Battery top cover plate and battery module using same

Abstract

The utility model relates to the technical field of batteries, in particular to a battery top cover plate and a battery module using the battery top cover plate. The exhaust hole group comprises at least one air hole which is formed in the cover plate body and is suitable for penetrating air inside and outside the cover plate body; and the anti-explosion sheet group comprises at least one anti-explosion sheet which is arranged on the side wall of the cover plate body and is suitable for being broken through by gas on the inner side of the cover plate body. According to the utility model, the safety of the whole battery module in the using process can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to a battery top cover plate and a battery module using the battery top cover plate. Background Art

[0002] Lithium batteries are a type of battery that uses lithium metal or lithium alloy as positive / negative electrode materials and non-aqueous electrolyte solutions. Due to the highly active chemical properties of lithium metal, the processing, storage, and use of lithium metal have very high environmental requirements. According to different needs, lithium batteries come in different sizes, models, and shapes. Generally, large lithium batteries are mostly rectangular.

[0003] Large lithium batteries also generate a lot of heat during use. When the heat is too high, there is a risk of explosion. Therefore, in lithium-ion batteries, pressure relief and explosion-proof design are essential. In the prior art, the purpose of pressure relief and explosion-proof is achieved by setting an explosion-proof valve in the cover of the battery; when the internal pressure of the battery is too high, the explosion-proof valve opens to discharge the gas, preventing the battery from exploding and threatening life safety.

[0004] However, actual research has found that relying solely on explosion-proof valves can only cause the battery to explode after the pressure inside the battery increases to a threshold. The time it takes to operate depends on the duration of action of the gas-assisted agent inside the battery, which is highly uncertain. In addition, the explosion-proof valve cannot operate in time for problems such as the external environment becoming hot, and can only wait for the internal air pressure to increase before exploding. In addition, the process of exploding after the internal air pressure of the battery increases to a threshold is inherently dangerous.

[0005] In this regard, for batteries that rely solely on explosion-proof valves to achieve explosion-proofness, their overall structure needs to be further optimized in terms of their safety of use. Utility Model Content

[0006] The first purpose of the utility model is to provide a battery top cover plate to solve the technical problem of optimizing its overall performance.

[0007] The second purpose of the utility model is to provide a battery module to solve the technical problem of improving the safety of its use.

[0008] The battery top cover of the utility model is realized as follows:

[0009] A battery top cover plate, comprising:

[0010] Cover plate body;

[0011] An exhaust hole group, comprising at least one air hole provided on the cover plate body and suitable for passing the air inside and outside the cover plate body; and

[0012] The explosion-proof disk group comprises at least one explosion-proof disk arranged on the side wall of the cover plate body and suitable for being ruptured by the gas inside the cover plate body.

[0013] In an optional implementation of the utility model, a through hole is formed on the cover body and matches one-to-one with at least one explosion-proof disc;

[0014] The through hole passes through the inside and outside of the cover plate body, and the explosion-proof sheet is suitable for covering the corresponding through hole;

[0015] When the explosion-proof plate is broken by the gas inside the cover plate body, the explosion-proof plate releases the covering of the through hole, making the through hole conductive.

[0016] In an optional implementation of the utility model, the explosion-proof disk is integrally formed with the side wall of the cover body; and

[0017] The thickness of the explosion-proof disk is smaller than the depth of the through hole.

[0018] In an optional implementation of the present invention, the explosion-proof plate is welded, bonded or hot-pressed on the cover plate body.

[0019] In an optional implementation of the present invention, the explosion-proof sheet is arranged on the top side wall of the cover body.

[0020] In an optional implementation of the present invention, the exhaust hole group is arranged on the top side wall of the cover body.

[0021] In an optional implementation of the present invention, a concave strip-shaped groove is formed on the outer top end surface of the cover body; and

[0022] The exhaust hole group at least includes an exhaust hole arranged on a side groove wall of the strip-shaped groove along the thickness direction of the cover plate body.

