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, a side plate and a positioning stand column, and the insulating film body wraps the pole group; the side plates are connected with the insulating film body; the positioning stand columns are arranged on the side plates, the insulating film body is correspondingly provided with positioning holes for the positioning stand columns to penetrate through, and the positioning stand columns have a limiting state, so that when the positioning stand columns are in the limiting state, the side plates tightly abut against the insulating film body to limit the relative positions of the insulating film body and the side plates. Thus, the side plates and the insulating film body can be positioned and assembled through the positioning stand columns and the positioning holes, when the positioning stand columns are in the limiting state, the side plates and the insulating film body tightly abut against each other, gaps between the side plates and the insulating film body are reduced, and electrolyte is prevented from corroding a shell and an anti-explosion valve; the positioning stand columns can support the pole groups and the insulating film bodies and form exhaust channels between the insulating film bodies, so that the exhaust efficiency is improved.

Description

Technical Field

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

[0002] A battery is a common energy storage device. As a power battery, a lithium-ion battery is widely used in electric vehicles and the energy storage field.

[0003] A battery includes a battery cell and a housing. In the application of a long battery cell lithium-ion battery, an explosion-proof valve is usually arranged at the bottom of the housing to achieve thermoelectric separation, thereby improving the safety of the battery cell. In addition, the outside of the electrode assembly is wrapped with an electrode assembly insulating film and side plates for insulation protection.

[0004] However, during the assembly process, the insulating film is provided with holes for engaging with the side plates, so that the combination of the insulating film and the side plates may not be tight enough, resulting in a gap between the two, thereby causing the electrolyte to seep out, connecting the electrode assembly and the bottom of the housing and triggering a short circuit, causing corrosion of the housing, and the notched part of the explosion-proof valve is relatively weak and is easily corroded by the electrolyte, thus resulting in phenomena such as liquid leakage and gas leakage, affecting the normal use of the explosion-proof valve; when the insulating film is tightly attached to the housing, it is not conducive to the rapid discharge of the gas inside the battery to the explosion-proof valve. Summary of the Invention

[0005] The purpose of the present invention is to provide an insulating film assembly and a battery to solve the problems that the electrolyte easily seeps out through the gap between the insulating film and the side plates and corrodes the housing and the explosion-proof valve, and the exhaust efficiency of the battery is relatively low.

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

[0007] In a first aspect, an insulating film assembly is connected to an electrode assembly. The insulating film assembly includes: an insulating film body, the insulating film body is arranged to cover the electrode assembly; a side plate, the side plate is connected to the insulating film body; a positioning column, the positioning column is arranged on the side plate, and the insulating film body is correspondingly provided with a positioning hole for the positioning column to pass through. The positioning column has a limiting state, so that when the positioning column is in the limiting state, the side plate is in close contact with the insulating film body to limit the relative positions of the insulating film body and the side plate.

[0008] Preferably, two positioning columns are provided, and the two positioning columns are respectively arranged at both ends of the side plate, and the positioning holes are arranged in one-to-one correspondence with the positioning columns.

[0009] Preferably, the positioning column also has an assembled state. When the positioning column is in the assembled state, the cross-sectional area of the end of the positioning column away from the side plate is smaller than the cross-sectional area of the positioning hole. When the positioning column is in the limiting state, the cross-sectional area of the end of the positioning column away from the side plate is larger than the cross-sectional area of the positioning hole.

[0010] Preferably, the thickness of the insulating film body is H1, the height of the positioning column when in the assembled state is H2, and 0.30 mm ≤ H2 - H1 ≤ 0.65 mm; and / or, the maximum diameter of the positioning column when in the assembled state is D1, the diameter of the positioning hole is D2, and 0.05 mm ≤ D2 - D1 ≤ 0.30 mm.

[0011] Preferably, the height of the positioning column when in the limiting state is H3, and 0.10 mm ≤ H3 ≤ 0.15 mm; and / or, the cross-sectional area of the positioning hole is S1, the cross-sectional area of the positioning column when in the limiting state is S2, and 14% ≤ S1 / S2 ≤ 84%.

[0012] Preferably, when the positioning column is in the assembled state, the positioning column is in a frustum structure.

[0013] Preferably, the positioning column is made of a plastically deformable material so that the positioning column forms the limiting state through deformation.

[0014] Preferably, the positioning column and the side plate are integrally formed.

[0015] Preferably, the side plate is provided with a plurality of through holes, and the plurality of through holes are symmetrically arranged along the symmetry axis in the width direction of the side plate.

