Insulating film structure and battery cell
By controlling the dimensional difference and pre-folding line design in the cell insulation film structure, the problems of easy wrinkling and scratching of the insulation film are solved, achieving tight bonding and stable fixation, improving the insulation effect and the smoothness of cell insertion into the casing.
Patent Information
- Application Number
- CN202423263106.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-12-16
- Estimated Expiration
- 2034-12-27
AI Technical Summary
The existing battery cell insulation film is relatively soft and thin. If the size design is not reasonable, it is easy to wrinkle and accumulate or be scratched by the shell, which affects the insulation effect and stability.
The insulating film structure is designed such that the distance difference between it and the two ends of the shell in the first direction is 1.5 to 2.0 mm, the inner perimeter of the pattern is smaller than the outer perimeter of the electrode group, and it is divided into multiple overlapping parts by pre-folded lines to ensure tight fit and stable fixation.
This effectively avoids the accumulation and tearing of insulating film wrinkles, improves the fixing stability and insulation of the insulating film, and ensures smooth insertion of battery cells into the casing and high space utilization.
Smart Images
Figure CN223680349U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of battery, in particular to an insulation film structure and a battery cell. BACKGROUND
[0002] At present, the battery cell usually wraps an insulation film on the outside of the pole group to realize the insulation between the pole group and the shell. However, the insulation film used to wrap the pole group at present is usually soft in texture and about 0.1mm in thickness. The length of the battery cell shell is generally 400-650mm or even longer. Once the size of the insulation film is not reasonably designed, if the size is too large, the redundancy will be generated after the insulation film and the lower plastic are hot melted, which makes the insulation film prone to wrinkle accumulation in the process of entering the shell with the pole group, affecting the entering of the shell, and the insulation film is easily scratched by the shell, affecting the insulation effect. If the size is too small, the hot melting size of the insulation film and the lower plastic is insufficient, affecting the stability and insulation of the insulation film. CONTENT OF THE UTILITY MODEL
[0003] The purpose of the present application is to provide an insulation film structure and a battery cell to solve the technical problem in the prior art that the insulation film used to wrap the pole group at present is usually soft in texture and about 0.1mm in thickness. The length of the battery cell shell is generally 400-650mm or even longer. Once the size of the insulation film is not reasonably designed, if the size is too large, the redundancy will be generated after the insulation film and the lower plastic are hot melted, which makes the insulation film prone to wrinkle accumulation in the process of entering the shell with the pole group, affecting the entering of the shell, and the insulation film is easily scratched by the shell, affecting the insulation effect. If the size is too small, the hot melting size of the insulation film and the lower plastic is insufficient, affecting the stability and insulation of the insulation film.
[0004] According to a first aspect of the present application, an insulation film structure for a battery cell is provided, the battery cell comprising a shell and a pole group arranged inside the shell, the shell comprising a shell body and a top cover patch, the shell body being arranged to form a containing space penetrating through the shell along a first direction, and the top cover patch being arranged on both ends of the shell body in the first direction;
[0005] The insulation film structure is arranged at least one turn around the outside of the pole group and between the shell body and the pole group;
[0006] In the first direction, the difference between the distance between the two top cover patches at both ends of the shell body and the size of the insulation film structure in the first direction is 1.5-2.0mm;
[0007] A plane perpendicular to the first direction is defined as a cutting plane, and a figure obtained by cutting both the insulating film structure and the pole group by the cutting plane in a state where the insulating film structure and the pole group are unassembled is defined as a first figure and a second figure, respectively, wherein a length of an inner edge of the first figure is smaller than a length of an outer edge of the second figure.
[0008] Preferably, the pole group is a cuboid, and the pole group includes two narrow edge faces and two large faces, wherein the two narrow edge faces are two end faces of the pole group opposite to each other in a second direction, and the two large faces are two end faces of the pole group opposite to each other in a third direction, the second direction is perpendicular to the third direction, and a plane determined by the second direction and the third direction is parallel to the cutting plane.
[0009] Preferably, the insulating film structure is formed by bending a planar film;
[0010] The planar film is provided with a first pre-folding line, a second pre-folding line, a third pre-folding line and a fourth pre-folding line, all of which extend along the first direction, and are arranged side by side and spaced apart to sequentially divide the planar film into a first part, a second part, a third part, a fourth part and a fifth part;
[0011] At least part of the first part and the fifth part are overlapped, so that the insulating film structure is arranged around the pole group.
