Secondary battery, battery pack, and electronic device

Abstract

The present application discloses a secondary battery, a battery pack and an electronic device, the secondary battery comprising: a housing having a first polarity, the housing comprising an end wall and a side wall surrounding the end wall, the end wall having a pole hole; the pole has second polarity opposite to the first polarity, the pole penetrates through the pole hole and is insulated from the end wall, a first flange and a second flange are arranged at the opposite ends, in the axial direction of the pole hole, of the pole respectively, the pole clamps the end wall through the first flange and the second flange to be fixed, and the second flange is riveted with the end wall; at least one part of the elastic insulating part is clamped between the second flange and the end wall; the melting point of the heat-resistant insulating part is higher than that of the elastic insulating part, and at least one part of the heat-resistant insulating part is located between the second flange and the end wall and clamped between the elastic insulating part and the end wall. According to the technical scheme, at least secondary short circuit of the parallel battery cells can be prevented.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a secondary battery, battery pack, and electronic device. Background Technology

[0002] In the field of new energy power batteries, secondary batteries (such as cylindrical batteries) mainly include electrode assemblies, casings, covers, and terminals. Electrode assemblies consist of positive and negative electrode plates, and a separator located between them. These positive and negative electrode plates and the separator are stacked and wound to form the electrode assembly, which is then placed inside the casing and sealed by the cover. Terminals pass through the casing and are electrically connected to the corresponding tabs of the electrode assembly, while the casing is electrically connected to the other tab. Typically, an insulating assembly is required between the terminals and the casing to ensure insulation. However, existing secondary batteries still require further improvement in insulation performance. Utility Model Content

[0003] To address the above problems, this application proposes a secondary battery, battery pack, and electronic device that can at least prevent secondary short circuits in parallel-connected cells.

[0004] According to one aspect of this application, a secondary battery is provided, comprising: a housing having a first polarity, the housing including an end wall and a side wall surrounding the end wall, the end wall having an electrode post hole; an electrode post having a second polarity opposite to the first polarity, the electrode post passing through the electrode post hole and being insulated from the end wall, the opposite ends of the electrode post along the axial direction of the electrode post hole respectively having a first flange and a second flange, the electrode post clamping the end wall for fixation by the first flange and the second flange, wherein the first flange is riveted to the end wall; an elastic insulating member, at least a portion of the elastic insulating member being clamped between the second flange and the end wall; and a heat-resistant insulating member, the melting point of the heat-resistant insulating member being higher than the melting point of the elastic insulating member, at least a portion of the heat-resistant insulating member being located between the second flange and the end wall and clamped between the elastic insulating member and the end wall.

[0005] In some embodiments, the second flange is located on the side of the end wall facing the outside of the housing.

[0006] In some embodiments, the heat-resistant insulation element is bonded to the end wall.

[0007] In some embodiments, the heat-resistant insulating member includes a first portion and a second portion, the first portion surrounding at least a lower portion of the elastic insulating member on one side opposite to the axis of the pole hole, and the second portion being connected to the first portion and located between the elastic insulating member and the end wall.

[0008] In some embodiments, the heat-resistant insulation extends beyond the second flange along the radial direction of the pole hole and in the axial direction away from the pole hole.

[0009] In some embodiments, the surface of the end wall facing the outside of the case includes a recess provided around the pole post hole, the heat-resistant insulator is disposed in the recess, and a side wall of the recess restricts radial movement of the heat-resistant insulator in the recess along the pole post hole.

[0010] In some embodiments, the side of the heat-resistant insulator facing away from the axis of the pole post hole is covered by the elastic insulator.

[0011] In some embodiments, the elastic insulator includes a first portion surrounding at least a portion of the outer peripheral surface of the second flange and a side of the heat-resistant insulator, and a second portion extending from the first portion toward the axis of the pole post hole, at least a portion of the heat-resistant insulator being sandwiched between the second portion and the end wall.

[0012] In some embodiments, the outer peripheral surface of the second flange includes a lower side wall and an upper side wall, the lower side wall being closer to the end wall than the upper side wall, the lower side wall being recessed relative to the upper side wall toward the axis of the pole post hole to define a recessed portion, and the second portion of the elastic insulator extending into the recessed portion.

[0013] In some embodiments, the inner diameter of the heat-resistant insulator is smaller than the outer diameter of the second flange at the lower side wall.

