Battery cell, battery pack, and electric device

Abstract

A battery cell, a battery pack, and an electric device. The battery cell comprises a casing (10) and an inner core (20); the casing (10) comprises a main body portion (11), and a first cover plate (12) and a second cover plate (13) connected to the main body portion (11); the main body portion (11), the first cover plate (12), and the second cover plate (13) define an accommodating cavity (14); the first cover plate (12) and the second cover plate (13) are arranged opposite to each other; the first cover plate (12) is provided with an explosion-proof valve (121); and the second cover plate (13) is provided with poles (131).

Description

Battery cells, battery packs and electrical equipment

[0001] This disclosure claims priority to Chinese Patent Application No. 202510129560.5, filed on February 5, 2025, entitled “Battery Cell, Battery Pack and Electrical Device”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This disclosure relates to a battery cell, a battery pack, and an electrical device. Background Technology

[0003] A battery explosion-proof valve is a safety device used to protect batteries. Its function is to release pressure when the internal pressure of the battery becomes too high, preventing the battery from exploding or leaking. However, in the event of thermal runaway, the battery core may block the valve opening, affecting the normal pressure release of the battery, leading to high internal pressure within the cell, and ultimately, the cell exploding and catching fire. Summary of the Invention

[0004] This disclosure provides a battery cell, a battery pack, and an electrical device. The following is an overview of the detailed description of this disclosure. This overview is not intended to limit the scope of the claims.

[0005] In a first aspect, a battery cell according to embodiments of this disclosure includes:

[0006] The housing includes a main body and a first cover plate and a second cover plate connected to the main body. The main body, the first cover plate and the second cover plate enclose a receiving cavity. The first cover plate and the second cover plate are disposed opposite to each other. The first cover plate is provided with an explosion-proof valve and the second cover plate is provided with a pole post.

[0007] An inner core is disposed within the receiving cavity and is spaced apart from the first cover plate along the thickness direction of the first cover plate;

[0008] The battery cell satisfies:

[0009] When B / A ≤ 0.6, H1 / A ≥ 0.4%; or,

[0010] When B / A > 0.6, H1 / A ≥ 0.26%;

[0011] Wherein, H1 is the distance from the inner core to the first cover plate along the thickness direction, A is the dimension of the shell along the thickness direction of the first cover plate, and B is the dimension of the shell along the length direction of the first cover plate.

[0012] In some embodiments, the battery cell satisfies:

[0013] H1 / A ≤ 1.67%.

[0014] In some embodiments, the battery cell satisfies:

[0015] When B / A ≤ 0.6, 0.6% ≤ H1 / A ≤ 1.67%;

[0016] When B / A > 0.6, 0.84% ​​≤ H1 / A ≤ 1.67%.

[0017] In some embodiments, the battery cell satisfies: B / A ≤ 0.6, and 2mm < H1 ≤ 8.4mm.

[0018] In some embodiments, the battery cell satisfies: B / A > 0.6, and 0.3mm ≤ H1 ≤ 1.5mm.

[0019] In some embodiments, the battery cell includes:

[0020] A support member is disposed within the receiving cavity and located between the inner core and the first cover plate to space the inner core and the first cover plate apart;

[0021] The support member has a first through hole communicating with the receiving cavity, and the first through hole is correspondingly provided with the explosion-proof valve.

[0022] In some embodiments, the support member includes:

[0023] The body, wherein the first through hole is disposed on the body;

[0024] A first protrusion is provided on the side of the body facing the inner core to separate the body and the inner core.

[0025] In some embodiments, the support member has a plurality of second through holes communicating with the receiving cavity, the plurality of second through holes being spaced apart, and the explosion-proof valve being offset from the plurality of second through holes along the thickness direction of the first cover plate.

[0026] In some embodiments, the support member includes:

[0027] The body, wherein the second through hole is disposed on the body;

[0028] The second protrusion is provided on the side of the body facing the first cover plate to separate the body and the first cover plate.

[0029] In some embodiments, the dimension of the support member along the thickness direction of the first cover plate is H2, satisfying: H2≤H1.

[0030] Secondly, embodiments of this disclosure also provide a battery pack, including the battery cells described in any one of the above-mentioned embodiments.