[0012] Preferably, in a state where the insulating film structure and the pole group are assembled;
[0013] The overlapped structure formed by the first part and the fifth part is in contact with one of the two narrow edge faces, and the third part is in contact with the other of the two narrow edge faces;
[0014] The second part and the fourth part are in contact with the two large faces, respectively.
[0015] Preferably, in a direction perpendicular to the first direction on the planar film, a size of the overlapped structure and a size of the third part are both equal to A, wherein a difference between a size of the pole group in the third direction and the value of A is 0.5mm-1.0mm.
[0016] Preferably, in a direction perpendicular to the first direction on the planar film, a size of the second part and a size of the fourth part are both equal to B, wherein a difference between the value of B and a size of the pole group in the second direction is 0.4mm-0.7mm.
[0017] Preferably, in a direction perpendicular to the first direction on the planar film, the size of the first part and the size of the fifth part are both equal to C, wherein the difference between the size of the pole group in the third direction and the value of C is 1.0mm-2.0mm.
[0018] According to the second aspect of the present application, an electric core is provided, comprising the above-mentioned shell, the pole group and the insulating film structure of any one of the technical solutions described above, so that the electric core has all the beneficial technical effects of the insulating film structure, which will not be described here again.
[0019] Preferably, the shell further comprises a cover plate and an insulating piece, the cover plate is arranged on both ends of the shell body in the first direction, the top cover patch is arranged on the side of the cover plate facing away from the pole group, and the insulating piece is attached to the side of the cover plate facing the pole group, and at least part of the insulating piece abuts against the end of the pole group in the first direction.
[0020] In the first direction, at least part of the insulating film structure overlaps with the insulating piece.
[0021] Preferably, for one end of the insulating film structure in the first direction, the size of the part of the insulating film structure overlapping with the insulating piece in the first direction is 0.5mm-1mm.
[0022] Compared with the prior art, the present application has the following beneficial effects:
[0023] The insulating film structure provided by the present application has the following beneficial effects: on the one hand, the length of the inner edge of the first graph (i.e. the graph obtained by cutting the insulating film structure with a cutting plane) is less than the length of the outer edge of the second graph (i.e. the graph obtained by cutting the pole group with a cutting plane), not only when the insulating film structure is wrapped around the outside of the pole group, but also when the insulating film structure is tightly attached to the surface of the pole group, effectively preventing the insulating film structure from moving relative to the pole group and reducing the probability of wrinkles accumulating in the insulating film structure; moreover, the insulating film structure can effectively compress the pole group, increasing the gap between the pole group and the shell body and preventing the insulating film structure from being scratched by the shell body; on the other hand, the difference between the distance between the two top cover patches at both ends of the shell body and the size of the insulating film structure in the first direction is controlled to be between 1.5-2.0mm, ensuring that the length of the insulating film structure in the first direction can adapt to the length of the shell, not only effectively preventing the insulating film structure from being too long to cause redundancy at both ends of the insulating film structure in the first direction, but also effectively preventing the insulating film structure from being too short to affect the fixing stability and insulation of the insulating film structure.
[0024] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the following describes a preferred embodiment in detail below, together with the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS
[0025] In order to more clearly illustrate the technical solutions in the specific embodiments or prior art of the present application, the drawings needed to be used in the description of the specific embodiments or prior art will be briefly introduced as follows. Obviously, the drawings described below are some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.
[0026] Figure 1 The structure schematic diagram of the insulating film structure provided by the embodiments of the present application is in an unfolded state.
[0027] Figure 2 The partial structure assembly structure schematic diagram of the battery cell provided by the embodiments of the present application is shown.
[0028] Figure 3 The explosion structure schematic diagram of the battery cell provided by the embodiments of the present application is shown.
[0029] Figure 4 The pole group and insulating film structure assembly schematic diagram provided by the embodiments of the present application is shown.
[0030] Reference signs:
[0031] 1-insulating film structure; 101-first part; 102-second part; 103-third part; 104-fourth part; 105-fifth part; 11-first pre-folding line; 12-second pre-folding line; 13-third pre-folding line; 14-fourth pre-folding line; 2-pole group; 3-top cover patch; 4-insulating piece; 5-cover plate; 6-shell body; 7-outer insulating film.
