Battery cell and soft package battery

Abstract

The utility model discloses a battery cell and a soft package battery, which are applied to the technical field of batteries, the battery cell comprises a packaging film shell and an inner core, and at least one side of the packaging film shell is provided with a punching pit; the inner core is arranged in the scouring pit; the surface, close to the punching pit, of the inner core is provided with protective gummed paper, and the protective gummed paper covers at least one area, corresponding to the punching pit fillet of the punching pit, of the inner core. According to the utility model, the protective gummed paper is arranged in the corresponding areas of the inner core and the punched-pit fillet of the packaging film shell, so that the overall safety of the battery cell is improved, and the battery cell is prevented from being directly contacted with the punched-pit fillet of the packaging film shell after being expanded after multiple cycles, thereby reducing the risk of corner cracking and improving the production efficiency. Therefore, energy density reduction caused by improvement measures such as membrane shell space increase is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and particularly relates to a battery cell and a soft-pack battery. Background Art

[0002] A soft-pack battery is composed of an outer packaging film shell that wraps and seals an internal wound core (or stacked core). It has advantages such as high energy density, long cycle service life, and strong temperature adaptability. However, the battery cell of the soft-pack battery will show an expansion and bulging phenomenon during the cycling process. Since the packaging film shell is formed by punching with a convex die, the thickness is thinned the most at the rounded corners of the punching pits. Also, because the cross-section of the wound core is in a runway shape and the cross-section of the stacked core is rectangular, when expanding, the four corners of the wound core or stacked core directly squeeze the four rounded corners of the packaging film shell's punching pits. After cyclic expansion, the packaging film shell is squeezed. Especially in application conditions of high rate and fast charging, in severe cases, it may even cause corner cracking, etc. The main solution to the existing corner cracking is to reduce the extrusion force between the inner core and the film shell. The most direct method is to increase the space of the film shell or reduce the volume of the wound core. However, the above methods will reduce the energy density. Summary of the Utility Model

[0003] In view of this, the purpose of the utility model is to provide a battery cell and a soft-pack battery, which are used to solve the problem of reduced energy density caused by measures such as increasing the space of the film shell to improve corner cracking.

[0004] To solve the above technical problems, the utility model provides a battery cell, which includes a packaging film shell and an inner core. At least one side of the packaging film shell has a punching pit; the inner core is arranged inside the punching pit; a protective adhesive paper is arranged on the surface of the inner core close to the punching pit, and the protective adhesive paper covers at least one area corresponding to the rounded corner of the punching pit of the inner core and the punching pit.

[0005] Optionally, in the thickness direction of the inner core, when one side of the packaging film shell has the punching pit, the protective adhesive paper is arranged on the surface of the inner core close to the punching pit on the single side.

[0006] Optionally, in the thickness direction of the inner core, when both sides of the packaging film shell have the punching pits, and the ratio of the depth of the punching pit on the first side to the depth of the punching pit on the second side is greater than 1.1, the protective adhesive paper is arranged on the surface of the inner core close to the punching pit on the first side.

[0007] Optionally, in the thickness direction of the inner core, when both sides of the packaging film shell have punching pits, and the ratio of the depth of the punching pit on the first side to the depth of the punching pit on the second side ranges from 1:1.1 to 1.1:1 and includes the values at both ends, the protective adhesive paper is arranged on the surface of the inner core close to the punching pit on the first side and on the surface of the inner core close to the punching pit on the second side.

[0008] Optionally, the thickness of the protective adhesive tape ranges from 10 μm to 40 μm, excluding the two end values.

[0009] Optionally, the inner core is a stacked core; the stacked core is formed by laminating a positive electrode sheet, a separator, and a negative electrode sheet; a positive electrode tab is provided on the positive electrode sheet in the length direction of the stacked core, a negative electrode tab is provided on the negative electrode sheet in the length direction of the stacked core, and a first tab adhesive and a second tab adhesive are respectively provided on the positive electrode tab and the negative electrode tab.

[0010] Optionally, the inner core is a wound core; the wound core is formed by winding a positive electrode sheet, a separator, and a negative electrode sheet; on the same side in the length direction of the wound core, a positive electrode tab is provided on the positive electrode sheet, a negative electrode tab is provided on the negative electrode sheet, and a first tab adhesive and a second tab adhesive are respectively provided on the positive electrode tab and the negative electrode tab; the wound core includes a first arc portion, a straight portion, and a second arc portion sequentially connected along its width direction; a finishing adhesive tape is provided on the straight portion, and the finishing adhesive tape covers the tail of the wound core.