[0014] In some embodiments, the second flange and the second portion of the elastic insulator overlap in the axial direction of the pole post hole, and the size a of the overlapping region in the radial direction of the pole post hole is greater than 0.3 mm.

[0015] In some embodiments, the portion of the second flange overlapping with the second portion has a thickness d in the axial direction, where d ≥ 0.5 mm.

[0016] In some embodiments, the pole post further includes a pole post portion passing through the pole post hole and connecting the first flange and the second flange, and wherein the absolute value of the difference between the inner diameter of the heat-resistant insulator and the outer diameter of the heat-resistant insulator is greater than the absolute value of the difference between the diameter of the pole post hole and the diameter of the columnar portion.

[0017] In some embodiments, the secondary battery further includes a sealing ring surrounding the columnar portion of the pole post passing through the pole post hole and located between the second flange and the end wall, and wherein the distance between the heat-resistant insulator and the sealing ring in the radial direction of the pole post hole is greater than the distance between the elastic insulator and the sealing ring.

[0018] In some embodiments, the heat-resistant insulator and the sealing ring each have a thickness in the axial direction of the pole post hole, wherein the thickness of the heat-resistant insulator is 0.2 mm to 0.6 mm, and the ratio of the thickness of the heat-resistant insulator to the thickness of the sealing ring after compression is 0.25 to 1.

[0019] In some embodiments, the thickness of the heat-resistant insulator in the axial direction of the pole post hole is 0.01 mm to 1.5 mm.

[0020] In some embodiments, the material of the heat-resistant insulating component is one of ceramic, mica, or fire-resistant rubber.

[0021] In some embodiments, the melting point of the heat-resistant insulation component is greater than 600 degrees Celsius.

[0022] In some embodiments, the thickness of the heat-resistant insulating component is less than 1 mm, and the hardness of the heat-resistant insulating component is greater than 800 HV.

[0023] According to another aspect of this application, a battery pack is provided that includes the aforementioned secondary battery.

[0024] According to another aspect of this application, an electronic device is provided that includes the battery pack described above.

[0025] The beneficial technical effects of this utility model include:

[0026] By placing a heat-resistant insulating component, which is more heat-resistant than the first insulating component, between the non-riveted second flange of the terminal and the end wall of the casing, even if the first insulating component loses its insulating function due to thermal runaway, the heat-resistant insulating component can still maintain the insulation performance between the terminals with different polarities and the casing, preventing secondary short circuits in parallel cells. Furthermore, by placing the heat-resistant insulating component between the non-riveted second flange and the casing, the rupture of the heat-resistant insulating component due to riveting pressure can be avoided. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1A This is a schematic diagram of the structure of the positive electrode side of a secondary battery.

[0029] Figure 1B This is a schematic diagram of a secondary short-circuit test for multiple battery cells.

[0030] Figure 2 A perspective view of a secondary battery according to an embodiment of this application is shown.

[0031] Figure 3 A cross-sectional view of a secondary battery according to an embodiment of this application is shown.

[0032] Figure 4 It shows Figure 3 A partially enlarged schematic diagram of the terminal side of the secondary battery.

[0033] Figure 5 A partially enlarged schematic diagram of the terminal side of a secondary battery according to another embodiment of this application is shown.

[0034] Figure 6 A cross-sectional view of a secondary battery according to yet another embodiment of this application is shown.

[0035] Figure 7 It shows Figure 6 A magnified schematic diagram of a portion of the pole side.

[0036] Figure 8 It shows Figure 6 A magnified three-dimensional schematic diagram of a portion of the pole side.

[0037] Figure 9 A cross-sectional view of a secondary battery according to yet another embodiment of this application is shown.

[0038] Figure 10 A schematic diagram of an electronic device according to an embodiment of this application is shown. Detailed Implementation

[0039] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0040] The following disclosure provides numerous different embodiments or instances for implementing various features of the provided subject matter. Specific examples of elements and arrangements will be described below to simplify the present invention. These are merely examples and are not intended to limit the present invention. For example, in the following description, forming a first component above or on a second component may include embodiments where the first and second components are in direct contact, or embodiments where an additional component is formed between the first and second components such that the first and second components are not in direct contact. Furthermore, reference numerals and / or letters may be repeated in various instances of the present invention. Such repetition is merely for brevity and clarity and does not in itself indicate a relationship between the various embodiments and / or configurations discussed.

