Battery case and battery

Abstract

The present application relates to the technical field of batteries. Disclosed are a battery case and a battery. The battery case comprises: a case body having an opening; and a cover plate that seals the opening to form an accommodating cavity, wherein the cover plate comprises a cover plate body and a folded edge arranged at an edge of the cover plate body; the folded edge extends in a direction facing away from the accommodating cavity; the folded edge is welded to the case body; a welding area is formed at the position where the folded edge and the case body are welded; in the extension direction of the folded edge, the cover plate body is located on the side of the welding area close to the accommodating cavity; and in a direction perpendicular to the upper surface of the cover plate body, the distance from the side of the welding area close to the accommodating cavity to the upper surface of the cover plate body is h, and the distance from the side of the folded edge away from the accommodating cavity to the side of the cover plate body close to the accommodating cavity is H, where 0.17≤h / H≤0.5. The present application can ensure that the cover plate can provide a buffering effect, thereby preventing the cover plate from detaching from the case body during thermal runaway, and the present application can also control the overall height of the cover plate to ensure the internal space of the case body, thereby ensuring the energy density of a battery cell.

Description

Battery casing and battery

[0001] Cross-references to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411506503.6, filed on October 28, 2024, entitled “Battery Casing 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 battery casings and batteries. Background Technology

[0004] As lithium-ion battery technology matures, lithium-ion batteries are increasingly widely used as power batteries in electric vehicles and energy storage. Lithium-ion battery packs typically consist of multiple cells, and existing batteries are generally categorized as cylindrical, pouch, and prismatic.

[0005] Existing prismatic batteries include a battery casing and cells housed within the casing. The battery casing includes a housing and a cover plate, which are fixed together by welding. The welded joints between the housing and the cover plate are easily damaged during battery thermal runaway, causing the entire cover plate to detach from the housing. This can further trigger thermal runaway in other batteries, potentially leading to battery pack fire and explosion, posing a significant safety hazard. Summary of the Invention

[0006] In view of this, this application provides a battery casing and a battery to solve the problem that the welding position of the casing and the cover plate is easily damaged during battery thermal runaway, causing the cover plate to detach from the casing.

[0007] In a first aspect, this application provides a battery casing, comprising: a casing having an opening; a cover plate sealing the opening to form a receiving cavity, the cover plate including a cover plate body and a flange disposed on the edge of the cover plate body, the flange extending in a direction away from the receiving cavity, the flange being welded to the casing, the welded portion of the flange and the casing forming a welding area, in the extension direction of the flange, the cover plate body being located on the side of the welding area near the receiving cavity, in a direction perpendicular to the upper surface of the cover plate body, the distance from the side of the welding area near the receiving cavity to the upper surface of the cover plate body is h, and the distance from the side of the flange away from the receiving cavity to the side of the cover plate body near the receiving cavity is H, wherein 0.17≤h / H≤0.5.

[0008] Secondly, this application also provides a battery, including: the aforementioned battery casing, and a battery cell, wherein the battery cell is disposed within a receiving cavity of the battery casing.

[0009] Beneficial effects: The shell and cover plate are fixed together by welding. If the ratio of h to H is too small, when the cover plate body is subjected to force, the force will be quickly transmitted to the weld, causing the weld to crack and failing to play a buffering role. The weakened buffering role makes the cover plate easy to detach from the shell during thermal runaway, posing a significant safety hazard. If the ratio of h to H is too large, the space inside the shell where the cover plate is located is large, which affects the energy density of the single cell and thus the capacity of the battery.

[0010] The ratio of h to H is in the range of 0.17 to 0.5. This ensures that the cover plate can play a buffering role and prevent the cover plate from detaching from the shell during thermal runaway. It can also solve the problem that the welding position between the shell and the cover plate is easily damaged during battery thermal runaway, causing the cover plate to detach from the shell. At the same time, it can control the overall height of the cover plate, ensure the internal space of the shell, and thus ensure the energy density of the individual battery. Attached Figure Description

[0011] 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.

[0012] Figure 1 is a perspective view of a battery casing according to an embodiment of this application;

[0013] Figure 2 is a top view of the battery casing shown in Figure 1;

[0014] Figure 3 is a cross-sectional view of the battery casing shown in Figure 2 along the AA direction;

[0015] Figure 4 is a magnified view of part B in Figure 3.

