Battery case, battery cell, battery pack, and electric device

Abstract

Embodiments of the present disclosure provide a battery shell, a battery monomer, a battery pack and an electric device. The present disclosure relates to the technical field of batteries. The battery shell comprises a shell body and a cover plate. The shell body has a first wall surface and a second wall surface oppositely arranged in a second direction. A first extension cavity and a second extension cavity are formed on the inner side of the first wall surface. A first protrusion and a second protrusion are correspondingly formed on the outer wall surface of the first wall surface. An accommodation groove is formed between the first protrusion and the second protrusion. A part of the second wall surface protrudes towards the outer side of the accommodation cavity to form a limiting protrusion. The projection of the limiting protrusion falls into the accommodation groove in the second direction. The width of the accommodation groove is greater than the sum of the widths of the first protrusion and the second protrusion in the third direction. Therefore, the battery shell of the embodiments of the present disclosure has the advantages of high structural strength, good stability and long service life.

Description

Technical Field

[0001] This disclosure relates to the field of battery technology, specifically to a battery casing and a battery cell, battery pack, and electrical device having the battery casing. Background Technology

[0002] The key to the development of battery technology lies in electrochemical energy storage technology. Due to its advantages such as high energy density, good cycle life, high operating voltage, environmental friendliness, and low self-discharge, it has been widely used in portable electronics, electric vehicles, and energy storage systems. A battery pack includes at least one battery cell. During multiple charge-discharge cycles, gas is generated inside the battery cell due to side reactions of the electrochemical reaction. As the gas content increases, the gas pressure inside the battery casing also increases. If the gas cannot be effectively guided to the outside of the battery casing, it can easily reduce the lifespan of the battery pack.

[0003] In related technologies, protrusions and corresponding grooves are set on the side wall of the casing to solve the problem that the expansion of the battery cell causes blockage of the exhaust channel, resulting in the inability of gas inside the casing to be discharged. However, if the protrusions are not set properly, it can easily cause difficulties in lithium-ion transport and thus lead to lithium plating problems. Utility Model Content

[0004] In view of this, the present disclosure aims to provide a battery casing, a battery cell, a battery pack, and an electrical device to solve the problem of lithium plating in battery cells caused by unreasonable battery casing structure in the prior art.

[0005] This disclosure provides a battery housing. The battery housing includes a housing body and a cover plate. The housing body has a receiving cavity, and the housing body has an opening at at least one end in a first direction. The housing body has a first wall and a second wall disposed opposite to each other in a second direction. At least two portions of the first wall protrude outward from the receiving cavity relative to the remaining portions to form a first expansion cavity and a second expansion cavity on the inner side of the first wall. A first protrusion and a second protrusion are correspondingly formed on the outer wall of the first wall, and the first protrusion and the second protrusion are spaced apart in a third direction to form a receiving groove between the first protrusion and the second protrusion. A portion of the second wall protrudes outward from the receiving cavity relative to the remaining portions to form a limiting protrusion. Along the second direction, the projections of the limiting protrusions all fall into the receiving groove, and in the third direction, the width of the receiving groove is greater than the sum of the widths of the first protrusion and the second protrusion. The first direction, the second direction, and the third direction are perpendicular to each other. The cover plate is fitted and connected to the opening of the housing body.

[0006] In another aspect, this disclosure provides a battery cell.

[0007] This disclosure also provides a battery pack.

[0008] This disclosure also provides an electrical appliance.

[0009] The battery casing of the above-mentioned technical solution, by forming a first expansion cavity and a second expansion cavity on the inner sidewall of the first wall of the casing body, can accommodate the gas generated during the cell's cycling due to side reactions of electrochemical reactions. This mitigates the risk of gas inside the battery casing being unable to escape due to deformation blocking the exhaust channel in the middle region of the cell, thereby improving the risk of damage to the battery cell's performance caused by excessive gas accumulation inside the battery casing. With a fixed battery casing length, a larger width of the first and second protrusions means a smaller accommodating groove width. The battery casing of this embodiment avoids the problem of lithium plating caused by a small accommodating groove width, which would result in a small contact area with the expanded cell, leading to excessive local pressure and difficulty in lithium-ion transport in that part of the cell. Therefore, by reasonably limiting the width of the accommodating groove, lithium plating can be avoided, improving the battery cell's lifespan. Thus, the battery casing of this embodiment combines high structural strength, good stability, long service life, and avoidance of lithium plating. Attached Figure Description

[0010] It should be understood that the following figures only illustrate certain embodiments of this disclosure and should not be construed as limiting the scope.

