CN218919076U - Single-folded-edge battery cell insulation wrapping structure and battery module - Google Patents

Abstract

The utility model relates to the technical field of battery cell insulation wrapping, and discloses a single-folded-edge battery cell insulation wrapping structure and a battery module, wherein the single-folded-edge battery cell insulation wrapping structure comprises a battery cell main body and two first insulation sheets; the battery cell main body comprises a battery cell and a membrane for wrapping the battery cell, wherein a conductive layer for isolating outside moisture is arranged in the membrane, the membrane comprises a wrapping part for wrapping the battery cell and a hot-pressing part beyond the battery cell, and the hot-pressing part comprises a hot-pressing base part and two bending parts, wherein the hot-pressing base part and the two bending parts are integrated and extend outwards respectively relative to the wrapping part; the two first insulating sheets are respectively wrapped on the corresponding bending parts, the first insulating sheets are used for covering at least part of the outer edges of the bending parts, and the first insulating sheets are not bonded with the top surface or the bottom surface of the wrapping part. The application mainly solves the technical problem that the battery capacity cannot be further improved due to the fact that the battery thickness is occupied after insulation treatment of two folded edges of the existing battery after hot pressing.

Description

Single-folded-edge battery cell insulation wrapping structure and battery module

Technical Field

The utility model relates to the technical field of battery cell insulation wrapping, in particular to a single-folded-edge battery cell insulation wrapping structure and a battery module.

Background

Along with the increasing requirements of the market on portability and cruising ability of digital products such as mobile phones, the thickness of the digital products is thinner and thinner, and batteries with higher capacity are carried, so that the batteries are designed in a direction of thinner and larger capacity to meet the requirements of the digital products.

In most of the current digital products such as mobile phones, a built-in polymer lithium ion battery is adopted, referring to fig. 1, the polymer lithium ion battery generally wraps a battery cell with an insulating membrane 11, and the positive electrode tab 12 and the negative electrode tab 13 extend outwards relative to the membrane 11. Specifically, referring to fig. 2, the diaphragm 11 is an aluminum plastic film, the outermost layer of the diaphragm 11 is made of insulating nylon 91, the middle layer is made of conductive aluminum layer 92, the innermost layer is made of insulating PP layer 93, and the nylon 91 has an insulating function to prevent the conductive aluminum layer 92 from contacting with the peripheral conductor, so that the diaphragm needs to be placed on the outermost layer; the inner insulating PP layer 93 is provided with a heat-sealing function, so that it is placed in the innermost layer; the middle conductive aluminum layer 92 isolates moisture in the air, and prevents the moisture from entering the cell and reacting to generate gas. In the production process of the battery, the battery cell is first wrapped by the membrane 11, then the region a in fig. 1 (i.e. the region beyond the periphery of the battery cell) is hot-pressed, fig. 2 is a schematic structural diagram of stacking the top membrane 11 and the bottom membrane 11 together before hot-pressing, fig. 3 is a schematic structural diagram of hot-melting the layers of the top membrane 11 and the bottom membrane 11 together after hot-pressing, and as can be seen from fig. 3, the insulating PP layer 93 of the top membrane 11 and the insulating PP layer 93 of the bottom membrane 11 are hot-pressed into a whole. Referring to fig. 4, after the hot pressing is completed, in order to save the space occupied by the battery, two sides of the hot pressed portion of the membrane 11 need to be folded to form two bending portions 1122. Further, since the conductive aluminum layer 92 at the outer edge of the bending portion 1122 is exposed, when the conductive aluminum layer 92 and the battery compartment form a passage, a special chemical reaction causes the conductive aluminum layer 92 to form LiAl alloy and lose sealing effect, and causes safety problems such as bulge and leakage of the battery, so that both bending portions 1122 of the battery need to be insulated.

