Anti-explosion valve protection sheet and battery cover plate
By setting up a protective barrier on the circumferential edge of the protective substrate of the explosion-proof valve protective sheet and fixing it with an adhesive layer, the rupture problem caused by the accumulation of electrolyte overflow is solved, and resource conservation and production efficiency are improved.
Patent Information
- Application Number
- CN202510508137.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-22
- Publication Date
- 2025-07-18
AI Technical Summary
The existing explosion-proof valve protective sheets are prone to overflow and accumulation during the electrolyte injection process, resulting in rupture, increasing resource waste and production costs, and reducing production efficiency.
A protective barrier is provided on the circumferential edge of the protective substrate and fixed by an adhesive layer. The protective barrier is protruded in the direction away from the substrate, and its height and width are within a specific range to block the overflow electrolyte and avoid rupture.
Effectively prevent electrolyte overflow, avoid rupture, reduce resource waste, reduce costs, improve production efficiency, and meet fast exhaust and protection requirements.
Smart Images
Figure CN120341494A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of batteries, and particularly to an explosion-proof valve protection sheet and a battery cover plate. Background Art
[0002] With the continuous development of battery technology, the safety performance of batteries has become a key factor to be considered in battery design. The explosion-proof valve is generally formed on a light aluminum plate by integral stamping or welding. When the battery cell generates excessive gas and the internal pressure of the battery cell accumulates beyond the design value, the explosion-proof valve can burst and relieve pressure in a timely manner, playing a role in pressure relief and protection. An explosion-proof valve protection sheet is usually attached to the outside of the explosion-proof valve. The explosion-proof valve protection sheet can prevent foreign objects from falling into the explosion-proof valve area and affecting the performance of the explosion-proof valve. At the same time, during the battery liquid injection stage, the explosion-proof valve protection sheet can prevent the overflowing electrolyte from invading the explosion-proof valve, avoiding affecting the safety performance of the product and the appearance of the battery cell product.
[0003] Since the explosion-proof valve protection sheet is designed to ensure that in the event of thermal runaway, the pressure gas can quickly break through the explosion-proof valve protection sheet for discharge, the thickness of the explosion-proof valve protection sheet is usually limited to avoid being too thick and increasing the difficulty for the pressure gas to break through the explosion-proof valve protection sheet. However, in the battery manufacturing process, it is necessary to inject electrolyte into the battery, and there is a situation where the electrolyte overflows and accumulates on the surface of the battery cover plate during the injection process, and the overflowing electrolyte may flow onto the surface of the explosion-proof valve protection sheet. Due to the relatively thin thickness of the explosion-proof valve protection sheet, when the electrolyte accumulates on the explosion-proof valve protection sheet, it will cause the explosion-proof valve protection sheet to concave inward and gradually accumulate more electrolyte, ultimately resulting in the rupture of the explosion-proof valve protection sheet, leading to the need to overlap and bond the explosion-proof valve protection sheet and clean the electrolyte on the surface of the explosion-proof valve, which not only increases resource waste and cost, but also increases additional workload, wastes time, and reduces production efficiency. Summary of the Invention
[0004] The purpose of the present invention is to provide an explosion-proof valve protection sheet and a battery cover plate with less resource waste, low cost, and high production efficiency.
[0005] To achieve the above object, the present invention adopts the following technical solutions:
[0006] On the one hand, an explosion-proof valve protection sheet is provided, and the explosion-proof valve protection sheet includes:
[0007] A protection sheet body, the protection sheet body includes a protection substrate and a protection retaining platform, the protection retaining platform is continuously arranged around the circumferential edge of the protection substrate and protrudes in a direction away from the protection substrate;
[0008] An adhesive layer, the adhesive layer is continuously arranged around the circumferential edge of the protective substrate and is arranged on a side of the protective substrate away from the protective baffle, and the adhesive layer is used to fix the protective sheet body;
[0009] A height dimension of the protection stop protruding from the protection substrate along the first direction is t1, and satisfies 0.2 mm ≤ t1 ≤ 1 mm.