[0023] In an optional implementation of the utility model, the number of air holes located on the same side groove wall of the strip groove along the thickness direction of the cover plate body is not less than two;

[0024] Each of the pores is waist-shaped; and

[0025] Assuming that the major axis of the pore is L1, and the distance between adjacent pores is L2, then

[0026] L1≤L2.

[0027] The battery module of the utility model is realized as follows:

[0028] A battery module, comprising:

[0029] A battery top cover plate, wherein the battery top cover plate adopts the battery top cover plate described above;

[0030] Base;

[0031] A battery cell, wherein the battery cell is arranged between the battery top cover plate and the base; and

[0032] The explosion-proof valve assembly comprises at least one explosion-proof valve arranged on the battery core and used for one-to-one cooperation with at least one explosion-proof disc.

[0033] In an optional implementation of the present invention, the battery module further includes a gas detection component for detecting the concentration of gas exhausted through the exhaust hole group.

[0034] By adopting the above technical solution, the utility model has the following beneficial effects: the battery top cover plate of the utility model and the battery module using the battery top cover plate achieve the purpose of pressure relief and explosion prevention through the explosion-proof plate group provided on the battery top cover plate; when the gas pressure inside the battery is too high, the explosion-proof valve opens to discharge the gas, preventing the battery from exploding and other situations that threaten human safety. In addition, the exhaust hole group provided on the cover body can also be used to discharge the gas generated by the battery failure when the battery fails and generates gas, but before the pressure inside the battery increases to the threshold corresponding to the explosion of the explosion-proof valve, and the gas detection component detects it, so as to timely identify the battery status, improve the safety of the use status, and reduce safety hazards. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 The figure shows a schematic diagram of the structure of the battery top cover plate of the utility model from a first perspective;

[0036] Figure 2 The figure is a second perspective structural schematic diagram of the battery top cover plate of the utility model;

[0037] Figure 3 for Figure 2 A magnified view of part A;

[0038] Figure 4 for Figure 2 B-direction cross-sectional view;

[0039] Figure 5 for Figure 4 Enlarged view of part C;

[0040] Figure 6 The figure shows a schematic structural diagram of the battery top cover plate of the utility model from a third viewing angle;

[0041] Figure 7 for Figure 6 A cross-sectional view of part E;

[0042] Figure 8 for Figure 7 A magnified view of the D portion;

[0043] Fig. 9 Shown is a schematic diagram of the dimensions of an explosion-proof valve on a battery cell of a battery module of the present invention;

[0044] Fig.10 Shown is a schematic structural diagram of a battery module of the present utility model.

[0045] In the figure: cover body 1, explosion-proof plate 2, central part 21, edge 22, air hole 3, strip groove 11, side groove wall 111, through hole 4, explosion-proof valve 5, base 6, battery cell 7. DETAILED DESCRIPTION

[0046] In order to make the content of the utility model more clearly understood, the utility model is further described in detail below based on specific embodiments and in conjunction with the accompanying drawings.

[0047] Example 1: Please refer to Figures 1 to 8 As shown, this embodiment provides a battery top cover plate, comprising: a cover plate body 1 and a venting hole group and an explosion-proof group arranged on the cover plate body 1. As for the cover plate body 1, the whole is roughly rectangular.

[0048] Next, let’s talk about the explosion-proof group:

[0049] Generally, it includes at least one explosion-proof plate 2 arranged on the side wall of the cover body 1 and suitable for being ruptured by the gas inside the cover body 1. It should be noted here that, in this embodiment, the inside of the cover body 1 refers to the side facing the battery cell 7 when the battery top cover is used in a battery module with the battery cell 7, and the outside of the cover body 1 refers to the side facing away from the battery cell 7.

