Single battery, battery pack and electronic device

Abstract

The invention provides a single battery, a battery pack and an electronic device. The single battery comprises a shell, an electrode assembly, a pole, a first insulating part and a sealing part, the shell comprises an end wall, and the end wall comprises a mounting hole; the electrode assembly is accommodated in the shell; the pole is fixed on the end wall and is electrically connected with the electrode assembly; the pole comprises a pole body part, a first limiting part and a second limiting part; the cylinder part penetrates through the mounting hole, the first limiting part is located outside the shell, and the second limiting part is located inside the shell; the first insulating part comprises a first part arranged between the first limiting part and the end wall and a second part connected with the first part, and the second part extends into the mounting hole; the sealing piece is clamped between the end wall and the second limiting part; at least one accommodating cavity is defined by the second part, the sealing part and one or more of the following parts: the hole wall of the mounting hole or the outer peripheral surface of the cylinder part. According to the invention, the technical problem of poor sealing performance between the pole and the shell in the existing single battery can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a single cell, a battery pack and an electronic device. Background Art

[0002] During the manufacturing process of single-cell batteries, the sealing performance between the terminal and the shell plays a vital role in the service life and safety of the single-cell battery. As the performance of single-cell batteries continues to improve, the requirements for single-cell battery sealing performance are also becoming increasingly higher.

[0003] However, the terminal sealing structure of single cells currently on the market has poor sealing performance, which can easily lead to many safety problems, such as leakage, short circuit, etc., and thus cannot meet the sealing requirements of high-performance single cells. Summary of the Invention

[0004] The present invention provides a single cell, a battery pack and an electronic device to improve the technical problem of poor sealing performance between a pole and a shell in existing single cells.

[0005] The present invention provides a single cell battery, which includes: a shell, an electrode assembly, a pole, a first insulating member and a sealing member; the shell includes an end wall, the end wall includes a mounting hole; the electrode assembly is accommodated in the shell; the pole is fixed to the end wall and electrically connected to the electrode assembly, the pole includes a column portion, a first limiting portion and a second limiting portion; the column portion passes through the mounting hole, the first limiting portion is located outside the shell, and extends from the column portion to the outer peripheral edge of the end wall, the second limiting portion is located inside the shell, and extends from the column portion to the outer peripheral edge of the end wall; the first insulating member includes a first part arranged between the first limiting portion and the end wall, a second part connected to the first part, and the second part extends into the mounting hole; the sealing member is clamped between the end wall and the second limiting portion, and the inner edge of the sealing member abuts against the outer peripheral surface of the column portion; wherein the second part and the sealing member, together with one or more of the following, form at least one accommodating cavity: the hole wall of the mounting hole, or the outer peripheral surface of the column portion.

[0006] In one embodiment of the present invention, at least one accommodating cavity includes a first accommodating cavity formed by the second part, the seal and the outer peripheral surface of the column part, and / or a second accommodating cavity formed by the second part, the seal and the hole wall of the mounting hole.

[0007] In one embodiment of the present invention, the second portion is in contact with the wall of the mounting hole, and a first accommodating cavity is formed between the second portion, the sealing member, and the outer peripheral surface of the column portion.

[0008] In one embodiment of the present invention, at least one accommodating cavity includes a first accommodating cavity formed by the second part, the seal and the outer peripheral surface of the column part, and a second accommodating cavity formed by the second part, the seal and the hole wall of the mounting hole, and the first accommodating cavity and the second accommodating cavity are connected through the gap between the second part and the seal.

[0009] In one embodiment of the present invention, a side of the sealing member facing away from the second limiting portion at least partially extends into the accommodating cavity.

[0010] In one embodiment of the present invention, at least one accommodating cavity includes a first accommodating cavity formed by the second part, the seal and the outer peripheral surface of the column part, and a second accommodating cavity formed by the second part, the seal and the hole wall of the mounting hole. The width dimension of the first accommodating cavity is W1, the width dimension of the second accommodating cavity is W2, and W1>W2.

[0011] In one embodiment of the present invention, 0.2 mm ≤ W1 ≤ 0.5 mm; and / or 0 ≤ W2 ≤ 0.15 mm.

[0012] In one embodiment of the present invention, the second limiting portion includes an abutting plane on the side facing the end wall, the abutting plane is transitionally connected to the outer peripheral surface of the cylindrical portion through an arc surface, and the inner edge of the seal at least partially abuts against the arc surface.

[0013] In one embodiment of the present invention, a chamfer is provided at an edge of the mounting hole facing the electrode assembly.

[0014] In one embodiment of the present invention, the projections of the first limiting portion, the first insulating member and the end wall along a predetermined direction have an overlapping area, the minimum width of the overlapping area is L1, and 0.3mm≤L1≤1.5mm, and the predetermined direction is the thickness direction of the end wall.

[0015] In one embodiment of the present invention, the single cell further includes a second insulating member, which is disposed on the side of the end wall facing the electrode assembly and at least partially extends between the second limiting portion and the end wall, and forms an annular overlapping surface with the second limiting portion; the minimum width of the annular overlapping surface is L2, and L2 ≥ 2.5 mm.

[0016] In one embodiment of the present invention, the side of the end wall facing away from the electrode assembly includes a recess, the recess is recessed toward the side of the electrode assembly, the mounting hole passes through the bottom wall of the recess, and the first insulating member is at least partially accommodated in the recess; on the side of the end wall facing the electrode assembly, the bottom wall of the recess protrudes toward the side of the electrode assembly to form a convex portion, and the convex portion abuts against the sealing member.

[0017] In one embodiment of the present invention, the depth of the recess along the thickness direction of the end wall is h1, and 0.05 mm ≤ h1 ≤ 1 mm.

[0018] In one embodiment of the present invention, the protrusion includes a top wall, the top wall abuts against the sealing member; along the thickness direction of the end wall, the outer contour projection of the top wall is located outside the outer contour projection of the sealing member.

[0019] In one embodiment of the present invention, the thickness of the end wall is h2, and on the side of the end wall facing the electrode assembly, the height of the protrusion protruding from the end wall is h3, and h3 ≥ (1 / 3) × h2.

[0020] In one embodiment of the present invention, the second limiting portion and the first limiting portion are both rotating body structures, and along the thickness direction of the end wall, the outer contour projection of the first limiting portion is located within the outer contour projection of the second limiting portion.

[0021] In one embodiment of the present invention, the first limiting portion is a riveted flange, and the side of the pole facing away from the electrode assembly also includes a groove, and the first limiting portion is arranged around the outer periphery of the groove; the groove includes a groove side wall, and the first limiting portion includes a bent portion and an extension portion, the bent portion connects the extension portion and the groove side wall, and the extension portion extends from the bent portion toward the outer peripheral edge of the end wall; wherein, the thickness of the extension portion is less than the thickness of the bent portion.

[0022] In one embodiment of the present invention, the end wall is clamped between the first limiting portion and the second limiting portion. Along the thickness direction of the end wall, the thickness of the second limiting portion is H, the outer contour radius of the second limiting portion is R1, and 12mm≤R1≤17mm, 12≤R1 / H≤16.875.

[0023] The present invention further provides a battery pack, which includes the single battery in any of the above embodiments.

[0024] The present invention further provides an electronic device, which includes the battery pack in the above embodiment.

[0025] Beneficial effects of the present invention: In the single cell battery of the present invention, at least one accommodating cavity is enclosed between the second portion of the first insulating member, the sealing member and the hole wall of the mounting hole, and one or more of the outer peripheral surface of the column portion. During the assembly and extrusion process of the sealing member and the end wall, the pole and the first insulating member, this structural design allows the gas on the sealing contact surface of the seal to enter the accommodating cavity without being retained at the sealing contact surface. Therefore, by utilizing the accommodating cavity to store the gas discharged during the assembly and extrusion process, the residual gas on the sealing contact surface can be effectively reduced, thereby improving the sealing reliability of the seal, thereby improving the technical problem of poor sealing performance between the pole and the shell in the single cell battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying any creative work.

