Battery and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery and a battery pack, and the battery comprises a shell, a cover plate assembly, a pole group and a supporting structure, the shell is provided with an accommodating cavity and an open end; the cover plate assembly is arranged at the open end of the shell, and the cover plate assembly is provided with an anti-explosion structure; the pole group is arranged in the accommodating cavity, and a pressure relief channel communicated with the explosion-proof structure is arranged between the pole group and the cover plate assembly; and the supporting structure is arranged in the pressure relief channel and is connected with the pole group. According to the battery provided by the utility model, due to the arrangement of the supporting structure, when the battery is subjected to thermal runaway, the battery can be supported between the cover plate assembly and the pole group, so that the pole group is prevented from moving and blocking the anti-explosion structure under the pushing of airflow, the anti-explosion structure is enabled to smoothly release pressure and prevent the thermal runaway from spreading, and the safety performance of the battery is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, in particular to batteries and battery packs. Background Art

[0002] As lithium-ion battery technology matures, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage fields, and the requirements for the performance and safety of lithium-ion batteries are increasing. In traditional square lithium batteries, the cover assembly and the shell are welded and sealed to encapsulate the electrode group inside, and the lower plastic in the cover assembly presses against the electrode group to limit the position of the electrode group.

[0003] In the traditional battery structure, when the lithium battery thermal runaway occurs, the temperature inside the battery is too high, and the gas production inside the battery is too high, reaching the triggering condition. The explosion-proof valve opens, and the gas produced inside the battery is discharged quickly. There is a risk of the electrode group being pushed upward by the airflow. At this time, the battery runaway temperature is too high, and the lower plastic is usually made of PP material with a melting point of 160°C. It will completely melt at high temperature and lose its limiting effect on the electrode group. After the electrode group is pushed up by the airflow, there is a risk of clogging the explosion-proof valve, accelerating the battery runaway and posing a safety risk. Utility Model Content

[0004] In view of this, the utility model provides a battery and a battery pack to solve the problem that the explosion-proof valve is blocked and the battery loses control faster.

[0005] In the first aspect, the utility model provides a battery, including a shell, a cover assembly, a pole group and a support structure. The shell has a housing cavity and an open end; the cover assembly is arranged at the open end of the shell, and the cover assembly is provided with an explosion-proof structure; the pole group is arranged in the housing cavity, and a pressure relief channel connected to the explosion-proof structure is arranged between the pole group and the cover assembly; the support structure is arranged in the pressure relief channel, and the support structure is connected to the pole group.

[0006] Beneficial effect: Due to the provision of a support structure, when thermal runaway occurs in the battery, it can be supported between the cover assembly and the pole group to prevent the pole group from moving under the push of the airflow and blocking the explosion-proof structure, so that the explosion-proof structure can be depressurized smoothly and the thermal runaway can be prevented from spreading, thereby improving the safety performance of the battery.

[0007] In an optional embodiment, when projected along the direction from the cover plate assembly to the pole group, the projection surface of the support structure at least partially does not overlap with the projection surface of the explosion-proof structure.

[0008] Beneficial effect: With this arrangement, when the temperature inside the battery rises and the lower plastic and other structural parts that limit the electrode group melt, the support structure can be supported between the cover assembly and the electrode group, thereby ensuring that the support structure can maintain the unobstructed flow from the pressure relief channel to the explosion-proof structure, ensuring that the explosion-proof structure is not blocked by the electrode group, and achieving smooth exhaust and pressure relief.

[0009] In an optional embodiment, the support structure is arranged on the periphery of the explosion-proof structure.

[0010] Beneficial effect: With this arrangement, when projected from the cover assembly to the electrode group, the support structure and the explosion-proof structure do not overlap at all. When the lower plastic and other structural parts that limit the electrode group melt due to thermal runaway inside the battery, the support structure is supported between the cover assembly and the electrode group, and the support structure is more reliable.

[0011] In an optional embodiment, the support structure is located between the explosion-proof structure and the pole group, and at least one dimension of the support structure is larger than a dimension of the explosion-proof structure in the same direction.