[0016] Explanation of reference numerals in the attached drawings: 1. Shell; 2. Cover plate; 201. Cover plate body; 202. Folded edge; 203. Transition section; 204. Welding area. Detailed Implementation

[0017] 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.

[0018] The embodiments of this application are described below with reference to Figures 1 to 4.

[0019] According to an embodiment of this application, in one aspect, a battery casing is provided, including: a housing 1 and a cover plate 2, the housing 1 having an opening; the cover plate 2 sealing the opening to form a receiving cavity, the cover plate 2 including a cover plate body 201 and a flange 202 disposed on the edge of the cover plate body 201, the flange 202 extending in a direction away from the receiving cavity, the flange 202 being welded to the housing 1, the welded portion of the flange 202 and the housing 1 forming a welding area 204, in the extending direction of the flange 202, the cover plate body 201 is located on the side of the welding area 204 near the receiving cavity, in a direction perpendicular to the upper surface of the cover plate body 201, the distance from the side of the welding area 204 near the receiving cavity to the upper surface of the cover plate body 201 is h, and the distance from the side of the flange 202 away from the receiving cavity to the side of the cover plate body 201 near the receiving cavity is H, wherein 0.17≤h / H≤0.5.

[0020] In the battery casing of this embodiment, the folded edges 202 of the casing 1 and the cover plate 2 are fixed together by welding. If the ratio of h to H is too small, when the cover plate body 201 is subjected to force, the force will be quickly transmitted to the weld, causing the weld to crack and failing to play a buffering role. The buffering role is weakened, which makes the cover plate easy to detach from the casing in the event of thermal runaway, posing a significant safety hazard. If the ratio of h to H is too large, the space inside the casing of the cover plate is large, which affects the energy density of the individual cells and thus the capacity of the battery.

[0021] Therefore, a ratio of h to H within the range of 0.17 to 0.5 can ensure that the cover plate 2 can play a buffering role and prevent the cover plate 2 from detaching from the shell 1 during thermal runaway. This can solve the problem to some extent that the welding position between the shell 1 and the cover plate 2 is easily damaged during battery thermal runaway, causing the cover plate 2 to detach from the shell 1. At the same time, it can control the overall height of the cover plate 2, ensure the internal space of the shell 1, and thus ensure the energy density of the single cell.

[0022] Specifically, the h / H ratio can preferably be 0.2, 0.25, 0.3, 0.35, 0.4 or 0.45.

[0023] Furthermore, the range of H is 0.5mm to 4mm. If H is large, it indicates that the overall height of the cover plate 2 is relatively high, and the cover plate 2 occupies a large space inside the housing 1, which in turn affects the energy density of the individual cells and thus the capacity of the battery. If H is small, it indicates that the overall height of the cover plate 2 is relatively low, making the welding area 204 smaller, and the welding between the folded edge 202 and the housing 1 is not firm. This makes it easy for the cover plate 2 to detach from the housing 1 when under stress, posing a significant safety hazard.

[0024] Therefore, H is within the range of 0.5mm to 4mm, which not only ensures that the weld between the folded edge 202 and the shell 1 is firm, but also controls the space occupied by the cover plate 2, thus ensuring the energy density of the battery.

[0025] Specifically, H can preferably be 1mm, 1.5mm, 1.6mm, 1.8mm, 2mm, 2.2mm, 2.5mm, 3mm, 3.2mm, 3.5mm or 3.8mm.

[0026] In one embodiment, h ranges from 0.1 mm to 1 mm. If h is too large, the cover plate 2 will be too high and occupy a large space inside the housing 1, which will greatly affect the height of the battery cells inside the housing 1 and thus affect the battery capacity. If h is too small, when the cover plate body 201 is subjected to force, the force will be quickly transmitted to the weld, causing the weld to crack and failing to play a buffering role. The cover plate 2 is also prone to separating from the housing 1 during thermal runaway.

[0027] Therefore, h is set in the range of 0.1mm to 1mm, that is, h is in a suitable range, and the height of cover plate 2 is in a suitable range. This reduces the impact on the capacity of the battery cell and plays a buffering role. Cover plate 2 is not easy to separate from the shell 1 during thermal runaway. This can solve the problem to a certain extent that the welding position of shell 1 and cover plate 2 is easily damaged during battery thermal runaway, causing cover plate 2 to detach from shell 1.

