Insulating film assembly and battery

Abstract

The invention belongs to the technical field of batteries, and discloses an insulating film assembly and a battery, the insulating film assembly is connected with a pole group, the insulating film assembly comprises an insulating film body and a side plate, the pole group is coated with the insulating film body, and a positioning piece is arranged on one side of the insulating film body; positioning holes are formed in the positions, corresponding to the positioning pieces, of the side plates, and the positioning pieces are clamped in the positioning holes so that the side plates can be connected with the insulating film body. Thus, the positioning piece is arranged on the insulating film body and is clamped with the positioning hole, so that the connection stability between the insulating film body and the side plate can be improved, preliminary positioning of the side plate is facilitated, the step of opening the hole in the insulating film body is omitted, the insulating film body and the side plate can be tightly attached, and the gap between the insulating film body and the side plate is reduced; and the electrolyte is prevented from leaking and corroding the shell and the anti-explosion valve.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to an insulating film assembly and a battery. Background Art

[0002] Batteries are a common energy storage device. Lithium-ion batteries, as power batteries, are widely used in electric vehicles and energy storage fields.

[0003] The battery includes a cell and a shell. In the application of long-cell lithium-ion batteries, an explosion-proof valve is usually set at the bottom of the shell to achieve thermal and electrical separation, thereby improving the safety of the cell. In addition, the outside of the electrode group is wrapped with an electrode group insulation film and side plates for insulation protection.

[0004] However, during the assembly process, the insulating film is provided with holes that engage with the side plates, so that the insulating film and the side plates may not be tightly combined, resulting in a gap between the two, which allows the electrolyte to leak out, connecting the electrode group and the bottom of the shell and causing a short circuit, causing shell corrosion, and the explosion-proof valve notches are relatively weak and easily corroded by the electrolyte, resulting in leakage of liquid and gas, affecting the normal use of the explosion-proof valve. Summary of the invention

[0005] The object of the present invention is to provide an insulating membrane assembly and a battery to solve the problem that the electrolyte easily flows into the shell through the gap between the insulating membrane and the side plate, causing corrosion to the shell and the explosion-proof valve.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, an insulating film assembly is connected to a pole group, the insulating film assembly comprising: an insulating film body, the insulating film body covering the pole group, a positioning piece being provided on one side of the insulating film body; a side plate, the side plate having a positioning hole corresponding to the position of the positioning piece, the positioning piece being clamped in the positioning hole to connect the side plate to the insulating film body.

[0008] Preferably, the side plate is arranged on a side of the insulating film body facing the pole group, or the side plate is arranged on a side of the insulating film body facing away from the pole group.

[0009] Preferably, the positioning member is a positioning convex bump, and the positioning convex bump is integrally formed on the insulating film body.

[0010] Preferably, the height of the positioning convex hump is H1, the thickness of the side plate is H2, and H1≤H2 is satisfied.

[0011] Preferably, two positioning holes are provided, and the two positioning holes are respectively opened at two ends of the side plate, and the positioning convex bumps are arranged in a one-to-one correspondence with the positioning holes.

[0012] Preferably, the distance between the two positioning convex hulls is L1, the width of the insulating film body is L2, and 1 / 3L2 ≤ L1 ≤ L2 - 10 mm is satisfied.

[0013] Preferably, the diameter of the positioning convex hull is D1, the diameter of the positioning hole is D2, and D1 + 0.1 mm ≤ D2 ≤ D1 + 6 mm is satisfied.

[0014] Preferably, the thickness of the side plate is H2, and 0.15 mm ≤ H2 ≤ 2 mm is satisfied; and / or, the thickness of the insulating film body is H3, and 0.1 mm ≤ H3 ≤ 0.3 mm is satisfied.

[0015] In a second aspect, a battery includes a pole group, a housing, and the insulating film assembly as described above, and the insulating film body is disposed between the pole group and the housing.

[0016] Preferably, two positioning holes are provided, an explosion-proof valve is provided on the bottom surface of the housing, and in the thickness direction of the bottom surface of the housing, the projection of the explosion-proof valve is correspondingly disposed between the projections of the two positioning holes.

[0017] Advantages of the present invention:

[0018] An insulating film assembly is connected to a pole group. The insulating film assembly includes an insulating film body and a side plate. The insulating film body is disposed to wrap the pole group, and a positioning member is provided on one side of the insulating film body; a positioning hole is provided in the side plate corresponding to the position of the positioning member, and the positioning member is clamped in the positioning hole so that the side plate is connected to the insulating film body.