[0011] Optionally, the protective adhesive tape is a through-type adhesive tape, and the through-type adhesive tape includes a first arc region, a first straight region, and a second arc region sequentially connected along the width direction of the wound core; the first arc region covers at least part of the first arc portion; the first straight region covers the entire straight portion; the second arc region covers at least part of the second arc portion;

[0012] And / or, the protective adhesive tape is a non-through-type adhesive tape, and the non-through-type adhesive tape includes a third arc region and a second straight region sequentially connected along the width direction of the wound core; the third arc region covers at least part of the first arc portion; the second straight region covers part of the straight portion.

[0013] Optionally, in the width direction of the wound core, the ending position of the first arc region is less than 1 / 3 times the thickness of the wound core away from the edge of the wound core;

[0014] And / or, in the width direction of the wound core, the ending position of the second arc region is less than 1 / 3 times the thickness of the wound core away from the edge of the wound core;

[0015] And / or, in the width direction of the wound core, the ending position of the third arc region is less than 1 / 3 times the thickness of the wound core away from the edge of the wound core;

[0016] And / or, in the width direction of the wound core, the length of the straight portion covered by the second straight region is greater than or equal to 1 mm.

[0017] Optionally, in the length direction of the core, the dimension by which the protective adhesive tape near the pole tab side of the core extends beyond the edge of the positive electrode sheet is greater than 0.2 mm and less than 1 mm plus 1 / 2 times the depth of the indentation;

[0018] And / or, in the length direction of the core, the dimension by which the protective adhesive tape near the non-pole tab side of the core extends beyond the edge of the positive electrode sheet is greater than 0.2 mm and less than the depth of the indentation.

[0019] Optionally, in the length direction of the core, the distance between the protective adhesive tape near the pole tab side of the core and the end adhesive tape is greater than 1 mm;

[0020] And / or, in the length direction of the core, the distance between the protective adhesive tape near the non-pole tab side of the core and the end adhesive tape is greater than 1 mm.

[0021] Optionally, when the protective adhesive tape is the non-penetrating adhesive tape, in the width direction of the core, the distance between the protective adhesive tape near the first pole tab adhesive and the first pole tab adhesive is greater than 1 mm;

[0022] And / or, when the protective adhesive tape is the non-penetrating adhesive tape, in the width direction of the core, the distance between the protective adhesive tape near the second pole tab adhesive and the second pole tab adhesive is greater than 1 mm.

[0023] To solve the above technical problems, the present utility model further provides a soft-pack battery, comprising: the above-described battery cell.

[0024] It can be seen that for a battery cell provided by the present utility model, by arranging a protective adhesive tape in the area corresponding to the rounded corners of the indentations of the inner core and the packaging film shell, the overall safety of the battery cell is improved, and it is avoided that the battery cell expands and directly contacts the rounded corners of the indentations of the packaging film shell after multiple cycles, thereby reducing the risk of corner cracking, and thus avoiding the reduction of the energy density due to improvement measures such as increasing the space of the film shell. The present utility model further provides a soft-pack battery having the above beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present utility model, and for those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0026] Figure 1 A front view of the non-pole tab side of a battery cell provided by an embodiment of the present utility model;

[0027] Figure 2 Another front view of the non-tab side of the battery cell provided by the embodiment of the present utility model;

[0028] Figure 3 A top view of a battery cell provided by the embodiment of the present utility model;

[0029] Figure 4 Another top view of a battery cell provided by the embodiment of the present utility model;

[0030] Figure 5 The cross-sectional view of the tab side of the first soft-pack battery provided by the embodiment of the present utility model;

[0031] Figure 6 The cross-sectional view of the tab side of the second soft-pack battery provided by the embodiment of the present utility model;

[0032] Figure 7 The cross-sectional view of the tab side of the third soft-pack battery provided by the embodiment of the present utility model;

[0033] Figure 8 The cross-sectional view of the tab side of the fourth soft-pack battery provided by the embodiment of the present utility model;

[0034] Figure 9 The cross-sectional view of the tab side of the fifth soft-pack battery provided by the embodiment of the present utility model;

[0035] Figure 10 The cross-sectional view of the tab side of the sixth soft-pack battery provided by the embodiment of the present utility model.