[0010] Optionally, a width dimension of the protective baffle along the second direction is W, and satisfies 0.5 mm ≤ W ≤ 2.5 mm.
[0011] Optionally, a thickness dimension t2 of the protective substrate along the first direction satisfies 0.05mm≤t2≤0.3mm.
[0012] Optionally, a thickness of the adhesive layer along the first direction is t3, and satisfies 0.05 mm ≤ t3 ≤ 0.15 mm.
[0013] Optionally, the protective substrate is provided with a plurality of symmetrically distributed scoring lines.
[0014] Optionally, the plurality of score lines are parallel to each other or intersect at one point.
[0015] Optionally, the protection sheet body is coated with a color coating.
[0016] Optionally, the protective sheet body is made of PET, PC, PP, PVC or PE material.
[0017] Optionally, the adhesive layer is made of pressure-sensitive adhesive or heat-sensitive adhesive.
[0018] On the other hand, a battery cover is provided, which includes a cover body, an explosion-proof valve and an explosion-proof valve protection sheet as described in any of the above items, wherein a mounting hole is opened on the cover body, the explosion-proof valve is arranged in the mounting hole, and the explosion-proof valve protection sheet is connected to the cover body and is used to close the mounting hole.
[0019] Beneficial effects of the present invention:
[0020] The present invention provides an explosion-proof valve protection sheet. By providing a protective retaining platform around the circumferential edge of the protective substrate on the protection sheet body and making the protective retaining platform protrude in a direction away from the protective substrate, when the protection sheet body is fixed through an adhesive layer, when the electrolyte injection process is carried out and overflows, the overflowing electrolyte will be blocked by the protective retaining platform of the protection sheet body, so that the overflowing electrolyte cannot flow to the surface of the protective substrate, avoiding the problem that the electrolyte accumulates on the surface of the relatively thin protective substrate and causing rupture. This not only avoids resource waste and cost increase caused by the rupture of the explosion-proof valve protection sheet, but also avoids the extra work of replacing the explosion-proof valve protection sheet and cleaning the electrolyte, saving time and improving work efficiency. In addition, by limiting the height dimension t1, on the one hand, it avoids the situation where the height of the protective retaining platform is too low to effectively block the electrolyte, and on the other hand, it avoids the situation where the height of the protective retaining platform is too high, resulting in cost waste.
[0021] The present invention also provides a battery cover plate. By applying the above-mentioned explosion-proof valve protection sheet, the manufacturing cost is reduced and the production efficiency is improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 is a schematic structural diagram of the explosion-proof valve protection sheet provided by the present invention;
[0023] Figure 2 is a structural cross-sectional view of the explosion-proof valve protection sheet provided by the present invention;
[0024] Figure 3 is Figure 2 an enlarged structural view of part A in
[0025] Figure 4 is a schematic diagram of the explosion-proof valve protection sheet provided by the present invention applied to a square shell battery.
[0026] In the figure:
[0027] 100, cover plate body;
[0028] 1, protection sheet body; 11, protective substrate; 12, protective retaining platform; 13, scoring line;
[0029] 2, adhesive layer. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0030] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the sake of description, only parts related to the present invention are shown in the drawings, rather than all the structures.
[0031] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0032] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over", and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "beneath", and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.
[0033] In the description of this embodiment, the orientation or positional relationships such as "above", "below", "right", etc. are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description and simplifying the operation, 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 thus should not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.
[0034] Since the explosion-proof valve protection piece is designed to quickly exhaust gas during thermal runaway, its thickness is relatively thin. As a result, during the electrolyte injection process, the electrolyte is likely to accumulate on the explosion-proof valve protection piece due to overflow, causing the explosion-proof valve protection piece to rupture, which increases resource waste, raises costs, and also increases additional workload, wastes time, and reduces production efficiency.
