Battery cell, battery pack, and electric device

Abstract

The application discloses a battery monomer, a battery pack and a power utilization device. The battery monomer comprises a battery cell, a tab, a current collector and a glue paper. In the length direction of the tab, the tab comprises a bending section and a connecting section connected in sequence, the bending section is connected with the battery cell, and the connecting section is connected with the current collector. The glue paper is bonded to the tab, one side of the glue paper close to the tab is provided with a glue bonding area and a non-glue bonding area, one side of the bending section close to the glue paper is a bending side, at least part of the glue bonding area is bonded to the connecting section, and at least part of the non-glue bonding area is opposite to the bending side. The application aims to reduce the occurrence of tab tearing.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more particularly to a battery cell, a battery pack, and an electrical device. Background Technology

[0002] In related technologies, a single battery cell includes a cell, tabs, current collectors, and adhesive tape.

[0003] Along the length of the electrode, the electrode includes a bent section and a connecting section connected in sequence. The bent section is connected to the battery cell, and the connecting section is connected to the current collector.

[0004] The adhesive tape includes the side of the tab as the bonding side and the side of the bent section near the adhesive tape as the bending side. The bonding side covers the bending side. When the battery cell is sampled for inspection, the tab is pulled by the adhesive tape, which causes the tab to tear. Utility Model Content

[0005] This application provides a battery cell, a battery pack, and an electrical device designed to reduce the occurrence of electrode tab tearing.

[0006] To achieve the above objectives, according to a first aspect of this application, a battery cell is provided, comprising: The battery cell, electrode tab, and current collector are provided. Along the length of the electrode tab, the electrode tab includes a bent section and a connecting section connected in sequence. The bent section is connected to the battery cell, and the connecting section is connected to the current collector. Adhesive tape is attached to the electrode tab. The adhesive tape has an adhesive area and a non-adhesive area on the side near the electrode tab. At least a portion of the adhesive area is attached to the connecting section. The side of the bending section near the adhesive tape is the bending side, and at least a portion of the non-adhesive area is opposite to the bending side.

[0007] In related technologies, the adhesive side of the tape completely covers the bending side of the electrode tab, which means that the tape and the bending side are in a state of "full-area tight adhesion". When the battery cell is sampled for inspection, the tape will inevitably be subjected to external forces. Since the tape is completely adhered to the bending side, these external forces will be directly converted into tearing stress and transmitted to the bending section of the electrode tab through the adhesive side.

[0008] In this disclosure, since at least a portion of the non-adhesive area is opposite the bending side, the bending side is at least partially not bonded by the adhesive tape. This reduces the pulling force of the adhesive tape on the bending section, which helps to reduce the occurrence of tab tearing.

[0009] Optionally, the connecting segment is welded to the current collector to form a solder area, and at least a portion of the adhesive area is located in the solder area.

[0010] In this way, the bonding area between the adhesive area and the soldering area can reduce the amount of debris falling from the soldering area, thereby making the conductivity of the battery cell more stable.

[0011] Optionally, in the length direction of the electrode tab, the length of the electrode tab is L1, the length of the bent side is L2, and 0.1≤L2 / L1≤0.9.

[0012] If the L2 / L1 ratio is too small, the length of the bending section is relatively small compared to the length of the tab. During the manufacturing process of the battery cell, there is not enough operating space for the welding operation between the tab and the current collector. If the L2 / L1 ratio is too large, the length of the connecting section is relatively small compared to the length of the tab, resulting in a smaller solder area and thus reducing the current carrying capacity between the tab and the current collector.

[0013] Therefore, when 0.1≤L2 / L1≤0.9, there is sufficient operating space for welding the tabs and current collectors during the manufacturing process of the battery cell, and the solder area is not too small, resulting in a strong current carrying capacity between the tabs and current collectors.

[0014] Optionally, in the length direction of the tab, the non-adhesive area is located outside the solder area and on the side of the solder area close to the battery cell.

[0015] In this way, the non-adhesive area is located on the side of the solder area closest to the cell, which gives the non-adhesive area a large area opposite the bending area. This makes efficient use of the non-adhesive area and reduces the occurrence of tab tearing.

[0016] Optionally, the area of ​​the region in contact with the non-adhesive area on the bent side is S1, the area of ​​the bent side is S2, K1=S1 / S2, and 0.1≤K1≤1.