[0027] In the attached figure:

[0028] Figure 1 A cross-sectional view of the overall structure of an example of a single cell of the present invention;

[0029] Figure 2 for Figure 1 A partial enlarged view of area A in the middle;

[0030] Figure 3 This is a schematic diagram of the electrode assembly structure of an example of a single cell of the present invention;

[0031] Figure 4 This is a schematic structural diagram of a single cell battery in an example of the present invention, in which the accommodating cavity includes a second accommodating cavity;

[0032] Figure 5 2. A schematic structural diagram of a single cell battery according to an embodiment of the present invention, wherein the accommodating cavity includes a first accommodating cavity;

[0033] Figure 6 A schematic structural diagram of a single cell battery in an example of the present invention, wherein the accommodating cavity includes a first accommodating cavity and a second accommodating cavity;

[0034] Figure 7 This is a schematic structural diagram of a single cell battery example according to the present invention, in which the first accommodation cavity and the second accommodation cavity are connected via a gap;

[0035] Figure 8 This is a schematic structural diagram of an example of a single cell battery according to the present invention, in which the sealing member extends into the accommodation cavity;

[0036] Figure 9 A partial enlarged view of the connection position of the end wall, the first insulating member and the terminal in an example of a single cell of the present invention;

[0037] Figure 10 This is a schematic diagram of a partial structure of a single cell according to an example of the present invention, in which a recess is provided on the end wall and a first insulating member is accommodated in the recess;

[0038] Figure 11 This is a schematic structural diagram of a single cell battery in an example of the present invention in which a recess is provided on the end wall;

[0039] Figure 12 A schematic diagram of the local structure of a concave portion in an example of a single cell of the present invention;

[0040] Figure 13 This is a schematic diagram of the overall structure of the electrode in an example of a single cell of the present invention;

[0041] Figure 14 An axial cross-sectional view of a terminal in an example of a single cell of the present invention;

[0042] Figure 15 A partial schematic diagram of the installation positions of the first limiting portion and the first insulating member in an example of a single battery of the present invention;

[0043] Figure 16 A partial schematic diagram of the installation position of the riveted flange in an example of a single cell of the present invention;

[0044] Figure 17 A partial schematic diagram of the mounting structure of the terminal on the end wall in an example of a single cell of the present invention;

[0045] Figure 18 is a schematic diagram of an example of a battery pack of the present invention;

[0046] Figure 19 FIG. 1 is a schematic diagram of an example of an electronic device according to the present invention.

[0047] The reference numerals are as follows:

[0048] 100, single cell; 110, housing; 111, end wall; 1111, mounting hole; 1112, chamfer; 1113, recess; 1114, protrusion; 1115, top wall; 1116, body; 112, side wall; 113, opening; 114, end cap; 120, electrode assembly; 121, positive electrode sheet; 1211, positive electrode current collector; 1212, first coating area; 1213, first uncoated area; 122, diaphragm; 123, negative electrode sheet; 1231, negative electrode current collector; 1232, second coating area; 1233, second uncoated area; 124, negative electrode tab; 125, positive electrode tab; 130, pole; 131, column; 132, first stopper; 1 321. Extension portion; 1322. Bending portion; 1323. Plane section; 1324. Curved section; 133. Second limiting portion; 1331. Abutting plane; 134. Arc surface; 135. Groove; 1351. Groove sidewall; 140. First insulating member; 141. Second portion; 142. First portion; 150. Sealing member; 151. Protruding structure; 160. Accommodating cavity; 161. First accommodating cavity; 162. Second accommodating cavity; 163. Gap; 170. Second insulating member; 171. Annular overlapping surface; 180. Current collecting member; 200. Battery pack; 210. Box; 211. First box portion; 212. Second box portion; 300. Electronic device; 310. Working portion. DETAILED DESCRIPTION

[0049] The following describes the embodiments of the present invention through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. The present invention may also be implemented or applied through various other specific embodiments. The details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present invention. The following embodiments and features therein may be combined with one another without conflict.

[0050] It should be noted that the illustrations provided in the following embodiments are merely schematic illustrations of the basic concept of the present invention. The drawings only show components related to the present invention and are not drawn according to the number, shape, and size of components in actual implementation. In actual implementation, the type, quantity, and proportion of each component may be changed arbitrarily, and the component layout may also be more complex.

[0051] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it will be apparent to those skilled in the art that the embodiments of the present invention may be practiced without these specific details. In other embodiments, well-known structures and devices are shown in block diagram form rather than in detail to avoid obscuring the embodiments of the present invention.

[0052] See also Figures 1 to 19 The present invention provides a single cell 100, a battery pack 200 and an electronic device 300. The single cell 100 forms at least one accommodating cavity 160 between the second portion 141 of the first insulating member 140, the sealing member 150 and the hole wall of the mounting hole 1111, and the outer peripheral surface of the column portion 131. This can effectively reduce the residual gas on the sealing contact surface of the sealing member 150 during the assembly and extrusion process, thereby improving the sealing reliability of the sealing member 150 and reducing the risk of sealing failure between the pole 130 and the shell 110.

[0053] See also Figure 1 and Figure 2 In an embodiment of a single cell 100 of the present invention, the single cell 100 includes a housing 110 , an electrode assembly 120 , a terminal post 130 , a first insulating member 140 and a sealing member 150 .

[0054] See also Figure 1Housing 110 includes an end wall 111 and a side wall 112 surrounding end wall 111. The connection between end wall 111 and side wall 112 can be achieved in a variety of ways, such as integral stamping, integral casting, or separate welding, as long as a stable sealing and electrical connection are achieved. The shape of side wall 112 is not limited and can be cylindrical, prismatic, or any other closed-loop contour that matches end wall 111.

[0055] For example, in this embodiment, the outer edge of the end wall 111 is circular, and the side wall 112 is cylindrical and surrounds the outer edge of the end wall 111. A circular opening 113 is formed at the end of the side wall 112 facing away from the end wall 111. A receiving cavity is formed in the housing 110 enclosed by the end wall 111 and the side wall 112 for accommodating the electrode assembly 120, electrolyte, and other necessary battery components.

[0056] See also Figure 1 and Figure 3 The electrode assembly 120 is disposed inside the housing 110. The electrode assembly 120 is the component where the electrochemical reaction occurs in the single cell 100. The housing 110 may contain one or more electrode assemblies 120. For example, in this embodiment, one electrode assembly 120 is disposed inside the housing 110. The electrode assembly 120 includes a pole piece and a separator 122, which are wound to form a wound structure. Specifically, in this embodiment, the electrode assembly 120 includes a positive pole piece 121, a separator 122, and a negative pole piece 123 axially wound around the housing 110.

[0057] See also Figure 3 The positive electrode sheet 121 includes a positive electrode current collector 1211 and a positive electrode active material layer coated on the positive electrode current collector 1211. A first coating area 1212 coated with the positive electrode active material layer and a first uncoated area 1213 not coated with the positive electrode active material layer are formed on the positive electrode current collector 1211. The first coating area 1212 and the first uncoated area 1213 are arranged axially along the shell 110. The first uncoated area 1213 extends to the outside of the diaphragm 122 at one end in the height direction of the single battery 100, and is bent toward the axis of the shell 110 to form a stacked positive electrode tab 125.

[0058] The negative electrode sheet 123 includes a negative electrode current collector 1231 and a negative electrode active material layer coated on the negative electrode current collector 1231. A second coating area 1232 coated with the negative electrode active material layer and a second uncoated area 1233 not coated with the negative electrode active material layer are formed on the negative electrode current collector 1231. The second coating area 1232 and the second uncoated area 1233 are arranged axially along the shell 110. The second uncoated area 1233 extends to the outside of the diaphragm 122 toward the other end in the height direction of the single cell 100, and is bent toward the axis of the shell 110 to form a stacked negative electrode tab 124.

