpendicular to the first direction z, the projection of the injection hole and the projection of the weak portion do not overlap with each other.

[0113] In the above scheme, on the one hand, the injection hole and the weak part are respectively provided on the first wall and the second wall opposite to each other of the shell. Compared with the scheme in which the injection hole and the weak part are provided on the same wall, the interference of the weak part or the injection hole on other structural parts can be reduced, so as to improve the space utilization rate of other structural parts at the battery device level, for example, the interference of the weak part or the injection hole on the external convergence component is reduced, thereby facilitating the improvement of the volume energy density of the battery device; on the other hand, by arranging the projections of the injection hole and the weak part on the same projection plane perpendicular to the first direction z to not overlap with each other, the pressure generated when the electrolyte is injected into the shell by the injection hole can be effectively reduced to impact the weak part, causing the weak part to be damaged and ruptured, resulting in the risk of the battery cell being scrapped, so that the battery cell has a higher yield rate during the manufacturing process, thereby facilitating the improvement of the battery cell manufacturing efficiency, and further facilitating the improvement of the battery device manufacturing efficiency.

[0114] The technical solutions described in the embodiments of the present application are applicable to batteries and electrical devices using batteries.

[0115] Electrical devices may include vehicles, mobile phones, portable devices, laptop computers, ships, spacecraft, electric toys, and electric tools, etc. Vehicles may include new energy vehicles, which may include pure electric vehicles, hybrid electric vehicles, or extended-range vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include fixed or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Electric tools include metal cutting electric tools, grinding electric tools, assembly electric tools, and railway electric tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. The embodiments of the present application do not impose any special restrictions on the above-mentioned electrical devices.

[0116] For the convenience of description, the following embodiments are described by taking a vehicle as an example of an electrical device.

[0117] Figure 1 Schematic diagram of a vehicle 1000 in some embodiments of the present application.

[0118] A controller 200, a motor 300 and a battery device 100 may be provided inside the vehicle 1000, and the controller 200 is used to control the battery device 100 to power the motor 300. For example, a battery may be provided at the bottom, front or rear of the vehicle 1000. The battery device 100 may be used to power the vehicle 1000. For example, the battery device 100 may be used as an operating power source for the vehicle 1000, for the circuit system of the vehicle 1000, for example, for the working power requirements during the start-up, navigation and operation of the vehicle 1000. In another embodiment of the present application, the battery device 100 may not only be used as an operating power source for the vehicle 1000, but may also be used as a driving power source for the vehicle 1000, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1000.

[0119] See Figure 2 , Figure 2 1 is a perspective exploded view of the battery device 100 in some embodiments of the present application.

[0120] The battery device 100 includes a battery cell 10 and a housing 20, with the battery cell 10 housed within the housing 20. The housing 20 is used to provide a storage space for the battery cell 10, and the housing 20 can have various structures. In some embodiments, the housing 20 can include a first housing portion 21 and a second housing portion 22, which cover each other and together define a storage space for the battery cell 10. The second housing portion 22 can be a hollow structure with one end open, and the first housing portion 21 can be a plate-like structure, with the first housing portion 21 covering the open side of the second housing portion 22, so that the first housing portion 21 and the second housing portion 22 together define a storage space. The first housing portion 21 and the second housing portion 22 can also be hollow structures with one end open, with the open side of the first housing portion 21 covering the open side of the second housing portion 22. Of course, the box body 20 formed by the first box body portion 21 and the second box body portion 22 can be in various shapes, such as a cylinder, a cuboid, etc.

[0121] In the battery device 100 , there may be one or more battery cells 10 , and each battery cell 10 may be fixed to the case 20 via a connector (such as a bolt), or each battery cell 10 may be fixed to the case 20 by bonding.

[0122] In some embodiments, the battery cells 10 in the box 20 may be electrically connected via a busbar component, so that the battery cells 10 in the box 20 are connected in series, in parallel, or in mixed series.

[0123] For example, a plurality of battery cell assemblies are provided in the housing 20. Each battery cell assembly includes a plurality of stacked battery cells 10. The plurality of battery cells 10 are connected in series via a busbar. In some embodiments, the plurality of battery cell assemblies can be connected in series via a busbar.

[0124] See Figure 3-Figure 5 , Figure 3 This is a three-dimensional diagram of a battery cell 10 in some embodiments of the present application. Figure 4 This is a schematic structural diagram of a battery cell 10 in some embodiments of the present application. Figure 5 for Figure 3In the cross-sectional view taken along the AA direction, some embodiments of the present application provide a battery cell 10, which includes a shell 11 and an electrode assembly 13. The shell 11 has a first wall 110 and a second wall 112 opposite to each other along a first direction z. The first wall 110 has an injection hole 12, which is used to inject electrolyte into the interior of the shell 11. The electrode assembly 13 is disposed inside the shell 11. The second wall 112 is formed with a weak portion 14 and a pressure relief area 15. The second wall 112 is configured to be able to crack along the weak portion 14 to open the pressure relief area 15. On the same projection plane perpendicular to the first direction z, the projection of the injection hole 12 and the projection of the weak portion 14 do not overlap with each other.

[0125] In some embodiments, the battery cell 10 includes a housing 11 and an electrode assembly 13. The electrode assembly 13 and the electrolyte can be enclosed in the enclosed space of the housing 11. The housing 11 can be a square housing, a cylindrical housing, or a flat housing. Optionally, the housing 11 includes multiple walls that are interconnected and enclosed to form a housing cavity for accommodating the electrode assembly 13. For example, see Figure 3 and Figure 4 The housing 11 includes a first wall 110 and a second wall 112 that are opposite to each other, a third wall 113 and a fourth wall 114 that are opposite to each other, and a fifth wall 115 and a sixth wall 116 that are opposite to each other. The first wall 110, the second wall 112, the third wall 113, the fourth wall 114, the fifth wall 115, and the sixth wall 116 are interconnected and together enclose a receiving cavity. For example, the housing 11 is cylindrical and includes the first wall 110 and the second wall 112 that are opposite to each other, and a peripheral wall disposed between the first wall 110 and the second wall 112. One end of the peripheral wall is disposed around the edge of the first wall 110, and the other end of the peripheral wall is disposed around the edge of the second wall 112.

[0126] In some embodiments, the housing 11 may be an integrally formed structure, or some of the walls of the housing 11 may be an integrally formed structure, or the walls of the housing 11 may be separate structures connected to each other by welding, bonding, riveting, or screws. For example, the housing 11 includes a shell and a first wall 110, the shell includes a second wall 112, the shell has a first opening, the electrode assembly 13 may be placed into the shell through the first opening, the first wall 110 is connected to the shell 11 and closes the first opening; or the shell 11 includes a shell, a first wall 110, and a second wall 112, the shell has a first opening and a second opening opposite to each other, the first wall 110 is connected to the shell and closes the first opening, and the second wall 112 is connected to the shell and closes the second opening.

[0127] In some embodiments, the housing 11 may be made of metal, such as aluminum, steel, composite metal, etc. Alternatively, in other embodiments, the housing 11 may be made of non-metallic material, such as plastic.

[0128] In some embodiments, the materials of the various walls of the housing 11 may be the same or different. For example, the first wall 110, the second wall 112, the third wall 113, the fourth wall 114, the fifth wall 115, and the sixth wall 116 are all made of steel; or, the first wall 110 is made of aluminum, and the second wall 112, the third wall 113, the fourth wall 114, the fifth wall 115, and the sixth wall 116 are all made of steel.

[0129] In some embodiments, the first direction z may be the height direction of the battery cell 10, see Figure 3 and Figure 4 The first wall 110 and the second wall 112 may be opposite to each other along the height direction of the battery cell 10. In some usage scenarios, the first direction z may be parallel to the direction of gravity, the first wall 110 may be the top wall, and the second wall 112 may be the bottom wall. In other usage scenarios, the height direction of the battery cell 10 may be parallel to the direction of gravity, the second wall 112 may be the top wall, and the first wall 110 may be the bottom wall. In other usage scenarios, the height direction of the battery cell 10 may also be parallel to the horizontal direction.

[0130] In some embodiments, the number of the electrode assembly 13 may be one or more. Optionally, the battery cell 10 includes two electrode assemblies 13 , which are stacked in the housing 11 .

[0131] In some embodiments, the battery cell 10 further includes an electrode terminal, which is provided on the wall of the outer shell 11, and the electrode terminal is used to connect the tabs of the electrode assembly 13 and an external busbar component (such as a bar) to realize the input and output of electrical energy of the battery cell 10. Optionally, the tabs of the electrode assembly 13 are welded to the electrode terminals. Optionally, the tabs of the electrode assembly 13 are electrically connected to the electrode terminals through an adapter. In some embodiments, the electrode terminal can be a cylindrical structure, or a polygonal prism structure, or can be a composite structure of a cylindrical and polygonal prism. In some embodiments, the electrode terminal is made of a metal material, for example, aluminum, copper, iron, steel, an alloy or a composite metal.