[0035] Therefore, in order to ensure that the explosion-proof valve protection piece has the function of quickly exhausting gas while avoiding the rupture of the explosion-proof valve protection piece caused by the accumulation of electrolyte on it, reducing resource waste, lowering costs, and improving production efficiency, this embodiment provides an explosion-proof valve protection piece.
[0036] Such as Figures 1 to 4As shown in the figure, the explosion-proof valve protection sheet includes a protection sheet body 1 and an adhesive layer 2. The protection sheet body 1 includes a protection substrate 11 and a protection stop 12. The protection stop 12 is continuously arranged around the circumferential edge of the protection substrate 11 and protrudes in a direction away from the protection substrate 11. The adhesive layer 2 is continuously arranged around the circumferential edge of the protection substrate 11 and is arranged on the side of the protection substrate 11 facing away from the protection stop 12. The adhesive layer 2 is used to fix the protection sheet body 1. The height dimension of the protection stop 12 protruding from the protection substrate 11 in the first direction is t1, and it satisfies 0.2mm ≤ t1 ≤ 1mm.
[0037] The explosion-proof valve protection sheet is provided with a protection stop 12 around the circumferential edge of the protection substrate 11 on the protection substrate 11 of the protection sheet body 1, and the protection stop 12 protrudes in a direction away from the protection substrate 11. When the protection sheet body 1 is fixed through the adhesive layer 2, when the electrolyte injection process is carried out and overflow occurs, the overflowing electrolyte will be blocked by the protection stop 12 of the protection sheet body 1, so that the overflowing electrolyte cannot flow to the surface of the protection substrate 11, avoiding the problem that the electrolyte accumulates on the surface of the relatively thin protection substrate 11 and causes rupture. This not only avoids resource waste and cost increase caused by the rupture of the explosion-proof valve protection sheet, but also avoids the extra work of replacing the explosion-proof valve protection sheet and cleaning the electrolyte, saving time and improving work efficiency. In addition, by limiting the height dimension t1, on the one hand, it avoids the protection stop 12 being too low in height to effectively block the electrolyte, and on the other hand, it avoids the protection stop 12 being too high in height and wasting costs.
[0038] In this embodiment, the protection sheet body 1 is prepared from materials such as PET, PC, PP, PVC or PE, and the adhesive layer 2 is prepared from a pressure-sensitive adhesive or a heat-sensitive adhesive.
[0039] Among them, the explosion-proof valve protection sheet can be used on different types of batteries, such as blade batteries, square shell batteries or large cylindrical batteries, etc. The position where the explosion-proof valve protection sheet is pasted is determined according to the position where the explosion-proof valve is set. If the explosion-proof valve is set on the battery cover plate, the explosion-proof valve protection sheet is also set on the battery cover plate. If the explosion-proof valve is set on the battery case, the explosion-proof valve protection sheet is also set on the battery case. In this embodiment, as Figure 4 shown, the explosion-proof valve protection sheet is set on the battery cover plate of the square shell battery.
[0040] Optionally, as Figure 2 、 Figure 3As shown, the width dimension W of the protective retaining platform 12 in the second direction is such that 0.5 mm ≤ W ≤ 2.5 mm. By limiting the width dimension W of the protective retaining platform 12 in the second direction to satisfy 0.5 mm ≤ W ≤ 2.5 mm, on the one hand, it is possible to avoid the width of the protective retaining platform 12 in the second direction being too large, which would compress the area of the protective substrate 11 for exhaust and reduce the exhaust speed. On the other hand, it is possible to avoid the width of the protective retaining platform 12 in the second direction being too small, which would reduce the strength of the protective retaining platform 12 to resist impacts in the second direction.
[0041] In this embodiment, the width dimension W of the protective retaining platform 12 in the second direction can be any value between 0.5 mm and 2.5 mm or the range between any two values, such as 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, etc.