[0016] 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.

[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, a side plate, and a positioning column. The insulating film body is disposed to cover the pole group; the side plate is connected to the insulating film body; the positioning column is disposed on the side plate, and the insulating film body is correspondingly provided with a positioning hole for the positioning column to pass through. The positioning column has a limiting state, so that when the positioning column is in the limiting state, the side plate and the insulating film body are in close contact to limit the relative positions of the insulating film body and the side plate.

[0019] Thus, by inserting the positioning column into the positioning hole, the preliminary positioning of the side plate on the insulating film body can be achieved. When the positioning column is in the limit state, the side plate is in close contact with the insulating film body, improving the sealing performance and connection stability at the joint between the side plate and the insulating film body, preventing the electrolyte from leaking through the gap between the side plate and the insulating film body and corroding the housing and the explosion-proof valve, enhancing the safety of the battery. Moreover, one end of the positioning column facing away from the side plate and the side plate are respectively located on both sides of the insulating film body. While providing stable support for the electrode group and the insulating film body, an exhaust channel can be formed between the insulating film bodies, improving the exhaust efficiency of the battery. Description of the Drawings

[0020] Figure 1 is a schematic structural view of the insulating film body in an embodiment of the present invention;

[0021] Figure 2 is a partial side view of the insulating film body in an embodiment of the present invention;

[0022] Figure 3 is a partial side view of the insulating film assembly when the positioning column is in the assembled state in an embodiment of the present invention;

[0023] Figure 4 is a partial side view of the insulating film assembly when the positioning column is in the limit state in an embodiment of the present invention;

[0024] Figure 5 is a schematic structural view of the side plate and the positioning column in an embodiment of the present invention;

[0025] Figure 6 is a schematic structural view of the insulating film assembly in an embodiment of the present invention;

[0026] Figure 7 is a side view of the insulating film assembly in an embodiment of the present invention;

[0027] Figure 8 is in an embodiment of the present invention Figure 7 Enlarged view of part A.

[0028] In the figure:

[0029] 1. Insulating film body; 11. Positioning hole; 2. Side plate; 21. Through hole; 3. Positioning column; 4. Housing. Detailed Embodiments

[0030] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only for explaining the present invention, rather than limiting the present invention. Additionally, it should be noted that for the sake of description, only parts related to the present invention are shown in the drawings, not all structures.

[0031] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral body; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between two elements. 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 circumstances.

[0032] 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 between 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 the upper part", and "on the upper surface" of the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "below the lower part", and "on the lower surface" of the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0033] In the description of this embodiment, the orientation or positional relationship terms such as "upper", "lower", "right", etc. are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description and simplifying the operation, 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, so it cannot be understood 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.

[0034] Refer to Figures 1 to 4 , 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, side plates 2, and positioning columns 3. The insulating film body 1 is wrapped around the pole group; the side plates 2 are connected to the insulating film body 1; the positioning columns 3 are arranged on the side plates 2, and the insulating film body 1 is correspondingly provided with positioning holes 11 for the positioning columns 3 to pass through. The positioning columns 3 have a limiting state, such that when the positioning columns 3 are in the limiting state, the side plates 2 are in close contact with the insulating film body 1 to limit the relative positions of the insulating film body 1 and the side plates 2.

[0035] In this embodiment, the positioning holes 11 are arranged in the middle of the insulating film body 1, so that when the positioning columns 3 pass through the positioning holes 11, the side plates 2 are located in the middle of the insulating film body 1. When the insulating film body 1 with the side plates 2 assembled is wrapped around the pole group, the side plates 2 are located below the bottom surface of the pole group, and the overlapping area of the insulating film body 1 is located on the top surface or the bottom surface of the pole group, so that the insulating film body 1 can protect the top surface, bottom surface, and side wall of the pole group.

[0036] In this way, the side plate 2 and the insulating film body 1 are positioned and assembled through the positioning columns 3 and the positioning holes 11, which can improve the positioning efficiency and the assembly efficiency. By keeping the positioning columns 3 in a limited state, the side plate 2 and the insulating film body 1 are tightly abutted, improving the connection stability between the side plate 2 and the insulating film body 1, reducing the gap at the connection between the insulating film body 1 and the side plate 2, preventing the electrolyte from leaking through the gap and corroding the housing 4 and the explosion-proof valve (not shown in the figure), improving the safety of the battery. Moreover, one end of the positioning column 3 away from the side plate 2 and the side plate 2 are respectively located on both sides of the insulating film body 1, which can form an exhaust channel between the insulating film body 1 and the housing 4, facilitating the rapid discharge of the gas inside the battery to the explosion-proof valve and improving the battery exhaust efficiency.