[0132] In some embodiments, the electrode terminals include a first electrode terminal 16 and a second electrode terminal 17 of opposite polarity, for example, the first electrode terminal 16 is a positive electrode terminal, and the second electrode terminal 17 is a negative electrode terminal. The first electrode terminal 16 is electrically connected to the electrode tab of the corresponding polarity, and the second electrode terminal 17 is electrically connected to the electrode tab of the corresponding polarity. In some embodiments, the first electrode terminal 16 and the second electrode terminal 17 can be disposed on the same wall of the housing 11, such as the first wall 110, the second wall 112, the third wall 113, the fourth wall 114, the fifth wall 115, or the sixth wall 116. For example, the first electrode terminal 16 and the second electrode terminal 17 are spaced apart from each other on the first wall 110. In other embodiments, the first electrode terminal 16 and the second electrode terminal 17 can be disposed on different walls of the housing 11, for example, the first electrode terminal 16 is disposed on the first wall 110, and the second electrode terminal 17 is disposed on the second wall 112.

[0133] The injection hole 12 is a through-hole structure provided in the first wall 110 and penetrates the first wall 110 along the thickness direction of the first wall 110. The injection hole 12 is used to inject electrolyte, such as electrolyte solution, into the housing 11.

[0134] In some embodiments, the injection hole 12 can be a circular hole, a square hole, a polygonal hole or a through hole structure of other shapes.

[0135] For example, when assembling the battery cell 10, the electrode assembly 13 can be placed inside the housing through the first opening. The first wall 110 is connected to the housing to cover the first opening, thereby placing the electrode assembly 13 in a closed space. Finally, the electrolyte is injected into the closed space through the injection hole 12 in the first wall 110, and the injection hole 12 is sealed. In some embodiments, the battery cell 10 further includes a sealing member 12a, which is used to seal the injection hole 12. The sealing member 12a can include a sealing nail, a threaded nail, a glue nail, etc.

[0136] In some embodiments, when assembling the battery cell 10 , electrolyte can be injected into the injection hole 12 by an injection device. For example, the injection device includes an injection head, which is aligned with or inserted into the injection hole 12 to inject electrolyte of a certain pressure into the shell 11 .

[0137] See Figure 4 The second wall 112 is formed with a weak portion 14 and a pressure relief area 15. The structural strength of the weak portion 14 is lower than that of other parts of the second wall 112. Therefore, when the internal pressure of the battery cell 10 increases to a certain level, the second wall 112 can be cracked along the weak portion 14, so that the pressure relief area 15 is opened, thereby connecting the interior of the shell 11 with the outside world, and the pressure or substance inside the shell 11 can be released through the opened pressure relief area 15.

[0138] In some embodiments, the weak portion 14 can be formed directly or indirectly on the second wall 112. Optionally, the weak portion 14 is integrally formed on the second wall 112, for example, the weak portion 14 is a notch structure, a recessed structure or other weak structure formed on the second wall 112. Optionally, the weak portion 14 can be formed on the second wall 112 by processes such as die casting, turning, and stamping. Optionally, the weak portion 14 is first formed on other structural parts, and the other structural parts are then integrated into the second wall 112. For example, the second wall 112 includes a wall body 1120 and a pressure relief member 1121, the wall body 1120 is formed with a first through hole 1122, and the pressure relief member 1121 is integrally formed with the weak portion 14, for example, the weak portion 14 is a notch structure, a recessed structure or other weak structure formed on the pressure relief member 1121, and the pressure relief member 1121 is connected to the wall body 1120 and closes the first through hole 1122. Optionally, the weak portion 14 can be formed on the pressure relief member 1121 by processes such as die casting, turning, and stamping. In some embodiments in which the second wall 112 includes a wall body 1120 and a pressure relief member 1121, the material of the wall body 1120 and the material of the pressure relief member 1121 can be the same or different. For example, the wall body 1120 can be made of steel and the pressure relief member 1121 can be made of aluminum, or the wall body 1120 can be made of aluminum and the pressure relief member 1121 can be made of aluminum. It should be noted that the connection between the wall body 1120 and the pressure relief member 1121 can be various, including but not limited to bonding, welding, riveting, screw connection, or other connection methods. Optionally, the second wall 112 includes a wall body 1120 , the structural strength of the wall body 1120 is greater than the structural strength of the weak portion 14 , a first through hole 1122 is formed in the wall body 1120 , and the weak portion 14 is connected to the wall body 1120 and closes the first through hole 1122 .

[0139] The phrase "the projection of the injection hole 12 and the projection of the weak portion 14 on the same projection plane perpendicular to the first direction z do not overlap" can be understood as meaning that the injection hole 12 and the weak portion 14 do not overlap in the line of sight from the first wall 110 to the second wall 112. Alternatively, it can be understood as meaning that the projection of the injection hole 12 onto the second wall 112 along the direction from the first wall 110 to the second wall 112 does not interfere with the weak portion 14. For example, if the weak portion 14 is at least part of a notch formed on the second wall 112, the projections of the injection hole 12 and the notch on the same projection plane perpendicular to the first direction z are independent of each other, with a distance between them. During the assembly of the battery cell 10, electrolyte can be injected from the injection hole 12 into the outer casing 11 along the direction from the first wall 110 to the second wall 112. The resulting injection pressure does not need to pass through the weak portion 14. In other words, the injection pressure does not need to directly impact the weak portion 14 through the gap between the outer casing 11 and the electrode assembly 13, or through the gap within the electrode assembly 13 itself.

[0140] For example, see Figure 6 , Figure 6 : This is a positional relationship diagram of the projection of the injection hole 12 and the projection of the weak portion 14 on the same projection plane perpendicular to the first direction z in some embodiments of the present application. Figure 6 As shown, the same projection plane perpendicular to the first direction z is SS, the projection of the weak portion 14 is annular, the projection of the injection hole 12 is annular, the projection of the injection hole 12 does not overlap with the projection of the weak portion 14, and the projection of the injection hole 12 can be located in the inner ring of the annular projection of the weak portion 14.

[0141] In the above solution, on the one hand, the injection hole 12 and the weak portion 14 are respectively provided on the first wall 110 and the second wall 112 of the housing 11, which are opposite to each other. Compared with a solution in which the injection hole 12 and the weak portion 14 are provided on the same wall, the interference of the weak portion 14 or the injection hole 12 with other structural components can be reduced, thereby improving the space utilization of other structural components at the battery device 100 level. For example, the interference of the weak portion 14 or the injection hole 12 with external manifold components is reduced, thereby facilitating an improvement in the volumetric energy density of the battery device 100. On the other hand, by arranging the projections of the injection hole 12 and the weak portion 14 on the same projection plane perpendicular to the first direction z to not overlap with each other, the pressure generated by the injection hole 12 when injecting electrolyte into the interior of the housing 11 can be effectively reduced, thereby reducing the risk of the weak portion 14 being damaged or ruptured due to the pressure generated by the injection hole 12. This can cause the weak portion 14 to be scrapped, thereby ensuring a higher yield rate for the battery cells 10 during the manufacturing process, thereby facilitating an improvement in the manufacturing efficiency of the battery cells 10, and further facilitating an improvement in the manufacturing efficiency of the battery devices 10.

[0142] According to some embodiments of the present application, on the same projection plane perpendicular to the first direction z, the minimum distance between the projection of the liquid injection hole 12 and the projection of the weak portion 14 is greater than or equal to 5 mm and less than or equal to 50 mm.

[0143] On the same projection plane perpendicular to the first direction z, the projection of the injection hole 12 and the projection of the weak portion 14 are spaced apart from each other, and there is a distance between them, and the minimum distance between them is greater than or equal to 5 mm. Figure 6 For example, on the same projection plane SS perpendicular to the first direction z, the minimum distance w between the projected outer periphery of the liquid injection hole 12 and the projected inner periphery of the weak portion 14 can be 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm…19 mm, 20 mm, 21 mm, 22 mm…45 mm, 46 mm, 47 mm, 48 mm, 49 mm, 50 mm or any value between two adjacent values.

[0144] In some embodiments, on the same projection plane perpendicular to the first direction z, the minimum distance between the projection of the liquid injection hole 12 and the projection of the weak portion 14 can be measured and obtained by projection method, laser ranging method, or software mapping method.

[0145] In the above solution, by setting the minimum distance between the projections of the injection hole 12 and the weak portion 14 on the same projection plane perpendicular to the first direction z to be greater than or equal to 5 mm, the effect of the pressure generated during electrolyte injection on the weak portion 14 can be effectively reduced, thereby reducing the risk of the battery cell 10 being scrapped due to rupture of the weak portion 14. By setting the minimum distance between the projections of the injection hole 12 and the weak portion 14 on the same projection plane perpendicular to the first direction z to be less than or equal to 50 mm, the interference of the injection hole 12 or the weak portion 14 on other structural components can be reduced, thereby making the battery device 100 compact when the battery device 100 is layered, thereby facilitating an increase in the volumetric energy density of the battery device 100. In this regard, by setting the minimum distance between the projections of the injection hole 12 and the weak portion 14 on the same projection plane perpendicular to the first direction z to be greater than or equal to 5 mm and less than or equal to 50 mm, the manufacturing yield and manufacturing efficiency of the battery cell 10 and the volumetric energy density of the battery device 100 can be balanced.

[0146] According to some embodiments of the present application, on the same projection plane perpendicular to the first direction z, the minimum distance between the projection of the liquid injection hole 12 and the projection of the weak portion 14 is greater than or equal to 10 mm and less than or equal to 20 mm.

