Tab structure and battery

Abstract

The invention relates to the technical field of batteries, and discloses a tab structure and a battery. The insulating part is arranged around the outer surface of the tab body so as to be simultaneously attached to two opposite side surfaces of the tab body along the z direction and two opposite end surfaces of the tab body along the y direction; wherein the side face comprises a flat straight face and connecting faces, the connecting faces are arranged at the two opposite ends of the flat straight face in the y direction, one end of each connecting face is connected with the flat straight face, and the other end of each connecting face is connected with the end face; and the thickness of the tab body at the connecting surface is gradually reduced in the direction from the flat and straight surface to the end surface on the section of the tab body along the y and z directions. The flat and straight surfaces and the end surfaces are connected through the connecting surfaces, so that the positions, close to the two ends, of the tab body are gradually thinned, the insulating parts on the flat and straight surfaces can be gradually guided to the end surfaces through the connecting surfaces, the attaching effect of the insulating parts and the end surfaces is improved, the sealing performance between the insulating parts and the tab body is guaranteed, leakage is avoided, and the service life of the tab body is prolonged. The sealing effect of the battery is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a tab structure and a battery. Background Art

[0002] With the development of the new energy industry, batteries, as the core components of new energy, are also constantly innovating. Soft-pack batteries have the advantages of simple structure and high energy density, and are widely used in the fields of 3C and power batteries. At present, the basic structure of soft-pack batteries is that two pieces of aluminum-plastic film are punched and then put together to seal the battery on the side and top, forming a sealed structure to wrap the battery cell and prevent electrolyte leakage. Usually, before the top seal of the battery is performed, it is necessary to attach an insulating part (such as ear glue) to the periphery of the pole ear, and heat-seal the ear glue with the aluminum-plastic film. However, in the prior art, after the ear glue is attached to the ear, leakage is likely to occur between the ear and the ear glue, affecting the sealing effect of the soft-pack battery. Summary of the invention

[0003] In view of this, the present invention provides a tab structure and a battery to solve the problem in the prior art that after the tab is attached to the tab glue, leakage is likely to occur between the tab and the tab glue, thereby affecting the sealing effect of the battery.

[0004] In a first aspect, the present invention provides a tab structure, comprising: a tab body; an insulating member, arranged around the outer surface of the tab body, so as to simultaneously adhere to two opposite side surfaces of the tab body along the z direction and two opposite end surfaces along the y direction; wherein the side surface comprises a flat surface and a connecting surface, and along the y direction, the connecting surfaces are arranged at both opposite ends of the flat surface, one end of the connecting surface is connected to the flat surface, and the other end of the connecting surface is connected to the end surface; on a cross section of the tab body along the yz direction, the thickness of the tab body at the connecting surface gradually decreases from the flat surface to the end surface, and the thickness of the tab body at the flat surface is T, and the thickness of the tab body at the end surface is T1, satisfying 0.1mm≤T1≤0.5T.

[0005] Beneficial effect: The straight surface and the end surface are connected by the connecting surface, so that the tab body is gradually thinned near the two ends, so that the insulating member on the straight surface can be gradually guided to the end surface by the connecting surface, thereby improving the fitting effect between the insulating member and the end surface, ensuring the sealing between the insulating member and the tab body, avoiding leakage, and improving the sealing effect of the battery. In addition, by limiting the proportional relationship between the thickness of the tab body at the straight surface and the thickness at the end surface, the structural strength of the tab body is ensured while ensuring the tight connection between the insulating member and the tab body.

[0006] In an optional implementation, the connecting surface is an inclined surface.

[0007] Beneficial effect: The connection surface is set as an inclined surface, which facilitates the processing of the tab body and ensures production efficiency.

[0008] In an optional embodiment, in the cross section of the tab body along the yz direction, the angle between the connecting surface and the end surface is α, which satisfies 5°≤α≤85°.

[0009] Beneficial effect: While ensuring that the insulating member is tightly connected to the tab body, the tab body can be easily processed and formed and the structural strength of the tab body can be ensured.

[0010] In an optional embodiment, the thickness T of the tab body at the flat surface satisfies 0.3 mm ≤ T ≤ 2 mm.

[0011] Beneficial effect: while ensuring the structural strength of the tab body to avoid folding and breaking, the tab body can be easily folded to facilitate battery module assembly.

