Battery top cover structure and battery

Abstract

The utility model provides a battery top cover structure and a battery. The battery top cover structure comprises a pole assembly, a lower plastic, a cover plate, a connecting piece and an explosion-proof piece, the lower plastic comprises a high-temperature-resistant blocking piece and a lower plastic body, the lower plastic body is fixedly connected with the high-temperature-resistant blocking piece, the lower plastic body and the high-temperature-resistant blocking piece are both connected to the inner side of the cover plate, and the connecting piece is connected with the explosion-proof piece. The high-temperature-resistant blocking piece and the pressure relief hole are oppositely arranged. When the battery is subjected to thermal runaway, the lower plastic body is fused, and the high-temperature-resistant blocking piece abuts against the cover plate and is arranged opposite to the pressure relief hole, so that the pressure relief hole cannot be directly impacted by high-temperature and high-pressure gas mixed with positive and negative electrode materials and melt, and meanwhile, a battery cell in the shell can be prevented from moving towards the pressure relief hole; therefore, the high-temperature and high-pressure gas can be guided out of the shell in time, and the risk of fire and explosion of the battery cell is reduced.

Description

Technical Field

[0001] The present disclosure relates to the technical field of lithium batteries, and in particular to a battery top cover structure and a battery. Background Art

[0002] Battery thermal runaway refers to the phenomenon that the battery temperature rises rapidly and exceeds the normal operating temperature range due to the runaway internal chemical reaction during the charging or discharging process. This phenomenon may cause the battery to overheat, burn or even explode, causing serious safety problems. The melting point of the existing plastic under the square battery cell is generally between 164℃-170℃. When the melting point is higher than the melting point, the lower plastic structure will melt and deform, and lose its supporting function. When the battery cell is in thermal runaway, the temperature can reach 500℃-600℃. At this time, the lower plastic is completely melted and cannot prevent the battery cell from moving upward. The upward movement of the battery cell blocks the pressure relief hole, and the high-temperature and high-pressure gas mixed with the molten material directly impacts the pressure relief hole, causing the pressure relief hole to be blocked. The amount of gas accumulates to exceed the maximum pressure that the shell can withstand, causing the battery to explode, causing serious safety problems.

[0003] In order to solve the above problems, a Chinese patent with application number CN202120873596.1 discloses a battery top cover and a battery for preventing thermal runaway, including a cover plate and a lower plastic, wherein the cover plate is placed on the lower plastic, and is characterized in that a liquid reservoir is provided on the lower plastic, a thermal runaway slow-release agent is contained in the liquid reservoir, and a hot melt area is provided at the bottom of the liquid reservoir.

[0004] The above-mentioned battery top cover for preventing thermal runaway is provided with a liquid reservoir on the lower plastic, a thermal runaway slow-release agent is contained in the liquid reservoir, and a hot-melt area is provided at the bottom of the liquid reservoir. When the temperature inside the battery cell rises, but has not yet reached the temperature of thermal runaway of the battery cell, the hot-melt area provided at the bottom of the liquid reservoir is triggered to melt, causing the thermal runaway slow-release agent in the liquid reservoir to flow out and be injected into the battery, thereby increasing the impedance or directly blocking the transmission of lithium ions, thus playing the role of breaking the circuit of the entire battery cell, and can also reduce the temperature of the battery cell. However, since the above-mentioned lower plastic needs to have a liquid reservoir and contain a thermal runaway slow-release agent in the liquid reservoir, the process is relatively complicated when assembling the battery, and the thermal runaway slow-release agent will increase the production cost.

[0005] Therefore, a lower plastic structure is needed that can prevent the pressure relief hole from being blocked when the battery is under thermal runaway and has a simpler structure and lower cost. Utility Model Content

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a battery top cover structure and a battery.

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

[0008] A battery top cover structure, comprising a pole assembly, a lower plastic, a cover plate, a connecting piece and an explosion-proof piece, wherein the cover plate is respectively provided with a pressure relief hole and a pole hole, the pole assembly is installed in the pole hole, the lower plastic is clamped and connected between the cover plate and the connecting piece, the connecting piece is connected to the pole assembly, and the explosion-proof piece is installed in the pressure relief hole;

[0009] The lower plastic includes a high temperature resistant barrier and a lower plastic body, the lower plastic body is fixedly connected to the high temperature resistant barrier, the lower plastic body and the high temperature resistant barrier are both connected to the inner side of the cover plate, and the high temperature resistant barrier is arranged opposite to the pressure relief hole.