[0037] It can be understood that the overlapping area position of the insulating film body 1 can be adjusted according to actual needs, as long as the thickness of the insulating film body 1 on both sides of the electrode group is uniform, which is convenient for assembling the electrode group into the housing 4.

[0038] Refer to Figure 4 and Figure 5 In some embodiments, two positioning columns 3 are provided, and the two positioning columns 3 are respectively arranged at both ends of the side plate 2, and the positioning holes 11 are arranged in one-to-one correspondence with the positioning columns 3, that is, two positioning holes 11 are correspondingly arranged.

[0039] In this embodiment, the two positioning columns 3 are symmetrically arranged at both ends of the side plate 2, so that when the positioning columns 3 are connected to the positioning holes 11, the length direction of the side plate 2 is parallel to the length direction of the electrode group.

[0040] In this way, by symmetrically arranging two positioning columns 3 at both ends of the side plate 2, the installation position of the side plate 2 on the insulating film body 1 can be quickly positioned, the connection stability between the insulating film body 1 and the side plate 2 is improved, both ends of the side plate 2 can be fixedly arranged on the insulating film body 1, and the side plate 2 and the insulating film body 1 are tightly attached, preventing the electrolyte from seeping out through the gap between the insulating film and the side plate 2 and corroding the housing 4 and the explosion-proof valve, improving the stability and safety of the battery. When gas is generated inside the battery, the gas can be quickly discharged to the explosion-proof valve through the exhaust channel formed by the gap between the insulating film body 1 and the housing 4, improving the battery exhaust efficiency.

[0041] It can be understood that the number of the positioning columns 3 is not limited to two, and can also be four, six, etc. It should be noted that the number of the positioning columns 3 and the positioning holes 11 cannot be too many, otherwise the structural strength of the position where the positioning holes 11 are opened on the insulating film body 1 will be relatively low. The number of the positioning columns 3 can be adjusted according to actual needs and will not be listed in detail here.

[0042] Refer to Figure 3In some embodiments, the positioning column 3 also has an assembly state. When the positioning column 3 is in the assembly state, the cross-sectional area of ​​the end of the positioning column 3 away from the side plate 2 is smaller than the cross-sectional area of ​​the positioning hole 11. When the positioning column 3 is in the limited state, the cross-sectional area of ​​the end of the positioning column 3 away from the side plate 2 is larger than the cross-sectional area of ​​the positioning hole 11.

[0043] In the present embodiment, when the positioning column 3 is in the assembly state, it can freely extend into the positioning hole 11. At this time, the role of the positioning column 3 is to realize the preliminary positioning of the side panel 2 on the insulating film body 1. When the positioning column 3 is in the limiting state, since the end of the positioning column 3 away from the side panel 2 and the side panel 2 are respectively located on both sides of the insulating film body 1, and the cross-sectional area of ​​the end of the positioning column 3 away from the side panel 2 is larger than the cross-sectional area of ​​the positioning hole 11, it is possible to limit the relative position of the side panel 2 and the insulating film body 1, thereby completing the assembly of the side panel 2.

[0044] In this way, when the positioning column 3 is in the assembly state, the cross-sectional area of ​​the end of the positioning column 3 facing away from the side plate 2 is smaller, which can facilitate the staff to extend the positioning column 3 into the positioning hole 11 to achieve the initial positioning of the side plate 2, thereby improving the assembly efficiency and accuracy. When the positioning column 3 is in the limiting state, the side plate 2 can be tightly fitted with the insulating film body 1, reducing the gap at the connection between the insulating film body 1 and the side plate 2, avoiding electrolyte leakage and corrosion of the shell 4 and the explosion-proof valve, and forming an exhaust channel between the insulating film body 1 and the shell 4, which is convenient for quickly discharging the gas inside the battery to the explosion-proof valve, thereby improving the battery exhaust efficiency.

[0045] It can be understood that the length of the positioning column 3 can be adjusted according to actual needs. By adjusting the length of the positioning column 3, the distance between the insulating membrane body 1 and the shell 4 (that is, the height of the exhaust channel) can be adjusted, so that the gas inside the battery can be discharged to the outside through the explosion-proof valve in time. No further details will be given here.