[0028] Specifically, h can preferably be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.8mm or 0.9mm.

[0029] In one embodiment, as shown in Figure 4, the ratio of the thickness T1 of the folded edge 202 to the thickness T2 of the shell 1 is 1.2:1 to 3:1. The thickness of the folded edge 202 refers to the distance between the inner and outer surfaces of the folded edge 202, which is the lateral dimension of the folded edge 202 in Figure 4. The thickness of the shell 1 refers to the distance between the inner and outer surfaces of the shell 1, which is the lateral dimension of the shell 1 in Figure 4.

[0030] Furthermore, if the ratio of the thickness T1 of the folded edge 202 to the thickness T2 of the shell 1 is too small, the risk of the folded edge 202 being welded through during the welding process is relatively high, affecting the seal and reducing the mechanical strength of the welded part, which can easily lead to damage to the battery when subjected to external force during use. If the ratio of the thickness T1 of the folded edge 202 to the thickness T2 of the shell 1 is too large, the welding power will increase, which will make it difficult to control the welding area 204 and affect the buffering performance.

[0031] Therefore, when the ratio of the thickness T1 of the folded edge 202 to the thickness T2 of the shell 1 is in the range of 1.2:1 to 3:1, the weld strength of the shell 1 and the cover plate 2 is better, ensuring the sealing performance. It also makes it easier to control the welding area 204 and ensure the buffering performance.

[0032] Specifically, the ratio of the thickness T1 of the folded edge 202 to the thickness T2 of the shell 1 can preferably be 1.5:1, 1.8:1, 2:1, 2.2:1 or 2.5:1.

[0033] Furthermore, the thickness of the casing 1 at the opening ranges from 0.1mm to 0.5mm. If the casing 1 is thicker, it increases the overall weight of the battery, thus affecting the weight of the electric vehicle. A thicker casing 1 requires more material, which increases manufacturing costs and occupies more space, potentially making it unsuitable for space-constrained applications. If the casing 1 is thinner, it is less mechanically strong and more susceptible to deformation or damage from external forces. A thinner casing 1 is also less effective at protecting the battery cells and may not be able to effectively prevent damage to the cells caused by external impacts or compression.

[0034] Therefore, the thickness of the shell 1 at the opening is in the range of 0.1mm to 0.5mm, which can ensure the strength of the shell 1 while controlling material costs, manufacturing costs and space occupation.

[0035] Specifically, the thickness of the shell 1 at the opening can preferably be 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm or 0.48mm.

[0036] Furthermore, the thickness of the folded edge 202 ranges from 0.2mm to 0.9mm. If the thickness of the folded edge 202 is too small, it is easy for the folded edge 202 to be welded through during the welding process between the shell 1 and the folded edge 202, forming weld slag and affecting the safety of the battery. If the thickness of the folded edge 202 is too large, the thicker folded edge 202 will increase the amount of material used, resulting in an increase in the overall weight of the cover plate 2. The thicker folded edge 202 requires more material, which will increase the manufacturing cost.

[0037] Therefore, the thickness of the folded edge 202 is in the range of 0.2mm to 0.9mm, which ensures the welding strength of the shell 1 and the cover plate 2 after welding, good sealing performance, and also makes it easy to control the amount of material used and the cost.

[0038] Specifically, the thickness of the folded edge 202 can preferably be 0.3mm, 0.4mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm or 0.8mm.

[0039] In one embodiment, as shown in FIG4, the top of the opening of the housing 1 is not higher than the top of the folded edge 202, that is, the top of the opening of the housing 1 is lower than the top of the folded edge 202, or the top of the opening of the housing 1 is flush with the top of the folded edge 202. This design facilitates the positioning of the cover plate 2 during installation and improves assembly efficiency.

[0040] Optionally, the top of the opening of the housing 1 is lower than the top of the folded edge 202, which improves the positioning effect of the cover plate 2 during the assembly process and reduces the assembly difficulty.

[0041] In one embodiment, 0.17 ≤ h / H ≤ 0.35. When the top of the opening of the housing 1 is lower than the top of the folded edge 202, a welding area 204 needs to be left. Therefore, the value of h needs to be reduced to meet the welding strength requirements, thereby improving the reliability of the battery and ensuring better sealing of the welded part to prevent liquid or gas leakage.