[0036] The description of the reference numerals is as follows:

[0037] 1 - winding core; 11 - first arc portion; 12 - straight portion; 13 - second arc portion; 21 - through adhesive tape; 22 - non-through adhesive tape; 3 - positive electrode sheet; 31 - positive tab; 32 - first tab adhesive; 41 - negative tab; 42 - second tab adhesive; 5 - end adhesive tape; 6 - packaging film shell; 61 - punched corner radius;

[0038] L1 - the distance from the end position to the edge of the winding core;

[0039] L2 - the length of the straight portion covered by the second straight zone;

[0040] d1 - the dimension that the protective adhesive tape on the tab side near the winding core exceeds the edge of the positive electrode sheet;

[0041] d2 - the dimension that the protective adhesive tape on the non-tab side near the winding core exceeds the edge of the positive electrode sheet;

[0042] d3 - the distance between the protective adhesive tape on the tab side near the winding core and the end adhesive tape;

[0043] The distance between the protective adhesive tape on the non-tab side close to the core and the end adhesive tape;

[0044] The distance between the protective adhesive tape close to the first tab adhesive and the first tab adhesive;

[0045] The distance between the protective adhesive tape close to the second tab adhesive and the second tab adhesive;

[0046] T1 - The depth of the first side punch;

[0047] T2 - The depth of the second side punch;

[0048] X - The width direction;

[0049] Y - The length direction;

[0050] Z - The thickness direction. Detailed implementation manners

[0051] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present utility model.

[0052] Please refer to Figures 1 to 10 , a battery cell provided by an embodiment of the present utility model includes a packaging film shell 6 and an inner core. At least one side of the packaging film shell 6 has a punch; the inner core is disposed inside the punch; a protective adhesive tape is disposed on the surface of the inner core close to the punch, and the protective adhesive tape covers at least one area corresponding to the punch fillet 61 of the inner core and the punch.

[0053] This embodiment does not limit the specific type of the inner core. For example, the inner core can be a stacked core; the stacked core can be formed by laminating a positive electrode sheet, a separator, and a negative electrode sheet; a positive tab is disposed on the positive electrode sheet in the length direction of the stacked core, a negative tab is disposed on the negative electrode sheet in the length direction of the stacked core, and a first tab adhesive and a second tab adhesive are respectively disposed on the positive tab and the negative tab. It should be noted that when a stacked core is used as the inner core, the area covered by the protective adhesive tape is the edge of the stacked core and the area corresponding to the punch fillet 61 of the packaging film shell.

[0054] The core of this embodiment can also be a wound core 1, which can be formed by winding a positive electrode sheet 3, a separator, and a negative electrode sheet; on the same side in the length direction Y of the wound core 1, a positive electrode tab 31 is provided on the positive electrode sheet 3, and a negative electrode tab 41 is provided on the negative electrode sheet. The positive electrode tab 31 and the negative electrode tab 41 are respectively provided with a first tab adhesive 32 and a second tab adhesive 42; the wound core 1 includes a first arc portion 11, a straight portion 12, and a second arc portion 13 that are sequentially connected along its width direction X; a finishing adhesive tape 5 is provided on the straight portion 12, and the finishing adhesive tape 5 covers the tail of the wound core 1. It should be noted that when the wound core 1 is used as the core, the area covered by the protective adhesive tape is the arc portion of the wound core 1 and the area corresponding to the punched corner 61 of the packaging film shell 6. As Figure 1 and Figure 2 shown in the battery cell, the battery cell is composed of a wound core 1 pasted with a protective adhesive tape. The wound core is made by a winding process. When winding, arc-shaped regions will be formed at the bending portions on both sides. These two arc-shaped regions on both sides are the first arc portion 11 and the second arc portion 13, and the straight region between the two arc-shaped regions on both sides is the straight portion 12. The whole formed by sequentially connecting the first arc portion 11, the straight portion 12, and the second arc portion 13 is in the shape of a runway. Among them, Figure 1 the shown protective adhesive tape is a through-type adhesive tape 21, which covers at least part of the first arc portion 11, the entire straight portion 12, and at least part of the second arc portion 13 of the wound core 1. Figure 2 the shown protective adhesive tape is a non-through-type adhesive tape 22, which covers at least part of the first arc portion 11 and part of the straight portion 12 of the wound core 1.

