Cover plate assembly of battery cell, and battery casing, battery cell, battery pack and electric device

Abstract

Disclosed in the present application are a cover plate assembly of a battery cell, and a battery casing, a battery cell, a battery pack and an electric device. The cover plate assembly of the battery cell comprises a cover plate and a cap, wherein the cover plate is adapted to connect to a casing of the battery cell, the cover plate is provided with a communication port running therethrough, the communication port is adapted to be in communication with a first accommodating cavity of the casing, the cap is provided on the cover plate and directly faces the communication port, the cap is fixedly connected to the cover plate, at least part of the cap protrudes in a direction away from the communication port so as to form a protrusion, a second accommodating cavity in communication with the communication port is formed on the side of the protrusion facing the communication port, the second accommodating cavity is configured to temporarily store gas, at least one rupture disc is provided on the protrusion, and the rupture disc is configured to break once the internal pressure of an electrode cell reaches a set pressure, thereby connecting to the second accommodating cavity. In this way, the use safety of the battery cell can be ensured to a certain extent, and the volumetric energy density of the battery cell can also be improved, so as to ensure the working performance of the battery cell.

Description

Battery cell cover plate assembly, battery shell, battery cell, battery pack and electric device

[0001] The present application claims priority to the Chinese patent application No. 202421805458.X, filed on July 26, 2024, and entitled "Battery cell cover plate assembly, battery shell, battery cell, battery pack and electric device", the content of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present disclosure relates to the technical field of battery, and in particular, to a battery cell cover plate assembly, a battery shell, a battery cell, a battery pack and an electric device. BACKGROUND

[0003] Batteries are widely concerned due to their high energy density and environmental friendliness, and are widely used in large devices such as energy storage devices and electric vehicles. However, the safety of the battery is the most important factor affecting its development. For example, when the water content in the battery cell exceeds the standard, the SEI film (Solid Electrolyte Interface membrane) is unstable, the battery is overcharged or overdischarged, or the battery is misused such as short circuit or extrusion, it will cause the battery to produce gas, catch fire, and even explode. The common method to solve these problems is to add a pressure relief valve on the top cover of the battery. When the battery has the above-mentioned conditions, gas is generated inside the battery. When the internal gas pressure of the battery reaches the burst pressure of the pressure relief valve, the pressure relief valve on the top cover breaks, thereby allowing the internal gas of the battery to be discharged from the pressure relief valve, preventing the battery from exploding due to gas expansion.

[0004] However, due to the improvement of the volume utilization rate of the existing battery shell, the pressure relief valve is close to the pole core, which causes the gas generated inside the battery to be unable to be stored, and the pole core is easily expanded seriously, affecting the safety of the battery in use. SUMMARY

[0005] The present disclosure aims to at least solve one of the technical problems existing in the prior art. To this end, the first purpose of the present disclosure is to provide a battery cell cover plate assembly, which can ensure the safety of the battery cell to a certain extent while achieving high volume energy density of the battery cell, and solve the technical problems of low volume energy density and poor safety of the battery cell in the prior art.

[0006] The second purpose of the present disclosure is to provide a battery shell with the above-mentioned cover plate assembly.

[0007] The third purpose of the present disclosure is to provide a battery cell with the above-mentioned cover plate assembly or battery shell.

[0008] A fourth object of the present disclosure is to provide a battery pack having the battery cell.

[0009] A fifth object of the present disclosure is to provide an electrical device having the battery pack.

[0010] The cover plate assembly of the battery cell according to the embodiments of the present disclosure comprises: a cover plate body adapted to connect a shell of the battery cell, the cover plate body being provided with a communication port penetrating therethrough, the communication port being adapted to communicate a first accommodating cavity of the shell, the first accommodating cavity being adapted to place a pole core; a cover cap provided on the cover plate body and opposite to the communication port, the cover cap being fixedly connected with the cover plate body, at least part of the cover cap being protruded away from the communication port to form a protruding portion, a side of the protruding portion facing the communication port forming a second accommodating cavity communicating with the communication port, the second accommodating cavity being used for buffering gas, at least one explosion-proof valve being provided on the protruding portion, the explosion-proof valve being configured to break to communicate the second accommodating cavity when a set pressure is reached inside the pole core.

[0011] The cover plate assembly of the battery cell according to the embodiments of the present disclosure, by providing the fixedly connected cover plate body and cover cap, the cover plate body and cover cap cooperate to form the protruding portion with a certain protruding height on the cover plate assembly, so as to reduce the forming difficulty of the protruding portion and facilitate to ensure the protruding height of the protruding portion, so as to facilitate to place at least part of the tab of the battery cell inside the cover plate assembly, so as to avoid the tab occupying too much space in the shell of the battery cell to some extent, improve the space utilization of the shell, facilitate to ensure the volumetric energy density of the battery cell, at the same time, by forming the second accommodating cavity communicating with the communication port on the side of the protruding portion facing the communication port, and buffering the gas by using the second accommodating cavity, and providing at least one explosion-proof valve on the protruding portion, it is convenient to discharge the high-temperature and high-pressure gas generated when the battery cell is in thermal runaway, so as to avoid the pole core of the battery cell from expanding too much to some extent, so as to ensure the use safety of the battery cell to some extent, and prolong the cycle life of the battery cell. That is, the cover plate assembly of the present disclosure can not only improve the volumetric energy density of the battery cell, but also ensure the use safety of the battery cell to some extent and prolong the cycle life of the battery cell.

[0012] In some embodiments, the second accommodating cavity is used to accommodate at least part of the tab of the battery cell.

[0013] In some embodiments, a plurality of explosion-proof valves are provided on the protruding portion.

[0014] In some embodiments, at least one explosion-proof valve is provided on the wall surface of the protruding portion opposite to the communication port.

[0015] In some embodiments, at least one sidewall of the protruding portion is provided with a mounting opening penetrating therethrough, and an anti-explosion sheet is mounted in the mounting opening, and the anti-explosion sheet forms the anti-explosion valve.

[0016] In some embodiments, an area of the sidewall provided with the mounting opening is S1, and an area of the mounting opening is S2, and the S1 and the S2 satisfy: 0.05≤S2 / S1≤0.95.

[0017] In some embodiments, the anti-explosion sheet is provided with a first notch.

[0018] In some embodiments, the cover plate assembly further comprises a protection sheet, which is arranged in the mounting opening and located on a side of the anti-explosion sheet away from the second accommodating cavity.

[0019] In some embodiments, a thickness of the protection sheet ranges from 0.1mm to 1.5mm.

[0020] In some embodiments, at least one sidewall of the protruding portion is provided with a second notch, and the second notch forms the anti-explosion valve.

[0021] In some embodiments, the second notch comprises at least one arc-shaped notch and / or at least one straight line notch.

[0022] In some embodiments, a thickness of the sidewall provided with the second notch is greater than 0.2mm.

[0023] In some embodiments, an area of the sidewall provided with the second notch is S1, and a covered area of a projection of the second notch on a first plane is S3, and the S1 and the S3 satisfy: 0.05≤S3 / S1≤0.95, and the first plane is perpendicular to a thickness direction of the cover plate body.

[0024] In some embodiments, a thickness W of the cover cap ranges from 0.3mm to 5mm; and / or, a protruding height H1 of the protruding portion ranges from 2mm to 50mm.

[0025] In some embodiments, on a first plane, a projection area of the communication opening is S1, and a projection area of the cover plate body excluding the communication opening is S4, and the S1 and the S4 satisfy: 0.1≤S1 / S4≤3, and the first plane is perpendicular to a thickness direction of the cover plate body.

[0026] In some embodiments, the cover plate assembly further comprises a pole assembly, and the pole assembly is arranged in the cover plate body; a protruding height H1 of the protruding portion and a height H2 of the pole assembly protruding from the cover plate body satisfy: -5mm≤H1-H2≤5mm.