[0017] If K1 is smaller, then S1 is smaller than S2. This results in a smaller unbonded area on the bent side, making it easier for the adhesive tape to pull on the bent side when it moves. Consequently, the bent side of the tab is subjected to greater force, making the tab more prone to tearing.

[0018] Therefore, when 0.1 ≤ K1 ≤ 1, the unbonded area on the bent side is larger, making it less likely for the adhesive tape to pull on the bent side during movement. Consequently, the force on the bent side of the tab is smaller, making the tab less prone to tearing. It can be understood that when the bent side is fully in contact with the non-adhesive area, S1 = S2, and K1 = 1.

[0019] Optionally, the thickness of the tab is D micrometers, where 0.1 ≤ D*K1 ≤ 10.

[0020] If K1 is too small, the structural strength of the tab can be increased by increasing D, thereby reducing the risk of the tab tearing. If D is too small, the risk of the tab tearing can be reduced by increasing K1.

[0021] Thus, 0.1≤D*K1≤10 balances K1 and D, reducing the risk of the tab being torn.

[0022] Optionally, in the direction of the solder area near the battery cell, the non-adhesive area extends beyond the bending side.

[0023] In this way, the non-adhesive area can still be opposite the battery cell, which helps to further reduce the tearing of the adhesive paper on the electrode tab when the adhesive paper moves.

[0024] Optionally, in the direction of the solder area near the battery cell, the non-adhesive area does not extend beyond the bending side.

[0025] This results in a larger proportion of the non-adhesive area relative to the bending side, allowing for efficient utilization of the non-adhesive area.

[0026] Optionally, in the length direction of the tab, the length of the bent side is L2, the length of the non-adhesive area is L3, and 0.1≤L3 / L2≤1.

[0027] If L3 / L2 is small, then L3 is relatively smaller than L2. This results in a smaller unbonded area on the bent side, making it easier for the adhesive tape to pull on the bent side when it moves. Consequently, the bent side of the tab is subjected to greater force, making the tab more prone to tearing.

[0028] Therefore, when 0.1 ≤ L3 / L2 ≤ 1, the unbonded area on the bent side is larger, making it less likely for the adhesive tape to pull on the bent side during movement. Consequently, the bent side of the tab experiences less force, making the tab more prone to tearing. It can be understood that when L3 = L2, L3 / L2 = 1.

[0029] Optionally, in the width direction of the tab, the opposite ends of the solder area do not exceed the opposite ends of the non-adhesive area; Thus, along the length of the tab, the edge of the soldering area near the battery cell is covered by the adhesive area, which helps to reduce the force applied to the soldering area near the battery cell when the adhesive paper moves, thereby reducing the occurrence of tearing at the edge of the soldering area near the battery cell.

[0030] Optionally, in the width direction of the tab, the opposite ends of the non-adhesive region do not exceed the opposite sides of the tab.

[0031] In this way, the non-adhesive area will not be too large, and all parts of the non-adhesive area will be fully utilized, which helps to save on the cost of adhesive tape.

[0032] Optionally, the area where the soldering area contacts the adhesive area is a first area, and the area where the soldering area contacts the non-adhesive area is a second area. The first area and the second area are arranged sequentially in the direction of the soldering area near the battery cell.

[0033] Thus, because the connecting section and the current collector are welded relatively firmly, and the boundary between the adhesive and non-adhesive areas is at least partially located in the solder area, the tab can resist tearing by utilizing the connection stability between the connecting section and the current collector. This helps to reduce the occurrence of tab tearing.

[0034] Optionally, the area of ​​the solder mark region is S3, the area of ​​the second region is S4, K2=S4 / S3, and 0.01≤K2<1.

[0035] If K2 is smaller, then S4 is smaller than S3. This makes it easier for the boundary between the adhesive area and the non-adhesive area to be located less in the soldering area, which makes it easier for the adhesive tape to pull the tab when it moves, resulting in greater force on the tab and making the tab easier to tear.

[0036] Therefore, when 0.01≤K2<1, the boundary between the adhesive area and the non-adhesive area is mostly located in the soldering area, which makes it less likely for the adhesive tape to pull the tabs when it moves, thus reducing the force on the tabs and making them less likely to be torn.

[0037] Optionally, the thickness of the tab is D micrometers, where 0.1 ≤ D*K2 ≤ 10.

[0038] If K2 is too small, the structural strength of the tab can be increased by increasing D, thereby reducing the risk of the tab tearing. If D is too small, the risk of the tab tearing can be reduced by increasing K2.

