Single battery, battery pack and electric equipment
By adopting an insulating tape structure with overlapping bonding parts and avoidance grooves in the battery design, the problem of blue film insulating tape lifting at the four corners of the cell cover plate was solved, thereby improving the stability and safety of the battery.
Patent Information
- Application Number
- CN202423294954.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2026-02-27
- Estimated Expiration
- 2034-12-31
AI Technical Summary
In battery design, as the overall energy density of the battery increases and the size of the terminals increases, the blue film insulating tape is prone to peeling up after wrapping, especially at the four corners of the cell cover, causing production problems.
An insulating tape structure is designed, including a first bonding part and a second insulating part that overlaps with the second bonding part. Combined with a clearance groove design, it ensures the passage of the pole, explosion-proof valve and collection area. PET film and pressure-sensitive adhesive material are used to provide external insulation protection for the battery and reduce the risk of lifting.
It effectively reduces the possibility of insulating tape peeling, improves battery stability and reliability, prevents external substances from entering, and ensures battery safety and normal operation.
Smart Images
Figure CN223956786U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of power batteries, and particularly relates to a single battery cell, a battery pack and an electric device. BACKGROUND
[0002] In order to improve the overall energy density of the battery, the thickness of a single battery cell is gradually reduced, and the width of the top cover also becomes smaller. With the continuous optimization of the overall battery design, in addition to the conventional pole, explosion-proof valve and liquid injection hole, functional areas such as NTC temperature sensing collection area and nickel sheet welding voltage collection area are added to the battery cell cover plate, which results in more and more space occupied on the cover plate. At the same time, with the development of fast charging technology, the pole needs to withstand greater current, so the size of the pole becomes larger and larger. However, since the folding width of the blue film insulation tape to the cover plate is very limited, it is usually only 1.5-2.5mm or even smaller, which results in more and more warping problems after the film is wrapped. Especially in the four corner parts of the battery cell cover plate, due to the large number of layers covered and the small area pasted, the warping problem of the blue film insulation tape is very common in the subsequent manufacturing and assembly process of the battery cell, which brings a lot of trouble to the subsequent production. CONTENT OF THE UTILITY MODEL
[0003] The embodiment of the present application provides a single battery cell, which aims to overcome the more and more warping problems of the insulation tape after the film is wrapped. Another object of the embodiment of the present application is to provide a battery pack. Still another object of the embodiment of the present application is to provide an electric device.
[0004] The embodiment of the present application provides a single battery cell, which comprises:
[0005] A shell having a receiving cavity;
[0006] A pole group arranged in the receiving cavity;
[0007] A cover plate assembly covering the receiving cavity;
[0008] An insulation tape having a first insulation part wrapping the shell and a second insulation part wrapping part of the cover plate assembly, the first insulation part being connected with the second insulation part;
[0009] The second insulation part comprises a first bonding part covering the length direction of the cover plate assembly and a second bonding part covering the width direction of the cover plate assembly, and the second bonding part partially overlaps with the first bonding part.
[0010] In some embodiments, the cover plate assembly comprises a cover plate body and a pole, the cover plate body covers the receiving cavity and is connected with the shell, and the pole penetrates through the cover plate body and is electrically connected with the pole group.
[0011] The second insulation part has a first avoiding slot, and the pole passes through the first avoiding slot.
[0012] In some embodiments, the cover plate assembly further comprises an explosion-proof valve, which is arranged on the cover plate body and connected with the cover plate body.
[0013] The second insulation part has a second avoiding slot, and the explosion-proof valve passes through the second avoiding slot.
[0014] In some embodiments, the cover plate assembly further comprises a collection area, which is arranged on the side of the cover plate body away from the shell.
[0015] The second insulation part has a third avoiding slot, and the third avoiding slot exposes the collection area.
[0016] In some embodiments, the single battery further comprises an insulation patch, which is arranged on the side of the cover plate assembly away from the shell, covers the second insulation part, and is connected with the second insulation part.
[0017] In some embodiments, the overlapping part of the second fitting part and the first fitting part in the width direction of the cover plate assembly has a spacing H, which satisfies 2.2mm≤H≤3.5mm.
[0018] In some embodiments, the first fitting part has a first outer edge, and the spacing between the first outer edge and the outer edge of the cover plate assembly satisfies 3.0mm≤A1≤4.0mm.
[0019] The second fitting part has a second outer edge, and the spacing between the second outer edge and the outer edge of the cover plate assembly satisfies 3.0mm≤A2≤4.0mm, and A1=A2.