Referring to fig. 4 and 5 together, two bending portions 1122 of a conventional battery are bent twice, so that the outer edges of the bending portions 1122 are buried inside, and in order to prevent the bending portions 1122 from spontaneously expanding outwards, referring to fig. 6, an insulating mylar sheet 14 is adhered to the top surface of the sheet 11 and the outer surface of the bending portions 1122 in the prior art, so that the bending portions 1122 can be wrapped inside by the mylar sheet 14, and since a portion of the mylar sheet 14 is adhered to the top surface of the sheet 11, the mylar sheet 14 occupies the thickness of the battery, thereby affecting the capacity of the battery and preventing the capacity of the battery from being further increased.

Disclosure of Invention

The utility model aims to provide a single-folded-edge battery core insulation wrapping structure and a battery module, which mainly solve the technical problem that the battery capacity cannot be further improved due to the fact that two folded edges after the existing battery is subjected to hot pressing occupy the thickness of the battery after insulation treatment.

To achieve the purpose, the utility model adopts the following technical scheme:

a single-folded-edge cell insulation wrap structure, comprising:

the battery cell comprises a battery cell body and a membrane wrapping the battery cell, wherein a conductive layer used for isolating outside moisture is arranged in the membrane, the membrane comprises a wrapping part used for wrapping the battery cell and a hot-pressing part exceeding the battery cell, and the hot-pressing part comprises an integral hot-pressing base part and two bending parts, wherein the hot-pressing base part extends outwards relative to the wrapping part, and the two bending parts are oppositely arranged at two sides of the battery cell;

the two first insulating sheets are respectively wrapped on the corresponding bending parts, the first insulating sheets are used for covering the outer edges of at least part of the bending parts, and the first insulating sheets are not bonded with the top surface or the bottom surface of the wrapping part.

In one embodiment, the membrane is provided with a bending line for bending the bending part, the bending part comprises a first outer edge, a second outer edge and a third outer edge which are sequentially connected, the second outer edge is arranged opposite to the bending line, and the first outer edge and the third outer edge are both connected with the bending line;

the first insulating sheet wraps at least a portion of the second outer edge.

In one embodiment, the hot pressing base is provided with a fourth outer edge respectively connected with the first outer edges of the two bending parts, and the single-folded-edge electric core insulation wrapping structure further comprises a second insulation sheet, wherein the second insulation sheet wraps the fourth outer edge.

In one embodiment, the second insulating sheet comprises a first wrapping member and two second wrapping members bent with respect to the first wrapping member;

the first wrapping piece wraps the fourth outer edge, and the second wrapping piece wraps one part of the first outer edge and the second outer edge of the corresponding bending part.

In one embodiment, the first insulating sheet wraps around the entire second outer rim and around the second wrapper.

In one embodiment, the hot pressing base is provided with a positive electrode lug and a negative electrode lug which are respectively and electrically connected with the battery cell in an outward protruding way, and the first wrapping piece is provided with a notch for avoiding the positive electrode lug and the negative electrode lug.

In one embodiment, the first insulating sheet is extended and bent with a folded edge portion for wrapping the third outer edge, and the folded edge portion is bonded with an end face of the wrapping portion, which faces away from the hot pressing base.

In one embodiment, the first insulating sheet and the second insulating sheet are mylar sheets, and the first insulating sheet is bonded to the corresponding bending portion.

In one embodiment, a glue layer is adhered between the first insulating sheet and the side surface of the wrapping portion.

The utility model also provides a battery module, which comprises a protection board assembly and the single-folded-edge battery cell insulating wrapping structure in any one of the technical schemes, wherein the protection board assembly is arranged at the adjacent position of the hot pressing base and is electrically connected with the battery cell.

Compared with the prior art, the single-folded-edge battery cell insulation wrapping structure provided by the utility model has at least the following beneficial effects:

this technical scheme will be originally the kink that secondary was bent changes into single bending to wrap up but can not bond in the top surface or the bottom surface of parcel portion to the outside edge of kink with first insulating piece, promptly, first insulating piece is under the prerequisite of wrapping up in order to realize insulatingly the inside conducting layer of kink, and the thickness of battery can not be occupied to first insulating piece of this scheme, and the thickness that reduces can release for the electric core, under the unable prerequisite of increasing of electric core final thickness, adopts this parcel structure can improve the capacity of battery.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the utility model, and that other drawings can be obtained from these drawings without inventive faculty for a person skilled in the art.