[0039] Thus, 0.1≤D*K2≤10 balances K2 and D, reducing the risk of the tab being torn.

[0040] Optionally, in the length direction of the electrode tab, the length of the second region is L4, 19.9mm ≥ L4 ≥ 0.1mm.

[0041] Thus, the L4 value range is relatively large, which makes the position of the boundary between the adhesive area and the non-adhesive area in the soldering area more flexible, which helps to reduce the manufacturing difficulty of the battery cell.

[0042] Optionally, in the length direction of the tab, the length of the second region is L4, the length of the solder area is L5, and 19.9mm≥L5-L4≥0.1mm.

[0043] Thus, the L5-L4 values ​​have a large range, which makes the location of the boundary between the adhesive area and the non-adhesive area in the soldering area more flexible, which helps to reduce the manufacturing difficulty of the battery cell.

[0044] Optionally, in the width direction of the tab, the opposite ends of the first region do not exceed the opposite ends of the second region.

[0045] Thus, along the length of the tab, the edge of the first region near the battery cell is covered by the second region, which helps to reduce the force applied to the side of the first region near the battery cell when the adhesive tape moves, thereby reducing the occurrence of tearing at the edge of the first region near the battery cell.

[0046] Optionally, in the width direction of the tab, the opposite ends of the non-adhesive region do not exceed the opposite sides of the tab.

[0047] In this way, the non-adhesive area will not be too large, and all parts of the non-adhesive area will be fully utilized, which helps to save on the cost of adhesive tape.

[0048] Optionally, the electrode tab is configured as a positive electrode tab or a negative electrode tab.

[0049] Optionally, the shape of the non-adhesive area can be configured as a rectangle, triangle, ellipse, trapezoid, or square.

[0050] Optionally, at least a portion of the adhesive area is bonded to the battery cell.

[0051] The process of bonding adhesive tape to battery cells and tabs using adhesive-applying equipment is relatively mature, which helps to improve the efficiency of battery cell manufacturing.

[0052] According to a second aspect of this application, a battery pack is provided, including the aforementioned battery cells.

[0053] According to a third aspect of this application, an electrical device is also provided, including the aforementioned battery pack.

[0054] In the battery cell of this application embodiment, since at least a portion of the non-adhesive area is opposite to the bending side, the bending side is not at least partially bonded by adhesive tape. This reduces the pulling force of the adhesive tape on the bending section, which helps to reduce the occurrence of tab tearing.

[0055] Other features and advantages of this application will be described in detail in the following detailed description section. Attached Figure Description 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 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.

[0056] To gain a more complete understanding of this application and its beneficial effects, the following description will be provided in conjunction with the accompanying drawings, wherein the same reference numerals in the following description denote the same parts.

[0057] Figure 1 This is a schematic diagram of the overall structure of the electrical equipment provided in the exemplary embodiments of this disclosure; Figure 2 This is a partial structural diagram of a battery cell during the sampling inspection process provided in an exemplary embodiment of this disclosure; Figure 3 yes Figure 2 Schematic diagram of the structure of medium-strength adhesive paper; Figure 4 yes Figure 2 Schematic diagram of the structure of the battery cell and electrode; Figure 5 This is a schematic diagram of the structure of the adhesive tape connecting the tabs and the cell in one embodiment of a battery cell; Figure 6 yes Figure 5 A schematic diagram of the structure of the middle adhesive paper connecting the electrode tabs; Figure 7 It is replaceable Figure 6 An example of using adhesive tape to connect the electrode tabs; Figure 8 This is a schematic diagram of the structure of the adhesive tape connecting the tabs and the cell in another embodiment of the battery cell; Figure 9 yes Figure 8 A schematic diagram of the structure of the middle adhesive paper connecting the electrode tabs; Figure 10 It is replaceable Figure 9 An example of using adhesive tape to connect the electrode tabs; Figure 11 It is replaceable Figure 9 An example of using adhesive tape to connect the electrode tabs.

[0058] Explanation of reference numerals in the attached figures: 100. Electrical equipment; 200. Battery pack; 300. Battery cell; 400. Battery cell; 500. Tab; 510. Bending section; 511. Bending side; 520. Connecting section; 521. Soldering area; 522. First area; 523. Second area; 600. Current collector; 700. Adhesive tape; 710. Adhesive area; 720. Non-adhesive area. Detailed Implementation

[0059] 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 protection scope of this application.