[0031] Thirdly, embodiments of this disclosure also provide an electrical device, including the battery pack described above, or including the battery cells described above.

[0032] This disclosure provides a battery cell including a casing and an inner core. The casing includes a main body and a first cover plate and a second cover plate connected to the main body. The main body, the first cover plate, and the second cover plate enclose a receiving cavity. The first cover plate and the second cover plate are disposed opposite to each other. The first cover plate is provided with an explosion-proof valve, and the second cover plate is provided with an electrode post. The inner core is disposed in the receiving cavity and is spaced apart from the first cover plate along the thickness direction of the first cover plate. The battery cell satisfies the following: when B / A≤0.6, H1 / A≥0.4%; or when B / A>0.6, H1 / A≥0.26%; where H1 is the distance from the inner core to the first cover plate along the thickness direction, A is the dimension of the casing along the thickness direction of the first cover plate, and B is the dimension of the casing along the length direction of the first cover plate. By placing the battery terminals and the explosion-proof valve on the opposite first and second cover plates, thermoelectric separation can be achieved. In the event of thermal runaway of the battery, when the ratio of the distance from the inner core to the first cover plate along the thickness direction to the outer shell along the thickness direction of the first cover plate is within the above range, the risk of the inner core blocking the valve port can be reduced, thereby enabling the battery to release pressure normally and improving battery safety.

[0033] After reading and understanding the accompanying diagrams and detailed descriptions, the other aspects can be understood. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 is a schematic diagram of the exploded structure of a single battery cell provided in an embodiment of this disclosure;

[0036] Figure 2 is a front view of a battery cell provided in an embodiment of this disclosure;

[0037] Figure 3 is a side view of a battery cell provided in an embodiment of this disclosure;

[0038] Figure 4 is a cross-sectional view along the MM direction in Figure 3 provided in an embodiment of this disclosure;

[0039] Figure 5 is a partial enlarged view of region C in Figure 4 provided in an embodiment of this disclosure;

[0040] Figure 6 is a front view of the support member provided in an embodiment of this disclosure;

[0041] Figure 7 is a perspective view of the support member provided in an embodiment of this disclosure.

[0042] Explanation of reference numerals in the attached figures:

[0043] 10-Shell; 11-Main body; 12-First cover plate; 121-Explosion-proof valve; 13-Second cover plate; 131-Pole post; 14-Receiving cavity; 20-Inner core; 30-Supporting member; 31-First through hole; 32-Second through hole; X-Thickness direction; Y-Length direction. Embodiments of the present invention

[0044] The technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without creative effort are within the scope of protection of this disclosure.

[0045] In the description of this disclosure, 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 one or more features. In the description of this disclosure, "multiple" means two or more, and "at least one" can mean one, two, or more, unless otherwise expressly specified.

[0046] With increasing demands for battery safety, thermoelectric separation has become an important battery design method. This means that the battery's electrode output terminals (terminals) and explosion-proof valves are located on different sides of the battery casing. The explosion-proof valve is generally located at the bottom of the casing. When thermal runaway occurs at a location far from the explosion-proof valve, the gas generated inside the battery will push the inner core towards the explosion-proof valve, causing the inner core to block the explosion-proof valve. This prevents the explosion-proof valve from releasing pressure normally, and as the gas pressure inside the battery continues to increase, it may even lead to the battery exploding and catching fire.

[0047] In view of the above, this disclosure provides a battery cell to overcome at least one of the above-mentioned technical problems.

[0048] Please refer to Figures 1, 2, 3, 4, and 5. In this embodiment of the present disclosure, the battery cell includes a housing 10 and an inner core 20. The housing 10 includes a main body 11 and a first cover plate 12 and a second cover plate 13 connected to the main body 11. The main body 11, the first cover plate 12, and the second cover plate 13 enclose a receiving cavity 14. The first cover plate 12 and the second cover plate 13 are disposed opposite to each other. The first cover plate 12 is provided with an explosion-proof valve 121, and the second cover plate 13 is provided with an electrode post 131. The inner core 20 is disposed within the receiving cavity 14 and is spaced apart from the first cover plate 12 along the thickness direction X.