[0055] This embodiment does not limit the specific type of the protective adhesive tape. For example, the protective adhesive tape can be a through-type adhesive tape 21; the through-type adhesive tape 21 can include a first arc region, a first straight region, and a second arc region that are sequentially connected along the width direction X of the wound core 1; the first arc region covers at least part of the first arc portion 11; the first straight region covers the entire straight portion 12; the second arc region covers at least part of the second arc portion 13. As Figure 1 shown, a through-type adhesive tape 21 is separately pasted on the upper end of the wound core 1. One end of the through-type adhesive tape 21 extends to the first arc portion 11, and the other end extends to the second arc portion 13, which can cover at least part of the first arc portion 11, the entire straight portion 12, and at least part of the second arc portion 13 at the same time. In addition, a through-type adhesive tape 21 can also be separately pasted on the lower end of the wound core 1.

[0056] The protective adhesive tape of this embodiment can also be a non-through-type adhesive tape 22; the non-through-type adhesive tape 22 can include a third arc region and a second straight region that are sequentially connected along the width direction X of the wound core 1; the third arc region covers at least part of the first arc portion 11; the second straight region covers part of the straight portion 12. As Figure 2As shown, a non-through adhesive tape 22 is separately pasted at a vertex position of the core 1. One end of the non-through adhesive tape 22 extends to the first arc portion 11, and the other end extends to the straight portion 12, covering only a part of the first arc portion 11 and a part of the straight portion 12. In addition, a non-through adhesive tape 22 can be separately pasted at the other three vertex positions of the core 1.

[0057] From Figure 2 It can be seen that in this embodiment, the second straight area of the non-through adhesive tape 22 only covers a part of the straight portion 12 of the core 1, so it can be regarded as the through adhesive tape 21 being truncated at the straight portion 12 of the core 1. And the non-through adhesive tape 22 adopts the same adhesive pasting method as the through adhesive tape 21 at the arc portion of the core 1. Therefore, the pasting area of the third arc area of the non-through adhesive tape 22 can be the same as the pasting areas of the first arc area and the second arc area of the through adhesive tape 21. That is, in the width direction X of the core 1, the distance L1 from the end positions of the non-through adhesive tape 22 and the through adhesive tape 21 to the edge of the core 1 can adopt the same value range. For example, in the width direction X of the core 1, the distance L1 from the end position of the first arc area to the edge of the core 1 can be less than 1 / 3 times the thickness of the core 1; and / or, in the width direction X of the core 1, the distance L1 from the end position of the second arc area to the edge of the core 1 can be less than 1 / 3 times the thickness of the core 1; and / or, in the width direction X of the core 1, the distance L1 from the end position of the third arc area to the edge of the core 1 can be less than 1 / 3 times the thickness of the core 1.

[0058] In order to ensure the fitting effect between the non-through adhesive tape 22 and the core 1 during adhesive pasting, in this embodiment, in the width direction X of the core 1, the length L2 of the straight portion 12 covered by the second straight area can be greater than or equal to 1 mm.

[0059] Please refer to Figure 3 and Figure 4 , Figure 3 is a top view of a battery cell provided by an embodiment of the present invention; Figure 4 is a top view of another battery cell provided by an embodiment of the present invention. Figure 3 and Figure 4 In, on the same side in the length direction Y of the core 1, a positive electrode tab 31 is led out from the positive electrode sheet 3 in the core 1, and the positive electrode tab 31 is wrapped with a first tab adhesive 32; a negative electrode tab 41 is led out from the negative electrode sheet, and the negative electrode tab 41 is wrapped with a second tab adhesive 42. This side is the tab side, and the other side opposite thereto is the non-tab side. In addition, the positions of the positive electrode tab and the negative electrode tab can be exchanged, and this embodiment does not limit the positions of the positive electrode tab and the negative electrode tab. Among them, Figure 3 As shown, two through adhesive tapes 21 are pasted on the surface of the core 1, and the two through adhesive tapes 21 are respectively arranged at positions close to the tab side and positions close to the non-tab side.Figure 4 Four non-penetrating adhesive tapes 22 are pasted on the surface of the core 1 shown, and the four non-penetrating adhesive tapes 22 are respectively arranged at four corner positions and are not connected to each other.