[0041] Furthermore, where there is no conflict, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0042] like Figure 1AAs shown, the design of the positive electrode post side of a secondary battery (such as the 46 series large cylindrical battery) is basically in the form of electrode post 50, upper plastic 31, sealing ring 70, and lower plastic 32. Among them, the upper plastic 31 and the lower plastic 32 are mostly made of engineering plastics such as PFA (fusible polytetrafluoroethylene), PBT (polybutylene terephthalate), PPS (polyphenylene sulfide), PP (polypropylene), LCP (liquid crystal polymer), and ECM (engineering composite material) to insulate the electrode post 50, which is the positive terminal, from the shell 200, which is the negative terminal.

[0043] However, the aforementioned plastic materials used for insulation have problems such as insufficient melting point and poor heat resistance. When a battery experiences thermal runaway, temperatures can reach over 600 degrees Celsius, causing the plastic materials to melt, burn, or carbonize, rendering them insulated and potentially triggering secondary circuitry issues in parallel-connected cells. Specifically, for example... Figure 1B As shown, during the thermal runaway test of multiple cells in parallel at the packaging level, after the plastic material loses its insulating effect, it triggers a short circuit by causing the positive and negative terminals (terminals and casing) of cell 11 to come into contact. Figure 1B The method involves puncturing cell 13 to simulate a short circuit in cell 11, which in turn causes a short circuit in the parallel cell 12, thus forming a secondary short circuit. Embodiments of this application provide a secondary battery to at least solve this technical problem.

[0044] Figure 2 A perspective view of a secondary battery 100A according to an embodiment of this application is shown. Figure 3 A cross-sectional view of a secondary battery 100A according to an embodiment of this application is shown. For clarity, Figure 3 Some components inside the casing are omitted. Figure 4 It shows Figure 3 A partially enlarged schematic diagram of the terminal side of the secondary battery.

[0045] According to the embodiments of this application, refer to Figures 2 to 4 As shown, the secondary battery 100A may include a housing 200, which may include an end wall 111 and a side wall 112 surrounding the end wall 111. The side wall 112 is connected to the edge of the end wall 111. The end wall 111 and the side wall 112 may define a receiving cavity 105 to receive the electrode assembly 140 of the secondary battery 100A. After the electrode assembly 140 is placed into the receiving cavity 105, the receiving cavity 105 may be closed by a cover plate 220.

[0046] As long as a stable sealing and electrical connection can be formed, the connection between the end wall 111 and the side wall 112 can be achieved in various ways, such as integral stamping, integral casting, or separate welding. The circumference of the side wall 112 is not limited; it can be cylindrical or prismatic, or it can follow any other closed-loop contour that matches the end wall. The receiving cavity 105 formed within the housing 200 can be used to accommodate the electrode assembly 140, electrolyte, current collector, and other necessary battery components. Specifically, the diameter of the housing 200 can be determined according to the specific dimensions of the electrode assembly 140. The housing 200 can be made of various materials, such as copper, iron, aluminum, steel, or aluminum alloy. To prevent rusting during long-term use, a rust-preventive material such as nickel can be plated onto the surface of the housing 200. The secondary battery 100A can be a cylindrical battery, such as a 4680 cylindrical battery with a height of 80mm and an outer diameter of 46mm; or, for example, a battery with a height of 15mm and an outer diameter of 46mm.

[0047] The secondary battery 100A may also include a terminal post 50, which can pass through the end wall 111 and be electrically connected to the electrode assembly 140 via the current collector 145. In some embodiments, the terminal post 50 may be made of aluminum.

[0048] Specifically, the first tab (e.g., negative tab) of the electrode assembly 140 faces the cover plate 220 and can be electrically connected to the housing 200 via a current collector (e.g., negative current collector) located between the cover plate 220 and the electrode assembly 140, thereby giving the housing 200 a first polarity (e.g., negatively charged) and serving as the first terminal (e.g., negative terminal) of the secondary battery 100A. The terminal 50 can be electrically connected to the second tab (e.g., positive tab) of the electrode assembly 140 via a current collector 145 (e.g., positive current collector), thereby giving the terminal 50 a second polarity opposite to the first polarity (e.g., positively charged) and serving as the second terminal (e.g., positive terminal) of the secondary battery 100A.