[0011] It should be understood that the same or similar reference numerals are used in the accompanying drawings to denote the same or similar elements.

[0012] It should be understood that the accompanying drawings are only schematic, and the dimensions and scales of the elements in the drawings are not necessarily precise.

[0013] Figure 1 This is a perspective view of a battery cell according to an embodiment of the present disclosure.

[0014] Figure 2 This is another perspective view of a battery cell according to an embodiment of the present disclosure.

[0015] Figure 3 This is a bottom view of a battery cell according to an embodiment of this disclosure.

[0016] Figure 4 This is an exploded view of a battery cell according to an embodiment of this disclosure.

[0017] Figure 5 This is another exploded view of a battery cell according to an embodiment of this disclosure.

[0018] Figure 6 This is a perspective view of the shell body according to an embodiment of the present disclosure.

[0019] Figure 7 This is another perspective view of the shell body according to an embodiment of this disclosure.

[0020] Figure 8 This is a schematic diagram of multiple battery cells stacked in a battery pack according to an embodiment of this disclosure.

[0021] Explanation of reference numerals in the attached figures: Battery casing 100; battery cell 200; Shell body 1; receiving cavity 11; opening 12; first wall surface 13; first protrusion 131; second protrusion 132; receiving groove 133; first expansion cavity 134; second expansion cavity 135; Second wall surface 14; Limiting protrusion 141; Cover plate 2. Detailed Implementation

[0022] The technical solutions of the present disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present disclosure, and not all embodiments.

[0023] During battery charging and discharging, the expansion and contraction of the electrode components generate periodic stress on the casing. In related technologies, protrusions and corresponding grooves are provided on the side wall of the casing body 1 to solve the problem that the expansion of the cell 200 causes blockage of the exhaust channel, preventing the gas inside the casing body 1 from being discharged. However, the width of the groove is not set reasonably, which can easily cause difficulties in lithium-ion transport and thus lead to lithium plating problems.

[0024] To address this issue, the battery cell assembly of this disclosure incorporates a first protrusion 131, a second protrusion 132, and a receiving groove 133 formed between the two on the first wall surface 13, and a limiting protrusion 141 on the second wall surface 14. The width of the receiving groove 133 is greater than the sum of the widths of the first protrusion 131 and the second protrusion 132, effectively solving the aforementioned technical problem. Specifically, by making the width of the receiving groove 133 greater than the sum of the widths of the first protrusion 131 and the second protrusion 132, the problem of lithium plating caused by an excessively small width of the receiving groove 133, resulting in a small contact area with the expanded cell 200, and consequently excessive local pressure, is avoided. This prevents lithium ion transport difficulties in that portion of the cell 200, thus improving the battery cell's lifespan. Therefore, by reasonably limiting the width of the receiving groove 133, lithium plating can be avoided, improving the battery cell's lifespan.

[0025] The disclosed battery pack includes a battery pack composed of multiple battery cells connected in series and / or in parallel to form a battery management system (BMS), a thermal management system, an electrical connection system (high-voltage / low-voltage connectors, wiring harnesses, etc.), structural components (shell, brackets, etc.), and protective components, etc., and the above components are placed in a box and sealed by a cover plate 2 to form a complete functional unit that can directly output electrical energy.

[0026] In this embodiment of the disclosure, the battery cell can be a secondary battery, which refers to a battery cell that can be recharged to activate the active materials and continue to be used after the battery cell has been discharged.

[0027] The battery apparatus mentioned in the embodiments of this disclosure may include one or more battery cells for providing voltage and capacity. A battery cell assembly may include multiple battery cells connected in series, parallel, or a combination of these cells via a busbar. Battery cells may be, but are not limited to, lithium-ion batteries, sodium-ion batteries, sodium-lithium-ion batteries, lithium metal batteries, sodium metal batteries, lithium-sulfur batteries, magnesium-ion batteries, nickel-metal hydride batteries, nickel-cadmium batteries, lead-acid batteries, etc. A battery cell generally includes an electrode assembly. The electrode assembly includes a positive electrode, a negative electrode, and a separator. During the charging and discharging process of the battery cell, active ions (e.g., lithium ions) repeatedly insert and extract between the positive and negative electrodes. The separator, located between the positive and negative electrodes, prevents short circuits between the electrodes while allowing active ions to pass through.

