Battery, battery pack and electric equipment

Abstract

The utility model relates to the technical field of batteries, and discloses a battery, a battery pack and electric equipment. The battery comprises a body, an exhaust hole is formed in the body, and a containing groove is further formed in the area, corresponding to the exhaust hole, of the body; the anti-explosion valve is arranged in the containing groove; in the plane parallel to the body, the minimum distance between a welding mark formed by welding the anti-explosion valve and the containing groove and the edge of the body is f, and f is larger than or equal to 4 mm. According to the battery provided by the invention, the minimum distance between the welding mark formed by welding the explosion-proof valve and the accommodating groove and the edge of the body is greater than or equal to 4mm, so that the influence on the explosion-proof valve in a battery manufacturing process, such as operations of welding the periphery of a shell cover and the like, can be reduced, the stress balance of the explosion-proof valve is ensured, and the influence on the explosion-proof valve caused by external force is reduced; and the opening condition of the anti-explosion valve is accurate and controllable.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 2024101011331, filed January 25, 2024, entitled “A Battery, Battery Pack and Electrical Device”; Chinese Patent Application No. 2024101548765, filed February 4, 2024, entitled “Battery”; and Chinese Patent Application No. 2024101671825, filed February 6, 2024, entitled “Explosion-proof Valve and Battery”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of battery technology, specifically to batteries, battery packs, and electrical equipment. Background Technology

[0004] With the continuous development of the battery industry, lithium-ion batteries, with their high energy density, are widely used in the field of power batteries to provide power for vehicle operation. Explosion-proof valves play a crucial role in the safety of battery cells. When problems such as short circuits, overcharging, or overheating occur in the battery cell, the explosion-proof valve senses changes in the internal air pressure of the cell and opens in a timely manner to release pressure and prevent risks such as cell explosions or fires.

[0005] However, because explosion-proof valves need to meet the requirements of precise and controllable opening, some explosion-proof valves in the existing technology cannot be adapted to the battery cell manufacturing process, resulting in uncontrollable opening and posing safety hazards. Utility Model Content

[0006] In view of this, this application provides a battery, a battery pack, and an electrical device to solve the safety hazard caused by the inability of explosion-proof valves to meet the requirements of precise and controllable opening.

[0007] In a first aspect, this application provides a battery comprising:

[0008] The body has an exhaust hole, and a receiving groove is formed in the area of ​​the body corresponding to the exhaust hole.

[0009] An explosion-proof valve is installed inside the receiving groove;

[0010] On a plane parallel to the body, the minimum distance between the weld mark formed by welding the explosion-proof valve and the receiving groove and the edge of the body is f, and f≥4mm.

[0011] The explosion-proof valve includes: a grooved surface and an overlapping portion surrounding the circumferential edge of the grooved surface; at least a portion of the grooved surface near the overlapping portion is recessed to form peripheral grooves;

[0012] In a plane perpendicular to the body, the projection of the peripheral groove is located within the projection range of the vent hole; and in a plane parallel to the body, the minimum distance between the edge of the peripheral groove and the vent hole on the edge of the body is c, and satisfies: 1mm≤c≤3mm;

[0013] In the direction perpendicular to the overlapping portion, the height difference between the groove surface and the overlapping portion is d1, and satisfies 0.15mm≤d1≤0.2mm;

[0014] The groove surface is also formed with reinforcing rib markings, which are located on the side of the peripheral markings away from the overlapping portion. In the direction perpendicular to the groove surface, the projections of the reinforcing rib markings and the peripheral markings do not overlap. In the direction perpendicular to the groove surface, the residual thickness of the peripheral markings is d2, and the residual thickness of the reinforcing rib markings is d3, satisfying: 120μm≤d3≤180μm; 30μm≤d3-d2≤100μm.

[0015] The dimensions of the battery satisfy the following conditions: the battery length ranges from 100mm to 600mm, the battery width ranges from 50mm to 250mm, and the battery height ranges from 10mm to 100mm; or, the dimensions of the battery satisfy the following conditions: the battery length ranges from 600mm to 1500mm, the battery width ranges from 50mm to 250mm, and the battery height ranges from 10mm to 100mm.

[0016] When the battery cell material is lithium iron phosphate, the burst pressure range of the explosion-proof valve is 0.4 MPa-0.8 MPa.

[0017] When the battery cell material is ternary lithium, the burst pressure range of the explosion-proof valve is 0.7 MPa-1.2 MPa.

[0018] When the battery cell material is a cobalt-free system, the burst pressure range of the explosion-proof valve is 0.8 MPa-1.2 MPa;

[0019] When the battery cell material is sodium, the burst pressure range of the explosion-proof valve is 0.7 MPa to 1.1 MPa.

[0020] When the battery cell is a semi-solid-state battery or an all-solid-state battery, the burst pressure range of the explosion-proof valve is 0.7 MPa to 1.2 MPa.

[0021] Beneficial effects: The battery provided in the embodiments of this application reduces the impact of the battery manufacturing process on the explosion-proof valve by ensuring that the minimum distance between the weld mark formed by welding the explosion-proof valve and the receiving groove and the edge of the body is greater than or equal to 4mm. For example, operations such as welding around the shell cover can reduce the impact of the explosion-proof valve on the explosion-proof valve. This ensures the balanced force on the explosion-proof valve, reduces the impact of external forces on the explosion-proof valve, and makes the opening conditions of the explosion-proof valve precise and controllable.

[0022] Furthermore, by forming peripheral grooves in at least a portion of the groove surface near the overlap, and by forming reinforcing rib grooves on the side of the groove surface away from the overlap, and by making the residual thickness d2 of the peripheral grooves smaller than the residual thickness d3 of the reinforcing rib grooves, it can be ensured that the explosion-proof valve will preferentially burst through the path defined by the peripheral grooves in the event of thermal runaway, thereby ensuring the exhaust area of ​​the explosion-proof valve. Simultaneously, the reinforcing rib grooves can enhance the structural strength of the groove surface and reduce the deformation of the groove surface under normal use.

[0023] Furthermore, since the projection of the peripheral grooves lies within the projection range of the vent hole, interference between the vent hole and the opening area of ​​the groove surface can be avoided when the explosion-proof valve opens along the peripheral grooves. By limiting the lower limit of the minimum distance c between the edge of the peripheral grooves and the edge of the vent hole on the plane parallel to the body, interference between the vent hole and the opening area of ​​the groove surface can be avoided. And by limiting the upper limit of the minimum distance c between the edge of the peripheral grooves and the edge of the vent hole on the plane of the body, sufficient opening area of ​​the explosion-proof valve can be ensured, preventing the vent hole opening from being too large.

[0024] Furthermore, by limiting the lower limit of the height difference d1 between the groove surface and the overlap, the smooth opening of the explosion-proof valve can be ensured, avoiding opening difficulties caused by an excessively thick groove surface. Simultaneously, the welding requirements between the overlap and the main body are met, avoiding welding difficulties caused by an excessively thin overlap. At the same time, by limiting the upper limit of the height difference d1 between the groove surface and the overlap, material accumulation at the overlap can be avoided due to excessive differences between the two planes, preventing excessive density from affecting product performance.

[0025] In one optional embodiment, the depth of the receiving groove is D3 in a plane perpendicular to the body, and the thickness of the overlap portion of the explosion-proof valve is D4; the explosion-proof valve is received in the receiving groove, and satisfies: 0mm≤D3-D4≤0.2mm;

[0026] The value range of D4 is 0.4mm≤D4≤0.6mm; the value range of D3 is 0.5mm≤D3≤0.6mm.

[0027] Beneficial effects: By making the depth D3 of the receiving groove greater than the thickness D4 of the overlap of the explosion-proof valve, it can be ensured that the receiving groove completely accommodates the explosion-proof valve, ensuring smooth assembly and welding of the explosion-proof valve and the light aluminum plate. If the height difference between the two is less than 0mm, the explosion-proof valve is likely to protrude from the body, which can easily cause wear to the explosion-proof valve. If the height difference between the two is greater than 0.2mm, it is easy to cause poor welding when welding the explosion-proof valve to the body.

[0028] In one optional embodiment, the residual thickness d2 of the peripheral groove is in the range of 60μm≤d2≤180μm; the peripheral groove is continuously provided on the outer periphery of the groove surface.

[0029] In one optional embodiment, the interior of the body is enclosed to form a sealed cavity, and an electrode assembly is disposed within the sealed cavity;

[0030] The peripheral groove formed by the recessed groove surface is formed by the side of the groove surface away from the electrode group and recessed towards the electrode group;

[0031] Alternatively, the peripheral grooves formed by the recessed groove surface are formed by the recessed side of the groove surface near the electrode group in a direction away from the electrode group.

[0032] In one alternative embodiment, the reinforcing rib groove is formed by recessing the groove surface.

[0033] Beneficial effects: By making the reinforcing rib grooves recessed from the groove surface, the need for strengthening the groove surface structure can be met, while reducing the overall weight of the explosion-proof valve and increasing the energy density.

[0034] In one optional embodiment, the reinforcing rib groove includes at least two arc-shaped grooves, the two ends of which intersect with the peripheral grooves, and at least two arc-shaped grooves partially overlap to form a groove overlap area.

