Battery and battery pack
By opening multiple overflow holes on the electrodes of the lithium-ion battery, the problem of enlarging the electrodes blocking the explosion-proof valve and affecting the exhaust efficiency is solved, and efficient exhaust and safety improvement is achieved.
Patent Information
- Application Number
- CN202510269767.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-07
- Publication Date
- 2025-06-06
AI Technical Summary
While meeting the overcurrent needs, the increase in the ears of existing lithium-ion batteries leads to blocking explosion-proof valves, affecting exhaust efficiency, and posing safety hazards.
A plurality of overflow holes are opened on the pole ears, so that the pole ears that block the explosion-proof valve can achieve smooth flow of pressure gas generated by thermal runaway through these holes, and ensure exhaust efficiency by defining the ratio of the total area of the overflow hole to the projected area of the explosion-proof valve.
It achieves high exhaust efficiency while meeting the overcurrent needs, avoids safety hazards caused by untimely exhaust pressure relief, and improves battery safety.
Smart Images
Figure CN120109452A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of batteries, and in particular to a battery and a battery pack. Background Art
[0002] Lithium-ion batteries are currently widely used in various fields such as transportation power supply, electric energy storage power supply, new energy storage power supply, aerospace and military industry due to their large capacity, high operating voltage, strong charge retention ability and long cycle life. The structure of a single lithium battery generally includes a pole group, electrolyte, cover plate, shell, internal and external insulation structure, etc. The cover plate and shell are usually fixed by laser welding to form a closed space with a certain structural strength to protect the pole group. The cover plate is generally integrated with functional areas such as pole column, explosion-proof valve, and injection hole. The pole group is fixed by laser welding the pole ear and the pole column base of the cover plate to achieve electrical connection, thereby leading the internal current of the battery cell to the outside of the shell.
[0003] However, with the continuous increase in the demand for single battery capacity, charge and discharge rate, and fast charging, the width of the tab has become a key factor restricting the internal structure of the battery cell. The higher the overcurrent demand, the larger the area of the tab is required for the same foil thickness and number of layers. As a result, in order to meet the overcurrent demand, the area of the tab is increased, which will block the exhaust channel of the explosion-proof valve, thereby affecting the exhaust efficiency of the explosion-proof valve. There are safety hazards caused by untimely exhaust pressure relief, and the safety is poor. Summary of the invention
[0004] The object of the present invention is to provide a battery and a battery pack, which meet the overcurrent requirements and have high exhaust efficiency, avoid the potential safety hazards caused by untimely exhaust pressure relief, and have good safety.
[0005] To achieve this object, the present invention adopts the following technical solutions:
[0006] In one aspect, a battery is provided, comprising:
[0007] A cover plate assembly, the cover plate assembly comprising a cover plate body, a pole and an explosion-proof valve, wherein the pole and the explosion-proof valve are both arranged on the cover plate body;
[0008] A pole group, the pole group comprising a pole lug, the pole lug being bent and welded to the pole column;
[0009] A plurality of flow holes are provided on the pole ear, the total area of the plurality of flow holes is S1, the area of the explosion-proof valve projected on the pole ear along the third direction is S2, and 0.5≤S1 / S2≤0.7 is satisfied.
[0010] Optionally, the effective opening area of the explosion-proof valve is S0, and satisfies S2 / S0≤0.5.
[0011] Optionally, the cover plate assembly further includes an insulating member, wherein the insulating member is disposed between the cover plate body and the pole group, wherein a ventilation area corresponding to the explosion-proof valve is provided on the insulating member, wherein a ventilation structure connected to the explosion-proof valve is provided in the ventilation area, and an area of the ventilation area is S3, and satisfies 1.1≤S3 / S0≤1.3.
[0012] Optionally, the ventilation structure is a plurality of ventilation holes, the total area of the plurality of ventilation holes is S4, and 0.4≤S4 / S0≤0.7 is satisfied.
[0013] Optionally, a spacing dimension between the explosion-proof valve and the pole adjacent thereto along the first direction is L1, and satisfies 6mm≤L1≤20mm.