[0012] In an optional implementation, the connecting surface is an arc surface.

[0013] Beneficial effect: The connection surface is set as an arc surface, which facilitates the processing of the tab body and ensures production efficiency.

[0014] In an optional embodiment, the thickness T of the tab body at the flat surface satisfies 0.4 mm ≤ T ≤ 2 mm.

[0015] Beneficial effect: while ensuring the structural strength of the tab body to avoid folding and breaking, the tab body can be easily folded to facilitate battery module assembly.

[0016] In an optional embodiment, in the cross section of the tab body along the yz direction, the radius of the arc surface is r, satisfying 0.2mm≤r≤0.5T.

[0017] Beneficial effect: While ensuring that the insulating member is tightly connected to the tab body, the tab body can be easily processed and formed and the structural strength of the tab body can be ensured.

[0018] In an optional implementation, along the x direction, the width of the insulating member is A, satisfying 5 mm ≤ A ≤ 30 mm.

[0019] Beneficial effect: While ensuring the heat sealing effect between the insulating part and the packaging film, it avoids affecting the overall length design of the battery and ensures the volume energy density of the battery.

[0020] In an optional embodiment, the tab body is suitable for connecting to a pole group, and along the x direction, the tab body has a first side edge close to the pole group and a second side edge away from the pole group;

[0021] Along the x direction, the distance between the side of the insulating member close to the first side edge and the first side edge is E, and E≥5mm; and / or,

[0022] Along the x direction, the distance between one side of the insulating member close to the second side edge and the second side edge is D, and D≥8mm; and / or,

[0023] Along the x direction, a distance C between a side of the insulating member close to the first side edge and a side of the end surface close to the first side edge satisfies 2mm≤C≤20mm; and / or,

[0024] Along the x direction, a distance B between a side of the insulating member close to the second side edge and a side of the end surface close to the second side edge satisfies 2 mm ≤ B ≤ 50 mm.

[0025] Beneficial effect: Make E≥5mm, which is convenient for welding the tab body and the tab of the pole group;

[0026] Make D ≥ 8mm to facilitate welding of the tab body and the busbar when the battery is grouped;

[0027] Make 2mm≤C≤20mm, while ensuring the tight connection between the insulating part and the tab body, avoid affecting the overall length design of the battery, and ensure the volume energy density of the battery;

[0028] Make 2mm≤B≤50mm, while ensuring the tight connection between the insulating part and the tab body, avoid affecting the overall length design of the battery, and ensure the volume energy density of the battery.

[0029] In a second aspect, the present invention further provides a battery, comprising the above-mentioned tab structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the specific implementation methods of the present invention 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 present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 A front view of a tab structure according to an embodiment of the present invention;

[0032] Figure 2 for Figure 1 A partial cross-sectional view of a tab structure along the FF direction is shown;

[0033] Figure 3 for Figure 1A partial cross-sectional view of another type of tab structure along the FF direction is shown;

[0034] Figure 4 It is a front view of a battery according to an embodiment of the present invention.

[0035] Description of reference numerals:

[0036] 1. Tab body; 11. Side surface; 111. Flat surface; 112. Connecting surface; 12. End surface; 13. First side edge; 14. Second side edge; 2. Insulating member; 3. Pole group; 4. Packaging film; 5. Heat sealing area. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0038] Combine the following Figures 1 to 4 , describing an embodiment of the present invention.

[0039] According to an embodiment of the present invention, on the one hand, a tab structure is provided, comprising: a tab body 1; an insulating member 2, which is arranged around the outer surface of the tab body 1 to simultaneously adhere to two opposite side surfaces 11 along the z direction and two opposite end surfaces 12 along the y direction of the tab body 1. The side surface 11 comprises a flat surface 111 and a connecting surface 112, and along the y direction, the opposite ends of the flat surface 111 are provided with connecting surfaces 112, one end of the connecting surface 112 is connected to the flat surface 111, and the other end of the connecting surface 112 is connected to the end surface 12; in the cross section of the tab body 1 along the yz direction, the thickness of the tab body 1 at the connecting surface 112 gradually decreases from the flat surface 111 to the end surface 12.