[0042] In one embodiment, as shown in FIG4, the cover plate body 201 and the folded edge 202 are connected by an arc-shaped transition portion 203. The arc radius R and h of the arc-shaped transition portion 203 satisfy the relationship: 0.5mm≤R+h≤1mm. The arc radius R of the arc-shaped transition portion 203 refers to the arc radius of the arc-shaped transition portion 203 connecting the cover plate body 201 and the folded edge 202 on the side of the cover plate 2 away from the receiving cavity.

[0043] Furthermore, when R+h is too small, the buffering performance is poor, and the cover plate 2 is prone to separating from the casing 1 during thermal runaway; when R+h is too large, the distance of the cover plate 2 into the interior of the casing 1 is too large, resulting in a smaller cavity space inside the casing 1 for accommodating the battery cells, thereby reducing the energy density of the individual battery cells.

[0044] Therefore, the arc-shaped transition section 203 can improve the buffering performance. When the relationship is satisfied, it can not only ensure the welding strength between the shell 1 and the folded edge 202, but also ensure the buffering performance, prevent the cover plate 2 from separating from the shell 1 in case of thermal runaway, and reduce the distance between the welding area 204 and the cover plate body 201, which indirectly reduces the distance of the cover plate 2 into the shell 1, ensuring the size of the cavity for accommodating the battery cell and ensuring the capacity of the single battery cell.

[0045] Specifically, R+h can preferably be 0.6mm, 0.7mm, 0.75mm, 0.8mm, 0.85mm or 0.9mm.

[0046] In one embodiment, the radius of curvature R ranges from 0.2 mm to 0.8 mm. If the radius of curvature R is too large, the overall height of the cover plate 2 will be too high, occupying a large space; if the radius of curvature R is too small, the intersection of the folded edge 202 and the cover plate body 201 will be similar to a right angle, which will easily cause stress concentration at the intersection of the folded edge 202 and the cover plate body 201, reducing the structural strength of the cover plate 2 and affecting its lifespan and stability.

[0047] Therefore, by keeping the radius of the arc R within the range of 0.2mm to 0.8mm, not only can the space occupied by the cover plate 2 be controlled, but stress concentration can also be avoided, thereby improving the structural strength of the cover plate 2.

[0048] Specifically, the radius R of the arc can preferably be 0.3mm, 0.4mm, 0.55mm, 0.5mm, 0.6mm, 0.65mm, 0.7mm or 0.75mm.

[0049] In one embodiment, the thickness of the arc-shaped transition portion 203 is 90% to 99% of the thickness of the folded edge 202. The reduced thickness of the arc-shaped transition portion 203 facilitates the forming of the folded edge 202, reduces processing difficulty and cost, and further provides a buffering effect, improving structural stability.

[0050] Furthermore, the thickness of the arc-shaped transition portion 203 ranges from 0.35 mm to 0.55 mm. The thickness of the arc-shaped transition portion 203 can preferably be 0.4 mm, 0.45 mm, 0.45 mm, or 0.5 mm.

[0051] In one embodiment, as shown in FIG4, the welding area 204 of the shell 1 and the folded edge 202 is spaced apart from the arc-shaped transition portion 203, that is, the welding area 204 and the transition portion 203 do not overlap. There is a gap between the arc-shaped transition portion 203 and the shell 1. In order to ensure the welding quality, the welding area 204 and the arc-shaped transition portion 203 are spaced apart, thereby ensuring the welding reliability between the shell 1 and the cover plate 2 and ensuring the overall structural strength.

[0052] In one embodiment, a pole post is provided on the cover plate 2, where 0.20 ≤ h / H ≤ 0.5. When a pole post is provided on the cover plate 2, the minimum value of h needs to be increased to reduce the impact of welding heat on the pole post, thereby ensuring the reliability of the connection between the pole post and other components. It can also avoid poor contact caused by thermal deformation of the pole post, ensuring the stability of the electrical connection and thus improving the reliability of the electrical connection.