[0049] See details Figure 4As shown, the end wall 111 may include a terminal hole 118. The terminal hole 118 may be coaxial with the housing 200. The axis Ax of the terminal hole 118 extends along the direction Y, and the direction of the axis Ax of the terminal hole 118 may be referred to as the height direction of the secondary battery. The terminal 50 may specifically include a columnar portion 51, a first flange 52, and a second flange 53. The columnar portion 51 may extend along the direction Y through the terminal hole 118. The first flange 52 and the second flange 53 may be respectively connected to opposite ends of the columnar portion 51 along the direction Y. The first flange 52 and the second flange 53 may each extend beyond the terminal hole 118 in the radial direction X of the terminal hole 118. That is, the projections of the first flange 52 and the second flange 53 in the direction Y both cover the terminal hole 118. The terminal 50 is fixed by clamping the end wall 111 with the first flange 52 and the second flange 53.

[0050] The secondary battery 100A may further include a first plastic component 30, a second plastic component 40, and a sealing ring 70 to insulate the terminal 50 from the housing 200. The first plastic component 30, the second plastic component 40, and the sealing ring 70 may each be annular in shape surrounding the columnar portion 51. The first plastic component 30 is disposed on the side of the end wall 111 facing the outside of the housing. At least a portion of the first plastic component 30 is clamped between the second flange 53 and the end wall 111 to at least isolate the second flange 53 from the end wall 111. The second flange 53 and the end wall 111 together clamp the first plastic component 30. The second plastic component 40 is disposed on the side of the end wall 111 facing the inside of the housing. At least a portion of the second plastic component 40 extends between the first flange 52 and the end wall 111 to at least isolate the first flange 52 from the end wall 111. At least a portion of the sealing ring 70 may be located between the end wall 111 and the second flange 53.

[0051] The secondary battery 100A may further include a heat-resistant insulating component 80. A portion of the heat-resistant insulating component 80 is sandwiched between the first plastic component 30 and the end wall 111. In this embodiment, the first flange 52 located within the housing 200 is an inner flange and is riveted to the end wall 111, meaning the electrode 50 is riveted from the inside of the housing 200. The heat-resistant insulating component 80 is a component independent of the housing 200 and the first plastic component 30. In this embodiment, the heat-resistant insulating component 80 is disposed on the side of the end wall 111 facing the outside of the housing. At least a portion of the heat-resistant insulating component 80 is located between the second flange 53 and the end wall 111. That is, the heat-resistant insulating component 80 is disposed between the non-riveted outer flange (i.e., the second flange 53) of the electrode 50 and the end wall 111. This is because if the heat-resistant insulating component 80 is located between the first flange 52 used for riveting and the end wall 111, the first flange 52 used for riveting will generate pressure on the heat-resistant insulating component 80 during installation, which may easily cause the heat-resistant insulating component 80 to crack.

[0052] In other embodiments, the first flange 52 riveted to the end wall 111 may be an outer flange located outside the housing, and in such embodiments, the heat-resistant insulation 80 may be disposed inside the housing and at least partially located between the end wall 111 and the second flange 53 (which is an inner flange).

[0053] In some embodiments, the material of the first plastic part 30 may be an elastic insulating material, and the first plastic part 30 may also be referred to as an elastic insulating part. In some embodiments, the materials of the first plastic part 30 and the second plastic part 40 may be one of engineering plastics such as PFA, PBT, PPS, PP, LCP, and ECM, respectively. In some embodiments, the materials of the first plastic part 30 and the second plastic part 40 may be the same. The melting point of the heat-resistant insulating part 80 may be higher than that of the first plastic part 30, so that the heat-resistant insulating part 80 is more heat-resistant than the first plastic part 30. The melting point of the heat-resistant insulating part 80 may be greater than 600 degrees Celsius. In some embodiments, the thickness of the heat-resistant insulating part 80 is less than 1 mm. In some embodiments, the hardness of the heat-resistant insulating part 80 may be greater than 800 HV (Vickers hardness unit). In some embodiments, the material of the heat-resistant insulating part may be one of high-temperature resistant materials such as ceramics, mica, and refractory rubber. In some preferred embodiments, the material of the heat-resistant insulating part 80 is ceramic, and the thickness of the ceramic heat-resistant insulating part 80 may be 0.2 mm to 0.6 mm.

