Cylindrical battery and battery module

Abstract

The utility model provides a cylindrical battery and a battery module. The cylindrical battery comprises a shell, a top cover assembly, a roll core, an anti-explosion valve assembly and a first PTC part, the shell is covered with the top cover assembly, the anti-explosion valve assembly is connected with the top cover assembly, the roll core is located in the shell, and the first PTC part is clamped and connected between the top cover assembly and the anti-explosion valve assembly; the roll core is provided with a positive pole lug and a negative pole lug, the positive pole lug is electrically connected with the anti-explosion valve assembly, the negative pole lug comprises a negative pole lug body and a second PTC part, the negative pole lug body is connected with the second PTC part, and the negative pole lug body is connected to the shell. Through joint cooperation of the first PTC part and the second PTC part, when the battery is abnormal, the accuracy of current blocking of the first PTC part and the second PTC part is higher, and then the safety performance of the battery is better.

Description

Technical Field

[0001] The present disclosure relates to the field of battery technology, and in particular to a cylindrical battery and a battery module. Background Art

[0002] Batteries are energy supply components for various existing electronic products or electric vehicles. As society develops towards clean energy, lithium batteries with advantages such as high energy ratio and ultra-long service life are popular among the public. However, when the built-in safety protection circuit of the battery fails, or when it is exposed to heat, puncture, extrusion, and impact, high temperature will be generated inside the lithium battery, accompanied by a large amount of gas, which will affect the safety performance of electronic products or electric vehicles. Therefore, the safety performance of the battery is also an issue that needs to be considered in the design of the battery structure.

[0003] In order to solve the above-mentioned safety performance problems, a Chinese patent with application number CN201520459313.3 discloses a PTC cap with an edge, including a top cover, a PTC, an explosion-proof disc, a connecting plate and a sealing ring. The top cover, PTC, explosion-proof disc and connecting plate are arranged in sequence from top to bottom in the sealing ring. A first isolation ring is provided between the explosion-proof disc and the connecting plate. The explosion-proof disc is provided with an edge in the direction of the top cover. The edges of the top cover and the PTC are placed in the edge. A second isolation ring is also provided between the contact surface of the top cover and the edge. The top cover, PTC, explosion-proof disc and the second isolation ring are tightly crimped together by the edge.

[0004] The above battery has a PTC (thermistor) in the cap. When a large current passes through, the PTC thermistor is activated, the internal resistance increases, and then plays a role in blocking the current. However, since the PTC is set in the cap, that is, the PTC is far away from the inside of the battery cell, the cap is close to the external temperature, and there is a large difference between the heat at the cap and the heat generated inside the battery cell, resulting in the PTC being unable to accurately determine whether to block the current.

[0005] Therefore, there is an urgent need for a battery with higher blocking current accuracy and better safety performance. Utility Model Content

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a cylindrical battery and a battery module with high blocking current accuracy and good safety performance.

[0007] The purpose of this disclosure is achieved through the following technical solutions:

[0008] A cylindrical battery, comprising:

[0009] A shell, a top cover assembly, a winding core, an explosion-proof valve assembly and a first PTC component, wherein the top cover assembly is covered on the shell, the explosion-proof valve assembly is connected to the top cover assembly, the winding core is located in the shell, and the first PTC component is clamped and connected between the top cover assembly and the explosion-proof valve assembly;

[0010] The winding core is provided with a positive pole tab and a negative pole tab, the positive pole tab is electrically connected to the explosion-proof valve assembly, the negative pole tab includes a negative pole tab body and a second PTC component, the negative pole tab body is connected to the second PTC component, and the negative pole tab body is connected to the shell.

[0011] In one embodiment, the second PTC component is connected to the head, tail or middle of the negative electrode tab body.

[0012] In one embodiment, the first PTC component is in the shape of a long strip.

[0013] In one embodiment, the second PTC component is in the shape of a long strip.

[0014] In one embodiment, the winding core includes the positive electrode sheet, the negative electrode sheet and the separator, the separator is clamped and abutted between the positive electrode sheet and the negative electrode sheet, the positive electrode sheet, the separator and the negative electrode sheet are wound to form the winding core, the negative electrode tab is connected to the negative electrode sheet, and the positive electrode tab is connected to the positive electrode sheet.

[0015] In one embodiment, the top cover assembly includes a top cover and an insulating seal, the insulating seal is clamped and connected between the top cover and the shell, and the top cover is connected to the first PTC component.

[0016] In one embodiment, the explosion-proof valve assembly includes a pressure relief plate and a flip plate connected to each other, the flip plate is connected to the first PTC component, and the positive electrode tab is connected to the pressure relief plate.