[0053] In one embodiment, an explosion-proof valve is installed on the cover plate 2, where 0.23 ≤ h / H ≤ 0.5. When an explosion-proof valve is installed on the cover plate 2, the minimum value of h needs to be increased to reduce the impact of welding heat on the explosion-proof valve. This can reduce the risk of the explosion-proof valve being damaged due to overheating, ensure that it can work normally in an emergency, and also avoid the degradation of material properties due to thermal stress, thus reducing the risk of explosion-proof valve failure.

[0054] In one embodiment, an explosion-proof valve and a pole are provided on the cover plate 2, where 0.25 ≤ h / H ≤ 0.5. When the cover plate 2 is equipped with both a pole and an explosion-proof valve, the minimum value of h needs to be increased, which is larger than the minimum value of h when only a pole or an explosion-proof valve is provided. This can reduce the impact of welding heat on the pole and the explosion-proof valve, ensuring not only the reliability of the connection between the pole and other components, but also ensuring that the explosion-proof valve can work normally in an emergency.

[0055] In one embodiment, the sum of the heights h1 and h of the welding area 204 is 0.002 to 0.05 of the height h2 of the housing 1. The height h1 of the welding area 204 refers to the distance from the side of the welding area 204 away from the cavity to the side facing the cavity, which is the vertical dimension of the welding area 204 in Figure 4. The height of the housing 1 refers to the distance from the top end to the bottom end of the housing 1, which is the vertical dimension of the housing 1 in Figure 3.

[0056] To ensure the welding strength between the cover plate 2 and the shell 1, the welding area 204 needs to be limited. To ensure the welding strength, the welding area 204 cannot be too small. In addition, to improve the strength of the cover plate 2 and the shell 1, the range of h cannot be too small. At the same time, considering that the cover plate body 201 extends into the shell 1, the total length of the height of the welding area 204 and h cannot be too long. If it is too long, it will reduce the internal space of the shell 1 and affect the battery capacity.

[0057] Therefore, the ratio of the height h1 and the sum of the heights h1 and h2 of the welding area 204 to the height h2 of the shell 1 is in the range of 0.002 to 0.05. This not only ensures the welding strength between the cover plate 2 and the shell 1, but also makes the welding fixation between the cover plate 2 and the shell 1 more secure and reliable. In the event of thermal runaway, the cover plate 2 is less likely to separate from the shell 1, reducing safety hazards, and also reduces the impact on the capacity of the battery cell.

[0058] Specifically, the ratio of the sum of the heights h1 and h of the welding area 204 to the height h2 of the shell 1 can preferably be 0.004, 0.006, 0.008, 0.01, 0.015, 0.02, 0.025, 0.03, 0.035, 0.04 or 0.045.

[0059] Furthermore, the height h2 of the housing 1 ranges from 80mm to 250mm. The height h2 of the housing 1 cannot be too high or too low. If the height h2 of the housing 1 is too high, the taller housing 1 will lead to an increase in overall weight, which may adversely affect the user experience of portable devices and may not be suitable for application scenarios with strict size requirements. If the height h2 of the housing 1 is too low, the lower housing height means that the electrode materials that can be installed are limited, thereby limiting the maximum capacity of the battery. A lower housing may lead to an overly compact internal space, affecting heat dissipation and thus affecting the performance and lifespan of the battery. An excessively low housing may weaken its mechanical strength, making the battery more susceptible to external physical damage. A lower housing limits the flexibility of internal design and may make it difficult to optimize the internal structure of the battery to achieve optimal performance.

[0060] Therefore, the height of the casing 1 is in the range of 80mm to 250mm, which can control the weight of the casing, making it suitable for application scenarios with strict size requirements, while also ensuring the battery capacity, mechanical strength, etc., and optimizing the internal structure of the battery.

[0061] Specifically, the height of the housing 1 can preferably be 90mm, 100mm, 110mm, 120mm, 130mm, 140mm, 145mm, 150mm, 155mm, 160mm, 165mm, 170mm, 180mm, 200mm, 220mm or 240mm.

[0062] In one embodiment, the welding area 204 between the folded edge 202 and the housing 1 is located on the surface of the housing 1. The folded edge 202 is fixed to the housing 1 by through welding, which penetrates from the surface of the housing 1 to the folded edge 202 for welding. Through welding has the advantages of high-strength connection, good sealing, wide applicability, and high welding quality.