[0042] Optionally, as Figure 2 、 Figure 3 shown, the thickness dimension t2 of the protective substrate 11 in the first direction satisfies 0.05 mm ≤ t2 ≤ 0.3 mm. By limiting the thickness dimension t2 of the protective substrate 11 in the first direction to satisfy 0.05 mm ≤ t2 ≤ 0.3 mm, on the one hand, it is possible to avoid the thickness of the protective substrate 11 being too small to provide protection. On the other hand, it is possible to avoid the thickness of the protective substrate 11 being too large, which would increase the resistance when the pressurized gas breaks through the protective substrate 11 and fail to meet the requirement of rapid exhaust.
[0043] In this embodiment, the thickness dimension t2 of the protective substrate 11 in the first direction can be any value between 0.05 mm and 0.3 mm or the range between any two values, such as 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, etc.
[0044] Optionally, as Figure 2 、 Figure 3 shown, the thickness of the adhesive layer 2 in the first direction is t3 and satisfies 0.05 mm ≤ t3 ≤ 0.15 mm. By limiting the thickness dimension t3 of the adhesive layer 2 in the first direction, on the one hand, it is possible to avoid the adhesive layer 2 being too thin, resulting in poor bonding strength for the protective sheet body 1 and causing the protective sheet body 1 to easily fall off. On the other hand, it is possible to avoid the adhesive layer 2 being too thick, resulting in glue overflow during bonding and causing the adhesive layer 2 to overflow onto other areas that do not require bonding.
[0045] In this embodiment, the thickness dimension t3 of the adhesive layer 2 in the first direction can be any value between 0.05 mm and 0.15 mm or the range between any two values, such as 0.05 mm, 0.1 mm, 0.15 mm, etc.
[0046] In this embodiment, in order to confirm the influence of the height dimension t1 of the protective retaining platform 12 protruding along the first direction, the width dimension W of the protective retaining platform 12 along the second direction, the thickness dimension t2 of the protective substrate 11 along the first direction, and the thickness t3 of the adhesive layer 2 along the first direction on the rapid exhaust and protection of the explosion-proof valve protection sheet, as shown in Table 1, six groups of embodiments and seven groups of comparative examples are provided for verification.
[0047] When verifying the protection performance, first bond the explosion-proof valve protection sheet, and then perform the electrolyte injection process. If no electrolyte is found on the surface of the protective substrate 11, the protection performance is qualified; if electrolyte is found on the surface of the protective substrate 11, the protection performance is unqualified. When verifying the exhaust performance, introduce pressure gas that can open the explosion-proof valve into the closed battery housing. If the time for the explosion-proof valve protection sheet to be opened is less than 0.1 s, the requirement for rapid exhaust is met; if the time for the explosion-proof valve protection sheet to be opened is greater than 0.1 s, the requirement for rapid exhaust is not met. Also, observe whether the area where the protection sheet body 1 is bonded by the adhesive layer 2 is separated. If the area where the protection sheet body 1 is bonded by the adhesive layer 2 remains bonded after the explosion-proof valve protection sheet is opened, the bonding strength meets the requirement; if the area where the protection sheet body 1 is bonded by the adhesive layer 2 is separated, the requirement for bonding strength is not met.
[0048] Table 1
[0049]
[0050] In Embodiment 1, the height dimension t1 of the protective retaining platform 12 protruding along the first direction is set to 0.2 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 along the second direction is set to 0.5 mm, meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 along the first direction is set to 0.05 mm, meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 along the first direction is set to 0.05 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte is found on the surface of the protective substrate 11, and when the pressure gas opens the explosion-proof valve, the time to break through the explosion-proof valve protection sheet is 0.025 s, which is less than the specified 0.1 s. After the test, the protection sheet body 1 and the bonding area are not separated.
[0051] In Embodiment 2, the height dimension t1 of the protective retaining platform 12 protruding along the first direction is set to 0.3 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 along the second direction is set to 0.75 mm, meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 along the first direction is set to 0.1 mm, meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 along the first direction is set to 0.07 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte is found on the surface of the protective substrate 11. And when the pressure gas opens the explosion-proof valve, the time taken to break through the explosion-proof valve protection piece is 0.033 s, which is less than the specified 0.1 s. And after the test, the protection piece body 1 is not separated from the bonding area.