[0049] In other words, the battery casing 10 may include a main body 11, a first cover plate 12, and a second cover plate 13. These three components can enclose a cavity 14 for accommodating the inner core 20 and other structures. The cavity 14 provides a favorable operating environment for the inner core 20 and other internal battery structures, reducing the impact of external environmental factors on these structures during operation. The first cover plate 12 and the second cover plate 13 are spaced apart along the thickness direction X, respectively located at both ends of the main body 11 along the thickness direction X. This allows the explosion-proof valve 121 on the first cover plate 12 and the terminal post 131 on the second cover plate 13 to be separated, preventing them from being located on the same side of the battery, thus achieving thermal-electric separation of the battery. In the event of thermal runaway, the high-temperature gas generated inside the battery can be discharged through the valve opening of the explosion-proof valve 121. Simultaneously, the inner core 20 is spaced apart from the first cover plate 12, preventing the inner core 20 from blocking the valve opening of the explosion-proof valve 121 on the first cover plate 12, and thus ensuring the discharge of high-temperature gas from inside the battery through the valve opening of the explosion-proof valve 121. The explosion-proof valve 121 is located on the side of the battery opposite to the terminal 131. Because the explosion-proof valve 121 is far from the terminal 131, the high-temperature gas generated inside the battery flows away from the terminal 131, thus not affecting the terminal 131 and its conductivity. This structure, which places the explosion-proof valve 121 and the terminal 131 on opposite sides of the battery, achieves thermoelectric separation, improving battery safety during use.

[0050] The battery cell satisfies the following conditions: when B / A ≤ 0.6, H1 / A ≥ 0.4%; or when B / A > 0.6, H1 / A ≥ 0.26%. As shown in Figure 4, H1 refers to the minimum distance along the thickness direction X between the surface of the inner core 20 facing the first cover plate 12 and the surface of the first cover plate 12 facing the inner core 20. As shown in Figure 2, A refers to the minimum distance along the thickness direction X between the top and bottom surfaces of the casing 10. As shown in Figure 2, B refers to the minimum distance along the length direction Y between the left and right sides of the casing 10. The thickness direction X is the direction of the thickness of the first cover plate 12, and the length direction Y is the direction of the length of the first cover plate 12.

[0051] When the ratio of dimension B of the housing 10 along the length Y direction of the first cover plate 12 to dimension A of the housing 10 along the thickness X direction of the first cover plate 12 is greater than 0.6, this type of battery is mostly used in automotive applications. When the ratio of dimension B of the housing 10 along the length Y direction of the first cover plate 12 to dimension A of the housing 10 along the thickness X direction of the first cover plate 12 is less than or equal to 0.6, this type of battery is mostly used in energy storage devices, portable electronic devices, drones and robots, portable lighting devices, and other similar devices. H1 and A can be measured using calipers or a 3D scanner. The structural performance of the explosion-proof valve 121 and the inner core 20 in this embodiment can be represented by whether the battery explodes. In specific testing, the inner core 20 was set at different positions so that the distance from the inner core 20 to the explosion-proof valve 121 was different, simulating the thermal runaway state of the battery. The opening status of the explosion-proof valve 121 and the state of the battery were observed. The test results of the embodiment and the comparative example are shown in Table 1 and Table 2 below (Table 1 is: the relationship between H1 / A and whether the battery explodes when B / A≤0.6; Table 2 is: the relationship between H1 / A and whether the battery explodes when B / A>0.6).

[0052] Table 1

[0053]

[0054]

[0055] Table 2

[0056]

[0057]