[0046] See also Figure 3 and Figure 4 In some embodiments, the thickness of the insulating film body 1 is H1, the height of the positioning column 3 when in the assembly state is H2, and satisfies 0.30mm≤H2-H1≤0.65mm, the maximum diameter of the positioning column 3 when in the assembly state is D1, the diameter of the positioning hole 11 is D2, and satisfies 0.05mm≤D2-D1≤0.30mm.

[0047] In this embodiment, the thickness H1 of the insulating film body 1 satisfies 0.10 mm ≤ H1 ≤ 0.15 mm. The thickness H1 of the insulating film body 1 can be any value between 0.10 mm and 0.15 mm or the range between any two values, such as 0.10 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, etc. The height H2 of the positioning column 3 in the assembled state can be any value between 0.40 mm and 0.80 mm or the range between any two values, such as 0.40 mm, 0.50 mm, 0.60 mm, 0.70 mm, 0.80 mm, etc. After the positioning column 3 in the assembled state is inserted into the positioning hole 11, the end of the positioning column 3 facing away from the side plate 2 protrudes from the positioning hole 11. The difference between the height H2 of the positioning column 3 in the assembled state and the thickness H1 of the insulating film body 1 can be any value between 0.30 mm and 0.65 mm or the range between any two values, such as 0.30 mm, 0.40 mm, 0.50 mm, 0.60 mm, 0.65 mm, etc.; the difference between the diameter D2 of the positioning hole 11 and the maximum diameter D1 of the positioning column 3 in the assembled state can be any value between 0.05 mm and 0.30 mm or the range between any two values, such as 0.05 mm, 0.10 mm, 0.15 mm, 0.20 mm, 0.25 mm, 0.30 mm, etc.

[0048] In this way, after the positioning column 3 is inserted into the positioning hole 11, the positioning column 3 in the limited state can limit the position of the side plate 2 on the insulating film body 1. And because there is a gap between the positioning hole 11 and the positioning column 3, the assembly effect of the positioning column 3 can be improved, realizing the tight abutment between the insulating film body 1 and the side plate 2, and avoiding the existence of a gap between the insulating film body 1 and the side plate 2 and preventing the electrolyte from corroding the housing 4 and the explosion-proof valve.

[0049] It can be understood that the difference between the height H2 of the positioning column 3 in the assembled state and the thickness H1 of the insulating film body 1 cannot be too small. If it is too small, the limiting effect of the positioning column 3 will be poor, resulting in loosening of the side plate 2 and reducing the connection stability between the side plate 2 and the insulating film body 1. The difference between the height H2 of the positioning column 3 in the assembled state and the thickness H1 of the insulating film body 1 cannot be too large either. If it is too large, the positioning column 3 will occupy too much space, resulting in a large gap between the side plate 2 and the housing 4 and reducing the space utilization rate inside the housing 4; the difference between the diameter D2 of the positioning hole 11 and the maximum diameter D1 of the positioning column 3 in the assembled state cannot be too small. If it is too small, the assembly will be difficult. The difference between the diameter D2 of the positioning hole 11 and the maximum diameter D1 of the positioning column 3 in the assembled state cannot be too large either. If it is too large, the positioning column 3 will be loose in the positioning hole 11 and it will be difficult to limit the relative position between the insulating film body 1 and the side plate 2.

[0050] Refer toFigure 3 and Figure 4 In some embodiments, when the positioning column 3 is in the limit state, its height is H3, and 0.10 mm ≤ H3 ≤ 0.15 mm is satisfied. The cross-sectional area of the positioning hole 11 is S1, and the cross-sectional area of the positioning column 3 when it is in the limit state is S2, and 14% ≤ S1 / S2 ≤ 84% is satisfied.

[0051] It should be noted that the height H3 of the positioning column 3 when it is in the limit state does not include the height of the positioning hole 11. That is to say, the height H3 of the positioning column 3 when it is in the limit state is the height by which the positioning column 3 protrudes from the positioning hole 11.

[0052] In this embodiment, the height H3 of the positioning column 3 when it is in the limit state can be any value between 0.10 mm and 0.15 mm or the range between any two values, such as 0.10 mm, 0.11 mm, 0.12 mm, 0.13 mm, 0.14 mm, 0.15 mm, etc.; the ratio of the cross-sectional area S1 of the positioning hole 11 to the cross-sectional area S2 of the positioning column 3 when it is in the limit state can be any value between 14% and 84% or the range between any two values, such as 14%, 24%, 34%, 44%, 54%, 64%, 74%, 84%, etc.