[0060] Reference Figure 1 and Figure 2 This disclosure provides a battery pack 200. The battery pack 200 is a single physical module comprising multiple battery cells 300 to provide higher voltage and capacity. The battery pack 200 generally includes a battery case for encapsulating the multiple battery cells 300. The battery case can prevent liquids or other foreign matter from affecting the charging or discharging of the battery cells 300.

[0061] The battery cell 300 mentioned in the embodiments of this application may include an electrode assembly and an electrolyte. The electrode assembly includes a positive electrode, a negative electrode, and a separator. The battery cell 300 mainly operates by the movement of metal ions between the positive and negative electrode. The positive electrode includes a positive current collector and a positive active material layer, the positive active material layer being coated on the surface of the positive current collector. The positive current collector includes a positive electrode coating area and a positive electrode tab 500 connected to the positive electrode coating area. The positive electrode coating area is coated with the positive active material layer, while the positive electrode tab 500 is not coated with the positive active material layer. Taking a lithium-ion battery cell 300 as an example, the material of the positive current collector can be aluminum, and the positive active material layer includes a positive active material, which can be lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer, the negative electrode active material layer being coated on the surface of the negative electrode current collector. The negative electrode current collector includes a negative electrode coating area and a negative electrode tab 500 connected to the negative electrode coating area. The negative electrode coating area is coated with the negative electrode active material layer, while the negative electrode tab 500 is not coated with the negative electrode active material layer. The material of the negative electrode current collector can be copper, and the negative electrode active material layer includes negative electrode active material, which can be carbon or silicon, etc. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0062] Currently, the application of battery pack 200 is becoming increasingly widespread. Battery pack 200 is not only used in energy storage power systems such as hydropower, thermal power, wind power, and solar power plants, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, and electric cars, as well as in military equipment and aerospace. With the continuous expansion of battery application areas, the market demand is also constantly increasing.

[0063] The battery described in this application embodiment is used in electrical device 100.

[0064] Electrical equipment 100 can be vehicles, mobile phones, portable devices, laptops, ships, spacecraft, electric toys, and power tools, etc. Vehicles can be gasoline-powered cars, natural gas-powered cars, or new energy vehicles; new energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. Spacecraft include airplanes, rockets, space shuttles, and spacecraft, etc. Electric toys include stationary or mobile electric toys, such as game consoles, electric car toys, electric ship toys, and electric airplane toys, etc. Power tools include metal cutting power tools, grinding power tools, assembly power tools, and railway power tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers, etc. This application embodiment does not impose any special limitations on the above-mentioned electrical equipment 100.

[0065] For ease of explanation, the following embodiments will use a vehicle as an example to illustrate the use of electrical equipment 100.

[0066] The vehicle can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. A battery is installed inside the vehicle, which can be located at the bottom, front, or rear of the vehicle. The battery can be used to power the vehicle; for example, it can serve as the vehicle's operating power source. The vehicle may also include a controller and a motor. The controller is used to control the battery's power supply to the motor, for example, to meet the vehicle's power needs during starting, navigation, and driving.

[0067] It is worth mentioning that, Figure 1 The diagram shows the structure of the electrical equipment 100 when configured as a vehicle. It should be noted that... Figure 1 The battery pack 200 can be seen in the perspective view of the vehicle. The structure shown by the dashed line is the battery pack 200.

[0068] Reference Figures 2 to 6 The battery cell 300 includes a cell 400, a tab 500, a current collector 600, and adhesive tape 700. Along the length of the tab 500, the tab 500 includes a bent section 510 and a connecting section 520 connected in sequence. The bent section 510 is connected to the cell 400, and the connecting section 520 is connected to the current collector 600. The adhesive tape 700 is used to bond the cell 400 and the tab 500. The side of the adhesive tape 700 near the tab 500 has an adhesive area 710 and a non-adhesive area 720. The side of the bent section 510 near the adhesive tape 700 is a bent side 511. At least a portion of the adhesive area 710 is located between the cell 400 and the connecting section 520, and at least a portion of the non-adhesive area 720 is opposite to the bent side 511.