[0019] In this way, by providing a positioning member on one side of the insulating film body and a positioning hole on the side plate that cooperates with the positioning member, the connection stability between the insulating film body and the side plate can be improved, the side plate can be accurately positioned to the installation position on the insulating film body, the assembly efficiency can be improved while the step of opening holes in the insulating film body can be saved, the gap between the insulating film body and the side plate can be reduced, and the error generated during the assembly process can be reduced, avoiding the electrolyte from flowing through the gap to contact the housing and the explosion-proof valve and causing corrosion to them, thereby reducing safety hazards such as battery short circuits caused by electrolyte leakage, extending the service life of the housing and the explosion-proof valve, and improving the safety of the battery; the insulating film body and the side plate are connected through the positioning member and the positioning hole, which can limit the relative position between the insulating film body and the side plate and prevent the side plate from shifting during the battery assembly process, affecting the assembly effect. Description of the Drawings

[0020] Figure 1 is a top view of the insulating film assembly in an embodiment of the present invention;

[0021] Figure 2It is a schematic structural diagram after folding of the insulating film body in an embodiment of the present invention;

[0022] Figure 3 It is a partial cross-sectional view of the insulating film assembly in an embodiment of the present invention;

[0023] Figure 4 It is a schematic structural diagram of the insulating film body in an embodiment of the present invention;

[0024] Figure 5 It is a schematic structural diagram of the side plate in an embodiment of the present invention;

[0025] Figure 6 It is a top view of the insulating film body in an embodiment of the present invention;

[0026] Figure 7 It is a top view of the side plate in an embodiment of the present invention.

[0027] In the figure:

[0028] 1. Insulating film body; 11. Positioning member; 2. Side plate; 21. Positioning hole; 22. Material reduction hole. Specific embodiments

[0029] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. Additionally, it should be noted that for the sake of convenience of description, only the parts related to the present invention are shown in the drawings, rather than all the structures.

[0030] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0031] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact of the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "above and over", and "on top of" the second feature includes the first feature being directly above and obliquely above the second feature, or simply indicating that the first feature has a higher horizontal height than the second feature. The first feature being "below", "below and under", and "beneath" the second feature includes the first feature being directly below and obliquely below the second feature, or simply indicating that the first feature has a lower horizontal height than the second feature.

[0032] In the description of this embodiment, the orientation or positional relationships such as "upper", "lower", "right", etc. are based on the orientation or positional relationships shown in the drawings. These are only for the convenience of description and simplifying the operations, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0033] Referring to Figure 1 , the present invention provides an insulating film assembly, which is connected to a pole group (not shown in the figure). The insulating film assembly includes an insulating film body 1 and a side plate 2. The insulating film body 1 is arranged to wrap the pole group. A positioning member 11 is provided on one side of the insulating film body 1; a positioning hole 21 is formed in the side plate 2 at a position corresponding to the positioning member 11, and the positioning member 11 is clamped in the positioning hole 21 so that the side plate 2 is connected to the insulating film body 1.

[0034] In this embodiment, the insulating film body 1 is arranged to wrap the side walls, top surface and bottom surface of the pole group. The length direction of the side plate 2 is parallel to the width direction of the insulating film body 1. The positioning member 11 is arranged in the middle of the insulating film body 1. When the positioning member 11 is clamped in the positioning hole 21, the side plate 2 is located in the middle of the insulating film body 1, and after the insulating film body 1 wraps the pole group, the side plate 2 is located below the pole group.

[0035] In this way, by providing the positioning member 11 on one side of the insulating film body 1 and making it engage with the positioning hole 21 on the side plate 2, the connection stability between the insulating film body 1 and the side plate 2 can be improved, preventing loosening or misalignment between the insulating film body 1 and the side plate 2. Moreover, there is no need to open holes in the insulating film body 1, reducing the gap between the insulating film body 1 and the side plate 2, avoiding the electrolyte from flowing through the gap to contact the housing (not shown in the figure) and corroding the housing and the explosion-proof valve (not shown in the figure), reducing potential safety hazards such as battery short circuits caused by electrolyte leakage, extending the service life of the housing and the explosion-proof valve, and improving the safety of the battery; the engagement of the positioning member 11 with the positioning hole 21 can facilitate the accurate alignment of the positions of the insulating film body 1 and the side plate 2, reducing the errors generated during the assembly process and improving the assembly efficiency.

