Insulating sheet for lithium battery and lithium battery

Abstract

The insulating sheet for the lithium battery comprises an insulating washer and a plurality of high-temperature-resistant insulating particles, the insulating washer is used for isolating a positive electrode and a negative electrode of the battery from generating a short circuit, and the plurality of insulating particles are uniformly distributed on the insulating washer. In the embodiment, when the battery is abnormally subjected to high temperature, the positive and negative electrodes of the battery melt the insulating washers due to high temperature, and the plurality of insulating particles can still isolate the positive and negative electrodes of the battery, so that short circuit of the positive and negative electrodes of the battery is avoided, and the use safety of the battery is improved.

Description

Technical Field

[0001] The present application relates to the technical field of lithium batteries, and in particular to an insulating sheet for lithium batteries and a lithium battery. Background Art

[0002] Lithium-ion batteries are secondary batteries (rechargeable batteries) that rely on the movement of lithium ions between the positive and negative electrodes to work. During the charge and discharge process, the positive and negative terminals of the lithium battery must remain insulated to maintain a path with external devices.

[0003] The electrode terminals of lithium batteries generally use insulating sheets to isolate the electrode terminals from other parts of the battery to keep the electrode terminals connected to the positive and negative electrodes of the battery, playing the role of insulation and separation in lithium batteries. However, when the battery is exposed to high temperatures, the positive and negative electrodes of the battery may melt due to the high temperature, thereby causing a short circuit between the positive and negative electrodes. Utility Model Content

[0004] The present application provides an insulating sheet for a lithium battery and a lithium battery, which can reduce the risk of the insulating sheet melting under high temperature conditions and causing a short circuit between the positive and negative electrodes of the battery.

[0005] According to one aspect of the present application, an embodiment provides an insulating sheet for a lithium battery, comprising an insulating gasket and a plurality of high temperature resistant insulating particles, wherein the insulating gasket is used to isolate the positive and negative electrodes of the battery from short circuiting, and the plurality of insulating particles are evenly distributed on the insulating gasket.

[0006] In another embodiment, at least three insulating particles are provided and embedded in the insulating gasket.

[0007] According to another aspect of the present application, an embodiment provides a lithium battery, comprising:

[0008] A shell, wherein a winding core is disposed inside the shell, the shell is electrically conductive with the negative electrode of the winding core and serves as the negative electrode of the battery, and a mounting hole is provided on any end wall of the shell;

[0009] A positive terminal, the positive terminal is inserted into the mounting hole, and the positive terminal is electrically conductive with the core positive electrode and serves as a positive electrode of the battery; and

[0010] An insulating assembly includes an insulating member, a sealing member and the above-mentioned insulating sheet, wherein the insulating member is arranged between the positive electrode of the winding core and the inner wall of the shell, the insulating sheet is arranged between the shell and the positive terminal, the insulating member and the insulating sheet are both used to isolate the positive electrode of the battery from the negative electrode of the battery, and the sealing member is arranged between the positive terminal and the mounting hole, and is used to seal the mounting hole.

[0011] In another embodiment, the positive terminal includes a positioning section, a perforated section and a locking section in sequence, the locking section penetrates into the shell and contacts the core positive electrode for conductivity, the positioning section is arranged on the outside of the shell, and the perforated section is arranged in the mounting hole; and the cross-sectional areas of the positioning section and the locking section are both larger than the cross-sectional area of ​​the mounting hole, so that the positioning section and the locking section are respectively locked on the inner and outer sides of the shell end wall.

[0012] In another embodiment, the cross-section of the positioning section, the perforation section and the locking section along the axis is arranged in an "I" shape.

[0013] In another embodiment, the insulating sheet is provided with two sheets, including an inner insulating gasket and an outer insulating gasket, the inner insulating gasket is arranged between the locking section and the inner wall of the shell, and the outer insulating gasket is arranged between the positioning section and the outer wall of the shell.

[0014] In another embodiment, the seal has an axial cross-section comprising a flush section and a vertical section perpendicular to each other, the flush section being arranged between the positioning section and the outer wall of the shell and fitting against the surface of the shell end wall, and the vertical section being embedded between the perforated section and the inner wall of the mounting hole.

[0015] In another embodiment, a reinforcing gasket is provided on a side of the inner insulating gasket facing away from the inner wall of the shell, and a side of the reinforcing gasket facing away from the inner insulating gasket is supported by the locking section.

[0016] In another embodiment, a pole hole is formed on a side of the positioning section away from the locking section, and a sealing nail is embedded in the pole hole. The sealing nail is used to seal the pole hole so that the positive terminal side is sealed.

[0017] In another embodiment, a current collecting plate conductive to the positive electrode of the winding core is disposed at one end of the winding core close to the mounting hole, and the current collecting plate is used to collect and conduct current.