[0058] Based on Table 1 above and multiple embodiments, it can be seen that when B / A ≤ 0.6, H1 / A is greater than or equal to 0.4%. When the battery experiences thermal runaway, the explosion-proof valve 121 on the battery can open normally to relieve pressure, and the battery does not explode. Therefore, when H1 / A is within this range, the structural performance of the battery's explosion-proof valve 121 and inner core 20 is good. Under thermal runaway conditions, the valve of the explosion-proof valve 121 opens normally, and the inner core 20 will not block the valve of the explosion-proof valve 121. Even if the inner core 20 moves towards the explosion-proof valve 121 under the push of the gas generated by thermal runaway, the movement is very small, less than the distance H1 from the inner core 20 along the thickness direction X of the first cover plate 12 to the first cover plate 12. Therefore, the inner core 20 will not contact the first cover plate 12 equipped with the explosion-proof valve 121, and will not block the explosion-proof valve 121, allowing the explosion-proof valve 121 to open normally for pressure relief, thus improving battery safety. As can be seen from multiple comparative examples, when H1 / A is less than 0.4%, the value of H1 is relatively small. When the battery experiences thermal runaway, even if the inner core 20 moves slightly under the push of the gas, it may cause the inner core 20 to come into contact with the first cover plate 12, thereby blocking the explosion-proof valve 121 on the first cover plate 12. This prevents the gas inside the battery from being discharged through the explosion-proof valve 121, causing the explosion-proof valve 121 to fail to open normally and thus fail to depressurize the inside of the battery.

[0059] Based on Table 2 above and multiple embodiments, it can be seen that when B / A > 0.6, H1 / A is greater than or equal to 0.26%. When the battery experiences thermal runaway, the explosion-proof valve 121 on the battery can open normally to release pressure, reducing the risk of explosion due to excessive internal pressure. Therefore, when H1 / A is within this range, the structural performance of the battery's explosion-proof valve 121 and inner core 20 is good. Under thermal runaway conditions, the valve of the explosion-proof valve 121 opens normally, and the battery's inner core 20 will not block the valve of the explosion-proof valve 121. Even if the inner core 20 moves towards the explosion-proof valve 121 under the push of the gas generated by thermal runaway, the movement is very small, less than the distance H1 from the inner core 20 to the first cover plate 12 along the thickness direction X. Therefore, the inner core 20 will not come into contact with the first cover plate 12 equipped with the explosion-proof valve 121, and will not block the explosion-proof valve 121. This allows the explosion-proof valve 121 to open normally, relieve pressure, and improve battery safety. However, as shown in several comparative examples, when H1 / A is less than 0.26%, the value of H1 is small. Even if the inner core 20 moves only slightly under the push of the gas generated by thermal runaway during battery thermal runaway, it may still come into contact with the first cover plate 12, blocking the explosion-proof valve 121 on the first cover plate 12. This prevents the gas inside the battery from escaping through the explosion-proof valve 121, causing it to fail to open normally and relieve pressure inside the battery, potentially leading to an explosion.

[0060] Please refer to Figures 1, 2, 3, 4, and 5. As one embodiment of this disclosure, the battery cell satisfies: H1 / A ≤ 1.67%. When H1 / A is less than or equal to 1.67%, the battery can have a higher capacity (battery capacity refers to the amount of electrical energy a battery can store and release, usually measured in ampere-hours. Battery capacity represents the relationship between the current a battery can provide under specific conditions and its usage time), increasing the battery's discharge time and better meeting the requirements of battery setup and use. H1 and A can be measured using calipers or a 3D scanner. Generally, battery capacity is measured using the constant current discharge method. First, a constant current discharge device, voltmeter, ammeter, and a suitable load resistor need to be prepared. The battery, constant current discharge device, and load resistor are connected in series. Simultaneously, the voltage across the battery and the discharge current are measured using the voltmeter and ammeter, respectively. Next, a suitable constant current discharge current is set according to the battery specifications at a certain ratio (e.g., 0.2C, where C is the rated capacity). Then, the device is started to discharge, and the voltage and current changes are closely recorded during this period. Discharge stops when the battery voltage drops to the specified termination voltage. Finally, the battery capacity is calculated using the formula "Battery capacity (mAh) = Discharge current (mA) × Discharge time (h)". The test results of the example are shown in Tables 3 and 4 below (Table 3 is the relationship between H1 / A and battery capacity when B / A ≤ 0.6, where 0.4% ≤ H1 / A ≤ 1.67%; Table 4 is the relationship between H1 / A and battery capacity when B / A > 0.6, where 0.26% ≤ H1 / A ≤ 1.67%).