[0147] On the same projection plane perpendicular to the first direction z, the projection of the injection hole 12 and the projection of the weak portion 14 are spaced apart from each other, and there is a distance between them, and the minimum distance between them is greater than or equal to 5 mm. Figure 6 For example, on the same projection plane SS perpendicular to the first direction z, the minimum distance w between the projected outer periphery of the liquid injection hole 12 and the projected inner periphery of the weak portion 14 can be 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm or any value between two adjacent values.

[0148] In the above solution, by setting the minimum distance between the projections of the injection hole 12 and the weak portion 14 on the same projection plane perpendicular to the first direction z to be greater than or equal to 10 mm, the impact of the pressure generated during electrolyte injection on the weak portion 14 can be further reduced, thereby reducing the risk of the battery cell 10 being scrapped due to rupture of the weak portion 14. By setting the minimum distance between the projections of the injection hole 12 and the weak portion 14 on the same projection plane perpendicular to the first direction z to be less than or equal to 20 mm, the interference of the injection hole 12 or the weak portion 14 on other structural components can be effectively reduced, thereby making the battery device 100 compact when the battery device 100 is assembled, thereby facilitating an increase in the volumetric energy density of the battery device 100. In this regard, by setting the minimum distance between the projections of the injection hole 12 and the weak portion 14 on the same projection plane perpendicular to the first direction z to be greater than or equal to 10 mm and less than or equal to 20 mm, the manufacturing yield and manufacturing efficiency of the battery cell 10 and the volumetric energy density of the battery device 100 can be effectively balanced.

[0149] According to some embodiments of this application, see Figure 3 The battery cell 10 further includes a first electrode terminal 16 and a second electrode terminal 17. The polarities of the first electrode terminal 16 and the second electrode terminal 17 are opposite. The first electrode terminal 16 and the second electrode terminal 17 are respectively arranged on the first wall 110, and the first electrode terminal 16 and the second electrode terminal 17 are arranged at intervals along the second direction y. The first direction z and the second direction y are perpendicular to each other.

[0150] In some embodiments, the battery cell 10 includes a first electrode terminal 16 and a second electrode terminal 17 of opposite polarity. For example, the first electrode terminal 16 is a positive electrode terminal connected to the positive electrode tab via an adapter, and the second electrode terminal 17 is a negative electrode terminal connected to the negative electrode tab via an adapter.

[0151] In some embodiments, the first electrode terminal 16 and the second electrode terminal 17 are both disposed on the first wall 110, and the first electrode terminal 16 and the second electrode terminal 17 are spaced apart along the second direction y. Alternatively, the first electrode terminal 16 is insulated and mounted on one end of the first wall 110 along the second direction y via an insulating structure, and the second electrode terminal 17 is insulated and mounted on the other end of the first wall 110 along the second direction y via an insulating structure.

[0152] The second direction y is perpendicular to the first direction z. Optionally, the housing 11 is square, the first direction z is the height direction of the battery cell 10, and the second direction y is the width direction of the battery cell 10, which is perpendicular to the thickness direction of the battery cell 10.

[0153] In the above scheme, on the one hand, the first electrode terminal 16 and the second electrode terminal 17 are both arranged on the first wall 110, so that the first electrode terminal 16 and the second electrode terminal 17 use the space on the same side, which is beneficial to the improvement of the space utilization rate of the battery cell 10, thereby facilitating the improvement of the volume energy density of the battery device 100; on the other hand, by arranging the first electrode terminal 16 and the second electrode terminal 17 and the weak portion 14 on two opposite walls, the impact of the rupture of the weak portion 14 to release the internal pressure of the battery cell 10 on the electrode terminals of the adjacent battery cells 10 can be reduced, thereby reducing the risk of internal short circuit in the battery device 100, thereby improving the reliability of the battery device 100.

[0154] According to some embodiments of this application, see Figure 3 , along the second direction y, the injection hole 12 is located between the first electrode terminal 16 and the second electrode terminal 17 .

[0155] In some embodiments, along the second direction y, the injection hole 12 is located between the first electrode terminal 16 and the second electrode terminal 17. Alternatively, along the second direction y, the injection hole 12 is centered between the first electrode terminal 16 and the second electrode terminal 17, that is, the distance between the injection hole 12 and the first electrode terminal 16 is equal to the distance between the injection hole 12 and the second electrode terminal 17. Alternatively, along the second direction y, the injection hole 12 is more biased toward one of the first electrode terminal 16 and the second electrode terminal 17, for example, the distance between the injection hole 12 and the first electrode terminal 16 is greater than the distance between the injection hole 12 and the second electrode terminal 17.

[0156] In the above scheme, the injection hole 12 is arranged between the first electrode terminal 16 and the second electrode terminal 17, so that the distance between the injection hole 12 and the first electrode terminal 16 and the distance between the injection hole 12 and the second electrode terminal 17 are appropriate, thereby reducing the risk of electrolyte adhering to the first electrode terminal 16 or the second electrode terminal 17 during the electrolyte injection process due to the distance between the injection hole 12 and the first electrode terminal 16 being too close or the distance between the injection hole 12 and the second electrode terminal 17 being too close, causing the production personnel to mistakenly judge that the battery cell 10 is leaking and affecting the production rhythm, thereby improving the production rhythm of the battery cell 10, and further contributing to the improvement of the manufacturing efficiency of the battery device 100.

[0157] In some other embodiments of the present application, along the second direction y, the liquid injection hole 12 may also be located on the side of the first electrode terminal 16 away from the second electrode terminal 17, or may also be located on the side of the second electrode terminal 17 away from the first electrode terminal 16. In some other embodiments of the present application, along the second direction y, a portion of the liquid injection hole 12 is located between the first electrode terminal 16 and the second electrode terminal 17, and another portion of the liquid injection hole 12 is located on the side of one of the first electrode terminal 16 and the second electrode terminal 17 away from the other.

[0158] According to some embodiments of the present application, along the second direction y, the distance between the liquid injection hole 12 and the first electrode terminal 16 is equal to the distance between the liquid injection hole 12 and the second electrode terminal 17 .

[0159] In some embodiments, see Figure 3 Along the second direction y, the distance between the injection hole 12 and the first electrode terminal 16 is equal to the distance between the injection hole 12 and the second electrode terminal 17, that is, the distance between the injection hole 12 and the first electrode terminal 16 and the distance between the injection hole 12 and the second electrode terminal 17 are both large. During the assembly of the battery cell 10, the risk of splashing the electrolyte to the first electrode terminal 16 and the second electrode terminal 17 during the injection process is relatively small.

[0160] In the above scheme, along the second direction y, by centeredly arranging the injection hole 12 between the first electrode terminal 16 and the second electrode terminal 17, the distance between the injection hole 12 and the first electrode terminal 16, and the distance between the injection hole 12 and the second electrode terminal 17 are appropriate, thereby reducing the risk of the electrolyte adhering to the electrode terminals during the injection process and affecting the production cycle.

[0161] According to some embodiments of the present application, along the second direction y, the distance between the liquid injection hole 12 and the first electrode terminal 16 is greater than the distance between the liquid injection hole 12 and the second electrode terminal 17 .

[0162] In some embodiments, see Figure 7 , Figure 7 This is a top view of a battery cell 10 in some embodiments of the present application. Along the second direction y, the distance between the injection hole 12 and the first electrode terminal 16 is greater than the distance between the injection hole 12 and the second electrode terminal 17. That is, the injection hole 12 is eccentric between the first electrode terminal 16 and the second electrode terminal 17. The larger distance between the injection hole 12 and the first electrode terminal 16 reduces the risk of electrolyte splashing onto the first electrode terminal 16 during assembly of the battery cell 10.

[0163] In the above scheme, along the second direction y, by setting the injection hole 12 farther away from the first electrode terminal 16, the risk of electrolyte adhering to the first electrode terminal 16 can be effectively reduced. At the same time, under the condition that the injection hole 12 and the weak portion 14 are staggered, the weak portion 14 can be centered between the first electrode terminal 16 and the second electrode terminal 17, thereby facilitating the rupture of the weak portion 14 under the internal pressure of the battery cell 10 and timely release of the internal pressure of the battery cell 10, thereby facilitating the improvement of the reliability of the battery cell 10, and further facilitating the improvement of the reliability of the battery device 100.

[0164] According to some embodiments of this application, see Figure 7 and Figure 8 , Figure 8 1 is a top view of a battery cell 10 in some other embodiments of the present application.

[0165] The first wall 110 has a first edge 1100 and a second edge 1101 in the third direction x. Along the third direction x, the distance between the liquid injection hole 12 and the first edge 1100 is equal to the distance between the liquid injection hole 12 and the second edge 1101. The first direction z, the second direction y and the third direction x are perpendicular to each other.

[0166] The third direction x, the second direction y and the first direction z are perpendicular to each other. Optionally, the housing 11 is square, the first direction z is the height direction of the battery cell 10, the second direction y may be the width direction of the battery cell 10, and the third direction x is the thickness direction of the battery cell 10.

[0167] In some embodiments, see Figure 8 Along the third direction x, the distance between the injection hole 12 and the first edge 1100 is equal to the distance between the injection hole 12 and the second edge 1101, that is, along the third direction x, the injection hole 12 is centered between the first edge 1100 and the second edge 1101.