[0027] In some embodiments, the cover plate assembly further comprises a liquid injection hole, which is arranged on the cover plate body and / or the protruding portion, and which communicates with the first accommodating cavity.

[0028] In some embodiments, the first sidewall of the cover plate body is provided with a mounting groove in a protruding direction towards the protruding portion, and the cover cap is provided with a mounting flange which cooperates with the mounting groove and is limited in the mounting groove.

[0029] In some embodiments, the mounting groove is arranged around the outer periphery of the communication port and communicates with the communication port, and the shape of the mounting flange matches the shape of the mounting groove.

[0030] In some embodiments, the mounting groove extends in a direction away from the communication port, and the extension length of the mounting groove on the same side of the communication port ranges from 0.5mm to 3mm.

[0031] The battery shell according to the embodiments of the present disclosure comprises: a shell, a first accommodating cavity with an opening is formed in the shell, and a pole core is adapted to be placed in the first accommodating cavity; a cover plate assembly, which is the aforementioned cover plate assembly, is arranged at the opening.

[0032] The battery shell according to the embodiments of the present disclosure, by adopting the aforementioned cover plate assembly, when the battery shell is applied to a battery monomer, the high volumetric energy density of the battery monomer is realized, and the use safety of the battery monomer is ensured to a certain extent.

[0033] The battery monomer according to the embodiments of the present disclosure comprises a pole core and the aforementioned cover plate assembly or the aforementioned battery shell, and at least part of the tab of the pole core is arranged in the second accommodating cavity.

[0034] The battery monomer according to the embodiments of the present disclosure, by adopting the aforementioned cover plate assembly, realizes the high volumetric energy density of the battery monomer, and ensures the use safety of the battery monomer to a certain extent.

[0035] In some embodiments, the tab is arranged in a spaced manner with the cover cap, and the minimum distance between the tab and the cover cap ranges from 1mm to 50mm.

[0036] The battery pack according to the embodiments of the present disclosure comprises a plurality of the aforementioned battery monomers.

[0037] The battery pack according to the embodiments of the present disclosure, by adopting the aforementioned battery monomer, is conducive to improving the energy density of the battery pack and ensuring the use safety of the battery pack.

[0038] The electric device according to the embodiments of the present disclosure comprises the aforementioned battery pack.

[0039] The power utilization device according to the embodiments of the present disclosure has the advantages of improving the working performance of the power utilization device and ensuring the use safety of the power utilization device by using the battery pack.

[0040] Additional aspects and advantages of the present disclosure will become apparent from the following description, or will be learned by practice of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0041] The above and / or additional aspects and advantages of the present disclosure will become apparent and be readily appreciated from the following description, taken in conjunction with the accompanying drawings, in which:

[0042] FIG. 1 is an exploded view of a partial structure of a battery cell according to some embodiments of a first aspect of the present disclosure.

[0043] FIG. 2 is an enlarged view of region I in FIG. 1.

[0044] FIG. 3 is a cross-sectional view of a partial structure of a battery cell according to some embodiments of the first aspect of the present disclosure.

[0045] FIG. 4 is a schematic view of a cap according to some embodiments of a second aspect of the present disclosure.

[0046] FIG. 5 is a schematic view of a cap according to some embodiments of the first aspect of the present disclosure.

[0047] FIG. 6 is an exploded view of a partial structure of a battery cell according to some embodiments of a third aspect of the present disclosure.

[0048] FIG. 7 is a schematic view of a cap according to some embodiments of the third aspect of the present disclosure.

[0049] FIG. 8 is an exploded view of a partial structure of a battery cell according to some embodiments of a fourth aspect of the present disclosure.

[0050] FIG. 9 is a schematic view of a cap according to some embodiments of the fourth aspect of the present disclosure.

[0051] FIG. 10 is a schematic view of a cap according to some embodiments of a fifth aspect of the present disclosure.

[0052] FIG. 11 is a schematic view of a cap according to some embodiments of a sixth aspect of the present disclosure.

[0053] FIG. 12 is a schematic view of a cap according to some embodiments of a seventh aspect of the present disclosure.

[0054] FIG. 13 is a schematic view of a cap according to some embodiments of an eighth aspect of the present disclosure.

[0055] FIG. 14 is a cross-sectional view of a cap according to some embodiments of a ninth aspect of the present disclosure.

[0056] FIG. 15 is an exploded view of a partial structure of a battery cell according to some embodiments of a tenth aspect of the present disclosure.

[0057] FIG. 16 is a schematic view of the cap according to some embodiments of the tenth aspect of the present disclosure.

[0058] Reference signs: 1000, battery cell; 100, cover plate assembly; 110, cover plate body; 111, communication port; 112, first side wall; 1121, mounting groove; 120, cap; 121, protruding part; 1211, second accommodating cavity; 1212, mounting port; 1213, second score; 122, mounting flange; 130, explosion-proof valve; 131, explosion-proof sheet; 140, pole column assembly; 200, shell; 210, first accommodating cavity; 211, opening; 300, tab; 500, insulating piece; 600, battery case. DETAILED DESCRIPTION

[0059] The embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. The embodiments described below are exemplary and are intended to explain the present disclosure, and are not to be understood as limiting the present disclosure.

[0060] In the description of the present disclosure, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like are based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present disclosure and simplifying the description, and are not to be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present disclosure.

[0061] The cover plate assembly 100 of the battery cell 1000 according to the embodiments of the present disclosure is described below with reference to the accompanying drawings.

[0062] In combination with FIGS. 1, 2 and 3, the cover plate assembly 100 of the battery cell 1000 according to the embodiments of the present disclosure includes a cover plate body 110 and a cap 120.

[0063] As shown in Figures 1 and 3, the cover plate body 110 is adapted to connect to the outer shell 200 of the battery cell 1000. The cover plate body 110 has a through-hole 111, which is adapted to connect to the first receiving cavity 210 of the outer shell 200. The first receiving cavity 210 is adapted to place the electrode core. This means that the cover plate body 110 has a through-hole 111, which connects to the opposite sides of the cover plate body 110. Simultaneously, the battery cell 1000 has an outer shell 200, which has a first receiving cavity 210 for placing the electrode core. The cover plate body 110 is connected to the outer shell 200, and the through-hole 111 on the cover plate body connects to the first receiving cavity 210 of the outer shell 200, facilitating the formation of the battery cell 1000. Furthermore, the outer shell 200 can support the cover plate body 110, ensuring the positional stability of the cover plate body 110 and contributing to its operational performance.

[0064] In addition, the connecting port 111 is connected to the first receiving cavity 210 of the outer shell 200 so that the high temperature and high pressure gas generated by the electrode core in the first receiving cavity 210 during thermal runaway can be discharged through the connecting port 111, thereby improving the safety of the electrode core in use.

[0065] Referring to Figures 1, 2, and 3, a cap 120 is disposed on the cover plate body 110 and faces the communication port 111. The cap 120 is fixedly connected to the cover plate body 110. At least a portion of the cap 120 protrudes in a direction away from the communication port 111 to form a protrusion 121. The side of the protrusion 121 facing the communication port 111 forms a second receiving cavity 1211 that connects to the communication port 111. The second receiving cavity 1211 is used to buffer gas. At least one explosion-proof valve 130 is provided on the protrusion 121. The explosion-proof valve 130 is configured to break after a set pressure is reached inside the electrode core to connect to the second receiving cavity 1211.

[0066] This refers to the situation where, when the cap 120 is placed on the cover plate body 110, the second receiving cavity 1211 of the protrusion 121 on the cap 120 is connected to the connecting port 111. Since the connecting port 111 is connected to the first receiving cavity 210 of the outer shell 200, the first receiving cavity 210 and the second receiving cavity 1211 are connected. In this way, when the electrode core in the first receiving cavity 210 experiences thermal runaway, the generated high-temperature and high-pressure gas can be discharged into the second receiving cavity 1211 through the connecting port 111. This allows the second receiving cavity 1211 to buffer the gas, preventing excessive gas from being stored in the first receiving cavity 210, which could cause the battery cell 1000 to swell and squeeze adjacent battery cells 1000.