[0060] In order to ensure that the protective adhesive tape plays a role in protecting the packaging film shell 6 while not entering the top sealing area and affecting the tightness of the packaging film shell 6, in the length direction Y of the core 1 in this embodiment, the dimension d1 by which the protective adhesive tape near the pole tab side of the core 1 exceeds the edge of the positive electrode sheet 3 can be greater than 0.2 mm and less than 1 mm plus 1 / 2 times the depth of the punching pit; and / or, in the length direction Y of the core 1, the dimension d2 by which the protective adhesive tape near the non-pole tab side of the core 1 exceeds the edge of the positive electrode sheet 3 can be greater than 0.2 mm and less than the depth of the punching pit.

[0061] It should be noted that in the thickness direction Z of the core 1 in this embodiment, the projections of the protective adhesive tape and the end adhesive tape 5 of the core 1 cannot overlap. As Figure 3 and Figure 4 shown, in order to avoid loss of the energy density of the battery cell, in the length direction Y of the core 1 in this embodiment, the distance d3 between the protective adhesive tape near the pole tab side of the core 1 and the end adhesive tape 5 can be greater than 1 mm; and / or, in the length direction Y of the core 1, the distance d4 between the protective adhesive tape near the non-pole tab side of the core 1 and the end adhesive tape 5 can be greater than 1 mm.

[0062] It should be noted that when the protective adhesive tape is a non-penetrating adhesive tape 22 in this embodiment, in the thickness direction Z of the core 1, the projections of the non-penetrating adhesive tape 22 and the first pole tab adhesive 32 and the second pole tab adhesive 42 cannot overlap. As Figure 4 shown, in order to avoid loss of the energy density of the battery cell, in the width direction X of the core 1 in this embodiment, the distance d5 between the protective adhesive tape near the first pole tab adhesive 32 and the first pole tab adhesive 32 can be greater than 1 mm; and / or, when the protective adhesive tape is a non-penetrating adhesive tape 22, in the width direction X of the core 1, the distance d6 between the protective adhesive tape near the second pole tab adhesive 42 and the second pole tab adhesive 42 can be greater than 1 mm.

[0063] Considering that if the protective adhesive tape is too thin, the protection effect is average and the process control is difficult; if the protective adhesive tape is too thick, it may cause the thickness of the battery cell to be too thick, resulting in loss of the energy density of the battery cell. The thickness range of the protective adhesive tape in this embodiment can be 10 μm to 40 μm, excluding the values at both ends.

[0064] This embodiment does not limit the specific material of the packaging film shell 6, and the packaging film shell 6 can be but is not limited to an aluminum-plastic film.

[0065] This embodiment does not limit the specific type of the packaging film shell 6. For example, it can include the following types:

[0066] As Figure 5 and Figure 6 shown, on one side of the packaging film shell 6 in the thickness direction Z of the inner core, there are indentations;

[0067] As Figure 7 and Figure 8 shown, on both sides of the packaging film shell 6 in the thickness direction Z of the inner core, there are indentations, and the ratio of the depth T1 of the indentation on the first side to the depth T2 of the indentation on the second side is greater than 1.1;

[0068] As Figure 9 and Figure 10 shown, on both sides of the packaging film shell 6 in the thickness direction Z of the inner core, there are indentations, and the ratio range of the depth T1 of the indentation on the first side to the depth T2 of the indentation on the second side is 1:1.1 to 1.1:1, and includes the values at both ends.

[0069] It should be noted that the packaging film shell 6 used in this embodiment is formed by punching with a convex die, and after punching, indentations for accommodating the inner core as shown in Figures 5 to 10 will be formed on the packaging film shell 6, and the corner positions of the indentations are rounded, and this rounded corner is the indentation rounded corner 61.