[0168] In the above scheme, along the third direction x, the injection hole 12 is centered between the first edge 1100 and the second edge 1101, so that the distance between the injection hole 12 and the first edge 1100 and the distance between the injection hole 12 and the second edge 1101 are appropriate, thereby reducing the risk of the electrolyte adhering to the two opposite walls of the battery cell 10 along the third direction x during the injection process and affecting the production rhythm.

[0169] According to some embodiments of the present application, the first wall 110 has a first edge 1100 and a second edge 1101 in the third direction x. Along the third direction x, the distance between the injection hole 12 and the first edge 1100 is greater than the distance between the injection hole 12 and the second edge 1101, and the first direction z, the second direction y and the third direction x are perpendicular to each other.

[0170] The third direction x, the second direction y and the first direction z are perpendicular to each other. Optionally, the housing 11 is square, the first direction z is the height direction of the battery cell 10, the second direction y can be the width direction of the battery cell 10, and the third direction x is the thickness direction of the battery cell 10. In some embodiments, see Figure 7 Along the third direction x, the distance between the liquid injection hole 12 and the first edge 1100 is greater than the distance between the liquid injection hole 12 and the second edge 1101, that is, in the third direction x, the liquid injection hole 12 is eccentric between the first edge 1100 and the second edge 1101, and the distance between the liquid injection hole 12 and the first edge 1100 is larger.

[0171] In the above scheme, along the third direction x, by setting the injection hole 12 farther away from the first edge 1100, and under the condition that the injection hole 12 and the weak portion 14 are staggered, the weak portion 14 can be centered on the second wall 112 along the third direction x, thereby facilitating the weak portion 14 to rupture under the internal pressure of the battery cell 10 and timely release the internal pressure of the battery cell 10, thereby facilitating the improvement of the reliability of the battery cell 10, and further facilitating the improvement of the reliability of the battery cell 10, and further facilitating the improvement of the reliability of the battery device 100.

[0172] According to some embodiments of the present application, along the second direction y, the distance between the injection hole 12 and the first electrode terminal 16 is greater than or equal to 40 mm, and the distance between the injection hole 12 and the second electrode terminal 17 is greater than or equal to 40 mm.

[0173] In some embodiments, along the second direction y, the minimum distance between the injection hole 12 and the first electrode terminal 16 may be greater than or equal to 40 mm, for example, see Figure 8 Along the second direction y, the distance L1 between the liquid injection hole 12 and the first electrode terminal 16 can be 40mm, 41mm, 42mm, 43mm, 44mm, 45mm, 46mm, 47mm, 48mm, 49mm, 50mm or a larger value or any value between two adjacent values.

[0174] In some embodiments, along the second direction y, the minimum distance between the injection hole 12 and the second electrode terminal 17 may be greater than or equal to 40 mm, for example, see Figure 8 Along the second direction y, the distance L2 between the injection hole 12 and the second electrode terminal 17 can be 40mm, 41mm, 42mm, 43mm, 44mm, 45mm, 46mm, 47mm, 48mm, 49mm, 50mm or a larger value or any value between two adjacent values.

[0175] In some embodiments, along the second direction y, the distance between the injection hole 12 and the first electrode terminal 16 , and the distance between the injection hole 12 and the second electrode terminal 17 can be measured and obtained by projection, laser ranging, or software mapping.

[0176] In some embodiments, along the second direction y, the distance L1 between the liquid injection hole 12 and the first electrode terminal 16 and the distance L2 between the liquid injection hole 12 and the second electrode terminal 17 may be equal to or different from each other. For example, along the second direction y, the distance L1 between the liquid injection hole 12 and the first electrode terminal 16 is 40 mm, and the distance L2 between the liquid injection hole 12 and the second electrode terminal 17 is 40 mm, or along the second direction y, the distance L1 between the liquid injection hole 12 and the first electrode terminal 16 is 45 mm, and the distance L2 between the liquid injection hole 12 and the second electrode terminal 17 is 40 mm.

[0177] In the above scheme, along the second direction y, by setting the distance between the injection hole 12 and the first electrode terminal 16 to be greater than or equal to 40 mm, the risk of the electrolyte adhering to the first electrode terminal 16 and affecting the production cycle during injection can be effectively reduced; along the second direction y, by setting the distance between the injection hole 12 and the second electrode terminal 17 to be greater than or equal to 40 mm, the risk of the electrolyte adhering to the second electrode terminal 17 and affecting the production cycle during injection can be effectively reduced.

[0178] According to some embodiments of this application, see Figure 9 , Figure 9 for Figure 5 The enlarged view of point B in the figure. It should be noted that Figure 5 The sealing member 12a for sealing the liquid injection hole 12 is hidden in the figure. The liquid injection hole 12 includes a first hole segment 120 and a second hole segment 121. The first hole segment 120 and the second hole segment 121 are arranged in a direction from the first wall 110 to the second wall 112. The aperture of the first hole segment 120 is larger than that of the second hole segment 121.

[0179] In some embodiments, the injection hole 12 is in the shape of a stepped hole, which may include a first hole segment 120 and a second hole segment 121 arranged along the first direction z. Relative to the second hole segment 121, the first hole segment 120 is located on the outside of the first wall 110, that is, the second hole segment 121 is closer to the inside of the shell 11.

[0180] In some embodiments, the diameter of the first hole segment 120 is greater than the diameter of the second hole segment 121, that is, the size of the first hole segment 120 is greater than the size of the second hole segment 121, that is, on the same projection plane perpendicular to the first direction z, the area enclosed by the projection of the first hole segment 120 is greater than the area enclosed by the second hole segment 121.

[0181] In some embodiments, the first hole segment 120 and the second hole segment 121 may transition through a straight surface; in other embodiments, the first hole segment 120 and the second hole segment 121 may transition through an inclined surface or a curved surface.

[0182] In some embodiments, the injection hole 12 is a multi-segment through-hole structure, which may include a first hole segment 120 , a second hole segment 121 , a third hole segment or more hole segments.

[0183] In the above scheme, by setting the injection hole 12 as a stepped hole shape and setting the aperture of the first hole section 120 located on the outside to be larger than the aperture of the second hole section 121 located on the inside, it is convenient for the injection equipment to inject liquid into the interior of the shell 11 through the injection hole 12, providing a larger space for the injection of electrolyte, thereby reducing the risk of electrolyte splashing outward, which is beneficial to improving the production rhythm of the battery cell 10, and further beneficial to improving the manufacturing efficiency of the battery device 100.

[0184] In some embodiments of the present application, the liquid injection hole 12 may be a hole segment structure, and the hole wall of the liquid injection hole 12 extends straight along the first direction z and connects the outer side and the inner side of the first wall 110 .

[0185] According to some embodiments of the present application, the diameter of the first hole section 120 is greater than or equal to 4 mm and less than or equal to 10 mm.

[0186] In some embodiments, the hole wall of the first hole segment 120 is a straight wall portion extending along the first direction z, and the diameter of the first hole segment 120 may be greater than or equal to 4 mm and less than or equal to 10 mm.

[0187] In some embodiments, the hole wall of the first hole section 120 is an inclined wall portion, for example, the hole wall of the first hole section 120 is inclined inward along the direction of the first wall 110 pointing to the second wall 112, and the maximum hole diameter of the first hole section 120 can be greater than or equal to 4 mm and less than or equal to 10 mm.

[0188] For example, see Figure 9 The aperture of the first hole section 120 is R1, and the value of R1 can be 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm or any value between two adjacent values.

[0189] In the above scheme, by setting the aperture of the first hole segment 120 to be greater than or equal to 4 mm, a larger space can be effectively provided for the electrolyte, reducing the risk of electrolyte splashing outward, which is beneficial to improving the production cycle of the battery cell 10; by setting the first hole segment 120 to be less than or equal to 10 mm, the space occupied by the injection hole 12 on the first wall 110 can be reduced, thereby facilitating the layout of other structural parts, making the battery device 100 compact, and improving the volume energy density of the battery device 100.

[0190] According to some embodiments of the present application, the center of the weak portion 14 coincides with the center of the second wall 112 .

[0191] In some embodiments, the center of the weak portion 14 may be the geometric center of the weak portion 14. For example, the weak portion 14 is annular, and its center may be located in the inner ring and at the center of the inner ring. Figure 10 As shown, the weak portion 14 includes three sections, including a first slot section 141 , a second slot section 142 and a third slot section 143 . The second slot section 142 includes the first slot section 141 and the third slot section 143 . The center of the weak portion 14 can be the center of the second slot section 142 .

[0192] The center of the second wall 112 may be the geometric center of the second wall 112 , and along the first direction z, the central axis of the housing 11 may pass through the center of the second wall 112 .

[0193] “The center of the weak portion 14 coincides with the center of the second wall 112 ” may be understood as, along the first direction z, the central axis of the housing 11 may pass through the center of the second wall 112 and the center of the weak portion 14 .

[0194] In the above solution, by setting the center of the weak portion 14 to coincide with the center of the second wall 112, the internal pressure of the battery cell 10 can be effectively applied to the weak portion 14, so that the weak portion 14 ruptures more promptly to release the internal pressure of the battery cell 10, thereby reducing the risk of explosion of the battery cell 10, and improving the reliability of the battery cell 10 and the reliability of the battery device 100.