[0010] In one embodiment, the high temperature resistant barrier and the lower plastic body are an integrally formed structure.

[0011] In one embodiment, the melting point of the high temperature resistant barrier is between 500°C and 600°C, and the melting point of the lower plastic body is between 164°C and 170°C.

[0012] In one embodiment, the pressure relief hole is arranged at the center of the cover plate.

[0013] In one of the embodiments, the lower plastic structure is provided with a buffer groove, and the high temperature resistant barrier is arranged at the bottom of the buffer groove.

[0014] In one embodiment, the buffer groove is disposed at the center of the lower plastic body, and the buffer groove is disposed opposite to the pressure relief hole.

[0015] In one embodiment, the high temperature resistant blocking member includes a blocking portion and a supporting portion which are integrally formed, the supporting portion is connected to the cover plate, and the blocking portion is connected to the lower plastic body.

[0016] In one embodiment, there are two supporting parts, the two supporting parts are arranged opposite to each other, and both of the two supporting parts are connected to the cover plate.

[0017] In one embodiment, the pole assembly includes a pole, an upper plastic and a sealing ring, the sealing ring is located in the pole hole, the sealing ring is clamped and connected to the pole and the cover plate, the pole is connected to the upper plastic, and the pole passes through the pole hole to be connected to the connecting piece.

[0018] A battery comprises the battery top cover structure described in any one of the above embodiments.

[0019] Compared with the prior art, the present invention has at least the following advantages:

[0020] In the battery top cover structure mentioned above, the cover plate is provided with a pressure relief hole, and the explosion-proof plate is installed in the pressure relief hole. When thermal runaway occurs, high-temperature and high-pressure gas is generated in the battery shell, and the high-temperature and high-pressure gas breaks through the explosion-proof plate so that the high-temperature and high-pressure gas can be discharged from the shell through the pressure relief hole. Furthermore, the lower plastic includes a high-temperature resistant barrier and a lower plastic body. When the battery is in thermal runaway, the internal temperature of the battery rises, and the lower plastic body melts. The high-temperature resistant barrier supports the cover plate and is arranged opposite to the pressure relief hole, so that the pressure relief hole will not be directly impacted by the high-temperature and high-pressure gas mixed with positive and negative electrode materials and melts. At the same time, it can also prevent the battery cell in the shell from moving toward the pressure relief hole, ensuring that the pressure relief hole will not be blocked by the melt and the battery cell, and maintaining a smooth state, so that the high-temperature and high-pressure gas can be timely discharged from the shell, and the risk of fire and explosion of the battery cell is reduced. On the other hand, compared with the prior art in which a thermal runaway slow-release agent is provided in the lower plastic, the structure of the present application is simpler and the production cost is lower. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] 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.

[0022] Figure 1 It is a schematic diagram of an exploded structure of a battery top cover structure according to an embodiment;

[0023] Figure 2 for Figure 1 Another structural schematic diagram of the battery top cover structure shown;

[0024] Figure 3 for Figure 1 A schematic diagram of the structure of the lower plastic of the battery top cover structure shown;

[0025] Figure 4 for Figure 1 Schematic diagram of the exploded structure of the pole assembly of the battery top cover structure shown. DETAILED DESCRIPTION

[0026] 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.

[0027] 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.

[0028] 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.

[0029] The present disclosure provides a battery top cover structure, comprising a pole assembly, a lower plastic, a cover plate, a connecting piece and an explosion-proof piece, wherein the cover plate is respectively provided with a pressure relief hole and a pole hole, the pole assembly is installed in the pole hole, the lower plastic is clamped and connected between the cover plate and the connecting piece, the connecting piece is connected to the pole assembly, and the explosion-proof piece is installed in the pressure relief hole; the lower plastic comprises a high-temperature resistant barrier and a lower plastic body, the lower plastic body is fixedly connected to the high-temperature resistant barrier, the lower plastic body and the high-temperature resistant barrier are both connected to the inner side of the cover plate, and the high-temperature resistant barrier is arranged opposite to the pressure relief hole.