[0020] In some embodiments, in the width direction of the cover plate assembly, the spacing between the slot opening of the first avoiding slot and the outer edge of the cover plate assembly satisfies B1≥1.5mm, the spacing between the slot opening of the second avoiding slot and the outer edge of the cover plate assembly satisfies B2≥1.5mm, and the spacing between the slot opening of the third avoiding slot and the outer edge of the cover plate assembly satisfies B3≥1.5mm.
[0021] In the cover plate assembly width direction, the distance L1 between the notch of the first avoiding groove and the side wall of the pole post satisfies 0.2mm≤L1≤0.4mm; the distance L2 between the notch of the second avoiding groove and the side wall of the explosion-proof valve satisfies 0.2mm≤L2≤0.4mm; and the distance L3 between the notch of the third avoiding groove and the outer edge of the collection area satisfies 0.2mm≤L3≤0.4mm.
[0022] The application further discloses a battery pack comprising the single battery.
[0023] The application further discloses a use-electricity device comprising the single battery or the battery pack.
[0024] The application has one of the following beneficial effects:
[0025] The single battery comprises a shell, a pole group, a cover plate assembly and an insulating tape. The shell has a receiving cavity. The pole group is arranged in the receiving cavity. The cover plate assembly seals the receiving cavity. The insulating tape has a first insulating part covering the shell and a second insulating part covering part of the cover plate assembly. The first insulating part and the second insulating part are connected. The first insulating part provides insulation protection at the outside of the battery, i.e. the shell. The second insulating part comprises a first adhering part and a second adhering part. The first adhering part covers the cover plate assembly in the length direction. The second adhering part covers the cover plate assembly in the width direction. The second adhering part and the first adhering part partially overlap. The application realizes the external insulation of the shell of the single battery through the first insulating part, so as to protect the internal structure of the single battery from the external environment. This helps to prevent the intrusion of external substances into the battery and reduces the risk of failure or safety problems of the single battery. On the other hand, the overlapping part of the second adhering part and the first adhering part has only two layers. Compared with the existing structure which needs to be folded and then covered (having three layers), the possibility of warping is reduced. The overlapping part of the second adhering part and the first adhering part has only two layers, and they do not drag each other, so the problem of warping caused by the large number of layers and the integrated structure between the layers in the existing structure can be greatly reduced.
[0026] The battery pack comprises the single battery. Therefore, all the technical features and technical effects of the single battery can be achieved, and details are not repeated here.
[0027] The use-electricity device comprises the single battery or the battery pack. Therefore, all the technical features and technical effects of the single battery or the battery pack can be achieved, and details are not repeated here. BRIEF DESCRIPTION OF DRAWINGS
[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0029] Figure 1 This is a schematic diagram of the exploded structure of a single battery provided in an embodiment of this application;
[0030] Figure 2 This is a schematic diagram of the insulating tape covering position structure provided in the embodiments of this application;
[0031] Figure 3 Provided for the embodiments of this application Figure 2 Enlarged view of a portion of point A in the middle;
[0032] Figure 4 Provided for the embodiments of this application Figure 2 Enlarged view of a section at point C;
[0033] Figure 5 Provided for the embodiments of this application Figure 2 Enlarged view of a section at point B in the middle;
[0034] Figure label:
[0035] 10-Shell;
[0036] 20-pole group;
[0037] 30-Cover plate assembly; 31-Cover plate body; 32-Pole post; 33-Explosion-proof valve; 34-Collection area;
[0038] 40 - Insulating tape; 41 - First insulating part; 42 - Second insulating part; 421 - First bonding part; 4211 - First outer edge; 422 - Second bonding part; 4221 - Second outer edge; 423 - First clearance groove; 424 - Second clearance groove; 425 - Third clearance groove;
[0039] 50 - Insulating patch. Detailed Implementation
[0040] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.
[0041] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In the description of the present application, "a plurality of" means two or more, unless otherwise specified. The association relationship of the associated objects described by "and / or" indicates that there can be three relationships, for example, A and / or B can represent: A exists alone, A and B exist together, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after it. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.
[0042] Those skilled in the art can understand that the drawings are only schematic diagrams of exemplary embodiments and can not be to scale. The modules or flows in the drawings are not necessarily essential for implementing the present application, and therefore cannot be used to limit the scope of protection of the present application.