[0040] The flat surface 111 and the end surface 12 are connected by using the connecting surface 112 so that the tab body 1 gradually becomes thinner near the two ends. Thus, the insulating member 2 on the flat surface 111 can be gradually guided to the end surface 12 by using the connecting surface 112, thereby improving the fitting effect between the insulating member 2 and the end surface 12, ensuring the sealing between the insulating member 2 and the tab body 1, avoiding leakage, and improving the sealing effect of the battery.

[0041] It is worth noting that in the related art, the flat surface 111 is directly connected to the end surface 12, so the insulating member 2 on the flat surface 111 is directly attached to the end surface 12 after being bent at a right angle. The insulating member 2 is prone to not fit tightly with the tab body 1 near the bend, resulting in a gap. The sealing between the insulating member 2 and the tab body 1 is poor, which easily causes leakage between the insulating member 2 and the tab body 1, affecting the sealing effect of the battery. In this embodiment, a transition connection is made between the flat surface 111 and the end surface 12 through the connecting surface 112, which can guide the attachment of the insulating member 2, thereby improving the sealing between the insulating member 2 and the tab body 1.

[0042] Please note that Figure 1 The “direction from the flat surface 111 to the end surface 12 ” refers to the direction from the middle of the tab body 1 to both ends along the y direction.

[0043] Further, in one embodiment, if Figure 2 and Figure 3 As shown, the thickness of the tab body 1 at the flat surface 111 is T, and the thickness of the tab body 1 at the end surface 12 is T1, which satisfies 0.1 mm ≤ T1 ≤ 0.5 T. By limiting the proportional relationship between the thickness of the tab body 1 at the flat surface 111 and the thickness at the end surface 12, the structural strength of the tab body 1 is ensured while ensuring that the insulating member 2 is tightly connected to the tab body 1.

[0044] It should be noted that if T1>0.5T, the thinning degree of the tab body 1 through the connecting surface 112 is too small, the degree of improvement on the connection tightness between the insulating part 2 and the tab body 1 is small, and there is still a risk of leakage between the insulating part 2 and the tab body 1; if T1<0.1mm, the structural strength of the tab body 1 at the corresponding position of the connecting surface 112 is low, and the tab body 1 is easily broken when the tab body 1 is folded during battery group assembly, affecting the production quality and current carrying capacity of the battery module.

[0045] Two implementations of the connection surface 112 are introduced below.

[0046] In a first embodiment of the connection surface 112, as Figure 2 As shown, the connecting surface 112 is an inclined surface. Setting the connecting surface 112 as an inclined surface facilitates processing of the tab body 1 and ensures production efficiency.

[0047] In a first embodiment, if Figure 2As shown, in the cross section of the tab body 1 along the yz direction, the angle between the connection surface 112 and the end surface 12 is α, which satisfies 5°≤α≤85°. This arrangement ensures that the insulating member 2 is tightly connected to the tab body 1, facilitates the processing and forming of the tab body 1, and ensures the structural strength of the tab body 1.

[0048] It is worth noting that if α>85°, the thinning degree of the tab body 1 through the inclined surface is too small, the degree of improvement on the connection tightness between the insulating part 2 and the tab body 1 is small, and there is still a risk of leakage between the insulating part 2 and the tab body 1; if α<5°, the thinning degree of the tab body 1 through the inclined surface is too large, and the structural strength of the tab body 1 at the corresponding position of the connecting surface 112 is low. When the tab body 1 is folded during the battery group assembly, it is easy to cause the tab body 1 to break, affecting the production quality and current carrying capacity of the battery module, and it is not convenient for the processing and forming of the connecting surface 112.

[0049] In a first embodiment, if Figure 2 As shown, the thickness T of the tab body 1 at the flat surface 111 satisfies 0.3mm≤T≤2mm. This arrangement ensures the structural strength of the tab body 1 to avoid folding and breaking, and facilitates the folding of the tab body 1 for easy assembly of the battery module.

[0050] It is worth noting that if T>2mm, the thickness of the tab body 1 is too large, which makes it inconvenient to fold the tab body 1 when the battery is assembled into groups, affecting the processing efficiency and increasing the consumables of the tab body 1, resulting in increased production costs; if T<0.3mm, the thickness of the tab body 1 is too small, resulting in a low structural strength of the tab body 1, which can easily cause the tab body 1 to break when the tab body 1 is folded when the battery is assembled into groups, resulting in increased production costs and delays in production progress.

