Insulation protective film, bare cells, batteries and battery packs

Abstract

The present application provides an insulating protective film, a bare cell, a battery and a battery pack, and relates to the field of battery technology. According to the insulating protective film provided by the present application, the bottom, the side in the length direction, the side in the width direction and the top of the pole group can be coated, so as to form insulating protection for the pole group. According to the insulating protective film provided by the embodiment of the present application, the size of the third part in the width direction is G, and the margin of the pole ear of the pole group is H, 20%≤G / H≤90%, which is conducive to making the pole group part outside the pole ear exposed as small as possible, improving the insulation performance of the pole group covered by the insulating protective film, and preventing the pole piece located outside the pole ear from being crushed during assembly, and also avoiding the interference between the insulating film and the pole ear, affecting the subsequent ultrasonic welding of the pole ear, and avoiding the tearing of the pole ear.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to an insulating protective film, a bare cell, a battery and a battery pack. Background Art

[0002] In the production process of bare battery cells, an insulating protective film is usually used to coat the electrode group to protect the electrode group and ensure the insulation performance of the electrode group. However, current technology lacks a unified coating method for the electrode group, so there is still room for improvement. Summary of the invention

[0003] In view of this, the present application provides an insulating protective film, a bare cell, a battery and a battery pack, the purpose of which is to solve the above technical problems to a certain extent.

[0004] A first aspect of an embodiment of the present application provides an insulating protective film, the insulating protective film is used to cover an electrode group, the electrode group has an electrode ear located at the top, the electrode group also has a length direction and a width direction, the insulating protective film includes:

[0005] A bottom portion, the bottom portion being used to cover the bottom portion of the electrode group;

[0006] Two first areas, the two first areas are respectively located at two sides of the bottom in the width direction;

[0007] The first region includes a first portion and two second portions, the first portion is connected to the side of the bottom in the width direction, the two second portions are respectively connected to the two sides of the first portion in the length direction, and the first region further includes a third portion corresponding to each second portion, the third portion is connected to the side of the corresponding second portion away from the bottom in the width direction;

[0008] The first portion is used to cover the side of the electrode group in the width direction, the second portion is used to cover the side of the electrode group in the length direction, and the third portion is used to cover the top of the electrode group;

[0009] The dimension of the third portion in the width direction is G, the distance between the pole lug of the pole group and the side of the pole group in the length direction is the margin H of the pole lug, and 20%≤G / H≤90%.

[0010] Preferably, 60%≤G / H≤80%, the insulating protection film further includes two second regions, and the two second regions are respectively located at two sides of the bottom in the length direction.

[0011] Preferably, the first region further includes a fourth portion, the fourth portion being connected to a side of the first portion in the width direction away from the bottom.

[0012] The fourth portion has two first inclined sides opposite to each other in the length direction, and an included angle A2 between the first inclined sides and the side of the first portion in the width direction satisfies 30°≤A2≤150°;

[0013] And / or, the third portion has a second inclined side portion close to the first inclined side portion in the length direction, and an included angle A1 between the second inclined side portion and a side portion of the third portion close to the second portion satisfies 30°≤A1≤150°.

[0014] Preferably, the first region further includes a fourth portion, the fourth portion is connected to a side of the first portion in the width direction away from the bottom, and a size of the fourth portion in the width direction is E;

[0015] Wherein, the pole group is a wound pole group, the thickness of a single wound pole group is D1, the insulating protective film is used to cover the wound pole group, 3 mm≤E≤0.5D1-3 mm.

[0016] Preferably, the dimension of the second portion in the length direction is F, the pole group is a wound pole group, the thickness of a single wound pole group is D1, 0.5ND1+3 mm≤F≤ND1 mm, wherein N is the number of the wound pole groups.

[0017] Preferably, the first region further includes a fourth portion, the fourth portion is connected to a side of the first portion in the width direction away from the bottom, and a size of the fourth portion in the width direction is E;

[0018] Wherein, the pole group is a laminated pole group, the thickness of a single laminated pole group is B3, the insulating protective film is used to cover a single laminated pole group, 3 mm≤E≤0.4B3 mm, or the insulating protective film is used to cover two laminated pole groups, 3 mm≤E≤0.75B3 mm.