[0036] It can be understood that the position of the positioning member 11 can be adjusted according to the installation position of the side plate 2, as long as it can achieve the preliminary positioning and limiting of the side plate 2, which will not be elaborated here.

[0037] Referring to Figure 2 and Figure 3, in some embodiments, the side plate 2 is disposed on the side of the insulating film body 1 facing the electrode group. In this embodiment, the length of the side plate 2 is less than the width of the insulating film body 1, that is, both ends of the side plate 2 are spaced from the edge of the insulating film body 1, and the positioning member 11 is disposed on the side of the insulating film body 1 facing the side plate 2.

[0038] In this way, the side plate 2 can support the electrode group and improve the structural strength of the bottom of the electrode group. There are gaps between both ends of the side plate 2 and the edge of the insulating film body 1, which can improve the assembly flexibility to adapt to electrode groups of different sizes. And when there are no openings in the insulating film body 1, the side plate 2 and the insulating film body 1 can be closely attached through the positioning member 11 and the positioning hole 21. This can not only reduce the gap between the side plate 2 and the insulating film body 1, avoid the electrolyte contacting the housing and the explosion-proof valve and corroding the housing and the explosion-proof valve by the electrolyte, but also the side plate 2 can block the leakage of the electrolyte to the housing and the explosion-proof valve, improving the stability and safety of the battery.

[0039] It can be understood that the side plate 2 can also be disposed on the side of the insulating film body 1 facing away from the electrode group to block the direct contact between the electrolyte and the housing. The setting position of the side plate 2 can be adjusted according to actual design requirements as long as the side plate 2 and the insulating film body 1 can be closely attached, and no more examples will be listed here.

[0040] Refer to Figure 4 , in some embodiments, the positioning member 11 is a positioning convex hull, and the positioning convex hull is integrally formed on the insulating film body 1.

[0041] In this embodiment, the positioning convex hull extends in the direction facing the side plate 2, and the cross-sectional area of the positioning convex hull is smaller than the cross-sectional area of the positioning hole 21.

[0042] In this way, the positioning convex hull can be closely attached to the insulating film body 1, enhancing the sealing performance at the connection between the positioning convex hull and the insulating film body 1, and restricting the position of the positioning convex hull on the insulating film body 1, making the assembly process simpler and faster. Since the cross-sectional area of the positioning convex hull is smaller than the cross-sectional area of the positioning hole 21, there is a certain tolerance space when the positioning convex hull is inserted into the positioning hole 21, avoiding the positioning convex hull being stuck too tightly with the positioning hole 21, improving the assembly efficiency, and making the connection between the side plate 2 and the insulating film body 1 more stable, avoiding electrolyte penetration and corrosion of the housing and the explosion-proof valve.

[0043] It can be understood that the positioning member 11 can also be a positioning patch structure, which is attached to the insulating film body 1. In this embodiment, the positioning convex hull is integrally formed with the insulating film body 1 to facilitate the processing of the positioning convex hull, improve the assembly efficiency, facilitate setting the positioning convex hull at the same position when mass-producing the insulating film body 1, improve the consistency of mass production, and reduce the manufacturing cost.

[0044] Refer to Figure 3In some embodiments, the height of the positioning convex bump is H1, the thickness of the side plate 2 is H2, and H1≤H2. That is, when the positioning convex bump is engaged with the positioning hole 21, the end surface of the positioning convex bump facing away from the insulating film body 1 is located inside the positioning hole 21.

[0045] In this embodiment, the side wall of the positioning convex bump is spaced apart from the hole wall of the positioning hole 21 .

[0046] In this way, there can be enough space in the positioning hole 21 for the positioning convex to engage, avoiding assembly difficulties caused by the positioning convex fitting too tightly with the positioning hole 21, improving the connection stability between the side panel 2 and the insulating film body 1 and the structural strength of the connection, avoiding the side panel 2 from shifting or loosening, and at the same time achieving close contact between the side panel 2 and the insulating film body 1, reducing the gap between the side panel 2 and the insulating film body 1, and avoiding the electrolyte from penetrating and corroding the shell and the explosion-proof valve; the positioning convex is recessed in the side panel 2, which can maintain the surface flatness of the side panel 2.