[0061] Table 3

[0062]

[0063] Table 4

[0064]

[0065] Combining Tables 3 and 4, it can be seen that for multiple batteries with the same dimensions in the length direction (Y) and thickness direction (X), when B / A ≤ 0.6, H1 / A ≤ 1.67%. When H1 / A is greater than 1.67%, the value of H1 is relatively large. During battery setup, if the distance between the inner core 20 and the first cover plate 12 is too large, although it will not cause the inner core 20 to block the explosion-proof valve 121, it will affect the volume of the inner core 20, resulting in a smaller inner core 20 volume and lower battery energy density. This setup method is not recommended. Therefore, under the condition that the battery will not explode, the value of H1 / A should be less than or equal to 1.67%, the inner core 20 can be set to a larger volume, the capacity variation of the inner core 20 is small, and with the values ​​of B and A remaining constant, a high capacity is maintained, resulting in a high battery energy density.

[0066] Similarly, for multiple batteries with the same dimensions in the length direction Y and thickness direction X, when B / A > 0.6, H1 / A ≤ 1.67%. When H1 / A is greater than 1.67%, the value of H1 is relatively large. During battery setup, if the distance between the inner core 20 and the first cover plate 12 is too large, although it will not cause the inner core 20 to block the explosion-proof valve 121, it will affect the volume of the inner core 20, resulting in a smaller inner core 20 volume and lower battery energy density. This setup method is not recommended. Therefore, under the condition that the battery will not explode, the value of H1 / A should be less than or equal to 1.67%, the inner core 20 can be set to a larger volume, the capacity variation of the inner core 20 is small, and with the values ​​of B and A remaining constant, a high capacity is maintained, resulting in a high energy density for the battery.

[0067] Please refer to Figures 1, 2, 3, 4 and 5. As an embodiment of this disclosure, the battery cell satisfies the following conditions: when B / A ≤ 0.6, 0.6 ≤ H1 / A ≤ 1.67%; or, when B / A > 0.6, 0.84 ≤ H1 / A ≤ 1.67%.

[0068] When B / A ≤ 0.6, 0.6% ≤ H1 / A ≤ 1.67%. In the event of thermal runaway (while the battery still has a large capacity), the explosion-proof valve 121 provides good venting when opened. H1 / A is generally within the range of 0.6% to 1.67%, and can be any value from 0.6%, 0.8%, 1.0%, 1.2%, 1.4%, 1.6%, to 1.67%, or any range between any two values. When B / A > 0.6, 0.84% ​​≤ H1 / A ≤ 1.67%. In the event of thermal runaway, the explosion-proof valve 121 also provides good venting. H1 / A is generally within the range of 0.84% ​​to 1.67%, and can be any value from 0.84%, 1.0%, 1.2%, 1.4%, 1.6%, to 1.67%, or any range between any two values. H1 and A can be measured using calipers or a 3D scanner. The venting effect of the battery can be represented by the relationship between the gas production V0 per unit time during thermal runaway of the inner core 20 and the gas discharge V1 per unit time of the explosion-proof valve 121. The gas production can be indirectly estimated by measuring parameters such as pressure and temperature changes during the battery's thermal runaway process, combined with information such as the battery volume and the gas law. For example, by using a pressure sensor to monitor the internal pressure changes of the battery in real time, and a temperature sensor to measure the temperature, the gas production V0 can be estimated based on the ideal gas law pV = nRT (where p is the gas pressure, V is the gas volume, n is the amount of gas, R is the gas constant, and T is the temperature), given the internal volume of the battery. For the measurement of V1, a suitable flow sensor, such as a thermal mass flow sensor or a vortex flow sensor, can be installed at the exhaust port of the explosion-proof valve 121. These sensors can measure the gas flow rate in real time, and the discharged gas volume V1 can be obtained by integrating the flow rate over time. A flow sensor capable of withstanding high temperatures, high pressures, and complex gas environments can be selected, ensuring that the installation location does not affect the normal operation of the explosion-proof valve 121. When testing the venting effect under battery thermal runaway conditions, it can be specified that a V1 / V0 value greater than or equal to 85% indicates good venting performance (with the opening size of the explosion-proof valve 121 remaining fixed). The test results of the embodiment are shown in Tables 5 and 6 below (Table 5: Relationship between H1 / A and V1 / V0 when B / A ≤ 0.6; Table 6: Relationship between H1 / A and V1 / V0 when B / A > 0.6).