[0032] F1-first direction; F2-second direction; F3-third direction. DETAILED DESCRIPTION
[0033] The technical solutions of the present application will be described in detail below with reference to the drawings. Obviously, the described embodiments are some embodiments of the present application, not all embodiments of the present application.
[0034] The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the claimed present application, but only represents selected embodiments of the present application.
[0035] Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.
[0036] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.
[0037] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0038] The following refers to Figures 1 to 4 The insulating film structure and the battery cell according to some embodiments of the present application are described.
[0039] Referring to Figures 1 to 4 The embodiments of the first aspect of the present application provide an insulating film structure for a battery cell, the battery cell comprising a shell and a pole group 2 arranged inside the shell, the shell comprising a shell body 6 and a top cover patch 3, the shell body 6 being arranged to form an accommodating space through the shell in a first direction F1, and the top cover patch 3 being arranged at both ends of the shell body 6 in the first direction F1. The insulating film structure 1 is arranged at least one turn around the outside of the pole group 2, and is arranged between the shell body 6 and the pole group 2. In the first direction F1, the distance between the two top cover patches 3 at both ends of the shell body 6 (i.e. Figure 2 The difference between the H value shown) and the size of the insulating film structure 1 in the first direction F1 (i.e. Figure 1 The difference between the H value shown) and the size of the insulating film structure 1 in the first direction F1 (i.e.
[0040] According to the insulation film structure provided by the technical features, on one hand, the length of the inner edge of the first pattern (i.e. the pattern obtained by cutting the insulation film structure 1 with the cutting plane) is smaller than the length of the outer edge of the second pattern (i.e. the pattern obtained by cutting the pole group 2 with the cutting plane), which not only ensures that the insulation film structure 1 can be closely attached to the surface of the pole group 2 when the insulation film structure 1 wraps the outer side of the pole group 2, effectively avoiding the insulation film structure 1 from moving relative to the pole group 2, and reducing the probability of the insulation film structure 1 being wrinkled and accumulated, but also effectively compresses the pole group 2, increases the gap between the pole group 2 and the shell body 6, and avoids the insulation film structure 1 being scratched by the shell body 6. On the other hand, the difference between the distance between the two top cover patches 3 at the two ends of the shell body 6 and the size of the insulation film structure 1 in the first direction F1 is controlled to be between 1.5-2.0 mm, which ensures that the length of the insulation film structure 1 in the first direction F1 can adapt to the length of the shell, not only effectively avoiding the insulation film structure 1 being too long to cause the ends of the insulation film structure 1 in the first direction F1 to be redundant, but also effectively avoiding the insulation film structure 1 being too short to affect the fixing stability and insulation of the insulation film structure 1.
[0041] Preferably, as shown in Figures 1 to 4 The above-mentioned pole group 2 is shown as an example of a cuboid, i.e. an example of a square-shaped battery cell. However, it is not limited thereto, and the insulation film structure 1 provided by the present application is not limited to being applicable to the above-mentioned example of a square-shaped battery cell, but can also be applicable to a cylindrical battery cell or other special-shaped battery cell.
[0042] The insulation film structure 1 will be described in detail below by taking the above-mentioned example of the insulation film structure 1 being applicable to a square-shaped battery cell.
[0043] Correspondingly, as shown in Figure 2 The above-mentioned pole group 2 can include two narrow side faces and two large faces, the two narrow side faces can be two end faces of the pole group 2 opposite to each other in the second direction F2, and the two large faces can be two end faces of the pole group 2 opposite to each other in the third direction F3. The second direction F2 is perpendicular to the third direction F3, and the plane determined by the second direction F2 and the third direction F3 is parallel to the cutting plane. As shown in Figures 1 to 4 The F1 shown in the figure can be an example of the above-mentioned first direction F1, the F2 shown in the figure can be an example of the above-mentioned second direction F2, and the F3 shown in the figure can be an example of the above-mentioned third direction F3.
[0044] Preferably, as shown in Figure 1 The above-mentioned insulation film structure 1 can be formed by bending a planar film, so as to facilitate the storage and transportation of the film material.