[0043] As a preliminary part of the embodiments of the present application, lithium ion batteries are widely used in various fields such as transportation power supply, power storage power supply, new energy storage power supply, aerospace and military due to their large capacity, high working voltage, strong charge retention ability, long cycle life and other advantages. A single battery usually includes: a cover plate, a shell, a pole group, a bare cell insulating sheet, a blue film insulating tape, a cover plate top cover patch and other parts. The cover plate and the shell are fixed by welding to form a sealed space with a certain mechanical strength to protect the pole group. The bare cell insulating sheet is wrapped outside the pole group to protect the pole group and prevent the pole group from contacting the shell to cause internal short circuit of the cell. The blue film insulating tape is mainly wrapped on the outside of the shell to achieve external insulation of the cell shell.
[0044] In order to improve the battery package energy density, the thickness of the single battery is getting thinner and thinner, accompanied by the top cover width is getting smaller and smaller; in addition, with the continuous optimization of the whole package design, in addition to the regular pole, explosion-proof valve, liquid injection hole and so on, NTC temperature sensing collection area, nickel sheet welding voltage collection area and so on are also added, which leads to the need to occupy more and more space of the cover plate; at the same time, with the rapid development of fast charging technology, the pole flow demand is increasing, which requires the size of the pole to be larger and larger, so the width of the blue film insulation tape folded to the cover plate is very limited, which is generally 1.5-2.5mm, or even smaller, and then the problem of film lifting after packaging is more and more common, especially in the four corners of the cell cover plate, because the number of layers covered is more and the pasting area is small, the problem of blue film insulation tape lifting is very common in the process of cell post-processing and subsequent grouping, which brings many problems to the subsequent production.
[0045] Therefore, the single battery provided by the embodiments of the present application aims to solve at least part of the above technical problems.
[0046] Please refer to Figure 1 and Figure 2 , Figure 1 the explosion structure schematic diagram of the single battery provided by the embodiments of the present application, Figure 2 the insulation tape covering position structure schematic diagram provided by the embodiments of the present application. The single battery in the embodiments of the present application comprises a shell 10, a pole group 20, a cover plate assembly 30 and an insulation tape 40; wherein the shell 10 has a containing cavity; the pole group 20 is arranged in the containing cavity; the cover plate assembly 30 seals the containing cavity; the insulation tape 40 has a first insulation part 41 covering the shell 10 and a second insulation part 42 covering part of the cover plate assembly 30, the first insulation part 41 is connected with the second insulation part 42, and the first insulation part 41 provides insulation protection at the outside of the battery, i.e. the shell 10. The second insulation part 42 comprises a first bonding part 421 and a second bonding part 422, the first bonding part 421 covers the cover plate assembly 30 in the length direction, the second bonding part 422 covers the cover plate assembly 30 in the width direction, and the second bonding part 422 partially overlaps with the first bonding part 421.
[0047] It should be understood that, in order to better illustrate the structure of the single battery, Figure 1 only part of the shell 10 is shown. The cover plate assembly 30 can be made of aluminum plate material. The cover plate assembly 30 and the shell 10 can be fixedly connected by welding. After the cover plate assembly 30 and the shell 10 are welded, a closed space containing cavity with certain mechanical strength is formed to protect the pole group 20. The insulation tape 40 comprises a PET (polyester) film and a pressure-sensitive adhesive, which is produced by coating the pressure-sensitive adhesive on the PET film. The PET film is a polyester film with good insulation performance. The pressure-sensitive adhesive is an adhesive with adhesion, which is used to fix the PET film on the cover plate assembly 30.
[0048] Therefore, in one aspect, the first insulation part 41 is used to achieve external insulation of the single battery shell 10, thereby protecting the internal structure of the battery from external interference. This helps to prevent the intrusion of external substances into the battery, reducing the risk of battery failure or safety problems. On the other hand, the second bonding part 422 of the second insulation part 42 partially overlaps the first bonding part 421 and has only two layers, which reduces the possibility of warping compared to the existing need to fold and cover (with three layers). Moreover, the overlapping part of the second bonding part 422 and the first bonding part 421 has only two layers, and they do not pull each other, which greatly reduces the problem of warping in the existing structure due to the large number of layers and the integrated structure between the layers, which easily warps due to mutual pulling. Warping refers to the warping phenomenon of the insulation tape 40 during use due to factors such as temperature changes or mechanical stress. By partially overlapping the second bonding part 422 of the second insulation part 42 and the first bonding part 421, the problem of warping at the four corners of the cover plate assembly 30 in the existing structure is overcome, i.e., the risk of warping is reduced, and the stability and reliability of the insulation tape 40 are improved.