[0063] Furthermore, the welded area 204 does not penetrate the folded edge 202. This non-penetration of the welded area 204 reduces the risk of micropores or cracks caused by complete penetration welding, thereby improving the battery's sealing performance, preventing electrolyte leakage or external contaminants from entering the battery, and reducing the risk of leakage. The incomplete penetration welding preserves the integrity of the material, avoiding the material weakening that may occur with complete penetration welding, thus maintaining the structural strength of the casing 1 and the cover plate 2. It also reduces stress concentration and improves the fatigue resistance of the welded area 204.

[0064] It should be noted that welding area 204 is the gray area in Figure 4.

[0065] It is understood that, in another embodiment, the folded edge 202 and the housing 1 may also be joined by a butt weld or similar method.

[0066] In one embodiment, as shown in FIG4, the maximum depth D of the welding area 204 on the folded edge 202 is 0.2 to 0.9 of the thickness T of the folded edge 202 and the total thickness of the shell 1. The depth of the welding area 204 on the folded edge 202 refers to the depth of melting inside the folded edge along the thickness direction during welding; the depth of melting can also be referred to as the penetration depth.

[0067] Furthermore, when welding the cover and the shell 1, if the maximum depth of the welding area 204 on the fold 202 is a large proportion of the thickness of the fold 202 to the total thickness of the shell 1, it indicates that the welding area 204 extends deep into the fold 202, resulting in a significant reduction in the strength of the welding area 204. This can easily lead to local stress concentration and damage to the structural integrity of the welding area 204. Conversely, if the maximum depth of the welding area 204 on the fold 202 is a small proportion of the thickness of the fold 202 to the total thickness of the shell 1, it indicates that the welding area 204 extends shallowly into the fold 202, resulting in insufficient strength of the welding area 204 and thus affecting the overall stability and safety of the structure.

[0068] Therefore, the ratio of the maximum depth D of the welded area 204 on the folded edge 202 to the total thickness T of the folded edge 202 and the shell 1 is in the range of 0.2 to 0.9. That is, the depth of the welded area 204 extending into the folded edge 202 is within a suitable range, which ensures the strength of the welded area 204 and improves the integrity and safety of the structure.

[0069] Furthermore, when the maximum depth D of the welding area 204 on the folded edge 202 is within a certain range of the total thickness of the shell 1 (T2) and the folded edge 202, the preferred range of h+h1 is 1.2 mm to 2.0 mm.

[0070] It is worth noting that the height direction of the shell 1 refers to the up and down direction in Figure 3, and the depth direction of the welding area 204 is the thickness direction of the folded edge 202.

[0071] It should be noted that the thickness of the folded edge 202 can be equal to the thickness of the cover plate body 201, or it can be less than or equal to the thickness of the cover plate body 201. The thickness of the folded edge 202 and the thickness of the cover plate body 201 need to be set according to the specific situation.

[0072] In one embodiment, the battery casing is made of stainless steel, that is, both the cover plate 2 and the casing 1 are made of stainless steel. Stainless steel has advantages such as good corrosion resistance, high strength, excellent thermal expansion and insulation properties, good impermeability, good safety, and weldability.

[0073] It is understood that, in another embodiment, the battery casing may be made of other materials, and is not limited to this.

[0074] In one embodiment, the cover plate body 201 and the folded edge 202 are formed by bending a single sheet of material. The cover plate 2 is manufactured from the sheet material, which simplifies the manufacturing process and reduces manufacturing costs. If the thickness of the sheet material is uniform throughout, the thickness of the folded edge 202 formed by bending the edge of the sheet material is the same as the thickness of the cover plate body 201. If the thickness of the sheet material is gradually varying, the thickness of the folded edge 202 is different from the thickness of the cover plate body 201.

[0075] It is understood that, in another embodiment, the cover body 201 and the folded edge 202 can also be formed and fixedly connected separately.

[0076] In one embodiment, the folded edge 202 is provided around the cover plate body 201. The folded edge 202 is interference-fitted with the inner wall of the housing 1, which can facilitate welding the housing 1 and the cover plate 2 together by through welding, thereby improving welding efficiency.

[0077] According to an embodiment of this application, another aspect provides a battery, including: the battery casing described above, and a battery cell disposed within a receiving cavity of the battery casing.