[0067] Meanwhile, at least one explosion-proof valve 130 is provided on the protrusion 121, and the explosion-proof valve 130 is configured to break after the set pressure is reached inside the electrode core to connect to the second receiving cavity 1211. This allows the explosion-proof valve 130 to be effectively opened to vent gas when the gas pressure inside the battery cell 1000 reaches the upper limit, which can effectively guide the gas out of the battery cell 1000. This means that the large amount of gas generated inside the battery cell 1000 is discharged more quickly, thereby eliminating the explosion hazard in time and improving the safety of the battery cell 1000.

[0068] In addition, placing the explosion-proof valve 130 on the protrusion 121 can also move the explosion-proof valve 130 away from the pole core, improve the opening function of the explosion-proof valve 130, and prevent the explosion-proof valve 130 from failing to a certain extent.

[0069] In other words, this disclosure places the explosion-proof valve 130 on the protrusion 121. On the one hand, this allows the explosion-proof valve 130 to be located away from the electrode core, reducing the difficulty of opening the explosion-proof valve 130 and thus ensuring the working performance of the explosion-proof valve 130. On the other hand, since the protrusion 121 forms a second receiving cavity 1211, when gas is generated inside the battery cell 1000, some of the gas can be stored in the second receiving cavity 1211, preventing the battery cell 1000 from bulging and squeezing adjacent battery cells 1000. Furthermore, the second receiving cavity 1211 can be used to store gas, making the gas concentrated. Thus, when the internal gas pressure reaches the upper limit, the explosion-proof valve 130 can be effectively opened to vent the gas, which can effectively guide the gas out of the battery cell 1000. This means that the large amount of gas generated inside the battery cell 1000 can be discharged more quickly, thereby eliminating the explosion hazard in a timely manner and improving the safety of the battery cell 1000.

[0070] In addition, by placing the explosion-proof valve 130 on the protrusion 121, the cap 120 can be used to support the explosion-proof valve 130, thereby improving the positional stability of the explosion-proof valve 130 and ensuring its working performance.

[0071] It is worth noting that the present disclosure configures the cover plate assembly 100 to include a cover plate body 110 and a cap 120, and fixes the cover plate body 110 and the cap 120 together so that the cover plate body 110 and the cap 120 form two separate structures. At the same time, the cover plate body 110 and the cap 120 cooperate to form a second receiving cavity 1211. Compared with directly stamping the cover plate body 110 to form the receiving cavity, this not only reduces the forming difficulty of the second receiving cavity 1211, but also ensures the space of the second receiving cavity 1211 in the height direction.

[0072] In other words, by providing a through-hole 111 on the cover body 110 and setting the cap 120 opposite to the through-hole 111, and forming a second receiving cavity 1211 in the protrusion 121 that connects to the through-hole 111, this disclosure can ensure that the second receiving cavity 1211 can effectively contain the buffer gas, thereby avoiding the expansion of the battery cell 1000 to a certain extent.

[0073] It should also be noted that the fixed connection between the cover plate body 110 and the cap 120 mentioned above can be welding, bonding or bolting.

[0074] In other words, this disclosure configures the cover plate assembly 100 to include a cover plate body 110 and a cap 120, with a communication port 111 on the cover plate body 110 and a second receiving cavity 1211 on the cap 120 that communicates with the communication port 111, thereby forming a cavity on the cover plate assembly 100 that communicates with the first receiving cavity 210 of the outer shell 200, so that the second receiving cavity 1211 can buffer the high-temperature and high-pressure gas generated by the electrode core when thermal runaway occurs.

[0075] In a specific example, the explosion-proof valve 130 is mainly used to rupture when a large amount of gas is generated inside the battery cell 1000, so that the gas inside the battery cell 1000 can be discharged. This avoids damage to electronic components caused by electrolyte, high-temperature substances and sparks ejected from inside the battery cell 1000 to a certain extent, thereby reducing the safety hazards of electronic components. In other words, it avoids safety problems caused by the inability of the battery cell 1000 to discharge internal pressure in a timely manner, and improves the safety of the battery cell 1000 in use.

[0076] In summary, the cover plate assembly 100 of the battery cell 100 disclosed herein can simultaneously ensure the high volumetric energy density and high safe pressure relief performance of the battery cell 1000.

[0077] It should also be noted that the above-mentioned provision of at least one explosion-proof valve 130 on the protrusion 121 means that one or more explosion-proof valves 130 may be provided on the protrusion 121. In the description of this disclosure, unless otherwise stated, "multiple" means two or more.

[0078] As can be seen from the above structure, the cover plate assembly 100 of the battery cell 1000 in this embodiment of the present disclosure has two relatively independent structures (cover plate body 110 and cap 120), and a communication port 111 is provided on the cover plate body 110 and a second receiving cavity 1211 communicating with the communication port 111 is provided on the cap 120, so as to form a cavity communicating with the tab 300 of the battery cell 100 on the cover plate assembly 100. This facilitates the buffering of high temperature and high pressure gas generated by the electrode core when thermal runaway occurs into the cover plate assembly 100, avoiding the phenomenon that excessive gas stored in the outer casing 200 causes the battery cell 1000 to bulge and squeeze the adjacent battery cells 1000.

[0079] Meanwhile, an explosion-proof valve 130 is provided and placed on the protrusion 121. This allows the explosion-proof valve 130 to be placed away from the electrode core, and also ensures that when the explosion-proof valve 130 is opened to vent, a large amount of gas generated inside the battery cell 1000 can be quickly discharged, thereby improving the safety of the battery cell 1000.

[0080] Understandably, compared to the prior art, this disclosure utilizes the cover plate body 110 and the cap 120 to form a second receiving cavity 1211 on the cover plate assembly 100 that connects to the electrode tab 300, and places the explosion-proof valve 130 on the protrusion 121 formed by the cap 120. While increasing the volumetric energy density of the battery cell 1000, it also enables the battery cell 1000 to safely release pressure, thereby improving the safety of the battery cell 1000 in use.

[0081] In the description of this disclosure, features marked with "first" or "second" may explicitly or implicitly include one or more of the same feature, used to distinguish and describe features, without any order or distinction of importance.

[0082] In some embodiments, the cap 120 is formed as a metal part. That is, the cap 120 is made of metal material to ensure the structural strength of the cap 120.

[0083] Optionally, the cover body 110 is formed as a metal part. This means that the cover body 110 can also be made of metal material to ensure the structural strength of the cover body 110, while also helping to reduce the difficulty of fixing the cover body 110 and the cap 120.

[0084] In a specific example, when both the cover body 110 and the cap 120 are made of metal, the cover body 110 and the cap 120 can be fixedly connected by welding to ensure the connection strength between the cover body 110 and the cap 120, thereby stabilizing the relative position of the cover body 110 and the cap 120, improving the structural stability of the cover assembly 100, and thus ensuring the working performance of the cover assembly 100.

[0085] It should be noted that the shape of the cap 120 shown in Figure 1 is similar to that of a rectangle. Of course, in some other embodiments, the shape of the cap 120 may also be similar to that of a circle (as shown in Figure 4), an ellipse, or a square.

[0086] Furthermore, the shape of the cover body 110 is not limited to a rectangle. The shape of the cover body 110 can be adapted to the overall shape of the battery cell 1000. This disclosure does not impose any specific limitations.

[0087] In some embodiments, as shown in Figures 1, 2, and 3, the second receiving cavity 1211 is used to receive at least a portion of the tab 300 of the battery cell 1000. This means that the battery cell 1000 includes the tab 300, and at least a portion of the tab 300 can be fitted into the second receiving cavity 1211 formed by the cap 120. This can, to some extent, prevent the tab 300 from occupying too much space within the housing 200, thereby improving the space utilization of the housing 200 and ensuring sufficient space within the housing 200 for setting the coating area of ​​the electrode core, thus facilitating an increase in the capacity density of the battery cell 1000.