[0049] In some embodiments, referring to Figure 3 , Figure 3 the partial enlarged view of A in Figure 2 the embodiment provided by the present application. The cover plate assembly 30 includes a cover plate body 31 and a pole 32. The cover plate body 31 covers the accommodation cavity and is connected to the shell 10. The pole 32 penetrates the cover plate body 31 and is electrically connected to the pole group 20. The second insulation part 42 has a first avoiding slot 423, and the pole 32 is arranged in the first avoiding slot 423.
[0050] It should be understood that the first avoiding slot 423 provides a passage for the pole 32 to pass through the insulation tape 40. In this way, the pole 32 can pass through the insulation tape 40 from the cover plate assembly 30 and be connected to the pole group 20 to realize the conduction and connection of electric current. By arranging the pole 32 in the first avoiding slot 423, the pole 32 can avoid direct contact with the surface of the insulation tape 40. This can reduce the risk of short circuit and ensure the normal operation and safety of the single battery. By using the first avoiding slot 423, reliable connection between the pole 32 and the cover plate assembly 30 and the pole group 20 can be achieved, and necessary insulation protection can be provided to ensure the normal operation and safety of the single battery.
[0051] In some embodiments, referring to Figure 4 , Figure 4 the partial enlarged view of A in Figure 2The local enlarged view at C. The cover plate assembly 30 further comprises an explosion-proof valve 33, which is arranged on and connected with the cover plate body 31; the second insulation part 42 has a second avoiding groove 424, and the explosion-proof valve 33 is arranged in the second avoiding groove 424.
[0052] It should be understood that the explosion-proof valve 33 is mainly used for the directional discharge of high-temperature and high-pressure gas in the single battery when the single battery appears thermal runaway due to internal short circuit, so as to improve the safety performance of the single battery. The second avoiding groove 424 provides a channel for the explosion-proof valve 33, so that it can pass through the insulation tape 40 and be connected with the cover plate assembly 30. The second avoiding groove 424 also provides insulation protection to prevent direct contact between the explosion-proof valve 33 and the insulation tape 40. This helps to prevent current leakage or other safety problems of the single battery during operation.
[0053] In some embodiments, referring to Figure 5 , Figure 5 the above description of the cover plate assembly 30 provided by the embodiments of the present application Figure 2 The local enlarged view at B. The cover plate assembly 30 further comprises a collection area 34, which is arranged on the side of the cover plate body 31 away from the shell 10; the second insulation part 42 has a third avoiding groove 425, and the third avoiding groove 425 exposes the collection area 34.
[0054] It should be understood that the collection area 34 can be used for different types of collection, such as NTC temperature sensing collection area or nickel sheet welding voltage collection area. When it is an NTC temperature sensing collection area: in some embodiments, the collection area 34 can be used to install an NTC (Negative Temperature Coefficient) temperature sensor. The NTC temperature sensing collection area is an area for monitoring the temperature of the single battery. By installing an NTC temperature sensor in the collection area 34, the temperature change of the single battery can be monitored in real time, and the temperature data can be transmitted to the battery management system for temperature control and protection. Another possible type of collection area is an area for welding voltage collection. In this case, the collection area 34 can be used to install nickel sheets connected to the positive and negative electrodes of the single battery. These nickel sheets can be used to measure the voltage of the single battery and transmit the voltage data to the battery management system for voltage monitoring and state estimation. Through the collection area 34, real-time monitoring and collection of parameters such as battery temperature or voltage can be achieved. These data are very important for the safety performance and state estimation of the single battery, which can help the battery management system to carry out accurate control and protection to ensure the normal operation of the single battery and prolong its life. The design of the third avoiding slot 425 makes the collection area 34 exposed, that is, protruding from the surface of the insulating tape 40. In this way, the collection area 34 can be connected with other components (such as sensors, voltage measuring devices, etc.) for data collection and monitoring. The third avoiding slot 425 also provides insulation protection to prevent direct contact between the collection area 34 and the insulating tape 40. This helps to prevent current leakage or other safety problems and ensures the normal operation and reliability of the collection area 34.
[0055] In some embodiments, the single battery further comprises an insulating patch 50 disposed on the side of the cover plate assembly 30 away from the shell 10, covering and connected with the second insulating portion 42.