[0050] This embodiment, in conjunction with the accompanying drawings, exemplifies an optional implementation case, in which the explosion-proof group includes two rows of explosion-proof pieces 2 spaced apart, and each row of explosion-proof pieces 2 includes more than two explosion-proof pieces 2. Here, in conjunction with the situation of batteries of different sizes, the number of explosion-proof pieces 2 required to be used is not exactly the same. Therefore, this embodiment does not make an absolute limitation on the specific number of explosion-proof pieces 2.

[0051] Based on the above situation, further speaking, in a more preferred implementation, the explosion-proof piece 2 is arranged on the top side wall of the cover body 1. In this case, a large number of explosion-proof pieces 2 can be arranged, and the area of ​​each explosion-proof piece 2 can also be designed to be relatively large, thereby effectively ensuring the pressure relief and explosion-proof effect of the battery.

[0052] In more detail, each explosion-proof disk 2 of this embodiment has a specific structure as follows:

[0053] A through hole 4 is formed on the cover body 1, which matches at least one explosion-proof sheet 2 one-to-one, that is, there are as many through holes 4 as there are explosion-proof sheets 2. The through hole 4 runs through the inside and outside of the cover body 1, and during the normal use of the battery, the explosion-proof sheet 2 is suitable for covering the corresponding through hole 4; and when the explosion-proof sheet 2 is broken by the gas inside the cover body 1, the explosion-proof sheet 2 releases the cover of the through hole 4, making the through hole 4 conductive, thereby achieving the pressure relief effect of the high-pressure gas inside the cover body 1. The shapes of the through hole 4 and the explosion-proof sheet 2 here are not absolutely limited in this embodiment, and they can be regular shapes or irregular shapes.

[0054] On the basis of the above structure, in an optional and conveniently processed implementation, the explosion-proof disc 2 is integrally formed with the side wall of the cover body 1; and the thickness of the explosion-proof disc 2 is less than the depth of the through hole 4. In this structure, since the through hole 4 passes through the inside and outside of the cover body 1, it can be understood that the explosion-proof disc 2 and the cover body 1 are integrally formed with the same material, and the explosion-proof disc 2 is only formed to be relatively thin relative to the cover body 1.

[0055] In addition to the above optional implementations, the explosion-proof disc 2 of this embodiment can also be formed on the cover plate body 1 by welding, bonding or hot pressing.

[0056] Next, the exhaust hole group generally includes at least one air hole 3 provided on the cover body 1 and adapted to pass the air inside and outside the cover body 1. The shape of the air hole 3 is not absolutely limited in this embodiment, and it can be a regular shape or an irregular shape.

[0057] More specifically, in an optional implementation, the exhaust hole group is arranged on the top side wall of the cover body 1. The exhaust hole group here can be understood as being similar to the position of the explosion-proof disk group. Since the air holes 3 of the exhaust hole group in this case are directly arranged on the top side wall, considering that dust and the like may enter the inner side of the cover body 1 through the air holes 3, a filter screen for stopping dust and impurities can also be arranged in the air holes 3.

[0058] In another optional implementation, a concave strip groove 11 is formed on the outer top end surface of the cover body 1 used in this embodiment; and the exhaust hole 3 group includes at least air holes 3 provided on a side groove wall 111 of the strip groove 11 along the thickness direction of the cover body 1. Here, with reference to the accompanying drawings, for example, a row of air holes 3 is respectively provided on the two side groove walls 111 of the strip groove 11 along the thickness direction of the cover body 1, and each row of air holes 3 includes two air holes 3 thereon. For each side groove wall 111 of the strip groove 11 along the thickness direction of the cover body 1, the air holes 3 can be arranged in a straight line or staggered, and this embodiment does not make an absolute limitation on this. Under this design structure, it can meet the demand of exhausting the gas inside the cover body 1 through the air holes 3, and prevent dust from entering the inside of the cover body 1 through the air holes 3.