[0035] Alternatively, the reinforcing rib grooves include at least two arc-shaped grooves, the two ends of which intersect with the peripheral grooves, and the at least two arc-shaped grooves do not overlap with each other;

[0036] Alternatively, the reinforcing rib groove is constructed as a Y-shaped groove, with at least one end of the Y-shaped groove intersecting the peripheral groove;

[0037] Alternatively, the reinforcing rib groove is constructed as a zigzag groove, with at least one end of the zigzag groove intersecting with the peripheral groove;

[0038] Alternatively, the reinforcing rib grooves may be constructed as multiple straight grooves, and these multiple straight grooves may not be connected to the surrounding grooves, and the multiple straight grooves may not intersect each other;

[0039] The reinforcing rib groove is located in the central area of ​​the groove surface;

[0040] The reinforcing rib grooves are symmetrically arranged along the central axis of the explosion-proof valve along its length, and / or the reinforcing rib grooves are symmetrically arranged along the central axis of the explosion-proof valve along its width.

[0041] Beneficial effects: By forming the reinforcing rib grooves at the intersection of two reinforcing rib grooves, the most easily deformed area in the middle of the groove surface can be reinforced, reducing the amount of deformation.

[0042] In one optional embodiment, the body includes a plurality of plates and an electrode assembly, the plurality of plates being interconnected to form a sealed cavity, and the electrode assembly being disposed within the sealed cavity;

[0043] At least one of the plates has the vent holes and the receiving grooves arranged and communicating with each other along a second direction; the explosion-proof valve is connected to the plate and covers the vent holes;

[0044] Wherein, along the first direction, the receiving groove has a first dimension D1, and the explosion-proof valve has a second dimension D2, satisfying: 0.02mm≤(D1-D2) / 2≤0.2mm;

[0045] The overlapping portion is connected to the plate;

[0046] Along the first direction, the peripheral groove has a certain width, and there is a first distance L2 between the edge of the peripheral groove near the overlapping part and the edge of the overlapping part near the peripheral groove, satisfying: 0.3mm≤L2≤3mm;

[0047] Along the first direction, the vent has a fifth dimension D5, satisfying: 0.25mm≤(D1-D5) / 2≤2.5mm;

[0048] Along the first direction, the overlapping portion has a sixth dimension D6, and the second dimension D2, the fifth dimension D5, the sixth dimension D6 and the first spacing L2 satisfy: 0.5mm≤D5-[D2-(D6+L2)×2]≤5mm;

[0049] The first dimension D1 satisfies: 5mm≤D1≤70mm; or, the second dimension D2 satisfies: 5mm≤D2≤70mm;

[0050] The plate has two first surfaces arranged opposite to each other along the first direction, and the two first surfaces are used to enclose and form the receiving groove;

[0051] The plate also includes two side surfaces that are opposite to each other along the first direction, with the two first surfaces located between the two side surfaces; wherein, along the first direction, the side surface and the first surface have a minimum dimension L1 that satisfies: 2mm≤L1≤25mm.

[0052] Beneficial effects: By setting vent holes and receiving slots in the battery panel, as well as explosion-proof valves that cooperate with the receiving slots, and further improving the dimensions of the mutual cooperation between the explosion-proof valve and the panel, the overall structural strength of the explosion-proof valve and the battery is reliably improved, ensuring a good fit between the explosion-proof valve and the battery as a whole, and enhancing the safe use performance of the battery.

[0053] Furthermore, when the first spacing L2 meets the above-mentioned value range, the peripheral grooves of the explosion-proof valve are less likely to deform and fail due to the heat effect of welding, and are not too large, thus reducing the effective usable area of ​​the explosion-proof valve. Moreover, when the values ​​of D1 and D5 meet the above-mentioned value range, the stability of the connection between the explosion-proof valve and the plate can be guaranteed.

[0054] Furthermore, a second spacing L3 is set, L3 = D5[D2(D6+L2)×2], and the second spacing L3 satisfies: 0.5mm≤L3≤5mm, which can ensure that the peripheral groove on the explosion-proof valve is located inside the vent hole, so as to meet the requirement that the explosion-proof valve can open normally and complete the pressure relief when thermal runaway occurs.

[0055] When the minimum dimension L1 between the side and the first surface meets the above value range, it can ensure the overall strength of the plate and avoid the local high temperature generated during battery casing and battery welding from having a thermal effect on the explosion-proof valve, which may cause deformation or even cracking failure.

[0056] In one alternative embodiment, along the second direction, the receiving groove has a third dimension D3, and the overlapping portion has a fourth dimension D4, satisfying: 0.02mm≤D3-D4≤0.2mm;

[0057] The third dimension D3 satisfies: 0.3mm≤D3≤2mm; or the fourth dimension D4 satisfies: 0.3mm≤D4≤2mm.

[0058] Beneficial effects: When the values ​​of D3 and D4 meet the above range, it can avoid the problem of excessive height difference when assembling the explosion-proof valve into the receiving groove, and at the same time avoid problems such as pores or uneven welds when welding the explosion-proof valve and the plate.

[0059] When the value of D3 meets the above range, it can ensure the welding strength of the explosion-proof valve and the plate, and meet the requirement of sufficient height to accommodate the welding penetration depth, so as to ensure the stable connection of the formed explosion-proof valve and the plate.

[0060] Secondly, this application also provides a battery pack including the aforementioned battery.

[0061] Thirdly, this application also provides an electrical device including the aforementioned battery pack. Attached Figure Description

[0062] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0063] Figure 1 This is a top view of the battery in this application;

[0064] Figure 2 For the battery Figure 1 A schematic diagram under the AA section view;

[0065] Figure 3 for Figure 2 Enlarged view of point B in the middle;

[0066] Figure 4 This is a schematic diagram of the explosion-proof valve of this application;

[0067] Figure 5 for Figure 4 A schematic diagram of the CC section;

[0068] Figure 6 for Figure 5 Enlarged view of point D in the middle;

[0069] Figure 7 for Figure 5 Enlarged view of point E in the middle;

[0070] Figure 8 This is a three-dimensional schematic diagram of the explosion-proof valve formed on the battery cover plate in this application;

[0071] Figure 9 This is a schematic diagram showing the partial explosion-proof valve of the battery cover in this application.

[0072] Figure 10 This is a schematic diagram of another explosion-proof valve according to this application;

[0073] Figure 11 This is a schematic diagram of yet another explosion-proof valve according to this application;

[0074] Figure 12 This is a schematic diagram of another explosion-proof valve according to this application;

[0075] Figure 13This is a schematic diagram of an additional explosion-proof valve according to this application;

[0076] Figure 14 For the battery in this application Figure 1 A schematic diagram of the fit between the FF cross-section view and the housing;

[0077] Figure 15 For another type of battery in this application Figure 1 A schematic diagram of the fit between the FF cross-section view and the housing;

[0078] Figure 16 This application provides another type of battery in Figure 1 A schematic diagram of the fit between the FF cross-section view and the housing;

[0079] Figure 17 This is an example diagram of the explosion-proof valve of this application after it bursts open along the peripheral grooves;

[0080] Figure 18 This is an example diagram showing that part of the explosion-proof valve of this application is burst open along the peripheral grooves, while another part is connected to the overlapping part through the compaction part;

[0081] Figure 19 This is a schematic diagram of the structure of a plate component in a battery according to this application;

[0082] Figure 20 This is a partial structural diagram of a plate component in a battery according to this application;

[0083] Figure 21 This is a cross-sectional structural diagram of a plate component in a battery according to this application;

[0084] Figure 22 This is a schematic diagram of the structure of another plate component in the battery according to this application;

[0085] Figure 23 This is a partial structural diagram of a plate component in another battery according to this application;

[0086] Figure 24 This is a cross-sectional structural diagram of another plate component in a battery according to this application;

[0087] Figure 25 This is a cross-sectional structural diagram of a plate component in another type of battery according to this application;

[0088] Figure 26 for Figure 25 Enlarged diagram of point G in the middle;

[0089] Figure 27 This is a cross-sectional structural diagram of an explosion-proof valve in a battery according to this application;

[0090] Figure 28 for Figure 27Enlarged view of point H in the middle;

[0091] Figure 29 This is a schematic diagram showing the battery casing cracking after a safety test, which is provided as a comparative example of this application.

[0092] Explanation of reference numerals in the attached figures:

[0093] 1. Body; 11. Vent hole; 12. Plate; 121. First surface; 122. Side; 13. Receiving groove; 2. Explosion-proof valve; 21. Overlapping edge; 22. Peripheral groove; 23. Groove surface; 24. Overlapping groove area; 25. Reinforcing rib groove; 26. Compacted part; 3. Shell. Detailed Implementation

[0094] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0095] The following is combined Figures 1 to 9 This describes an embodiment of the present application.

[0096] According to an embodiment of this application, a battery is provided, comprising:

[0097] The main body 1 has an exhaust hole 11, and a receiving groove 13 is formed in the area of ​​the main body 1 corresponding to the exhaust hole 11.

[0098] Explosion-proof valve 2 is installed in receiving tank 13;

[0099] On the plane parallel to the body 1, the minimum distance between the weld mark formed by welding the explosion-proof valve 2 and the receiving groove 13 and the edge of the body 1 is f, and f ≥ 4 mm.

[0100] The receiving groove 13 is suitable for accommodating the explosion-proof valve 2, and is sealed to the body 1 by welding the overlapping part 21.