[0028] The aforementioned battery cell refers to a battery that can store chemical energy and controllably convert it into electrical energy. In recyclable batteries, the active materials can be reactivated by charging after discharge, allowing for continued use. A battery cell typically includes a casing and electrode assemblies housed within the casing.

[0029] The following is for reference. Figures 1-8 The present disclosure provides examples of the battery casing 100, battery cell, battery pack, and electrical equipment according to embodiments thereof.

[0030] The battery casing 100 of this embodiment includes a casing body 1 and a cover plate 2.

[0031] The shell body 1 has a receiving cavity 11, and the shell body 1 is in a first direction (e.g., Figure 1 At least one end of the shell body 1 in the vertical direction (i.e., the height direction of the shell) has an opening 12, and the shell body 1 in the second direction (e.g., Figure 1The front-to-back direction (i.e., the thickness direction of the housing) shown has a first wall surface 13 and a second wall surface 14 disposed opposite to each other. At least two portions of the first wall surface 13 protrude outward toward the outer side of the receiving cavity 11 relative to the remaining portions, so as to form a first expansion cavity 134 and a second expansion cavity 135 on the inner side of the first wall surface 13, and a first protrusion 131 and a second protrusion 132 are correspondingly formed on the outer wall surface of the first wall surface 13, and the first protrusion 131 and the second protrusion 132 are in a third direction (e.g., Figure 1 The protrusions (shown in the left-right direction, i.e., the length direction of the shell) are spaced apart to form a receiving groove 133 between the first protrusion 131 and the second protrusion 132. A portion of the second wall surface 14 protrudes outward relative to the rest toward the outside of the receiving cavity 11 to form a limiting protrusion 141. Along the second direction, the projections of the limiting protrusions 141 all fall into the receiving groove 133, and in the third direction, the width of the receiving groove 133 is greater than the sum of the widths of the first protrusion 131 and the second protrusion 132. The first direction, the second direction, and the third direction are arranged perpendicular to each other. The cover plate 2 is fitted and connected to the opening 12 of the shell body 1. It can be understood that the width of the receiving groove 133 is the distance between the first protrusion 131 and the second protrusion 132.

[0032] The battery casing 100 of this embodiment, by forming a first expansion cavity 134 and a second expansion cavity 135 on the inner sidewall of the first wall surface 13 of the casing body 1, can accommodate the gas generated by the side reaction of the electrochemical reaction that may occur during the cycling of the battery cell 200. This mitigates the risk that the gas inside the battery casing 100 cannot be discharged due to the deformation of the middle region of the battery cell 200 blocking the exhaust channel, thereby improving the risk of damage to the performance of the battery cell due to the accumulation of too much gas inside the battery casing 100.

[0033] Furthermore, given a fixed length of the battery casing 100, a larger width for the first protrusion 131 and the second protrusion 132 implies a smaller width for the receiving groove 133. In this embodiment of the battery casing 100, by making the width of the receiving groove 133 greater than the sum of the widths of the first protrusion 131 and the second protrusion 132, the problem of lithium plating caused by an excessively small width of the receiving groove 133, resulting in a small contact area with the expanded battery cell 200, and consequently excessive local pressure, is avoided. Thus, by reasonably limiting the width of the receiving groove 133, lithium plating can be avoided, improving the lifespan of the battery cell.

[0034] Meanwhile, the first protrusion 131 and the second protrusion 132 on the first wall 13, as well as the limiting protrusion 141 on the second wall 14, can enhance the structural strength of the shell body 1. The receiving groove 133 formed between the first protrusion 131 and the second protrusion 132 can accommodate the limiting protrusion 141 of adjacent battery cells when multiple battery cells are stacked. This not only achieves precise positioning and stable stacking of battery cells, improving the overall stability and safety of the battery pack, but also increases the energy density of the battery pack.

[0035] Therefore, the battery casing 100 of this embodiment has the advantages of high structural strength, good stability and long service life, and avoids the problem of lithium plating.

[0036] Optionally, the casing body 1 and the cover plate 2 can be made of common metal or plastic materials, processed by stamping, injection molding, or other processes, and then the cover plate 2 is fixed to the opening 12 of the casing body 1 by a cover-fitting connection to form a complete battery casing 100. For example, the cover plate 2 and the casing body 1 can be fitted together by welding, snap-fitting, or threaded connection.

[0037] like Figure 2 , Figure 4 and Figure 5 As shown, the first protrusion 131 and the second protrusion 132 are parallel and extend along the first direction.