[0069] In the relevant technology, the adhesive side of the adhesive tape 700 completely covers the bending side 511 of the tab 500, which means that the adhesive tape 700 and the bending side 511 are in a state of "full-area tight adhesion". When the battery cell 300 is sampled for inspection, the adhesive tape 700 will inevitably be subjected to external forces. Since the adhesive tape 700 is completely adhered to the bending side 511, these external forces will be directly converted into tearing stress and transmitted to the bending section 510 of the tab 500 through the adhesive side.

[0070] In this disclosure, since at least a portion of the non-adhesive area 720 is opposite to the bending side 511, the bending side 511 is at least partially not bonded by the adhesive tape 700. This reduces the pulling force of the adhesive tape 700 on the bending section 510, which helps to reduce the occurrence of tearing of the tab 500.

[0071] It is worth mentioning that, in one example, the current collector 600 may be configured as a connecting piece, but is not limited to.

[0072] It should be noted that at least part of the non-adhesive region 720 is opposite to the bending side 511, which means that in the normal direction of the non-adhesive region 720, the projection of at least part of the non-adhesive region 720 overlaps with the projection of the bending side 511.

[0073] For ease of explanation, the area of ​​at least part of the non-adhesive region 720 that is opposite to the bending side 511 is referred to as the opposing region. The relationship between the opposing region and the bending side 511 can be as follows: one case is that there is a gap between the opposing region and the bending side 511; another case is that the opposing region is in contact with the bending side 511; yet another case is that a part of the opposing region is in a gap with the bending side 511, while another part of the opposing region is in contact with the bending side 511.

[0074] In some embodiments, the connecting segment 520 is welded to the current collector 600 to form a solder area 521, and at least a portion of the adhesive area 710 is provided in the solder area 521.

[0075] In this way, the bonding area 710 and the soldering area 521 can reduce the amount of debris falling from the soldering area 521, thereby making the conductivity of the battery cell 300 more stable.

[0076] However, this design is not limited to this. In some other embodiments, the connecting segment 520 is riveted to the current collector.

[0077] In some embodiments, the length of the tab 500 is L1 in the longitudinal direction, the length of the bent side 511 is L2, and 0.1≤L2 / L1≤0.9.

[0078] If the L2 / L1 ratio is too small, the length of the bending section 510 is relatively smaller than the length of the tab 500. During the manufacturing process of the battery cell 300, there is not enough operating space for the welding operation between the tab 500 and the current collector 600. If the L2 / L1 ratio is too large, the length of the connecting section 520 is relatively smaller than the length of the tab 500, which makes the solder area 521 smaller, thereby reducing the current carrying capacity between the tab 500 and the current collector 600.

[0079] Therefore, when 0.1≤L2 / L1≤0.9, there is sufficient operating space for the welding operation between the tab 500 and the current collector 600 during the manufacturing process of the battery cell 300, and the solder area 521 is not too small, resulting in a strong current carrying capacity between the tab 500 and the current collector 600.

[0080] In one example, L2 / L1 may be, but is not limited to, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0081] Therefore, in some embodiments, in the length direction of the tab 500, the non-adhesive region 720 is located outside the soldering region 521 and on the side of the soldering region 521 close to the cell 400.

[0082] Thus, the non-adhesive area 720 is entirely located on the side of the solder area 521 closest to the cell 400. This gives the non-adhesive area 720 a large area relative to the bending area, which makes efficient use of the non-adhesive area 720 and reduces the occurrence of tearing of the tab 500.

[0083] In some embodiments, the area of ​​the region where the bent side 511 contacts the non-adhesive region 720 is S1, the area of ​​the bent side 511 is S2, K1=S1 / S2, and 0.1≤K1≤1.

[0084] If K1 is smaller, then S1 is smaller than S2. This makes the unbonded area of ​​the bending side 511 smaller, which makes it easier for the adhesive tape 700 to pull the bending side 511 when it moves. Consequently, the bending side 511 of the tab 500 is subjected to greater force, making the tab 500 easier to tear.

[0085] Therefore, when 0.1 ≤ K1 ≤ 1, the unbonded area of ​​the bending side 511 is larger, making it less likely for the adhesive tape 700 to pull on the bending side 511 during movement. Consequently, the force on the bending side 511 of the tab 500 is smaller, making the tab 500 less prone to tearing. It can be understood that when the bending side 511 is fully in contact with the non-adhesive area 720, S1 = S2, and K1 = 1.

[0086] In one example, K1 may be, but is not limited to, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1.

[0087] In some embodiments, the thickness of the tab 500 is D micrometers, where 0.1 ≤ D * K1 ≤ 10.