[0101] The battery provided in the embodiments of this application reduces the impact of the battery manufacturing process on the explosion-proof valve 2 by ensuring that the minimum distance between the weld mark formed by welding the explosion-proof valve 2 and the receiving groove 13 and the edge of the body 1 is greater than or equal to 4mm. For example, operations such as welding around the shell cover can reduce the impact of the battery manufacturing process on the explosion-proof valve 2. This ensures that the explosion-proof valve 2 is subjected to balanced forces, reduces the impact of external forces on the explosion-proof valve 2, and makes the opening conditions of the explosion-proof valve 2 precise and controllable.

[0102] In this embodiment, the body 1 may include a battery cover and a housing 3.

[0103] Optional, combined Figure 3 As shown, the thickness a0 of the shell 3 ranges from 1.0mm ≤ a0 ≤ 1.5mm. To meet the requirements for welding and the strength of the shell 3, the depth D3 of the corresponding fitting groove 13 ranges from 0.5mm ≤ D3 ≤ 0.6mm.

[0104] In other embodiments, combined with Figure 8 As shown, a vent 11 is provided on the battery casing 3, and a receiving groove 13 is formed in the area of ​​the casing 3 corresponding to the vent 11. The explosion-proof valve 2 is fixedly connected to the casing 3. It should be noted that the vent 11 can be provided on the battery casing 3 or on the battery itself. Correspondingly, the explosion-proof valve 2 can be provided on the battery casing 3 or on the battery itself, as long as the venting and pressure relief requirements are met.

[0105] In some embodiments, combined with Figures 3 to 7 as well as Figures 10 to 13 The explosion-proof valve 2 shown includes:

[0106] The grooved surface 23 and the overlapping portion 21 surrounding the circumferential edge of the grooved surface 23;

[0107] At least a portion of the grooved surface 23 near the overlapping edge 21 is recessed to form peripheral grooves 22;

[0108] The groove surface 23 is also formed with reinforcing rib marks 25. The reinforcing rib marks 25 are located on the side of the peripheral marks 22 away from the overlapping portion 21, and in the direction perpendicular to the groove surface 23, the reinforcing rib marks 25 do not overlap with the projection of the peripheral marks 22 at least partially.

[0109] In the direction perpendicular to the groove surface 23, the remaining thickness of the peripheral groove 22 is d2, and the remaining thickness of the reinforcing rib groove 25 is d3, satisfying: 30μm≤d3-d2≤100μm.

[0110] In this embodiment, the thickness of the grooved surface 23 is less than the thickness of the overlapping portion 21. The overlapping portion 21 is used for welding to the body 1 to fix the explosion-proof valve 2 onto the body 1. The overlapping portion 21, by having a larger thickness, can meet the welding requirements. The grooved surface 23, by having a smaller thickness, can ensure the sealing requirements of the battery under normal use, and on the other hand, can ensure smooth bursting under pressure, facilitating venting.

[0111] By recessing at least a portion of the groove surface 23 near the overlap portion 21 to form peripheral grooves 22, the local thinning of peripheral grooves 22 can form a path guide for opening the groove surface 23, making it convenient for the explosion-proof valve 2 to open according to the path of peripheral grooves 22.

[0112] Combination Figure 17 and Figure 18 As shown, the explosion-proof valve 2 can burst open along the peripheral grooves 22, using the guide path formed by the peripheral grooves 22 as the opening path. After opening, it ensures a sufficiently large opening area to guarantee the venting area of ​​the explosion-proof valve 2. Simultaneously, by ensuring that the minimum distance between the weld mark formed by welding the explosion-proof valve 2 to the edge of the body 1 is greater than or equal to 4mm, the impact of the battery manufacturing process on the explosion-proof valve 2 can be reduced, thereby ensuring the balanced force on the explosion-proof valve 2, reducing the impact of external forces on the explosion-proof valve 2, and making the opening conditions of the explosion-proof valve 2 precisely controllable. Combined with... Figure 17 It can be seen that after opening, there are fewer burrs on the opening path formed by the original surrounding engravings 22, and the opening is relatively smooth.

[0113] Since the groove surface 23 is thin and has a large area, the reinforcing ribs 25 are also formed on the groove surface 23. The reinforcing ribs 25 are located on the side of the peripheral ribs 22 away from the overlap 21. This can enhance the structural strength of the groove surface 23, reduce the deformation of the groove surface 23 in normal use, and ensure structural strength.

[0114] The explosion-proof valve 2 provided in the embodiments of this application has peripheral grooves 22 recessed in at least a portion of the groove surface 23 near the overlap portion 21, and reinforcing rib grooves 25 formed on the side of the groove surface 23 away from the overlap portion 21. By making the residual thickness d2 of the peripheral grooves 22 smaller than the residual thickness d3 of the reinforcing rib grooves 25, it can be ensured that the explosion-proof valve 2 will preferentially burst open from the path defined by the peripheral grooves 22 in the event of thermal runaway, thereby ensuring the exhaust area of ​​the explosion-proof valve 2. At the same time, the reinforcing rib grooves 25 can enhance the structural strength of the groove surface 23 and reduce the deformation of the groove surface 23 under normal use.

[0115] Furthermore, by limiting the upper and lower limits of the difference between the residual thickness d3 of the reinforcing rib notch 25 and the residual thickness d2 of the surrounding notch 22, the opening conditions of the explosion-proof valve 2 can be precisely controlled, adapted to the battery manufacturing process, meet the opening requirements of specific working conditions, improve safety, avoid premature opening of the explosion-proof valve 2 when the pressure is low, and avoid excessive injection pressure caused by the delayed opening of the explosion-proof valve 2 when the pressure is too high.

[0116] Optionally, the peripheral groove 22 surrounds the groove surface 23 near the edge 21, so that when the explosion-proof valve 2 opens along the peripheral groove 22, it can ensure that the explosion-proof valve 2 opens with a sufficient exhaust area.

[0117] If the remaining thickness d2 of the peripheral groove 22 is greater than the remaining thickness d3 of the reinforcing rib groove 25, the position of the reinforcing rib groove 25 is likely to be a weak point under stress, causing the explosion-proof valve 2 to open along the path of the reinforcing rib groove 25, resulting in a small opening area and the reinforcing rib groove 25 failing to effectively play a reinforcing role.

[0118] In some embodiments, combined with Figure 6 , Figure 7 As shown, the residual thickness d2 of the peripheral scratch 22 ranges from 60μm to 180μm.

[0119] The range of the residual thickness d3 of the reinforcing rib notch 25 is: 120μm≤d3≤180μm.

[0120] Optionally, the residual thickness d2 of the peripheral notch 22 can be 60μm, 70μm, 90μm, 140μm, 160μm, 170μm, or 180μm, etc.

[0121] Optionally, the residual thickness d3 of the reinforcing rib notch 25 can be 120μm, 140μm, 160μm, 170μm, or 180μm, etc.

[0122] In some embodiments, combined with Figure 14 As shown, the receiving groove 13 formed on the body 1 is formed by the recess of the side of the body 1 close to the pole group, and the peripheral groove 22 formed by the recess of the groove surface 23 is formed by the recess of the groove surface 23 away from the pole group towards the pole group.

[0123] In other embodiments, combined with Figure 15 As shown, the receiving groove 13 formed on the body 1 is formed by the recess of the side of the body 1 away from the electrode group, and the peripheral groove 22 formed by the recess of the groove surface 23 is formed by the recess of the groove surface 23 near the electrode group towards the direction away from the electrode group.

[0124] In other embodiments, combined with Figure 16 As shown, the receiving groove 13 formed on the body 1 is formed by the recess of the side of the body 1 away from the electrode group, and the peripheral groove 22 formed by the recess of the groove surface 23 is formed by the recess of the groove surface 23 towards the electrode group.

[0125] The explosion-proof valve 2 with the peripheral grooves 22 can be installed facing inwards towards the housing 3; alternatively, it can also be installed facing outwards towards the housing 3. When installed with the grooves facing inwards, external contact can effectively prevent damage to the grooves, but there is a risk of electrolyte corrosion leading to a decrease in detonation pressure (it is worth noting that the electrolyte only produces hydrofluoric acid (HF) in a water-based environment, and HF can corrode the residual material). When installed with the grooves facing outwards, electrolyte corrosion can be avoided, but there is a risk of interference with the grooved surface, requiring an additional protective plate. This introduces a bottom flatness issue, resulting in an uneven bottom of the battery.

[0126] It is understandable that the effective opening area of ​​the explosion-proof valve 2 is the area defined by the internal region of the peripheral notch 22.

[0127] In some embodiments, the reinforcing rib notch 25 is formed by recessing the groove surface 23.

[0128] By making the reinforcing rib groove 25 recessed from the groove surface 23, the need for strengthening the structure of the groove surface 23 can be met, while reducing the overall weight of the explosion-proof valve 2 and increasing the energy density.

[0129] As a variation, the reinforcing rib notch 25 can also be formed by a partial protrusion of the groove surface 23.

[0130] In some embodiments, combined with Figure 4 As shown, the reinforcing rib notch 25 includes at least two arc-shaped notches, the two ends of which intersect with the surrounding notches 22, and at least two arc-shaped notches partially overlap to form a notch overlap area 24.