[0054] By providing a heat-resistant insulating component 80, which is more heat-resistant than the first plastic component 30, between the non-riveted second flange 53 of the terminal 50 and the end wall 111 of the housing 200, when the battery experiences thermal runaway causing the first plastic component 30 to melt, burn, or carbonize, even after the first plastic component 30 loses its insulating function, the heat-resistant insulating component 80 can still maintain the insulation performance between the terminal 50 and the housing 200, which have different polarities, thereby preventing secondary short circuits in parallel cells. Furthermore, by placing the heat-resistant insulating component 80 between the non-riveted second flange 53 and the housing 200, the riveting pressure can be prevented from causing the heat-resistant insulating component 80 to crack.

[0055] In this embodiment, the first plastic part 30 covers the upper surface of the heat-resistant insulating part 80. Typically, the heat-resistant insulating part 80 is a brittle material; if it directly contacts the rigid second flange 53, it is prone to breakage. By positioning the heat-resistant insulating part 80 between the first plastic part 30 and the end wall 111, with a portion of the first plastic part 30 located between the heat-resistant insulating part 80 and the second flange 53, direct contact between the heat-resistant insulating part 80 and the second flange 53 can be avoided, preventing breakage and protecting the heat-resistant insulating part 80.

[0056] In some embodiments, in the radial direction X of the pole hole 118, the distance L1 between the heat-resistant insulating member 80 and the sealing ring 70 is greater than the distance L2 between the first plastic member 30 and the sealing ring 70. In some embodiments, the inner diameter of the heat-resistant insulating member 80 can be set to be greater than the inner diameter of the first plastic member 30, so that the distance L1 between the heat-resistant insulating member 80 and the sealing ring 70 is greater than the distance L2 between the first plastic member 30 and the sealing ring 70. Typically, a certain gap is left between the first plastic member 30 and the sealing ring 70 to accommodate the extrusion amount of the sealing ring 70 after compression. Setting the distance between the heat-resistant insulating member 80 and the sealing ring 70 to be greater than the distance between the first plastic member 30 and the sealing ring 70 can ensure that there is a sufficient gap between the heat-resistant insulating member 80 and the sealing ring 70 to accommodate the extrusion amount of the sealing ring 70, thereby preventing the extrusion amount of the sealing ring 70 from extruding the heat-resistant insulating member 80.

[0057] In some embodiments, the heat-resistant insulating component 80 and the end wall 111 can be bonded together to fix the heat-resistant insulating component 80 to the end wall 111. Since the heat-resistant insulating component 80 may move during assembly, bonding the heat-resistant insulating component 80 and the end wall 111 can prevent the heat-resistant insulating component 80 from moving during assembly.

[0058] In some embodiments, the thickness of the heat-resistant insulating member 80 is from 0.01 mm to 1.5 mm. In some embodiments, the maximum distance between the second flange 53 and the surface of the end wall 111 facing the outside of the housing is H0. H0 can be used to represent the height of the pole post 50 protruding from the end wall 111. The sum of the thickness of the heat-resistant insulating member 80 in the Y direction and the thickness of the first plastic member 30 is less than H0. Since the added heat-resistant insulating member 80 has a certain thickness, by limiting the sum of the thicknesses of the heat-resistant insulating member 80 and the first plastic member 30 to be less than H0, the requirement for pole post height limitation can be met.

[0059] Figure 5 A partially enlarged schematic diagram of the terminal side of a secondary battery 100B according to another embodiment of this application is shown. Figure 5 Several aspects of the secondary battery 100B shown are similar to those described above for the secondary battery 100A; only the following descriptions are provided. Figure 5 The differences shown are those of the secondary battery 100B. Figure 5In the illustrated embodiment, at least the lower portion of the side 30s of the first plastic part 30 facing away from the axis Ax can be surrounded by a heat-resistant insulating member 80. Specifically, the heat-resistant insulating member 80 includes a first portion 80a and a second portion 80b. The first portion 80a surrounds at least the lower portion of the side 30s of the first plastic part 30, and the second portion 80b is connected to the first portion 80a and located between the first plastic part 30 and the end wall 111. Therefore, the heat-resistant insulating member 80 can limit the position of the first plastic part 30, making assembly easier.