[0088] If K1 is too small, the structural strength of tab 500 can be increased by increasing D, thereby reducing the risk of tab 500 tearing. If D is too small, the risk of tab 500 tearing can be reduced by increasing K1.

[0089] Thus, 0.1≤D*K1≤10 balances K1 and D, reducing the risk of the tab 500 being torn.

[0090] In one example, D*K1 can be, but is not limited to, 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0091] Reference Figure 10 In some embodiments, in the direction of the solder area 521 near the cell 400, the non-adhesive area 720 does not extend beyond the bending side 511.

[0092] This results in a larger proportion of the non-adhesive area 720 relative to the bending side 511, allowing for efficient utilization of the non-adhesive area 720.

[0093] However, this design is not limited to this. In some other embodiments, the non-adhesive area 720 extends beyond the bending side 511 in the direction of the solder area 521 near the cell 400. In this way, the non-adhesive area 720 can also be opposite the cell 400, which helps to further reduce the tearing of the adhesive tape 700 on the tab 500 when the adhesive tape 700 moves.

[0094] In some embodiments, in the longitudinal direction of the tab 500, the length of the bent side 511 is L2, the length of the non-adhesive region 720 is L3, and 0.1≤L3 / L2≤1.

[0095] If L3 / L2 is smaller, then L3 is relatively smaller than L2. This makes the unbonded area of ​​the bending side 511 smaller, which makes it easier for the adhesive tape 700 to pull the bending side 511 when it moves. Consequently, the bending side 511 of the tab 500 is subjected to greater force, making the tab 500 easier to tear.

[0096] Therefore, when 0.1≤L3 / L2≤1, the unbonded area of ​​the bending side 511 is larger, making it less likely for the adhesive tape 700 to pull on the bending side 511 during movement. Consequently, the bending side 511 of the tab 500 experiences less force, making the tab 500 more prone to tearing. It can be understood that when L3=L2, L3 / L2=1.

[0097] L3 / L2 can be, but is not limited to, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 or 1.

[0098] It is understandable that the connection section 520 and the current collector 600 are welded relatively firmly. When the battery cell 300 is tested, the adhesive tape 700 will change the position of the tab 500 during its movement. When the deformation of the tab 500 is large, the stress on the side of the solder area 521 near the cell 400 will be greater, and the tab 500 is prone to tearing at the edge of the solder area 521 near the cell 400.

[0099] Therefore, in some embodiments, in the width direction of the tab 500, the opposite ends of the solder area 521 do not exceed the opposite ends of the non-adhesive area 720.

[0100] Thus, along the length of the tab 500, the edge of the soldering area 521 near the cell 400 is covered by the adhesive area 710, which helps to reduce the force applied to the side of the soldering area 521 near the cell 400 when the adhesive tape 700 moves, thereby reducing the occurrence of tearing at the edge of the soldering area 521 near the cell 400.

[0101] In some embodiments, in the width direction of the tab 500, the opposite ends of the non-adhesive region 720 do not exceed the opposite sides of the tab 500.

[0102] In this way, the non-adhesive area 720 will not be too large, and all parts of the non-adhesive area 720 will be fully utilized, which helps to save the cost of the adhesive tape 700.

[0103] It is understandable that when the adhesive tape 700 moves, the stress applied to the tab 500 at the junction of the adhesive area 710 and the non-adhesive area 720 is relatively large, making the tab 500 easy to tear.

[0104] Reference Figure 8 and Figure 9 Therefore, in some embodiments, the area where the solder area 521 contacts the adhesive area 710 is the first area 522, and the area where the solder area 521 contacts the non-adhesive area 720 is the second area 523. The first area 522 and the second area 523 are arranged sequentially in the direction of the solder area 521 near the cell 400.

[0105] Thus, since the connecting section 520 and the current collector 600 are welded relatively firmly, and the boundary between the adhesive area 710 and the non-adhesive area 720 is at least partially located in the solder area 521, the tab 500 can resist tearing by utilizing the connection stability between the connecting section 520 and the current collector 600. This helps to reduce the occurrence of tab 500 tearing.

[0106] In some embodiments, the area of ​​the soldering area 521 is S3, the area of ​​the second area 523 is S4, K2=S4 / S3, and 0.01≤K2<1.