[0195] According to some embodiments of the present application, on the same projection plane perpendicular to the first direction z, the projection of the liquid injection hole 12 and the projection of the pressure relief area 15 do not overlap with each other.

[0196] In some embodiments, the location where the weak portion 14 is located defines a pressure relief zone 15. For example, the weak portion 14 is a non-closed notch structure. Optionally, the weak portion 14 includes one or more notches spaced apart from each other. When the internal pressure of the battery cell 10 increases to a certain level, each notch ruptures to release the pressure. In these embodiments, the location where the weak portion 14 itself is located defines the pressure relief zone 15.

[0197] In the above scheme, in some embodiments, the location where the weak portion 14 is located can form a pressure relief zone 15. By setting the projections of the injection hole 12 and the pressure relief zone 15 on the same projection plane perpendicular to the first direction z to be non-overlapping, the pressure generated when the electrolyte is injected into the interior of the shell through the injection hole 12 can be effectively reduced. The impact on the pressure relief zone causes the pressure relief zone 15, that is, the weak portion 14, to be damaged and ruptured, resulting in the risk of the battery cell being scrapped, so that the battery cell has a higher yield rate during the manufacturing process, which is beneficial to the improvement of the manufacturing efficiency of the battery cell, and then to the improvement of the manufacturing efficiency of the battery device.

[0198] According to some embodiments of the present application, the second wall 112 is provided with a notched groove 140 , the bottom wall of the notched groove 140 is a weak portion 14 , and the notched groove 140 defines a pressure relief area 15 .

[0199] In some embodiments, the weak portion 14 is formed on the second wall 112 and has a structural strength that is weaker than other portions of the second wall 112. For example, a notched groove 140 is provided on the second wall 112 so that the thickness of the bottom wall of the notched groove 140 is thicker than the thickness of other portions of the second wall 112, thereby forming a weak portion 14 with weaker structural strength.

[0200] In some embodiments, the score groove 140 can be directly or indirectly provided on the second wall 112. Alternatively, the score groove 140 can be directly provided on the second wall 112 by processes such as die casting, stamping, and turning. Alternatively, the score groove 140 can be first formed on other structural components, which are then integrated into the second wall 112. For example, the second wall 112 includes a wall body 1120 and a pressure relief member 1121. The wall body 1120 is formed with a first through hole 1122. The pressure relief member 1121 is integrally formed with the score groove 140. The pressure relief member 1121 is connected to the wall body 1120 and closes the first through hole 1122. Alternatively, the score groove 140 can be formed on the pressure relief member 1121 by processes such as die casting, turning, and stamping.

[0201] In some embodiments, the scored groove 140 comprises a multi-segment groove structure, which can be interconnected or independent of each other. Optionally, the scored groove 140 comprises a multi-segment groove structure, which is interconnected to define a larger pressure relief area 15. Optionally, the scored groove 140 comprises a multi-segment groove structure, which is independent of each other to define multiple pressure relief areas 15.

[0202] In the above solution, by providing a notched groove 140 on the second wall 112 and forming the bottom wall of the notched groove 140 as a weakened portion 14, the second wall 112 can be ruptured along the notched groove 140 under the internal pressure of the battery cell 10 to open the pressure relief area 15 and release the internal pressure of the battery cell 10, thereby improving the reliability of the battery cell 10. Furthermore, the notched groove 140 is simple to manufacture, and using the notched groove 140 to form the weakened portion 14 helps improve the manufacturing efficiency of the battery cell 10.

[0203] According to some embodiments of this application, see Figure 10 , Figure 10 Schematic diagram of the second wall 112 and the weakened portion 14 in some embodiments of the present application. The scored groove 140 includes a first groove segment 141, a second groove segment 142, and a third groove segment 143. The first groove segment 141 and the third groove segment 143 are arranged opposite each other along the second direction y. The second groove segment 142 is located between and connects the first and third groove segments 141, 143. The first, second, and third groove segments 141, 142, 143 collectively define a pressure relief area 15. The first direction z and the second direction y are perpendicular to each other.

[0204] In some embodiments, the scoring groove 140 includes a three-section groove structure, including a first groove section 141, a second groove section 142, and a third groove section 143. The first groove section 141 is a straight groove extending along the third direction x, the third groove section 143 is a straight groove extending along the third direction x, and the second groove section 142 is a straight groove extending along the second direction y. The second groove section 142 is located between the first groove section 141 and the third groove section 143, with one end of the second groove section 142 connected to the middle of the first groove section 141 and the other end of the second groove section 142 connected to the middle of the third groove section 143. Optionally, see Figure 10 The first, second, and third sections 141, 142, 143 of the scored groove 140 form an H-shaped (or inverted H-shaped) groove structure, i.e., an H-shaped pressure relief area 15. For example, when the internal pressure of the battery cell 10 expands to a certain level, the internal pressure breaks through the bottom walls of the first, second, and third sections 141, 142, 143, forming an H-shaped pattern.

[0205] In the above solution, the scored groove 140 has a simple structure, comprising a first groove section 141, a third groove section 143, and a second groove section 142 connecting the first groove section 141 and the third groove section 143. When the internal pressure of the battery cell 10 expands to a certain extent, the second wall 112 can rupture along the first groove section 141, the second groove section 142, and the third groove section 143, thereby providing the battery cell 10 with a larger pressure relief area, facilitating the rapid release of internal pressure from the battery cell 10, thereby improving the reliability of the battery cell 10 and, in turn, the battery device 100.

[0206] According to some embodiments of this application, see Figure 10 On the same projection plane perpendicular to the first direction z, the projection of the liquid injection hole 12 is located between the projection of the first groove section 141 and the projection of the third groove section 143.

[0207] exist Figure 10 , the dotted line represents the projection of the injection hole 12 onto the second wall 112. Along the third direction x, the injection hole 12 can be located on one side of the second slot segment 142, and along the second direction y, the injection hole 12 can be located between the first slot segment 141 and the third slot segment 143.

[0208] In the above scheme, on the same projection plane perpendicular to the first direction z, by arranging the projection of the injection hole 12 between the projection of the first groove section 141 and the projection of the second groove section 142, on the one hand, it is possible to reduce the risk of the pressure generated during the electrolyte injection process directly acting on the groove bottom wall of the first groove section 141 and the groove bottom wall of the second groove section 142, thereby causing the second wall 112 to rupture during the manufacturing process of the battery cell 10; on the other hand, it is possible to improve the space utilization rate of the injection hole 12 and the weak portion 14, thereby providing a larger space for other structural components of the battery device 100, which is beneficial to the spatial layout of other structural components of the battery device 100, and thus beneficial to the volume energy density of the battery device 100.

[0209] In some other embodiments, along the second direction y, the injection hole 12 can be located on the side of the first slot section 141 away from the third slot section 143 , or along the second direction y, the injection hole 12 can be located on the side of the third slot section 143 away from the first slot section 141 .

[0210] According to some embodiments of this application, see Figure 11 The scoring groove 140 includes an annular scoring groove 140 a, and the annular scoring groove 140 a is surrounded to form a pressure relief area 15.

[0211] In some embodiments, the scored groove 140 is annular and can be formed by connecting one or more groove segments end to end to form an annular scored groove 140a. For example, the annular scored groove 140a can be circular, polygonal, flat, or other shapes. Alternatively, the annular scored groove 140a can be formed by connecting four straight groove segments end to end. Alternatively, the annular scored groove 140a can include two straight groove segments and two arcuate groove segments, with the two straight groove segments connected by two arcuate groove segments.

[0212] Optionally, when the internal pressure of the battery cell 10 expands to a certain extent, the internal pressure will expand the entire groove structure of the annular notch 140 a to form a larger pressure relief gap on the second wall 112 to release the internal pressure.

[0213] Optionally, when the internal pressure of the battery cell 10 expands to a certain extent, the internal pressure breaks through part of the groove structure of the annular notch groove 140a, so that a part of the pressure relief area 15 formed by the annular notch groove 140a flips outward, and the other part is connected to the second wall 112, thereby releasing the internal pressure of the battery cell 10.

[0214] In the above solution, the notched groove 140 is annular to enclose a relatively large pressure relief area 15 , thereby providing the battery cell 10 with a relatively large pressure relief area, thereby enabling the internal pressure of the battery cell 10 to be quickly released, and making the battery device 100 more reliable.

[0215] According to some embodiments of this application, see Figure 11 , Figure 11 Schematic diagram of the second wall 112 and the scoring groove 140 in some embodiments of the present application.

[0216] The annular scored groove 140a includes a first straight segment 144, a second straight segment 145, a first arc segment 146, and a second arc segment 147. The first straight segment 144 and the second straight segment 145 are disposed opposite each other along the third direction x. The first arc segment 146 and the second arc segment 147 are disposed opposite each other along the second direction y. One end of the first straight segment 144 and one end of the second straight segment 145 are connected by the first arc segment 146, and the other end of the first straight segment 144 and the other end of the second straight segment 145 are connected by the second arc segment 147. The thickness of the groove bottom wall of the second straight segment 145, the thickness of the groove bottom wall of the first arc segment 146, and the thickness of the groove bottom wall of the second arc segment 147 are all less than the thickness of the groove bottom wall of the first straight segment 144. The first direction z, the second direction y, and the third direction x are mutually perpendicular.