[0059] The separator 122 is disposed between the positive electrode sheet 121 and the negative electrode sheet 123 to separate the positive electrode active material layer from the negative electrode active material layer. Taking the lithium-ion single cell 100 as an example, the positive electrode current collector 1211 can be made of aluminum, and the positive electrode active material layer includes a positive electrode active material, which can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, among others. The negative electrode current collector 1231 can be made of copper, and the negative electrode active material layer includes a negative electrode active material, which can be carbon or silicon, among others. The base material of the separator 122 can be polypropylene (PP) or polyethylene (PE), among others. To provide protection and insulation for the electrode assembly 120, an insulating film can also be coated on the outside of the electrode assembly 120. The insulating film can be made of PP, PE, polyethylene terephthalate (PET), polyvinyl chloride (PVC), or other polymer materials.

[0060] Furthermore, the positive electrode tab 125 of the present invention faces the end wall 111 or the opening 113, while the negative electrode tab 124 faces the other end of the housing 110. Figure 1 In this embodiment, the positive electrode tab 125 faces the end wall 111 and is electrically connected to the electrode post 130, causing the electrode post 130 to be positively charged. The negative electrode tab 124 faces the opening 113 and is electrically connected to the housing 110, causing the housing 110 to be negatively charged. However, in other embodiments, the negative electrode tab 124 may be connected to the electrode post 130, while the positive electrode tab 125 may be connected to the housing 110.

[0061] See also Figure 1 The single cell 100 may further include an end cap 114, which is sealed against the opening 113. The outer edge of the end cap 114 corresponds to the shape of the opening 113 and is connected to the side wall 112 to seal the opening 113. The end cap 114 may be installed in a manner including, but not limited to, mechanical sealing or welding. In this embodiment, the end cap 114 is sealed against the opening 113 using a mechanical seal.

[0062] See also Figure 1 and Figure 2The electrode post 130 is fixed to the end wall 111 and electrically connected to the electrode assembly 120. It should be noted that the end of the electrode post 130 facing the electrode assembly 120 can pass through the end wall 111 and be directly electrically connected to the positive electrode tab 125, or it can be indirectly electrically connected to the positive electrode tab 125 through the current collecting member 180. Optionally, in this embodiment, a current collecting member 180 is provided on the side of the electrode assembly 120 facing the end wall 111, and the electrode post 130 is electrically connected to the positive electrode tab 125 through the current collecting member 180.

[0063] See also Figure 2 The electrode 130 includes a body 131, a first stopper 132, and a second stopper 133. The first stopper 132 and the second stopper 133 are respectively disposed at opposite ends of the body 131 in the height direction and extend radially from the outer periphery of the body 131 to the outer periphery of the end wall 111. A mounting hole 1111 is defined in the end wall 111, through which the body 131 extends. The end of the body 131 facing away from the electrode assembly 120 is connected to the first stopper 132, meaning that the first stopper 132 is located outside the housing 110. The end of the body 131 facing the electrode assembly 120 is connected to the second stopper 133, meaning that the second stopper 133 is located inside the housing 110. The cross-sections of the first and second stopper 132, 133 may be circular, square, prismatic, or other special-shaped profiles that enable stable electrical conduction, but this embodiment is not limited thereto. Optionally, to facilitate the production and processing of the pole 130 , in this embodiment, the outer contours of the first limiting portion 132 and the second limiting portion 133 are both circular contours coaxially arranged with the column portion 131 .

[0064] See also Figure 2 The end wall 111 is sandwiched between the first limiting portion 132 and the second limiting portion 133. To achieve an insulated connection between the electrode post 130 and the end wall 111, a first insulating member 140 is provided between the first limiting portion 132 and the end wall 111. At least a portion of the first insulating member 140 is sandwiched between the outer side of the end wall 111 (the side of the end wall 111 facing away from the electrode assembly 120) and the first limiting portion 132 to achieve insulation between the outer side of the end wall 111 and the first limiting portion 132. A second insulating member 170 is provided between the second limiting portion 133 and the end wall 111. At least a portion of the second insulating member 170 is sandwiched between the inner side of the end wall 111 (the side of the end wall 111 facing the electrode assembly 120) and the second limiting portion 133 to achieve insulation between the second limiting portion 133 and the end wall 111.

[0065] See also Figure 4The first insulating member 140 includes a first portion 142 and a second portion 141 connected to the first portion 142. The first portion 142 is sandwiched between the end wall 111 and the first limiting portion 132, and the second portion 141 extends into the mounting hole 1111, that is, is located between the hole wall of the mounting hole 1111 and the outer peripheral surface of the column portion 131.

[0066] See also Figure 4 The seal 150 is arranged on the inner side of the end wall 111 and is sandwiched between the end wall 111 and the second limiting portion 133. The seal 150 is sleeved on the outer periphery of the column portion 131, and the inner edge of the seal 150 abuts against the outer peripheral surface of the column portion 131. During the extrusion assembly process of the seal 150, sealing contact surfaces are formed at the contact positions of the seal 150 with the end wall 111 and the contact positions of the seal 150 with the pole 130, so as to achieve a sealed connection between the pole 130 in the mounting hole 1111. Among them, at least one accommodating cavity 160 is enclosed between one or more of the second portion 141, the seal 150 and the hole wall of the mounting hole 1111, and the outer peripheral surface of the column portion 131. Specifically, in one embodiment, only one accommodating cavity 160 can be enclosed between the second portion 141, the seal 150 and the hole wall of the mounting hole 1111. In another embodiment, a single accommodating cavity 160 may be formed between only the second portion 141, the sealing member 150, and the outer circumference of the column portion 131. In other embodiments, a single accommodating cavity 160 may be formed between the second portion 141, the sealing member 150, and the wall of the mounting hole 1111, while another accommodating cavity 160 may be formed between the second portion 141, the sealing member 150, and the outer circumference of the column portion 131.

[0067] In this embodiment, at least one accommodating cavity 160 is formed between the second portion 141 of the first insulating member 140, the sealing member 150, the hole wall of the mounting hole 1111, and the outer peripheral surface of the column portion 131. Therefore, during the assembly and extrusion process of the sealing member 150, the end wall 111, the pole 130, and the first insulating member 140, the gas on the sealing contact surfaces formed between the sealing member 150 and the end wall 111, and between the sealing member 150 and the pole 130 can enter the accommodating cavity 160 without being retained at the sealing contact surfaces. Therefore, by using the accommodating cavity 160 to store the gas discharged during the assembly and extrusion process of the sealing member 150, the residual gas on the sealing contact surfaces can be effectively reduced, thereby improving the sealing reliability of the sealing member 150 and reducing the risk of sealing failure between the pole 130 and the housing 110.

[0068] In one embodiment of the single cell 100 of the present invention, at least one accommodating cavity 160 includes a first accommodating cavity 161 formed by the second portion 141, the sealing member 150, and the outer circumference of the column portion 131, and / or a second accommodating cavity 162 formed by the second portion 141, the sealing member 150, and the wall of the mounting hole 1111. In one embodiment, please refer to Figure 5 , the accommodating cavity 160 only includes a first accommodating cavity 161 formed by the second portion 141, the sealing member 150 and the outer peripheral surface of the column portion 131. It should be noted that along the circumferential direction of the column portion 131, the sealing member 150 and the outer peripheral surface of the column portion 131 may not be in contact with each other in the entire circle, that is, a first accommodating cavity 161 that is approximately annular is formed between the second portion 141, the sealing member 150 and the outer peripheral surface of the column portion 131. The sealing member 150 and the outer peripheral surface of the column portion 131 may also be partially in contact or partially non-contact, that is, one or more non-annular first accommodating cavities 161 are formed between the second portion 141, the sealing member 150 and the outer peripheral surface of the column portion 131.