[0047] It can be understood that the height H1 of the positioning bulge cannot be too high, otherwise it will cause the positioning bulge to protrude from the positioning hole 21 and interfere with other structures provided on the side of the side panel 2 away from the insulating film body 1. The height H1 of the positioning bulge cannot be too low, otherwise it will be difficult to engage with the positioning hole 21, causing the side panel 2 to shift.

[0048] See also Figure 4 and Figure 5 In some embodiments, two positioning holes 21 are provided, and the two positioning holes 21 are respectively opened at both ends of the side plate 2, and the positioning convex bumps are provided in a one-to-one correspondence with the positioning holes 21.

[0049] In this embodiment, the positioning holes 21 are arranged through both sides of the side plate 2 in the thickness direction, and the two positioning holes 21 are symmetrically arranged along the symmetry axis in the width direction of the side plate 2 .

[0050] In this way, by setting positioning holes 21 at both ends of the side plate 2 and symmetrically setting the two positioning holes 21, when the positioning piece 11 is engaged with the positioning holes 21, both ends of the side plate 2 can be stably connected to the insulating film body 1, and it is beneficial to quickly assemble the side plate 2 to the insulating film body 1, thereby improving the assembly efficiency, and after the side plate 2 is assembled to the insulating film body 1, the relative position of the side plate 2 and the insulating film body 1 is fixed, thereby avoiding the influence of unilateral offset on the assembly effect; the two ends of the side plate 2 are connected to the insulating film body 1, which can make the force on the two ends of the side plate 2 more uniform, avoid stress concentration causing material fatigue or deformation, improve the stability and sealing of the connection between the side plate 2 and the insulating film body 1, and avoid the electrolyte from corroding the shell and the explosion-proof valve through the gap between the insulating film body 1 and the side plate 2.

[0051] It can be understood that the number of the positioning members 11 and the positioning holes 21 is not limited to two, and can also be four, six, etc., as long as the stable connection between the side plate 2 and the insulating film body 1 can be achieved, and no more examples will be given here.

[0052] Refer to Figure 4 , in some embodiments, the distance between the two positioning protrusions is L1, the width of the insulating film body 1 is L2, and 1 / 3L2 ≤ L1 ≤ L2 - 10 mm is satisfied.

[0053] In this way, by limiting the distance between the two positioning protrusions, it is possible to prevent the side plate 2 from being displaced during the positioning with the insulating film body 1, increase the connection stability between the side plate 2 and the insulating film body 1, and avoid the two ends of the side plate 2 from being easily warped due to the positioning holes 21 being too far away from the side plate 2, improve the assembly quality, and reduce the gap between the side plate 2 and the insulating film body 1 to prevent the electrolyte from corroding the housing and the explosion-proof valve.

[0054] It can be understood that the distance L1 between the two positioning protrusions cannot be too small, otherwise the edge of the insulating film body 1 will wrinkle, affecting the flatness, and the two ends of the side plate 2 will be easily warped. The distance L1 between the two positioning protrusions cannot be too large either, otherwise the middle of the side plate 1 will be easily bulged. The distance L1 between the positioning protrusions can be adjusted according to the width L2 of the insulating film body, and no more details will be described here.

[0055] Refer to Figure 2 , in some embodiments, the positioning protrusions are heat-set on the insulating film body 1, and the insulating film body 1 is connected to the side plate 2 by hot melting.

[0056] In this embodiment, the positioning protrusions face the electrode group. After the side plate 2 and the insulating film body 1 are assembled by the engagement of the positioning protrusions and the positioning holes 21, the unperforated area of the side plate 2 is connected to the insulating film body 1 by hot melting.

[0057] In this way, with the positioning protrusions facing the electrode group, the insulating film body 1 and the side plate 2 can both be closely attached to the electrode group, and the side plate 2 and the insulating film body 1 can be doubly fixed by mechanical engagement and hot-melt sealing. It can not only achieve the preliminary positioning of the side plate 2 on the insulating film body 1 through the positioning protrusions and the positioning holes 21, facilitating subsequent assembly, but also reduce the gap between the side plate 2 and the insulating film body 1 by hot-melt connection, prevent the electrolyte from penetrating and corroding the housing and the explosion-proof valve, extend the service life of the housing and the explosion-proof valve, and improve the safety performance of the battery.