[0012] Beneficial effect: With this arrangement, when thermal runaway occurs, after the support structure and the pole group are lifted up by the airflow, the support structure can abut against the cover plate assembly and will not fly out of the explosion-proof valve.

[0013] In an optional embodiment, the support structure is a square structure, and along the width direction of the cover assembly, the width of the support structure is greater than the width of the explosion-proof structure; or, along the length direction of the cover assembly, the length of the support structure is greater than the length of the explosion-proof structure.

[0014] Beneficial effects: This arrangement has a simple structure, low cost, and can achieve effective support to prevent the explosion-proof structure from being blocked.

[0015] In an optional embodiment, the supporting structure includes a pad, and the thickness of the pad is not less than 3 mm.

[0016] Beneficial effect: The support structure is set as a pad, which has a simple structure and is easy to process and assemble. The thickness of the pad is not less than 3mm, which can ensure that when thermal runaway occurs, the pad can effectively support the pole group, maintain the pressure relief channel, ensure that the explosion-proof structure is not blocked by the pole group, and can smoothly exhaust and relieve pressure.

[0017] In an optional embodiment, the spacer is connected to the pole group via a fixing belt.

[0018] Beneficial effects: This arrangement makes the connection convenient, firm and reliable, and the assembly quick.

[0019] In an optional embodiment, the fixing tape comprises an adhesive tape or a PP soft tape patch, the middle portion of the fixing tape is adhered to the cushion block, and the rest of the fixing tape is adhered to at least two opposite sides of the pole group.

[0020] Beneficial effect: This arrangement can firmly connect the pad and the pole group, ensuring effective pre-tightening force on the pad.

[0021] In an optional embodiment, a gap is left between the supporting structure and the cover plate assembly.

[0022] Beneficial effect: This arrangement can prevent wear between the support structure and the cover assembly caused by battery collision and other factors, thereby affecting the fixing effect between the support structure and the pole group.

[0023] In a second aspect, the utility model also provides a battery pack, comprising a battery according to any one of the above technical solutions.

[0024] Since the battery pack includes batteries and has the same effects as the batteries, they will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A top view of a battery according to an embodiment of the utility model;

[0027] Figure 2 For along Figure 1 Sectional view at AA in the middle;

[0028] Figure 3 The figure is a schematic diagram of the exploded structure of a battery according to an embodiment of the present utility model.

[0029] Description of reference numerals:

[0030] 1. Shell; 2. Cover assembly; 3. Pole group; 4. Support structure; 401. Pad; 402. Fixing belt; 5. Explosion-proof structure; 6. Pole. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiment of the utility model clearer, the technical solution in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all the embodiments. Based on the embodiment of the utility model, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the utility model.

[0032] Combine the following Figures 1 to 3 , describing an embodiment of the utility model.

[0033] According to an embodiment of the utility model, on the one hand, a battery is provided, comprising a housing 1, a cover assembly 2, a pole group 3 and a support structure 4. The housing 1 has a receiving cavity and an open end; the cover assembly 2 is arranged at the open end of the housing 1, and the cover assembly 2 is provided with an explosion-proof structure 5; the pole group 3 is arranged in the receiving cavity, and a pressure relief channel connected to the explosion-proof structure 5 is arranged between the pole group 3 and the cover assembly 2; the support structure 4 is arranged in the pressure relief channel, and the support structure 4 is connected to the pole group 3.