[0069] In another embodiment, see Figure 4 The accommodating cavity 160 only includes a second accommodating cavity 162 formed by the second portion 141, the sealing member 150 and the wall of the mounting hole 1111. It should be noted that along the circumferential direction of the mounting hole 1111, the sealing member 150 and the wall of the mounting hole 1111 may not be in contact with each other in the entire circle, that is, a second accommodating cavity 162 that is approximately annular is formed between the second portion 141, the sealing member 150 and the wall of the mounting hole 1111. The sealing member 150 and the wall of the mounting hole 1111 may also be in partial contact or non-contact, that is, one or more non-annular second accommodating cavities 162 are formed between the second portion 141, the sealing member 150 and the wall of the mounting hole 1111.

[0070] In some other embodiments, see Figure 6 The accommodating cavity 160 includes a first accommodating cavity 161 formed by the second portion 141, the sealing member 150, and the outer circumference of the column portion 131, and a second accommodating cavity 162 formed by the second portion 141, the sealing member 150, and the wall of the mounting hole 1111. It should be noted that in this embodiment, the number of first accommodating cavities 161 and second accommodating cavities 162 is not limited, and one or more accommodating cavities may be provided. The shapes of the first accommodating cavity 161 and the second accommodating cavity 162 are not limited, and may be annular or other shapes.

[0071] By providing the first accommodating cavity 161 and / or the second accommodating cavity 162, during the assembly and extrusion process of the seal 150 with the end wall 111, the pole 130, and the first insulating member 140, gas on the sealed contact surfaces formed between the seal 150 and the end wall 111, and between the seal 150 and the pole 130 can enter the first accommodating cavity 161 and / or the second accommodating cavity 162, thereby preventing gas from being retained at the sealed contact surfaces. This improves the sealing reliability of the seal 150 and reduces the risk of sealing failure between the pole 130 and the housing 110.

[0072] See also Figure 5 In one embodiment of the single cell battery 100 of the present invention, the second portion 141 abuts against the wall of the mounting hole 1111, meaning that no second accommodating cavity 162 exists between the second portion 141 and the wall of the mounting hole 1111. A first accommodating cavity 161 is defined between the second portion 141, the seal 150, and the outer circumference of the column portion 131. The number and shape of the first accommodating cavities 161 are not limited.

[0073] The first accommodating cavity 161, formed between the second portion 141, the seal 150, and the outer circumference of the column portion 131, can accommodate gas at the sealed contact surfaces formed between the seal 150 and the end wall 111, and between the seal 150 and the terminal 130, reducing the probability of gas stagnation at the sealed contact surfaces and improving the sealing performance of the seal 150. Furthermore, compared to the second accommodating cavity 162, the electrolyte within the single cell 100 has a longer diffusion path to reach the accommodating cavity 160 through the sealed interface between the seal 150 and the end wall 111, or the sealed interface between the seal 150 and the second limiting portion 133, thereby further reducing the probability of leakage at the installation location of the terminal 130.

[0074] See also Figure 7 In one embodiment of the single cell battery 100 of the present invention, a first accommodating cavity 161 is defined between the second portion 141, the seal 150, and the outer circumference of the column portion 131. A second accommodating cavity 162 is defined between the second portion 141, the seal 150, and the wall of the mounting hole 1111. A gap 163 is formed between the second portion 141 and the seal 150, and the first accommodating cavity 161 and the second accommodating cavity 162 are interconnected through the gap 163. It should be noted that the specific method for forming the gap 163 is not limited. The gap 163 can be formed by the surface of the seal 150 facing away from the electrode assembly 120 not contacting the surface of the second portion 141 facing the electrode assembly 120. Alternatively, a groove extending radially through the second portion 141 along the mounting hole 1111 is provided on the side of the second portion 141 facing the electrode assembly 120, thereby forming the aforementioned gap 163.

[0075] By providing a gap 163 between the second portion 141 and the sealing member 150 and interconnecting the first and second accommodating chambers 161 and 162 through the gap 163, this arrangement increases the overall volume of the accommodating chamber 160, thereby accommodating more gas and further ensuring gas retention on the sealing contact surface, thereby maintaining the sealing performance of the sealing member 150. Furthermore, this interconnected design prevents localized pressure buildup caused by excessive gas within the first or second accommodating chambers 161 and 162, thereby ensuring uniform pressure within the housing 110 and improving the stability of the overall mounting structure of the single cell 100.

[0076] See also Figure 8 In one embodiment of the single cell battery 100 of the present invention, the side of the seal 150 facing away from the second limiting portion 133 at least partially extends into the accommodating cavity 160. Specifically, the side of the seal 150 facing away from the second limiting portion 133 includes a protruding structure 151, which extends into the accommodating cavity 160. The protruding structure 151 may extend into the first accommodating cavity 161, or into the second accommodating cavity 162, or may partially extend into the first accommodating cavity 161 and partially into the second accommodating cavity 162. The protruding structure 151 may completely fill the accommodating cavity 160 or partially fill the space in the accommodating cavity 160. It should be noted that the protruding structure 151 is a structural feature formed by extrusion during the assembly process of the seal 150. Therefore, an additional sealing contact area is formed between the protruding structure 151 and the cavity walls of the first accommodating cavity 161 and / or the second accommodating cavity 162.

[0077] In this embodiment, because the side of the sealing member 150 facing away from the second limiting portion 133 at least partially extends into the accommodating cavity 160, the portion extending into the accommodating cavity 160 can form an additional sealing contact surface with the cavity wall of the accommodating cavity 160. This design can form multiple seals along the electrolyte leakage path, thereby increasing the difficulty of electrolyte leakage, and thus further improving the sealing performance between the electrode 130 and the housing 110.

[0078] See also Figure 6In an embodiment of the single cell battery 100 of the present invention, the width dimension of the first accommodating cavity 161 is W1, the width dimension of the second accommodating cavity 162 is W2, and W1>W2. Specifically, in this embodiment, the first accommodating cavity 161 is an annular cavity structure arranged around the center of the column portion 131. The first accommodating cavity 161 and the outer peripheral surface of the column portion 131 can be coaxial or non-coaxial. The second accommodating cavity 162 is an annular cavity structure arranged around the center of the mounting hole 1111. The second accommodating cavity 162 and the mounting hole 1111 can be coaxial or non-coaxial. The width dimension W1 of the first accommodating cavity 161 is the minimum radial width dimension of the first accommodating cavity 161. The width dimension W2 of the second accommodating cavity 162 is the maximum radial width dimension of the second accommodating cavity 162.

[0079] By setting the width W1 of the first accommodating cavity 161 to be larger than the width W2 of the second accommodating cavity 162, on the one hand, a portion of the space in the first accommodating cavity 161 can store gas, thereby ensuring the sealing performance of the sealing member 150. On the other hand, if the size of the second accommodating cavity 162 is too large, the installation coaxiality between the first insulating member 140 and the end wall 111 and the terminal 130 will be easily reduced. This will cause a large difference in the circumferential crimping area and riveting force of the first insulating member 140 during the riveting process of the second limiter 132, resulting in a poor local sealing effect.

[0080] For further information, please refer to Figure 8 In one embodiment of the single cell 100 of the present invention, 0.2 mm ≤ W1 ≤ 0.5 mm. For example, W1 may be 0.2 mm, 0.35 mm, or 0.5 mm. 0 mm ≤ W2 ≤ 0.15 mm. For example, W2 may be 0.075 mm or 0.15 mm. In another embodiment, 0.2 mm ≤ W1 ≤ 0.5 mm. For example, W1 may be 0.2 mm, 0.35 mm, or 0.5 mm. In other embodiments, 0 mm ≤ W2 ≤ 0.15 mm. For example, W2 may be 0.075 mm or 0.15 mm.