[0017] In one of the embodiments, the positive electrode tab includes a positive electrode tab body and a third PTC component connected to each other, and two ends of the positive electrode tab body are respectively connected to the winding core and the pressure relief sheet.

[0018] In one of the embodiments, the top cover is provided with a pressure relief hole.

[0019] A battery module comprises the cylindrical battery described in any one of the above embodiments.

[0020] Compared with the prior art, the present invention has at least the following advantages:

[0021] In the above-mentioned cylindrical battery, the first PTC component is clamped and connected between the top cover assembly and the explosion-proof valve assembly, that is, the first PTC component is arranged adjacent to the top cover assembly, and the second PTC component is connected to the negative pole tab body, and the negative pole tab body is connected to the winding core, that is, the second PTC component is arranged adjacent to the winding core. Compared with the traditional battery PTC sheet being arranged on the top cover, the present invention discloses that the first PTC component and the second PTC component cooperate with each other, so that when an abnormality occurs in the battery, the first PTC component and the second PTC component have a higher accuracy in blocking the current, thereby improving the safety performance of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present disclosure and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 This is a schematic structural diagram of a cylindrical battery according to an embodiment;

[0024] Figure 2 for Figure 1 The partial enlarged schematic diagram of the cylindrical battery at A shown;

[0025] Figure 3 for Figure 1 A schematic diagram of the structure of the negative electrode tab of the cylindrical battery shown;

[0026] Figure 4 for Figure 1 Schematic diagram of the structure of the positive electrode ear of the cylindrical battery shown. DETAILED DESCRIPTION

[0027] In order to facilitate the understanding of the present disclosure, the present disclosure will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present disclosure are given in the drawings. However, the present disclosure can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present disclosure more thoroughly and comprehensively understood.

[0028] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method.

[0029] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present disclosure. The terms used herein in the specification of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0030] The present disclosure provides a cylindrical battery, comprising a shell, a top cover assembly, a winding core, an explosion-proof valve assembly and a first PTC component, wherein the top cover assembly is covered on the shell, the explosion-proof valve assembly is connected to the top cover assembly, the winding core is located in the shell, and the first PTC component is clamped and connected between the top cover assembly and the explosion-proof valve assembly; the winding core is provided with a positive pole tab and a negative pole tab, the positive pole tab is connected to the explosion-proof valve assembly, the negative pole tab comprises a negative pole tab body and a second PTC component, the negative pole tab body is connected to the second PTC component, and the negative pole tab body is connected to the shell.

[0031] In the above-mentioned cylindrical battery, the first PTC component is clamped and connected between the top cover assembly and the explosion-proof valve assembly, that is, the first PTC component is arranged adjacent to the top cover assembly, and the second PTC component is connected to the negative pole tab body, and the negative pole tab body is connected to the winding core, that is, the second PTC component is arranged adjacent to the winding core. Compared with the traditional battery PTC sheet being arranged on the top cover, the present invention discloses that the first PTC component and the second PTC component cooperate with each other, so that when an abnormality occurs in the battery, the first PTC component and the second PTC component have a higher accuracy in blocking the current, thereby improving the safety performance of the battery.

[0032] In order to better understand the technical solutions and beneficial effects of the present invention, the present invention is further described in detail below in conjunction with specific embodiments:

[0033] like Figures 1 to 4 As shown, a cylindrical battery 10 of an embodiment includes a shell 100, a top cover assembly 200, a winding core 300, an explosion-proof valve assembly 400 and a first PTC component 500, wherein the top cover assembly 200 is covered on the shell 100, that is, the top cover assembly 200 is fixedly connected to the top of the shell 100, the explosion-proof valve assembly 400 is connected to the top cover assembly 200, the winding core 300 is located in the shell 100, and the first PTC component 500 is clamped and connected between the top cover assembly 200 and the explosion-proof valve assembly 400. Furthermore, the winding core 300 is provided with a positive pole tab 310 and a negative pole tab 320 , the positive pole tab 310 is electrically connected to the explosion-proof valve assembly 400 , the negative pole tab 320 includes a negative pole tab body 321 and a second PTC component 322 , the negative pole tab body 321 is connected to the second PTC component 322 , and the negative pole tab body 321 is connected to the shell 100 .