[0051] The application of the tab structure of the first embodiment with different sizes is described below, and the application results of each embodiment and comparative example are shown in Table 1. The embodiment refers to the tab structure that meets the requirements of the first embodiment, and the comparative example refers to the tab structure that does not meet the requirements of the first embodiment.

[0052] Table 1 Application results of the first embodiment of the tab structure

[0053]

[0054] It can be seen from Table 1 that in Examples 1 to 15, the value of α satisfies 5°≤α≤85°, the value of T satisfies 0.3mm≤T≤2mm, and the value of T1 satisfies 0.1mm≤T1≤0.5T. Therefore, after the insulating member 2 and the tab body 1 are thermally cured, the air tightness test is qualified, and there is good sealing between the insulating member 2 and the tab body 1. Moreover, the tab body is bent 90° 5 times without cracks or breakage, and the tab body 1 has good structural strength.

[0055] It can be seen from Table 1 that in Comparative Example 1, the value of α is greater than 85°, and the value of T1 is greater than 0.5T, resulting in too little thinning of the tab body 1 through the inclined surface. When the insulating component 2 and the tab body 1 are thermally cured, the air tightness test fails, and there is a risk of leakage between the insulating component 2 and the tab body 1.

[0056] It can be seen from Table 1 that in Comparative Example 2, the value of T1 is greater than 0.5T, resulting in too little thinning of the tab body 1 through the inclined surface. When the insulating component 2 and the tab body 1 are thermally cured, the air tightness test fails, and there is a risk of leakage between the insulating component 2 and the tab body 1.

[0057] It can be seen from Table 1 that in Comparative Example 3, the value of α is less than 5°, the value of T1 is less than 0.1 mm, and the tab body 1 is difficult to form during processing, so it is not recommended for use.

[0058] It can be seen from Table 1 that in Comparative Example 4, the value of T is less than 0.3 mm, resulting in the tab body being bent 90° 5 times, cracks appearing on the edge, and the structural strength of the tab body 1 is low.

[0059] It can be seen from Table 1 that in Comparative Example 5, the value of T is greater than 2 mm, which makes it difficult to bend the tab body 90°, making it inconvenient to assemble the battery group, and is not recommended for use.

[0060] In a second embodiment of the connection surface 112, as Figure 3 As shown, the connection surface 112 is an arc surface. Setting the connection surface 112 as an arc surface facilitates processing of the tab body 1 and ensures production efficiency.

[0061] In a second embodiment, if Figure 3 As shown, the thickness T of the tab body 1 at the flat surface 111 satisfies 0.4 mm ≤ T ≤ 2 mm. This arrangement ensures the structural strength of the tab body 1 to prevent folding and breaking, and facilitates the folding of the tab body 1 for easy assembly of the battery module.

[0062] It is worth noting that if T>2mm, the thickness of the tab body 1 is too large, which makes it inconvenient to fold the tab body 1 when the battery is assembled into groups, affecting the processing efficiency and increasing the consumables of the tab body 1, resulting in increased production costs; if T<0.4mm, the thickness of the tab body 1 is too small, resulting in a low structural strength of the tab body 1, which can easily cause the tab body 1 to break when the tab body 1 is folded when the battery is assembled into groups, resulting in increased production costs and delays in production progress.

[0063] In a second embodiment, if Figure 3 As shown, the radius of the arc surface of the tab body 1 in the cross section along the yz direction is r, satisfying 0.2mm≤r≤0.5T. This arrangement ensures that the insulating member 2 is tightly connected to the tab body 1, facilitates the processing and forming of the tab body 1, and ensures the structural strength of the tab body 1.

[0064] It is worth noting that if r>0.5T, the thinning degree of the tab body 1 through the arc surface is too large, and the structural strength of the tab body 1 at the corresponding position of the connecting surface 112 is low. When the tab body 1 is folded during battery group assembly, it is easy to cause the tab body 1 to break, affecting the production quality and current carrying capacity of the battery module, and it is not convenient for the processing and forming of the connecting surface 112; if r<0.2mm, the thinning degree of the tab body 1 through the arc surface is too small, and the degree of improvement of the connection tightness between the insulating part 2 and the tab body 1 is small, and there is still a risk of leakage between the insulating part 2 and the tab body 1.