[0060] Figure 6 A cross-sectional view of a secondary battery 100C according to another embodiment of this application is shown. Figure 7 It shows Figure 6 A magnified schematic diagram of a portion of the pole side. Figure 8 It shows Figure 6 A magnified 3D schematic diagram of a portion of the pole side. Combined with... Figures 6 to 8 As shown, in the secondary battery 100C of this embodiment, the side of the heat-resistant insulating component 80 facing away from the axis Ax is covered by the first plastic component 30. Since the heat-resistant insulating component 80 is covered by the first plastic component 30, the heat-resistant insulating component 80 is not exposed. Thus, even if the heat-resistant insulating component 80 breaks, it will not fall out into other spaces inside the casing and affect the battery performance. Furthermore, it can still play an insulating role in the event of high-temperature thermal runaway.

[0061] For details, see Figure 7 and Figure 8 As shown, the first plastic part 30 may include a first portion 301 and a second portion 302. The first portion 301 simultaneously surrounds at least a portion of the outer peripheral surface of the second flange 53 and the outer side of the heat-resistant insulation member 80. The second portion 302 extends from the first portion 301 toward the axis Ax of the pole hole 118. At least a portion of the heat-resistant insulation member 80 is sandwiched between the second portion 302 and the end wall 111. This structural design of the first plastic part 30 allows the outer side of the heat-resistant insulation member 80 to be covered by the first portion 301, and a portion of the upper surface of the heat-resistant insulation member 80 to be covered by the second portion 302. Even if the heat-resistant insulation member 80 breaks, it will not detach, ensuring that it still provides insulation under high-temperature thermal runaway conditions.

[0062] Furthermore, the outer peripheral surface of the second flange 53 facing away from the axis Ax includes a lower sidewall 53a and an upper sidewall 53b, with the lower sidewall 53a being closer to the end wall 111 than the upper sidewall 53b. The lower sidewall 53a is recessed relative to the upper sidewall 53b toward the axis Ax, defining a recessed portion. A second portion 302 of the first plastic member 30 extends into the recess defined by the lower sidewall 53a. By recessing the lower sidewall 53a of the outer peripheral surface of the second flange 53 to form the recessed portion, the second portion 302 of the first plastic member 30 extends and is embedded in the recessed portion, reducing the height of the pole post 50 protruding from the end wall 111. In other words, when the heat-resistant insulating member 80 is provided, the height dimension occupied by the pole post 50 in the Y direction is not increased.

[0063] Along the radial direction X of the pole post hole 118 and in a direction away from the axis Ax, the heat-resistant insulating member 80 may extend beyond the second flange 53, with the outermost edge of the heat-resistant insulating member 80 being further away from the axis Ax than the outermost edge of the second flange 53. In some embodiments, the outer diameter of the heat-resistant insulating member 80 is larger than the outer diameter of the second flange 53, such that the heat-resistant insulating member 80 extends beyond the second flange 53 in the radial direction X. This ensures that in the event of thermal runaway, the second flange 53 can be separated from the end wall 111 at its outermost edge by the heat-resistant insulating member 80, maintaining insulation between the pole post 50 and the end wall 111.

[0064] More specifically, the inner diameter of the heat-resistant insulating component 80 can be smaller than the outer diameter of the second flange 53 at the lower sidewall 53a, that is, the distance b between the lower sidewall 53a of the second flange 53 and the inner surface of the heat-resistant insulating component 80 is greater than 0. This allows a portion of the inner side of the heat-resistant insulating component 80 to extend beyond the lower sidewall 53a of the second flange 53, reaching between the second flange 53 and the end wall 111. This prevents the lower sidewall 53a of the second flange 53 from contacting the end wall 111 during thermal runaway and when the first plastic component 30 is molten, thus maintaining insulation between the pole post 50 and the end wall 111.

[0065] In some embodiments, the absolute value of the difference between the inner diameter and the outer diameter of the heat-resistant insulating member 80 can be greater than the absolute value of the difference between the diameter of the pole hole 118 and the diameter of the columnar portion 51. That is, the width of the heat-resistant insulating member 80 in the radial direction X is greater than the gap between the inner wall of the pole hole 118 and the columnar portion 51 to prevent the heat-resistant insulating member 80 from entering the gap between the pole hole 118 and the columnar portion 51 during assembly. In some embodiments, the inner diameter of the heat-resistant insulating member 80 (e.g., ceramic) can be greater than 15 mm.