[0052] In Embodiment 3, the height dimension t1 of the protective retaining platform 12 protruding along the first direction is set to 0.4 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 along the second direction is set to 1.5 mm, meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 along the first direction is set to 0.15 mm, meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 along the first direction is set to 0.09 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte is found on the surface of the protective substrate 11. And when the pressure gas opens the explosion-proof valve, the time taken to break through the explosion-proof valve protection piece is 0.042 s, which is less than the specified 0.1 s. And after the test, the protection piece body 1 is not separated from the bonding area.
[0053] In Embodiment 4, the height dimension t1 of the protective retaining platform 12 protruding along the first direction is set to 0.6 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 along the second direction is set to 1.75 mm, meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 along the first direction is set to 0.2 mm, meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 along the first direction is set to 0.11 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte is found on the surface of the protective substrate 11. And when the pressure gas opens the explosion-proof valve, the time taken to break through the explosion-proof valve protection piece is 0.062 s, which is less than the specified 0.1 s. And after the test, the protection piece body 1 is not separated from the bonding area.
[0054] In Example 5, the height dimension t1 of the protective retaining platform 12 protruding along the first direction is set to 0.8 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 along the second direction is set to 2 mm, meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 along the first direction is set to 0.25 mm, meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 along the first direction is set to 0.13 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte is found on the surface of the protective substrate 11. And when the pressure gas opens the explosion-proof valve, the time taken to break through the explosion-proof valve protection sheet is 0.075 s, which is less than the specified 0.1 s. And after the test, the protection sheet body 1 and the bonding area are not separated.
[0055] In Example 6, the height dimension t1 of the protective retaining platform 12 protruding along the first direction is set to 1 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 along the second direction is set to 2.5 mm, meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 along the first direction is set to 0.3 mm, meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 along the first direction is set to 0.15 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte is found on the surface of the protective substrate 11. And when the pressure gas opens the explosion-proof valve, the time taken to break through the explosion-proof valve protection sheet is 0.086 s, which is less than the specified 0.1 s. And after the test, the protection sheet body 1 and the bonding area are not separated.
[0056] It can be seen from Examples 1 to 6 that when the height dimension t1 of the protective retaining platform 12 protruding along the first direction, the width dimension W of the protective retaining platform 12 along the second direction, the thickness dimension t2 of the protective substrate 11 along the first direction, and the thickness t3 of the adhesive layer 2 along the first direction all meet their respective dimension limit requirements, after the detection test, no electrolyte is found on the surface of the protective substrate 11. And when the pressure gas opens the explosion-proof valve, the time taken to break through the explosion-proof valve protection sheet is less than the specified 0.1 s. And after the test, no separation phenomenon is found in the area where the protection sheet body 1 is bonded to the adhesive layer 2. Therefore, the requirements for rapid exhaust and protection are met, and the product is qualified.
[0057] In Comparative Example 1, the height dimension t1 of the protective retaining platform 12 protruding in the first direction is set to 0.1 mm, which does not meet the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 in the second direction is set to 0.5 mm, which meets the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 in the first direction is set to 0.05 mm, which meets the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 in the first direction is set to 0.05 mm, which meets the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, electrolyte is found on the surface of the protective substrate 11. When the pressure gas opens the explosion-proof valve, the time taken to break through the explosion-proof valve protection sheet is 0.025 s, which is less than the specified 0.1 s. And after the test, the protection sheet body 1 and the bonding area are not separated.
[0058] In Comparative Example 2, the height dimension t1 of the protective retaining platform 12 protruding in the first direction is set to 1.5 mm, which does not meet the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 in the second direction is set to 0.75 mm, which meets the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 in the first direction is set to 0.1 mm, which meets the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 in the first direction is set to 0.07 mm, which meets the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte is found on the surface of the protective substrate 11. And when the pressure gas opens the explosion-proof valve, the time taken to break through the explosion-proof valve protection sheet is 0.033 s, which is less than the specified 0.1 s. And after the test, the protection sheet body 1 and the bonding area are not separated, but the manufacturing cost of the explosion-proof valve protection sheet increases.