[0088] In other words, to address the technical problem in the prior art where the tab 300 easily leads to wasted space under the cover plate, thereby reducing the space utilization rate inside the casing 200 and resulting in a decrease in the volumetric energy density of the battery cell 1000, this disclosure configures the cover plate assembly 100 of the battery cell 1000 to include a cover plate body 110 and a cap 120, and configures at least a portion of the cap 120 to protrude in a direction away from the connecting port 111 to form a second receiving cavity 1211 on the cap 120 that connects to the connecting port 111. During the subsequent assembly of the battery cell 1000, it is convenient to assemble at least a portion of the tab 300 into the protrusion 121 formed by the cap 120, that is, to realize the assembly of at least a portion of the tab 300 into the cover plate assembly 100. This can, to a certain extent, avoid the tab 300 occupying too much space inside the casing 200, thereby improving the space utilization rate of the casing 200, so that there is enough space inside the casing 200 to set the coating area of ​​the electrode core, which is conducive to improving the capacity density of the battery cell 1000.

[0089] In a specific example, during the assembly of the tab 300 and the cover assembly 100, at least a portion of the tab 300 passes through the communication port 111 on the cover body 110 and is assembled in the second receiving cavity 1211, so as to realize the second receiving cavity 1211 to accommodate at least a portion of the tab 300 of the battery cell 1000.

[0090] In some embodiments, as shown in FIG1, FIG2 and FIG3, in the protruding direction toward the protrusion 121, the first sidewall 112 of the cover body 110 is provided with a mounting groove 1121, and the cap 120 has a mounting flange 122 that cooperates with the mounting groove 1121, and the mounting flange 122 is limited within the mounting groove 1121. This refers to the fact that, in the protruding direction of the protrusion 121, the cover plate body 110 has a first side wall 112, the first side wall 112 is provided with a mounting groove 1121, and the cap 120 is provided with a mounting flange 122 that can be limited and fitted within the mounting groove 1121. In this way, during the process of fixing the cap 120 and the cover plate body 110, the mounting flange 122 can be limited within the mounting groove 1121, and the fixing connection between the cap 120 and the cover plate body 110 is achieved by using the mounting flange 122 and the mounting groove 1121 to reduce the difficulty of connecting the cap 120 and the cover plate body 110, and helps to ensure the connection quality between the cap 120 and the cover plate body 110.

[0091] The mounting flange 122 and the mounting groove 1121 can also perform initial positioning of the cap 120 during the connection process between the cap 120 and the cover plate body 110, so that the position of the cap 120 relative to the cover plate body 110 is stable, thereby further reducing the difficulty of connecting the cap 120 and the cover plate body 110.

[0092] In some embodiments, as shown in Figures 1, 2, and 3, the mounting groove 1121 surrounds the outer periphery of the communication port 111 and communicates with the communication port 111, and the shape of the mounting flange 122 matches the shape of the mounting groove 1121. By configuring the mounting groove 1121 to surround the outer periphery of the communication port 111 and communicate with it, when the mounting flange 122 and the mounting groove 1121 cooperate to achieve a fixed connection between the cap 120 and the cover plate body 110, it can be ensured that the second receiving cavity 1211 on the protrusion 121 can communicate with the communication port 111. This allows at least a portion of the tab 300 to pass through the communication port 111 on the cover plate body 110 and be fitted into the second receiving cavity 1211, facilitating the increase of the energy density of the battery cell 1000.

[0093] Meanwhile, by setting the shape of the mounting flange 122 to match the shape of the mounting groove 1121, the mounting flange 122 can be limited and fitted within the mounting groove 1121, which helps to ensure the contact area between the mounting flange 122 and the mounting groove 1121, thereby ensuring the connection strength between the mounting flange 122 and the mounting groove 1121, and thus ensuring the connection strength between the cap 120 and the cover plate body 110.

[0094] It should be noted that the shape of the mounting flange 122 matching the shape of the mounting groove 1121 means that the extension direction of the mounting flange 122 is consistent with the extension direction of the mounting groove 1121, and the length, width and height of the mounting flange 122 are approximately equal to the size of the mounting groove 1121, so that the mounting flange 122 can be limited and fitted within the mounting groove 1121, and the contact area between the mounting flange 122 and the mounting groove 1121 is guaranteed.

[0095] In some embodiments, the mounting groove 1121 extends away from the communication port 111, and the extension length of the mounting groove 1121 on the same side as the communication port 111 ranges from 0.5mm to 3mm. The extension length of the mounting groove 1121 can be understood as L1 as shown in Figure 2. When the extension length L1 is small, the connection strength between the cap 120 and the cover plate body 110 is reduced; when the extension length L1 is large, it not only increases the processing difficulty of the mounting flange 122 but also reduces the overall structural strength of the cover plate body 110.

[0096] Therefore, this disclosure sets the extension length of the mounting groove 1121 located on the same side of the connecting port 111 to 0.5mm to 3mm. While ensuring the connection strength between the cap 120 and the cover plate body 110, it also makes it easier to reduce the processing difficulty of the mounting flange 122, and ensures the structural strength of the cover plate body 110, thus extending the service life of the cover plate body 110.

[0097] In a specific example, the extension length of the mounting groove 1121 in the direction away from the connecting port 111 is 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.5mm, 2mm, 2.5mm or 3mm, etc.

[0098] In some embodiments, as shown in Figures 6 and 7, the protrusion 121 is provided with a plurality of explosion-proof valves 130. The plurality of explosion-proof valves 130 work together to increase the venting speed, thereby improving the safety of the battery cell 1000.

[0099] In some embodiments, as shown in Figures 6 and 7, the protrusion 121 is provided with two explosion-proof valves 130. The two explosion-proof valves 130 work together to increase the exhaust speed, and can also, to a certain extent, prevent the structural strength of the cap 120 from being reduced due to the installation of explosion-proof valves 130, extend the service life of the cap 120, and reduce the cost of use.

[0100] Of course, in some other embodiments, as shown in Figures 1 and 5, only one explosion-proof valve 130 may be provided on the protrusion 121.

[0101] In other examples, three, four, five or more explosion-proof valves 130 may be provided on the protrusion 121.

[0102] In some embodiments, as shown in Figures 1 and 3, at least one explosion-proof valve 130 is disposed on the wall surface of the protrusion 121 directly opposite the communication port 111. Since the gas inside the battery cell 1000 mainly enters the second receiving cavity 1211 through the communication port 111, the above arrangement ensures that the gas entering the second receiving cavity 1211 can effectively flow towards the explosion-proof valve 130. Thus, when the explosion-proof valve 130 is opened, it ensures that the gas inside the battery cell 1000 can be discharged through the explosion-proof valve 130, improving the safety of the battery cell 1000 in use.

[0103] Meanwhile, by placing the explosion-proof valve 130 on the wall surface of the protrusion 121 directly opposite the communication port 111, the liquid or gas sprayed from the explosion-proof valve 130 can be prevented from spraying onto the adjacent battery cell 1000 to a certain extent, thereby improving the safety performance of the battery pack.

[0104] Of course, in some other embodiments, the explosion-proof valve 130 may also be located on the outer peripheral wall of the protrusion 121 in the circumferential direction. That is to say, it is not limited to the explosion-proof valve 130 being located on the side wall of the protrusion 121 directly opposite the communication port 111. With the above-mentioned arrangement, the explosion-proof valve 130 can also be used to discharge the gas inside the battery cell 1000 to ensure the safety of the battery cell 1000 in use.