[0065] The application of the second embodiment of the lug structure of different sizes is described below, and the application results of each embodiment and comparative example are shown in Table 2. The embodiment refers to the lug structure that meets the requirements of the second embodiment, and the comparative example refers to the lug structure that does not meet the requirements of the second embodiment.

[0066] Table 2 Application results of the second embodiment of the tab structure

[0067]

[0068]

[0069] It can be seen from Table 2 that in Examples 16 to 26, the value of r satisfies 0.2mm≤r≤0.5T, and the value of T satisfies 0.4mm≤T≤2mm. Therefore, after the insulating member 2 and the tab body 1 are thermally cured, the airtightness test is qualified, and there is good sealing between the insulating member 2 and the tab body 1. Moreover, the tab body is bent 90° 5 times without cracks or breakage, and the tab body 1 has good structural strength.

[0070] It can be seen from Table 2 that in Comparative Example 6, the value of r is less than 0.1 mm, resulting in too little thinning of the tab body 1 through the inclined surface. When the insulating component 2 and the tab body 1 are thermally cured, the air tightness test fails, and there is a risk of leakage between the insulating component 2 and the tab body 1.

[0071] It can be seen from Table 2 that in Comparative Example 7, the value of r is greater than 0.5T, and the tab body 1 is difficult to form during processing, so it is not recommended for use.

[0072] It can be seen from Table 2 that in Comparative Example 8, the value of T is greater than 2 mm, which makes it difficult to bend the tab body 90°, making it inconvenient to assemble the battery group, and is not recommended for use.

[0073] In one embodiment, Figure 1 As shown, along the x direction, the width of the insulating member 2 is A, which satisfies 5mm≤A≤30mm. This arrangement ensures the heat sealing effect between the insulating member 2 and the packaging film 4 while avoiding affecting the overall length design of the battery and ensuring the volume energy density of the battery.

[0074] It is worth noting that if A>30mm, the area occupied by the insulating part 2 on the tab body 1 is too large, which will affect the welding of the tab body 1 with the tabs and / or busbars of the pole group 3. If sufficient welding area is required, the length of the tab body 1 will be too large, resulting in the overall length of the battery being too large, affecting the volume energy density of the battery, and increasing the consumables of the tab body 1, resulting in increased production costs; if A<5mm, the width of the insulating part 2 is too small, and the heat sealing area between the insulating part 2 and the packaging film 4 is too small, resulting in poor heat sealing firmness, affecting the heat sealing effect of the insulating part 2 and the packaging film 4, and easily causing the battery to leak between the insulating part 2 and the packaging film 4.

[0075] In one embodiment, Figure 1 As shown, the tab body 1 is suitable for connecting to the pole group 3 . Along the x direction, the tab body 1 has a first side edge 13 close to the pole group 3 and a second side edge 14 away from the pole group 3 .

[0076] Further, such as Figure 1 As shown, along the x direction, the distance between the side of the insulating member 2 close to the first side edge 13 and the first side edge 13 is E, and E≥5mm is satisfied. This arrangement facilitates welding of the tab body 1 and the tab of the pole group 3.

[0077] It is worth noting that the tab body 1 is welded to the tab of the pole group 3 through the portion between the insulating member 2 and the first side edge 13. Therefore, if E<5mm, the portion available for welding to the tab of the pole group 3 is too small, which is not convenient for the electrical connection between the tab body 1 and the pole group 3.

[0078] Further, such as Figure 1 As shown, along the x direction, the distance between the side of the insulating member 2 close to the second side edge 14 and the second side edge 14 is D, and D≥8mm. This arrangement facilitates welding of the tab body 1 and the busbar when the batteries are grouped.

[0079] It is worth noting that the tab body 1 is welded to the busbar through the portion between the insulating member 2 and the second side edge 14. Therefore, if D < 8 mm, the portion available for welding to the busbar is too small, which is not convenient for electrical connection between the tab body 1 and the busbar.

[0080] Further, such as Figure 1 As shown, along the x direction, the distance between the side of the insulating member 2 close to the first side edge 13 and the side of the end surface 12 close to the first side edge 13 is C, which satisfies 2mm≤C≤20mm. In this way, while ensuring that the insulating member 2 is tightly connected to the tab body 1, it avoids affecting the overall length design of the battery and ensures the volume energy density of the battery.