[0014] Optionally, the electrode tab includes a first boundary formed after bending, and a spacing dimension between the first boundary and the flow hole adjacent thereto along the second direction is L2, and satisfies 4mm≤L2≤7mm.
[0015] Optionally, the tab further includes a second boundary opposite to the first boundary along the second direction, and a spacing dimension between the second boundary and the adjacent flow hole along the second direction is L3, and satisfies 2mm≤L3≤3mm.
[0016] Optionally, the electrode ear further includes a third boundary perpendicular to the first boundary and located below the explosion-proof valve, and the spacing dimension between the third boundary and the adjacent flow hole along the first direction is L4, and satisfies 2mm≤L4≤3mm.
[0017] Optionally, the projection of the flow hole adjacent to the pole along the third direction on the cover body covers part of the explosion-proof valve, and the shortest length dimension of the area of the flow hole adjacent to the pole that does not cover the explosion-proof valve along the first direction is L5, and satisfies 1mm≤L5≤7mm.
[0018] On the other hand, a battery pack is provided, comprising a battery pack case and a battery as described in any one of the above items, wherein a plurality of the batteries are disposed in the battery pack case.
[0019] Beneficial effects of the present invention:
[0020] The present invention provides a battery, which, by providing a plurality of flow holes on a pole ear, enables the pole ear that blocks an explosion-proof valve to achieve smooth flow of pressurized gas generated by thermal runaway through the plurality of flow holes, thereby reducing the influence of the pole ear that blocks the explosion-proof valve on the exhaust efficiency of the explosion-proof valve, and by limiting the ratio of the total area S1 of the plurality of flow holes and the area S2 of the explosion-proof valve projected onto the pole ear along a third direction, so that the ratio satisfies 0.5≤S1 / S2≤0.7, thereby, on the one hand, ensuring that the total area S1 of the plurality of flow holes is large enough to meet the gas flow rate requirement of the explosion-proof valve during exhaust, and on the other hand, avoiding that the total area S1 of the plurality of flow holes is too large, thereby weakening the structural strength of the pole ear and causing the pole ear to be easily deformed, so that the battery has a higher exhaust efficiency while meeting the flow requirement, avoiding the potential safety hazard caused by untimely exhaust pressure relief, and having good safety.
[0021] The present invention also provides a battery pack, which, by applying the above-mentioned battery, has higher safety in use, improved structural reliability, and optimized product quality. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a schematic diagram of the unfolded three-dimensional structure of the battery provided by the present invention after the cover plate assembly and the electrode group are welded;
[0023] Figure 2 It is a schematic diagram of the folded three-dimensional structure of the battery provided by the present invention after the cover plate assembly and the electrode group are welded;
[0024] Figure 3 It is a schematic diagram of the planar structure of the battery provided by the present invention after the cover plate assembly and the electrode group are welded;
[0025] Figure 4 yes Figure 3 A magnified view of the structure of part A;
[0026] Figure 5 yes Figure 4 A magnified view of the structure of part B;
[0027] Figure 6 It is a structural plan view of the cover plate assembly in the battery provided by the present invention.
[0028] In the figure:
[0029] 1. Cover plate assembly; 11. Cover plate body; 12. Pole; 13. Explosion-proof valve; 131. Opening boundary; 14. Insulating member; 141. Ventilation hole;
[0030] 2. Pole group; 21. Pole ear; 211. First boundary; 212. Second boundary; 213. Third boundary; 22. Current hole. DETAILED DESCRIPTION
[0031] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.
[0032] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" 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.
[0033] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.
[0034] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.
[0035] In order to meet the flow demand, the area of the pole ear is increased, which will block the exhaust channel of the explosion-proof valve, thereby affecting the exhaust efficiency of the explosion-proof valve and resulting in poor safety.
[0036] Therefore, in order to meet the overflow requirement while having a higher exhaust efficiency, avoid the potential safety hazard caused by untimely exhaust pressure relief, and improve safety, this embodiment provides a battery.