[0038] The battery casing 100 of this embodiment, by arranging the first protrusion 131 and the second protrusion 132 parallel and extending along a first direction, facilitates the stacking of adjacent battery cells during cell stacking. Since the cover plate 2 typically has a first direction, ions in the cell 200 are transported along this first direction during charging and discharging. Arranging the first protrusion 131 and the second protrusion 132 parallel and extending along the first direction does not obstruct ion transport within the cell 200, thus promoting smooth ion transport and further preventing lithium plating problems caused by obstructed ion transport.

[0039] Furthermore, the shapes of the limiting protrusion 141, the first protrusion 131, and the second protrusion 132 can be selected according to specific design requirements. The limiting protrusion 141, the first protrusion 131, and the second protrusion 132 can be designed as rectangular, trapezoidal, semi-circular, or irregular structures, etc. When the limiting protrusion 141, the first protrusion 131, and the second protrusion 132 are designed as rectangular, their structure is simple and easy to process, and they can provide a relatively stable limiting effect when stacked. When the limiting protrusion 141, the first protrusion 131, and the second protrusion 132 are designed as trapezoidal, their upper base size is smaller and their lower base size is larger, which allows for smoother stacking.

[0040] like Figure 2 , Figure 4 and Figure 5 As shown, the first wall surface 13 of the shell body 1 has a center line in a third direction, and the first protrusion 131 and the second protrusion 132 are symmetrically arranged relative to the center line.

[0041] The battery casing 100 of this embodiment, by symmetrically arranging the first protrusion 131 and the second protrusion 132 relative to the center line, ensures more balanced venting of the battery cell 200 during charging and discharging, avoiding performance degradation caused by poor venting on one side. Furthermore, it allows the battery cell 200 to experience more uniform constraint from the casing body 1 in a third direction during expansion, reducing the risk of damage to the battery cell 200 due to uneven local stress. This, in turn, improves the overall structural stability of the battery cell. Simultaneously, this symmetrical structure also ensures more balanced stress between adjacent battery cells during stacking, enhancing the overall stability and reliability of the battery pack.

[0042] In the first direction, the edge of the first protrusion 131 is spaced apart from the cover plate 2, with a minimum distance of 5mm-20mm.

[0043] The battery casing 100 of this embodiment, by reasonably setting the spacing between the edge of the first protrusion 131 and the cover plate 2 in the first direction, helps to provide a certain buffer space during the thermal expansion of the battery cell, preventing damage due to excessive compression between components. This is particularly important for preventing cracking of the weld lines between the cover plate 2 and the casing body 1. Furthermore, it allows the discharged gas to be contained within the first expansion cavity 134 and the second expansion cavity 135, avoiding direct impact on the cover plate 2, which could cause deformation or damage due to gas impact, thereby ensuring the safety and stability of the battery cell.

[0044] Optionally, the minimum distance between the edge of the first protrusion 131 and the cover plate 2 can be 5mm, 8mm, 10mm, 12mm, 14mm, 15mm, 17mm, 19mm and 20mm, as well as a range between any two point values.

[0045] Accordingly, in the first direction, the second protrusion 132 is spaced apart from the cover plate 2, with a minimum distance of 5mm-20mm. Similarly, this structural arrangement has the advantage of improving the service life of individual battery cells.

[0046] Optionally, the minimum distance between the edge of the second protrusion 132 and the cover plate 2 can be 5mm, 8mm, 10mm, 12mm, 14mm, 15mm, 17mm, 19mm and 20mm, as well as a range of values ​​between any two points.

[0047] like Figure 8As shown, in the second direction, the height of the first protrusion 131 and the second protrusion 132 protruding relative to the shell body 1 is greater than or equal to the height of the limiting protrusion 141 protruding relative to the shell body 1.

[0048] The battery casing 100 of this embodiment limits the height of the first protrusion 131 and the second protrusion 132 relative to the casing body 1 to be greater than or equal to the height of the limiting protrusion 141 relative to the casing body 1. When multiple battery cells are stacked, the receiving groove 133 formed between the first protrusion 131 and the second protrusion 132 can better cooperate with the limiting protrusion 141 of adjacent battery cells. This avoids the limiting protrusion 141 from not falling completely into the receiving groove 133 during stacking due to excessive protrusion height. Even if the battery cell 200 expands to a certain extent, the limiting protrusion 141 can still maintain a relatively stable position within the receiving groove 133 and will not detach from the receiving groove 133 due to the expansion of the battery cell 200, thereby ensuring the reliability of the connection between battery cells.