[0081] By limiting the range of 0.2mm≤W1≤0.5mm, the size of first accommodating cavity 161 can be further optimized, ensuring that first accommodating cavity 161 has sufficient space to store gas generated during the assembly process of seal 150, thereby improving the sealing performance of seal 150. At the same time, by limiting the range of 0mm≤W2≤0.15mm, the thickness of second portion 141 can be ensured to meet the insulation performance requirements between column portion 131 and the wall of mounting hole 1111.

[0082] See also Figure 9 and Figure 14In one embodiment of the single cell 100 of the present invention, the side of the second limiting portion 133 facing the end wall 111 includes an abutting flat surface 1331. The abutting flat surface 1331 transitions to the side of the outer circumferential surface of the cylindrical portion 131 facing the electrode assembly 120 via an arcuate surface 134. The inner edge of the sealing member 150 at least partially abuts the arcuate surface 134. It should be noted that when the sealing member 150 abuts the arcuate surface 134, it deforms to conform to the arcuate surface 134, forming an arc-shaped contact surface.

[0083] In this embodiment, the inner edge of the seal 150 abuts against the arc surface 134 to form an arcuate contact surface. This arcuate contact surface design increases the contact area between the seal 150 and the column portion 131, thereby improving the sealing performance between the seal 150 and the surface of the pole 130. At the same time, the curvature of the arcuate contact surface allows gas to flow better along the arcuate surface into the accommodating cavity 160 during the contact process, thereby reducing gas retention at the sealing contact surface, thereby further improving the sealing effect of the seal 150.

[0084] See also Figure 8 In an embodiment of the single cell 100 of the present invention, a chamfer 1112 is provided at the edge of the opening of the mounting hole 1111 on the side facing the electrode assembly 120. The chamfer 1112 may be an oblique angle, a rounded angle, or the like. Optionally, in this embodiment, the chamfer 1112 is a rounded angle. By providing the chamfer 1112 at the edge of the opening of the mounting hole 1111 on the side facing the electrode assembly 120, the chamfer 1112 can provide a smooth transition during the process of the seal 150 being squeezed into the second accommodating cavity 162, effectively guiding the seal 150 to smoothly enter the second accommodating cavity 162, thereby extending the effective sealing area of ​​the sealing contact surface and extending the path length of the electrolyte entering the accommodating cavity 160, thereby reducing the risk of electrolyte leakage and improving the sealing performance of the seal 150. At the same time, the chamfer 1112 can also blunt the edge of the opening of the mounting hole 1111, reduce sharp corners, and avoid scratches, cracks and other damages to the seal 150 caused by the edge of the opening of the mounting hole 1111, thereby further maintaining the structural integrity of the seal 150 and ensuring its sealing performance.

[0085] See also Figure 9In one embodiment of the single cell battery 100 of the present invention, the projections of the first limiting portion 132, the first insulating member 140, and the end wall 111 along a predetermined direction overlap. The minimum width of the overlapping region is L1, and 0.3 mm ≤ L1 ≤ 1.5 mm. For example, L1 can be 0.3 mm, 0.9 mm, or 1.5 mm. The predetermined direction is the thickness direction of the end wall 111. Specifically, the overlapping region is a substantially circular ring structure. The minimum width L1 of the overlapping region refers to the distance between the wall of the mounting hole 1111 and the outer edge contour of the first limiting portion 132 along the radial direction of the mounting hole 1111.

[0086] By limiting the minimum width L1 of the overlapping area to within the range of 0.3 mm ≤ L1 ≤ 1.5 mm, this arrangement ensures a sufficient crimping area between the first limiter 132, the first insulating member 140, and the end wall 111. This not only improves the mechanical connection strength between the terminal 130 and the end wall 111, but also enhances the stability of the connection structure between the terminal 130, the seal 150, and the end wall 111. This further improves the uniformity of the contact pressure between the seal 150, the end wall 111, and the terminal 130, thereby improving the reliability and stability of the sealing performance.

[0087] See also Figure 2 and Figure 9 In one embodiment of the single cell 100 of the present invention, the single cell 100 further includes a second insulating member 170, which is disposed on the side of the end wall 111 facing the electrode assembly 120 and at least partially extends between the second limiting portion 133 and the end wall 111. An annular lap surface 171 is formed between the second limiting portion 133 and the second insulating member 170. Along the radial direction of the mounting hole 1111, the minimum width of the annular lap surface 171 is L2, and L2 ≥ 2.5 mm. It should be noted that the annular lap surface 171 can be an annular structure of equal width or an annular structure of unequal width, as long as the minimum width L2 of the annular lap surface 171 can be ensured to be ≥ 2.5 mm.

[0088] In this embodiment, the second limiting portion 133 overlaps the second insulating member 170, thereby ensuring that there is a sufficient extrusion overlap area between the second insulating member 170 and the second limiting portion 133 on the inner side of the end wall 111, thereby ensuring that stable and reliable extrusion contact is formed between the pole 130 and the second insulating member 170. This not only provides stable and reliable insulation performance between the second limiting portion 133, the pole 130 and the end wall 111, but also ensures the stability of the insulation performance between the pole 130 and the housing 110. At the same time, because the installation structure between the second limiting portion 133 and the end wall 111 is relatively stable, the force applied to the seal 150 sandwiched therebetween is also more stable and uniform, which is conducive to improving the stability of the sealing performance of the seal 150. By limiting the minimum width L2 of the annular overlapping surface 171 to ≥2.5 mm, the possibility of electrolyte diffusing from the interface between the second insulating member 170 and the second limiting portion 133 to the vicinity of the seal 150 is reduced, thereby achieving an auxiliary sealing effect.

[0089] See also Figures 10 to 12 In one embodiment of the single cell 100 of the present invention, the side of the end wall 111 facing away from the electrode assembly 120 includes a recess 1113, the recess 1113 is recessed toward the side of the electrode assembly 120, the mounting hole 1111 passes through the bottom wall of the recess 1113, and the first insulating member 140 is at least partially accommodated in the recess 1113. The shape of the recess 1113 matches the shape of the first insulating member 140 to ensure that the side of the first insulating member 140 facing the electrode assembly 120 can fit the bottom wall of the recess 1113. The mounting hole 1111 is located in the center area of ​​the recess 1113, that is, it is coaxial with the recess 1113. In other embodiments, the mounting hole 1111 can also be coaxial with the recess 1113, which needs to be determined according to the installation position requirements of the terminal 130.

[0090] See also Figures 10 to 12 On the side of the end wall 111 facing the electrode assembly 120, the bottom wall of the recess 1113 protrudes toward the electrode assembly 120 to form a protrusion 1114. The protrusion 1114 at least partially abuts against the seal 150. Specifically, the protrusion 1114 includes a top wall 1115, which abuts against the seal 150 to form a sealing contact surface between the end wall 111 and the seal 150.

[0091] Because the recessed portion 1113 and raised portion 1114 provided on the end wall 111 can form a rib-like effect, the overall strength of the end wall 111 can be enhanced, improving its ability to resist deformation under external pressure or internal gas expansion. This helps maintain the stability of the shape and installation position of the seal 150 during the operation of the single cell 100, reducing seal failure caused by deformation of the end wall 111, thereby improving the stability and reliability of the sealing performance of the single cell 100. In addition, the provision of the recessed portion 1113 can also reduce the height of the first insulating member 140 protruding from the outside of the end wall 111, making the installation structure outside the end wall 111 more compact. At the same time, the provision of the raised portion 1114 can provide stable and reliable support for the seal 150, which is conducive to enhancing the stability and uniformity of the contact between the seal 150 and the end wall 111, thereby further improving the sealing performance at the installation position of the pole 130.