[0105] In some embodiments, as shown in Figures 1 and 5, at least one sidewall of the protrusion 121 has a through mounting port 1212, and an explosion-proof sheet 131 is installed in the mounting port 1212. The explosion-proof sheet 131 is formed as an explosion-proof valve 130. That is, the explosion-proof sheet 131 is installed on at least one sidewall of the protrusion 121 through the mounting port 1212 to form the explosion-proof valve 130. In this way, the safety of the battery cell 1000 can be improved by using the explosion-proof valve 130, while the molding difficulty of the explosion-proof valve 130 can be reduced.

[0106] In some embodiments, the explosion-proof valve 130 is connected to the mounting port 1212 by laser welding. This not only forms the explosion-proof valve 130, but also reduces the difficulty of fitting the explosion-proof valve 130 and the protrusion 121, and ensures the connection strength between the explosion-proof valve 130 and the protrusion 121, thereby improving the positional stability of the explosion-proof valve 130 and ensuring the working performance of the explosion-proof valve 130.

[0107] It should be noted that after laser welding, the explosion-proof valve 130 must be free of incomplete welds or weld holes and have the airtightness required by design.

[0108] It should also be noted that the explosion-proof valve 130 shown in Figure 1 has an elliptical shape. In other embodiments, the explosion-proof valve 130 can be designed into any geometric shape such as a circle, rectangle, triangle, trapezoid, ring or fan shape according to the actual process or performance requirements. This disclosure does not impose any specific limitations.

[0109] Of course, the shape of the mounting port 1212 must match the shape of the explosion-proof valve 130. That is to say, the shape of the mounting port 1212 can also be formed into any geometric shape such as ellipse, circle, rectangle, triangle, trapezoid, ring or fan, so as to facilitate the installation of the explosion-proof plate 131 into the mounting port 1212 and ensure the airtightness of the explosion-proof plate 131.

[0110] In some embodiments, as shown in Figures 6 and 7, at least one sidewall of the protrusion 121 is provided with a plurality of through mounting ports 1212. This allows for the provision of a plurality of explosion-proof valves 130 on at least one sidewall of the protrusion 121. The cooperation of the plurality of explosion-proof valves 130 can increase the venting speed, thereby improving the safety of the battery cell 1000.

[0111] Of course, in other embodiments, mounting ports 1212 can be provided through the protrusion 121 on multiple side walls to enable multiple explosion-proof valves 130 to be installed on the protrusion 121. This can also enable the use of multiple explosion-proof valves 130 to increase the exhaust speed and thus improve the safety of the battery cell 1000.

[0112] In some embodiments, the area of ​​the sidewall with the mounting port 1212 is S1, and the area of ​​the mounting port 1212 is S2, where S1 and S2 satisfy: 0.05 ≤ S2 / S1 ≤ 0.95. This ensures, on the one hand, that the area of ​​the mounting port 1212 on the sidewall is appropriate, thus ensuring that the area of ​​the explosion-proof valve 130 itself is suitable, improving the venting performance of the explosion-proof valve 130, thereby increasing the safety of the battery cell 1000 to a certain extent. On the other hand, it also ensures that the area occupied by the mounting port 1212 on the cap 120 is appropriate, thus avoiding a decrease in the structural strength of the cap 120 due to the mounting port 1212, thereby extending the service life of the cap 120.

[0113] In other words, this disclosure sets the area S1 of the side wall with the installation port 1212 and the area S2 of the installation port 1212 to satisfy: 0.05≤S2 / S1≤0.95. This ensures that the gas generated when the electrolyte is instantly vaporized can be smoothly discharged through the explosion-proof valve 130, while also ensuring that the explosion-proof valve 130 occupies a suitable space on the cap 120, which is beneficial to ensuring the structural strength of the cap 120.

[0114] In specific examples, S2 / S1 = 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, or 0.95, etc.

[0115] It should be noted that when multiple mounting openings 1212 are provided on the same side wall of the protrusion 121, the area S2 of the aforementioned mounting opening 1212 is the sum of the areas of the multiple mounting openings 1212, so as to avoid the structural strength of the cap 120 being low due to the opening of multiple mounting openings 1212, thereby extending the service life of the cap 120.

[0116] In some embodiments, the thickness of the explosion-proof sheet 131 ranges from 0.1 mm to 1.5 mm. When the explosion-proof sheet 131 is too thin, its structural strength decreases, its service life is shortened, and its performance is affected. When the explosion-proof sheet 131 is too thick, it cannot effectively rupture under high internal pressure within the battery cell 1000, thus reducing the safety of the battery cell 1000.

[0117] Therefore, the thickness of the explosion-proof sheet 131 is set to 0.1mm to 1.5mm. This ensures the structural strength of the explosion-proof sheet 131 while also ensuring that the explosion-proof sheet 131 can effectively rupture when the internal pressure of the battery cell 1000 is high. This facilitates the discharge of gas from the battery cell 1000 through the explosion-proof sheet 131, thereby achieving the function of pressure relief and explosion prevention and improving the safety of the battery cell 1000 in use.

[0118] In specific examples, the thickness of the explosion-proof sheet 131 is 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm or 1.5mm, etc.

[0119] Of course, in some other embodiments, the thickness of the explosion-proof sheet 131 can also be determined according to the explosion-proof pressure designed for each type of battery cell 1000.

[0120] In some embodiments, the explosion-proof plate 131 is provided with a first notch (not shown in the figure). The first notch can further ensure that the explosion-proof plate 131 is more easily detonated under the same gas production, thereby facilitating the opening of the explosion-proof valve 130 when the internal pressure of the battery cell 1000 reaches the upper limit, achieving the purpose of pressure relief, thereby ensuring the working performance of the explosion-proof valve 130.

[0121] The first notch mentioned here can be formed in the weak areas of the explosion-proof sheet 131 at different depths, strengths and rigidities by laser or other physical or chemical methods.

[0122] In addition, the first notch can be set on the outer surface of the explosion-proof sheet 131 or on the inner surface of the explosion-proof sheet 131, as long as it is ensured that the explosion-proof valve 130 can be opened when the internal pressure of the battery cell 1000 reaches the preset value, thereby improving the safety performance of the battery cell 1000.

[0123] In some embodiments, the cover assembly 100 further includes a protective sheet (not shown), which is disposed at the mounting opening 1212 and located on the side of the explosion-proof sheet 131 opposite to the second receiving cavity 1211. This is to protect the explosion-proof sheet 131 from damage caused by falling foreign objects, thereby ensuring the working performance of the explosion-proof sheet 131, reducing the risk of leakage due to external stress impacts or internal / external corrosion, and ensuring that the explosion-proof sheet 131 can effectively achieve rapid venting and pressure relief of the battery cell 1000, thus playing an explosion-proof role and solving the technical problem of spontaneous explosion of the battery cell 1000 to a certain extent.

[0124] Optionally, the protective sheet is made of materials such as PP (Polypropylene) or PET (Polyethylene terephthalate) to ensure that the protective sheet can be dissolved when heated, thereby ensuring that the protective sheet can be dissolved when the explosion-proof sheet 131 is vented due to thermal runaway, so that the gas can be discharged through the installation port 1212, ensuring the safety of the battery cell 1000.

[0125] In some embodiments, the protective sheet is bonded and fixed to the protrusion 121 to realize the protective sheet being placed in the mounting port 1212 and to realize the fixed connection between the protective sheet and the protrusion 121. At the same time, in the event of thermal runaway gas exhaust, the heat can be used to dissolve the connection between the protective sheet and the protrusion 121 to facilitate gas exhaust and further ensure the safety of the battery cell 1000.

[0126] In some embodiments, the thickness of the protective sheet ranges from 0.1 mm to 1.5 mm. Designing the thickness of the protective sheet within this range further enhances its performance, enabling it to effectively protect the explosion-proof sheet 131 and facilitating its melting upon heating, thereby improving venting efficiency.