[0070] For different types of packaging film shells 6 in this embodiment, different ways of pasting protective adhesive tapes can be adopted. For example:

[0071] When there are indentations on one side of the packaging film shell 6 in the thickness direction Z of the inner core, a protective adhesive tape can be provided on the surface of the inner core close to the indentation on one side. As Figure 5 and Figure 6 shown, the inner core adopts a roll core 1, and this roll core 1 is arranged inside the indentation. Among them, Figure 5 a non-penetrating adhesive tape 22 is adopted, and this non-penetrating adhesive tape 22 is only pasted on one side of the roll core 1 close to the indentation; Figure 6 a penetrating adhesive tape 21 is adopted, and this penetrating adhesive tape 21 is also only pasted on one side of the roll core 1 close to the indentation.

[0072] When there are indentations on both sides of the packaging film shell 6 in the thickness direction Z of the inner core, and the ratio of the depth T1 of the indentation on the first side to the depth T2 of the indentation on the second side is greater than 1.1, a protective adhesive tape can be provided on the surface of the inner core close to the indentation on the first side. As Figure 7 and Figure 8 shown, the inner core adopts a roll core 1, and this roll core 1 is arranged inside the indentation on the first side and the indentation on the second side. Among them, Figure 7 a non-penetrating adhesive tape 22 is adopted, and the indentation on the first side of the packaging film shell 6 is deeper, and this non-penetrating adhesive tape 22 is only pasted on one side of the roll core 1 close to the deep indentation; Figure 8 a penetrating adhesive tape 21 is adopted, and the indentation on the first side of the packaging film shell 6 is deeper, and this penetrating adhesive tape 21 is also only pasted on one side of the roll core 1 close to the deep indentation.

[0073] In the thickness direction Z of the inner core, both sides of the packaging film shell 6 have indentations. When the ratio range of the depth T1 of the first-side indentation to the depth T2 of the second-side indentation is 1:1.1 to 1.1:1 and includes the values at both ends, protective adhesive tapes can be provided on the surface of the inner core close to the first-side indentation and the surface of the inner core close to the second-side indentation. As Figure 9 and Figure 10 shown, the inner core uses a reel core 1, and this reel core 1 is arranged inside the first-side indentation and the second-side indentation. Among them, Figure 9 Using a non-penetrating adhesive tape 22, the first-side indentation of the packaging film shell 6 is a deep indentation, the second-side indentation of the packaging film shell 6 is a shallow indentation, and non-penetrating adhesive tapes 22 are pasted on both the side of the reel core 1 close to the deep indentation and the side close to the shallow indentation; Figure 10 Using a penetrating adhesive tape 21, the first-side indentation of the packaging film shell 6 is a deep indentation, the second-side indentation of the packaging film shell 6 is a shallow indentation, and penetrating adhesive tapes 21 are pasted on both the side of the reel core 1 close to the deep indentation and the side close to the shallow indentation.

[0074] Based on the above embodiments, the present utility model improves the overall safety of the battery cell by providing protective adhesive tapes in the areas corresponding to the rounded corners of the indentations of the inner core and the packaging film shell, avoiding direct contact between the expanded battery cell and the rounded corners of the indentations of the packaging film shell after multiple cycles of the battery cell, thereby reducing the risk of corner cracking and avoiding the reduction of energy density caused by improvement measures such as increasing the space of the film shell.

[0075] A soft-pack battery provided by an embodiment of the present utility model may include: the above-mentioned battery cell.

[0076] This embodiment does not limit the specific structure and specific parameters of the battery cell. The battery cell provided in the above embodiments can be referred to, and details are not described herein again.

[0077] Based on the above embodiments, the present utility model uses the battery cell provided in the above embodiments, and also solves the problem of energy density reduction caused by improvement measures such as increasing the space of the film shell to improve corner cracking.

[0078] The above has introduced in detail a battery cell and a soft-pack battery provided by the present utility model. For those of ordinary skill in the art, according to the idea of the embodiments of the present utility model, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present utility model.

Claims

1. A battery cell, comprising a packaging film shell and an inner core, characterized in that: At least one side of the packaging film shell has a pit; the inner core is arranged inside the pit; a protective adhesive tape is arranged on the surface of the inner core close to the pit, and the protective adhesive tape covers at least one area corresponding to the rounded corner of the pit between the inner core and the pit.

2. The battery cell according to claim 1, characterized in that: When the packaging film shell has the punching hole on one side in the thickness direction of the inner core, the protective adhesive tape is provided on the surface of the inner core close to the punching hole on the one side.