[0019] Preferably, the dimension of the second portion in the length direction is F, the pole group is a laminated pole group, the thickness of a single laminated pole group is B3, 0.5NB3+3 mm≤F≤NB3 mm, wherein N is the number of the laminated pole groups.

[0020] A second aspect of an embodiment of the present application provides a bare battery cell, which includes the insulating protective film as described above.

[0021] A third aspect of an embodiment of the present application provides a battery, comprising the bare battery cell as described above.

[0022] A fourth aspect of an embodiment of the present application provides a battery pack, comprising a plurality of batteries as described above.

[0023] In this way, according to the insulating protective film provided in the embodiment of the present application, the bottom, the sides in the length direction, the sides in the width direction and the top of the pole group can be covered, so as to form insulating protection for the pole group. According to the insulating protective film provided in the embodiment of the present application, the dimension of the third part in the width direction is G, and the margin of the pole ear of the pole group is H, 20%≤G / H≤90%, which is conducive to exposing the portion of the pole group outside the pole ear as small as possible, improving the insulation performance of the pole group covered by the insulating protective film, and preventing the pole piece located outside the pole ear from being crushed during assembly, and also avoiding interference between the insulating film and the pole ear, affecting the subsequent ultrasonic welding of the pole ear, and avoiding tearing of the pole ear.

[0024] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are specifically cited below and described in detail with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A schematic diagram of an insulating film provided according to an embodiment of the present application is shown;

[0027] Figure 2 Another schematic diagram of an insulating film provided according to an embodiment of the present application is shown;

[0028] Figure 3 A schematic diagram showing an example of multiple pole groups provided according to an embodiment of the present application;

[0029] Figure 4 A schematic diagram showing an example of a single pole group provided according to an embodiment of the present application;

[0030] Figure 5 A schematic diagram showing another example of a single pole group provided according to an embodiment of the present application;

[0031] Figure 6 A schematic diagram showing another example of multiple pole groups provided according to an embodiment of the present application is shown.

[0032] Reference numerals:

[0033] 100 - insulating protective film; 110 - bottom; 111 - first region; 112 - first part; 113 - second part; 114 - third part; 115 - fourth part; 116 - second region; 120 - notch; 200 - pole group; 210 - pole ear; 300 - length direction; 400 - width direction. DETAILED DESCRIPTION

[0034] The technical solution of the present application will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0035] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, 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, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0036] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0037] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0038] According to a first aspect of an embodiment of the present application, an insulating protective film 100 is provided. Figures 1 to 6 The structure and working principle of the insulating protection film 100 are described in detail.

[0039] According to the insulating protective film 100 provided in the embodiment of the present application, the insulating protective film 100 is used to cover the electrode group 200, the electrode group 200 has a pole ear 210 located at the top, the electrode group 200 also has a length direction 300 and a width direction 400, and the insulating protective film 100 includes a bottom 110 and two first regions 111. In the embodiment, the bottom 110 is used to cover the bottom 110 of the electrode group 200, and the two first regions 111 are respectively located on both sides of the bottom 110 in the width direction 400.

[0040] In the embodiment, the first region 111 includes a first portion 112 and two second portions 113, the first portion 112 is connected to the side of the bottom 110 in the width direction 400, the two second portions 113 are respectively connected to the two sides of the first portion 112 in the length direction 300, and the first region 111 further includes a third portion 114 provided corresponding to each second portion 113, the third portion 114 is connected to the side of the corresponding second portion 113 away from the bottom 110 in the width direction 400. In the embodiment, the first portion 112 is used to cover the side of the pole group 200 in the width direction 400, the second portion 113 is used to cover the side of the pole group 200 in the length direction 300, and the third portion 114 is used to cover the top of the pole group 200.

[0041] In the embodiment, the dimension of the third portion 114 in the width direction 400 is G, the distance between the pole tab 210 of the pole group 200 and the side of the pole group 200 in the length direction 300 is the margin H of the pole tab 210 , and 20%≤G / H≤90%.