[0045] Preferably, as shown in Figure 1As shown, the planar membrane is provided with a first pre-fold line 11, a second pre-fold line 12, a third pre-fold line 13, and a fourth pre-fold line 14, all extending along a first direction F1. These four pre-fold lines 11, 12, 13, and 14 are arranged side-by-side and spaced apart to sequentially divide the planar membrane into a first part 101, a second part 102, a third part 103, a fourth part 104, and a fifth part 105. Figure 4 As shown, at least a portion of the first part 101 and the fifth part 105 overlap so that the insulating film structure 1 is arranged around the electrode group 2.
[0046] Preferably, when the insulating film structure 1 and the electrode assembly 2 are in the assembled state, the overlapping structure formed by the first part 101 and the fifth part 105 is bonded to one of the two narrow side surfaces, and the third part 103 is bonded to the other of the two narrow side surfaces. Correspondingly, the second part 102 and the fourth part 104 are bonded to the two large surfaces respectively. In this way, the seam of the insulating film structure 1 is located on the narrow side surface, which not only ensures the flatness, integrity and smoothness of the part of the insulating film structure 1 bonded to the two large surfaces, so as to reduce the impact of the seam of the insulating film structure 1 on the insulation capability of the electrode assembly 2, but also effectively avoids the influence of the insulating film structure 1 on the dimensions of the cell in the third direction F3.
[0047] Preferably, such as Figure 1 As shown, in the direction perpendicular to the first direction F1 on the planar membrane, the dimensions of the overlapping structure and the third part 103 are both equal to A, wherein the dimensions of the pole group 2 in the third direction F3 (i.e., Figure 2 The difference between the T value and the A value shown is 0.5mm to 1.0mm. In other words, 0.5mm ≤ (TA) ≤ 1.0mm. Thus, the size of the first pattern in the third direction F3 is smaller than the size of the second pattern in the third direction F3. When the insulating film structure 1 is assembled with the electrode group 2, it can effectively compress the size of the assembled electrode group 2 in the third direction F3, thereby making it easier for the assembled electrode group 2 to be inserted into the shell.
[0048] Preferably, such as Figure 1 As shown, in the direction perpendicular to the first direction F1 on the planar membrane, the dimensions of the second part 102 and the fourth part 104 are both equal to B, where the value of B is the same as the dimension of the pole group 2 in the second direction F2 (i.e., Figure 2 The difference between the W values shown is 0.4mm to 0.7mm. In other words, 0.4mm ≤ (BW) ≤ 0.7mm. Thus, the size of the first pattern in the third direction F3 is slightly larger than the size of the second pattern in the third direction F3, so as to compensate for the size difference between the size of the first pattern in the third direction F3 and the size of the second pattern in the third direction F3, thereby facilitating the assembly of the electrode group 2 and the insulating film structure 1.
[0049] Correspondingly, by setting the dimensions of the first pattern in the second direction F2 and the third direction F3 in the manner described above, the gap between the shell body 6 and the assembled pole assembly 2 can be between 0.4mm and 0.7mm. This not only effectively ensures the smooth insertion of the pole assembly 2 into the shell, but also ensures the space utilization rate of the pole assembly 2 on the shell body 6.
[0050] It should be noted that the insulating film structure 1 is usually an insulating plastic film with a certain degree of elasticity, while the pole group 2 is usually a laminated pole group or a wound pole group. Whether it is a laminated pole group or a wound pole group, there is a certain compression space inside. Therefore, even if the perimeter of the inner edge of the first pattern is smaller than the perimeter of the outer edge of the second pattern, the insulating film structure 1 can still wrap around the outside of the pole group 2.
[0051] Preferably, such as Figure 1 As shown, in the direction perpendicular to the first direction F1 on the planar membrane, the dimensions of the first part 101 and the fifth part 105 are both equal to C. The difference between the dimension of the electrode group 2 in the third direction F3 and the value of C is 1.0mm to 2.0mm. In other words, 1.0mm ≤ (TC) ≤ 2.0mm. Thus, while ensuring the conservation of planar membrane material, it is possible not only to ensure that the overlapping structure formed by the first part 101 and the fifth part 105 can meet the above-mentioned dimensional requirements, but also to ensure that the overlapping parts of the first part 101 and the fifth part 105 have sufficient connection space.
[0052] Optionally, the first part 101 and the fifth part 105 mentioned above can be joined by heat fusion.
[0053] Refer to Table 1, which shows the assembly results of the electrode assembly 2 and the insulating film structure 1 of the same size, which are respectively assembled into the same shell body 6.