[0131] In this embodiment, the two ends of the reinforcing rib groove 25 are taken as the starting point at the intersection of the straight segment and the arc segment of the racetrack-shaped structure. Two reinforcing rib grooves 25 are formed on the groove surface 23, and the two reinforcing rib grooves 25 are symmetrically arranged with respect to the central axis of the explosion-proof valve 2 along the length direction.

[0132] By forming the overlapping area 24 of the grooves at the junction of the two reinforcing rib grooves 25, the area in the middle of the groove surface 23 that is most prone to deformation can be reinforced, thereby reducing the amount of deformation.

[0133] In other embodiments, combined with Figure 10 As shown, the reinforcing rib notch 25 includes two arc-shaped notches, the two ends of which intersect with the surrounding notches 22, and the two arc-shaped notches have no overlapping area.

[0134] In other embodiments, combined with Figure 11 As shown, the reinforcing rib notch 25 is constructed as a Y-shaped notch, and at least one end of the Y-shaped notch intersects with the surrounding notch 22; combined with Figure 12 As shown, the reinforcing rib notch 25 is constructed as a zigzag notch, and at least one end of the zigzag notch intersects with the surrounding notch 22.

[0135] In other embodiments, combined with Figure 13 As shown, the reinforcing rib groove 25 is constructed as multiple straight grooves, and these multiple straight grooves are not connected to the surrounding grooves 22, nor do they intersect each other.

[0136] As a variation, the reinforcing rib notch 25 can also be constructed into other structural forms.

[0137] In some embodiments, the reinforcing rib notch 25 is located in the central region of the groove surface 23.

[0138] Furthermore, the reinforcing rib grooves 25 are symmetrically arranged along the central axis of the explosion-proof valve 2 in the length direction, and / or, the reinforcing rib grooves 25 are symmetrically arranged along the central axis of the explosion-proof valve 2 in the width direction.

[0139] In some embodiments, combined with Figure 3 As shown, in the plane perpendicular to the body 1, the depth of the receiving groove 13 is D3, and the thickness of the overlapping part 21 of the explosion-proof valve 2 is D4; the explosion-proof valve 2 is received in the receiving groove 13 and satisfies: 0mm≤D3-D4≤0.2mm;

[0140] The value of D3 is in the range of 0.5mm≤D3≤0.6mm.

[0141] By making the depth D3 of the receiving groove 13 greater than the thickness D4 of the overlap 21 of the explosion-proof valve 2, it can be ensured that the receiving groove 13 can completely accommodate the explosion-proof valve 2, and that the explosion-proof valve 2 can be smoothly assembled and welded to the aluminum plate. If the height difference between the two is less than 0 mm, the explosion-proof valve 2 may protrude from the body 1, which may cause wear to the explosion-proof valve 2. If the height difference between the two is greater than 0.2 mm, it may cause poor welding when the explosion-proof valve 2 is welded to the body 1.

[0142] In this embodiment, the thickness D4 of the overlap portion 21 of the explosion-proof valve 2 can be in the range of 0.4mm≤D5≤0.6mm.

[0143] In the direction parallel to the groove surface 23, the width D6 of the overlap 21 is in the range of 2mm≤D6≤3mm. If it is less than 2mm, it will be not conducive to the stamping of the explosion-proof valve 2 and subsequent welding with the aluminum plate. If it is greater than 3mm, it will cause a waste of area, and the effective opening area of ​​the explosion-proof valve 2 will be lost within the limited area of ​​the explosion-proof valve 2.

[0144] In some embodiments, combined with Figure 6 As shown, in the direction perpendicular to the overlap portion 21, the height difference between the groove surface 23 and the overlap portion 21 is d1, and satisfies 0.15mm≤d1≤0.2mm.

[0145] With a fixed battery cover thickness, if d1 is too thick, the valve opening pressure will be too low, causing the explosion-proof valve 2 to fail; conversely, if d1 is too thin, the valve opening pressure will be too high, preventing successful opening under the preset pressure and posing a safety hazard. By limiting the lower limit of the height difference d1 between the groove surface 23 and the overlapping portion 21, the smooth opening of the explosion-proof valve 2 can be ensured, avoiding opening difficulties caused by an excessively thick groove surface 23. Simultaneously, the welding requirements between the overlapping portion 21 and the body 1 are met, avoiding welding difficulties caused by an excessively thin overlapping portion 21. Furthermore, by limiting the upper limit of the height difference d1 between the groove surface 23 and the overlapping portion 21, material accumulation in the overlapping portion 21 caused by excessive differences between the two planes can be avoided, preventing excessive density from affecting product performance.

[0146] Optionally, the height difference d1 between the groove surface 23 and the overlapping edge 21 can be 0.15mm, 0.16mm, 0.17mm, 0.18mm, or 0.19mm, etc.

[0147] As shown in Examples 1 and 2 in Table 1 below, when the value of d1 is within the range of 0.15mm≤d1≤0.2mm, the explosion-proof valve 2 can be opened smoothly and the opening pressure is stable, effectively ensuring the accuracy of the opening pressure.

[0148] As shown in Comparative Example 1 in Table 1 below, if d1 is too small, when the thickness of the overlap 21 is constant, the thickness of the air-bearing surface will be too large, making it difficult to process the grooves, causing the opening pressure to exceed the upper limit, resulting in unstable opening and failure to vent air in time, which poses a significant safety hazard.

[0149] As shown in Comparative Example 2 in Table 1, if d1 is too large, the thickness of the gas-bearing surface will be too low, the residual thickness of the groove will be low, and the opening pressure will be low.

[0150] As shown in Comparative Example 3 in Table 1, if d1 is too large, the thickness of the pressure-bearing surface will be only about 0.1 mm. The pressure-bearing surface is prone to cracking and failure under normal operating conditions, resulting in low safety.

[0151] Table 1

[0152]

[0153] In some embodiments, combined with Figure 4 As shown, the peripheral grooves 22 are continuously and non-closedly arranged on the outer periphery of the groove surface 23, and the groove surface 23 forms a compacted portion 26 in the area adjacent to the overlapping portion 21 where no peripheral grooves 22 are provided.

[0154] In some embodiments, the thickness d4 of the compacted portion 26 is D4-d1, where D4 is the thickness of the overlapping portion 21 and d1 is the height difference between the groove surface 23 and the overlapping portion 21 in a direction perpendicular to the overlapping portion 21.

[0155] Optionally, the thickness d4 of the compacted part 26 can be in the range of 0.25mm≤d4≤0.35mm.

[0156] Optionally, the overlap portion 21 of the explosion-proof valve 2 is constructed as a racetrack-shaped structure, wherein the racetrack-shaped structure includes straight segments arranged parallel to each other on both sides of the explosion-proof valve 2 along the width direction, and arc segments arranged at both ends of the straight segments along the length direction.

[0157] The groove surface 23 is continuously provided inside the overlapping part 21.

[0158] In this embodiment, the compaction part 26 corresponds to one of the straight segments of the runway-shaped structure, and the length of the compaction part 26 is Z, and Z satisfies: Z = W - (4mm ~ 6mm), where W is the distance between the centers of the two semicircles of the arc segments at both ends of the straight segment length direction.

[0159] By continuously and non-closedly setting the peripheral grooves 22 on the outer periphery of the groove surface 23, a compaction part 26 is formed in the area adjacent to the overlap portion 21 where no peripheral grooves 22 are provided. This allows the explosion-proof valve 2 to burst open along the path formed by the peripheral grooves 22 when it is under pressure. The bursting groove surface 23 is then connected to the overlap portion 21 through the compaction part 26. This ensures the opening area of ​​the explosion-proof valve 2 while preventing the bursting groove surface 23 from flying out. This prevents the bursting groove surface 23 from damaging other external structures when moving at high speed, and also prevents the flying groove surface 23 from blocking the explosion-proof valves 2 of other batteries, thus preventing accidental overlap from causing a short circuit.

[0160] Combination Figure 4 As shown, when the grooved surface 23 forms a compacted portion 26 in the area adjacent to the overlapping portion 21 and without peripheral notches 22, the explosion-proof valve 2 can burst open along the path of the peripheral notches 22, and the burst-opened grooved surface 23 remains connected to the overlapping portion 21 through the compacted portion 26. This ensures the opening area of ​​the explosion-proof valve 2 while preventing the burst-opened grooved surface 23 from flying out. Combined with... Figure 15 It can be seen that even though reinforcing ribs 25 are formed on the groove surface 23, because the remaining thickness d3 of the reinforcing ribs 25 is greater than the remaining thickness d2 of the peripheral grooves 22, in the event of thermal runaway, the explosion-proof valve 2 will preferentially burst open from the path defined by the peripheral grooves 22, rather than from the path defined by the reinforcing ribs 25. This ensures that the reinforcing ribs 25 only serve a structural reinforcement function, guaranteeing that the area after opening is large enough. The opening path formed by the original peripheral grooves 22 has fewer burrs and a smoother opening.

[0161] In some embodiments, combined with Figure 3As shown, on the plane perpendicular to the body 1, the projection of the peripheral groove 22 is located within the projection range of the exhaust hole 11; and on the plane parallel to the body 1, the minimum distance between the edge of the peripheral groove 22 and the exhaust hole 11 on the edge of the body 1 is c, and satisfies: 1mm≤c≤3mm.