[0037] like Figures 1 to 6As shown, the battery includes a cover assembly 1 and a pole group 2, the cover assembly 1 includes a cover body 11, a pole 12 and an explosion-proof valve 13, the pole 12 and the explosion-proof valve 13 are both arranged on the cover body 11, the pole group 2 includes a pole ear 21, the pole ear 21 is bent and welded to the pole 12, a plurality of flow holes 22 are opened on the pole ear 21, the total area of the plurality of flow holes 22 is S1, the area of the explosion-proof valve 13 projected on the pole ear 21 along the third direction is S2, and 0.5≤S1 / S2≤0.7 is satisfied.
[0038] The battery has a plurality of flow holes 22 on the pole ear 21, so that the pole ear 21 that blocks the explosion-proof valve 13 can realize smooth flow of pressurized gas generated by thermal runaway through the plurality of flow holes 22, thereby reducing the influence of the pole ear 21 that blocks the explosion-proof valve 13 on the exhaust efficiency of the explosion-proof valve 13, and by limiting the ratio of the total area S1 of the plurality of flow holes 22 and the area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction, so that they satisfy 0.5≤S1 / S2≤0.7, thereby ensuring that the total area S1 of the plurality of flow holes 22 is large enough to meet the gas flow rate requirement of the explosion-proof valve 13 during exhaust, and avoiding the total area S1 of the plurality of flow holes 22 being too large, thereby weakening the structural strength of the pole ear 21 and causing the pole ear 21 to be easily deformed, so that the battery has a higher exhaust efficiency while meeting the flow requirement, avoiding the potential safety hazard caused by untimely exhaust pressure relief, and having good safety.
[0039] The battery provided in this embodiment can be of various types, such as blade batteries or square shell batteries, and the shape of the flow hole 22 opened on the pole ear 21 can be freely set according to needs, such as circular, polygonal or runway shape, etc., as long as it is a shape that is convenient for production and realization. In this embodiment, the flow hole 22 is a circular hole with a radius of R1. The number of the flow holes 22 opened on the pole ear 21 is set to N1. At this time, the total area of the multiple flow holes 22 is S1 = N1·πR1 2 .
[0040] Alternatively, if Figure 1 , Figure 3 As shown, the effective opening area of the explosion-proof valve 13 is S0, and S2 / S0≤0.5 is satisfied. By setting the effective opening area of the explosion-proof valve 13 to S0, and limiting the ratio between the area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction and the effective opening area S0 of the explosion-proof valve 13, it is prevented that the pole ear 21 blocks too large an area of the explosion-proof valve 13, thereby reducing the exhaust efficiency of the exhaust valve.
[0041] Alternatively, if Figure 1 , Figure 6As shown, the cover plate assembly 1 also includes an insulating member 14, which is arranged between the cover plate body 11 and the pole group 2. The insulating member 14 is provided with a ventilation area corresponding to the explosion-proof valve 13, and the area of the ventilation area is S3, and satisfies 1.1≤S3 / S0≤1.3. Since it is necessary to avoid abnormal problems such as short circuit caused by direct contact between the pole ear 21 and the cover plate body 11, the cover plate assembly 1 is usually provided with an insulating member 14 for insulating and protecting the cover plate body 11. Therefore, in order to ensure smooth discharge of gas, it is necessary to provide a ventilation structure connected to the explosion-proof valve 13 on the insulating member 14, so that the gas can be discharged through the insulating member 14. By limiting the ratio between the area S3 of the exhaust area on the insulating member 14 and the effective opening area S0 of the explosion-proof valve 13, it is ensured that the insulating member 14 has enough area to set the ventilation structure for meeting the exhaust requirements of the explosion-proof valve 13, thereby ensuring the flow rate of the gas when passing through the insulating member 14, and reducing the impact on the exhaust efficiency of the exhaust valve.
[0042] Specifically, Figure 1 , Figure 6 As shown, the ventilation structure is a plurality of ventilation holes 141, the total area of the plurality of ventilation holes 141 is S4, and 0.4≤S4 / S0≤0.7 is satisfied. By using a plurality of ventilation holes 141 as the ventilation structure, and limiting the ratio between the total area S4 of the plurality of ventilation holes 141 and the effective opening area S0 of the explosion-proof valve 13, on the one hand, it is ensured that the total area S4 of the plurality of ventilation holes 141 is large enough to meet the flow rate requirement of the gas passing through the insulating member 14 when the explosion-proof valve 13 is exhausted, and on the other hand, since the insulating member 14 is responsible for limiting and fixing the electrode group 2 in addition to playing the role of insulation protection, the insulating member 14 needs to have a certain structural strength, so as to avoid the total area S4 of the plurality of ventilation holes 141 being too large, thereby reducing the structural strength of the insulating member 14, causing the insulating member 14 to be easily deformed, and making it impossible to meet the fixing and limiting functions of the electrode group 2.