[0054] Table 1:
[0055]
[0056] As shown in Table 1, when the insulating film structure 1 satisfies 1.5mm≤(HD)≤2.0mm and 0.5mm≤(TA)≤1.0mm, 0.4mm≤(BW)≤0.7mm, and 1.0mm≤(TC)≤2.0mm, it can ensure that the electrode group 2 can be smoothly inserted into the shell and the insulating film structure 1 can be well fixed without abnormal wrinkles or stacking, and there is no mutual interference between the insulating film structure 1 and the shell body 6.
[0057] See Figures 2 to 4The embodiments of the second aspect of the application also provide an electric core comprising the insulation film structure of any of the above embodiments, thus having all the beneficial technical effects of the insulation film structure, which will not be repeated here.
[0058] Preferably, as shown in the figure, the shell can further comprise a cover plate 5 covering both ends of the shell body 6 in the first direction F1 to form a closed space with the shell body 6 to accommodate both the pole group 2 and the insulation film structure 1. The top cover patch 3 is covered on the side of the cover plate 5 facing away from the pole group 2. Figures 2 to 4 Preferably, as shown in the figure, the shell can further comprise an insulation piece 4 attached to the side of the cover plate 5 facing the pole group 2, and at least part of the insulation piece 4 abuts the end of the pole group 2 in the first direction F1, on the one hand, to achieve insulation between the cover plate 5 and the pole group 2; on the other hand, through the abutting action of the insulation piece 4 and the pole group 2, the position of the pole group 2 in the first direction F1 within the shell body 6 can be effectively limited, preventing the pole group 2 from moving within the shell body 6 and ensuring the stability of the electric core.
[0059] Figures 2 to 4 Preferably, as shown in the figure, in the first direction F1, at least part of the insulation film structure 1 overlaps the pole group 2 and the insulation piece 4, so that through the overlapping cooperation of the insulation film structure 1 and the insulation piece 4, the integrity of the insulation of the pole group 2 can be effectively ensured.
[0060] Preferably, as shown in the figure, for one end of the insulation film structure 1 in the first direction F1, the size of the overlapping part of the insulation film structure 1 and the insulation piece 4 in the first direction F1 is 0.5mm-1mm, so on the one hand, it ensures that the overlapping part can have enough space for the heat fusion connection of the insulation piece 4 and the insulation film structure 1; on the other hand, based on 1.5mm≤(H-D)≤2.0mm, both ends of the top cover patch 3 and the insulation film structure 1 in the first direction F1 of the electric core can be provided with anti-piling gaps, and the size of the anti-piling gap in the first direction F1 (i.e. the f value shown in the figure) is 0.5mm-1.0mm, in other words, 0.5mm≤f≤1.0mm, to further prevent the insulation film structure 1 from piling up and folding during the process of entering the shell along the first direction F1. Figure 4 Preferably, as shown in the figure, the shell can further comprise an insulation piece 4 attached to the side of the cover plate 5 facing the pole group 2, and at least part of the insulation piece 4 abuts the end of the pole group 2 in the first direction F1, on the one hand, to achieve insulation between the cover plate 5 and the pole group 2; on the other hand, through the abutting action of the insulation piece 4 and the pole group 2, the position of the pole group 2 in the first direction F1 within the shell body 6 can be effectively limited, preventing the pole group 2 from moving within the shell body 6 and ensuring the stability of the electric core.
[0061] Figure 4 Preferably, as shown in the figure, in the first direction F1, at least part of the insulation film structure 1 overlaps the pole group 2 and the insulation piece 4, so that through the overlapping cooperation of the insulation film structure 1 and the insulation piece 4, the integrity of the insulation of the pole group 2 can be effectively ensured. Figure 4 Preferably, as shown in the figure, for one end of the insulation film structure 1 in the first direction F1, the size of the overlapping part of the insulation film structure 1 and the insulation piece 4 in the first direction F1 is 0.5mm-1mm, so on the one hand, it ensures that the overlapping part can have enough space for the heat fusion connection of the insulation piece 4 and the insulation film structure 1; on the other hand, based on 1.5mm≤(H-D)≤2.0mm, both ends of the top cover patch 3 and the insulation film structure 1 in the first direction F1 of the electric core can be provided with anti-piling gaps, and the size of the anti-piling gap in the first direction F1 (i.e. the f value shown in the figure) is 0.5mm-1.0mm, in other words, 0.5mm≤f≤1.0mm, to further prevent the insulation film structure 1 from piling up and folding during the process of entering the shell along the first direction F1.