[0162] Since the projection of the peripheral groove 22 is located within the projection range of the vent hole 11, when the explosion-proof valve 2 opens along the peripheral groove 22, it can avoid the vent hole 11 interfering with the opening area of ​​the groove surface 23.

[0163] Meanwhile, when the explosion-proof valve 2 bursts open, it does not spray parallel to the plane of the housing 3 or the battery cover. Instead, a point on the peripheral groove 22 tears first, causing the entire peripheral groove 22 to tear. At this time, the explosion-proof valve 2 will be in an inclined state, detaching from the plane of the housing 3 or the battery cover at a certain angle. If a redundancy of 1mm≤c≤3mm is not designed, the explosion-proof valve 2 will get stuck on the housing 3 or the battery cover and cannot burst open effectively, which will easily cause interference. By limiting the lower limit of the minimum distance c between the edge of the peripheral groove 22 and the edge of the vent hole 11 on the plane of the body 1, parallel to the plane of the body 1, interference of the vent hole 11 with the opening area of ​​the groove surface 23 can be avoided. By limiting the upper limit of the minimum distance c between the edge of the peripheral groove 22 and the edge of the vent hole 11 on the plane of the body 1, parallel to the plane of the body 1, the explosion-proof valve 2 can be guaranteed to have a sufficient opening area, avoiding the vent hole 11 from being too large.

[0164] As shown in Examples 1 and 2 of Table 2, the c value is within the normal range of 1mm ≤ c ≤ 3mm, the burst pressure is precisely controllable, the vent hole 11 does not affect the normal opening of the explosion-proof valve, and the burst stability is good. At the same time, it avoids interference between the vent hole 11 and the opening area of ​​the groove surface 23, ensuring the explosion-proof valve opens smoothly without jamming.

[0165] As shown in Comparative Example 1 in Table 2, c = -0.5mm. At this time, the value of c is too small. When the explosion-proof valve is opened, it is blocked by the aluminum plate, which makes it impossible to open the valve and affects the normal blasting.

[0166] As shown in Comparative Example 2 in Table 2, c = 0.5 mm. At this time, the c value is low, which does not meet the manufacturing process requirements, and there is an unstable valve opening situation.

[0167] As shown in Comparative Example 3 of Table 2 below, c = 4mm. At this time, the value of c is too large. Since the battery structure is relatively compact, the area of ​​the vent hole 11 cannot be increased indefinitely. When the area of ​​the vent hole 11 is constant, the value of c is too large, which will result in a small air-receiving area of ​​the explosion-proof valve 2, leading to an increase in opening pressure. If the opening pressure exceeds the upper limit, it will be unable to vent in time, which poses a significant safety hazard.

[0168] Table 2

[0169]

[0170] Referring to Table 3 below, the opening effect of the explosion-proof valve 2 provided in the embodiments of this application is verified through several sets of test examples.

[0171] Example 1: The explosion-proof valve 2 has a length of 31.7 mm and a width of 19.7 mm. The thickness D4 of the overlap 21 of the explosion-proof valve 2 is 0.5 mm, the thickness d4 of the compacted part 26 is 0.3 mm, the residual thickness d2 of the peripheral groove 22 is 0.12 mm, the residual thickness d3 of the reinforcing rib groove 25 is 0.20 mm, the distance between d3 and d2 is 0.08 mm, and the length Z of the compacted part 26 is 6 mm. A burst test was performed on the cover plate, and the burst pressure was measured to be 0.605 MPa (the design value of burst pressure is 0.6 ± 0.2 MPa). The explosion-proof valve 2 successfully burst open along the peripheral groove 22.

[0172] Example 2: The explosion-proof valve 2 has a length of 45mm and a width of 27mm. The thickness D4 of the overlap 21 of the explosion-proof valve 2 is 0.55mm, the thickness d4 of the compacted part 26 is 0.35mm, the residual thickness d2 of the peripheral groove 22 is 0.16mm, the residual thickness d3 of the reinforcing rib groove 25 is 0.25mm, the distance between d3 and d2 is 0.09mm, and the length Z of the compacted part 26 is 6mm. An explosion test was performed on the battery cover, and the explosion pressure was measured to be 0.895Mpa (the design value of explosion pressure is 0.6±0.2Mpa). The explosion-proof valve 2 successfully burst open along the peripheral groove 22.

[0173] Example 3: The explosion-proof valve 2 has a length of 31.7 mm and a width of 19.7 mm. The thickness D4 of the overlap 21 of the explosion-proof valve 2 is 0.5 mm, the thickness d4 of the compacted part 26 is 0.3 mm, the residual thickness d2 of the peripheral groove 22 is 0.12 mm, the residual thickness d3 of the reinforcing rib groove 25 is 0.20 mm, the d3-d2 is 0.08 mm, and the length Z of the compacted part 26 is 6 mm. A breathing test was conducted (internal and external pressure difference of 0.1 MPa, 50,000 tests). The internal and external pressure difference was set to 0.1 MPa, and the test was conducted 50,000 times. Subsequently, a burst test was conducted on the battery cover. The explosion-proof valve 2 successfully burst open along the peripheral groove 22, and the burst pressure was measured to be 0.590 MPa (the burst pressure design value is 0.6 ± 0.2 MPa). It can be seen that the burst pressure meets the design requirements.

[0174] Example 4: The explosion-proof valve 2 has a length of 31.7 mm and a width of 19.7 mm. The thickness D4 of the overlap 21 of the explosion-proof valve 2 is 0.5 mm, the thickness d4 of the compacted part 26 is 0.3 mm, the residual thickness d2 of the peripheral groove 22 is 0.15 mm, the residual thickness d3 of the reinforcing rib groove 25 is 0.20 mm, the distance between d3 and d2 is 0.05 mm, and the length Z of the compacted part 26 is 6 mm. An explosion test was performed on the battery cover, and the explosion pressure was measured to be 0.585 MPa (the design value of explosion pressure is 0.6 ± 0.2 MPa). The explosion-proof valve 2 successfully burst open along the peripheral groove 22.

[0175] Comparative Example 1: The explosion-proof valve 2 has a length of 31.7 mm and a width of 19.7 mm. The thickness D4 of the overlap 21 of the explosion-proof valve 2 is 0.5 mm, the thickness d4 of the compacted part 26 is 0.3 mm, the residual thickness d2 of the peripheral groove 22 is 0.12 mm, the residual thickness d3 of the reinforcing rib groove 25 is 0.13 mm, the distance between d3 and d2 is 0.01 mm, and the length Z of the compacted part 26 is 6 mm. In the battery cover explosion test, the explosion pressure was measured to be 0.635 MPa (the design value of explosion pressure is 0.6 ± 0.2 MPa). The explosion-proof valve 2 did not burst open along the peripheral groove 22, but rather along the reinforcing rib groove 25, resulting in a small venting area after opening.

[0176] Comparative Example 2: The explosion-proof valve 2 has a length of 31.7 mm and a width of 19.7 mm. The thickness D4 of the overlap 21 of the explosion-proof valve 2 is 0.5 mm, the thickness d4 of the compacted part 26 is 0.3 mm, the residual thickness d2 of the peripheral notch 22 is 0.12 mm, the residual thickness d3 of the reinforcing rib notch 25 is 0.14 mm, the difference between d3 and d2 is 0.02 mm, and the length Z of the compacted part 26 is 6 mm. In the battery cover burst test, the burst pressure was measured to be 0.645 MPa (the design burst pressure is 0.6 ± 0.2 MPa). The explosion-proof valve 2 did not burst open along the peripheral notch 22, but rather along the reinforcing rib notch 25, resulting in a smaller venting area after opening (e.g., ...). Figure 9 (as shown);

[0177] Comparative Example 3: The explosion-proof valve 2 has a length of 31.7 mm and a width of 19.7 mm. The thickness D4 of the overlap 21 of the explosion-proof valve 2 is 0.5 mm, the thickness d4 of the compacted part 26 is 0.3 mm, the residual thickness d2 of the peripheral notch 22 is 0.08 mm, the residual thickness d3 of the reinforcing rib notch 25 is 0.20 mm, the distance between d3 and d2 is 0.12 mm, and the length Z of the compacted part 26 is 6 mm. A breathing test was conducted (internal and external pressure difference of 0.1 MPa, 50,000 tests). After the internal and external pressure difference was set to 0.1 MPa and the test was conducted 50,000 times, the battery cover was then subjected to a burst test. The burst pressure was measured to be 0.349 MPa (the design value of burst pressure is 0.6 ± 0.2 MPa). It can be seen that the burst pressure does not meet the design requirements.

[0178] Table 3

[0179]

[0180]

[0181] By comparing the embodiments and comparative examples in Table 3 above, it can be clearly seen that the reinforcing ribs in the middle of the explosion-proof valve 2 can enhance the fatigue resistance of the explosion-proof valve 2.

[0182] Furthermore, when d3-d2 satisfies 30μm≤d3-d2≤100μm, the explosion-proof valve can successfully burst open along the peripheral grooves. However, when d3-d2 exceeds this range, the explosion-proof valve does not burst open along the peripheral grooves, but rather along the reinforcing rib grooves. This results in a small venting area after opening, making it impossible to promptly discharge overheated gas; or the burst pressure may be too low to meet design requirements, easily leading to accidental triggering and posing a significant safety hazard.