[0092] See also Figure 12 In one embodiment of the single cell 100 of the present invention, the depth of the recess 1113 along the thickness direction of the end wall 111 is h1, and 0.05mm≤h1≤1mm. For example, h1 can be 0.05mm, 0.5mm, or 1mm. If h1 is less than 0.05mm, the provision of the recess 1113 will not significantly enhance the strength of the end wall 111, and thus will not significantly enhance the sealing performance of the terminal 130. If h1 is greater than 1mm, the depth of the recess 1113 will be too large, which will reduce the structural strength of the end wall 111 at the location of the recess 1113. This may cause the end wall 111 to crack at the location of the recess 1113 when the pressure in the single cell 100 increases, before the explosion-proof valve opens, thereby affecting the pressure resistance of the single cell 100.

[0093] See also Figure 10 and Figure 12 In one embodiment of the single cell 100 of the present invention, the outer contour of the top wall 1115 is projected outside the outer contour of the seal 150 along the thickness direction of the end wall 111. The top wall 1115 can be coaxial with or non-coaxial with the seal 150, as long as the outer contour of the top wall 1115 is projected outside the outer contour of the seal 150. By positioning the outer contour of the top wall 1115 outside the outer contour of the seal 150, it is ensured that when the seal 150 contacts the end wall 111, the top wall 1115 of the protrusion 1114 always contacts the seal 150. This ensures uniformity and stability of the contact pressure between the seal 150 and the end wall 111, preventing problems such as overpressure or underpressure in the seal 150, and thereby improving the stability of the sealing performance at this location.

[0094] See also Figure 12In one embodiment of the single cell 100 of the present invention, the thickness of the end wall 111 is h2. On the side of the end wall 111 facing the electrode assembly 120, the height of the protrusion 1114 protruding from the end wall 111 is h3, and h3 ≥ (1 / 3) × h2. Specifically, the end wall 111 includes a main body 1116 and a protrusion 1114. The main body 1116 surrounds the periphery of the protrusion 1114 and is connected to the side wall 112 of the housing 110. The height h3 of the protrusion 1114 protruding from the end wall 111 is specifically the vertical distance between the bottom wall of the recess 1113 and the top wall 1115 of the protrusion 1114. By limiting the height h3 of the protrusion 1114 protruding from the end wall 111, and ensuring that h3 ≥ (1 / 3) × h2, this configuration prevents the protrusion 1114 from protruding too high, thereby affecting the height installation space of the electrode assembly 120 within the housing 110, thereby ensuring the volumetric energy density of the single battery 100. At the same time, the structural strength of the end wall 111 at the location of the protrusion 1114 is further ensured, reducing the adverse impact on the pressure resistance performance of the single battery 100.

[0095] See also Figure 2 and Figure 14 In one embodiment of the single cell 100 of the present invention, both the second stopper 133 and the first stopper 132 are revolved structures. Along the thickness direction of the end wall 111, the outer contour of the first stopper 132 lies within the outer contour of the second stopper 133. That is, the width of the first stopper 132 extending to the outer periphery of the columnar portion 131 is smaller than the width of the second stopper 133 extending to the outer periphery of the columnar portion 131. This arrangement allows the second stopper 133, with its larger width, to form a larger contact area with the end wall 111 on the inner side of the end wall 111, thereby facilitating a larger sealing contact area between the seal 150 and the end wall 111 and the second stopper 133, thereby improving the sealing performance of the seal 150. Furthermore, the larger width of the second stopper 133 also helps to improve the stability of the mounting structure between the second stopper 133 and the second insulating member 170, thereby enhancing the insulation stability between the second stopper 133 and the end wall 111.

[0096] See also Figures 13 to 15In an embodiment of the single cell 100 of the present invention, the first limiting portion 132 is a riveted flanging structure. The side of the pole 130 facing away from the electrode assembly 120 also includes a groove 135, and the groove 135 includes a groove sidewall 1351. The first limiting portion 132 is arranged around the outer periphery of the groove 135. The first limiting portion 132 includes a bending portion 1322 and an extension portion 1321, the bending portion 1322 connects the extension portion 1321 and the groove sidewall 1351, and the extension portion 1321 extends from the bending portion 1322 to the outer periphery of the end wall 111. Specifically, the first limiting portion 132 includes a planar section 1323 and a curved section 1324 that are interconnected on the side facing the electrode assembly 120, and the curved section 1324 connects the outer peripheral surface of the column portion 131 and the planar section 1323. In the thickness direction of the end wall 111, the area corresponding to the planar section 1323 is defined as the extension portion 1321, as shown in FIG. Figure 15 As shown in the area I in the middle, the remaining area of ​​the first limiting portion 132 is defined as a bending portion 1322 .

[0097] The thickness of the extension portion 1321 is less than the thickness of the bent portion 1322. It should be noted that the extension portion 1321 can have a uniform thickness or a unequal thickness. In this embodiment, the thickness of the extension portion 1321 is the maximum thickness of the extension portion 1321. The bent portion 1322 can have a uniform thickness or a unequal thickness. In this embodiment, the thickness of the bent portion 1322 is the minimum thickness of the bent portion 1322.

[0098] In some embodiments, a shaping device may be used to shape the riveted flange 132 one or more times during the bending process to ensure that the thickness of the riveted flange 132 meets the requirements of this application. Alternatively, the riveted flange 132 may be bent by designing its thickness to match that of the unbent flange 132, for example, by increasing the thickness from the outer end of the riveted flange 132 to the connection with the column portion 131.

[0099] In this embodiment of the battery cell 100, since the thickness of the extension portion 1321 is thinner than that of the bend portion 1322, the first stopper 132 can be locally thickened at the bend portion 1322. The increased thickness of the bend portion 1322 is equivalent to increasing the thickness of the first stopper 132 at the base of the bend. The thicker bend portion 1322 can better accommodate material deformation during the bending process, reducing cracks caused by insufficient material ductility. Furthermore, during the riveting process, since material deformation is primarily concentrated in the bend portion 1322, increasing the thickness of the bend portion 1322 effectively disperses stress, mitigates stress concentration, and further reduces the occurrence of cracks. On the one hand, reducing cracks strengthens the connection between the first stopper 132 and the end wall 111, thereby reducing the risk of mechanical strength degradation caused by cracks. On the other hand, reducing cracks can also reduce the conductive resistance of the terminal 130, thereby improving the stability of the electrical connection between the terminal 130 and the external electrical connector. In addition, as the connection strength between the first limiting portion 132 and the end wall 111 increases, the stability of the connection structure between the first limiting portion 132, the first insulating member 140, the end wall 111 and the sealing member 150 will also increase, which is also beneficial to further improve the sealing performance of the pole 130 at the mounting hole 1111.

[0100] See also Figure 16 In one embodiment of the single cell 100 of the present invention, a chamfer 13211 is provided at one end of the extension portion 1321 away from the bent portion 1322. The chamfer 13211 can be rounded, beveled, or otherwise formed. It should be noted that the chamfer 13211 can be formed during the bending process of the riveted flange 132 using a shaping device using one or more shaping processes. Alternatively, the chamfer 13211 can be formed directly on the outer edge of the riveted flange 132 through mechanical processing prior to the bending process.

[0101] During the riveting process, stress concentration is likely to occur at the outer edge of the riveted flange 132. By providing a chamfer 13211 at the end of the extension 1321 away from the bend 1322, that is, providing a chamfer 13211 at the outer edge of the riveted flange 132, this prevents the outer edge of the riveted flange 132 from contacting the external electrical connector when the top wall of the riveted flange 132 contacts the external electrical connector. This structural design can effectively prevent stress concentration at the outer edge of the riveted flange 132 from being transmitted to the electrical connection interface, thereby reducing the risk of contact resistance fluctuations, improving the long-term contact stability between the pole 130 and the external electrical connector, and ultimately improving the stability of the electrical connection.