[0217] In some embodiments, the first straight segment 144 is a straight groove extending along the second direction y, and the second straight segment 145 is a straight groove extending along the second direction y. The first straight segment 144 and the second straight segment 145 are spaced apart from each other along the third direction x. The first arc segment 146 is arc-shaped and located on one side of the first and second straight segments 144, 145 along the second direction y. The second arc segment 147 is arc-shaped and located on the other side of the first and second straight segments 144, 145 along the second direction y. Along the second direction y, one end of the first straight segment 144 and one end of the second straight segment 145 are connected by the first arc segment 146, and the other end of the first straight segment 144 and the other end of the second straight segment 145 are connected by the second arc segment 147.

[0218] “The thickness of the groove bottom wall of the second straight segment 145, the thickness of the groove bottom wall of the first arc segment 146 and the thickness of the groove bottom wall of the second arc segment 147 are all less than the thickness of the groove bottom wall of the first straight segment 144” can be understood as, the structural strength of the groove bottom wall of the first straight segment 144 is greater than the structural strength of the groove bottom wall of the second straight segment 145, and the structural strength of the groove bottom wall of the first straight segment 144 is greater than the structural strength of the groove bottom wall of the first arc segment 146, and the structural strength of the groove bottom wall of the first straight segment 144 is greater than the structural strength of the groove bottom wall of the second arc segment 147; or it can be understood as, when the internal pressure of the battery cell 10 expands to a certain extent, the internal pressure will break through the groove bottom wall of the second straight segment 145, the groove bottom wall of the first arc segment and the groove bottom wall of the second arc segment 147, and the groove bottom wall of the first straight segment 144 may not be broken, or will only be broken when the internal pressure of the battery cell 10 further increases.

[0219] In the above scheme, by setting the thickness of the second wall 112 along the second straight segment 145, the first arc segment 146 and the second arc segment 147 to be smaller, when the internal pressure of the battery cell 10 expands to a certain extent, the second wall 112 can rupture along the second straight segment 145, the first arc segment 146 and the second arc segment 147 to quickly release the internal pressure of the battery cell 10, so that the battery device 100 has higher reliability; at the same time, because the thickness of the bottom wall of the groove of the first straight segment 144 is larger, the pressure relief area 15 can be retained in the second wall 112 at the position of the first straight segment 144, reducing the risk of the rectified weak portion 14 being subjected to pressure and impacting the adjacent battery cell 10 or other structural parts of the battery device 100, causing damage to the adjacent battery cell 10 or other structural parts of the battery device 100, thereby improving the reliability of the battery device 100.

[0220] According to some embodiments of this application, see Figure 11The scored groove 140 further includes a fourth groove segment 148 and a fifth groove segment 149, which are located within the pressure relief area 15 and are each arc-shaped. Along the third direction x, the fourth groove segment 148 and the fifth groove segment 149 are disposed opposite each other, and the outer edges of the fourth groove segment 148 and the outer edges of the fifth groove segment 149 are tangent to each other. The thickness of the groove bottom wall of the second straight segment 145, the thickness of the groove bottom wall of the first arc segment, and the thickness of the groove bottom wall of the second arc segment 147 are all less than or equal to the thickness of the groove bottom wall of the fourth groove segment 148. The thickness of the groove bottom wall of the second straight segment 145, the thickness of the groove bottom wall of the first arc segment, and the thickness of the groove bottom wall of the second arc segment 147 are all less than or equal to the thickness of the groove bottom wall of the fifth groove segment 149.

[0221] In some embodiments, groove structures may be provided within the pressure relief zone 15 defined by the annular notch groove 140a to facilitate opening of the pressure relief zone 15 and release of internal pressure. Optionally, a fourth groove segment 148 and a fifth groove segment 149 may be provided within the pressure relief zone 15. The fourth groove segment 148 may be arc-shaped, and the fifth groove segment 149 may be arc-shaped. Along the third direction x, the center of the fourth groove segment 148 is located on a side facing away from the fifth groove segment 149, and the center of the fifth groove segment 149 is located on a side facing away from the fourth groove segment 148. The outer edges of the fourth groove segment 148 and the outer edges of the fifth groove segment 149 are tangent.

[0222] “The thickness of the bottom wall of the second straight segment 145, the thickness of the bottom wall of the first arc segment, and the thickness of the bottom wall of the second arc segment 147 are all less than or equal to the thickness of the bottom wall of the fourth slot segment 148, and the thickness of the bottom wall of the second straight segment 145, the thickness of the bottom wall of the first arc segment, and the thickness of the bottom wall of the second arc segment 147 are all less than or equal to the thickness of the bottom wall of the fifth slot segment 149” can be understood as that the structural strength of the bottom wall of the fourth slot segment 148 and the fifth slot segment 149 is greater than the structural strength of the bottom wall of the second straight segment 145, and the fourth slot segment 148 and the fifth slot segment The structural strength of the groove bottom wall of 149 is greater than the structural strength of the groove bottom wall of the first arc segment, and the structural strength of the groove bottom wall of the fourth groove segment 148 and the fifth groove segment 149 is greater than the structural strength of the groove bottom wall of the second arc segment 147; or it can be understood that when the internal pressure of the battery cell 10 expands to a certain extent, the internal pressure will break through the groove bottom wall of the second straight segment 145, the groove bottom wall of the first arc segment and the groove bottom wall of the second arc segment 147, and the groove bottom walls of the fourth groove segment 148 and the fifth groove segment 149 may not be broken, or will only break through when the internal pressure of the battery cell 10 increases further.

[0223] In the above scheme, the scored groove 140 also includes a fourth groove section 148 and a fifth groove section 149, and the fourth groove section 148 and the fifth groove section 149 are located in the pressure relief area 15, which can reduce the structural strength of the portion of the second wall 112 located in the pressure relief area 15, so that when the weak portion 14 is subjected to the internal pressure of the battery cell 10, it can facilitate the rupture of the portion where the pressure relief area 15 is located, so as to quickly release the internal pressure of the battery cell 10, thereby effectively improving the reliability of the battery device 100.

[0224] According to some embodiments of the present application, a portion where the outer edge of the fourth slot segment 148 and the outer edge of the fifth slot segment 149 are tangent to each other coincides with the center of the second wall 112 .

[0225] In some embodiments, along the first direction z, the central axis of the housing 11 may pass through a portion where the center of the second wall 112 is tangent to the outer edges of the fourth slot segment 148 and the fifth slot segment 149 .

[0226] In the above scheme, by setting the tangent parts of the outer edge side of the fourth groove segment 148 and the outer edge side of the fifth groove segment 149 to coincide with the center of the second wall 112, the internal pressure of the battery cell 10 can be uniformly applied to the annular notch groove 140a through the fourth groove segment 148 and the fifth groove segment 149, thereby facilitating the rupture of the second wall 112 along the second straight line segment 145, the first arc segment and the second arc segment 147, so as to quickly release the internal pressure of the battery cell 10, so that the battery device 100 has higher reliability.

[0227] According to some embodiments of this application, see Figure 11 Along the second direction y, one end of the first straight segment 144 is connected to one end of the fourth slot segment 148, and the other end of the first straight segment 144 is connected to the other end of the fourth slot segment 148. Along the second direction y, one end of the second straight segment 145 is connected to one end of the fifth slot segment 149, and the other end of the second straight segment 145 is connected to the other end of the fifth slot segment 149.

[0228] In some embodiments, both ends of the fourth slot segment 148 extend to the first straight segment 144 , respectively, such that the fourth slot segment 148 and the first straight segment 144 are interconnected.

[0229] In some embodiments, both ends of the fifth slot segment 149 extend to the second straight segment 145 , respectively, so that the fifth slot segment 149 and the second straight segment 145 are connected to each other.

[0230] In the above solution, by extending the two ends of the fourth groove segment 148 to the first straight segment 144 and extending the two ends of the fifth groove segment 149 to the second straight segment 145, the internal pressure of the battery cell 10 can be effectively applied to the annular notched groove 140a, thereby facilitating the rupture of the annular notched groove 140a to release the internal pressure of the battery cell 10, thereby facilitating the improvement of the reliability of the battery device 100.

[0231] In some other embodiments of the present application, both ends of the fourth slot segment 148 may be spaced apart from the first straight segment 144 , and both ends of the fifth slot segment 149 may be spaced apart from the second straight segment 145 .

[0232] According to some embodiments of this application, see Figure 11 On the same projection plane perpendicular to the first direction z, the projection of the liquid injection hole 12 is located in the area enclosed by the projection of the first arc segment, the projection of the fourth groove segment 148 and the projection of the fifth groove segment 149.

[0233] exist Figure 11 In the figure, the dotted line represents the projection of the injection hole 12 onto the second wall 112. The projection of the injection hole 12 is located in the area enclosed by the projection of the first arc segment, the projection of the fourth groove segment 148 and the projection of the fifth groove segment 149.

[0234] In the above scheme, on the same projection plane perpendicular to the first direction z, by setting the projection of the injection hole 12 in the area surrounded by the projection of the first arc segment, the projection of the fourth groove segment 148 and the projection of the fifth groove segment 149, on the one hand, the pressure generated during the electrolyte injection process can be reduced from directly acting on the scored groove 140, thereby causing the risk of the second wall 112 rupturing during the manufacturing process of the battery cell 10; on the other hand, the space utilization rate of the injection hole 12 and the weak portion 14 can be improved, thereby providing a larger space for other structural components of the battery device 100, which is beneficial to the spatial layout of other structural components of the battery device 100, and thus beneficial to the volume energy density of the battery device 100.