[0058] It can be understood that the connection method between the positioning protrusions and the insulating film body 1 and the connection method between the insulating film body 1 and the side plate 2 can both be adjusted according to actual needs, and no more details will be described here.

[0059] Refer to Figure 6 and Figure 7, in some embodiments, the diameter of the positioning convex hull is D1, the diameter of the positioning hole 21 is D2, and D1 + 0.1 mm ≤ D2 ≤ D1 + 6 mm is satisfied. In this embodiment, the positioning convex hull and the positioning hole 21 are coaxially arranged. Exemplarily, when D2 = D1 + 0.1 mm, the distance between the positioning convex hull and the positioning hole 21 is 0.05 mm. Thus, the diameter D2 of the positioning hole 21 is slightly larger than the diameter D1 of the positioning convex hull, which can provide sufficient space for the assembly of the positioning convex hull, improve the assembly efficiency, and realize the positioning of the side plate 2 and the insulating film body 1 through the cooperation between the positioning convex hull and the positioning hole 21.

[0060] It can be understood that the diameter D2 of the positioning hole 21 cannot be too small, otherwise it will affect the assembly of the positioning convex hull, increase the assembly difficulty, and the side plate 2 will squeeze the positioning convex hull during the assembly process, causing the positioning convex hull to deform or be damaged. The diameter D2 of the positioning hole 21 cannot be too large either, otherwise the positioning convex hull will be prone to looseness in the positioning hole 21, which is not conducive to positioning the insulating film body 1 and the side plate 2.

[0061] Refer to Figure 1 , in some embodiments, the thickness of the side plate 2 is H2, and 0.15 mm ≤ H2 ≤ 2 mm is satisfied. The thickness of the insulating film body 1 is H3, and 0.1 mm ≤ H3 ≤ 0.3 mm is satisfied. Among them, in this embodiment, the thickness H2 of the side plate 2 can be any value between 0.15 mm and 2 mm or the range between any two values, such as 0.15 mm, 0.2 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm, etc.; the thickness H3 of the insulating film body 1 can be any value between 0.1 mm and 0.3 mm or the range between any two values, such as 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, etc.

[0062] Thus, the insulating film body 1 and the side plate 2 can have better structural strength, so that after covering the electrode group, they can play a role in protecting and insulating the electrode group. In the thickness range of 0.1 mm - 0.3 mm, the heat fusion connection between the insulating film body 1 and the side plate 2 can achieve more uniform heat transfer and welding effect, enabling the insulating film body 1 and the side plate 2 to be closely combined, avoiding connection failure caused by poor local welding or over-welding, reducing the gap between the insulating film body 1 and the side plate 2, and preventing electrolyte from penetrating and corroding the housing and the explosion-proof valve.

[0063] It can be understood that the thickness H2 of the side plate 2 cannot be too thin, as being too thin will cause the side plate 2 to be prone to bending and warping, which is not conducive to assembly. Nor can the thickness H2 of the side plate 2 be too thick, as being too thick will occupy too much internal space of the battery and is not conducive to heat dissipation. The thickness H3 of the insulating film body 1 cannot be too thin, as being too thin will result in low structural strength and poor insulation performance of the insulating film body 1, making it difficult to protect the electrode group and thermally fuse with the side plate 2. Nor can the thickness H3 of the insulating film body 1 be too thick, as being too thick will affect the heat dissipation performance of the insulating film body 1 and increase the weight and volume of the insulating film body 1, which is not conducive to lightweighting. The thickness H2 of the side plate 2 and the thickness H3 of the insulating film body 1 can be adjusted according to actual needs, and will not be listed in detail here.

[0064] In order to verify the rationality of the ranges of the height H1 of the positioning convex hull, the thickness H2 of the side plate 2, the thickness H3 of the insulating film body 1, the spacing L1 between the two positioning convex hulls, the width L2 of the insulating film body 1, the diameter D1 of the positioning convex hull, and the diameter D2 of the positioning hole 21, as shown in Table 1, this embodiment provides ten sets of examples and ten sets of comparative examples for illustration.

[0065] Table 1

[0066]

[0067] As can be seen from Examples 1 to 10 in Table 1, after meeting the defined ranges, the positioning convex hull is not higher than the side plate 2 and will not interfere with the internal electrode group. The spacing between the positioning convex hulls is appropriate, so that the positioning convex hull will not shift when connected to the side plate 2, improving the connection stability between the insulating film body 1 and the side plate 2.