[0059] Based on the above structure, an optional situation is given in combination with the attached drawings. The number of air holes 3 designed on one of the side groove walls 111 of the strip groove 11 along the thickness direction of the cover body 1 is determined according to the number of battery cells 7 connected in series in the corresponding battery module, and at least one air hole 3 is configured for one battery cell 7. Under this structure, further, taking the waist-shaped air hole 3 as an example, assuming that the major axis size of the air hole 3 is L1, and the distance between adjacent air holes 3 is L2, then preferably, L1≤L2, such a design can ensure that the overall strength of the cover body 1 will not decrease much. Furthermore, assuming that the minor axis size of the air hole 3 is H1, and the depth of the strip groove 11 is H2, wherein H2 is based on the distance of the corresponding battery cell 7 above the middle air duct of the base 6 when the battery top cover is used in the battery module, generally H2 is about 10mm to 30mm, and H1≤H2 / 2.

[0060] In summary, for the battery top cover plate of this embodiment, the exhaust hole group and the explosion-proof group cooperate to jointly improve the safety performance of the battery module in which it is used.

[0061] Example 2: Please refer to Figures 1 to 10 As shown, based on the battery top cover plate of Example 1, this embodiment provides a battery module, including: the battery top cover plate of Example 1, a base 6, a battery cell 7 disposed between the battery top cover plate and the base 6, and at least one explosion-proof valve 5 disposed on the battery cell 7 for one-to-one cooperation with at least one explosion-proof disc 2. That is to say, there are several explosion-proof discs 2 designed for several explosion-proof valves 5, and the explosion-proof discs 2 are designed directly above the explosion-proof valves 5, so that when a large amount of exhaust gas is discharged from the battery, the explosion-proof discs 2 are opened for good exhaust.

[0062] In more detail, the explosion-proof disc 2 and the cover body 1 are integrally formed. For the explosion-proof disc 2 in this case, for example, a waist-shaped explosion-proof disc 2 and a waist-shaped through hole 4, the explosion-proof disc 2 as a whole has a structure that is thick in the middle and thin in the circumference, that is, the thickness of the edge 22 where the explosion-proof disc 2 is directly connected to the inner wall of the through hole 4 is smaller than that of other parts.

[0063] Specifically, the length and width of the explosion-proof valve 5 corresponding to one explosion-proof disc 2 are W5 and L5 respectively. The specific parameter values ​​have different sizes according to the design of the battery cell 7 used in different battery modules, and this embodiment does not make an absolute limitation. Furthermore, the long axis of the relatively thick central part 21 of the explosion-proof disc 2 (that is, the part of the overall explosion-proof disc 2 minus the edge 22 directly connected to the inner wall of the through hole 4) is L4 and the short axis is W4, and the long axis of the overall explosion-proof disc 2 is L3, and the short axis is W3; in addition, the depth of the through hole 4 is H5, the thickness of the relatively thick central part 21 of the explosion-proof disc 2 is H4, and the thickness of the edge 22 of the overall explosion-proof disc 2 directly connected to the inner wall of the through hole 4 is H3. At this time, in a specific optional implementation, 1.5×W5≥W4≥1.1×W5, 1.5×L5≥L4≥1.1×L5; 1.1×W4≥W3≥1.05×W4, 1.1×L4≥L3≥1.05×L4; and W3-W4≤2mm. H4≤0.5×H5, the thickness of H5 is between 1 and 4mm, and H3 is between 0.2 and 0.5mm.

[0064] It should be noted that the battery module of this embodiment also includes a gas detection component for detecting the concentration of gas discharged through the exhaust hole group. Based on this structure, when the battery fails and generates gas, but the pressure inside the battery does not increase to the threshold corresponding to the explosion of the explosion-proof valve 5, the exhaust holes 3 group will be used to discharge the gas generated by the battery failure, and the gas detection component will be used for detection, so as to timely identify the battery status, improve the safety of the use status, and reduce safety risks.