[0235] Optionally, in some other embodiments, the projection of the liquid injection hole 12 may be located within the area enclosed by the projection of the second arc segment 147 , the projection of the fourth slot segment 148 , and the projection of the fifth slot segment 149 .

[0236] Alternatively, in some other embodiments, the projection of the liquid injection hole 12 may be located outside the annular scoring groove 140a.

[0237] According to some embodiments of the present application, the weak portion 14 is integrally formed on the second wall 112 .

[0238] In some embodiments, the weak portion 14 can be directly formed on the second wall 112 , for example, by forming a groove structure or a recessed structure on the second wall 112 through processes such as die-casting, stamping, or turning to form the weak portion 14 .

[0239] In the above solution, the weak portion 14 can be formed on the second wall 112 by an integral molding process, which can reduce the manufacturing steps of the battery cell 10 and effectively improve the manufacturing efficiency of the battery cell 10 , thereby facilitating the improvement of the manufacturing efficiency of the battery device 100 .

[0240] According to some embodiments of this application, see Figure 12 , Figure 12 Schematic diagram of a wall body 1120 and a pressure relief member 1121 in some embodiments of the present application. Second wall 112 includes wall body 1120 and pressure relief member 1121, with weakened portion 14 formed in pressure relief member 1121. Wall body 1120 has a first through hole 1122 extending therethrough in a first direction z. Pressure relief member 1121 is connected to wall body 1120 and closes first through hole 1122.

[0241] In some embodiments, the wall body 1120 is the main structure of the second wall 112, and can be used to enclose a closed space with the wall portion of the housing 11 to accommodate the electrode assembly 13. Along the first direction z, the wall body 1120 is formed with a first through hole 1122 therethrough.

[0242] In some embodiments, the pressure relief member 1121 is a structural member connected to the wall body 1120, which can close the first through hole 1122. Optionally, the pressure relief member 1121 can be a plate-like structure, which is connected to the wall body 1120 to close the first through hole 1122. The connection relationship between the pressure relief member 1121 and the wall body 1120 is various, including welding, bonding, injection molding or screw connection. In some embodiments, the material of the wall body 1120 and the material of the pressure relief member 1121 can be the same or different. Optionally, the material of the wall body 1120 can be metal, such as aluminum, steel or other metals. The material of the pressure relief member 1121 can be metal or non-metal, such as aluminum, steel or other metals, or other non-metals such as plastic.

[0243] “The weak portion 14 is formed in the pressure relief member 1121 ” can be understood as that the weak portion 14 is formed in the pressure relief member 1121 , and the weak portion 14 is formed on the second wall 112 through the combination of the pressure relief member 1121 and the wall body 1120 .

[0244] In some embodiments, the weak portion 14 can be formed on the pressure relief member 1121 by die casting, stamping, turning, etc.

[0245] In the above scheme, the second wall 112 includes a wall body 1120 and a pressure relief member 1121, and the weak portion 14 is formed on the pressure relief member 1121. Through the connection between the pressure relief member 1121 and the wall body 1120, the first through hole 1122 of the wall body 1120 can be reduced in closure and the weak portion 14 can be set on the second wall 112, so that the battery cell 10 has a pressure relief function, which is beneficial to improving the reliability of the battery cell 10.

[0246] According to some embodiments of the present application, the projected area of ​​the pressure relief member 1121 on the projection plane perpendicular to the first direction z is greater than or equal to 200 mm. 2 , and less than or equal to 2000mm 2 .

[0247] In the above solution, by setting the projection area of ​​the pressure relief member 1121 along the first direction z to be greater than or equal to 200mm 2 , which can make the battery cell 10 have a larger pressure relief area and pressure relief rate, thereby making the battery cell 10 have higher reliability; by setting the projection area of ​​the pressure relief member 1121 along the first direction z to be less than or equal to 2000mm 2 , which can reduce the interference of the pressure relief member 1121 with other structural components of the battery device 100 and provide a larger space for other structural components, so that the battery device 100 has a compact structure, which is beneficial to improving the volume energy density of the battery device 100.

[0248] According to some embodiments of the present application, a battery device 100 is provided. The battery device 100 includes any one of the battery cells 10 provided in the first aspect.

[0249] See Figure 2 The battery device 100 includes a battery cell 10 and a box body 20 , and the battery cell 10 is accommodated in the box body 20 .

[0250] Optionally, multiple battery cell assemblies are provided in the housing 20, each battery cell assembly comprising multiple stacked battery cells 10, which are connected in series via a busbar. In some embodiments, multiple battery cell assemblies may be connected in series via a busbar.

[0251] According to some embodiments of the present application, an electrical device is further provided, comprising the battery cell 10 provided above and / or the battery device 100 provided above. The battery cell 10 provided above and / or the battery device 100 provided above are used to provide electrical energy.

[0252] Optionally, the electrical device is a vehicle 1000 , and the battery cell 10 can serve as a driving power source and / or a control power source for the vehicle 1000 .

[0253] Some embodiments of the present application provide a battery cell 10, see Figure 3-Figure 12 The battery cell 10 includes a housing 11 and an electrode assembly 13. The electrode assembly 13 is disposed within the housing 11. Along a first direction z, the housing 11 includes a first wall 110 and a second wall 112 opposing each other. The first wall 110 has an injection hole 12 through which electrolyte can be injected into the interior of the housing 11. The injection hole 12 can be a stepped hole, and the hole diameter of the hole section of the injection hole 12 away from the interior of the housing 11 can be larger than the hole diameter of the hole section closer to the interior of the housing 11.

[0254] The second wall 112 is formed with a weak portion 14 and a pressure relief area 15. The second wall 112 is configured to rupture along the weak portion 14 to open the pressure relief area 15. On the same projection plane perpendicular to the first direction z, the projection of the liquid injection hole 12 and the projection of the weak portion 14 do not overlap. In other words, it can be understood that along the first direction z, the liquid injection hole 12 and the weak portion 14 do not directly face each other.

[0255] In some embodiments, the first wall 110 is provided with a first electrode terminal 16 and a second electrode terminal 17. The first electrode terminal 16 and the second electrode terminal 17 have opposite polarities. For example, the first electrode terminal 16 is a positive electrode terminal for electrically connecting to the positive tab of the electrode assembly 13, and the second electrode terminal 17 is a negative electrode terminal for electrically connecting to the negative tab of the electrode assembly 13. Along the second direction y, the first electrode terminal 16 and the second electrode terminal 17 are spaced apart, and the injection hole 12 is provided between the first electrode terminal 16 and the second electrode terminal 17.

[0256] In some embodiments, the weak portion 14 may be formed directly or indirectly on the second wall 112 .

[0257] Optionally, a notched groove 140 is integrally formed on the second wall 112 , the bottom wall of the notched groove 140 is a weak portion 14 , and the notched groove 140 defines a pressure relief area 15 .

[0258] Optionally, second wall 112 includes a wall body 1120 and a pressure relief member 1121. Pressure relief member 1121 is integrally formed with a notched groove 140. The bottom wall of notched groove 140 forms a weakened portion 14. Notched groove 140 defines a pressure relief area 15. Wall body 1120 has a first through hole 1122 extending therethrough in a first direction z. Pressure relief member 1121 is connected to wall body 1120 and closes first through hole 1122.

[0259] In some embodiments, see Figure 10The scored groove 140 includes a first groove section 141, a second groove section 142 and a third groove section 143. The first groove section 141 and the third groove section 143 are arranged opposite to each other along the second direction y. The second groove section 142 is located between the first groove section 141 and the third groove section 143 and connects the first groove section 141 and the third groove section 143. The first groove section 141, the second groove section 142 and the third groove section 143 jointly define a pressure relief area 15. The first direction z and the second direction y are perpendicular to each other. On the same projection plane perpendicular to the first direction z, the projection of the liquid injection hole 12 is located between the projection of the first groove section 141 and the projection of the third groove section 143.

[0260] In other embodiments, see Figure 11 The scored groove 140 includes an annular scored groove 140a, a fourth groove segment 148, and a fifth groove segment 149. The annular scored groove 140a encloses and forms the pressure relief zone 15. The annular scored groove 140a includes a first straight segment 144, a second straight segment 145, a first arc segment, and a second arc segment 147. Along the third direction x, the first straight segment 144 and the second straight segment 145 are arranged opposite each other. Along the second direction y, the first arc segment 147 and the second arc segment 147 are arranged opposite each other. One end of the first straight segment 144 and one end of the second straight segment 145 are connected by the first arc segment, and the other end of the first straight segment 144 and the other end of the second straight segment 145 are connected by the second arc segment 147. The fourth groove segment 148 and the fifth groove segment 149 are located within the pressure relief zone 15, and the fourth groove segment 148 and the fifth groove segment 149 are both arc-shaped. Along the third direction x, the fourth groove segment 148 and the fifth groove segment 149 are arranged opposite each other, and the outer edges of the fourth groove segment 148 and the outer edges of the fifth groove segment 149 are tangent. On the same projection plane perpendicular to the first direction z, the projection of the liquid injection hole 12 is located within the area enclosed by the projections of the first arc segment, the fourth groove segment 148, and the fifth groove segment 149. Optionally, the thickness of the groove bottom wall of the second straight segment 145, the thickness of the groove bottom wall of the first arc segment, and the thickness of the groove bottom wall of the second arc segment 147 are all less than the thickness of the groove bottom wall of the first straight segment 144. The thickness of the groove bottom wall of the second straight segment 145, the thickness of the groove bottom wall of the first arc segment and the thickness of the groove bottom wall of the second arc segment 147 are all less than or equal to the thickness of the groove bottom wall of the fourth groove segment 148, and the thickness of the groove bottom wall of the second straight segment 145, the thickness of the groove bottom wall of the first arc segment and the thickness of the groove bottom wall of the second arc segment 147 are all less than or equal to the thickness of the groove bottom wall of the fifth groove segment 149.