3. The battery cell according to claim 1, characterized in that: In the thickness direction of the inner core, the packaging film shell has the pits on both sides, and when the ratio of the depth of the first side pit to the depth of the second side pit is greater than 1.1, the protective tape is provided on the surface of the inner core close to the first side pit.

4. The battery cell according to claim 1, characterized in that: In the thickness direction of the inner core, the packaging film shell has the pits on both sides, and the ratio of the depth of the first side pit to the depth of the second side pit is in the range of 1:1.1~1.1:1, and when the values ​​at both ends are included, the surface of the inner core close to the first side pit and the surface of the inner core close to the second side pit are both provided with the protective tape.

5. The battery cell according to claim 1, characterized in that: The thickness of the protective tape ranges from 10 μm to 40 μm, excluding the values ​​at both ends.

6. The battery cell according to any one of claims 1 to 5, characterized in that: The inner core is a stacked core; the stacked core is formed by stacking a positive electrode sheet, a separator and a negative electrode sheet; the positive electrode sheet is provided with a positive electrode ear in the length direction of the stacked core, the negative electrode sheet is provided with a negative electrode ear in the length direction of the stacked core, and the positive electrode ear and the negative electrode ear are respectively provided with a first electrode ear glue and a second electrode ear glue.

7. The battery cell according to any one of claims 1 to 5, characterized in that: The inner core is a winding core; the winding core is formed by winding a positive electrode sheet, a separator and a negative electrode sheet; on the same side in the length direction of the winding core, a positive electrode ear is provided on the positive electrode sheet, and a negative electrode ear is provided on the negative electrode sheet, and the positive electrode ear and the negative electrode ear are respectively provided with a first electrode ear glue and a second electrode ear glue; the winding core includes a first arc portion, a straight portion and a second arc portion connected in sequence along its width direction; the straight portion is provided with a finishing tape, and the finishing tape covers the tail of the winding core.

8. The battery cell according to claim 7, characterized in that: The protective tape is a through-type tape, and the through-type tape comprises a first arc area, a first straight area, and a second arc area sequentially connected along the width direction of the winding core; the first arc area covers at least a portion of the first arc portion; the first straight area covers the entire straight portion; the second arc area covers at least a portion of the second arc portion; And / or, the protective tape is a non-penetrating tape, and the non-penetrating tape includes a third arc area and a second straight area connected in sequence along the width direction of the winding core; the third arc area covers at least part of the first arc portion; and the second straight area covers part of the straight portion.

9. The battery cell according to claim 8, characterized in that: In the width direction of the winding core, the distance between the end position of the first arc area and the edge of the winding core is less than 1 / 3 times the thickness of the winding core; and / or, in the width direction of the winding core, the distance between the end position of the second arc area and the edge of the winding core is less than 1 / 3 times the thickness of the winding core; and / or, in the width direction of the winding core, the distance between the end position of the third arc area and the edge of the winding core is less than 1 / 3 times the thickness of the winding core; And / or, in the width direction of the winding core, the length of the straight portion covered by the second straight area is greater than or equal to 1 mm.

10. The battery cell according to claim 8, characterized in that: In the length direction of the winding core, the protective tape on the side with the pole ear close to the winding core exceeds the edge of the positive electrode sheet by more than 0.2 mm and is less than 1 mm plus 1 / 2 times the depth of the punching pit; And / or, in the length direction of the winding core, the protective tape on the non-ear side of the winding core protrudes beyond the edge of the positive electrode sheet by more than 0.2 mm and is less than the depth of the punching pit.

11. The battery cell according to claim 8, characterized in that: In the length direction of the winding core, the distance between the protective tape close to the lug side of the winding core and the finishing tape is greater than 1 mm; And / or, in the length direction of the winding core, the distance between the protective tape close to the non-ear side of the winding core and the finishing tape is greater than 1 mm.

12. The battery cell according to claim 8, characterized in that: When the protective tape is the non-penetrating tape, in the width direction of the winding core, the distance between the protective tape close to the first tab glue and the first tab glue is greater than 1 mm; And / or, when the protective tape is the non-penetrating tape, in the width direction of the winding core, the distance between the protective tape close to the second tab glue and the second tab glue is greater than 1 mm.

13. A soft pack battery, characterized in that: include: A battery cell as claimed in any one of claims 1 to 12.

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