[0042] In this way, according to the insulating protection film 100 provided in the embodiment of the present application, the bottom 110, the side in the length direction 300, the side in the width direction 400 and the top of the pole group 200 can be covered, so as to form insulation protection for the pole group 200. According to the insulating protection film 100 provided in the embodiment of the present application, the size of the third part 114 in the width direction 400 is G, and the margin of the pole ear 210 of the pole group 200 is H, 20%≤G / H≤90%, which is conducive to making the part of the pole group 200 outside the pole ear 210 exposed as small as possible, improving the insulation performance of the pole group 200 covered by the insulating protection film 100, and preventing the pole piece located outside the pole ear 210 from being crushed during assembly, and also avoiding interference between the insulating film and the pole ear 210, affecting the subsequent ultrasonic welding of the pole ear 210, and avoiding tearing of the pole ear 210.

[0043] Based on the above description, the following Table 1 lists 15% and 95% outside the above G / H range as comparative examples, lists multiple examples within the above G / H range as embodiments, and annotates the application results corresponding to each example in Table 1.

[0044]

[0045] like Figure 1 As shown, Figure 1 1 shows a schematic diagram of the insulating protective film 100, which essentially shows a plan view of the insulating protective film 100. In the embodiment, Figure 1 It can be understood as a view obtained by observing the insulating protective film 100 along the height direction of the electrode group 200. In this view, the insulating protective film 100 is observed in the "unfolded" state, that is, the state that it has not yet been coated on the electrode group 200. In the subsequent description of the embodiment of the present application, unless it is clearly stated that the insulating protective film 100 is coated on the electrode group 200, the remaining descriptions of the orientation refer to Figure 1 Examples in .

[0046] Continue to refer Figure 2 , Figure 2 Shown with Figure 1 The insulating protective film 100 is shown in FIG. Figure 2 In the embodiment, the markings of specific regions and parts are not shown in detail, but the boundaries between the regions and parts are shown. Figure 1 See also Figure 2 Different regions and different parts within the regions may be divided by the notches 120. For example, the bottom 110 and the first regions 111 connected to both sides of the bottom 110 in the width direction 400 are divided by the notches 120 along the length direction 300. Different parts within the first region 111, for example, the first part 112 and the second part 113 and the second part 113 and the third part 114 may be divided by the notches 120.

[0047] In the embodiment, the “notch 120” is essentially a “fold” between different regions and different parts. After the insulating protective film 100 is coated on the electrode group 200, the position corresponding to the notch 120 is exactly the “edge” of the electrode group 200. The “edge” referred to here is not limited to the edge of the rectangular structure, but should also be broadly understood as the intersection of adjacent side portions of the electrode group 200.

[0048] In the embodiment, the notch 120 is located between different regions and between different parts. Compared with the regions or parts on both sides of the notch 120, the notch 120 may have a smaller thickness, so that one region can rotate relative to another region to achieve the purpose of coating the surface of the electrode group 200. In the embodiment, the smaller thickness of the notch 120 can be obtained by carving the insulating protection film 100. In other words, the notch 120 can be carved on the insulating protection film 100.

[0049] In other examples, the insulating protective film 100 can be repeatedly folded to produce the same Figure 1 and Figure 2 For the creases at the same position in the middle, it can also be understood that, through repeated folding, the thickness at the position where the crease is located is actually still smaller than the thickness of the areas or parts on both sides thereof.

[0050] In the embodiment, as an example, both ends of each notch 120 may not be flush with the outer edge of the insulating protection film 100, or in other words, both ends of each notch 120 are located at the outer edge of the insulating protection film 100. Figure 2 , and combined with Figure 1 Taking the first region 111 and the bottom 110 as an example, the notch 120 extending along the length direction 300 divides the two. However, both ends of the notch 120 in the length direction 300 do not reach the edge of the insulating protection film 100 .

[0051] Therefore, in the embodiment, the setting of the notch 120 in the insulating protective film 100 is equivalent to "hiding" the notch 120. The advantage of this setting method is that, since the thickness of the notch 120 is relatively small, hiding the notch 120 is conducive to avoiding the situation in which, when pulling occurs between different areas or parts during the coating process, different areas or parts of the insulating protective film 100 are torn from the end of the notch 120 at the outer edge of the insulating protective film 100 to the inside of the insulating protective film 100, causing damage to the insulating protective film 100, resulting in failure of the insulating protective film 100 to protect the electrode group 200.