[0043] The shape of the vent hole 141 provided on the insulating member 14 can be freely set according to the requirements, such as circular, polygonal or racetrack shape, etc., as long as the shape is convenient for production and realization. In the present embodiment, the vent hole 141 is in the shape of a racetrack.
[0044] Alternatively, if Figure 1 , Figure 5As shown, the spacing dimension L1 between the explosion-proof valve 13 and the pole 12 adjacent thereto along the first direction satisfies 6mm≤L1≤20mm. Since high temperature will be generated when the poles 12 are welded to each other, the explosion-proof valve 13 will be affected by the high temperature, which will cause the valve opening pressure to change, causing the valve opening pressure to deviate from the set value. Therefore, by limiting the spacing dimension L1 between the explosion-proof valve 13 and the pole 12 adjacent thereto along the first direction, the explosion-proof valve 13 is prevented from being too close to the pole 12, thereby reducing the thermal impact on the explosion-proof valve 13 when the pole ear 21 is welded to the pole 12.
[0045] Among them, the spacing dimension L1 between the explosion-proof valve 13 and the adjacent pole 12 along the first direction can be any value between 6mm and 20mm or a range between any two values, for example, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, etc.
[0046] Alternatively, if Figure 1 , Figure 4 As shown, the pole lug 21 includes a first boundary 211 formed after bending, and the spacing dimension L2 between the first boundary 211 and the adjacent flow hole 22 along the second direction satisfies 4mm≤L2≤7mm. In order to facilitate the connection between the pole lug 21 and the pole 12, the pole lug 21 needs to be bent after the pole group 2 is put into the shell, so that the pole lug 21 and the bottom surface of the pole 12 are parallel, so as to facilitate welding the two. At this time, the bent pole lug 21 will form a fold on the surface of the pole lug 21 away from the pole 12. In order to avoid the fold of the pole lug 21 from coinciding with the flow hole 22 opened on the pole lug 21, the fold formed by the bending of the pole lug 21 is set as the first boundary 211, and the spacing dimension L2 between the first boundary 211 and the adjacent flow hole 22 along the second direction is limited, so as to avoid the interference between the pole lug 21 and the flow hole 22 when the pole lug 21 is bent due to the close distance between the two.
[0047] The spacing dimension L2 between the first boundary 211 and the adjacent flow hole 22 along the second direction may be any value between 4 mm and 7 mm or a range between any two values, such as 4 mm, 5 mm, 6 mm, 7 mm, etc.
[0048] Alternatively, if Figure 1 , Figure 4As shown, the tab 21 also includes a second boundary 212 opposite to the first boundary 211 along the second direction, and the spacing dimension between the second boundary 212 and the flow hole 22 adjacent thereto along the second direction is L3, and satisfies 2mm≤L3≤3mm. Since the flow hole 22 is manufactured by die-cutting, the spacing dimension L3 between the second boundary 212 of the tab 21 and the flow hole 22 adjacent thereto along the second direction is limited, thereby reserving sufficient margin between the second boundary 212 during die-cutting, thereby ensuring smooth die-cutting process.
[0049] The spacing dimension L3 between the second boundary 212 and the adjacent flow hole 22 along the second direction may be any value between 2 mm and 3 mm or a range between any two values, such as 2 mm, 2.5 mm, 3 mm, etc.
[0050] Alternatively, if Figure 1 , Figure 4 As shown, the tab 21 also includes a third boundary 213 perpendicular to the first boundary 211 and located below the explosion-proof valve 13. The spacing dimension L4 between the third boundary 213 and the flow hole 22 adjacent thereto along the first direction satisfies 2mm≤L4≤3mm. Since the flow hole 22 is manufactured by die-cutting, the spacing dimension L4 between the third boundary 213 of the tab 21 and the flow hole 22 adjacent thereto along the first direction is limited, thereby reserving sufficient margin between the third boundary 213 during die-cutting to ensure smooth die-cutting process.