[0066] Furthermore, the second portion 302 of the first plastic part 30 may overlap with a portion of the second flange 53 in the Y direction, and the dimension of the overlapping area in the radial direction X is 'a', which in some embodiments may be greater than 0.3 mm. If the dimension 'a' of the overlapping area between the second portion 302 and the second flange 53 is too small, the second portion 302 of the first plastic part 30 may warp or slip out and disengage from the gap between the second flange 53 and the heat-resistant insulating member 80. Therefore, configuring the dimension 'a' of the overlapping area between the second portion 302 and the second flange 53 to be greater than 0.3 mm can prevent the first plastic part 30 from warping or slipping out due to an insufficiently small overlapping area.

[0067] In some embodiments, the thickness of the portion of the second flange 53 that overlaps with the second portion 302 of the first plastic part 30 is d, and d can satisfy d≥0.5mm to ensure the structural strength of the second flange 53.

[0068] In some embodiments, the thickness c of the heat-resistant insulation element 80 along the Y direction can be less than 1 mm, for example, from 0.2 mm to 0.6 mm. The ratio of the thickness c of the heat-resistant insulation element 80 to the thickness of the compressed sealing ring 70 is from 0.25 to 1. This thickness configuration of the heat-resistant insulation element 80 avoids reducing insulation performance due to its thinness, and also avoids occupying excessive height space due to its excessive thickness.

[0069] Figure 9 A cross-sectional view of a secondary battery 100D according to yet another embodiment of this application is shown. (See reference) Figure 9 As shown, the surface of the end wall 111 facing the outside of the housing includes a recess 111r provided around the pole post hole 118. Providing the recess 111r around the pole post hole 118 allows for the installation of the pole post 50 within the hole, reducing the height of the pole post 50. In this embodiment, a heat-resistant insulating member 80 may be disposed in the recess 111r. The sidewall of the recess 111r can restrict the radial movement of the heat-resistant insulating member 80 within the recess 111r. In some embodiments, the outer surface of the heat-resistant insulating member 80 contacts the sidewall of the recess 111r to confine the heat-resistant insulating member 80 within the recess 111r and restrict its radial movement. By providing the heat-resistant insulating member 80 within the recess 111r of the end wall 111, height space can be saved; and by using the recess 111r to limit the heat-resistant insulating member 80, assembly can be facilitated.

[0070] Figure 10 A schematic diagram of an electronic device according to an embodiment of this application is shown. For ease of explanation, the following embodiments use a vehicle as an example to illustrate the electronic device 1000. See also... Figure 10The vehicle has a battery pack 1002 installed inside, which can be located at the bottom, front, or rear of the vehicle body 1001. The battery pack 1002 can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The working part of the electronic device 1000 is electrically connected to the battery pack 1002 to obtain electrical power. The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, but are not limited thereto. The working part is the vehicle body, and the battery pack 1002 is located at the bottom of the vehicle body, providing electrical power for the vehicle's movement or the operation of its internal electrical components. However, in some other embodiments, the electronic device 1000 can also be a mobile phone, portable device, laptop, ship, spacecraft, electric toy, and power tool, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc.; the working part can obtain electrical energy from the battery pack 1002 and perform corresponding functions, such as a fan blade rotation unit or a vacuum cleaner's suction unit. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric boat 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. This application does not impose any special limitations on the aforementioned electronic device 1000.

[0071] Embodiments of this application also provide a battery pack 1002, including any of the secondary batteries 100A-100D described above, and the battery pack 1002 can have the beneficial effects described above regarding the secondary batteries 100A-100D.

[0072] Embodiments of this application also provide an electronic device 1000, including the aforementioned battery pack 1002, and the electronic device 1000 may have the beneficial effects described above regarding the secondary batteries 100A-100D and / or the battery pack 1002.

[0073] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A secondary battery, characterized in that, include: A housing having a first polarity, the housing including an end wall and a side wall surrounding the end wall, the end wall having a pole post hole; The pole has a second polarity opposite to the first polarity. The pole passes through the pole hole and is insulated from the end wall. The pole has a first flange and a second flange respectively provided at opposite ends along the axial direction of the pole hole. The pole clamps the end wall for fixation by the first flange and the second flange, wherein the first flange is riveted to the end wall. A resilient insulating member, at least a portion of which is clamped between the second flange and the end wall; and A heat-resistant insulating component, wherein the melting point of the heat-resistant insulating component is higher than that of the elastic insulating component, and at least a portion of the heat-resistant insulating component is located between the second flange and the end wall and is sandwiched between the elastic insulating component and the end wall.