[0030] In the battery top cover structure mentioned above, the cover plate is provided with a pressure relief hole, and the explosion-proof plate is installed in the pressure relief hole. When thermal runaway occurs, high-temperature and high-pressure gas is generated in the battery shell, and the high-temperature and high-pressure gas breaks through the explosion-proof plate so that the high-temperature and high-pressure gas can be discharged from the shell through the pressure relief hole. Furthermore, the lower plastic includes a high-temperature resistant barrier and a lower plastic body. When the battery is in thermal runaway, the internal temperature of the battery rises, and the lower plastic body melts. The high-temperature resistant barrier supports the cover plate and is arranged opposite to the pressure relief hole, so that the pressure relief hole will not be directly impacted by the high-temperature and high-pressure gas mixed with positive and negative electrode materials and melts. At the same time, it can also prevent the battery cell in the shell from moving toward the pressure relief hole, ensuring that the pressure relief hole will not be blocked by the melt and the battery cell, and maintaining a smooth state, so that the high-temperature and high-pressure gas can be timely discharged from the shell, and the risk of fire and explosion of the battery cell is reduced. On the other hand, compared with the prior art in which a thermal runaway slow-release agent is provided in the lower plastic, the structure of the present application is simpler and the production cost is lower.

[0031] 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:

[0032] like Figures 1 to 3As shown, a battery top cover structure 10 of an embodiment includes a pole assembly 100, a lower plastic 200, a cover plate 300, a connecting piece 400 and an explosion-proof piece 500. The cover plate 300 is respectively provided with a pressure relief hole 300a and a pole hole 300b. The pole assembly 100 is installed in the pole hole 300b. The lower plastic 200 is clamped and connected between the cover plate 300 and the connecting piece 400. The connecting piece 400 is connected to the pole assembly 100, and the explosion-proof piece 500 is installed in the pressure relief hole 300a.

[0033] Furthermore, the lower plastic 200 includes a high temperature resistant barrier 210 and a lower plastic body 220, the lower plastic body 220 is fixedly connected to the high temperature resistant barrier 210, the lower plastic body 220 and the high temperature resistant barrier 210 are both connected to the inner side of the cover plate 300, the high temperature resistant barrier 210 is arranged opposite to the pressure relief hole 300a, so that the high temperature resistant barrier 210 is arranged below the pressure relief hole 300a.

[0034] In this embodiment, the cover plate 300 is provided with a circular pressure relief hole 300a, and the explosion-proof plate 500 is matched with the pressure relief hole 300a. When thermal runaway occurs, high-temperature and high-pressure gas is generated in the battery shell. Under the action of pressure, the high-temperature and high-pressure gas breaks open the explosion-proof plate 500 installed in the pressure relief hole 300a, so that the high-temperature and high-pressure gas can be discharged from the shell through the pressure relief hole 300a. Furthermore, the lower plastic 200 includes a high temperature resistant barrier 210 with a melting point between 500°C and 600°C and a lower plastic body 220 with a melting point between 164°C and 170°C. When thermal runaway occurs, the temperature can reach 500°C, causing the lower plastic body 220 to melt, while the high temperature resistant barrier 210 will not melt, that is, the high temperature resistant barrier 210 supports the cover plate 300 and is arranged opposite to the pressure relief hole 300a, so that the pressure relief hole 300a will not be directly impacted by the high temperature and high pressure gas mixed with positive and negative electrode materials and melt, and can also prevent the battery cells in the shell from moving toward the pressure relief hole 300a.

[0035] In the battery top cover structure 10, the cover plate 300 is provided with a pressure relief hole 300a, and the explosion-proof plate 500 is installed in the pressure relief hole 300a. When thermal runaway occurs, high-temperature and high-pressure gas is generated in the battery shell, and the high-temperature and high-pressure gas breaks through the explosion-proof plate 500 so that the high-temperature and high-pressure gas can be discharged from the shell through the pressure relief hole 300a. Further, the lower plastic 200 includes a high-temperature resistant barrier 210 and a lower plastic body 220. When the battery thermal runaway occurs, the internal temperature of the battery rises, and the lower plastic body 220 melts, and the high-temperature resistant barrier 210 supports the cover plate 300 and is arranged opposite to the pressure relief hole 300a, so that the pressure relief hole 300a will not be directly impacted by the high-temperature and high-pressure gas mixed with positive and negative electrode materials and melts, and at the same time, it can also prevent the battery cell in the shell from moving to the pressure relief hole 300a, ensuring that the pressure relief hole 300a will not be blocked by the melt and the battery cell, and keep it unobstructed. In this way, the high-temperature and high-pressure gas can be timely discharged from the shell, and the risk of battery cell fire and explosion is reduced. On the other hand, compared with the prior art in which a thermal runaway slow-release agent is provided in plastic, the structure of the present application is simpler and the production cost is lower.