[0034] Since a pressure relief channel is provided between the pole group 3 and the cover plate assembly 2, and the pressure relief channel is connected to the explosion-proof structure 5, when the battery has thermal runaway, the gas can move from the pressure relief channel to the explosion-proof structure 5 to open and release the pressure. Since the support structure 4 is provided in the pressure relief channel, when the battery has thermal runaway, the temperature inside the housing 1 quickly reaches a high temperature, and the lower plastic and other structural parts that originally limit the pole group 3 melt, the pole group 3 loses its limit, and the pressure in the pressure relief channel is small. The generated gas acts on the pole group 3, which will push the pole group 3 to move toward the cover plate assembly 2. Since the support structure 4 is connected to the pole group 3, it will drive the support structure 4 to move toward the cover plate assembly 2. At this time, the support structure 4 abuts against the cover plate assembly 2 and is supported between the pole group 3 and the cover plate assembly 2, which can maintain the pressure relief channel, so that the pressure relief channel and the explosion-proof structure 5 are still in a connected state, and the gas enters the pressure relief channel and smoothly reaches the explosion-proof structure 5, and the explosion-proof structure 5 explodes to release the pressure, preventing the spread of thermal runaway, thereby improving the safety performance of the battery. Since the support structure 4 is provided, when thermal runaway occurs in the battery, it can be supported between the cover plate assembly 2 and the pole group 3 to prevent the pole group 3 from moving under the push of the airflow and blocking the explosion-proof structure 5, so that the explosion-proof structure 5 can release pressure smoothly.

[0035] Specifically, since the temperature inside the housing 1 is high when the battery undergoes thermal runaway, the support structure 4 is made of a high temperature resistant material. At the same time, since the support structure 4 is in direct contact with the electrolyte, the support structure 4 must also be resistant to electrolyte corrosion. Finally, since the support structure 4 is directly connected to the pole group 3, in order to prevent a short circuit, the support structure 4 must also be made of an insulating material. In one embodiment, the material of the support structure 4 includes ceramics or high temperature resistant rubber, wherein the high temperature resistant rubber includes fluororubber.

[0036] In one embodiment, when projected from the cover plate assembly 2 to the pole group 3 , the projection surface of the support structure 4 at least partially does not overlap with the projection surface of the explosion-proof structure 5 .

[0037] In this way, when the temperature inside the battery rises and the lower plastic and other structural parts that limit the electrode group 3 melt, the support structure 4 can be supported between the cover plate assembly 2 and the electrode group 3. The support structure 4 at least partially does not overlap with the explosion-proof structure 5, which can be achieved by dislocation of the explosion-proof structure 5 and the support structure 4 in position or by different shapes of the explosion-proof structure 5 and the support structure 4, thereby ensuring that the support structure 4 can keep the pressure relief channel from the explosion-proof structure 5 unobstructed, ensuring that the explosion-proof structure 5 is not blocked by the electrode group 3, and achieving smooth exhaust and pressure relief.

[0038] In one embodiment, the support structure 4 is disposed on the periphery of the explosion-proof structure 5 .

[0039] Specifically, the periphery of the explosion-proof structure 5 refers to that, when projected along the direction from the cover plate assembly 2 to the pole group 3 , the projection surface of the explosion-proof structure 5 and the projection surface of the support structure 4 do not overlap at all.

[0040] In this way, when projected from the cover plate assembly 2 to the electrode group 3, the support structure 4 and the explosion-proof structure 5 do not overlap at all. When the lower plastic and other structural parts that limit the electrode group 3 melt due to thermal runaway inside the battery, the support structure 4 is supported between the cover plate assembly 2 and the electrode group 3, and the support structure 4 is more reliable.

[0041] In one embodiment, the support structure 4 is located between the explosion-proof structure 5 and the pole group 3 , and at least one dimension of the support structure 4 is larger than a dimension of the explosion-proof structure 5 in the same direction.

[0042] In this arrangement, since the projection surface of the support structure 4 does not overlap with the projection surface of the explosion-proof structure 5 at least partially when projected from the cover plate assembly 2 to the pole group 3, there is a gap between the support structure 4 and the explosion-proof structure 5, so that even if the support structure 4 is arranged directly below the explosion-proof structure 5, the support structure 4 will not block the explosion-proof structure 5, and the support structure 4 can still support the pole group 3 and the cover plate assembly 2 and maintain the pressure relief channel between the pole group 3 and the cover plate assembly 2. Since at least one dimension of the support structure 4 is larger than the dimension of the explosion-proof structure 5 in the same direction, when thermal runaway occurs, after the support structure 4 and the pole group 3 are lifted up by the airflow, the support structure 4 can abut against the cover plate assembly 2 and will not fly out of the explosion-proof valve.