[0056] It needs to be understood that the insulating patch 50 is made of PC (polycarbonate) material, which has good electrical insulation performance and can effectively cooperate with the insulating tape 40 to realize the insulation of the whole single battery, ensuring the normal operation and safety of the battery. The PC material has high mechanical strength and rigidity, can withstand certain pressure and impact, and can prevent external objects from damaging the internal components of the single battery. The insulating patch 50 made of PC material is combined with glue to realize the connection between the insulating patch 50 and the second insulating part 42. The insulating patch 50 covers the second insulating part 42 and is connected with the second insulating part 42, and cooperates with the insulating tape 40. In this way, it can be ensured that the entire surface of the single battery is covered with insulating material, preventing external environment from interfering with and damaging the battery. That is, the combination of the insulating patch 50 and the insulating tape 40 in the embodiment can realize comprehensive insulation protection of the single battery. This helps to ensure the normal operation and safety of the battery, preventing current leakage, electrical short circuit, mechanical damage and other problems.
[0057] In some embodiments, the distance of the overlapping part of the second bonding part 422 and the first bonding part 421 in the width direction of the cover plate assembly 30 is H, which satisfies 2.2mm≤H≤3.5mm. It needs to be understood that by setting an appropriate distance H, it can be ensured that the overlapping part of the second bonding part 422 and the first bonding part 421 can be firmly connected together. If the distance is too small, it may cause unstable connection and prone to loose or fall off. If the distance is too large, it may cause loose connection, affecting the overall performance of the single battery. The embodiment can ensure that the overlapping part of the second bonding part 422 and the first bonding part 421 can be stably connected, and provide sufficient electrical insulation and mechanical protection effect, by setting the distance of the overlapping part of the second bonding part 422 and the first bonding part 421 in the width direction of the cover plate assembly 30 to satisfy 2.2mm≤H≤3.5mm. This helps to ensure the normal operation of the single battery and improves its performance and reliability.
[0058] In some embodiments, the first bonding part 421 has a first outer edge 42, and the distance between the first outer edge 42 and the outer edge of the cover plate assembly 30 is A1, which satisfies 3.0mm≤A1≤4.0mm; the second bonding part 422 has a second outer edge 4221, and the distance between the second outer edge 4221 and the outer edge of the cover plate assembly 30 is A2, which satisfies 3.0mm≤A2≤4.0mm, A1=A2. It needs to be understood that appropriate distances A1 and A2 can provide mechanical stability to ensure that the connection between the first bonding part 421 and the second bonding part 422 and the cover plate assembly 30 is firm. This helps to prevent loose or fall off of the connection part, improves the durability and reliability of the single battery.
[0059] In some embodiments, in the width direction of the cover plate assembly 30, the distance between the slot of the first avoiding slot 423 and the outer edge of the cover plate assembly 30 is B1, which satisfies B1≥1.5mm; the distance between the slot of the second avoiding slot 424 and the outer edge of the cover plate assembly 30 is B2, which satisfies B2≥1.5mm; and the distance between the slot of the third avoiding slot 425 and the outer edge of the cover plate assembly 30 is B3, which satisfies B3≥1.5mm. In the width direction of the cover plate assembly 30, the distance L1 between the slot of the first avoiding slot 423 and the side wall of the pole 32 satisfies 0.2mm≤L1≤0.4mm; the distance L2 between the slot of the second avoiding slot 424 and the side wall of the explosion-proof valve 33 satisfies 0.2mm≤L2≤0.4mm; and the distance between the slot of the third avoiding slot 425 and the outer edge of the collection area 34 satisfies 0.2mm≤L3≤0.4mm.
[0060] In order to verify the effect of the present application, the insulating adhesive tape 40 sample was prepared according to the above embodiment, and the actual measurement verification was carried out, and the data are as follows:
[0061]
[0062] As shown in the above table, the structure width of the insulating adhesive tape 40 has a greater influence on the wrapping effect, A1 and A2≥3mm, and the relative proportion of the warping problem is relatively small (not more than 0.2%), but any one of B1, B2 and B3 is too small (less than 1.6mm), which will increase the proportion of the warping problem (more than 0.08%, less than 0.2%). In summary, when A1 satisfies 3.0mm≤A1≤4.0mm, A2 satisfies 3.0mm≤A2≤4.0mm, B1 satisfies B1≥1.5mm, B2 satisfies B2≥1.5mm, and B3 satisfies B3≥1.5mm, the proportion of the warping problem of the insulating adhesive tape 40 is small, which can effectively reduce the occurrence probability of the overall warping of the insulating adhesive tape 40 caused by the local warping.