[0051] The spacing dimension L4 between the third boundary 213 and the adjacent flow hole 22 along the first direction may be any value between 2 mm and 3 mm or a range between any two values, such as 2 mm, 2.5 mm, 3 mm, etc.
[0052] Alternatively, if Figure 1 , Figure 4As shown, the projection of the flow hole 22 adjacent to the pole 12 on the cover body 11 along the third direction covers part of the explosion-proof valve 13, and the shortest length dimension of the area of the flow hole 22 adjacent to the pole 12 that does not cover the explosion-proof valve 13 along the first direction is L5, and satisfies 1mm≤L5≤7mm. In this embodiment, the explosion-proof valve 13 has an opening boundary 131. Since the projection of the flow hole 22 adjacent to the pole 12 on the cover body 11 along the third direction only covers part of the explosion-proof valve 13, it is proved that the opening boundary 131 of the explosion-proof valve 13 is located in the flow hole 22 adjacent to the pole 12. By limiting the shortest length dimension L5 of the area in the flow hole 22 adjacent to the pole 12 that does not cover the explosion-proof valve 13 along the first direction, it is avoided that the flow hole 22 adjacent to the pole 12 exceeds the opening boundary 131 by too much, thereby extending the path of air passing through the flow hole 22 and entering the explosion-proof valve 13, thereby indirectly leading to a reduction in the exhaust rate of the explosion-proof valve 13.
[0053] Among them, the distance dimension L5 of the flow hole 22 whose projection on the cover body 11 covers the opening boundary 131 beyond the opening boundary 131 along the first direction can be any value between 1mm and 7mm or a range between any two values, such as 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, etc.
[0054] In order to verify the effect of the above-mentioned relevant limitations on the battery safety test after the pole ear 21 is opened, as shown in Table 1, ten groups of embodiments and eight groups of comparative examples are provided for verification, wherein this test only discusses the relevant factors affecting the exhaust rate, namely, the ratio of the total area S1 of the plurality of flow holes 22 to the area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction, the ratio of the area S2 of the explosion-proof valve projected on the pole ear 21 along the third direction to the effective opening area S0 of the explosion-proof valve 13, the ratio of the area S3 of the exhaust area on the insulating member 14 to the effective opening area S0 of the explosion-proof valve 13, and the ratio of the total area S4 of the plurality of vents 141 to the effective opening area S0 of the explosion-proof valve 13, and the ratio of the total area S4 of the plurality of vents 141 to the effective opening area S0 of the explosion-proof valve 13, and the ratio of the total area S5 of the plurality of vents 141 to the effective opening area S0 of the explosion-proof valve 13. The die-cutting factors related to the formation of the flow hole 22 on 21 and the factors affected by the heat of the explosion-proof valve 13, namely, the spacing dimension L1 between the explosion-proof valve 13 and the adjacent pole 12 along the first direction, the spacing dimension L2 between the first boundary 211 and the adjacent flow hole 22 along the second direction, the spacing dimension L3 between the second boundary 212 and the adjacent flow hole 22 along the second direction, the spacing dimension L4 between the third boundary 213 and the adjacent flow hole 22 along the first direction, and the distance dimension L5 of the flow hole 22 whose projection on the cover body 11 covers the opening boundary 131 and exceeds the opening boundary 131 along the first direction, are not within the scope of discussion of this test, and the values set for them all meet the required ranges.
[0055] Table 1
[0056]
[0057] It can be seen from the above table that in Examples 1 to 10, the ratio of the total area S1 of the multiple flow holes 22 to the area S2 of the explosion-proof valve 13 projected onto the pole ear 21 along the third direction satisfies the range of 0.5≤S1 / S2≤0.7, the ratio of the area S2 of the explosion-proof valve 13 projected onto the pole ear 21 along the third direction to the effective opening area S0 of the explosion-proof valve 13 satisfies the range of S2 / S0≤0.5, the ratio of the area S3 of the exhaust area on the insulating member 14 to the effective opening area S0 of the explosion-proof valve 13 satisfies the range of 1.1≤S3 / S0≤1.3, and the ratio of the total area S4 of the multiple vents 141 to the effective opening area S0 of the explosion-proof valve 13 satisfies the range of 0.4≤S4 / S0≤0.7, so that the explosion-proof valve 13 has a better exhaust effect, and the passing rate after the safety test is 5 / 5, which meets the safety requirements.