[0059] It can be seen from Comparative Example 1 that when the height dimension t1 of the protective retaining platform 12 protruding in the first direction is less than the minimum value of 0.2 mm ≤ t1 ≤ 1 mm, at this time, due to the too low height of the protrusion of the protective retaining platform 12, when injecting electrolyte, the electrolyte can still cross the protective retaining platform 12 and accumulate on the protective substrate 11. Therefore, there is still a risk of damage to the protective substrate 11 due to the accumulated electrolyte. Therefore, it does not meet the protection requirements and the product is unqualified.
[0060] As can be seen from Comparative Example 2, when the height dimension t1 of the protective retaining platform 12 protruding in the first direction is greater than the maximum value of 0.2 mm ≤ t1 ≤ 1 mm, although no electrolyte is found on the surface of the protective substrate 11 at this time, and when the pressure gas blows open the explosion-proof valve, the time to break through the explosion-proof valve protection sheet is less than the specified 0.1 s, and after the test is over, no detachment is found in the area where the protection sheet body 1 is adhered by the adhesive layer 2, meeting the requirements of rapid exhaust and protection. However, due to the excessive height of the protective retaining platform 12 protruding, the manufacturing cost of the explosion-proof valve protection sheet increases, which does not meet the requirements of cost reduction and efficiency improvement.
[0061] In Comparative Example 3, the height dimension t1 of the protective retaining platform 12 protruding in the first direction is set to 0.4 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 in the second direction is set to 0.2 mm, not meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 in the first direction is set to 0.15 mm, meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 in the first direction is set to 0.09 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, electrolyte is found on the surface of the protective substrate 11. When the pressure gas blows open the explosion-proof valve, the time to break through the explosion-proof valve protection sheet is 0.042 s, which is less than the specified 0.1 s, and after the test is over, the protection sheet body 1 and the bonding area are not separated.
[0062] In Comparative Example 4, the height dimension t1 of the protective retaining platform 12 protruding in the first direction is set to 0.6 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 in the second direction is set to 3 mm, not meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 in the first direction is set to 0.2 mm, meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 in the first direction is set to 0.11 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte is found on the surface of the protective substrate 11, and when the pressure gas blows open the explosion-proof valve, the time to break through the explosion-proof valve protection sheet is 0.12 s, which is greater than the specified 0.1 s, and after the test is over, the protection sheet body 1 and the bonding area are not separated.
[0063] As can be seen from Comparative Example 3, when the width dimension W of the protective retaining table 12 in the second direction is less than the minimum value of 0.5 mm ≤ W ≤ 2.5 mm, since the width of the protective retaining table 12 in the second direction is small at this time, the strength of the protective retaining table 12 against the impact force in the second direction is poor. As a result, when injecting the electrolyte, the impact force of the electrolyte causes the protective retaining table 12 to deform, so that the electrolyte passes over the protective retaining table 12 and accumulates on the protective substrate 11. Therefore, there is still a risk that the protective substrate 11 is damaged due to the accumulated electrolyte, so it does not meet the requirements of protection, and the product is unqualified.
[0064] As can be seen from Comparative Example 4, when the width dimension W of the protective retaining table 12 in the second direction is greater than the maximum value of 0.5 mm ≤ W ≤ 2.5 mm, since the width of the protective retaining table 12 in the second direction is too large at this time, the area of the protective substrate 11 for opening the exhaust is reduced, resulting in a decrease in the exhaust speed. Specifically, the time for the pressure gas to break through the explosion-proof valve protection sheet is greater than the specified 0.1 s. Therefore, it does not meet the requirement of rapid exhaust, and the product is unqualified.