[0183] In some embodiments, the battery dimensions satisfy the following: battery length ranges from 100mm to 600mm, battery width ranges from 50mm to 250mm, and battery height ranges from 10mm to 100mm; or, the battery dimensions satisfy the following: battery length ranges from 600mm to 1500mm, battery width ranges from 50mm to 250mm, and battery height ranges from 10mm to 100mm; a sealed cavity is formed inside the body 1, and an electrode assembly is disposed within the sealed cavity.

[0184] The material systems for battery cells include various types, such as lithium iron phosphate (LFP), ternary lithium (NCM), lithium manganese iron phosphate, cobalt-free systems, and sodium batteries. Different cell systems correspond to different explosion-proof valve 2 burst pressures. For example, the explosion-proof valve 2 burst pressure range for LFP is 0.4 MPa to 0.8 MPa; for NCM, it is 0.7 MPa to 1.2 MPa; for cobalt-free systems, it is 0.8 MPa to 1.2 MPa; and for sodium batteries, it is 0.7 MPa to 1.1 MPa. Furthermore, the explosion-proof valve 2 burst pressure range for semi-solid-state / all-solid-state batteries is 0.7 MPa to 1.2 MPa. This application defines and protects parameters based on the size and shape of the explosion-proof valve 2, but is not limited to any particular system.

[0185] Referring to Table 4 below, the opening effect of the explosion-proof valve 2 provided in the embodiments of this application is verified through several sets of test examples.

[0186] Example 1: The explosion pressure of the battery cover explosion-proof valve 2 is 0.9±0.2Mpa, the welding edge distance f of the explosion-proof valve 2 is 4mm, and after the cover is welded, the finished battery is subjected to an explosion test, and the explosion pressure is 0.952Mpa.

[0187] Example 2: The explosion pressure of the battery cover explosion-proof valve 2 is 0.9±0.2Mpa, the welding edge distance f of the explosion-proof valve 2 is 6mm, and after the cover is welded, the finished battery is subjected to an explosion test, and the explosion pressure is 0.945Mpa.

[0188] Example 3: The burst pressure of the explosion-proof valve 2 on the battery cover is 0.9±0.2 MPa, and the welding edge distance f of the explosion-proof valve 2 is 6 mm. After welding the cover, the finished battery is subjected to a large-area extrusion vibration test and the leakage rate of the explosion-proof valve 2 is tested. The helium leak detection rate is 6.0×10-8 Pa·m3 / s; standard (1×10-7 Pa·m3 / s).

[0189] Comparative Example 1: The burst pressure of the explosion-proof valve 2 on the battery cover is 0.9±0.2Mpa, and the welding edge distance f of the explosion-proof valve 2 is 3mm. After the cover is welded, the finished battery is subjected to an explosion test, and the burst pressure is 0.686Mpa (unqualified).

[0190] Comparative Example 2: The burst pressure of the explosion-proof valve 2 on the battery cover is 0.9±0.2Mpa, and the welding edge distance f of the explosion-proof valve 2 is 2.5mm. After the cover is welded, the finished battery is subjected to an explosion test, and the burst pressure is 0.635Mpa (unqualified).

[0191] Comparative Example 3: The burst pressure of the explosion-proof valve 2 on the battery cover is 0.9±0.2Mpa, and the welding edge distance f of the explosion-proof valve 2 is 2.5mm. After the cover is welded, the finished battery is subjected to a large-area extrusion vibration test and the leakage rate of the explosion-proof valve 2 is tested. The helium leak detection rate is 7.0×10-7pa.m3 / s; standard (1×10-7pa.m3 / s).

[0192] Table 4

[0193]

[0194]

[0195] Further, see Figures 19 to 21 In this embodiment of the application, the body 1 includes a plurality of plates 12 and an electrode group. The plurality of plates 12 are interconnected to form a sealed cavity, and the electrode group is disposed in the sealed cavity.

[0196] At least one plate 12 has vent holes 11 and receiving grooves 13 arranged and communicating with each other along the second direction Y. It is understood that the multiple interconnected plates 12 can be integrally formed into the battery housing 3, or they can be separate housing 3 and battery cover; the vent holes 11 and receiving grooves 13 can be provided on the battery housing 3 or on the battery cover.

[0197] The battery also includes an explosion-proof valve 2, which is located in the receiving groove 13 and covers the vent hole 11. The explosion-proof valve 2 is connected to the plate 12.

[0198] See Figure 20 and Figure 21 In some embodiments, the receiving slot 13 is located on the side of the vent 11 near the battery.

[0199] See Figures 22 to 24 In other embodiments, the receiving slot 13 is located on the side of the vent 11 away from the battery.

[0200] See Figure 25 and Figure 27 Along the first direction X, the receiving groove 13 has a first dimension D1, and the explosion-proof valve 2 has a second dimension D2, satisfying: 0.02mm≤(D1-D2) / 2≤0.2mm. It can be understood that the value of (D1-D2) / 2 can be any value among 0.02mm, 0.05mm, 0.1mm, 0.15mm, and 0.2mm, or a range between any two values.

[0201] The plate 12 can be made of aluminum sheet and is connected to the explosion-proof valve 2 by welding to form a clearance fit. The explosion-proof valve 2 and the plate 12 fit tightly. If the gap is too small, assembly will be difficult, and if the gap is too large, it will lead to welding defects such as explosion points. When the relationship between the first dimension D1 of the receiving groove 13 and the second dimension D2 of the explosion-proof valve 2 meets the above-mentioned value range, the overall strength of the explosion-proof valve 2 and the plate 12 after welding can be ensured.

[0202] See Figure 25 and Figure 27 In some embodiments, the first dimension D1 satisfies: 5mm≤D1≤70mm; or the second dimension D2 satisfies: 5mm≤D2≤70mm. It can be understood that the value of D1 or D2 can be any value or a range between any two of 5mm, 10mm, 20mm, 30mm, 40mm, 50mm, 60mm, and 70mm. When the first dimension D1 or the second dimension D2 satisfies the above value range, it can meet the opening area requirements of battery explosion-proof valves 2 of many specifications.

[0203] See Figure 25 and Figure 26 In some embodiments, the plate 12 has two first surfaces 121 disposed opposite to each other along a first direction X, the two first surfaces 121 being used to enclose and form a receiving groove 13;

[0204] The plate 12 also includes two side surfaces 122 that are opposite to each other along the first direction X, and two first surfaces 121 are located between the two side surfaces 122;

[0205] Among them, along the first direction X, there is a minimum dimension L1 between the side surface 122 and the first surface 121, which satisfies: 2mm≤L1≤25mm.

[0206] It is understandable that the value of L1 can be any value or a range between any two of 2mm, 5mm, 10mm, 15mm, 20mm, and 25mm. When the minimum dimension L1 between the side 122 and the first side 121 meets the above value range, it can ensure the overall strength of the plate 12 and avoid the local high temperature generated during the welding of the battery casing 3 and the battery from having a thermal effect on the explosion-proof valve 2, which may cause deformation or even cracking failure.

[0207] See Figure 27 and Figure 28 In some embodiments, the explosion-proof valve 2 includes a grooved surface 23 and an overlap portion 21 connected to the outer periphery of the grooved surface 23. The overlap portion 21 extends away from the second direction Y and is connected to the plate 12.

[0208] Along the second direction Y, the receiving groove 13 has a third dimension D3, and the overlapping part 21 has a fourth dimension D4, satisfying: 0.02mm≤D3-D4≤0.2mm.

[0209] It is understandable that the values ​​of D3-D4 can be any value or any range between two of 0.02mm, 0.05mm, 0.15mm, and 0.2mm. When the values ​​of D3-D4 meet the above range, it can avoid the problem of excessive height difference when the explosion-proof valve 2 is assembled into the receiving groove 13, and at the same time avoid problems such as pores or uneven welds when the explosion-proof valve 2 and the plate 12 are welded.

[0210] See Figure 26 and Figure 28 In some embodiments, the third dimension D3 satisfies: 0.3mm≤D3≤2mm. It can be understood that the value of D3 can be any value among 0.3mm, 0.5mm, 1mm, 1.5mm, and 2mm, or any range between any two values. When the value of D3 satisfies the above range, the welding strength of the explosion-proof valve 2 and the plate 12 can be guaranteed, and sufficient height can be used to accommodate the welding penetration depth, so as to ensure the stable connection between the formed explosion-proof valve 2 and the plate 12.

[0211] See Figure 28 In some embodiments, the fourth dimension D4 satisfies: 0.3mm≤D4≤2mm. It can be understood that the value of D4 can be any value among 0.3mm, 0.5mm, 1mm, 1.5mm, and 2mm, or any range between any two values. When the value of D4 satisfies the above range, the welding strength of the explosion-proof valve 2 and the plate 12 can be further guaranteed.

[0212] See Figure 27 and Figure 28 In some embodiments, the explosion-proof valve 2 has a peripheral groove 22 on the side near the vent 11. Along the first direction X, there is a first distance L2 between the peripheral groove 22 and the overlapping portion 21, satisfying: 0.3mm ≤ L2 ≤ 3mm. It can be understood that the value of L2 can be any value among 0.3mm, 1mm, 1.5mm, 2mm, 2.5mm, and 3mm, or any range between any two values. When the first distance L2 satisfies the above value range, the peripheral groove 22 of the explosion-proof valve 2 is less likely to be deformed and fail due to the heat effect of welding, and it is also not too large, which would reduce the effective usable area of ​​the explosion-proof valve 2.