[0127] Therefore, this disclosure sets the thickness of the protective sheet to a range of 0.1 mm to 1.5 mm. This ensures the working performance of the protective sheet and that it can effectively protect the explosion-proof sheet 131, while also allowing the protective sheet to dissolve when heated, facilitating gas discharge.

[0128] In specific examples, the thickness of the protective sheet is 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, or 1.5mm, etc.

[0129] In some embodiments, as shown in Figures 8 and 9, at least one sidewall of the protrusion 121 is provided with a second notch 1213, which is formed as an explosion-proof valve 130. That is, it is not limited to providing an installation port 1212 and an explosion-proof plate 131 on the protrusion 121; the second notch 1213 can also be provided on at least one sidewall of the protrusion 121. The second notch 1213 reduces the structural strength of part of the structure of the protrusion 121, thereby ensuring that when the internal pressure of the battery cell 1000 is high, part of the structure of the protrusion 121 can be effectively broken, thereby facilitating the discharge of gas inside the battery cell 1000, achieving the function of pressure relief and explosion prevention, and ensuring the safety performance of the battery cell 1000.

[0130] The second notch 1213 mentioned here can be formed in a weak area of ​​the protrusion 121 with different depths, strengths and rigidities by laser or other physical or chemical methods.

[0131] Furthermore, the second notch 1213 can be provided on the outer surface of the protrusion 121 or on the inner surface of the protrusion 121, as long as it ensures that the explosion-proof valve 130 can burst open when the internal pressure of the battery cell 1000 reaches the preset value, thereby improving the safety performance of the battery cell 1000.

[0132] In some embodiments, as shown in Figures 8-13, the second notch 1213 includes at least one arc-shaped notch and / or at least one straight notch. This means that the second notch 1213 includes at least one arc-shaped notch; or, the second notch 1213 includes at least one straight notch; or, the second notch 1213 includes at least one arc-shaped notch and at least one straight notch, meaning the second notch 1213 can be composed of a combination of at least one arc-shaped notch and at least one straight notch.

[0133] In some embodiments, as shown in Figures 8 and 9, the second notch 1213 includes two arc-shaped notches.

[0134] Of course, in some other embodiments, the second notch 1213 may also include an arc-shaped notch; or, the second notch 1213 may be composed of an arc-shaped notch and at least one straight notch.

[0135] In other embodiments, as shown in Figures 10, 11, 12 and 13, the second notch 1213 includes a straight notch, and the second notch 1213 may also be composed of multiple straight notches, which may form a closed shape or an open shape.

[0136] Figures 10, 11, and 12 show examples of the second notch 1213 consisting of an open shape composed of multiple straight notches, while Figure 13 shows an example of the second notch 1213 consisting of a closed shape composed of multiple straight notches.

[0137] When the second notch 1213 is composed of multiple straight notches forming a closed shape, the overall shape of the second notch 1213 after forming can also be a triangle (as shown in Figure 13), a rectangle, or a trapezoid, etc.; when the second notch 1213 is composed of multiple straight notches forming an open shape, the overall shape of the second notch 1213 after forming can be seen in Figures 10, 11, and 12.

[0138] In some embodiments, the thickness of the sidewall with the second notch 1213 is greater than 0.2 mm. Here, the thickness of the sidewall with the second notch 1213 can be understood as L2 shown in FIG14. By limiting the above thickness, the structural strength of the protrusion 121 can be guaranteed to a certain extent, thereby preventing the protrusion 121 from bursting prematurely and ensuring the working performance of the protrusion 121.

[0139] In some embodiments, as shown in Figures 15 and 16, at least one sidewall of the protrusion 121 is provided with a plurality of second grooves 1213. This allows for the provision of a plurality of explosion-proof valves 130 on at least one sidewall of the protrusion 121. The cooperation of the plurality of explosion-proof valves 130 can increase the venting speed, thereby improving the safety of the battery cell 1000.

[0140] Of course, in some other embodiments, second grooves 1213 may be provided on multiple sidewalls of the protrusion 121 to enable multiple explosion-proof valves 130 to be provided on the protrusion 121. In this way, multiple explosion-proof valves 130 can be used in conjunction to increase the exhaust speed, thereby improving the safety of the battery cell 1000.

[0141] In some embodiments, the area of ​​the sidewall with the second notch 1213 is S1, and the coverage area of ​​the projection of the second notch 1213 onto the first plane is S3. S1 and S3 satisfy: 0.05≤S3 / S1≤0.95, and the first plane is perpendicular to the thickness direction of the cover body 110. This ensures that the area of ​​the second notch 1213, i.e. the area of ​​the explosion-proof valve 130 itself, is appropriate, improving the venting performance of the explosion-proof valve 130 and thus increasing the safety of the battery cell 1000 to a certain extent. On the other hand, it also ensures that the area occupied by the second notch 1213 on the cap 120 is appropriate, avoiding the lower structural strength of the cap 120 due to the second notch 1213, thereby extending the service life of the cap 120.

[0142] In other words, this disclosure sets the area S1 of the sidewall with the second notch 1213 and the coverage area S3 of the projection of the second notch 1213 on the first plane to satisfy: 0.05≤S2 / S1≤0.95. This ensures that the gas generated when the electrolyte is instantly vaporized can be smoothly discharged through the explosion-proof valve 130, while also ensuring that the explosion-proof valve 130 occupies a suitable space on the cap 120, which is beneficial to ensuring the structural strength of the cap 120.

[0143] In specific examples, S2 / S1 = 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, 0.4, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, or 0.95, etc.

[0144] It should be noted that when multiple second notches 1213 are provided on the same side wall of the protrusion 121, the coverage area S3 of the projection of the aforementioned second notches 1213 on the first plane is the sum of the coverage areas of the projections of the multiple second notches 1213, so as to avoid the structural strength of the cap 120 being low due to the opening of multiple second notches 1213, thereby extending the service life of the cap 120.

[0145] In some embodiments, as shown in FIG3, the thickness W of the cap 120 ranges from 0.3mm to 5mm. When the thickness W of the cap 120 is thin, the structural strength of the cap 120 is reduced; when the thickness W of the cap 120 is thick, not only is the manufacturing cost of the cap 120 increased, but the weight of the cap 120 is also increased, which is not conducive to achieving a lightweight design of the battery cell 1000.

[0146] Therefore, this disclosure sets the thickness W of the cap 120 to 0.3mm to 5mm, which can reduce the manufacturing cost of the cap 120 while ensuring the structural strength of the cap 120, and can achieve a lightweight design of the battery cell 1000.

[0147] In specific examples, the thickness W of the cap 120 is 0.3mm, 0.4mm, 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm or 5mm.

[0148] Optionally, as shown in Figure 3, the protrusion height H1 of the protrusion 121 ranges from 2mm to 50mm. When the protrusion height H1 of the protrusion 121 is low, the accommodating space of the second receiving cavity 1211 is reduced, making it impossible to ensure that at least a portion of the tab 300 can be effectively assembled within the cover assembly 100, which is detrimental to improving the energy density of the battery cell 1000. When the protrusion height H1 of the protrusion 121 is high, the size of the cover assembly 100 is increased, thereby increasing the size of the battery cell 1000.

[0149] Therefore, the present disclosure sets the value of the protrusion height H1 of the protrusion 121 in the range of 2mm to 50mm. While ensuring the accommodating space of the second accommodating cavity 1211, it also facilitates the reduction of the size of the battery cell 1000, thereby increasing the energy density of the battery cell 1000.

[0150] In some embodiments, the protrusion height H1 of the protrusion 121 ranges from 2 mm to 10 mm to further optimize the size of the protrusion 121.

[0151] In a specific example, the protrusion height H1 of the protrusion 121 is 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm or 10mm.