[0069] Table 5

[0070]

[0071]

[0072] Table 6

[0073]

[0074] As shown in Table 5, when B / A ≤ 0.6, H1 / A is in the range of 0.6% to 1.67%, and the values ​​of V1 / V0 are all above 85%. Under the premise that the battery will not explode and has a high capacity, this battery can meet the venting requirements. The explosion-proof valve 121 on it has a good venting effect when opened, which can further reduce the risk of battery explosion. As shown in Table 6, when B / A > 0.6, H1 / A is in the range of 0.84% ​​to 1.67%, and the values ​​of V1 / V0 are also all above 85%. Under the premise that the battery will not explode and has a high capacity, this battery can meet the venting requirements. The explosion-proof valve 121 on it has a good venting effect when opened, which can further reduce the risk of battery explosion and improve safety.

[0075] Please refer to Figures 1, 2, 4, and 5. As an embodiment of this disclosure, the battery cell satisfies: B / A ≤ 0.6, and 2mm < H1 ≤ 8.4mm. Referring to Tables 1 and 2, for batteries in energy storage devices, portable electronic devices, drones and robots, portable lighting devices, etc., when the ratio of the dimension B of the casing 10 along the length direction Y to the dimension A of the casing 10 along the thickness direction X of the first cover plate 12 is less than or equal to 0.6, and H1 is within the range of 2mm to 8.4mm, in the event of thermal runaway, the inner core 20 will not block the valve port of the explosion-proof valve 121 on the battery, allowing the explosion-proof valve 121 to smoothly depressurize the battery. Furthermore, within this range, the battery has a large capacity.

[0076] Please refer to Figures 1, 2, 4, and 5. As an embodiment of this disclosure, the battery cell satisfies: B / A > 0.6, and 0.3mm ≤ H1 ≤ 1.5mm. Referring to Tables 1 and 2, for batteries used in vehicles, when the ratio of the dimension B along the length Y direction of the casing 10 to the dimension A along the thickness X direction of the casing 10 is greater than 0.6, and H1 is within the range of 0.3mm to 1.5mm, in the event of thermal runaway, the inner core 20 will not block the explosion-proof valve 121 on the battery, allowing the explosion-proof valve 121 to smoothly depressurize the battery. Furthermore, within this range, the battery has a larger capacity.

[0077] Please refer to Figures 1, 4, 6, and 7. In one embodiment of this disclosure, the battery cell includes a support member 30. The support member 30 is disposed within the receiving cavity 14 and located between the inner core 20 and the first cover plate 12, thus separating the inner core 20 and the first cover plate 12. The support member 30 has a first through hole 31 communicating with the receiving cavity 14, and the first through hole 31 is correspondingly disposed with the explosion-proof valve 121. That is, the support member 30 can be disposed between the inner core 20 and the first cover plate 12, and the support member 30 can be connected to the housing 10, for example, it can be connected to the main body 11. The support member 30 can provide a certain degree of support for the inner core 20. In the event of thermal runaway of the battery, the gas generated by the battery will push the inner core 20. If the inner core 20 moves towards the explosion-proof valve 121 under the push of the gas, the support member 30 can block the inner core 20, reducing the risk of the inner core 20 contacting the first cover plate 12 and causing blockage of the explosion-proof valve 121 on the first cover plate 12. The support member 30 is provided with a first through hole 31 connecting the receiving cavity 14 and the explosion-proof valve 121. Gas in the receiving cavity 14 can flow through the first through hole 31 to the explosion-proof valve 121, impacting the explosion-proof valve 121 and causing it to open normally. With the inner core 20 spaced apart from the first cover plate 12, the inner core 20 will not block the explosion-proof valve 121, while allowing the battery to depressurize normally, improving battery safety. The support member 30 can be made of high-temperature resistant materials such as alumina fiber or polyimide. A first protrusion facing the inner core 20 can be provided on the support member 30. When the battery experiences thermal runaway, the inner core 20 moves towards the support member 30 under the push of gas and comes into contact with the first protrusion. Due to the support of the first protrusion, and the fact that the first through hole 31 is located on the body of the support member 30, the risk of the inner core 20 blocking the first through hole 31 on the support member 30 is reduced, allowing gas generated by the battery to pass through the first through hole 31.