[0043] In one embodiment, the support structure 4 is a square structure, and along the width direction of the cover assembly 2, the width of the support structure 4 is greater than the width of the explosion-proof structure 5; or, along the length direction of the cover assembly 2, the length of the support structure 4 is greater than the length of the explosion-proof structure 5.

[0044] When the support structure 4 is a square structure, there are two implementations. First, the width of the support structure 4 is greater than the width of the explosion-proof structure 5, so that when thermal runaway occurs, the two ends of the support structure 4 in the width direction can abut against the cover assembly 2, support the pole group 3, and keep the pressure relief channel and the explosion-proof structure 5 connected. Second, the length of the support structure 4 is greater than the length of the explosion-proof structure 5. In this way, when thermal runaway occurs, the two ends of the support structure 4 in the length direction can abut against the cover assembly 2, support the pole group 3, and also keep the pressure relief channel and the explosion-proof structure 5 connected.

[0045] This arrangement has a simple structure and low cost, and can provide effective support to prevent the explosion-proof structure 5 from being blocked.

[0046] In one embodiment, the support structure 4 includes a cushion block 401 , and the thickness of the cushion block 401 is not less than 3 mm.

[0047] The support structure 4 is set as a cushion block 401, which has a simple structure and is easy to process and assemble. The thickness of the cushion block 401 is not less than 3 mm, so that when thermal runaway occurs, the cushion block 401 can effectively support the pole group 3, maintain the pressure relief channel, ensure that the explosion-proof structure 5 is not blocked by the pole group 3, and can smoothly exhaust and relieve pressure.

[0048] Specifically, the total thickness of the cushion block 401 is calculated to meet the requirement that: the cross-sectional area of ​​the pressure relief channel is greater than the exhaust area of ​​the explosion-proof structure 5. The cross-sectional area of ​​the pressure relief channel is the space between the cover plate assembly 2 and the pole group 3 excluding the explosion-proof structure 5.

[0049] In one embodiment, the spacer 401 is connected to the pole group 3 via a fixing belt 402 .

[0050] This arrangement is convenient to connect, firm and reliable, and quick to assemble. Compared with the technical solution of connecting the support structure to the cover assembly, in this embodiment, the support structure 4, that is, the pad 401 is connected to the pole group 3 through the fixing belt 402, which is convenient to connect, does not require welding and other operations, has a simple process, is easy to assemble, and has low cost.

[0051] In one embodiment, the fixing tape 402 includes an adhesive tape or a PP soft tape patch, the middle portion of the fixing tape 402 is adhered to the cushion block 401 , and the rest of the fixing tape 402 is adhered to at least two opposite sides of the electrode group 3 .

[0052] Specifically, in one embodiment, the middle of the fixing belt 402 is attached to the cushion block 401, and the two ends of the fixing belt 402 are attached to the two opposite sides of the pole group 3, respectively, and the fixing belt 402 is U-shaped as a whole. Of course, the fixing belt 402 can also be wrapped around the pole group 3, so that the fixing is more secure.

[0053] This arrangement can firmly connect the cushion block 401 and the pole group 3 , thereby ensuring an effective pre-tightening force on the cushion block 401 .

[0054] Specifically, the fixing belt 402 is made of electrolyte-resistant material and resistant to the melting temperature of plastic at 160°C, so that the fixing belt 402 will not melt when the battery does not trigger thermal runaway, and a firm connection between the pad 401 and the electrode group 3 is still ensured. In one embodiment, the material of the fixing belt 402 includes a PI or PP substrate, and the glue is made of acrylic material.

[0055] When the fixing belt 402 is bonded and tied, a pre-tightening force of not less than 1N is required to be applied to prevent the fixed connection between the cushion block 401 and the electrode group 3 from failing when the battery is subjected to vibration and impact. However, the pre-tightening force applied by the fixing belt 402 shall not be too large to ensure that the compression amount of the electrode group 3 by the cushion block 401 does not exceed 2mm. In this way, it can ensure that the fixing belt 402 applies an effective pre-tightening force to the cushion block 401 and the electrode group 3, and the cushion block 401 and the electrode group 3 are reliably connected, and the electrode group 3 will not be crushed. The specific pre-tightening force is related to the contact area between the cushion block 401 and the electrode group 3, and can be adjusted according to actual conditions.