[0049] Furthermore, the difference between the height of the first protrusion 131 and the second protrusion 132 protruding relative to the shell body 1 and the height of the limiting protrusion 141 protruding relative to the shell body 1 is 0.1mm-0.2mm.

[0050] The battery casing 100 of this embodiment, by limiting the aforementioned difference range, avoids the difference from becoming too large. The limiting protrusion 141 in the receiving groove 133 fails to limit the movement of the receiving protrusion 141 within the receiving groove 133, resulting in excessive vertical movement and insufficient restraint on the vertical (Z-axis) displacement of adjacent batteries. This can easily lead to micro-wear, abnormal noise, and even loosening of connections under vehicle vibration or impact. Furthermore, an excessively large difference in height also results in poor structural compactness of the battery cells. On the one hand, if the difference is too small (i.e., the height of the limiting protrusion 141 is greater than or equal to the depth of the receiving groove 133), physical obstruction will occur, preventing adjacent battery cells from being properly inserted. Forced insertion would cause additional compression of the cell 200, leading to safety risks (internal short circuit, bulging). Simultaneously, the battery's heat and expansion during operation could compress the cell 200, affecting cycle life. Therefore, a reasonable height difference balances both structural compactness and long service life.

[0051] Optionally, the difference between the height of the first protrusion 131 and the second protrusion 132 protruding relative to the shell body 1 and the height of the limiting protrusion 141 protruding relative to the shell body 1 can be 0.10mm, 0.12mm, 0.14mm, 0.15mm, 0.16mm, 0.18mm and 0.20mm.

[0052] In the second direction, the first protrusion 131 protrudes 0.5mm-1mm above the shell body 1.

[0053] The battery casing 100 of this embodiment controls the height range of the first protrusion 131 relative to the casing body 1 to ensure that a sufficiently large expansion cavity is formed to accommodate the gas generated by the electrochemical reaction, further avoiding the risk of damage to the performance of the battery cells due to excessive gas accumulation inside the battery casing 100. On the other hand... This design ensures that the limiting protrusion 141 provides sufficient depth for the battery cell stacking, guaranteeing the stability of the stack and preventing loosening or misalignment. Therefore, by appropriately setting the height range of the first protrusion 131 relative to the shell body 1, both improved service life and structural stability can be achieved.

[0054] Optionally, the height of the first protrusion 131 protruding relative to the shell body 1 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm and 1.0mm.

[0055] In the second direction, the second protrusion 132 protrudes 0.5mm-1mm above the shell body 1. Similarly, it combines the advantages of increased service life and good structural stability. Optionally, the height of the second protrusion 132 protruding relative to the shell body 1 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm and 1.0mm.

[0056] In the third direction, the distance between the center line of the first protrusion 131 and the center line of the second protrusion 132 is 100mm-280mm.

[0057] The battery casing 100 of this embodiment defines the distance range between the center lines of the first protrusion 131 and the second protrusion 132, and combines this with the fact that the width of the receiving groove 133 is greater than the sum of the widths of the first protrusion 131 and the second protrusion 132. This makes the positioning of adjacent battery cells in the third direction more accurate, reducing the problem of local stress concentration caused by positional deviation. When the battery cells expand during charging and discharging, the reasonable setting of the distance between the center lines of the first protrusion 131 and the second protrusion 132 ensures that the receiving groove 133 effectively constrains the limiting protrusion 141, preventing relative displacement between battery cells, thereby improving the overall structural strength and stability of the battery pack.

[0058] Optionally, the distance between the center line of the first protrusion 131 and the center line of the second protrusion 132 can be 100mm, 110mm, 130mm, 150mm, 170mm, 190mm, 210mm, 230mm, 250mm, 260mm, 270mm and 280mm, as well as a range between any two point values.

[0059] In the third direction, the offset distance between the center line of the limiting protrusion 141 and the center line of the shell body 1 is less than 1mm.

[0060] The battery housing 100 of this embodiment ensures that the limiting protrusion 141 accurately falls into the receiving groove 133 of adjacent battery cells when the battery cells are stacked by offsetting the center line of the limiting protrusion 141 relative to the center line of the housing body 1 by a distance less than a specific value. This also improves the overall structural compactness of the battery pack, allowing it to accommodate more battery cells within a limited space, thereby increasing the energy density of the battery pack. Simultaneously, this offset distance also helps improve the overall structural symmetry of the battery pack, reducing stress concentration problems caused by structural asymmetry, thus improving the safety and reliability of the battery pack.