[0052] like Figure 1 As shown, in an embodiment, the bottom 110 and the first portion 112 of the first region 111 may both be rectangular. In an embodiment, the first portion 112 of the first region 111 is connected to the long side of the bottom 110. As an example, the first portion 112 may be the same length as the long side of the bottom 110. Also as an example, the second portion 113, the third portion 114, and the fourth portion 115 to be described later and the second region 116 may all be trapezoidal or substantially trapezoidal.

[0053] As an example, the second portion 113 and the third portion 114 may both be, for example, approximately right-angled trapezoids. A bottom side of the second portion 113 is connected to the wide side of the first portion 112, and a right-angled side of the second portion 113 may be connected to a bottom side of the third portion 114. The “approximately right-angled trapezoid” mentioned here should be understood as the second portion 113 and the third portion 114 being generally in the shape of a right-angled trapezoid, because in actual applications, the corners of the second portion 113 and the third portion 114 may be, for example, formed into a rounded shape, so that the second portion 113 and the third portion 114 are not “right-angled trapezoids” in a strict sense.

[0054] In the embodiment, according to the above description, combined with Figure 1 The dimension of the third portion 114 in the width direction 400 is substantially the height of the third portion 114 which is a substantially right-angled trapezoid. Figure 1 It has been specifically shown in.

[0055] In the embodiment, when the third portion 114 covers the top of the electrode group 200, it covers the top of the electrode group 200 from one side of the top of the electrode group 200 in the width direction 400, that is, the third portion 114 is away from the edge of the second portion 113, that is, the narrower bottom edge eventually faces the electrode ear 210 (see Figures 3 to 6 ).

[0056] In the embodiment, G / H is essentially the percentage of the height of the third portion 114 to the margin of the pole ear 210. If it is less than 20%, the insulating protective film 100 does not adequately cover the pole group 200. The so-called "outside" of the pole ear 210 is the side of the pole ear 210 that is away from the other pole ear 210 in the length direction 300. Due to insufficient coverage, the pole piece of the pole group 200 on this side will be exposed too much, resulting in insufficient insulation protection of the pole piece and possible subsequent pressure damage to the pole piece. If it is greater than 90%, the coating is too much, which may cause interference with the pole ear 210.

[0057] In addition, as an example, in the embodiment, the insulating protective film 100 can be, for example, a Mylar film, and after being coated on the electrode group 200, the insulating protective film 100 can be attached to the outside of the electrode group 200 by means of an adhesive tape. In addition, in the embodiment, although its interpretation has been widely understood, it is still necessary to explain that the electrode group 200 should be understood as including a component formed by a pole piece and a diaphragm, and the pole ear 210 extends outward from the pole piece. Therefore, it can be understood that after the insulating protective film 100 is coated on the outside of the electrode group 200, the two together substantially form a bare battery cell.

[0058] According to the insulating protective film 100 provided in the embodiment of the present application, further, the value range of G / H can be preferably, for example, 60%≤G / H≤80%. Within this preferred range, the amount of the insulating protective film 100 is taken into account, that is, when the third part 114 of a suitable size is set, the area of ​​the third part 114 is not increased too much, and the situation of over-coating and under-coating can be avoided. As an example, G / H can be, for example, any value between 60% and 80% with an integer before the percent sign.

[0059] In addition, the insulating protective film 100 may also include two second regions 116, and the two second regions 116 are respectively located on both sides of the bottom 110 in the length direction 300. As an example, the two second regions 116 and the fourth part 115 to be described later can be formed, for example, into a roughly isosceles trapezoid (still not an isosceles trapezoid in a strict sense due to the setting of the rounded corners), and the bottom edge of the second region 116 can be connected to the wide side of the bottom 110.

[0060] According to the insulating protective film 100 provided in the embodiment of the present application, the first region 111 may further include a fourth portion 115, which may be connected to the side of the first portion 112 away from the bottom 110 in the width direction 400, and the fourth portion 115 has two first inclined sides opposite to each other in the length direction 300 (that is, the two waists of the isosceles trapezoid mentioned in the above description), and the angle A2 between the first inclined side and the side of the first portion 112 in the width direction 400 may satisfy 30°≤A2≤150°. As an alternative or simultaneously, the third portion 114 may have a second inclined side close to the first inclined side in the length direction 300 (that is, the inclined waist of the right-angled trapezoid as above), and the angle A1 between the second inclined side and the side of the third portion 114 close to the second portion 113 satisfies 30°≤A1≤150°. That is, 30°≤A2≤150° and / or, 30°≤A1≤150°.