[0056] After the pad 401 is fixed on the pole group 3, the pole group 3 is connected to the cover assembly 2, and the pole group 3 connected to the support structure 4 is sealed in the accommodating cavity of the shell 1 through the matching welding between the cover assembly 2 and the shell 1.

[0057] In addition, the binding position of the fixing belt 402 and the cushion block 401 needs to avoid the tabs of the electrode group 3 and the limiting structure of the lower plastic on the electrode group 3.

[0058] Since the pad 401 is adhered and fixed to the pole group 3 by the fixing belt 402, the pad 401 adopts a square structure, which can increase the contact area between the fixing belt 402 and the pole group 3 and the pad 401, and improve the fixing effect of the fixing belt 402 on the pad 401 and the pole group 3.

[0059] In one embodiment, a gap is left between the support structure 4 and the cover plate assembly 2 .

[0060] This arrangement can prevent wear between the support structure 4 and the cover plate assembly 2 caused by battery collision and other factors, thereby preventing the fixing effect between the support structure 4 and the electrode group 3 from being affected.

[0061] In one embodiment, the explosion-proof structure 5 includes at least one explosion-proof valve, which is disposed on the cover plate assembly 2 and communicates with the pressure relief channel.

[0062] When the explosion-proof structure 5 is provided with a plurality of explosion-proof valves, the plurality of explosion-proof valves are arranged at intervals on the cover plate assembly 2 .

[0063] In one embodiment, the cover plate assembly 2 includes a cover plate and a positive pole 6 and a negative pole 6 disposed on the cover plate, and the explosion-proof valve is disposed between the two poles 6 .

[0064] According to an embodiment of the present utility model, on the other hand, a battery pack is provided, comprising a battery according to any one of the above technical solutions.

[0065] Since the battery pack includes batteries and has the same effects as the batteries, they will not be described in detail here.

[0066] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A battery, characterized in that: include: A housing having a receiving cavity and an open end; A cover plate assembly, the cover plate assembly being arranged at the open end of the shell, the cover plate assembly being provided with an explosion-proof structure; A pole group, the pole group is arranged in the accommodating cavity, and a pressure relief channel connected to the explosion-proof structure is provided between the pole group and the cover plate assembly; A support structure is arranged in the pressure relief channel, and the support structure is connected to the pole group.

2. The battery according to claim 1, characterized in that Projected along the direction from the cover plate assembly to the pole group, the projection surface of the support structure at least partially does not overlap with the projection surface of the explosion-proof structure.

3. The battery according to claim 2, characterized in that The supporting structure is arranged on the periphery of the explosion-proof structure.

4. The battery according to claim 2, characterized in that The support structure is located between the explosion-proof structure and the pole group, and at least one dimension of the support structure is larger than a dimension of the explosion-proof structure in the same direction.

5. The battery according to claim 4, characterized in that The support structure is a square structure, and along the width direction of the cover assembly, the width of the support structure is greater than the width of the explosion-proof structure; or, along the length direction of the cover assembly, the length of the support structure is greater than the length of the explosion-proof structure.

6. The battery according to any one of claims 1 to 5, characterized in that The supporting structure comprises a pad, and the thickness of the pad is not less than 3 mm.

7. The battery according to claim 6, characterized in that The cushion block is connected to the pole group via a fixing belt.

8. The battery according to claim 7, characterized in that The fixing tape comprises an adhesive tape or a PP soft tape patch, the middle portion of the fixing tape is adhered to the cushion block, and the remaining portion of the fixing tape is adhered to at least two opposite side surfaces of the pole group.

9. The battery according to claim 1 or 2, characterized in that: A gap is left between the support structure and the cover plate assembly.

10. A battery pack, characterized in that: A battery comprising the battery according to any one of claims 1 to 9.

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