[0058] As can be seen from the table above, in Comparative Example 1, the total area S1 of the plurality of flow holes 22 is 75 mm 2 The area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction is 160 mm 2 At this time, the ratio of the total area S1 of the multiple flow holes 22 and the area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction is 0.47, which is less than the minimum value in the range of 0.5≤S1 / S2≤0.7. At this time, the multiple flow holes 22 cannot fully meet the requirements of the explosion-proof valve 13 for the flow rate during exhaust, and the exhaust effect is poor. Therefore, the passing rate after the safety test is 4 / 5, and there are products that do not meet the safety requirements.
[0059] As can be seen from the table above, in Comparative Example 2, the total area S1 of the plurality of flow holes 22 is 320 mm 2 The area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction is 450mm 2 At this time, the ratio of the total area S1 of the multiple flow holes 22 and the area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction is 0.71, which is greater than the maximum value in the range of 0.5≤S1 / S2≤0.7. At this time, the multiple flow holes 22 occupy a larger area of the pole ear 21, resulting in a reduction in the area of the pole ear 21 used for flow, thereby causing the flow temperature rise to exceed the average value by about 8 degrees, which does not meet the flow demand requirements.
[0060] As can be seen from the table above, in Comparative Example 3, the area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction is 55 mm 2 , the effective opening area S0 of the explosion-proof valve 13 is 100mm 2At this time, the ratio of the area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction to the effective opening area S0 of the explosion-proof valve 13 is 0.55, which is greater than the maximum value in the range of S2 / S0≤0.5. In comparative example 4, the area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction is 550 mm 2 , the effective opening area S0 of the explosion-proof valve 13 is 1000mm 2 At this time, the ratio of the area S2 of the explosion-proof valve 13 projected on the pole ear 21 along the third direction to the effective opening area S0 of the explosion-proof valve 13 is 0.55, which is greater than the maximum value of S2 / S0≤0.5. Therefore, in Comparative Examples 3 and 4, the area of the explosion-proof valve 13 blocked by the pole ear 21 is too large, which affects the circulation of pressurized gas when the explosion-proof valve 13 is exhausted, and the exhaust effect is poor. Therefore, the passing rate after the safety test is 3 / 5, and there are products that do not meet the safety requirements.
[0061] As can be seen from the table above, in Comparative Example 5, the area S3 of the exhaust region on the insulating member 14 is 105 mm 2 , the effective opening area S0 of the explosion-proof valve 13 is 100mm 2 At this time, the ratio of the area S3 of the exhaust region on the insulating member 14 to the effective opening area S0 of the explosion-proof valve 13 is 1.05, which is less than the minimum value in the range of 1.1≤S3 / S0≤1.3, resulting in the area on the insulating member 14 for opening the ventilation structure being too small, thereby failing to fully meet the requirements of the explosion-proof valve 13 for the flow rate passing through the insulating member 14 during exhaust, and the exhaust effect is poor. Therefore, the passing rate after the safety test is 4 / 5, and there are products that do not meet the safety requirements.
[0062] As can be seen from the table above, in Comparative Example 6, the area S3 of the exhaust region on the insulating member 14 is 1350 mm 2 , the effective opening area S0 of the explosion-proof valve 13 is 1000mm 2 At this time, the ratio of the area S3 of the exhaust region on the insulating member 14 to the effective opening area S0 of the explosion-proof valve 13 is 1.35, which is greater than the maximum value in the range of 1.1≤S3 / S0≤1.3, resulting in an area on the insulating member 14 for opening the ventilation structure being too large, resulting in a low strength of the insulating member 14, causing deformation, and failing to effectively fix and support the pole group 2.