[0107] If K2 is smaller, then S4 is smaller than S3. This makes it easier for the junction between the adhesive area 710 and the non-adhesive area 720 to be less located in the soldering area 521. As a result, when the adhesive tape 700 moves, it is easier to pull the tab 500, which in turn makes the tab 500 subject to greater force and makes the tab 500 easier to tear.

[0108] Therefore, when 0.01≤K2<1, the junction between the adhesive area 710 and the non-adhesive area 720 is mostly located in the soldering area 521, which makes it less likely for the adhesive tape 700 to pull the tab 500 when it moves, thus reducing the force on the tab 500 and making it less likely for the tab 500 to be torn.

[0109] In one example, K2 can be configured, but is not limited to, 0.01, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0110] In some embodiments, the thickness of the tab 500 is D micrometers, where 0.1 ≤ D * K2 ≤ 10.

[0111] If K2 is too small, the structural strength of tab 500 can be increased by increasing D, thereby reducing the risk of tab 500 tearing. If D is too small, the risk of tab 500 tearing can be reduced by increasing K2.

[0112] Thus, 0.1≤D*K2≤10 balances K2 and D, reducing the risk of the tab 500 being torn.

[0113] In one example, D*K2 can be, but is not limited to, 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0114] In some embodiments, the length of the second region 523 in the longitudinal direction of the tab 500 is L4, 19.9mm ≥ L4 ≥ 0.1mm.

[0115] Thus, the L4 value range is relatively large, which makes the position of the junction between the adhesive area 710 and the non-adhesive area 720 in the solder area 521 more flexible, which helps to reduce the manufacturing difficulty of the battery cell 300.

[0116] In one example, L4 may be, but is not limited to, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, or 19.9mm.

[0117] In some embodiments, in the longitudinal direction of the tab 500, the length of the second region 523 is L4, the length of the solder area 521 is L5, and 19.9mm≥L5-L4≥0.1mm.

[0118] Thus, the numerical range of L5-L4 is relatively large, which makes the position of the junction between the adhesive area 710 and the non-adhesive area 720 in the soldering area 521 more flexible, which helps to reduce the manufacturing difficulty of the battery cell 300.

[0119] In one example, L5-L4 may be, but is not limited to, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, or 19.9mm.

[0120] In some embodiments, in the width direction of the tab 500, the opposite ends of the first region 522 do not exceed the opposite ends of the second region 523.

[0121] Thus, along the length of the tab 500, the edge of the first region 522 near the cell 400 is covered by the second region 523, which helps to reduce the force applied to the side of the first region 522 near the cell 400 when the adhesive tape 700 moves, thereby reducing the occurrence of tearing at the edge of the first region 522 near the cell 400.

[0122] In some embodiments, in the width direction of the tab 500, the opposite ends of the non-adhesive region 720 do not exceed the opposite sides of the tab 500.

[0123] In this way, the non-adhesive area 720 will not be too large, and all parts of the non-adhesive area 720 will be fully utilized, which helps to save the cost of the adhesive tape 700.

[0124] There are many possible locations for the bending area side and the solder area 521. In some embodiments, the tab 500 has a first side and a second side in the thickness direction of the tab 500, and the first side or the second side is provided with a bending side 511 and a solder area 521.

[0125] Thus, users can set the bending side 511 and the soldering area 521 on the first or second side according to actual needs. It can be understood that the first and second sides can be the front side of the tab 500, and the other can be the back side of the tab 500.

[0126] The polarity of the tab 500 can be varied. In some embodiments, the tab 500 is configured as a positive tab 500 or a negative tab 500.

[0127] The non-adhesive area 720 has many shapes, see reference. Figure 7 and Figure 11 In some embodiments, the non-adhesive region 720 is configured in the shape of a rectangle, triangle, ellipse, trapezoid, or square. It is worth noting that, for the trapezoid, in one example, the lower base of the trapezoid is positioned close to the battery cell 400, or the upper base of the trapezoid is positioned close to the battery cell 400.

[0128] In some embodiments, the adhesive tape 700 is configured as insulating adhesive tape 700.

[0129] In some embodiments, at least a portion of the adhesive area 710 is bonded to the battery cell 400. The process of bonding the adhesive tape 700 to the battery cell 400 and the tab 500 using an adhesive applicator is relatively mature, which helps to increase the efficiency of manufacturing the battery cell 300. However, this design is not limited to this; in some other embodiments, the adhesive tape 700 may only be adhesively bonded to the tab 500.