[0081] It is worth noting that if C>20mm, the length of the tab body 1 will be too large, resulting in the overall length of the battery being too large, affecting the volume energy density of the battery, and increasing the consumables of the tab body 1, resulting in increased production costs; if C<2mm, the edge of the insulating part 2 is too close to the edge of the end face 12, and the stability of the insulating part 2 wrapped on the end face 12 is poor, which can easily cause the insulating part 2 to separate from the tab body 1, causing a gap between the insulating part 2 and the tab body 1, affecting the sealing between the insulating part 2 and the tab body 1, and there is still a risk of battery leakage between the insulating part 2 and the tab body 1.

[0082] Further, such as Figure 1 As shown, along the x direction, the distance between the side of the insulating member 2 close to the second side edge 14 and the side of the end surface 12 close to the second side edge 14 is B, which satisfies 2mm≤B≤50mm. In this way, while ensuring that the insulating member 2 is tightly connected to the tab body 1, it avoids affecting the overall length design of the battery and ensures the volume energy density of the battery.

[0083] It is worth noting that if B>50mm, the length of the tab body 1 will be too large, resulting in the overall length of the battery being too large, affecting the volume energy density of the battery, and increasing the consumables of the tab body 1, resulting in increased production costs; if B<2mm, the edge of the insulating part 2 is too close to the edge of the end face 12, and the stability of the insulating part 2 wrapped on the end face 12 is poor, which can easily cause the insulating part 2 to separate from the tab body 1, causing a gap between the insulating part 2 and the tab body 1, affecting the sealing between the insulating part 2 and the tab body 1, and there is still a risk of battery leakage between the insulating part 2 and the tab body 1.

[0084] The application of tab structures of different sizes is described below, and the application results of various embodiments and comparative examples are shown in Table 3. The embodiments refer to tab structures that meet the requirements of the embodiments, and correspondingly, the comparative examples refer to tab structures that do not meet the requirements of the embodiments.

[0085] Table 3 Application results of different sizes of tab structures

[0086]

[0087] It can be seen from Table 3 that in Examples 27 to 36, the value of A satisfies 5mm≤A≤30mm, the value of C satisfies 2mm≤C≤20mm, the value of B satisfies 2mm≤B≤50mm, the value of D satisfies D≥8mm, and the value of E satisfies E≥5mm. Therefore, the batteries formed by the assembly of the tab structures of Examples 27 to 36 pass the airtightness test after the battery is pressurized at 0.9MPa inside and maintained for 1min. In addition, there is no abnormality in the tab welding process between the tab body 1 and the pole group 3, and there is no abnormality in the welding with the busbar during the battery group assembly process.

[0088] It can be seen from Table 3 that in Comparative Example 9, the value of A is less than 5 mm, resulting in poor heat sealing effect between the insulating part 2 and the packaging film 4. After the battery is pressurized at 0.9 MPa and maintained at this pressure for 1 minute, the air tightness test fails and the battery leaks between the insulating part 2 and the packaging film 4.

[0089] It can be seen from Table 3 that in Comparative Example 10, the value of C is less than 2 mm, and after the insulating member 2 and the tab body 1 are thermally cured, the insulating member 2 and the tab body 1 are separated, and after the insulating member 2 and the tab body 1 are thermally cured, the air tightness test fails.

[0090] It can be seen from Table 3 that in Comparative Example 11, the value of B is less than 2 mm. After the insulating member 2 and the tab body 1 are thermally cured, the insulating member 2 and the tab body 1 are separated. After the insulating member 2 and the tab body 1 are thermally cured, the air tightness test fails.

[0091] It can be seen from Table 3 that in Comparative Example 12, the value of D is less than 8 mm. During the battery group assembly process, the portion of the tab body 1 that can be used for welding with the busbar is too small, which is not convenient for electrical connection between the tab body 1 and the busbar.

[0092] It can be seen from Table 3 that in Comparative Example 13, the value of E is less than 5 mm. During the battery assembly process, the portion of the tab body 1 that can be used for welding with the tab of the electrode group 3 is too small, which is not convenient for electrical connection between the tab body 1 and the electrode group 3.