[0063] As can be seen from the table above, in Comparative Example 7, the total area S4 of the plurality of vent holes 141 is 35 mm 2 , the effective opening area S0 of the explosion-proof valve 13 is 100mm 2The ratio of the total area S4 of the multiple vents 141 to the effective opening area S0 of the explosion-proof valve 13 is 0.35, which is less than the minimum value in the range of 0.4≤S4 / S0≤0.7. At this time, the multiple vents 141 cannot fully meet the flow rate requirements of the explosion-proof valve 13 during exhaust, and the exhaust effect is poor. Therefore, the passing rate after the safety test is 2 / 5, and there are products that do not meet the safety requirements.
[0064] As can be seen from the above table, in Comparative Example 8, the total area S4 of the plurality of vent holes 141 is 750 mm 2 , the effective opening area S0 of the explosion-proof valve 13 is 1000mm 2 The ratio of the total area S4 of the plurality of vent holes 141 to the effective opening area S0 of the explosion-proof valve 13 is 0.75, which is greater than the maximum value in the range of 0.4≤S4 / S0≤0.7, resulting in low strength of the insulating member 14, causing deformation, and being unable to effectively fix and support the pole group 2.
[0065] In this embodiment, a battery pack is also provided, which includes a battery pack box and the above-mentioned battery, wherein a plurality of batteries are arranged in the battery pack box. By using the above-mentioned battery, the battery pack has higher use safety, improves structural reliability, and optimizes product quality.
[0066] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.
Claims
1. A battery, characterized in that The battery comprises: A cover plate assembly, the cover plate assembly comprising a cover plate body, a pole and an explosion-proof valve, wherein the pole and the explosion-proof valve are both arranged on the cover plate body; A pole group, the pole group comprising a pole lug, the pole lug being bent and welded to the pole column; A plurality of flow holes are provided on the pole ear, the total area of the plurality of flow holes is S1, the area of the explosion-proof valve projected on the pole ear along the third direction is S2, and 0.5≤S1 / S2≤0.7 is satisfied.
2. The battery according to claim 1, characterized in that The effective opening area of the explosion-proof valve is S0, and satisfies S2 / S0≤0.
5.
3. The battery according to claim 2, characterized in that The cover plate assembly also includes an insulating member, which is arranged between the cover plate body and the pole group. A ventilation area corresponding to the explosion-proof valve is provided on the insulating member. A ventilation structure connected to the explosion-proof valve is provided in the ventilation area. The area of the ventilation area is S3, and satisfies 1.1≤S3 / S0≤1.
3.
4. The battery according to claim 3, characterized in that The ventilation structure is a plurality of ventilation holes, the total area of the plurality of ventilation holes is S4, and 0.4≤S4 / S0≤0.7 is satisfied.
5. The battery according to claim 1, characterized in that The distance between the explosion-proof valve and the pole adjacent thereto along the first direction is L1, and satisfies 6mm≤L1≤20mm.
6. The battery according to claim 1, characterized in that The electrode tab includes a first boundary formed by bending, and a spacing dimension between the first boundary and the adjacent flow hole along the second direction is L2, and satisfies 4mm≤L2≤7mm.
7. The battery according to claim 6, characterized in that The electrode tab further includes a second boundary opposite to the first boundary along the second direction, and a spacing dimension between the second boundary and the adjacent flow hole along the second direction is L3, and satisfies 2mm≤L3≤3mm.
8. The battery according to claim 6, characterized in that The electrode ear also includes a third boundary perpendicular to the first boundary and located below the explosion-proof valve. The spacing dimension between the third boundary and the adjacent flow hole along the first direction is L4, and satisfies 2mm≤L4≤3mm.
9. The battery according to claim 1, characterized in that The projection of the flow hole adjacent to the pole on the cover body along the third direction covers part of the explosion-proof valve, and the shortest length dimension of the area of the flow hole adjacent to the pole that does not cover the explosion-proof valve along the first direction is L5, and satisfies 1mm≤L5≤7mm.
10. A battery pack, characterized in that: The battery pack comprises a battery pack case and a battery as described in any one of claims 1 to 9, and a plurality of the batteries are disposed in the battery pack case.