[0061] In the embodiment, the angles A1 and A2 are in the above angle ranges, which can ensure that the third portion 114 and the fourth portion 115 form an overlapping area after being wrapped together on the top of the electrode group 200, thereby effectively protecting the electrode group 200, more specifically, effectively protecting the electrode sheet in the electrode group 200. In the embodiment, the preferred angle range of A1 and A2 can be, for example, 80°≤A1≤120°, and can specifically be any integer angle value within the range.

[0062] According to the insulating protective film 100 provided in the embodiment of the present application, the size of the fourth portion 115 in the width direction 400 is E, that is, the height of the fourth portion 115 as a substantially isosceles trapezoid is E. In the embodiment, the electrode group 200 may be, for example, a wound electrode group, and the thickness of a single wound electrode group is D1. The insulating protective film 100 is used to cover the wound electrode group (for example Figure 3 A single pole group 200 represented by two wound pole groups is shown in FIG. Figure 4 For the single pole group 200 shown in FIG. 1 ), 3 mm≤E≤0.5D1-3 mm.

[0063] In an embodiment, Figure 4 As shown, Figure 4A schematic diagram showing a three-dimensional view of a single wound pole group. Figure 1 In the embodiment, the value of D1 can be, for example, 10 mm to 100 mm. In the embodiment, the purpose of E being greater than or equal to 3 mm is that 3 mm is the minimum size of the fourth portion 115 that can cover the top of the pole group 200, and is also the minimum size of the insulating protective film 100 and other components in the subsequent process. The upper limit of E is 0.5D1-3 mm to prevent the insulating protective film 100 from pressing on the pole ear 210, causing the pole ear 210 to be inserted into the pole group 200, resulting in a short circuit.

[0064] According to the insulating protection film 100 provided in the embodiment of the present application, the size of the second portion 113 in the length direction 300 is F, 0.5ND1+3 mm≤F≤ND1 mm, where N is the number of wound pole groups.

[0065] Thus, according to the insulating protective film 100 provided in the embodiment of the present application, after the insulating protective film 100 covers the pole group 200, the second portion 113 is located at the two sides of the pole group 200 in the length direction 300, and the two second portions 113 opposite to each other in the width direction 400 are wider than half of the width formed by the entire wound pole group, so that the two corresponding second portions 113 can be folded to form an overlapping protection area, thereby better improving the insulation performance of the pole group 200. Here, the lower limit value of F exceeds half of the number of wound pole groups by 3 mm, which is the minimum value for forming an effective overlapping protection area, and the upper limit value of F can obviously be the same as the width of the entire wound pole group.

[0066] According to the above description, different examples of the thickness D1 of the wound pole group, the dimension F of the second portion 113 in the length direction 300 and the number of pole groups 200 are specifically given in Table 2 below.

[0067]

[0068] According to the insulating protective film 100 provided in the embodiment of the present application, the electrode group 200 may also be, for example, a laminated electrode group (for example Figure 5 and Figure 6 The thickness of a single laminated pole group is B3, and the insulating protective film 100 is used to cover the single laminated pole group, 3 mm≤E≤0.4B3 mm.

[0069] In the embodiment, since the tabs 210 of the laminated pole group are twice as many as those of the wound pole group, the tabs 210 of the wound pole group are actually larger than those of the wound pole group, so the upper limit of E is 0.4B3, where the value range of B3 can also be, for example, 10 mm to 100 mm.

[0070] According to the insulating protective film 100 provided in the embodiment of the present application, the insulating protective film 100 can also be used to cover two laminated pole groups, 3 mm≤E≤0.75B3 mm.

[0071] Furthermore, for the laminated pole group, F can satisfy 0.5NB3+3 mm≤F≤NB3 mm, where N is the number of laminated pole groups. This is similar to the case of the above wound pole group. The purpose of taking the value of F is the same as described above and will not be repeated here.

[0072] According to the above description, different examples of the thickness B3 of the laminated pole group, the dimension F of the second portion 113 in the length direction 300 and the number of pole groups 200 are specifically given in Table 3 below.

[0073]

[0074] According to a second aspect of an embodiment of the present application, a bare battery cell is provided. The bare battery cell includes the above insulating protective film 100 and the above pole group 200. The pole group 200 is coated by the insulating protective film 100 to form the bare battery cell.