2. The secondary battery according to claim 1, characterized in that, The second flange is located on the side of the end wall facing the outside of the housing.

3. The secondary battery according to claim 2, characterized in that, The heat-resistant insulating component is bonded to the end wall.

4. The secondary battery according to claim 2, characterized in that, The heat-resistant insulating member includes a first part and a second part, the first part surrounding at least the lower portion of the elastic insulating member on the side opposite to the axis of the pole hole, and the second part being connected to the first part and located between the elastic insulating member and the end wall.

5. The secondary battery according to claim 2, characterized in that, The heat-resistant insulating element extends beyond the second flange along the radial direction of the pole hole and in the axial direction away from the pole hole.

6. The secondary battery according to claim 2, characterized in that, The surface of the end wall facing the outside of the housing includes a recess surrounding the pole hole, in which the heat-resistant insulating member is disposed, and the sidewall of the recess restricts the radial movement of the heat-resistant insulating member within the recess along the pole hole.

7. The secondary battery according to claim 2, characterized in that, The side of the heat-resistant insulating component facing away from the axis of the pole hole is covered by the elastic insulating component.

8. The secondary battery according to claim 7, characterized in that, The elastic insulating member includes a first portion and a second portion, the first portion simultaneously surrounding at least a portion of the outer peripheral surface of the second flange and one side of the heat-resistant insulating member, the second portion extending from the first portion toward the axis of the pole hole, and at least a portion of the heat-resistant insulating member being clamped between the second portion and the end wall.

9. The secondary battery according to claim 8, characterized in that, The outer peripheral surface of the second flange includes a lower sidewall and an upper sidewall, the lower sidewall being closer to the end wall than the upper sidewall, the lower sidewall being recessed relative to the upper sidewall toward the axis of the pole hole to define a recess, and the second portion of the resilient insulator extending into the recess.

10. The secondary battery according to claim 9, characterized in that, The inner diameter of the heat-resistant insulating component is smaller than the outer diameter of the second flange at the lower sidewall.

11. The secondary battery according to claim 8, characterized in that, The second flange overlaps with the second portion of the elastic insulator along the axial direction of the pole hole, and the overlapping area has a radial dimension a greater than 0.3 mm along the pole hole.

12. The secondary battery according to claim 11, characterized in that, The portion of the second flange that overlaps with the second portion has a thickness d along the axial direction, wherein d ≥ 0.5 mm.

13. The secondary battery according to claim 1, characterized in that, The pole post further includes a columnar portion passing through the pole post hole and connecting the first flange and the second flange, wherein the absolute value of the difference between the inner diameter and the outer diameter of the heat-resistant insulating member is greater than the absolute value of the difference between the diameter of the pole post hole and the diameter of the columnar portion.

14. The secondary battery according to claim 1, characterized in that, Also includes: A sealing ring surrounds the columnar portion of the pole that passes through the pole hole, and is located between the second flange and the end wall. Specifically, in the radial direction of the pole hole, the distance between the heat-resistant insulating element and the sealing ring is greater than the distance between the elastic insulating element and the sealing ring.

15. The secondary battery according to claim 14, characterized in that, The heat-resistant insulating component and the sealing ring each have a thickness along the axial direction of the pole hole, wherein the thickness of the heat-resistant insulating component is 0.2 mm to 0.6 mm, and the ratio of the thickness of the heat-resistant insulating component to the thickness of the compressed sealing ring is 0.25 to 1.

16. The secondary battery according to claim 1, characterized in that, The thickness of the heat-resistant insulating component along the axial direction of the pole hole is 0.01 mm to 1.5 mm.

17. The secondary battery according to claim 1, characterized in that, The heat-resistant insulating component is made of one of the following materials: ceramic, mica, or fire-resistant rubber.

18. The secondary battery according to claim 1, characterized in that, The heat-resistant insulating component has a melting point greater than 600 degrees Celsius.

19. The secondary battery according to claim 1, characterized in that, The thickness of the heat-resistant insulating component is less than 1 mm, and the hardness of the heat-resistant insulating component is greater than 800 HV.

20. A battery pack, characterized in that, The secondary battery includes any one of claims 1 to 19.

21. An electronic device, characterized in that, Includes the battery pack as described in claim 20.

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