[0053] In this way, since the cross-sectional area S2 of the positioning column 3 when it is in the limit state is larger than the cross-sectional area S1 of the positioning hole 11, the clamping connection between the positioning column 3 and the insulating film body 1 can be realized, and the positioning column 3 can be prevented from falling off from the positioning hole 11, so that the side plate 2 and the insulating film body 1 can be tightly connected without the need for an opening step, and the corrosion of the housing 4 and the explosion-proof valve by the electrolyte due to the gap between the side plate 2 and the insulating film body 1 can be avoided.

[0054] It can be understood that the height H3 of the positioning column 3 when it is in the limit state cannot be too small, otherwise it will reduce the structural strength of the connection between the positioning column 3 and the insulating film body 1, reduce the limiting effect of the positioning column 3, increase the risk of loosening of the side plate 2, and is not conducive to forming an exhaust channel. The height H3 of the positioning column 3 when it is in the limit state cannot be too large either, otherwise it will occupy too much internal space of the housing 4, reduce the space utilization rate, and cause material waste; the ratio of the cross-sectional area S1 of the positioning hole 11 to the cross-sectional area S2 of the positioning column 3 when it is in the limit state cannot be too small, otherwise the positioning column 3 is likely to loosen or fall off, reducing the connection effect between the side plate 2 and the insulating film body 1. The ratio of the cross-sectional area S1 of the positioning hole 11 to the cross-sectional area S2 of the positioning column 3 when it is in the limit state cannot be too large either, otherwise it will cause material waste and increase the risk of assembly interference with other structures in the housing 4.

[0055] Refer to Figure 3 and Figure 4In some embodiments, the positioning column 3 is made of a plastically deformable material so that the positioning column 3 can be deformed to form a limiting state.

[0056] In this embodiment, the positioning column 3 is made of plastic material, and the positioning column 3 is set on the side plate 2 through an injection molding process. The positioning column 3 is converted from an assembly state to a limiting state through a hot melt process, so that the side plate 2 is fixedly set on the insulating film body 1.

[0057] In this way, the end of the positioning column 3 facing away from the side plate 2 is hot-melted and expands in the radial direction, so that its cross-sectional area is increased, and the side plate 2 and the insulating film body 1 can be tightly clamped in the limited state, thereby improving the sealing and connection stability of the connection between the side plate 2 and the insulating film body 1, and reducing the gap between the side plate 2 and the insulating film body 1 to prevent the electrolyte from seeping through the gap and contacting the shell 4 and the explosion-proof valve. Since the shape of the positioning column 3 is fixed after hot-melting, it can not only keep the side plate 2 and the insulating film body 1 tightly connected, but also have sufficient structural strength to support the side plate 2 and the pole group, improve the stability of the pole group in the shell 4, and form an exhaust channel between the insulating film body 1 and the bottom surface of the shell 4, thereby improving the battery exhaust efficiency.

[0058] It can be understood that the material of the positioning column 3 can be adjusted according to actual needs, and can also be a material such as resin, or the positioning column 3 can be a rivet structure to achieve riveting between the side panel 2 and the insulating film assembly. The material and specific structure of the positioning column 3 can be adjusted according to actual needs, and no further examples are given here.

[0059] See also Figure 3 In some embodiments, when the positioning column 3 is in the assembled state, the positioning column 3 is a truncated cone structure. In this embodiment, the cross-sectional area of ​​the end of the positioning column 3 away from the side plate 2 is smaller than the cross-sectional area of ​​the end connected to the side plate 2, so as to facilitate the plugging of the side plate 2 with the insulation film body 1.

[0060] In this way, the positioning column 3 with a frustum structure can be easily inserted into the positioning hole 11 to position the side plate 2, improving the assembly efficiency. Since the end with a smaller cross-sectional area of the frustum structure enters the positioning hole 11 first, the resistance when the positioning column 3 is inserted into the positioning hole 11 can be reduced, avoiding deformation or tearing of the position where the positioning hole 11 is opened on the insulating film body 1 due to an overly large cross-sectional area, and further avoiding the generation of gaps at the connection between the insulating film body 1 and the side plate 2, improving the reliability and sealing performance of the overall structure of the insulating film body 1, preventing the housing 4 and the explosion-proof valve from being corroded by the electrolyte, and extending the service life of the battery; when the positioning column 3 deforms under the action of heat melting and the cross-sectional area of the end of the positioning column 3 away from the side plate 2 increases, a self-locking structure can be formed between the insulating film body 1 and the side plate 2, making it difficult for the side plate 2 to loosen or shift, improving the connection stability between the side plate 2 and the insulating film body 1. The positioning column 3 can provide support for the electrode group and the insulating film body 1, optimize the air flow path, and improve the exhaust efficiency of the battery.