[0061] Optionally, the offset distance of the limiting protrusion 141 relative to the center line of the shell body 1 can be 0 mm, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm and 0.99 mm, as well as a range between any two point values.

[0062] The shell body 1 has a third wall and a fourth wall that are arranged opposite to each other in the third direction. A first protrusion 131 is arranged close to the third wall, and a second protrusion 132 is arranged close to the fourth wall. The distance between the first protrusion 131 and the third wall is 10mm-50mm, and the distance between the second protrusion 132 and the fourth wall is 10mm-50mm.

[0063] The battery casing 100 of this embodiment, by placing the first protrusion 131 and the second protrusion 132 close to the third and fourth wall surfaces of the casing body 1 respectively, ensures that the receiving groove 133 has sufficient width while maintaining a fixed length of the battery cell. This avoids the problem of lithium plating caused by excessive local pressure due to the small contact area between the receiving groove 133 and the expanded battery cell 200, resulting in difficulty in lithium ion transport. Therefore, the battery cell lifespan is improved.

[0064] Optionally, the distance between the first protrusion 131 and the third wall can be 10mm, 12mm, 14mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm, 30mm, 32mm, 35mm, 38mm, 40mm, 43mm, 46mm, 50mm, or any range between any two points.

[0065] Optionally, the distance between the second protrusion 132 and the fourth wall can be 10mm, 12mm, 14mm, 15mm, 18mm, 20mm, 22mm, 25mm, 28mm, 30mm, 32mm, 35mm, 38mm, 40mm, 43mm, 46mm, 50mm, or any range between any two points.

[0066] In the third direction, the ratio of the sum of the widths of the first protrusion 131 and the second protrusion 132 to the width of the shell body 1 in the third direction is 0.2-0.5.

[0067] The battery casing 100 of this embodiment, by reasonably setting the ratio range of the sum of the widths of the first protrusion 131 and the second protrusion 132 to the width of the casing body 1 in the third direction, ensures both the capacity of the expansion cavity formed by the first protrusion 131 and the second protrusion 132 and the structural compactness of the battery cell in the third direction. When this ratio is set too large, although the capacity of the expansion cavity increases, it will lead to an excessively large size of the battery cell in the third direction, affecting the overall structural compactness and energy density of the battery pack. When this ratio is set too small, the capacity of the expansion cavity may be insufficient to effectively accommodate the gas generated by the electrochemical reaction, thereby affecting the performance of the battery cell. Therefore, reasonably setting this ratio range can balance the capacity of the expansion cavity and the structural compactness, thereby improving the service life of the battery cell and the overall performance of the battery pack.

[0068] Optionally, the ratio of the sum of the widths of the first protrusion 131 and the second protrusion 132 to the width of the shell body 1 in a third direction can be 0.20, 0.25, 0.30, 0.35, 0.40, 0.45 and 0.50, as well as a range between any two point values.

[0069] In the first direction, the ratio of the height of the limiting protrusion 141 to the height of the shell body 1 is 0.5-0.9.

[0070] The battery casing 100 of this embodiment addresses this issue by reasonably setting the ratio range between the height of the limiting protrusion 141 and the height of the casing body 1. If this ratio is too large, it indicates that the height of the limiting protrusion 141 is too large, which will affect the connection between the cover plate 2 and the casing body 1 during expansion. Conversely, if the limiting protrusion 141 is too large, it means that the distance between the cover plate 2 and the casing body 1 is too small, which can lead to cracking of the weld lines between the cover plate 2 and the casing body 1. If the ratio is too small, the expansion cavity formed by the limiting protrusion 141 cannot accommodate a sufficient amount of gas generated by the electrochemical reaction, thus affecting the performance of the battery cells. Therefore, reasonably setting this height ratio range can balance the expansion cavity capacity, service life, and overall structural stability.

[0071] Optionally, in the first direction, the ratio of the height of the limiting protrusion 141 to the height of the shell body 1 can be 0.5, 0.6, 0.7, 0.8 and 0.9, or a range between any two points.

[0072] In the first direction, the limiting protrusion 141 and the cover plate 2 are spaced apart, with a minimum spacing of 5mm-20mm.

[0073] The battery casing 100 of this embodiment effectively prevents the cover plate 2 from being squeezed due to the expansion of the battery cell 200 during charging and discharging by reasonably setting the minimum gap between the limiting protrusion 141 and the cover plate 2 in the first direction, thus preventing the cover plate 2 from deforming or being damaged, and ensuring the sealing and safety of the battery interior. It also avoids the gap being too small, which would reduce the applicability of the cover plate 2 and the casing body 1. When the gap is within a suitable range, it provides sufficient gas storage space for the gas production of the battery cell 200 while preventing the battery casing 100 from cracking, thereby improving the overall structural stability of the battery.