FIG. 1 is a front view of a prior art battery before being folded;

FIG. 2 is a schematic view of the structure of a membrane of the outer layer of a conventional battery before hot pressing;

FIG. 3 is a schematic view of a membrane of an outer layer of a conventional battery after hot pressing;

FIG. 4 is a schematic view of the structure of two sides of a conventional battery after hemming;

FIG. 5 is a partial enlarged view at B in FIG. 4;

FIG. 6 is a schematic view of a prior art battery with two side flaps wrapped around Mylar film sheets, respectively;

fig. 7 is a schematic structural diagram of a single-folded-edge electrical core insulation package structure according to an embodiment of the present application;

fig. 8 is a structural exploded view of a single-folded-edge electrical core insulation package structure according to an embodiment of the present disclosure;

fig. 9 is a schematic structural diagram of a battery cell main body according to an embodiment of the present disclosure;

FIG. 10 is an enlarged view of a portion of FIG. 7 at C;

FIG. 11 is a partial enlarged view at D in FIG. 7;

fig. 12 is a schematic structural diagram of a battery module according to an embodiment of the present disclosure.

Wherein, each reference sign in the figure:

1. a cell body; 11. a membrane; 111. a wrapping portion; 112. a hot pressing part;

1121. hot pressing the base; 11211. a fourth outer edge; 1122. a bending part; 11221. a first outer edge; 11222. a second outer edge; 11223. a third outer edge;

12. a positive electrode tab; 13. a negative electrode ear; 14. a Mylar film; 15. a bending line;

2. a first insulating sheet; 21. a hemming section;

3. a second insulating sheet; 31. a first wrapper; 311. a notch; 32. a second wrapper;

4. a glue layer; 5. a protective plate assembly;

91. nylon; 92. a conductive aluminum layer; 93. insulating PP layer.

Detailed Description

In order to make the technical problems, technical schemes and beneficial effects to be solved by the present application more clear, the present application is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.

It will be understood that when an element is referred to as being "mounted" or "disposed" on another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

It is to be understood that the terms "upper," "lower," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship based on that shown in the drawings, merely to facilitate the description of the present application and to simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present application.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, the meaning of "a plurality" is two or more, unless explicitly defined otherwise.

The present utility model will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present utility model more apparent.

Referring to fig. 7 and 8, the present embodiment provides a single-folded-edge battery cell insulation package structure, which includes a battery cell main body 1, two first insulation sheets 2 and a second insulation sheet 3.

Referring to fig. 9, the battery cell main body 1 includes a battery cell (not shown) and a membrane 11 for wrapping the battery cell, wherein a conductive layer (not shown) for isolating outside moisture is disposed in the membrane 11, and the membrane 11 is preferably an existing aluminum plastic film, i.e., the conductive layer is a conductive aluminum layer mentioned in the background art.

Referring to fig. 9 again, specifically, the membrane 11 includes a wrapping portion 111 for wrapping the battery cell and a hot-pressing portion 112 beyond the battery cell, the hot-pressing portion 112 corresponds to the region a in the frame of fig. 1, the hot-pressing portion 112 further includes a hot-pressing base 1121 and two bending portions 1122 that are integral and extend outwards relative to the wrapping portion 111, and the two bending portions 1122 are oppositely disposed at two sides of the battery cell. Further, the positive electrode tab 12 and the negative electrode tab 13 are protruded from the hot pressing base 1121, and the positive electrode tab 12 and the negative electrode tab 13 are electrically connected to the internal battery cell, respectively.

Referring to fig. 8, the film 11 has a bending line 15 for bending the bending portion 1122, and the bending portion 1122 has a first outer edge 11221, a second outer edge 11222 and a third outer edge 11223 connected in sequence, wherein the second outer edge 11222 and the bending line 15 are disposed opposite to each other, and the first outer edge 11221 and the third outer edge 11223 are directly connected to the bending line 15. Since the first outer edge 11221, the second outer edge 11222, and the third outer edge 11223 have exposed conductive layers, an insulating process, particularly a second outer edge 11222 having a long length, is required.