[0065] In Comparative Example 5, the height dimension t1 of the protective retaining table 12 protruding in the first direction is set to 0.8 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining table 12 in the second direction is set to 2 mm, meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 in the first direction is set to 0.03 mm, not meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 in the first direction is set to 0.13 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, the protective substrate 11 is damaged, and when the pressure gas opens the explosion-proof valve, the time for breaking through the explosion-proof valve protection sheet is 0.062 s, which is less than the specified 0.1 s, and after the test is over, the protection sheet body 1 and the bonding area are not separated.
[0066] In Comparative Example 6, the height dimension t1 of the protective retaining platform 12 protruding in the first direction is set to 1 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 in the second direction is set to 2.5 mm, meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 in the first direction is set to 0.5 mm, not meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 in the first direction is set to 0.15 mm, meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte was found on the surface of the protective substrate 11. And when the pressure gas opened the explosion-proof valve, the time taken to break through the explosion-proof valve protection piece was 0.23 s, which is greater than the specified 0.1 s. And after the test ended, the protection piece body 1 was not separated from the bonding area.
[0067] As can be seen from Comparative Example 5, when the thickness dimension t2 of the protective substrate 11 in the first direction is less than the minimum value of 0.05 mm ≤ t2 ≤ 0.3 mm, due to the overly thin thickness of the protective substrate 11, during the production and assembly process, the protective substrate 11 was damaged due to external environmental factors, and thus could not effectively protect the explosion-proof valve. Therefore, the product was unqualified.
[0068] As can be seen from Comparative Example 6, when the thickness dimension t2 of the protective substrate 11 in the first direction is greater than the maximum value of 0.05 mm ≤ t2 ≤ 0.3 mm, due to the overly thick thickness of the protective substrate 11, the resistance of the pressure gas when impacting the protective substrate 11 is large, resulting in the time taken for the pressure gas to break through the explosion-proof valve protection piece being greater than the specified 0.1 s. Therefore, it does not meet the requirement of rapid exhaust, and the product is unqualified.
[0069] In Comparative Example 7, the height dimension t1 of the protective retaining platform 12 protruding in the first direction is set to 1 mm, meeting the range requirement of 0.2 mm ≤ t1 ≤ 1 mm. The width dimension W of the protective retaining platform 12 in the second direction is set to 2.5 mm, meeting the range requirement of 0.5 mm ≤ W ≤ 2.5 mm. The thickness dimension t2 of the protective substrate 11 in the first direction is set to 0.3 mm, meeting the range requirement of 0.05 mm ≤ t2 ≤ 0.3 mm. The thickness t3 of the adhesive layer 2 in the first direction is set to 0.02 mm, not meeting the range requirement of 0.05 mm ≤ t3 ≤ 0.15 mm. At this time, after the detection test, no electrolyte was found on the surface of the protective substrate 11. And when the pressure gas opened the explosion-proof valve, the time taken to break through the explosion-proof valve protection piece was 0.071 s, which is less than the specified 0.1 s. And after the test ended, the protection piece body 1 was separated from the bonding area.
[0070] As can be seen from Comparative Example 7, when the thickness t3 of the adhesive layer 2 in the first direction is less than the minimum value of 0.05 mm ≤ t3 ≤ 0.15 mm, due to the too small thickness of the adhesive layer 2, the adhesive force on the protective sheet body 1 is poor, resulting in the separation of the protective sheet body 1 from the bonding area under the impact of the pressure gas, causing the explosion-proof valve protective sheet to fall off, and the product quality is poor and the product is unqualified.
[0071] Optionally, a plurality of symmetrically distributed scoring lines 13 are provided on the protective substrate 11. By providing a plurality of symmetrically distributed scoring lines 13 on the protective substrate 11, the structural strength of the protective substrate 11 is weakened, thereby reducing the resistance when the pressure gas breaks through the protective substrate 11 and realizing the function of rapid exhaust.
[0072] Optionally, as Figure 1 , Figure 2 shown, the plurality of scoring lines 13 are parallel to each other. By providing a plurality of mutually parallel scoring lines 13, the structural strength of each region of the protective substrate 11 divided by the plurality of parallel scoring lines 13 is ensured to be the same, so that when the pressure gas impacts the protective substrate 11, each region of the protective substrate 11 divided by the parallel scoring lines 13 can be opened simultaneously, thus achieving the effect of rapid exhaust.