[0074] Optionally, the minimum spacing between the limiting protrusion 141 and the cover plate 2 is 5mm, 8mm, 10mm, 12mm, 14mm, 15mm, 17mm, 19mm and 20mm, as well as the range between any two points. The specific values ​​can be flexibly adjusted according to the battery design parameters and actual usage requirements to meet the performance requirements in different scenarios.

[0075] In the third direction, the difference between the width of the limiting protrusion 141 and the width of the receiving groove 133 is 0.1mm-0.2mm.

[0076] The battery housing 100 of this embodiment achieves precise positioning and fit during battery cell stacking by reasonably setting the difference range between the width of the limiting protrusion 141 and the width of the receiving groove 133, ensuring the compactness and stability of the overall battery pack structure. When the difference is within a suitable range, the limiting protrusion 141 can smoothly embed into the receiving groove 133, avoiding assembly difficulties or even failure to embed due to an excessively small difference, and also preventing excessive gaps that could affect the stacking stability of the battery cells. A suitable difference also ensures that there is adequate movement allowance between the limiting protrusion 141 and the receiving groove 133 during battery cell operation to accommodate the slight expansion and contraction of the cell 200, while avoiding abnormal friction and wear between components caused by excessive gaps.

[0077] Optionally, in a third direction, the difference between the width of the limiting protrusion 141 and the width of the receiving groove 133 is 0.10 mm, 0.12 mm, 0.14 mm, 0.15 mm, 0.16 mm, 0.18 mm, and 0.20 mm.

[0078] The area of ​​the first wall surface 13 of the shell body 1 is larger than the area of ​​the remaining surfaces adjacent to the first wall surface 13.

[0079] The battery casing 100 of this embodiment features a first wall surface 13 with an area larger than the adjacent surfaces of the casing body 1. This means that the first protrusion 131 and the second protrusion 132 are both located on the larger surface of the casing body 1. This design fully utilizes the large surface space of the casing body 1, ensuring the overall compactness of the battery cell structure while providing sufficient area for the first protrusion 131 and the second protrusion 132, allowing for a more rational layout of the receiving groove 133. Furthermore, the larger area of ​​the first wall surface 13 better disperses the stress generated by the expansion of the cell 200 during battery cell operation, avoiding localized stress concentration and reducing the risk of battery cell damage, thereby further improving the reliability and lifespan of the battery cell. Simultaneously, this design also facilitates the arrangement and assembly of battery cells within the battery pack, improving the space utilization and overall performance of the battery pack.

[0080] Optionally, the shell body 1 can be made of various materials, such as the common aluminum alloy, which has advantages such as light weight, high strength, and good corrosion resistance, effectively reducing the overall weight of the battery shell 100 while ensuring stable use in various complex environments and providing reliable protection for the battery cells. It can also be made of steel, which has extremely high strength and can withstand significant external impacts, performing excellently in applications with extremely demanding mechanical strength requirements; however, its weight is relatively greater than that of aluminum alloy. The shape of the shell body 1 can be cylindrical, cuboid, or cube, etc.

[0081] like Figures 1 to 4 As shown, the battery cell of this embodiment includes a cell 200 and a battery casing 100 as described above, wherein the cell 200 is disposed in the receiving cavity 11 of the battery casing 100.

[0082] Therefore, the battery cells of the present disclosure have high structural strength, good stability and long service life, and avoid the problem of lithium plating.

[0083] Furthermore, the battery pack of this embodiment may include at least two of the above-mentioned battery cells, and the limiting protrusions 141 of two adjacent shell bodies 1 are engaged in the receiving grooves 133 of the shell bodies 1 adjacent to them.

[0084] Therefore, the embodiments of this disclosure have the advantage of improving the structural stability and safety of battery cells.

[0085] This disclosure also provides an electrical device including the battery pack described above. This disclosure provides an electrical device that uses the electrical device as a power source. The electrical device can be, but is not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric bicycles, electric motorcycles, electric cars, ships, spacecraft, etc. Among them, electric toys can include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc., and spacecraft can include airplanes, rockets, space shuttles, and spacecraft, etc.

[0086] The above description is merely a preferred embodiment of this disclosure and is not intended to limit this disclosure. Any modifications or equivalent substitutions made within the spirit and principles of this disclosure should be included within the scope of protection of this disclosure.