[0018] According to the insulating sheet and battery of the above-mentioned embodiment, since the high-temperature resistant insulating particles are integrated with the insulating gasket, when the battery is subjected to abnormally high temperature, the positive and negative electrodes of the battery melt the insulating gasket due to the high temperature, and the insulating particles can still isolate the positive and negative electrodes of the battery, avoiding a short circuit between the positive and negative electrodes of the battery, thereby improving the safety of battery use. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is an overall cross-sectional view of an insulating sheet for a lithium battery in one embodiment.

[0020] Figure 2 A cross-sectional view of the overall structure of a lithium battery in one embodiment;

[0021] Figure 3 A top view of a lithium battery in one embodiment;

[0022] Figure 4 for Figure 2 A magnified view of part A;

[0023] Figure 5 is a cross-sectional view of a sealing member in one embodiment;

[0024] Figure numerals: 1. Shell; 11. Mounting hole; 2. Winding core; 21. Current collector; 3. Positive terminal; 31. Positioning section; 32. Punching section; 33. Positioning section; 34. Pole hole; 35. Sealing nail; 4. Insulating assembly; 41. Insulating member; 42. Sealing member; 421. Flush section; 422. Vertical section; 43. Insulating sheet; 431. Inner insulating gasket; 432. Outer insulating gasket; 433. Insulating particles; 5. Reinforcing gasket. DETAILED DESCRIPTION

[0025] The present application is further described in detail below by specific embodiments in conjunction with the accompanying drawings. Wherein similar elements in different embodiments adopt associated similar element numbers. In the following embodiments, many detailed descriptions are intended to enable the present application to be better understood. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, and methods. In some cases, some operations related to the present application are not shown or described in the specification, in order to avoid the core part of the present application being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0026] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various implementations, and the operation steps involved in each embodiment can also be replaced or adjusted in a sequence in a manner that is obvious to those skilled in the art. Therefore, the specification and drawings are only for the purpose of clearly describing a certain embodiment and do not mean that the composition and / or sequence are necessary.

[0027] The serial numbers of the components in this document, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings).

[0028] During the charging and discharging process of a lithium battery, the positive and negative terminals of the lithium battery must remain insulated to maintain a connection with external devices. The electrode terminals of a lithium battery generally use an insulating sheet 43 to isolate the electrode terminals from other positions of the battery to maintain the connection between the electrode terminals and the positive and negative electrodes of the battery, and play the role of insulation and separation in the lithium battery. However, when the battery is exposed to high temperatures, the existing insulating sheet 43 may cause the positive and negative electrodes of the battery to melt due to the high temperature, thereby causing a short circuit between the positive and negative electrodes.

[0029] The present application provides an insulating sheet for a lithium battery and a lithium battery. By embedding a high-temperature resistant insulating solid in an insulating gasket, the risk of melting of the insulating sheet 43 under high temperature conditions and causing a short circuit between the positive and negative electrodes of the battery can be reduced.

[0030] According to one aspect of the present application, an insulating sheet for a lithium battery is provided in one embodiment, please refer to Figure 1 , including an insulating gasket and a plurality of high temperature resistant insulating particles 433, the insulating gasket is used to isolate the positive and negative electrodes of the battery from short circuit, and the plurality of insulating particles 433 are evenly distributed on the insulating gasket; at least three insulating particles 433 are provided and embedded in the insulating gasket.

[0031] In this embodiment, the insulating gasket frame is made of plastic material, and the insulating particles 433 are made of ceramic beads. The insulating ceramic material has high mechanical strength, high thermal conductivity, and wear resistance. It has excellent insulation properties under high temperature and high frequency, stable chemical and physical properties, and the three ceramic beads are evenly distributed, which can maintain structural stability. When the battery is abnormally exposed to high temperature, the positive and negative electrodes of the battery melt the insulating gasket due to the high temperature, and the multiple insulating particles 433 can still isolate the positive and negative electrodes of the battery to avoid short circuit of the positive and negative electrodes of the battery, thereby improving the safety of battery use.

[0032] According to another aspect of the present application, a lithium battery is provided in one embodiment, using the above-mentioned insulating sheet for lithium battery, please refer to Figure 2 and Figure 3 , including a shell 1, a winding core 2, a positive terminal 3 and an insulating component 4, the winding core 2 is installed inside the shell 1, and the shell 1 is conductive with the negative electrode of the winding core 2 and serves as the negative electrode of the battery. In this embodiment, a cylindrical steel shell can be used; a mounting hole 11 is opened on either end wall of the shell 1, and a current collecting plate 21 conductive with the positive electrode of the winding core 2 is provided at one end of the winding core 2 close to the mounting hole 11, and the current collecting plate 21 is used to collect and conduct current; the positive terminal 3 is installed in the mounting hole 11 as the positive electrode of the battery and contacts with the current collecting plate 21 for conduction; the insulating component 4 is used to isolate the positive electrode of the battery from the negative electrode of the battery and seal the mounting hole 11.