[0078] Please refer to Figures 1, 4, 6, and 7. As one embodiment of this disclosure, the support member 30 has a plurality of second through holes 32 communicating with the receiving cavity 14. The plurality of second through holes 32 are spaced apart. Along the thickness direction X of the first cover plate 12, the explosion-proof valve 121 is offset from the plurality of second through holes 32. That is, by providing a plurality of second through holes 32 on the support member 30, in the event of thermal runaway of the battery, the gas inside the receiving cavity 14 can flow through the plurality of second through holes 32 to the location of the explosion-proof valve 121. By providing multiple second through holes 32, the flow rate of the support member 30 can be increased, and its venting effect can be improved. This ensures that in the event of thermal runaway of the battery, sufficient gas can pass through the support member 30 to reach the explosion-proof valve 121 in a timely manner, compressing the valve and allowing it to open promptly. This relieves internal pressure in the battery and reduces the risk of insufficient gas pressure at the explosion-proof valve 121 due to obstruction by the support member 30, preventing the valve from opening in time. It also reduces the risk of poor venting efficiency after the valve opens due to obstruction by the support member 30. Because the second through holes 32 and the explosion-proof valve 121 are offset in the thickness direction X, a certain gap can be provided between the support member 30 and the first cover plate 12, allowing gas passing through the second through holes 32 to flow to the explosion-proof valve 121 and compress it. A second protrusion facing the first cover plate 12 can be provided on the support member 30. The second protrusion can contact the first cover plate 12. When the battery experiences thermal runaway, the gas generated by the inner core 20 or the battery may compress the support member 30. If the connection between the support member 30 and the main body 11 is not good, the support member 30 may move towards the first cover plate 12, causing the first cover plate 12 to block multiple second through holes 32. However, by providing the second protrusion between the main body of the support member 30 and the first cover plate 12, and by having a certain gap between the main body of the support member 30 and the first cover plate 12, and by providing multiple second through holes 32 on the main body of the support member 30, the multiple second through holes 32 can be prevented from being blocked by the first cover plate 12. Even if the support member 30 moves towards the first cover plate 12, the gas inside the battery can still flow through the multiple second through holes 32 to the position of the explosion-proof valve 121 and be discharged through the explosion-proof valve 121.

[0079] Please refer to Figures 1, 4, and 5. In one embodiment of this disclosure, the dimension of the support member 30 along the thickness direction X of the first cover plate 12 is H2, satisfying: H2 ≤ H1. That is, the dimension of the support member 30 along the thickness direction X of the first cover plate 12 can be less than or equal to the distance from the inner core 20 along the thickness direction X to the first cover plate 12. By providing the support member 30, the risk of clogging the explosion-proof valve 121 due to the small distance from the inner core 20 along the thickness direction X to the first cover plate 12 can be reduced in the event of thermal runaway of the battery. When H2 = H1, the two sides of the support member 30 along the thickness direction X are in contact with the inner core 20 and the first cover plate 12, respectively. In the event of thermal runaway, due to the obstruction of the support member 30, the inner core 20 will not move towards the explosion-proof valve 121, allowing gas to be smoothly discharged through the explosion-proof valve 121. When H2 < H1, in the event of thermal runaway, the inner core 20 may move towards the explosion-proof valve 121 under the push of the gas. However, after moving a certain distance, it will come into contact with the support 30 and be blocked by the support 30, thus preventing it from moving further and blocking the explosion-proof valve 121. This also allows the gas to be discharged smoothly through the explosion-proof valve 121.