[0130] It should be noted that the dimensions of the adhesive tape 700 and the tab 500 are obtained when the adhesive tape 700 is in a flat state. During the process of obtaining the dimensions of the adhesive tape 700 and the tab 500, the length direction of the tab 500 is direction A as shown in the attached figure, and the width direction of the tab 500 is direction B as shown in the attached figure.

[0131] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0132] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0133] The embodiments, implementation methods, and related technical features of this application can be combined and substituted for each other without conflict.

[0134] The above are merely preferred embodiments of this application and are not intended to limit this application in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the scope of the technical solution of this application.

Claims

1. A battery cell, characterized in that, include: The battery cell, electrode, and current collector are provided. In the length direction of the electrode, the electrode includes a bent section and a connecting section connected in sequence. The bent section is connected to the battery cell, and the connecting section is connected to the current collector. as well as Adhesive tape is used to bond the electrode tab. The adhesive tape has an adhesive area and a non-adhesive area on the side near the electrode tab. At least a portion of the adhesive area is bonded to the connecting section. The side of the bending section near the adhesive tape is the bending side, and at least a portion of the non-adhesive area is opposite to the bending side.

2. The battery cell according to claim 1, characterized in that, The connecting section is welded to the current collector to form a solder area, and at least a portion of the adhesive area is located in the solder area.

3. The battery cell according to claim 1, characterized in that, In the length direction of the electrode tab, the length of the electrode tab is L1, the length of the bent side is L2, and 0.1≤L2 / L1≤0.

9.

4. The battery cell according to claim 2, characterized in that, Along the length of the tab, the non-adhesive area is located outside the solder area and on the side of the solder area closer to the battery cell.

5. The battery cell according to claim 4, characterized in that, The area of ​​the region in contact with the non-adhesive area on the bent side is S1, the area of ​​the bent side is S2, K1=S1 / S2, 0.1≤K1≤1.

6. The battery cell according to claim 5, characterized in that, The thickness of the electrode tab is D micrometers, and 0.1≤D*K1≤10.

7. The battery cell according to claim 4, characterized in that, In the direction of the solder area near the battery cell, the non-adhesive area extends beyond the bending side.

8. The battery cell according to claim 4, characterized in that, In the direction of the solder area near the battery cell, the non-adhesive area does not extend beyond the bending side.

9. The battery cell according to claim 8, characterized in that, In the length direction of the electrode tab, the length of the bent side is L2, the length of the non-adhesive area is L3, and 0.1≤L3 / L2≤1.

10. The battery cell according to claim 4, characterized in that, In the width direction of the electrode tab, the opposite ends of the solder area do not exceed the opposite ends of the non-adhesive area; And / or, in the width direction of the tab, the opposite ends of the non-adhesive region do not exceed the opposite sides of the tab.

11. The battery cell according to claim 2, characterized in that, The area where the soldering area contacts the adhesive area is the first area, and the area where the soldering area contacts the non-adhesive area is the second area. The first area and the second area are arranged sequentially in the direction of the soldering area near the battery cell.

12. The battery cell according to claim 11, characterized in that, The area of ​​the solder mark region is S3, the area of ​​the second region is S4, K2=S4 / S3, and 0.01≤K2<1.

13. The battery cell according to claim 12, characterized in that, The thickness of the electrode tab is D micrometers, and 0.1≤D*K2≤10.

14. The battery cell according to claim 11, characterized in that, In the longitudinal direction of the electrode tab, the length of the second region is L4, 19.9mm ≥ L4 ≥ 0.1mm; And / or, in the length direction of the tab, the length of the second region is L4, the length of the solder area is L5, and 19.9mm ≥ L5 - L4 ≥ 0.1mm; And / or, in the width direction of the electrode tab, the opposite ends of the first region do not exceed the opposite ends of the second region; And / or, in the width direction of the tab, the opposite ends of the non-adhesive region do not exceed the opposite sides of the tab.

15. The battery cell according to any one of claims 1 to 14, characterized in that, The electrode tab is configured as a positive electrode tab or a negative electrode tab; And / or, the shape of the non-adhesive area is configured as a rectangle, triangle, ellipse, trapezoid, or square; And / or, at least a portion of the adhesive area is bonded to the battery cell.

16. A battery pack, characterized in that, Includes the battery cell described in any one of claims 1 to 15.

17. An electrical appliance, characterized in that, Includes the battery pack as described in claim 16.

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