[0073] Optionally, the plurality of scoring lines 13 intersect at a point. By making the plurality of scoring lines 13 intersect at a point, when the pressure gas impacts the protective substrate 11, when one of the scoring lines 13 cracks, it is easier to transfer the impact force to another scoring line 13, causing the plurality of scoring lines 13 to crack quickly, thereby achieving the effect of rapid exhaust.
[0074] The number of the scoring lines 13 can be freely set according to requirements, and it can be freely selected whether the scoring lines 13 are parallelly distributed or intersectingly distributed. In this embodiment, as Figure 1 shown, the protective substrate 11 adopts two mutually parallel scoring lines 13.
[0075] Optionally, a color coating is applied to the outer surface of the protective sheet body 1. By applying a color coating to the outer surface of the protective sheet body 1, it can be clearly and intuitively recognized whether the explosion-proof valve protective sheet is installed during assembly, avoiding the problem of missing installation.
[0076] In this embodiment, as Figure 4 shown, a battery cover plate is further provided. The battery cover plate includes a cover plate body 100, an explosion-proof valve and the above-mentioned explosion-proof valve protective sheet. An installation hole is provided on the cover plate body 100. The explosion-proof valve is arranged in the installation hole. The explosion-proof valve protective sheet is connected to the cover plate body 100 and is used to close the installation hole. By applying the above-mentioned explosion-proof valve protective sheet, the manufacturing cost of the battery cover plate is reduced and the production efficiency is improved.
[0077] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to enumerate all implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the claims of the present invention.
Claims
1. Explosion-proof valve protection piece, characterized in that, The explosion-proof valve protection sheet includes: A protection sheet body, which includes a protection substrate and a protection retaining platform. The protection retaining platform is continuously arranged around the circumferential edge of the protection substrate and protrudes in a direction away from the protection substrate; An adhesive layer, which is continuously arranged around the circumferential edge of the protection substrate and is arranged on the side of the protection substrate facing away from the protection retaining platform. The adhesive layer is used to fix the protection sheet body; The height dimension of the protection retaining platform protruding from the protection substrate in the first direction is t1, and it satisfies 0.2mm ≤ t1 ≤ 1mm.
2. The explosion-proof valve protection piece according to claim 1, wherein The width dimension of the protection retaining platform in the second direction is W, and it satisfies 0.5mm ≤ W ≤ 2.5mm.
3. The explosion-proof valve protection piece according to claim 1, characterized in that, The thickness dimension t2 of the protection substrate in the first direction satisfies 0.05mm ≤ t2 ≤ 0.3mm.
4. The explosion-proof valve protection piece according to claim 1, wherein The thickness of the adhesive layer in the first direction is t3, and it satisfies 0.05mm ≤ t3 ≤ 0.15mm.
5. The explosion-proof valve protection piece according to claim 1, wherein, A plurality of symmetrically distributed scoring lines are provided on the protection substrate.
6. The explosion-proof valve protection piece according to claim 5, wherein, The plurality of scoring lines are parallel to each other or intersect at a point.
7. The explosion-proof valve protection piece according to claim 1, wherein A color coating is applied on the outer surface of the protection sheet body.
8. The explosion-proof valve protection piece according to claim 1, wherein, The protection sheet body is prepared from PET, PC, PP, PVC or PE materials.
9. The explosion-proof valve protection piece according to claim 1, characterized in that, The adhesive layer is prepared from a pressure-sensitive adhesive or a heat-sensitive adhesive.
10. Battery cover plate, characterized in that, The battery cover plate includes a cover plate body, an explosion-proof valve and the explosion-proof valve protection sheet according to any one of claims 1-9. An installation hole is provided on the cover plate body. The explosion-proof valve is arranged in the installation hole. The explosion-proof valve protection sheet is connected to the cover plate body and is used to close the installation hole.