[0034] In this embodiment, the positive pole tab 310 and the negative pole tab 320 are respectively arranged at the two ends of the winding core 300, the negative pole tab 320 is arranged at the bottom of the winding core 300, and the positive pole tab 310 is arranged adjacent to the top cover assembly 200, that is, the current at the positive pole tab 310 can be blocked by the first PTC component 500. The second PTC component 322 is connected to the negative pole tab body 321, and the negative pole tab body 321 is connected to the winding core 300, so that the second PTC component 322 is arranged adjacent to the winding core 300. When an abnormality occurs inside the battery and the temperature rises, the internal resistance of the second PTC component 322 increases, so that the current is blocked and the heat generation is reduced. Further, the first PTC component 500 is arranged adjacent to the top cover assembly 200, and the first PTC component 500 and the second PTC component 322 cooperate with each other, so that the accuracy of blocking the current is higher, and the safety performance of the battery is improved. Further, the first PTC component 500 and the second PTC component 322 are both thermistors.

[0035] In other embodiments, the positive electrode tab 310 may be fixed to the explosion-proof valve assembly 400 by welding, and the negative electrode tab body 321 may be fixed to the housing 100 by welding.

[0036] In the above-mentioned cylindrical battery 10, the first PTC component 500 is clamped and connected between the top cover assembly 200 and the explosion-proof valve assembly 400, that is, the first PTC component 500 is arranged adjacent to the top cover assembly 200, and the second PTC component 322 is connected to the negative pole tab body 321, and the negative pole tab body 321 is connected to the winding core 300, that is, the second PTC component 322 is arranged adjacent to the winding core 300. Compared with the traditional battery PTC sheet being arranged on the top cover 210, the present disclosure cooperates with the first PTC component 500 and the second PTC component 322, so that when an abnormality occurs in the battery, the first PTC component 500 and the second PTC component 322 have a higher accuracy in blocking the current, thereby improving the safety performance of the battery.

[0037] In one embodiment, the second PTC component 322 is connected to the head, tail or middle of the negative pole tab body 321. It can be understood that the head, middle and tail of the negative pole tab body 321 are connected in sequence, the head of the negative pole tab body 321 is connected to the negative pole piece, and the tail of the negative pole tab body 321 is connected to the shell 100. The second PTC component 322 can be welded to the head, tail or middle of the negative pole tab body 321, that is, the second PTC component 322 can be arbitrarily set on the negative pole tab body 321 according to actual needs. In this embodiment, the second PTC component 322 is welded to the tail of the negative pole tab body 321.

[0038] like Figure 2As shown, in one embodiment, the first PTC component 500 is in a strip shape. Of course, in other embodiments, the first PTC component 500 can also be in other shapes such as a square.

[0039] like Figure 3 As shown, in one embodiment, the second PTC component 322 is in a strip shape. Of course, in other embodiments, the second PTC component 322 can also be in other shapes such as a square.

[0040] In one embodiment, the winding core 300 includes the positive electrode sheet, the negative electrode sheet and the separator, the separator is clamped and abutted between the positive electrode sheet and the negative electrode sheet, the positive electrode sheet, the separator and the negative electrode sheet are wound to form the winding core 300, the negative electrode tab 320 is connected to the negative electrode sheet, and the positive electrode tab 310 is connected to the positive electrode sheet.

[0041] In this embodiment, the positive electrode tab 310 is respectively connected to the positive electrode plate and the explosion-proof valve assembly 400, the negative electrode tab 320 is respectively connected to the negative electrode plate and the shell 100, and the first PTC component 500 is arranged on the negative electrode tab body 321. When the internal temperature of the battery rises abnormally, the internal resistance of the first PTC increases, so that the current flowing from the negative electrode plate to the negative electrode tab 320 is blocked.

[0042] like Figure 2 As shown, in one embodiment, the top cover assembly 200 includes a top cover 210 and an insulating seal 220 , the insulating seal 220 is clamped and connected between the top cover 210 and the housing 100 , and the top cover 210 is connected to the first PTC component 500 .

[0043] It can be understood that the insulating seal 220 is connected to the top cover 210 and the housing 100 respectively, so that the top cover 210 and the housing 100 are insulated and have good sealing performance. Further, the insulating seal 220 can be fixed to the top cover 210 and the housing 100 respectively by laser welding or ultrasonic welding. In this embodiment, the insulating seal 220 is a sealing ring.

[0044] like Figure 2 As shown, in one embodiment, the explosion-proof valve assembly 400 includes a pressure relief sheet 410 and a flip sheet 420 connected to each other, the flip sheet 420 is connected to the first PTC component 500 , and the positive electrode tab 310 is connected to the pressure relief sheet 410 .

[0045] It can be understood that a welding point is provided between the pressure relief sheet 410 and the flip sheet 420. When a large amount of gas is generated inside the battery abnormally, the welding point falls off and the flip sheet 420 flips to short-circuit the battery. At the same time, the gas inside the battery is discharged through the flip sheet 420 to achieve the effect of exhaust and pressure relief.