[0062] Figure 3 Preferably, as shown in the figure, the shell can further comprise an insulation piece 4 attached to the side of the cover plate 5 facing the pole group 2, and at least part of the insulation piece 4 abuts the end of the pole group 2 in the first direction F1, on the one hand, to achieve insulation between the cover plate 5 and the pole group 2; on the other hand, through the abutting action of the insulation piece 4 and the pole group 2, the position of the pole group 2 in the first direction F1 within the shell body 6 can be effectively limited, preventing the pole group 2 from moving within the shell body 6 and ensuring the stability of the electric core.
[0063] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. An insulating film structure, characterized by, The application relates to an insulation film structure for an electric core, wherein the electric core comprises a shell and a pole group arranged inside the shell, the shell comprises a shell body and top cover patches, the shell body is arranged to form a containing space penetrating through the shell along a first direction, and the top cover patches are respectively arranged on both ends of the shell body in the first direction. The insulation film structure is arranged at least one round outside the pole group and between the shell body and the pole group. In the first direction, the distance between the two top cover patches on both ends of the shell body and the size of the insulation film structure in the first direction are different by 1.5-2.0 mm. A plane perpendicular to the first direction is defined as a cutting plane, and the figures obtained by cutting the insulation film structure and the pole group by the cutting plane are respectively defined as a first figure and a second figure when the insulation film structure and the pole group are in an unassembled state, wherein the circumference of the inner edge of the first figure is smaller than the circumference of the outer edge of the second figure.
2. The insulation film structure according to claim 1, wherein the pole group is a cuboid, the pole group comprises two narrow edge faces and two large faces, the two narrow edge faces are two end faces of the pole group opposite to each other in a second direction, the two large faces are two end faces of the pole group opposite to each other in a third direction, the second direction is perpendicular to the third direction, and the plane determined by the second direction and the third direction is parallel to the cutting plane.
3. The insulating film structure of claim 2, wherein the insulation film structure is formed by bending a plane film; the plane film is provided with a first pre-folding line, a second pre-folding line, a third pre-folding line and a fourth pre-folding line all extending along the first direction, the first pre-folding line, the second pre-folding line, the third pre-folding line and the fourth pre-folding line are arranged side by side and spaced apart to sequentially divide the plane film into a first part, a second part, a third part, a fourth part and a fifth part; at least part of the first part and the fifth part are overlapped to arrange the insulation film structure around the pole group for one round.
4. The insulation film structure according to claim 3, wherein when the insulation film structure and the pole group are in an assembled state, the overlapped structure formed by the first part and the fifth part is attached to one of the two narrow edge faces, the third part is attached to the other of the two narrow edge faces; and the second part and the fourth part are respectively attached to the two large faces.
5. The insulating film structure of claim 4, wherein In a direction perpendicular to the first direction on the plane film, the size of the overlapped structure and the size of the third part are both equal to A, wherein the difference between the size of the pole group in the third direction and the value of A is 0.5-1.0 mm.
6. The insulating film structure of claim 4, wherein In a direction perpendicular to the first direction on the plane film, the size of the second part and the size of the fourth part are both equal to B, wherein the difference between the value of B and the size of the pole group in the second direction is 0.4-0.7 mm.
7. The insulating film structure of claim 4, wherein In a direction perpendicular to the first direction on the planar film, the size of the first portion and the size of the fifth portion are each equal to C, wherein the difference between the size of the pole group in the third direction and the value of C is 1.0 mm to 2.0 mm.
8. An electric cell characterized by The structure includes the housing, the pole group, and the insulating film according to any one of claims 1 to 7.
9. The electric cell of claim 8, wherein, The housing further includes a cover plate and an insulating member, the cover plate is provided on both ends of the housing body in the first direction, the top cover patch is provided on the side of the cover plate facing away from the pole group, and the insulating member is attached to the side of the cover plate facing the pole group, at least part of the insulating member abuts against the end of the pole group in the first direction; In the first direction, at least part of the insulating film structure overlaps with the insulating member.
10. The electric cell of claim 9, wherein, For one end of the insulating film structure in the first direction, the size of the overlapping part of the insulating film structure and the insulating member in the first direction is 0.5 mm to 1 mm.