Referring to fig. 8 again, the hot pressing base 1121 has a fourth outer edge 11211, one end of the fourth outer edge 11211 is connected to the first outer edge 11221 of one of the bending portions 1122, the other end of the fourth outer edge 11211 is connected to the first outer edge 11221 of the other bending portion 1122, and the fourth outer edge 11211 also has an exposed conductive layer, so that it is also preferable to perform insulation treatment.

Referring to fig. 7, in the present embodiment, one of the first insulating sheets 2 is used to wrap the second outer edge 11222 of one of the bent portions 1122, and the other one of the first insulating sheets 2 is used to wrap the second outer edge 11222 of the other one of the bent portions 1122, so as to avoid forming a via between the second outer edge 11222 of the bent portion 1122 and the inside of the cell. Specifically, the first insulating sheet 2 is bonded to the corresponding bent portion 1122.

Referring to fig. 7, 8 and 10, the second insulating sheet 3 includes a first wrapping member 31 and two second wrapping members 32 bent with respect to the first wrapping member 31, the first wrapping member 31 wraps the fourth outer edge 11211 of the hot-pressed base 1121, one of the second wrapping members 32 wraps the first outer edge 11221 and a small portion of the second outer edge 11222 of one of the bending portions 1122, and the other second wrapping member 32 wraps the first outer edge 11221 and a small portion of the second outer edge 11222 of the other bending portion 1122, so that it can be seen that the second insulating sheet 3 is used to avoid the fourth outer edge 11211 and the two first outer edges 11221 from forming a passage with the inside of the battery cell. In addition, the first wrapping member 31 is provided with a notch 311, and the notch 311 is used for avoiding the positive tab 12 and the negative tab 13 from extending outwards.

Referring to fig. 7 and 10 again, it is preferable that the first insulating sheet 2 wraps the entire second outer edge 11222 and the first insulating sheet 2 wraps the second wrapping member 32, so as to ensure that the second outer edge 11222 is not exposed outward, so as to improve the insulation reliability of the bending portion 1122.

Referring to fig. 8, the first insulating sheet 2 is extended and bent with a folded portion 21, and the folded portion 21 is adhered to an end surface of the wrapping portion 111 facing away from the hot pressing base 1121 and is used for wrapping the third outer edge 11223, so as to avoid forming a path between the third outer edge 11223 and the inside of the cell.

Referring to fig. 7 and 11, a glue layer 4 is adhered between the first insulating sheet 2 and the side surface of the wrapping portion 111, and the glue layer 4 can fix the bending portion 1122 on the side surface, so as to reduce the probability of fatigue damage of the bending portion 1122 caused by repeated bending carelessly. The adhesive layer 4 may be double-sided adhesive or spot-gluing, and the protection scope of the present embodiment is provided that the first insulating sheet 2 and the side surface of the wrapping portion 111 are adhered together by glue.

Through the above structural design, the first insulating sheet 2 and the second insulating sheet 3 jointly wrap and cover all outer edges of the hot pressing part 112, so that the conductive layer in the hot pressing part 112 is ensured not to be exposed to easily form a passage with the battery cell. The first insulating sheet 2 and the second insulating sheet 3 of the present embodiment are each preferably a conventional mylar sheet.

To sum up, this technical scheme will be originally the kink 1122 that the secondary was bent changes into single bending, and first insulating piece 2 and second insulating piece 3 are all not bonded on the top surface or the bottom surface of parcel 111, namely, first insulating piece 2 and second insulating piece 3 are under the prerequisite of wrapping up in order to realize insulating to the inside conducting layer of kink 1122, and the thickness of battery can not be taken up to first insulating piece 2 and second insulating piece 3 of this scheme, and the thickness that reduces can release to the electric core, and under the prerequisite that the final thickness of electric core was restricted, the volume of battery can be improved to the insulating parcel structure of this embodiment of adoption.