[0068] As can be seen from Comparative Examples 1 and 2 in Table 1, when the height H1 of the positioning convex hull is greater than the thickness H3 of the side plate 2, the positioning convex hull protrudes from the side plate 2 and causes interference with the electrode group, affecting the assembly effect.

[0069] As can be seen from Comparative Examples 3 and 4 in Table 1, when the spacing between the positioning holes 21 is too close (that is, the spacing L1 between the two positioning convex hulls is too small), the distance between the positioning hole 21 and the end face of the side plate 2 will be too large, causing the side plate to shake easily and affecting the wrapping of the electrode group.

[0070] As can be seen from Comparative Examples 5 and 6 in Table 1, when the spacing between the positioning holes 21 is too far (that is, the spacing L1 between the two positioning convex hulls is too large), the distance between the positioning hole 21 and the end face of the side plate 2 will be too small, and the middle part of the side plate 2 is prone to bulge, and the edge of the insulating film body 1 is prone to wrinkle, affecting the flatness of the insulating film body 1 and causing wrinkles when the insulating film body 1 wraps the electrode group.

[0071] As can be seen from Comparative Example 7 and Comparative Example 8 in Table 1, when the distance between the positioning hole 21 and the positioning boss is too small or there is zero clearance, assembly interference will occur between the positioning boss and the positioning hole 21, making it difficult for the side plate 2 to fit with the insulating film body 1.

[0072] As can be seen from Comparative Example 9 and Comparative Example 10 in Table 1, when the distance between the positioning hole 21 and the positioning boss is too large, the positioning boss is likely to become loose within the positioning hole 21, causing the side plate 2 to shift and making it difficult to achieve positioning.

[0073] Refer to Figure 5 , in some embodiments, the side plate 2 is provided with a plurality of material-reducing holes 22. Along the symmetry axis in the width direction of the side plate 2, the plurality of material-reducing holes 22 are symmetrically arranged on the side plate 2. In this embodiment, the plurality of material-reducing holes 22 are arranged at intervals on the side plate 2.

[0074] In this way, providing the material-reducing holes 22 on the side plate 2 can not only make the side plate 2 lighter, but also form a plurality of exhaust channels, improve the exhaust efficiency of the gas inside the battery, guide the gas flow to the explosion-proof valve when the internal pressure of the battery rises, achieve rapid pressure relief, avoid deformation of the housing due to excessive air pressure, and the symmetrically arranged material-reducing holes 22 can make the structure of the side plate 2 relatively stable, so that the side plate 2 can provide stable support for the electrode group after being connected to the insulating film body 1.

[0075] It can be understood that the shape, quantity, and setting position of the material-reducing holes 22 can all be adjusted according to actual needs. In this embodiment, a plurality of material-reducing holes 22 are provided at the position of the side plate 2 corresponding to the explosion-proof valve for the convenience of exhaust.

[0076] Refer to Figure 1 , the present invention provides a battery, including an electrode group, a housing, and an insulating film assembly. The insulating film body 1 is arranged between the electrode group and the housing.

[0077] In this embodiment, along the height direction of the housing, the electrode group, the side plate 2, the insulating film body 1, and the housing are arranged in sequence.

[0078] In this way, the insulating film body 1 arranged between the electrode group and the housing can isolate the electrode group and the housing, reducing the risk of short circuit. The side plate 2 and the insulating film body 1 can fix the relative position through the cooperation of the positioning boss and the positioning hole 21 and heat fusion connection, avoiding the shift of the side plate 2 during the battery assembly process, and the side plate 2 can be stably attached to the insulating film body 1, preventing the electrolyte from penetrating through the gap between the side plate 2 and the insulating film body 1 and corroding the housing and the explosion-proof valve.

[0079] Refer to Figure 1, in some embodiments, there are two positioning holes 21. An explosion-proof valve is provided on the bottom surface of the housing. Along the thickness direction of the bottom surface of the housing, the projection of the explosion-proof valve is correspondingly arranged between the projections of the two positioning holes 21. That is, the material-reducing hole 22 provided corresponding to the position of the explosion-proof valve is located between the two positioning holes 21, and material-reducing holes 22 are also symmetrically arranged on the sides of the two positioning holes 21 away from each other.