[0061] It can be understood that the positioning column 3 can also be a cylindrical structure, a conical structure, etc., as long as it can stably assemble the side plate 2 to the insulating film body 1 and keep the connection between the side plate 2 and the insulating film body 1 sealed. The shape of the positioning column 3 can be flexibly adjusted and will not be listed in detail here.

[0062] Refer to Figure 4 , in some embodiments, when the positioning column 3 is in the limiting state, the side plate 2 is located on the side of the insulating film body 1 facing the electrode group. That is, when the insulating film body 1 wraps the electrode group, the side plate 2 is located between the electrode group and the insulating film body 1, and the end of the positioning column 3 away from the side plate 2 is located between the insulating film body 1 and the housing 4.

[0063] In this way, when the positioning column 3 is in the limiting state, it can support the insulating film body 1 and the electrode group, and form an exhaust channel between the insulating film body 1 and the housing 4, facilitating the rapid discharge of gas to the explosion-proof valve. Moreover, the side plate 2 can abut against the electrode group to block the penetration of the electrolyte, prevent the housing 4 and the explosion-proof valve from being corroded by the electrolyte, and improve the insulation performance and structural strength between the electrode group and the housing 4, thereby improving the safety of the battery.

[0064] It can be understood that if the end of the positioning column 3 away from the side plate 2 is arranged on the side of the insulating film body 1 facing the electrode group, it will interfere with the electrode group.

[0065] Refer to Figure 5 , in some embodiments, the positioning column 3 and the side plate 2 are integrally formed. In this embodiment, both the positioning column 3 and the side plate 2 are made of plastic materials.

[0066] In this way, the positioning column 3 and the side plate 2 are integrally formed, which facilitates the processing of the side plate 2, makes the position of the positioning column 3 on the side plate 2 more accurate, and realizes a sealed connection between the positioning column 3 and the side plate 2, avoiding the influence on the positioning of the side plate 2 and the insulating film body 1 due to the offset or looseness of the positioning column 3 and the side plate 2, reducing the assembly error, and improving the assembly efficiency. Moreover, the positioning column 3 and the side plate 2 made of plastic material have good insulation performance, improving the insulation isolation effect between the electrode group and the housing 4. The side plate 2 is tightly connected to the insulating film body 1, so that while the side plate 2 provides stable support for the electrode group, the sealing performance at the connection between the side plate 2 and the insulating film body 1 is maintained, avoiding the leakage of the electrolyte through the gap between the side plate 2 and the insulating film body 1 to contact the housing 4 and the explosion-proof valve. The positioning columns 3 provided at both ends of the side plate 2 can improve the overall strength of the side plate 2 and form a stable exhaust channel between the insulating film body 1 and the housing 4, facilitating the discharge of the gas inside the battery.

[0067] It can be understood that the connection manner between the positioning column 3 and the side plate 2 can also be bonding, plugging, etc., and the materials of the positioning column 3 and the side plate 2 can be adjusted according to actual needs, which will not be elaborated here.

[0068] Refer to Figure 6 , in some embodiments, along the length direction of the electrode group, the length of the side plate 2 is less than the length of the insulating film body 1.

[0069] In this embodiment, when the insulating film body 1 wraps the electrode group, there are distances between the long side of the side plate 2 and the long side of the bottom surface of the housing 4, and between the short side of the side plate 2 and the short side of the bottom surface of the housing 4.

[0070] In this way, the distance between the side plate 2 and the housing 4 can form an additional air flow channel, reducing gas retention and improving the battery exhaust efficiency. Moreover, the insulating film body 1 and the side plate 2 are tightly connected, which can block the penetration of the electrolyte and corrode the housing 4 and the explosion-proof valve, improving the durability and safety of the battery; the area of the side plate 2 is small, which can improve the assembly tolerance, reduce the assembly difficulty, and keep the side plate 2 with sufficient supporting force.

[0071] It can be understood that the length of the side plate 2 can be adjusted according to the sizes of the electrode group and the housing 4, which will not be elaborated here.

[0072] Refer to Figure 5 and Figure 6 , in some embodiments, the side plate 2 is provided with a plurality of through holes 21, and the plurality of through holes 21 are symmetrically arranged along the symmetry axis in the width direction of the side plate 2.