Referring to fig. 12, the present embodiment further provides a battery module, which includes the protection plate assembly 5 and the single-folded-edge battery cell insulation package structure. Specifically, the protective plate assembly 5 is disposed adjacent to the hot-pressed base 1121, and the positive tab 12 and the negative tab 13 are electrically connected to the protective plate assembly 5, so that the protective plate assembly 5 and the battery cell are electrically connected. The protection board assembly 5 is in the prior art, and the protection board assembly 5 is used for protecting the battery cell when the battery cell is overcharged, overdischarged, overcurrent and short-circuited.

The foregoing description of the preferred embodiments of the present utility model has been provided for the purpose of illustrating the general principles of the present utility model and is not to be construed as limiting the scope of the utility model in any way. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model, and other embodiments of the present utility model as will occur to those skilled in the art without the exercise of inventive faculty, are intended to be included within the scope of the present utility model.

Claims (10)

1. The utility model provides a single hem electric core insulation package structure which characterized in that includes:

the battery cell comprises a battery cell body and a membrane wrapping the battery cell, wherein a conductive layer used for isolating outside moisture is arranged in the membrane, the membrane comprises a wrapping part used for wrapping the battery cell and a hot-pressing part exceeding the battery cell, and the hot-pressing part comprises an integral hot-pressing base part and two bending parts, wherein the hot-pressing base part extends outwards relative to the wrapping part, and the two bending parts are oppositely arranged at two sides of the battery cell;

the two first insulating sheets are respectively wrapped on the corresponding bending parts, the first insulating sheets are used for covering the outer edges of at least part of the bending parts, and the first insulating sheets are not bonded with the top surface or the bottom surface of the wrapping part.

2. The single-flanging electric core insulation package structure according to claim 1, wherein the membrane is provided with a bending line for bending the bending part, the bending part comprises a first outer edge, a second outer edge and a third outer edge which are sequentially connected, the second outer edge is arranged opposite to the bending line, and the first outer edge and the third outer edge are both connected with the bending line;

the first insulating sheet wraps at least a portion of the second outer edge.

3. The single-folded cell insulation package structure of claim 2, wherein the hot-press base has fourth outer edges respectively engaged with the first outer edges of the two bent portions, and the single-folded cell insulation package structure further comprises a second insulation sheet wrapping the fourth outer edges.

4. The single-folded-edge cell insulation wrap structure of claim 3, wherein the second insulation sheet comprises a first wrap and two second wraps folded relative to the first wrap;

the first wrapping piece wraps the fourth outer edge, and the second wrapping piece wraps one part of the first outer edge and the second outer edge of the corresponding bending part.

5. The single-folded cell insulation wrap structure of claim 4, wherein said first insulating sheet wraps around the entire second outer edge and around said second wrapper.

6. The single-flanging electric core insulation package structure according to claim 4, wherein the hot-pressing base is provided with a positive electrode lug and a negative electrode lug which are respectively and electrically connected with the electric core in an outward protruding way, and the first package member is provided with a notch for avoiding the positive electrode lug and the negative electrode lug.

7. The single-folded-edge battery cell insulating and wrapping structure according to claim 2, wherein a folded edge portion for wrapping the third outer edge is extended and bent on the first insulating sheet, and the folded edge portion is bonded to an end face of the wrapping portion, which faces away from the hot-pressing base.

8. The single-folded-edge battery cell insulation package structure of claim 3, wherein the first insulation sheet and the second insulation sheet are mylar sheets, and the first insulation sheet is bonded to the corresponding bending portion.

9. The single-folded-edge cell insulation package structure of claim 1, wherein an adhesive layer is adhered between the first insulation sheet and the side surface of the package portion.

10. A battery module comprising a protective plate assembly and the single-folded-edge battery cell insulating package structure according to any one of claims 1 to 9, wherein the protective plate assembly is disposed at a position adjacent to the hot-press base and is electrically connected with the battery cell.

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