[0033] Please refer to Figure 4The positive terminal 3 includes a positioning section 31, a perforated section 32 and a locking section 33 in sequence. The cross-sections of the positioning section 31, the perforated section 32 and the locking section 33 along the axis are arranged in an "I"-shaped rivet; specifically, the locking section 33 penetrates into the shell 1 from the mounting hole 11 and contacts and conducts with the current collecting plate 21, the perforated section 32 is penetrated in the mounting hole 11, and the positioning section 31 is located outside the shell 1; and the cross-sectional areas of the positioning section 31 and the locking section 33 are both larger than the cross-sectional area of ​​the mounting hole 11, so that the positioning section 31 and the locking section 33 are respectively locked on the inner and outer sides of the end wall of the shell 1.

[0034] In this embodiment, please refer to Figure 4 The insulating component 4 is specifically arranged at the contact position between the positive terminal 3 and the shell 1, specifically at: the lower surface of the positioning section 31 and the outer surface of the end wall of the shell 1, the peripheral surface of the perforated section 32 and the hole wall of the mounting hole 11, and the upper surface of the locking section 33 and the inner surface of the end wall of the shell 1. The insulating component 4 is arranged at the corresponding position, and the positive terminal 3 and the shell are isolated by using an insulating material, thereby achieving insulation between the positive and negative electrodes of the battery.

[0035] Please refer to Figure 4 The insulating assembly 4 includes an insulating member 41, a sealing member 42 and an insulating sheet 43. The insulating member 41 is arranged between the current collecting plate 21 and the inner wall of the housing 1, and the insulating sheet 43 is arranged between the housing 1 and the positive terminal 3. The insulating member 41 and the insulating sheet 43 are used to isolate the positive electrode of the battery from the negative electrode of the battery. The sealing member 42 is arranged between the positive terminal 3 and the mounting hole 11 and is used to seal the mounting hole 11. The insulating member 41, the sealing member 42 and the insulating sheet 43 are all coaxially sleeved on the peripheral side of the perforated section 32.

[0036] For details, please refer to Figure 1 and Figure 4 The insulating sheet 43 is provided with two sheets, including an inner insulating gasket 431 and an outer insulating gasket 432. The inner insulating gasket 431 is arranged between the upper surface of the positioning section 33 and the inner wall of the end wall of the housing 1, and the outer insulating gasket 432 is arranged between the lower surface of the positioning section 31 and the outer wall of the end wall of the housing 1, and the outer ring of the outer insulating gasket 432 is arranged beyond the peripheral side of the positioning end. Multiple high temperature resistant insulating particles 433 are arranged on the inner insulating gasket 431 and the outer insulating gasket 432, and the multiple insulating particles 433 are evenly distributed on the insulating gasket; at least three insulating particles 433 are arranged and embedded in the insulating gasket, so that the insulating sheet 43 fits flush with the contact surface.

[0037] In this embodiment, the insulating gasket frame is made of plastic material, the insulating particles 433 are made of ceramic beads, and the three ceramic beads are evenly distributed, which can maintain stability in structure. When the battery is abnormally exposed to high temperature, the positive and negative electrodes of the battery melt the insulating gasket due to the high temperature, and the multiple insulating particles 433 can still isolate the positive and negative electrodes of the battery, avoiding short circuit of the positive and negative electrodes of the battery, thereby improving the safety of battery use. The insulating member 41 can also adopt an insulating sheet 43 structure, or an insulating member 41 made of existing plastic material.

[0038] Please refer to Figure 4 A reinforcing gasket 5 is provided on the side of the inner insulating gasket 431 away from the inner wall of the shell 1. The reinforcing gasket 5 is sleeved on the perforated section 32. The side of the reinforcing gasket 5 away from the inner insulating gasket 431 is supported by the upper surface of the clamping section 33. The reinforcing gasket 5 is used to support the inner insulating gasket 431 to ensure that the riveting force is diffused to most of the surface of the inner insulating ring.

[0039] Please refer to Figure 5 The seal 42 adopts a sealing rubber ring and is arranged at the inner corner of the positioning end and the perforated section 32. Its cross section along the axial direction is symmetrically arranged, and either side includes a flush section 421 and a vertical section 422 that are perpendicular to each other. Specifically, the flush section 421 is flush with the outer insulating gasket 432 and is arranged between the positioning section 31 and the outer wall of the shell 1, and the vertical section 422 is embedded between the perforated section 32 and the inner wall of the mounting hole 11; thereby blocking the gap between the positive terminal 3 and the mounting hole 11 to ensure the sealing of the mounting hole 11.