[0073] In this embodiment, the plurality of through holes 21 are arranged at intervals, and the through holes 21 extend along the thickness direction of the side plate 2, and the through holes 21 are provided on both sides of the positioning column 3.

[0074] In this way, the heat exchange area between the side plate 2 and the surrounding environment can be enhanced, the heat dissipation efficiency can be improved, the through holes 21 can form multiple exhaust channels, facilitating the rapid discharge of the gas inside the battery through the through holes 21 to the exhaust channel between the insulating film body 1 and the housing 4, and being quickly discharged to the outside through the explosion-proof valve, improving the battery exhaust efficiency, and being able to reduce the weight of the side plate 2 to achieve a lightweight design.

[0075] It can be understood that the number and setting positions of the through holes 21 can be adjusted according to actual needs and will not be elaborated here.

[0076] In order to verify the rationality of the ranges of the maximum diameter D1 of the positioning post 3 in the assembled state, the diameter D2 of the positioning hole 11, the thickness H1 of the insulating film body 1, the height H2 of the positioning post 3 in the assembled state, the height H3 of the positioning post 3 in the limited state, the cross-sectional area S1 of the positioning hole 11, and the cross-sectional area S2 of the positioning post 3 in the limited state, as shown in Table 1 and Table 2, this embodiment provides ten sets of examples and twelve sets of comparative examples for illustration.

[0077] Table 1

[0078]

[0079] As can be seen from Examples 1 to 10 in Table 1, after meeting the range limitations, the gap between the positioning post 3 and the positioning hole 11 (that is, the difference between the diameter D2 of the positioning hole 11 and the maximum diameter D1 of the positioning post 3 in the assembled state) is appropriate, enabling better assembly and positioning. The positioning post 3 after hot melting can better connect and fix the side plate 2 and the insulating film body 1, reducing the gap between the insulating film body 1 and the side plate 2, and avoiding the electrolyte from corroding the explosion-proof valve and the housing 4.

[0080] Table 2

[0081]

[0082] As can be seen from Comparative Examples 1 and 2 in Table 2, the gap between the positioning post 3 and the positioning hole 11 is too large, resulting in loose assembly and inability to accurately position, reducing the assembly effect.

[0083] As can be seen from Comparative Examples 3 and 4 in Table 2, the gap between the positioning post 3 and the positioning hole 11 is too small, making the assembly difficult and prone to wrinkling, increasing the risk of damage to the insulating film body 1 and the side plate 2 during the assembly process.

[0084] As can be seen from Comparative Examples 5 and 6 in Table 2, the height of the positioning post 3 relative to the insulating film body 1 (that is, the difference between the height H2 of the positioning post 3 in the assembled state and the thickness H1 of the insulating film body 1) is too short, making it difficult to perform hot melting and hard to fix the relative positions of the side plate 2 and the insulating film body 1.

[0085] As can be seen from Comparative Example 7 and Comparative Example 8 in Table 2, the positioning column 3 is too long relative to the insulating film body 1, making hot melting difficult.

[0086] As can be seen from Comparative Example 9 and Comparative Example 10 in Table 2, the proportion area of the positioning hole 11 is too large, and the cross-sectional area S1 of the positioning hole 11 is equivalent to the cross-sectional area after hot melting of the positioning column 3 (that is, the cross-sectional area S2 when the positioning column 3 is in the limit state), making it easy to fall off.

[0087] As can be seen from Comparative Example 11 and Comparative Example 12 in Table 2, the proportion area of the positioning hole 11 is too small, and the cross-sectional area of the positioning column 3 is too large after hot melting, easily causing the insulating film body 1 and the side plate 2 to be affected by too much heat and wrinkle and warp.

[0088] The assembly process of the insulating film assembly is as follows:

[0089] Lay the insulating film body 1 flat, place the side plate 2 above the insulating film body 1, and pass the positioning column 3 through the positioning hole 11 to achieve the preliminary positioning of the side plate 2, so that the side plate 2 is arranged in the middle of the insulating film body 1. Hot melt one end of the positioning column 3 away from the side plate 2, so that the positioning column 3 undergoes a shape change and is converted from the assembly state to the limit state, realizing the assembly of the side plate 2 and the positioning column 3; the insulating film body 1 assembled with the side plate 2 is wrapped on the electrode group, so that the side plate 2 abuts against the bottom surface of the electrode group, and both ends of the insulating film body 1 coincide and are arranged on the top surface of the electrode group, realizing the assembly of the insulating film assembly and the electrode group.