[0078] Furthermore, the battery cell can be a wound battery cell or a stacked battery cell, and the terminals can be set on the battery casing or on the cover plate body 201. The terminals and the battery cell's tabs are connected together by connecting pieces.

[0079] It should be noted that the battery cells, terminals, etc., can all use the existing structures, and will not be described in detail here.

[0080] According to an embodiment of this application, in another aspect, a battery pack is also provided, including the battery described above.

[0081] Furthermore, a battery pack combines multiple batteries and their related components to form a complete energy storage unit. The design and structure of a battery pack typically need to consider multiple factors, including but not limited to safety, reliability, thermal management, and electrical connections.

[0082] Specifically, a battery pack also includes a battery housing, a battery management system, a thermal management system, and so on. The battery housing houses the batteries, while the battery management system monitors and manages the battery status, such as voltage, current, and temperature, to ensure safe and efficient operation. It also balances the batteries and prevents individual batteries from being overcharged or over-discharged. The thermal management system maintains the battery pack within an optimal operating temperature range, typically achieved through a cooling or heating system, which helps improve battery life and safety.

[0083] 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 casing, characterized in that, include: The shell (1) has an opening; A cover plate (2) seals the opening to form a receiving cavity. The cover plate (2) includes a cover plate body (201) and a flange (202) disposed on the edge of the cover plate body (201). The flange (202) extends in a direction away from the receiving cavity. The flange (202) is welded to the housing (1). The welded part of the flange (202) and the housing (1) forms a welding area (204). In the extension direction of the flange (202), the cover plate body (201) is located on the side of the welding area (204) close to the receiving cavity. In a direction perpendicular to the upper surface of the cover plate body (201), the distance from the side of the welding area (204) close to the receiving cavity to the upper surface of the cover plate body (201) is h. The distance from the side of the flange (202) away from the receiving cavity to the side of the cover plate body (201) close to the receiving cavity is H. Wherein, 0.17≤h / H≤0.5; The range of h is 0.1 mm to 1 mm, and the range of H is 0.5 mm to 4 mm.

2. The battery casing according to claim 1, characterized in that, The ratio of the thickness T1 of the folded edge (202) to the thickness T2 of the shell (1) is 1.2:1 to 3:

1.

3. The battery casing according to claim 1, characterized in that, The top of the opening of the housing (1) is not higher than the top of the fold (202).

4. The battery casing according to claim 3, characterized in that, The top of the opening of the housing (1) is lower than the top of the flange (202).

5. The battery casing according to claim 4, characterized in that, 0.17≤h / H≤0.

35.

6. The battery casing according to claim 1, characterized in that, The cover plate body (201) and the folded edge (202) are connected by an arc-shaped transition part (203), and the arc radius R of the arc-shaped transition part (203) and the h satisfy the relationship: 0.5mm≤R+h≤1mm.

7. The battery casing according to claim 6, characterized in that, The radius R of the arc is in the range of 0.2mm to 0.8mm.

8. The battery casing according to claim 6, characterized in that, The thickness of the arc-shaped transition portion (203) is 90% to 99% of the thickness of the folded edge (202).

9. The battery casing according to claim 6, characterized in that, The welding area (204) of the shell (1) and the folded edge (202) is spaced apart from the arc-shaped transition portion (203).

10. The battery casing according to claim 1, characterized in that, The cover plate (2) is provided with poles, 0.20≤h / H≤0.

5.

11. The battery casing according to claim 1, characterized in that, An explosion-proof valve is installed on the cover plate (2), with a value of 0.23 ≤ h / H ≤ 0.

5.

12. The battery casing according to claim 1, characterized in that, An explosion-proof valve and a pole are provided on the cover plate (2), with a value of 0.25 ≤ h / H ≤ 0.

5.

13. The battery casing according to claim 1, characterized in that, The ratio of the height h1 of the welding area (204) and the sum of h to the height h2 of the shell (1) is 0.002 to 0.

05.

14. The battery casing according to claim 1, characterized in that, The welded area (204) of the flange (202) and the housing (1) is located on the surface of the housing (1).

15. A battery, characterized in that, include: The battery casing and the battery cell according to any one of claims 1 to 14, wherein the battery cell is disposed within a receiving cavity of the battery casing.

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