[0213] See Figure 25 In some embodiments, along the first direction X, the exhaust port 11 has a fifth dimension D5, which satisfies: 0.25mm≤(D1-D5) / 2≤5mm. It can be understood that the value of D1-D5 can be any value or a range between any two of 0.5mm, 1mm, 2mm, 3mm, 4mm, and 5mm. When the value of D1-D5 satisfies the above value range, the stability of the connection between the explosion-proof valve 2 and the plate 12 can be guaranteed.

[0214] See Figure 28 In some embodiments, along the first direction X, the overlapping portion 21 has a sixth dimension D6, satisfying: 0.5mm≤D6≤3mm. It can be understood that the value of D6 can be any value among 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, and 3mm, or a range between any two values.

[0215] Based on the above embodiments, a second spacing L3 is further provided, L3 = D5 - [D2 - (D6 + L2) × 2], and the second spacing L3 satisfies: 0.5mm ≤ L3 ≤ 5mm. It can be understood that the value of L3 can be any value or any range between two of 0.5mm, 1mm, 2mm, 3mm, 4mm, and 5mm. When the value of L3 satisfies the above value range, it can ensure that the peripheral groove 22 on the explosion-proof valve 2 is located inside the exhaust port 11, so as to meet the requirement that the explosion-proof valve 2 can open normally and complete the pressure relief when thermal runaway occurs.

[0216] According to an embodiment of this application, another aspect provides a battery pack including the battery provided in any of the above embodiments.

[0217] According to an embodiment of this application, another aspect provides an electrical device including the battery pack provided in the above embodiments.

[0218] The battery provided in this application will be described below with reference to specific embodiments:

[0219] Example 1: This example provides a battery, such as... Figures 19 to 21 and Figures 25 to 28 As shown, it includes:

[0220] Plate 12, plate 12 has vent holes 11 and receiving grooves 13 arranged and communicating with each other along the second direction Y;

[0221] Explosion-proof valve 2 is located in the receiving groove 13 and the vent hole 11 is covered. Explosion-proof valve 2 is connected to plate 12.

[0222] Along the first direction X, the receiving groove 13 has a first dimension of 8.5 mm, and the explosion-proof valve 2 has a second dimension of 8.46 mm.

[0223] Plate 12 has two first surfaces 121 arranged opposite to each other along the first direction X, and the two first surfaces 121 are used to enclose and form a receiving groove 13;

[0224] The plate 12 also includes two side surfaces 122 that are opposite to each other along the first direction X, and two first surfaces 121 are located between the two side surfaces 122;

[0225] Among them, along the first direction X, the side surface 122 and the first surface 121 have a minimum dimension of 3.4mm.

[0226] The explosion-proof valve 2 includes a grooved surface 23 and an overlapping portion 21 connected to the outer periphery of the grooved surface 23. The overlapping portion 21 extends away from the second direction Y and is connected to the plate 12.

[0227] Along the second direction Y, the receiving groove 13 has a third dimension of 0.52 mm, and the overlapping portion 21 has a fourth dimension of 0.5 mm.

[0228] The explosion-proof valve 2 has a peripheral groove 22 on the side near the vent 11. Along the first direction X, there is a first gap of 0.3mm between the peripheral groove 22 and the overlap portion 21. The vent 11 has a fifth dimension of 8mm, and the overlap portion 21 has a sixth dimension of 0.18mm.

[0229] Examples 2 to 8: The battery structures provided in Examples 2 to 8 are the same as those in Example 1, with adjustments only made to the structural parameters.

[0230] Comparative Examples 1 to 8: The batteries provided in Comparative Examples 1 to 8 have the same structure as those in Example 1, with only the structural parameters being adjusted.

[0231] The structural parameters of Examples 1 to 8 and Comparative Examples 1 to 8 are shown in Table 5.

[0232] Table 5

[0233]

[0234]

[0235] Helium detection and safety tests were performed on the batteries formed from the batteries provided in Examples 1 to 8 and Comparative Examples 1 to 8. The test results are shown in Table 6.

[0236] The helium breath test method is as follows: The helium breath test refers to the method of testing the airtightness of the battery's explosion-proof valve 2 using a helium mass spectrometer. The test requirements are: at the battery's explosion-proof valve 2, 0.15 MPa for 30 seconds at each state, from the inside out and from the outside in; after 10 cycles of the breath test, the leakage rate is <10^-7 Pa. 3 If the burst pressure is within tolerance range and the pressure is within the specified range, then the explosion-proof valve 2 meets the sealing requirements.

[0237] Table 6

[0238]

[0239]

[0240] See Figure 29 When the battery casing 3 is impacted, the surface will show signs such as Figure 29 The cracks or damages shown caused the housing 3 of the batteries provided in Comparative Example 1, Comparative Example 2, Comparative Example 4, Comparative Example 7, and Comparative Example 8 to rupture during the safety test, rendering the batteries unusable.

[0241] As can be seen from the test results in Table 6:

[0242] Comparing Example 1 and Comparative Example 1, the two battery covers only differ in the value of (D1 - D2) / 2. In Comparative Example 1, this value is too small, and the other values are the same. In Example 1, the explosion-proof valve 2 is welded normally, the helium leak detection rate of the battery cover is qualified, and the explosion-proof valve 2 opens normally during the test. The housing 3 does not show any rupture or failure, and the thermal runaway test is passed. In Comparative Example 1, due to the too small gap between the explosion-proof valve 2 and the battery cover, the assembly is difficult, resulting in deformation of the explosion-proof valve 2. The helium leak detection rate is unqualified. The opening time of the explosion-proof valve 2 is delayed during the test. The housing 3 has already ruptured and failed, but the explosion-proof valve 2 still has not opened, failing to provide safety protection during the use of the battery.

[0243] Comparing Example 2 and Comparative Example 2, the two battery covers only differ in the value of D3 - D4. In Comparative Example 2, this value is too small, and the other values are the same. In Example 2, the explosion-proof valve 2 is welded normally, the helium leak detection rate of the battery cover is qualified, and the explosion-proof valve 2 opens normally during the test. The housing 3 does not show any rupture or failure, and the thermal runaway test is passed. In Comparative Example 2, there are blast holes in the welding of the explosion-proof valve 2 and the weld seam is uneven. The helium leak detection rate is unqualified. The opening time of the explosion-proof valve 2 is delayed during the test. The housing 3 has already ruptured and failed, but the explosion-proof valve 2 still has not opened, failing to provide safety protection during the use of the battery.

[0244] Comparing Example 3 and Comparative Example 3, the two battery covers only differ in the value of (D1 - D5) / 2. In Comparative Example 3, this value is too small, and the other values are the same. In Example 3, the explosion-proof valve 2 is welded normally, the helium leak detection rate of the battery cover is qualified, and the explosion-proof valve 2 opens normally during the test. The housing 3 does not show any rupture or failure, and the thermal runaway test is passed. In Comparative Example 3, although there is no obvious abnormality in the welding of the battery cover and the helium leak detection rate is qualified, but when the explosion-proof valve 2 arrives, the explosion-proof valve 2 does not open, posing a safety hazard during the use of the battery.

[0245] Comparing Comparative Example 4 with Proportion Example 4, the cover plates of the two only differ in L3, and the other dimensions are the same. Among them, L3 in Proportion Example 4 exceeds the lower limit of 0.5 to 3. The explosion-proof valve 2 in Example 4 is welded normally, the helium leak detection rate of the battery cover plate is qualified, and the explosion-proof valve 2 opens normally during the test, and the housing 3 does not show any rupture failure, and the thermal runaway test passes. In Proportion Example 4, although there is no obvious abnormality in the welding of the battery cover plate and the helium leak detection rate is qualified, the distance from the peripheral notch 22 of the explosion-proof valve 2 to the hole of the explosion-proof valve 2 is too small, and even the peripheral notch 22 is inside the hole of the explosion-proof valve 2, blocking the explosion-proof valve 2 from opening normally, resulting in the failure of the explosion-proof valve 2 during the test, the housing 3 has ruptured and failed, and the explosion-proof valve 2 still has not opened, unable to play a safety protection role during the use of the battery.

[0246] Comparing Example 5 with Proportion Example 5, the two battery cover plates only differ in L3, and the other dimensions are the same. Among them, L3 in Proportion Example 5 exceeds the lower limit of 0.5 to 3. The explosion-proof valve 2 in Example 5 is welded normally, the helium leak detection rate of the battery cover plate is qualified, and the explosion-proof valve 2 opens normally during the test, and the housing 3 does not show any rupture failure, and the thermal runaway test passes. In Proportion Example 5, although there is no obvious abnormality in the welding of the battery cover plate and the helium leak detection is qualified, the distance from the peripheral notch 22 of the explosion-proof valve 2 to the welding position is too large, resulting in a reduction in the blasting area of the peripheral notch 22 of the explosion-proof valve 2, reducing the blasting pressure of the explosion-proof valve 2, causing the explosion-proof valve 2 to open prematurely, and there are safety hazards during the use of the battery.