[0261] In some embodiments, on the same projection plane perpendicular to the first direction z, the minimum distance between the projection of the liquid injection hole 12 and the projection of the bottom wall of the scored groove 140 is greater than or equal to 5 mm and less than or equal to 50 mm. Alternatively, on the same projection plane perpendicular to the first direction z, the minimum distance between the projection of the liquid injection hole 12 and the projection of the bottom wall of the scored groove 140 is greater than or equal to 10 mm and less than or equal to 20 mm.

[0262] In a battery cell 10 of this structure, by setting the projections of the injection hole 12 and the weak portion 14 on the same projection plane perpendicular to the first direction z to be non-overlapping, the risk of the injection pressure directly impacting the weak portion 14, causing the weak portion 14 to be damaged and ruptured, and causing the battery cell 10 to be scrapped, can be effectively reduced. This allows the battery cell 10 to have a higher yield rate during the manufacturing process, thereby facilitating an improvement in the manufacturing efficiency of the battery cell 10, and further facilitating an improvement in the manufacturing efficiency of the battery device 100.

[0263] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Persons skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A battery cell, characterized in that: include: A housing having a first wall and a second wall opposite to each other along a first direction, wherein the first wall has a liquid injection hole for injecting electrolyte into the interior of the housing; An electrode assembly is arranged inside the shell; wherein the second wall is formed with a weak portion and a pressure relief area, and the second wall is configured to be able to split along the weak portion to open the pressure relief area, and on the same projection plane perpendicular to the first direction, the projection of the injection hole and the projection of the weak portion do not overlap with each other.

2. The battery cell according to claim 1, wherein: On the same projection plane perpendicular to the first direction, the minimum distance between the projection of the liquid injection hole and the projection of the weak portion is greater than or equal to 5 mm and less than or equal to 50 mm.

3. The battery cell according to claim 2, characterized in that: On the same projection plane perpendicular to the first direction, the minimum distance between the projection of the liquid injection hole and the projection of the weak portion is greater than or equal to 10 mm and less than or equal to 20 mm.

4. The battery cell according to claim 1, wherein: The battery cell also includes a first electrode terminal and a second electrode terminal, the polarities of the first electrode terminal and the second electrode terminal are opposite, the first electrode terminal and the second electrode terminal are respectively arranged on the first wall, and the first electrode terminal and the second electrode terminal are arranged at intervals along a second direction, and the first direction and the second direction are perpendicular to each other.

5. The battery cell according to claim 4, characterized in that Along the second direction, the injection hole is located between the first electrode terminal and the second electrode terminal.

6. The battery cell according to claim 5, characterized in that Along the second direction, a distance between the injection hole and the first electrode terminal is equal to a distance between the injection hole and the second electrode terminal.

7. The battery cell according to claim 5, characterized in that Along the second direction, a distance between the liquid injection hole and the first electrode terminal is greater than a distance between the liquid injection hole and the second electrode terminal.

8. The battery cell according to claim 5, characterized in that The first wall has a first edge and a second edge in the third direction. Along the third direction, the distance between the injection hole and the first edge is equal to the distance between the injection hole and the second edge. The first direction, the second direction and the third direction are perpendicular to each other.

9. The battery cell according to claim 5, characterized in that: The first wall has a first edge and a second edge in the third direction. Along the third direction, the distance between the injection hole and the first edge is greater than the distance between the injection hole and the second edge. The first direction, the second direction and the third direction are perpendicular to each other.

10. The battery cell according to claim 5, characterized in that Along the second direction, a distance between the liquid injection hole and the first electrode terminal is greater than or equal to 40 mm, and a distance between the liquid injection hole and the second electrode terminal is greater than or equal to 40 mm.

11. The battery cell according to claim 1, characterized in that The injection hole includes a first hole segment and a second hole segment. The first hole segment and the second hole segment are arranged in a direction from the first wall to the second wall. The aperture of the first hole segment is larger than that of the second hole segment.

12. The battery cell according to claim 11, characterized in that The diameter of the first hole segment is greater than or equal to 4 mm and less than or equal to 10 mm.

13. The battery cell according to claim 1, characterized in that The center of the weak portion coincides with the center of the second wall.

14. The battery cell according to claim 1, characterized in that On the same projection plane perpendicular to the first direction, the projection of the liquid injection hole and the projection of the pressure relief area do not overlap with each other.

15. The battery cell according to claim 1, characterized in that The second wall is provided with a notched groove, the bottom wall of the notched groove is the weak portion, and the notched groove defines the pressure relief area.

16. The battery cell according to claim 15, characterized in that The scored groove includes a first groove segment, a second groove segment and a third groove segment. The first groove segment and the third groove segment are arranged opposite to each other along the second direction. The second groove segment is located between the first groove segment and the third groove segment and connects the first groove segment and the third groove segment. The first groove segment, the second groove segment and the third groove segment jointly define the pressure relief area, and the first direction and the second direction are perpendicular to each other.

17. The battery cell according to claim 16, characterized in that On the same projection plane perpendicular to the first direction, the projection of the liquid injection hole is located between the projection of the first groove section and the projection of the third groove section.

18. The battery cell according to claim 15, characterized in that The scoring groove includes an annular scoring groove, and the annular scoring groove is surrounded to form the pressure relief area.

19. The battery cell according to claim 18, characterized in that The annular scoring groove includes a first straight segment, a second straight segment, a first arc segment, and a second arc segment. Along the third direction, the first straight segment and the second straight segment are arranged opposite to each other. Along the second direction, the first arc segment and the second arc segment are arranged opposite to each other. One end of the first straight segment and one end of the second straight segment are connected by the first arc segment, and the other end of the first straight segment and the other end of the second straight segment are connected by the second arc segment. The thickness of the bottom wall of the groove of the second straight line segment, the thickness of the bottom wall of the groove of the first arc segment, and the thickness of the bottom wall of the groove of the second arc segment are all smaller than the thickness of the bottom wall of the groove of the first straight line segment, and the first direction, the second direction, and the third direction are perpendicular to each other.

20. The battery cell according to claim 19, characterized in that The scored groove further includes a fourth groove segment and a fifth groove segment, the fourth groove segment and the fifth groove segment are located in the pressure relief area, and the fourth groove segment and the fifth groove segment are respectively in the shape of an arc; Along the third direction, the fourth slot segment and the fifth slot segment are arranged opposite to each other, and the outer edge side of the fourth slot segment is tangent to the outer edge side of the fifth slot segment, the thickness of the slot bottom wall of the second straight line segment, the thickness of the slot bottom wall of the first arc segment, and the thickness of the slot bottom wall of the second arc segment are all less than or equal to the thickness of the slot bottom wall of the fourth slot segment, and the thickness of the slot bottom wall of the second straight line segment, the thickness of the slot bottom wall of the first arc segment, and the thickness of the slot bottom wall of the second arc segment are all less than or equal to the thickness of the slot bottom wall of the fifth slot segment.

21. The battery cell according to claim 20, characterized in that A portion where the outer edge of the fourth slot segment and the outer edge of the fifth slot segment are tangent to each other coincides with the center of the second wall.

22. The battery cell according to claim 20, characterized in that Along the second direction, one end of the first straight segment is connected to one end of the fourth slot segment, and the other end of the first straight segment is connected to the other end of the fourth slot segment; Along the second direction, one end of the second straight line segment is connected to one end of the fifth slot segment, and the other end of the second straight line segment is connected to the other end of the fifth slot segment.

23. The battery cell according to claim 20, characterized in that On the same projection plane perpendicular to the first direction, the projection of the liquid injection hole is located in an area enclosed by the projection of the first arc segment, the projection of the fourth groove segment, and the projection of the fifth groove segment.

24. The battery cell according to any one of claims 1 to 23, characterized in that: The weak portion is integrally formed on the second wall.

25. The battery cell according to any one of claims 1 to 23, characterized in that: The second wall includes a wall body and a pressure relief member, and the weak portion is formed in the pressure relief member; The wall body has a first through hole extending along the first direction, and the pressure relief member is connected to the wall body and closes the first through hole.

26. The battery cell according to claim 25, characterized in that On the projection surface perpendicular to the first direction, the projection area of ​​the pressure relief member is greater than or equal to 200 mm 2 , and less than or equal to 2000mm 2 .

27. A battery device, characterized in that: A battery cell comprising the battery cell according to any one of claims 1 to 26.

28. An electrical device, characterized in that: Comprising the battery cell according to any one of claims 1 to 26, and / or the battery device according to claim 27.

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