[0102] See also Figure 14 and Figure 17In one embodiment of the single cell 100 of the present invention, the thickness of the second limiting portion 133 along the thickness direction of the end wall 111 is H, the outer radius of the second limiting portion 133 is R1, and 12 mm ≤ R1 ≤ 17 mm. For example, R1 can be 12 mm, 15 mm, or 17 mm, and 12 ≤ R1 / H ≤ 16.875. For example, the ratio between R1 and H can be 12, 14.5, 16.875, etc. It should be noted that the second limiting portion 133 can be of uniform or unequal thickness. In this embodiment, the thickness H of the second limiting portion 133 refers to the minimum thickness of the second limiting portion 133 (ignoring the effect of the chamfer at the outer edge of the second limiting portion 133).

[0103] During use of the single cell 100, when the internal pressure of the gas generated within the single cell 100 is too high, the terminal 130 will move toward the outside of the end wall 111 under the influence of the internal air pressure. If the strength and rigidity of the first limiting portion 133 are relatively low, the first limiting portion 133 will bend at its base, weakening the connection strength and sealing performance between the terminal and the housing. Furthermore, if the terminal 130 continues to move toward the outside of the end wall 111 under the influence of the internal air pressure, when the outer diameter of the bent first limiting portion 133 is smaller than the terminal mounting hole, the terminal 130 may break away from the housing 110 and fly out. Therefore, under the same internal pressure, the strength and rigidity of the first limiting portion 133 directly affect the axial displacement of the terminal 130 relative to the end wall 111, that is, the axial rigidity of the terminal 130.

[0104] It should be noted that when the thickness H of the first limiting portion 133 reaches 0.8 mm, the axial stiffness of the pole 130 can be effectively enhanced by optimizing the outer contour radius R1 of the first limiting portion 133. Under the condition of R1 ≥ 12 mm, the basic connection strength between the pole 130 and the end wall 111 can be guaranteed. If R2 exceeds 17 mm, when the internal pressure of the gas generated inside the single cell 100 is too high, the first limiting portion 133 may be easily deformed, causing the radial outer edge of the first limiting portion 133 to move toward the electrode assembly 120 side, and then it may be easy to directly or indirectly squeeze the electrode assembly 120, resulting in thermal runaway. If the thickness H of the first limiting portion 133 is too large, it will cause a loss of energy density of the single cell 100, and the improvement of the axial stiffness of the pole 130 will be limited.

[0105] The single cell 100 of the present invention achieves this by setting the outer radius R1 of the first limiting portion 133 located within the housing 110 to 12mm≤R1≤17mm, and ensuring that the ratio of R1 to H satisfies 12≤R1 / H≤16.875. This design ensures that the first limiting portion 133 has sufficient strength and rigidity to meet the axial connection strength requirements between the electrode 130 and the end wall 111, while also avoiding the increased risk of thermal runaway caused by squeezing the electrode assembly 120 due to an excessively large outer radius R1 of the first limiting portion 133. By rationally setting R1 and the R1 / H ratio, this embodiment allows the electrode 130 to have greater axial rigidity, thereby effectively reducing the limitations on the overall pressure resistance of the single cell 100 due to insufficient axial rigidity of the electrode 130, thereby improving the pressure resistance of the single cell 100.

[0106] During use of the single cell 100, when the internal pressure of the gas generated within the single cell 100 is too high, the terminal 130 will move toward the outside of the end wall 111 under the influence of the internal air pressure. If the strength and rigidity of the first limiting portion 133 are relatively low, the first limiting portion 133 will bend at its base, weakening the connection strength and sealing performance between the terminal and the housing. Furthermore, if the terminal 130 continues to move toward the outside of the end wall 111 under the influence of the internal air pressure, when the outer diameter of the bent first limiting portion 133 is smaller than the terminal mounting hole, the terminal 130 may break away from the housing 110 and fly out. Therefore, under the same internal pressure, the strength and rigidity of the first limiting portion 133 directly affect the axial displacement of the terminal 130 relative to the end wall 111, that is, the axial rigidity of the terminal 130.

[0107] It should be noted that when the thickness H of the first limiting portion 133 reaches 0.8 mm, the axial stiffness of the pole 130 can be effectively enhanced by optimizing the outer contour radius R1 of the first limiting portion 133. Under the condition of R1 ≥ 12 mm, the basic connection strength between the pole 130 and the end wall 111 can be guaranteed. If R2 exceeds 17 mm, when the internal pressure of the gas generated inside the single cell 100 is too high, the first limiting portion 133 may be easily deformed, causing the radial outer edge of the first limiting portion 133 to move toward the electrode assembly 120 side, and then it may be easy to directly or indirectly squeeze the electrode assembly 120, resulting in thermal runaway. If the thickness H of the first limiting portion 133 is too large, it will cause a loss of energy density of the single cell 100, and the improvement of the axial stiffness of the pole 130 will be limited.

[0108] When conducting simulation experiments, the influence of the sealing form of the opening of the single battery 100 on the ultimate pressure of the terminal 130 is ignored. For multiple groups of single batteries 100 with a diameter of 46 mm, the terminal 130 structure is as follows Figure 2As shown, the pole 130 is riveted to the first insulating member 140 via the second stopper 132. The riveting force causes the second stopper 132 and the end wall 111 to clamp the sealing ring 150, compressing it. Based on this, the ultimate pressure of the pole 130 flying out was simulated by varying the thickness and length of the first stopper 133. The simulation results are shown in Table 1:

[0109]

[0110] Table 1

[0111] By comparing Example 9 with Example 1, it can be seen that when the thickness of the first limiting portion 133 increases from 0.8 mm to 1.0 mm, the ultimate pressure resistance of the corresponding single battery 100 (i.e., the ultimate pressure at which the terminal 130 flies out) also increases accordingly. This shows that the thickness H of the first limiting portion 133 is a significant factor affecting the pressure resistance of the terminal 130. Increasing the thickness helps improve its ability to withstand pressure, thereby improving the pressure resistance of the single battery 100.

[0112] From Examples 1 to 7, it can be seen that the ultimate withstand voltage of the single cell 100 does not continuously increase with the length of the first limit portion 133. Analysis of the experimental data from Examples 1 to 12 shows that when the outer radius R1 of the first limit portion 133 is between 12 mm and 17 mm, and the value of R1 / H is between 12 and 16.875, the ultimate withstand voltage of the single cell 100 can meet the basic connection strength between the terminal 130 and the end wall 111. This indicates that setting R1 to 12 mm ≤ R1 mm ≤ 17 mm and 12 ≤ R1 / H ≤ 16.875 is relatively reasonable.

[0113] Analysis of the experimental data in Comparative Examples 1 and 2 shows that when the value of R1 is less than 12 mm and R1 / H is less than 12, the ultimate pressure required for the pole 130 to fly out is low, failing to meet the basic connection strength requirements between the pole 130 and the end wall 111. Furthermore, when the value of R1 is between 12 mm and 17 mm, but R1 / H is greater than 16.875, the ultimate pressure required for the pole 130 to fly out is also low, failing to meet the basic connection strength requirements between the pole 130 and the end wall 111.

[0114] The experimental data in Table 1 above demonstrates that the present invention's single cell 100 achieves this by setting the outer radius R1 of the first retaining portion 133 within the housing 110 to 12 mm ≤ R1 ≤ 17 mm, and ensuring that the ratio of R1 to H satisfies 12 ≤ R1 / H ≤ 16.875. This design ensures that the first retaining portion 133 possesses sufficient strength and rigidity to meet the axial connection strength requirements between the terminal 130 and the end wall 111, while also preventing the increased risk of thermal runaway caused by the excessively large outer radius R1 of the first retaining portion 133 squeezing the electrode assembly 120 during the ejection of the terminal 130. By rationally setting R1 and the R1 / H ratio, this embodiment provides the terminal 130 with greater axial rigidity, effectively reducing the limitations on the overall pressure resistance of the single cell 100 due to insufficient axial rigidity of the terminal 130, thereby improving the pressure resistance of the single cell 100.