[0075] According to a third aspect of an embodiment of the present application, a bare cell is provided. The battery includes the bare cell as above and may further include a shell. The bare cell may be loaded into the shell to form a battery.

[0076] According to a fourth aspect of an embodiment of the present application, a battery pack is provided. The battery pack includes a plurality of batteries as described above and may further include a box. The plurality of batteries as described above are arranged in the box to form a battery module.

[0077] The above are only preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. All equivalent structural changes made by using the contents of the present application specification and drawings under the innovative concept of the present application, or directly / indirectly applied in other related technical fields are included in the protection scope of the present application.

Claims

1. An insulating protective film, characterized in that: The insulating protective film is used to cover the electrode group, the electrode group has a pole ear located at the top, the electrode group also has a length direction and a width direction, and the insulating protective film includes: A bottom portion, the bottom portion being used to cover the bottom portion of the electrode group; Two first areas, the two first areas are respectively located at two sides of the bottom in the width direction; The first region includes a first portion and two second portions, the first portion is connected to the side of the bottom in the width direction, the two second portions are respectively connected to the two sides of the first portion in the length direction, and the first region further includes a third portion corresponding to each second portion, the third portion is connected to the side of the corresponding second portion away from the bottom in the width direction; The first portion is used to cover the side of the electrode group in the width direction, the second portion is used to cover the side of the electrode group in the length direction, and the third portion is used to cover the top of the electrode group; The dimension of the third portion in the width direction is G, the distance between the pole ear of the pole group and the side of the pole group in the length direction is the margin H of the pole ear, 20%≤G / H≤90%; The dimension of the second portion in the length direction is greater than half of the thickness of a single pole group; The first region further includes a fourth portion connected to a side of the first portion in the width direction away from the bottom. The fourth portion has two first inclined sides opposite to each other in the length direction, and an included angle A2 between the first inclined sides and the side of the first portion in the width direction satisfies 30°≤A2≤150°; And / or, the third portion has a second inclined side portion close to the first inclined side portion in the length direction, and an included angle A1 between the second inclined side portion and a side portion of the third portion close to the second portion satisfies 30°≤A1≤150°; Each of the fourth parts and the adjacent third part are wrapped to the top of the pole group to form an overlapping area; The two fourth parts and the two third parts respectively included in the two first regions are coated on the top of the electrode group to form an avoidance region for avoiding the electrode ear.

2. The insulating protective film according to claim 1, characterized in that: 60%≤G / H≤80%, the insulating protection film further includes two second regions, and the two second regions are respectively located on both sides of the bottom in the length direction.

3. The insulating protective film according to claim 1, characterized in that: The dimension of the fourth portion in the width direction is E; Wherein, the pole group is a wound pole group, the thickness of a single wound pole group is D1, the insulating protective film is used to cover the wound pole group, 3 mm≤E≤0.5D1-3 mm.

4. The insulating protective film according to any one of claims 1 to 3, characterized in that: The dimension of the second portion in the length direction is F, the pole group is a wound pole group, the thickness of a single wound pole group is D1, 0.5ND1+3 mm≤F≤ND1 mm, wherein N is the number of the wound pole groups.

5. The insulating protective film according to claim 1, characterized in that: The dimension of the fourth portion in the width direction is E; Wherein, the pole group is a laminated pole group, and the thickness of a single laminated pole group is B3; The insulating protective film is used to cover a single laminated pole group, 3 mm≤E≤0.4B3 mm, or the insulating protective film is used to cover two laminated pole groups, 3 mm≤E≤0.75B3 mm.

6. The insulating protective film according to any one of claims 1, 2 and 5, characterized in that: The dimension of the second part in the length direction is F, the pole group is a laminated pole group, the thickness of a single laminated pole group is B3, 0.5NB3+3mm≤F≤NB3 mm, wherein N is the number of the laminated pole groups.

7. A bare battery cell, characterized in that: The bare battery cell comprises the insulating protective film as claimed in any one of claims 1 to 6.

8. A battery, characterized in that: The battery comprises a bare cell as described in claim 7.

9. A battery pack, characterized in that: The battery pack comprises a plurality of batteries as claimed in claim 8.

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