[0040] Please refer to Figure 4 A pole hole 34 is provided on the side of the positioning section 31 away from the locking section 33. The pole hole 34 is set as a blind hole and is coaxially arranged with the mounting hole 11. The inner diameter of the pole hole 34 is smaller than the inner diameter of the mounting hole 11. A sealing nail 35 is embedded in the pole hole 34. The sealing nail 35 is used to block the pole hole 34 to improve the side sealing ability of the positive terminal 3. At the same time, the end of the busbar of the battery pack connected to the positive terminal 3 can be abutted against the blocking nail, thereby providing positioning for the busbar welding of the battery pack.

[0041] The above specific examples are used to illustrate the present invention, which is only used to help understand the present invention and is not intended to limit the present invention. For technicians in the technical field of the present invention, they can also make some simple deductions, deformations or substitutions based on the idea of ​​the present invention.

Claims

1. An insulating sheet for a lithium battery, characterized in that: It comprises an insulating gasket and a plurality of high temperature resistant insulating particles (433), wherein the insulating gasket is used to isolate the positive and negative electrodes of the battery from short circuit, and the plurality of insulating particles (433) are evenly distributed on the insulating gasket.

2. The insulating sheet for lithium battery according to claim 1, characterized in that: At least three insulating particles (433) are provided and embedded in the insulating gasket.

3. A lithium battery, characterized in that: include: A shell (1), wherein a winding core (2) is arranged inside the shell (1), the shell (1) and the negative electrode of the winding core (2) are electrically conductive and serve as the negative electrode of the battery, and a mounting hole (11) is provided on any end wall of the shell (1); A positive terminal (3), the positive terminal (3) is inserted into the mounting hole (11), and the positive terminal (3) is electrically conductive with the positive electrode of the winding core (2) and serves as a positive electrode of the battery; and An insulating component (4), comprising an insulating member (41), a sealing member (42) and an insulating sheet (43) as claimed in any one of claims 1 to 2, wherein the insulating member (41) is arranged between the positive electrode of the winding core (2) and the inner wall of the shell (1), and the insulating sheet (43) is arranged between the shell (1) and the positive terminal (3), and the insulating member (41) and the insulating sheet (43) are both used to isolate the positive electrode of the battery from the negative electrode of the battery, and the sealing member (42) is arranged between the positive terminal (3) and the mounting hole (11), and is used to seal the mounting hole (11).

4. The lithium battery according to claim 3, characterized in that The positive terminal (3) comprises a positioning section (31), a perforated section (32) and a locking section (33) in sequence; the locking section (33) penetrates into the shell (1) and contacts the positive electrode of the winding core (2) for electrical conduction; the positioning section (31) is arranged outside the shell (1), and the perforated section (32) is arranged inside the mounting hole (11); and the cross-sectional areas of the positioning section (31) and the locking section (33) are both larger than the cross-sectional area of ​​the mounting hole (11), so that the positioning section (31) and the locking section (33) are respectively locked on the inner and outer sides of the end wall of the shell (1).

5. The lithium battery according to claim 4, characterized in that The positioning section (31), the perforating section (32) and the locking section (33) are arranged in an "I" shape along the cross section of the axis.

6. The lithium battery according to claim 4, characterized in that The insulating sheet (43) is provided with two sheets, including an inner insulating gasket (431) and an outer insulating gasket (432); the inner insulating gasket (431) is provided between the locking section (33) and the inner wall of the shell (1); and the outer insulating gasket (432) is provided between the positioning section (31) and the outer wall of the shell (1).

7. The lithium battery according to claim 6, characterized in that The cross section of the sealing member (42) along the axial direction comprises a flush section (421) and a vertical section (422) which are perpendicular to each other, wherein the flush section (421) is arranged between the positioning section (31) and the outer wall of the shell (1) and is in contact with the surface of the end wall of the shell (1), and the vertical section (422) is embedded between the perforated section (32) and the inner wall of the mounting hole (11).

8. The lithium battery according to claim 6, characterized in that A reinforcing gasket (5) is provided on the side of the inner insulating gasket (431) facing away from the inner wall of the shell (1), and the side of the reinforcing gasket (5) facing away from the inner insulating gasket (431) is supported by the locking section (33).

9. The lithium battery according to claim 4, characterized in that: A pole hole (34) is provided on the side of the positioning section (31) facing away from the locking section (33), and a sealing nail (35) is embedded in the pole hole (34). The sealing nail (35) is used to seal the pole hole (34) so ​​that the positive terminal (3) side is sealed.

10. The lithium battery according to claim 3, characterized in that: A current collecting plate (21) electrically conductive with the positive electrode of the winding core (2) is provided at one end of the winding core (2) close to the mounting hole (11), and the current collecting plate (21) is used to collect and conduct current.

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