[0152] In some embodiments, on the first plane, the projected area of ​​the connecting opening 111 is S1, and the projected area of ​​the cover plate body 110 excluding the connecting opening 111 is S4. S1 and S4 satisfy: 0.1≤S1 / S4≤3, and the first plane is perpendicular to the thickness direction of the cover plate body 110. When the area of ​​the connecting opening 111 is smaller than the area of ​​the cover plate body 110, it is not conducive to assembling at least a portion of the tab 300 within the cover plate assembly 100. When the area of ​​the connecting opening 111 is larger than the area of ​​the cover plate body 110, it reduces the structural strength of the cover plate body 110.

[0153] In this disclosure, the projected area S1 of the connecting port 111 and the projected area S4 of the cover plate body 110 excluding the connecting port 111 are set to satisfy: 0.1≤S1 / S4≤3. This ensures that at least a portion of the tab 300 can be assembled in the cover plate assembly 100, while also ensuring the structural strength of the cover plate body 110, thereby ensuring the working performance of the cover plate assembly 100.

[0154] In specific examples, S1 / S4 = 0.1, 0.5, 1, 1.5, 2, 2.5 or 3, etc.

[0155] In some embodiments, the opening pressure D of the explosion-proof valve 130 ranges from 0.15 MPa to 3 MPa to ensure the working performance of the explosion-proof valve 130.

[0156] In some embodiments, as shown in FIG1, the cover plate assembly 100 further includes a pole post assembly 140, which is disposed on the cover plate body 110. That is, in addition to the communication port 111, the cover plate body 110 is also provided with the pole post assembly 140. By placing the pole post assembly 140 on the cover plate body 110, the cover plate body 110 can support the pole post assembly 140, thereby improving the positional stability of the pole post assembly 140 and ensuring the working performance of the pole post assembly 140.

[0157] In some embodiments, the battery cell 1000 has a core, and the terminal assembly 140 is adapted to be electrically connected to the core so as to draw out the current of the core using the terminal assembly 140 to ensure the working performance of the core.

[0158] In some embodiments, the cover plate body 110 is provided with an assembly port, and the pole post assembly 140 is provided at the assembly port, so that the pole post assembly 140 can be provided on the cover plate body 110, thereby facilitating the use of the cover plate body 110 to support the pole post assembly 140, improving the positional stability of the pole post assembly 140, and reducing the difficulty of fitting the pole post assembly 140 with the cover plate body 110.

[0159] It should be noted that by placing the pole post assembly 140 on the cover plate body 110, the pole post assembly 140 can be avoided from occupying space on the cap 120. While reducing the difficulty of forming the cap 120, it can also ensure that there is enough space on the cap 120 to set the pole post assembly 140.

[0160] Optionally, the protrusion height H1 of the protrusion 121 and the height H2 of the terminal assembly 140 protruding from the cover plate body 110 satisfy: -5mm ≤ H1 - H2 ≤ 5mm. This means that in the protrusion direction of the protrusion 121, the protrusion 121 can protrude from the terminal assembly 140, be flush with the terminal assembly 140, or be lower than the terminal assembly 140. When the protrusion 121 protrudes from the terminal assembly 140, the height of the protrusion 121 from the terminal assembly 140 should not be too high, so as to avoid excessively increasing the size of the battery cell 1000 due to the protrusion 121, thereby ensuring the size of the battery cell 1000. When the protrusion 121 is lower than the terminal assembly 140, the protrusion 121 should not be too low, so as to ensure the accommodating space of the second receiving cavity 1211, ensuring that at least a portion of the tab 300 can be effectively assembled within the cover plate assembly 100, thereby improving the energy density of the battery cell 1000.

[0161] In some embodiments, H1-H2 = -5mm, -4mm, -3mm, -2mm, -1mm, 0mm, 1mm, 2mm, 3mm, 4mm or 5mm, etc.

[0162] In some embodiments, the cover assembly 100 further includes an injection hole (not shown in the figure), which is provided on the cover body 110 and / or the protrusion 121, and communicates with the first receiving cavity 210. This means that the injection hole can be provided on the cover body 110, on the protrusion 121, or both on the cover body 110 and the protrusion 121. By providing the injection hole, it is possible to inject liquid into the battery cell 100 through the cover assembly 100 after the battery cell 100 is assembled, reducing the difficulty of liquid injection while ensuring the working performance of the battery cell 1000.

[0163] In some embodiments, the injection hole is connected to the second receiving cavity 1211. By configuring the injection hole to be connected to the second receiving cavity 1211, a portion of the electrolyte can be stored in the second receiving cavity 1211 during the injection process, which can be used for faster injection and reduce the number of injections.

[0164] The battery casing 600 of this disclosure is described below with reference to the accompanying drawings.

[0165] As shown in FIG1, a battery housing 600 according to an embodiment of the present disclosure includes: a housing 200 and a cover assembly 100.

[0166] As shown in Figures 1 and 3, a first receiving cavity 210 with an opening 211 is formed inside the outer casing 200, and the first receiving cavity 210 is suitable for placing the electrode core. This allows the electrode core to be placed inside the outer casing 200, which facilitates the protection of the electrode core by the outer casing 200, extends the service life of the electrode core, and improves the safety of the electrode core in use.

[0167] As shown in Figure 1, the cover plate assembly 100 is the aforementioned cover plate assembly 100. The specific structure of the cover plate assembly 100 will not be described in detail here. The cover plate assembly 100 is located at the opening 211.

[0168] As can be seen from the above structure, the battery casing 600 of this embodiment, by adopting the aforementioned cover assembly 100, when the battery casing 600 is applied to the battery cell 1000, can achieve a high volumetric energy density of the battery cell 1000, while also ensuring the safety of the battery cell 1000 to a certain extent.

[0169] In some embodiments, the housing 200 is formed by stamping or welding, and the material of the housing 200 is aluminum or steel, etc.

[0170] The battery cell 1000 of this disclosure is described below with reference to the accompanying drawings.

[0171] As shown in Figure 1, a battery cell 1000 according to an embodiment of the present disclosure includes: an electrode core and a cover plate assembly 100 or a battery casing 600.

[0172] At least a portion of the electrode tab 300 of the electrode core is disposed within the second receiving cavity 1211.

[0173] As can be seen from the above structure, the battery cell 1000 of this embodiment, by adopting the aforementioned cover plate assembly 100, can achieve high volumetric energy density of the battery cell 1000 while also ensuring the safety of the battery cell 1000 to a certain extent.

[0174] In a specific example, during the assembly of the battery cell 1000, the tab 300 is first led out to the outside of the housing 200 through the connecting port 111 on the surface of the cover body 110 for welding, and then the cap 120 is fixedly connected to the cover body 110 to realize the assembly of at least part of the tab 300 in the second receiving cavity 1211.

[0175] In some embodiments, as shown in FIG3, the tab 300 and the cap 120 are spaced apart, and the minimum distance between the tab 300 and the cap 120 ranges from 1mm to 10mm. The minimum distance between the tab 300 and the cap 120 can be understood as L3 shown in FIG3. This ensures the size of the tab 300 while also preventing electrical connection between the tab 300 and the cap 120 to a certain extent, thereby ensuring the safety of the battery cell 1000 in use.

[0176] In some embodiments, as shown in FIG3, the battery cell 1000 further includes an insulating member 500, which is disposed between the cover plate body 110 and the electrode core to avoid electrical connection between the cover plate body 110 and the electrode core to a certain extent, thereby further ensuring the safety of the battery cell 1000 in use.

[0177] The following describes a battery pack according to an embodiment of the present disclosure.

[0178] A battery pack according to an embodiment of the present disclosure includes: a plurality of battery cells 1000.

[0179] Among them, the battery cell 1000 is the aforementioned battery cell 1000, and the specific structure of the battery cell 1000 will not be described in detail here.

[0180] As can be seen from the above structure, the battery pack of this embodiment, by adopting the aforementioned battery cell 1000, is beneficial to improving the energy density of the battery pack and ensuring the safety of the battery pack in use.