[0065] Specifically, the concentration of hydrogen generated when the battery fails accounts for 60% to 70% of all gases, and in the early stage of battery failure, the hydrogen concentration in the entire battery module will increase significantly. Considering that the propagation speed of hydrogen is the fastest among all gases, and the hydrogen gas content generated when the battery fails is also the highest, the gas detection component should select a hydrogen concentration sensor, which will alarm when the hydrogen concentration reaches 30% to 35%, and cut off the power to the battery module.

[0066] In summary, for the battery module of this embodiment, the purpose of pressure relief and explosion prevention is achieved by providing 2 groups of explosion-proof plates on the battery top cover plate; when the gas pressure inside the battery is too high, the explosion-proof valve 5 opens to discharge the gas, preventing the battery from exploding and threatening life safety. In addition, the exhaust hole group provided on the cover body 1 can be used to discharge the gas generated by the battery failure when the battery fails and generates gas, but before the pressure inside the battery increases to the threshold corresponding to the explosion of the explosion-proof valve 5, and the gas detection component can be used for detection, so as to timely identify the battery status, improve the safety of the use status, and reduce safety hazards.

[0067] The above specific embodiments further illustrate the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0068] In the description of the present invention, it is necessary to understand that the terms indicating orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0069] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0070] In the present utility model, unless otherwise clearly specified and limited, the first feature being above or below the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through another feature between them. Moreover, the first feature being above, above, and above the second feature includes the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being below, below, and below the second feature includes the first feature being directly below and obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

Claims

1. A battery top cover plate, characterized in that: include: Cover plate body; An exhaust hole group, comprising at least one air hole provided on the cover plate body and suitable for passing the air inside and outside the cover plate body; as well as The explosion-proof disk group comprises at least one explosion-proof disk arranged on the side wall of the cover plate body and suitable for being ruptured by the gas inside the cover plate body.

2. The battery top cover plate according to claim 1, characterized in that: The cover plate body is formed with a through hole that matches one-to-one with at least one explosion-proof disk; The through hole passes through the inside and outside of the cover plate body, and the explosion-proof sheet is suitable for covering the corresponding through hole; When the explosion-proof plate is broken by the gas inside the cover plate body, the explosion-proof plate releases the covering of the through hole, making the through hole conductive.

3. The battery top cover plate according to claim 2, characterized in that: The explosion-proof disk is integrally formed with the side wall of the cover plate body; and The thickness of the explosion-proof disk is smaller than the depth of the through hole.

4. The battery top cover plate according to claim 2, characterized in that: The explosion-proof sheet is welded, bonded or hot-pressed on the cover plate body.

5. The battery top cover plate according to any one of claims 1 to 4, characterized in that: The explosion-proof sheet is arranged on the top side wall of the cover plate body.

6. The battery top cover plate according to any one of claims 1 to 4, characterized in that: The exhaust hole group is arranged on the top side wall of the cover plate body.

7. The battery top cover plate according to any one of claims 1 to 4, characterized in that: A concave strip-shaped groove is formed on the outer top end surface of the cover body; and The exhaust hole group at least includes an exhaust hole arranged on a side groove wall of the strip-shaped groove along the thickness direction of the cover plate body.

8. The battery top cover plate according to claim 7, characterized in that: The number of air holes located on the same side groove wall of the strip-shaped groove along the thickness direction of the cover plate body is not less than two; Each of the pores is waist-shaped; and Assuming that the major axis of the pore is L1, and the distance between adjacent pores is L2, then L1≤L2.

9. A battery module, characterized in that: include: The battery top cover plate according to any one of claims 1 to 8; Base; A battery cell, wherein the battery cell is arranged between the battery top cover plate and the base; as well as The explosion-proof valve assembly comprises at least one explosion-proof valve arranged on the battery core and used for one-to-one cooperation with at least one explosion-proof disc.

10. The battery module according to claim 9, characterized in that: The battery module also includes a gas detection component for detecting the concentration of gas exhausted through the exhaust hole group.

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