[0080] This disclosure also provides a battery pack for storing and releasing electrical energy, including a housing and multiple battery cells as described above, the battery cells being housed within the housing. When multiple battery cells are stacked to form a battery pack, the explosion-proof valves 121 on different battery packs are arranged opposite each other, ensuring that when the explosion-proof valve 121 is activated, the ejected material will not affect the terminals 131 on other battery packs, thus reducing the risk of short-circuit failure in other battery packs. The explosion-proof valves 121 on corresponding battery packs can be staggered, thereby reducing the impact of the opening of the explosion-proof valve 121 on the opposing explosion-proof valves 121. The battery pack can be a charging and discharging structure composed of multiple battery cells, such as a battery module, battery pack, battery cluster, battery stack, battery tower, or battery array. Battery cells include, but are not limited to, lithium-ion secondary batteries, lithium-ion primary batteries, lithium-sulfur batteries, sodium-lithium-ion batteries, sodium-ion batteries, or magnesium-ion batteries, etc., and this disclosure does not limit the types of cells.

[0081] This disclosure also provides an electrical device, including the battery pack described above, or including individual battery cells described above. The battery pack or individual battery cells are the power source for the electrical device. The electrical device can be a mobile phone, portable device, laptop computer, electric vehicle, electric car, ship, spacecraft, electric toy, or power tool, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft; electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys; power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc.

[0082] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0083] The battery cell, battery pack, and electrical equipment provided in the embodiments of this disclosure have been described in detail above, and specific examples have been used to illustrate the principles and implementation methods of this disclosure. The descriptions of the embodiments above are only for the purpose of helping to understand the technical solutions and core ideas of this disclosure. Those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A single battery cell, comprising: The housing (10) includes a main body (11), and a first cover plate (12) and a second cover plate (13) connected to the main body (11). The main body (11), the first cover plate (12) and the second cover plate (13) enclose a receiving cavity (14). The first cover plate (12) and the second cover plate (13) are arranged opposite to each other. The first cover plate (12) is provided with an explosion-proof valve (121), and the second cover plate (13) is provided with a pole post (131). The inner core (20) is disposed in the receiving cavity (14) and is spaced apart from the first cover plate (12) along the thickness direction (X) of the first cover plate (12); The battery cell satisfies: When B / A ≤ 0.6, H1 / A ≥ 0.4%; or, When B / A > 0.6, H1 / A ≥ 0.26%; Wherein, H1 is the distance from the inner core (20) to the first cover plate (12) along the thickness direction (X), A is the dimension of the shell (10) along the thickness direction (X) of the first cover plate (12), and B is the dimension of the shell (10) along the length direction (Y) of the first cover plate (12).

2. The battery cell according to claim 1, wherein, The battery cell also satisfies: H1 / A ≤ 1.67%.

3. The battery cell according to claim 2, wherein, The battery cell also satisfies: When B / A ≤ 0.6, 0.6% ≤ H1 / A ≤ 1.67%.

4. The battery cell according to claim 2, wherein, The battery cell also satisfies: When B / A > 0.6, 0.84% ​​≤ H1 / A ≤ 1.67%.

5. The battery cell according to claim 1, wherein, The battery cell also satisfies the following conditions: B / A≤0.6, and 2mm<H1≤8.4mm.

6. The battery cell according to claim 1, wherein, The battery cell also satisfies the following conditions: B / A > 0.6, and 0.3mm ≤ H1 ≤ 1.5mm.

7. The battery cell according to claim 1, wherein, The battery cell also includes: A support member (30) is disposed within the receiving cavity (14) and located between the inner core (20) and the first cover plate (12) to space the inner core (20) and the first cover plate (12). The support member (30) has a first through hole (31) communicating with the receiving cavity (14), and the first through hole (31) is correspondingly provided with the explosion-proof valve (121).

8. The battery cell according to claim 7, wherein, The support member (30) has a plurality of second through holes (32) communicating with the receiving cavity (14). The plurality of second through holes (32) are spaced apart along the thickness direction (X) of the first cover plate (12). The explosion-proof valve (121) is offset from the plurality of second through holes (32).

9. The battery cell according to claim 7, wherein, The dimension of the support member (30) along the thickness direction (X) of the first cover plate (12) is H2, which satisfies: H2≤H1.

10. A battery pack comprising a battery cell as described in any one of claims 1 to 9.

11. An electrical device comprising a battery cell as described in any one of claims 1 to 9, or comprising a battery pack as described in claim 10.

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