[0181] In some embodiments, the battery pack includes a housing assembly, in which a plurality of battery cells 1000 are disposed to form the battery pack. The housing assembly is mainly used to protect and support the plurality of battery cells 1000 to improve the positional stability of the battery cells 1000, ensure the working performance of the battery cells 1000, extend the service life of the battery cells 1000, and improve the safety of the battery cells 1000 in use, so as to further ensure the working performance of the battery pack.

[0182] The following describes an electrical device according to an embodiment of this disclosure.

[0183] An electrical device according to an embodiment of the present disclosure includes: a battery pack.

[0184] The battery pack is the same as the one mentioned above; its specific structure will not be described in detail here.

[0185] As can be seen from the above structure, the electrical device of this disclosure, by adopting the aforementioned battery pack, is beneficial to improving the working performance of the electrical device and ensuring the safety of its use.

[0186] It should be noted that the electrical devices mentioned here can include, but are not limited to, mobile phones, tablets, laptops, electric toys, power tools, electric vehicles, electric cars, ships, spacecraft, etc.

[0187] 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; spacecraft can include airplanes, rockets, space shuttles, and spacecraft; 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.

[0188] It should also be noted that when the electrical device is used in vehicles such as electric vehicles or electric cars, the aforementioned battery pack can effectively increase the vehicle's range, thereby improving the driving experience.

[0189] In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.

[0190] Figures 6 and 7 show two mounting ports 1212 for illustrative purposes. However, after reading the above technical solution, a person skilled in the art will obviously understand that the solution can be applied to a technical solution with three or more mounting ports 1212, which also falls within the protection scope of this disclosure.

[0191] Other components of the battery cell 1000, including the cover assembly 100, battery housing 600, battery cell 1000, battery pack, and power device according to embodiments of this disclosure, are known to those skilled in the art and will not be described in detail here.

[0192] In the description of this specification, references to terms such as "embodiment," "example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this disclosure. In this specification, 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.

[0193] Although embodiments of this disclosure have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this disclosure, the scope of which is defined by the claims and their equivalents.

Claims

1. A cover plate assembly for a single battery cell, characterized in that, The application relates to a battery cell cover plate, which comprises: a cover plate body (110) adapted to connect the shell (200) of the battery cell, the cover plate body (110) being provided with a communication port (111) penetrating the cover plate body (110), the communication port (111) being adapted to communicate with a first accommodating cavity (210) of the shell (200), and the first accommodating cavity (210) being adapted to place a pole core; a cover cap (120) provided on the cover plate body (110) and opposite to the communication port (111), the cover cap (120) being fixedly connected with the cover plate body (110), at least a part of the cover cap (120) being protruded away from the communication port (111) to form a protruding part (121), a side of the protruding part (121) facing the communication port (111) forming a second accommodating cavity (1211) communicating with the communication port (111), the second accommodating cavity (1211) being used for buffering gas, and at least one explosion-proof valve (130) being arranged on the protruding part (121), the explosion-proof valve (130) being configured to be broken to communicate the second accommodating cavity (1211) when a set pressure is reached inside the pole core.

2. The cover plate assembly of claim 1, wherein, The second accommodating cavity (1211) is used for accommodating at least a part of a tab (300) of the battery cell.

3. The cover plate assembly of claim 1, wherein, A plurality of the explosion-proof valves (130) are arranged on the protruding part (121).

4. The cover plate assembly of claim 1, wherein, At least one of the explosion-proof valves (130) is arranged on a wall surface of the protruding part (121) opposite to the communication port (111).

5. The cover plate assembly of claim 1, wherein, At least one side wall of the protruding part (121) is provided with a mounting port (1212) penetrating the side wall, and an explosion-proof sheet (131) is mounted in the mounting port (1212), the explosion-proof sheet (131) being formed as the explosion-proof valve (130).

6. The cover plate assembly of claim 5, wherein, The area of the side wall provided with the mounting port (1212) is S1, and the area of the mounting port (1212) is S2, and the S1 and the S2 satisfy 0.05<=S2 / S1<=0.

95.

7. The cover plate assembly of claim 5, wherein, The explosion-proof sheet (131) is provided with a first notch.

8. The cover plate assembly of claim 5, wherein, A protection sheet is further arranged on the mounting port (1212) and located on a side of the explosion-proof sheet (131) away from the second accommodating cavity (1211).

9. The cover plate assembly of claim 8, wherein, The thickness of the protection sheet ranges from 0.1mm to 1.5mm.

10. The cover plate assembly of claim 1, wherein, At least one side wall of the protruding part (121) is provided with a second notch (1213), and the second notch (1213) is formed as the explosion-proof valve (130).

11. The cover plate assembly of claim 10, wherein, The second notch (1213) comprises at least one arc-shaped notch and / or at least one straight-line notch.

12. The cover plate assembly of claim 10, wherein, The thickness of the side wall provided with the second notch (1213) is greater than 0.2mm.

13. The cover plate assembly of claim 10, wherein, The area of the side wall provided with the second notch (1213) is S1, the covering area of the projection of the second notch (1213) on a first plane is S3, the S1 and the S3 satisfy 0.05<=S3 / S1<=0.95, and the first plane is perpendicular to the thickness direction of the cover plate body (110).

14. The cover plate assembly of claim 1, wherein, The thickness W of the cover cap (120) ranges from 0.3mm to 5mm. And / or, the protruding height H1 of the protruding part (121) ranges from 2mm to 50mm.

15. The cover plate assembly of claim 1, wherein, On a first plane, the projection area of the communication port (111) is S1, and the projection area of the cover plate body (110) excluding the communication port (111) is S4, and the S1 and the S4 satisfy: 0.1≤S1 / S4≤3, and the first plane is perpendicular to the thickness direction of the cover plate body (111).

16. The cover plate assembly of claim 1, wherein, Further comprising a pole post assembly (140), which is arranged on the cover plate body (110). The protruding height H1 of the protruding part (121) and the height H2 of the pole post assembly (140) protruding from the cover plate body (110) satisfy: -5mm≤H1-H2≤5mm.

17. The cover plate assembly of the battery cell according to any one of claims 1-16, wherein, Further comprising a liquid injection hole, which is arranged on the cover plate body (110) and / or the protruding part (121), and which communicates with the first accommodating cavity (210).

18. The cover plate assembly of the battery cell according to any one of claims 1-16, wherein, In the protruding direction of the protruding part (121), the first side wall (112) of the cover plate body (110) is provided with a mounting groove (1121), and the cover cap (120) has a mounting flange (122) matched with the mounting groove (1121), and the mounting flange (122) is limited in the mounting groove (1121).

19. The cover plate assembly of claim 18, wherein, The mounting groove (1121) is arranged around the outer periphery of the communication port (111) and communicates with the communication port (111), and the shape of the mounting flange (122) matches the shape of the mounting groove (1121).

20. The cover plate assembly of claim 18, wherein, The mounting groove (1121) extends away from the communication port (111), and the extension length of the mounting groove (1121) located on the same side of the communication port (111) ranges from 0.5mm to 3mm.

21. A battery case characterized by, It comprises: A shell (200) in which a first accommodating cavity (210) with an opening (211) is formed, and the first accommodating cavity (210) is suitable for placing a pole core; A cover plate assembly (100) according to any one of claims 1-20, which is arranged at the opening (211).

22. A battery cell, characterized by It comprises a pole core and a cover plate assembly (100) according to any one of claims 1-20 or a battery shell (600) according to any one of claim 21, and at least part of the tab (300) of the pole core is arranged in the second accommodating cavity (1211).

23. The battery cell of claim 22, wherein, The tab (300) is arranged apart from the cover cap (120), and the minimum distance between the tab (300) and the cover cap (120) ranges from 1mm to 50mm.

24. A battery pack, characterized by It comprises a plurality of battery monomers according to claim 22 or 23.

25. An electrical device, comprising: It comprises a battery pack according to claim 24.

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