[0090] It should be noted that the height of the positioning column 3 in the limit state can be adjusted according to the height of the positioning column 3 in the assembly state and the control design of the hot melt parameters, which will not be elaborated here.

[0091] Refer to Figure 7 and Figure 8 , the present invention provides a battery, including an electrode group, a housing 4 and an insulating film assembly, and the insulating film body 1 is arranged between the electrode group and the housing 4.

[0092] In this embodiment, an explosion-proof valve is provided on the housing 4, a plurality of through holes 21 are correspondingly opened at the position of the side plate 2 corresponding to the explosion-proof valve, and one end of the positioning column 3 away from the side plate 2 abuts against the bottom surface of the housing 4.

[0093] In this way, the insulating film body 1 and the side plate 2 can be tightly abutted under the action of the positioning column 3, so that the connection part of the insulating film body 1 and the side plate 2 has good sealing performance and connection stability, avoiding the leakage of the electrolyte and corrosion of the housing 4 and the battery cell. Moreover, one end of the positioning column 3 away from the side plate 2 abuts against the housing 4, which can support the electrode group and the insulating film body 1, and form an exhaust channel between the insulating film body 1 and the side plate 2, facilitating the rapid discharge of the gas inside the battery to the explosion-proof valve.

[0094] It can be understood that the overlapping area of the insulating film body 1 can also be located below the side plate 2, as long as stable wrapping of the electrode group can be achieved, and no further elaboration will be made here.

[0095] Obviously, the above-mentioned embodiments of the present invention are merely examples for clearly explaining the present invention, rather than 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 enumerate 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), wherein the insulating film body (1) covers the electrode group arrangement; A side plate (2), wherein the side plate (2) is connected to the insulating film body (1); A positioning column (3), wherein the positioning column (3) is arranged on the side plate (2), and the insulating film body (1) is correspondingly provided with a positioning hole (11) for the positioning column (3) to pass through, and the positioning column (3) has a limiting state, so that when the positioning column (3) is in the limiting state, the side plate (2) and the insulating film body (1) are tightly abutted to limit the relative position of the insulating film body (1) and the side plate (2).

2. The insulating film assembly according to claim 1, characterized in that: Two positioning columns (3) are provided, and the two positioning columns (3) are respectively provided at two ends of the side plate (2), and the positioning holes (11) are provided in a one-to-one correspondence with the positioning columns (3).

3. The insulating film assembly according to claim 1, characterized in that: The positioning column (3) also has an assembled state. When the positioning column (3) is in the assembled state, the cross-sectional area of ​​the end of the positioning column (3) away from the side plate (2) is smaller than the cross-sectional area of ​​the positioning hole (11). When the positioning column (3) is in the limiting state, the cross-sectional area of ​​the end of the positioning column (3) away from the side plate (2) is larger than the cross-sectional area of ​​the positioning hole (11).

4. The insulating film assembly according to claim 3, characterized in that: The thickness of the insulating film body (1) is H1, the height of the positioning column (3) in the assembly state is H2, and 0.30mm≤H2-H1≤0.65mm is satisfied; and / or the maximum diameter of the positioning column (3) in the assembly state is D1, the diameter of the positioning hole (11) is D2, and 0.05mm≤D2-D1≤0.30mm is satisfied.

5. The insulating film assembly according to claim 3, characterized in that: The height of the positioning column (3) when in the limiting state is H3, and satisfies 0.10mm≤H3≤0.15mm; and / or the cross-sectional area of ​​the positioning hole (11) is S1, the cross-sectional area of ​​the positioning column (3) when in the limiting state is S2, and satisfies 14%≤S1 / S2≤84%.

6. The insulating film assembly according to claim 3, characterized in that: When the positioning column (3) is in the assembly state, the positioning column (3) is a truncated cone structure.

7. The insulating film assembly according to any one of claims 1 to 6, characterized in that: The positioning column (3) is made of a plastically deformable material, so that the positioning column (3) can be deformed to form the limiting state.

8. The insulating film assembly according to any one of claims 1 to 6, characterized in that: The positioning column (3) and the side plate (2) are integrally formed.

9. The insulating film assembly according to any one of claims 1 to 6, characterized in that: The side plate (2) is provided with a plurality of through holes (21), and along a symmetry axis in the width direction of the side plate (2), the plurality of through holes (21) are symmetrically arranged.

10. A battery, characterized in that: It comprises a pole group, a shell (4) and an insulating film assembly according to any one of claims 1 to 9, wherein the insulating film body (1) is arranged between the pole group and the shell (4).

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