[0247] Comparing Example 6 with Proportion Example 6, the two battery cover plates only differ in the value of (D1 - D5) / 2. Among them, this value in Proportion Example 6 is too large, and the other values are the same. The explosion-proof valve 2 in Example 6 is welded normally, the helium leak detection rate of the battery cover plate is qualified, and the explosion-proof valve 2 opens normally during the test, and the housing 3 does not show any rupture failure, and the thermal runaway test passes. In Proportion Example 6, although there is no obvious abnormality in the welding of the battery cover plate and the helium leak detection is qualified, the distance from the peripheral notch 22 of the explosion-proof valve 2 to the welding position is too large, resulting in a reduction in the blasting area of the peripheral notch 22 of the explosion-proof valve 2, reducing the blasting pressure of the explosion-proof valve 2, causing the explosion-proof valve 2 to open prematurely, and there are safety hazards during the use of the battery.

[0248] Comparing Example 7 with Proportion Example 7, the two battery cover plates only differ in the value of D3 - D4. Among them, this value in Proportion Example 7 is too large, and the other values are the same. The explosion-proof valve 2 in Example 7 is welded normally, the helium leak detection rate of the battery cover plate is qualified, and the explosion-proof valve 2 opens normally during the test, and the housing 3 does not show any rupture failure, and the thermal runaway test passes. In Proportion Example 7, there are explosion holes in the welding of the explosion-proof valve 2 and the penetration depth is too small, the helium leak detection rate is unqualified, the opening time of the explosion-proof valve 2 is delayed during the test, the housing 3 has ruptured and failed, and the explosion-proof valve 2 still has not opened, unable to play a safety protection role during the use of the battery.

[0249] Comparing Example 8 and Comparative Example 8, the only difference between the two battery covers is the (D1-D2) / 2 value, where this value is too large in Comparative Example 8, while all other values ​​are the same. In Example 8, the explosion-proof valve 2 is welded normally, the helium leak detection rate of the battery cover is qualified, and the explosion-proof valve 2 opens normally during the test, and the shell 3 does not experience any cracking or failure, thus passing the thermal runaway test. However, in Comparative Example 8, due to the excessive gap between the battery cover and the explosion-proof valve 2, there were incomplete welds and pores during welding, resulting in a failed helium leak detection rate. The explosion-proof valve 2 opened late during the test, and even after the shell 3 had cracked and failed, the explosion-proof valve 2 still did not open, failing to provide safety protection for the battery during use.

[0250] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and all such modifications and variations fall within the scope defined by the appended claims.

Claims

1. A battery, characterized in that, include: The body has an exhaust hole, and a receiving groove is formed in the area of ​​the body corresponding to the exhaust hole. An explosion-proof valve is installed inside the receiving groove; On a plane parallel to the body, the minimum distance between the weld mark formed by welding the explosion-proof valve and the receiving groove and the edge of the body is f, and f≥4mm. The explosion-proof valve includes: a grooved surface and an overlapping portion surrounding the circumferential edge of the grooved surface; at least a portion of the grooved surface near the overlapping portion is recessed to form peripheral grooves; In a plane perpendicular to the body, the projection of the peripheral groove is located within the projection range of the vent hole; and in a plane parallel to the body, the minimum distance between the edge of the peripheral groove and the vent hole on the edge of the body is c, and satisfies: 1mm≤c≤3mm; In the direction perpendicular to the overlapping portion, the height difference between the groove surface and the overlapping portion is d1, and satisfies 0.15mm≤d1≤0.2mm; The groove surface is also formed with reinforcing rib markings, which are located on the side of the peripheral markings away from the overlapping portion. In the direction perpendicular to the groove surface, the projections of the reinforcing rib markings and the peripheral markings do not overlap. In the direction perpendicular to the groove surface, the residual thickness of the peripheral markings is d2, and the residual thickness of the reinforcing rib markings is d3, satisfying: 120μm≤d3≤180μm; 30μm≤d3-d2≤100μm. The dimensions of the battery satisfy the following conditions: the battery length ranges from 100mm to 600mm, the battery width ranges from 50mm to 250mm, and the battery height ranges from 10mm to 100mm; or, the dimensions of the battery satisfy the following conditions: the battery length ranges from 600mm to 1500mm, the battery width ranges from 50mm to 250mm, and the battery height ranges from 10mm to 100mm. When the battery cell material is lithium iron phosphate, the burst pressure range of the explosion-proof valve is 0.4 MPa-0.8 MPa. When the battery cell material is ternary lithium, the burst pressure range of the explosion-proof valve is 0.7 MPa-1.2 MPa. When the battery cell material is a cobalt-free system, the burst pressure range of the explosion-proof valve is 0.8 MPa-1.2 MPa; When the battery cell material is sodium, the burst pressure range of the explosion-proof valve is 0.7 MPa to 1.1 MPa. When the battery cell is a semi-solid-state battery or an all-solid-state battery, the burst pressure range of the explosion-proof valve is 0.7 MPa to 1.2 MPa.

2. The battery according to claim 1, characterized in that, In a plane perpendicular to the body, the depth of the receiving groove is D3, and the thickness of the overlap of the explosion-proof valve is D4; the explosion-proof valve is received in the receiving groove and satisfies: 0mm≤D3-D4≤0.2mm; The value range of D4 is 0.4mm≤D4≤0.6mm; the value range of D3 is 0.5mm≤D3≤0.6mm.

3. The battery according to claim 1, characterized in that, The residual thickness d2 of the peripheral groove is in the range of 60μm≤d2≤180μm; the peripheral groove is continuously provided on the outer periphery of the groove surface.

4. The battery according to any one of claims 1 to 3, characterized in that, The body is enclosed to form a sealed cavity, and an electrode assembly is provided inside the sealed cavity; The peripheral groove formed by the recessed groove surface is formed by the side of the groove surface away from the electrode group and recessed towards the electrode group; Alternatively, the peripheral grooves formed by the recessed groove surface are formed by the recessed side of the groove surface near the electrode group in a direction away from the electrode group.

5. The battery according to claim 1, characterized in that, The reinforcing rib grooves are formed by the recesses in the grooved surface.

6. The battery according to claim 1, characterized in that, The reinforcing rib grooves include at least two arc-shaped grooves, the two ends of which intersect with the surrounding grooves, and at least two arc-shaped grooves partially overlap to form a groove overlap area; Alternatively, the reinforcing rib grooves include at least two arc-shaped grooves, the two ends of which intersect with the peripheral grooves, and the at least two arc-shaped grooves do not overlap with each other; Alternatively, the reinforcing rib groove is constructed as a Y-shaped groove, with at least one end of the Y-shaped groove intersecting the peripheral groove; Alternatively, the reinforcing rib groove is constructed as a zigzag groove, with at least one end of the zigzag groove intersecting with the peripheral groove; Alternatively, the reinforcing rib grooves may be constructed as multiple straight grooves, and these multiple straight grooves may not be connected to the surrounding grooves, and the multiple straight grooves may not intersect each other; The reinforcing rib groove is located in the central area of ​​the groove surface; The reinforcing rib grooves are symmetrically arranged along the central axis of the explosion-proof valve along its length, and / or the reinforcing rib grooves are symmetrically arranged along the central axis of the explosion-proof valve along its width.

7. The battery according to claim 1, characterized in that, The body includes multiple plates and an electrode assembly. The multiple plates are connected to each other to form a sealed cavity, and the electrode assembly is disposed within the sealed cavity. At least one of the plates has the vent holes and the receiving grooves arranged and communicating with each other along a second direction; the explosion-proof valve is connected to the plate and covers the vent holes; Wherein, along the first direction, the receiving groove has a first dimension D1, and the explosion-proof valve has a second dimension D2, satisfying: 0.02mm≤(D1-D2) / 2≤0.2mm; The overlapping portion is connected to the plate; Along the first direction, the peripheral groove has a certain width, and there is a first distance L2 between the edge of the peripheral groove near the overlapping part and the edge of the overlapping part near the peripheral groove, satisfying: 0.3mm≤L2≤3mm; Along the first direction, the vent has a fifth dimension D5, satisfying: 0.25mm≤(D1-D5) / 2≤2.5mm; Along the first direction, the overlapping portion has a sixth dimension D6, and the second dimension D2, the fifth dimension D5, the sixth dimension D6 and the first spacing L2 satisfy: 0.5mm≤D5-[D2-(D6+L2)×2]≤5mm; The first dimension D1 satisfies: 5mm≤D1≤70mm; or, the second dimension D2 satisfies: 5mm≤D2≤70mm; The plate has two first surfaces arranged opposite each other along the first direction, and the two first surfaces are used to enclose and form the receiving groove; the plate also includes two side surfaces that are opposite each other along the first direction, and the two first surfaces are located between the two side surfaces; wherein, along the first direction, the side surfaces and the first surfaces have a minimum dimension L1, which satisfies: 2mm≤L1≤25mm.

8. The battery according to claim 7, characterized in that, Along the second direction, the receiving groove has a third dimension D3, and the overlapping portion has a fourth dimension D4, satisfying: 0.02mm≤D3-D4≤0.2mm; The third dimension D3 satisfies: 0.3mm≤D3≤2mm; or the fourth dimension D4 satisfies: 0.3mm≤D4≤2mm.

9. A battery pack, characterized in that, Includes the battery as described in any one of claims 1 to 8.

10. An electrical appliance, characterized in that, Includes the battery pack as described in claim 9.

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