[0063] The embodiment of the present application also discloses a battery pack comprising the single battery as described in the above embodiment. Therefore, all the technical features and technical effects of the single battery described above can be obtained, which will not be described here again.
[0064] The embodiment of the present application also discloses a power consumption device comprising the single battery as described in the above embodiment or comprising the battery pack as described in the above embodiment. Therefore, all the technical features and technical effects of the single battery or the battery pack described above can be obtained, which will not be described here again.
[0065] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.
[0066] The sealing cover provided by the embodiments of the present application is described in detail above, and the principles and implementation manners of the present application are described by using specific examples. The above description of the embodiments is only used to help understand the technical solutions of the present application and the core ideas thereof. It should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features thereof can be replaced equivalently; and the modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A single cell, characterized by, The single battery comprises a shell (10) having a containing cavity, a pole group (20) arranged in the containing cavity, a cover plate assembly (30) covering the containing cavity, an insulation tape (40) having a first insulation part (41) covering the shell (10) and a second insulation part (42) covering part of the cover plate assembly (30), the first insulation part (41) being connected with the second insulation part (42), the second insulation part (42) comprising a first fitting part (421) covering the cover plate assembly (30) in the length direction and a second fitting part (422) covering the cover plate assembly (30) in the width direction, and the second fitting part (422) partially overlapping the first fitting part (421). The cover plate assembly (30) comprises a cover plate body (31) covering the containing cavity and connected with the shell (10) and a pole column (32) penetrating the cover plate body (31) and electrically connected with the pole group (20); The second insulation part (42) has a first avoiding groove (423), and the pole column (32) is arranged in the first avoiding groove (423). The cover plate assembly (30) further comprises an explosion-proof valve (33) arranged on the cover plate body (31) and connected with the cover plate body (31); The second insulation part (42) has a second avoiding groove (424), and the explosion-proof valve (33) is arranged in the second avoiding groove (424). The cover plate assembly (30) further comprises a collection area (34) arranged on the side of the cover plate body (31) away from the shell (10); 2. The unit cell of claim 1, wherein, The second insulation part (42) has a third avoiding groove (425) exposing the collection area (34). The single battery further comprises an insulation patch (50) arranged on the side of the cover plate assembly (30) away from the shell (10), covering the second insulation part (42) and connected with the second insulation part (42).
3. The unit cell of claim 2, wherein, The distance between the overlapping part of the second fitting part (422) and the first fitting part (421) in the width direction of the cover plate assembly (30) is H, and 2.2mm≤H≤3.5mm is satisfied. The first fitting part (421) has a first outer edge (4211), and the distance between the first outer edge (4211) and the outer edge of the cover plate assembly (30) is A1, and 3.0mm≤A1≤4.0mm is satisfied; 4. The unit cell of claim 3, wherein, The second fitting part (422) has a second outer edge (4221), and the distance between the second outer edge (4221) and the outer edge of the cover plate assembly (30) is A2, and 3.0mm≤A2≤4.0mm is satisfied, and A1=A2. 5. The unit cell of any one of claims 1 to 4, wherein, 6. The unit cell of any one of claims 1 to 4, wherein, 7. The cell of claim 1 wherein, 8. The cell of claim 4 wherein, In the width direction of the cover plate assembly (30), the distance between the notch of the first avoiding groove (423) and the outer edge of the cover plate assembly (30) is B1, which satisfies B1≥1.5mm; the distance between the notch of the second avoiding groove (424) and the outer edge of the cover plate assembly (30) is B2, which satisfies B2≥1.5mm; the distance between the notch of the third avoiding groove (425) and the outer edge of the cover plate assembly (30) is B3, which satisfies B3≥1.5mm; In the width direction of the cover plate assembly (30), the distance L1 between the notch of the first avoiding groove (423) and the side wall of the pole (32) satisfies 0.2mm≤L1≤0.4mm; the distance L2 between the notch of the second avoiding groove (424) and the side wall of the explosion-proof valve (33) satisfies 0.2mm≤L2≤0.4mm; the distance L3 between the notch of the third avoiding groove (425) and the outer edge of the collection area (34) satisfies 0.2mm≤L3≤0.4mm.
9. A battery pack, characterized by, A single battery including any one of the single batteries according to any one of claims 1 to 8.
10. An electric device, characterized by A battery pack including any one of the single batteries according to any one of claims 1 to 8, or the battery pack according to claim 9.