[0036] like Figure 1 As shown, in one embodiment, the high temperature resistant barrier 210 and the lower plastic body 220 are integrally formed. In this embodiment, the lower plastic 200 is a composite structure of the high temperature resistant barrier 210 and the lower plastic body 220, which is integrally molded by injection molding, taking into account both production cost and thermal stability.

[0037] like Figure 1 As shown, in one embodiment, the melting point of the high temperature resistant barrier 210 is between 500° C. and 600° C., and the melting point of the lower plastic body 220 is between 164° C. and 170° C. It can be understood that when thermal runaway occurs in the battery housing, the temperature may reach 500° C., at which time the lower plastic body 220 melts, while the high temperature resistant barrier 210 does not melt.

[0038] like Figure 1 As shown, in one embodiment, the pressure relief hole 300a is arranged at the center of the cover plate 300. It can be understood that the pressure relief hole 300a is arranged at the center of the cover plate 300, so that the high-temperature and high-pressure gas generated by the positive and negative battery cells can be discharged from the pressure relief hole 300a at the same time, ensuring the stability of the gas pressure in the shell.

[0039] like Figure 1As shown, in one embodiment, the lower plastic 200 is provided with a buffer groove 230, and the high temperature resistant barrier 210 is arranged at the bottom of the buffer groove 230. It can be understood that by providing the buffer groove 230 and arranging the high temperature resistant barrier 210 at the bottom of the buffer groove 230, when the battery has thermal runaway, the high temperature and high pressure gas mixed with the positive and negative electrode materials and the melt of the battery will not directly impact the pressure relief hole 300a, and the high temperature and high pressure gas will be blocked by the high temperature resistant barrier 210 and buffered by the buffer groove 230 before being discharged through the pressure relief hole 300a, so as to prevent the pressure relief hole 300a from being blocked by the positive and negative electrode materials and the melt, so that the buffer groove 230 has a buffering effect.

[0040] like Figure 1 As shown, in one embodiment, the buffer groove 230 is arranged at the center of the lower plastic 200, and the buffer groove 230 is arranged opposite to the pressure relief hole 300a. It can be understood that the buffer groove 230 is arranged opposite to the pressure relief hole 300a, that is, the high temperature resistant blocking member 210 is arranged opposite to the pressure relief hole 300a, so that when the lower plastic body 220 melts, the battery cell in the shell is blocked by the high temperature resistant blocking member 210 when moving upward, preventing the battery cell from blocking the pressure relief hole 300a, thereby keeping the pressure relief hole 300a unobstructed, and the high temperature and high pressure gas can be discharged from the pressure relief hole 300a in time.

[0041] like Figure 1 and Figure 3 As shown, in one embodiment, the high temperature resistant blocking member 210 includes an integrally formed blocking portion 211 and a supporting portion 212, the supporting portion 212 is connected to the cover plate 300, and the blocking portion 211 is connected to the lower plastic body 220. It can be understood that the supporting portion 212 is connected to the cover plate 300, the supporting portion 212 is used to connect the cover plate 300 and the high temperature resistant blocking member 210, and plays a supporting role, and the blocking portion 211 is used to block the battery cell from moving upward to prevent the battery cell from blocking the pressure relief hole 300a.

[0042] like Figure 3 As shown, in one embodiment, there are two support parts 212, the two support parts 212 are arranged opposite to each other, and the two support parts 212 are connected to the cover plate 300. It can be understood that by providing two support parts 212 connected to the cover plate 300, the connection strength between the high temperature resistant blocking member 210 and the cover plate 300 is improved. Further, according to different structural requirements, in other embodiments, the number of the support parts 212 can be one or more.