[0046] like Figure 4 As shown, in one embodiment, the positive electrode tab 310 includes a positive electrode tab body 311 and a third PTC component 312 connected to each other, and two ends of the positive electrode tab body 311 are respectively connected to the winding core 300 and the pressure relief sheet 410 .

[0047] It can be understood that by welding the third PTC component 312 on the positive electrode tab body 311, that is, when the temperature on the positive electrode tab 310 increases, the internal resistance of the third PTC component 312 increases to block the current interruption at the positive electrode tab 310, thereby further improving the accuracy of the battery blocking current. In this embodiment, the third PTC component 312 is a thermistor.

[0048] In one embodiment, the top cover 210 is provided with a pressure relief hole. It is understood that when a large amount of gas is abnormally generated inside the battery, the flip sheet 420 flips over to short-circuit the battery to prevent the battery from continuing to heat up, and the gas passes through the flip sheet 420 and then is discharged through the pressure relief hole to prevent the battery from exploding due to excessive gas pressure inside the battery.

[0049] The present application also provides a battery module, comprising the cylindrical battery 10 described in any of the above embodiments.

[0050] Compared with the prior art, the present invention has at least the following advantages:

[0051] In the above-mentioned cylindrical battery 10, the first PTC component 500 is clamped and connected between the top cover assembly 200 and the explosion-proof valve assembly 400, that is, the first PTC component 500 is arranged adjacent to the top cover assembly 200, and the second PTC component 322 is connected to the negative pole tab body 321, and the negative pole tab body 321 is connected to the winding core 300, that is, the second PTC component 322 is arranged adjacent to the winding core 300. Compared with the traditional battery PTC sheet being arranged on the top cover 210, the present disclosure cooperates with the first PTC component 500 and the second PTC component 322, so that when an abnormality occurs in the battery, the first PTC component 500 and the second PTC component 322 have a higher accuracy in blocking the current, thereby improving the safety performance of the battery.

[0052] The above-mentioned embodiments only express several implementation methods of the present disclosure, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the utility model patent. It should be pointed out that, for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the present disclosure, and these all belong to the protection scope of the present disclosure. Therefore, the protection scope of the patent of the present disclosure shall be based on the attached claims.

Claims

1. A cylindrical battery, comprising a shell, a top cover assembly, a winding core, an explosion-proof valve assembly and a first PTC component, wherein the top cover assembly is covered on the shell, the explosion-proof valve assembly is connected to the top cover assembly, the winding core is located in the shell, and the first PTC component is clamped and connected between the top cover assembly and the explosion-proof valve assembly, characterized in that: The winding core is provided with a positive pole tab and a negative pole tab, the positive pole tab is electrically connected to the explosion-proof valve assembly, the negative pole tab includes a negative pole tab body and a second PTC component, the negative pole tab body is connected to the second PTC component, and the negative pole tab body is connected to the shell.

2. The cylindrical battery according to claim 1, characterized in that: The second PTC component is connected to the head, tail or middle of the negative electrode tab body.

3. The cylindrical battery according to claim 1, characterized in that: The first PTC component is in a long strip shape.

4. The cylindrical battery according to claim 1, characterized in that: The second PTC component is in a long strip shape.

5. The cylindrical battery according to claim 1, characterized in that: The winding core includes a positive electrode sheet, a negative electrode sheet and a separator, the separator is clamped and abutted between the positive electrode sheet and the negative electrode sheet, the positive electrode sheet, the separator and the negative electrode sheet are wound to form the winding core, the negative electrode tab is connected to the negative electrode sheet, and the positive electrode tab is connected to the positive electrode sheet.

6. The cylindrical battery according to claim 1, characterized in that: The top cover assembly includes a top cover and an insulating seal. The insulating seal is clamped and connected between the top cover and the shell. The top cover is connected to the first PTC component.

7. The cylindrical battery according to claim 1, characterized in that: The explosion-proof valve assembly includes a pressure relief sheet and a reversing sheet connected to each other. The reversing sheet is connected to the first PTC component, and the positive electrode tab is connected to the pressure relief sheet.

8. The cylindrical battery according to claim 7, characterized in that: The positive electrode tab includes a positive electrode tab body and a third PTC component connected to each other, and two ends of the positive electrode tab body are respectively connected to the winding core and the pressure relief sheet.

9. The cylindrical battery according to claim 1, characterized in that: The top cover is provided with a pressure relief hole.

10. A battery module, characterized in that: A cylindrical battery comprising any one of claims 1 to 9.

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