[0087] In the description of this disclosure, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this disclosure and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this disclosure.

[0088] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this disclosure, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0089] In this disclosure, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this disclosure according to the specific circumstances.

[0090] In this disclosure, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0091] In this disclosure, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0092] Although embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A battery casing, characterized in that, include: A shell body has a receiving cavity. The shell body has an opening at at least one end in a first direction. The shell body has a first wall and a second wall disposed opposite to each other in a second direction. At least two portions of the first wall protrude outward toward the outside of the receiving cavity relative to the remaining portions to form a first expansion cavity and a second expansion cavity on the inner side of the first wall. A first protrusion and a second protrusion are correspondingly formed on the outer wall of the first wall. The first protrusion and the second protrusion are spaced apart in a third direction to form a receiving groove between the first protrusion and the second protrusion. A portion of the second wall protrudes outward toward the outside of the receiving cavity relative to the remaining portions to form a limiting protrusion. Along the second direction, the projections of the limiting protrusions all fall into the receiving groove. In the third direction, the width of the receiving groove is greater than the sum of the widths of the first protrusion and the second protrusion. The first direction, the second direction, and the third direction are perpendicular to each other. A cover plate that covers the opening of the shell body.

2. The battery casing according to claim 1, characterized in that, The first protrusion and the second protrusion are parallel and extend along the first direction.

3. The battery casing according to claim 1, characterized in that, The first wall of the shell body has a center line in the third direction, and the first protrusion and the second protrusion are symmetrically arranged relative to the center line.

4. The battery casing according to claim 1, characterized in that, In the first direction, the edge of the first protrusion is spaced apart from the cover plate, with a minimum distance of 5mm-20mm. And / or, in the first direction, the second protrusion is spaced apart from the cover plate, with a minimum distance of 5mm-20mm between them.

5. The battery casing according to claim 1, characterized in that, In the second direction, the height by which the first protrusion and the second protrusion protrude relative to the shell body is greater than or equal to the height by which the limiting protrusion protrudes relative to the shell body.

6. The battery casing according to claim 5, characterized in that, The difference between the height of the first protrusion and the second protrusion relative to the shell body and the height of the limiting protrusion relative to the shell body is 0.1mm-0.2mm.

7. The battery casing according to claim 5, characterized in that, In the second direction, the height of the first protrusion relative to the shell body is 0.5mm-1mm; And / or, in the second direction, the second protrusion protrudes 0.5mm-1mm relative to the shell body.

8. The battery casing according to claim 1, characterized in that, In the third direction, the distance between the center line of the first protrusion and the center line of the second protrusion is 100mm-280mm; And / or, in the third direction, the offset distance of the center line of the limiting protrusion relative to the center line of the shell body is less than 1 mm.

9. The battery casing according to claim 1, characterized in that, The shell body has a third wall and a fourth wall that are disposed opposite to each other in the third direction. The first protrusion is disposed close to the third wall, and the second protrusion is disposed close to the fourth wall. The distance between the first protrusion and the third wall is 10mm-50mm, and the distance between the second protrusion and the fourth wall is 10mm-50mm.

10. The battery casing according to claim 1, characterized in that, In the third direction, the ratio of the sum of the widths of the first protrusion and the second protrusion to the width of the shell body in the third direction is 0.2-0.

5.

11. The battery casing according to claim 1, characterized in that, In the first direction, the ratio of the height of the limiting protrusion to the height of the shell body is 0.5-0.

9.

12. The battery casing according to claim 1, characterized in that, In the first direction, the limiting protrusion and the cover plate are spaced apart, with a minimum spacing of 5mm-20mm.

13. The battery casing according to claim 1, characterized in that, In the third direction, the difference between the width of the limiting protrusion and the width of the receiving groove is 0.1mm-0.2mm.

14. The battery casing according to claim 1, characterized in that, The area of ​​the first wall of the shell body is greater than the area of ​​the remaining surfaces adjacent to the first wall.

15. A single battery cell, characterized in that, It includes a battery cell and a battery housing as described in any one of claims 1-14, wherein the battery cell is disposed within a receiving cavity of the battery housing.

16. A battery pack, characterized in that, It includes at least two battery cells as described in claim 15, with two adjacent housing bodies having limiting protrusions that engage within receiving grooves of the adjacent housing bodies.

17. An electrical appliance, characterized in that, This includes the battery cell as described in claim 15 or the battery pack as described in claim 16.

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