[0080] In this way, the gas generated by the battery can be discharged to the explosion-proof valve through the material-reducing hole 22 to achieve rapid exhaust. The two positioning holes 21 are respectively arranged on both sides in the length direction of the explosion-proof valve, which can improve the structural stability of the side plate 2, ensure that the insulating film body 1 is closely attached to the side plate 2 while allowing the gas inside the battery to be discharged smoothly, avoid the electrolyte from corroding the housing and the explosion-proof valve, and improve the safety and stability of the battery.

[0081] It can be understood that the setting position of the positioning hole 21 can be adjusted according to actual needs, as long as it can facilitate the rapid positioning of the installation position of the side plate 2 on the insulating film body 1 and allow the side plate 2 to have enough space to achieve hot melting connection with the insulating film body 1, and no more examples will be listed here.

[0082] The assembly process of the insulating film assembly is as follows:

[0083] Lay the insulating film body 1 flat, and address and position it through a CCD (Charge Coupled Device) camera to make it locate at the position of the positioning convex hull. Align the positioning hole 21 of the side plate 2 with the positioning convex hull of the insulating film body 1 through a clamping tooling, make the positioning convex hull and the positioning hole 21 engage with each other, and achieve close fitting between the side plate 2 and the insulating film body 1 in the non-perforated area through hot melting. Finally, wrap the insulating film body 1 assembled with the side plate 2 around the electrode group, make the insulating film body 1 overlap on the top surface of the electrode group (that is, the end away from the side plate 2) after surrounding the electrode group, and fix the overlapping part by gluing to achieve the assembly of the insulating film body 1 and the electrode group.

[0084] Obviously, the above embodiments of the present invention are only examples for clearly explaining the present invention, and are not limitations on the implementation manners of the present invention. For those of ordinary skill in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the implementation manners here. Any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the claims of the present invention.

Claims

1. An insulating film assembly, characterized in that: Connected to the electrode group, the insulating film assembly includes: An insulating film body (1), the insulating film body (1) covers the pole group, and a positioning piece (11) is provided on one side of the insulating film body (1); A side plate (2), wherein a positioning hole (21) is provided on the side plate (2) at a position corresponding to the positioning member (11), and the positioning member (11) is clamped in the positioning hole (21) so as to connect the side plate (2) with the insulating film body (1).

2. The insulating film assembly according to claim 1, characterized in that: The side plate (2) is arranged on a side of the insulating film body (1) facing the pole group, or the side plate (2) is arranged on a side of the insulating film body (1) facing away from the pole group.

3. The insulating film assembly according to claim 1, characterized in that: The positioning member (11) is a positioning convex bump, and the positioning convex bump is integrally formed and arranged on the insulating film body (1).

4. The insulating film assembly according to claim 3, characterized in that: The height of the positioning convex bump is H1, the thickness of the side plate (2) is H2, and H1≤H2 is satisfied.

5. The insulating film assembly according to claim 3, characterized in that: Two positioning holes (21) are provided, and the two positioning holes (21) are respectively opened at two ends of the side plate (2), and the positioning convex bumps are provided in a one-to-one correspondence with the positioning holes (21).

6. The insulating film assembly according to claim 5, characterized in that: The distance between the two positioning convex bumps is L1, the width of the insulating film body (1) is L2, and 1 / 3L2≤L1≤L2-10mm is satisfied.

7. The insulating film assembly according to claim 3, characterized in that: The diameter of the positioning convex hull is D1, the diameter of the positioning hole (21) is D2, and the relationship D1+0.1mm≤D2≤D1+6mm is satisfied.

8. The insulating film assembly according to any one of claims 1 to 7, characterized in that: The thickness of the side plate (2) is H2, and satisfies 0.15mm≤H2≤2mm; and / or the thickness of the insulating film body (1) is H3, and satisfies 0.1mm≤H3≤0.3mm.

9. A battery, characterized in that: It comprises a pole group, a shell and an insulating film assembly as claimed in any one of claims 1 to 8, wherein the insulating film body (1) is arranged between the pole group and the shell.

10. The battery according to claim 9, characterized in that Two positioning holes (21) are provided, and an explosion-proof valve is provided on the bottom surface of the shell. Along the thickness direction of the bottom surface of the shell, the projection of the explosion-proof valve is correspondingly arranged between the projections of the two positioning holes (21).

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