[0043] like Figure 1 and Figure 4As shown, in one embodiment, the pole assembly 100 includes a pole 110, an upper plastic 120 and a sealing ring 130, the sealing ring 130 is located in the pole hole 300b, the sealing ring 130 is clamped and connected to the pole 110 and the cover plate 300, the pole 110 is connected to the upper plastic 120, and the pole 110 passes through the pole hole 300b and is connected to the connecting piece 400. It can be understood that there should be two pole assemblies 100, namely the positive pole assembly and the negative pole assembly. Correspondingly, the cover plate 300 is provided with two pole holes 300b, and the number of connecting plates is also two, namely the positive connecting plate and the negative connecting plate. The structures of the positive pole assembly and the negative pole assembly are the same, that is, both include poles, upper plastic and sealing rings. The positive pole assembly and the negative pole assembly are respectively installed in the two pole holes 300b, the positive pole passes through the pole hole to be connected to the positive connecting plate, and the negative pole passes through the other pole hole to be connected to the negative connecting plate, so that the positive pole and the negative pole are respectively connected to the battery cell.

[0044] Compared with the prior art, the present invention has at least the following advantages:

[0045] In the battery top cover structure 10, the cover plate 300 is provided with a pressure relief hole 300a, and the explosion-proof plate 500 is installed in the pressure relief hole 300a. When thermal runaway occurs, high-temperature and high-pressure gas is generated in the battery shell, and the high-temperature and high-pressure gas breaks through the explosion-proof plate 500 so that the high-temperature and high-pressure gas can be discharged from the shell through the pressure relief hole 300a. Further, the lower plastic 200 includes a high-temperature resistant barrier 210 and a lower plastic body 220. When the battery thermal runaway occurs, the internal temperature of the battery rises, and the lower plastic body 220 melts, and the high-temperature resistant barrier 210 supports the cover plate 300 and is arranged opposite to the pressure relief hole 300a, so that the pressure relief hole 300a will not be directly impacted by the high-temperature and high-pressure gas mixed with positive and negative electrode materials and melts, and at the same time, it can also prevent the battery cell in the shell from moving to the pressure relief hole 300a, ensuring that the pressure relief hole 300a will not be blocked by the melt and the battery cell, and keep it unobstructed. In this way, the high-temperature and high-pressure gas can be timely discharged from the shell, and the risk of battery cell fire and explosion is reduced. On the other hand, compared with the prior art in which a thermal runaway slow-release agent is provided in plastic, the structure of the present application is simpler and the production cost is lower.

[0046] 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 battery top cover structure, comprising a pole assembly, a lower plastic, a cover plate, a connecting piece and an explosion-proof piece, wherein the cover plate is respectively provided with a pressure relief hole and a pole hole, the pole assembly is installed in the pole hole, the lower plastic is clamped and connected between the cover plate and the connecting piece, the connecting piece is connected to the pole assembly, and the explosion-proof piece is installed in the pressure relief hole, characterized in that: The lower plastic includes a high temperature resistant barrier and a lower plastic body, the lower plastic body is fixedly connected to the high temperature resistant barrier, the lower plastic body and the high temperature resistant barrier are both connected to the inner side of the cover plate, and the high temperature resistant barrier is arranged opposite to the pressure relief hole.

2. The battery top cover structure according to claim 1, characterized in that: The high temperature resistant barrier and the lower plastic body are an integrally formed structure.

3. The battery top cover structure according to claim 1, characterized in that: The melting point of the high temperature resistant barrier is between 500°C and 600°C, and the melting point of the lower plastic body is between 164°C and 170°C.

4. The battery top cover structure according to claim 1, characterized in that: The pressure relief hole is arranged at the center of the cover plate.

5. The battery top cover structure according to claim 4, characterized in that: The lower plastic body is provided with a buffer groove, and the high temperature resistant blocking member is arranged at the bottom of the buffer groove.

6. The battery top cover structure according to claim 5, characterized in that: The buffer groove is arranged at the center of the lower plastic body, and the buffer groove is arranged opposite to the pressure relief hole.

7. The battery top cover structure according to claim 1, characterized in that: The high temperature resistant blocking member comprises a blocking portion and a supporting portion which are integrally formed, the supporting portion is connected to the cover plate, and the blocking portion is connected to the lower plastic body.

8. The battery top cover structure according to claim 7, characterized in that: There are two support parts, the two support parts are arranged opposite to each other, and both of the two support parts are connected to the cover plate.

9. The battery top cover structure according to claim 1, characterized in that: The pole assembly includes a pole, an upper plastic and a sealing ring, wherein the sealing ring is located in the pole hole, the sealing ring is clamped and connected to the pole and the cover plate, the pole is connected to the upper plastic, and the pole passes through the pole hole and is connected to the connecting piece.

10. A battery, characterized in that: A battery top cover structure comprising any one of claims 1 to 9.

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