[0115] See also Figure 18 In one embodiment of a battery pack 200 of the present invention, the battery pack 200 includes a housing 210 and at least one single battery cell 100. The housing 210 includes a first housing portion 211 and a second housing portion 212. The first housing portion 211 and the second housing portion 212 overlap to form a storage space. Multiple single batteries 100 are housed within the storage space. The multiple single batteries 100 can be connected in series and / or in parallel. The battery pack 200 can be, for example, a battery module, a battery pack, or the like.

[0116] See also Figure 19In one example of an electronic device 300 of the present invention, the electronic device 300 includes a working unit 310 and a battery pack 200. The working unit 310 is electrically connected to the battery pack 200 to obtain electrical energy. The working unit 310 can be a unit component that can obtain electrical energy from the battery pack 200 and perform corresponding operations, such as the blade rotation unit of a fan, the dust collection unit of a vacuum cleaner, or the wheel drive unit of an electric vehicle. The electronic device 300 can be a vehicle, a mobile phone, a portable device, a laptop computer, a ship, a spacecraft, an electric toy, an electric tool, etc. Vehicles can be fuel vehicles, gas vehicles or new energy vehicles. New energy vehicles can be pure electric vehicles, hybrid 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.; power tools include metal cutting power tools, grinding power tools, assembly power tools and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators and electric planers, etc. The embodiment of the present invention does not impose any special restrictions on the above-mentioned electronic device 300. In one embodiment of the electronic device 300 of the present invention, the electronic device 300 is a vehicle, the working part 310 is the body of the vehicle, and the battery pack 200 is fixedly installed on the body, thereby providing driving force for the vehicle to realize the operation of the vehicle.

[0117] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A single battery, characterized in that: include: a housing, the housing comprising an end wall, the end wall comprising a mounting hole; an electrode assembly, housed in the housing; an electrode post, fixed to the end wall and electrically connected to the electrode assembly, the electrode post comprising a column portion, a first limiting portion, and a second limiting portion; the column portion passes through the mounting hole, the first limiting portion is located outside the shell and extends from the column portion to the outer periphery of the end wall, and the second limiting portion is located inside the shell and extends from the column portion to the outer periphery of the end wall; a first insulating member, the first insulating member comprising a first portion disposed between the first limiting portion and the end wall, and a second portion connected to the first portion, wherein the second portion extends into the mounting hole; a sealing member, sandwiched between the end wall and the second limiting portion, with an inner edge of the sealing member abutting against an outer peripheral surface of the column portion; The second portion and the sealing member are enclosed with one or more of the following to form at least one accommodating cavity: The hole wall of the mounting hole, or The outer peripheral surface of the column portion.

2. The single cell according to claim 1, characterized in that: At least one of the accommodating cavities includes a first accommodating cavity formed by the second part, the sealing member and the outer peripheral surface of the column portion, and / or a second accommodating cavity formed by the second part, the sealing member and the hole wall of the mounting hole.

3. The single cell according to claim 2, characterized in that: The second portion is in contact with the hole wall of the mounting hole, and the first accommodating cavity is formed between the second portion, the sealing member and the outer peripheral surface of the column portion.

4. The single cell according to claim 1, characterized in that: At least one of the accommodating cavities includes a first accommodating cavity formed by the second part, the seal and the outer peripheral surface of the column part, and a second accommodating cavity formed by the second part, the seal and the hole wall of the mounting hole, and the first accommodating cavity and the second accommodating cavity are connected through the gap between the second part and the seal.

5. The single cell according to claim 1, characterized in that: A side of the sealing member facing away from the second limiting portion at least partially extends into the accommodating cavity.

6. The single cell according to claim 1, characterized in that: At least one of the accommodating cavities includes a first accommodating cavity formed by the second part, the seal and the outer peripheral surface of the column part, and a second accommodating cavity formed by the second part, the seal and the hole wall of the mounting hole; the width dimension of the first accommodating cavity is W1, the width dimension of the second accommodating cavity is W2, and W1>W2.

7. The single cell according to claim 6, characterized in that: 0.2mm≤W1≤0.5mm; and / or, 0mm≤W2≤0.15mm.

8. The single cell according to claim 1, characterized in that: The second limiting portion includes an abutting plane on a side facing the end wall. The abutting plane is transitionally connected to the outer peripheral surface of the cylindrical portion through an arc surface, and the inner edge of the sealing member at least partially abuts against the arc surface.

9. The single cell according to claim 1, characterized in that: The mounting hole is provided with a chamfer at the edge of the hole facing the electrode assembly.

10. The single cell according to claim 1, characterized in that: There is an overlapping area among the projections of the first limiting portion, the first insulating member and the end wall along a predetermined direction, the minimum width of the overlapping area is L1, and 0.3mm≤L1≤1.5mm. The predetermined direction is the thickness direction of the end wall.

11. The single cell according to claim 1, characterized in that: The single cell battery also includes a second insulating member, which is arranged on the side of the end wall facing the electrode assembly, and at least partially extends between the second limiting portion and the end wall, and forms an annular overlapping surface with the second limiting portion; the minimum width of the annular overlapping surface is L2, and L2 ≥ 2.5 mm.

12. The single cell according to claim 1, characterized in that: The side of the end wall facing away from the electrode assembly includes a recess, the recess is recessed toward the side of the electrode assembly, the mounting hole passes through the bottom wall of the recess, and the first insulating member is at least partially accommodated in the recess; on the side of the end wall facing the electrode assembly, the bottom wall of the recess protrudes toward the side of the electrode assembly to form a convex portion, and the convex portion abuts against the sealing member.

13. The single cell according to claim 12, characterized in that: Along the thickness direction of the end wall, the depth of the recess is h1, and 0.05 mm ≤ h1 ≤ 1 mm.

14. The single cell according to claim 12, characterized in that: The convex portion includes a top wall, which abuts against the sealing member; along the thickness direction of the end wall, the outer contour projection of the top wall is located outside the outer contour projection of the sealing member.

15. The single cell according to claim 14, characterized in that: The thickness of the end wall is h2. On the side of the end wall facing the electrode assembly, the height of the protrusion protruding from the end wall is h3, and h3 ≥ (1 / 3) × h2.

16. The single cell according to claim 1, characterized in that: The first limiting portion and the second limiting portion are both rotating body structures. Along the thickness direction of the end wall, the outer contour projection of the first limiting portion is located within the outer contour projection of the second limiting portion.

17. The single cell according to claim 1, characterized in that: The first limiting portion is a riveted flange, and the side of the pole facing away from the electrode assembly also includes a groove, and the first limiting portion is arranged around the outer periphery of the groove; the groove includes a groove side wall, and the first limiting portion includes a bent portion and an extension portion, the bent portion connects the extension portion and the groove side wall, and the extension portion extends from the bent portion toward the outer peripheral edge of the end wall; wherein, the thickness of the extension portion is less than the thickness of the bent portion.

18. The single cell according to claim 1, characterized in that: The end wall is clamped between the first limiting portion and the second limiting portion. Along the thickness direction of the end wall, the thickness of the second limiting portion is H, the outer contour radius of the second limiting portion is R1, and 12mm≤R1≤17mm, 12≤R1 / H≤16.

875.

19. A battery pack, characterized in that: A single cell comprising the single cell according to any one of claims 1 to 18.

20. An electronic device, characterized in that: A battery pack comprising the battery pack of claim 19.

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