[0093] It can be seen from Table 3 that in Comparative Example 14, the value of A is greater than 30 mm. When the values ​​of D and E meet the requirements, the value of A is too large, resulting in the length of the tab body 1 being too large, and the overall length of the battery being too large, affecting the volume energy density of the battery, and increasing the consumables of the tab body 1, resulting in increased production costs. Therefore, it is not recommended for use.

[0094] It can be seen from Table 3 that in Comparative Example 15, the value of C is greater than 20 mm and the value of B is greater than 50 mm, which results in the length of the tab body 1 being too large, resulting in the overall length of the battery being too large, affecting the volume energy density of the battery, and increasing the consumables of the tab body 1, resulting in increased production costs, and is not recommended for use.

[0095] According to an embodiment of the present invention, on the other hand, a battery is provided, comprising the above-mentioned tab structure.

[0096] In one embodiment, the battery further includes: a packaging film 4 having an accommodation space therein; and a pole group 3 disposed in the accommodation space. A first side of the pole tab body 1 is electrically connected to the pole group 3, and the other side of the pole tab body 1 extends in a direction away from the pole group 3 and extends out of the packaging film 4. The packaging film 4 is hot-melted and packaged at an edge of one side where the pole tab body 1 is disposed to form a heat-sealed area 5, and the packaging film 4 and the insulating member 2 are connected and disposed via the heat-sealed area 5.

[0097] It is worth noting that, in this embodiment, the packaging film 4 is an aluminum-plastic film.

[0098] It is worth noting that, in this embodiment, the battery is a soft-pack battery.

[0099] Although the embodiments of the present invention have been 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 tab structure, characterized in that: include: Ji Er body; An insulating member is disposed around the outer surface of the tab body so as to be attached to two opposite side surfaces of the tab body along the z direction and two opposite end surfaces along the y direction at the same time; Wherein, the side surface includes a flat surface and a connecting surface, and the connecting surfaces are provided at the opposite ends of the flat surface along the y direction, one end of the connecting surface is connected to the flat surface, and the other end of the connecting surface is connected to the end surface; in the cross section of the pole ear body along the yz direction, the thickness of the pole ear body at the connecting surface gradually decreases from the flat surface to the end surface, and the thickness of the pole ear body at the flat surface is T, and the thickness of the pole ear body at the end surface is T1, satisfying 0.1mm≤T1≤0.5T.

2. The tab structure according to claim 1, characterized in that: The connecting surface is an inclined surface.

3. The tab structure according to claim 2, characterized in that: In the cross section of the tab body along the yz direction, the angle between the connecting surface and the end surface is α, which satisfies 5°≤α≤85°.

4. The tab structure according to claim 2, characterized in that: The thickness T of the tab body at the flat surface satisfies 0.3 mm ≤ T ≤ 2 mm.

5. The tab structure according to claim 1, characterized in that: The connecting surface is an arc surface.

6. The tab structure according to claim 5, characterized in that: The thickness T of the tab body at the flat surface satisfies 0.4 mm ≤ T ≤ 2 mm.

7. The tab structure according to claim 5, characterized in that: In the cross section of the tab body along the yz direction, the radius of the arc surface is r, satisfying 0.2mm≤r≤0.5T.

8. The electrode ear structure according to any one of claims 1 to 7, characterized in that: Along the x direction, the width of the insulating member is A, satisfying 5 mm ≤ A ≤ 30 mm.

9. The electrode ear structure according to any one of claims 1 to 7, characterized in that: The pole lug body is suitable for connecting to the pole group, and along the x direction, the pole lug body has a first side edge close to the pole group and a second side edge away from the pole group; Along the x direction, the distance between the side of the insulating member close to the first side edge and the first side edge is E, and E≥5mm; and / or, Along the x direction, the distance between one side of the insulating member close to the second side edge and the second side edge is D, and D≥8mm; and / or, Along the x direction, a distance C between a side of the insulating member close to the first side edge and a side of the end surface close to the first side edge satisfies 2mm≤C≤20mm; and / or, Along the x direction, a distance B between a side of the insulating member close to the second side edge and a side of the end surface close to the second side edge satisfies 2 mm ≤ B ≤ 50 mm.

10. A battery, characterized in that: The present invention comprises the electrode ear structure according to any one of claims 1 to 9.

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