Lithium battery cell insulation Mylar film

Abstract

The utility model discloses a lithium battery cell insulation Mylar film which comprises a film body, side edge films are integrally formed on the two sides of the film body, a bottom film is integrally formed between every two adjacent film bodies, through holes are formed in the film body, the side edge films and the bottom film, grooves are formed among the through holes in the film body, the side edge films and the bottom film, and the side edge films are arranged in the grooves. And the grooves are communicated with the through holes in the membrane body, the side membranes and the bottom membrane and are communicated with each side of the membrane body, each side membrane and each side of the bottom membrane. The battery aluminum shell has the advantages that the through holes are formed in the mold body, the side films and the bottom film, the grooves are integrally formed among the through holes, and the grooves are matched with the through holes under the capillary action, so that electrolyte at the bottom of the battery aluminum shell can be effectively drained to the top of a battery cell, and the electrolyte at the top and the bottom of the battery cell can be absorbed more uniformly; the infiltration effect of the battery cell is improved, and the battery cell infiltration time is shortened due to the through holes distributed in the membrane body, the side membrane and the bottom membrane in an array manner, so that the infiltration efficiency of the battery cell is effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of power battery cell packaging, and particularly relates to an insulating Mylar film for lithium battery cells. Background Technique

[0002] With the continuous development of power lithium-ion batteries, which are widely used in the automotive field, new energy vehicle manufacturers have put forward higher requirements for aspects such as the cycle performance and safety of lithium batteries. Before the lithium-ion battery cells are put into the shell, a cell encapsulation film will be wrapped on the surface of the cells to separate the aluminum shell from the cells and play an insulating and protective role. The internal cells of the lithium-ion battery are composed of a positive electrode plate, a separator, and a negative electrode plate, and are infiltrated with electrolyte in the middle. During charging, lithium ions are removed from the positive electrode plate, pass through the electrolyte through the separator, and are embedded in the negative electrode plate; during discharging, lithium ions are removed from the negative electrode plate, pass through the electrolyte through the separator, and are re-embedded in the positive electrode.

[0003] The existing utility model patent with the publication number CN218975511U, a cell encapsulation film, a battery and an electrical device using the same, the cell encapsulation film includes: a film body having opposite first and second surfaces and a protrusion located on the first surface, wherein, a through hole is provided on the protrusion, and the through hole communicates the first surface and the second surface of the film body.

[0004] Using the above patent, the main function of the protrusion is to reduce the gap between the electrode plates and solve the problem of abnormal cell interface caused by too large a gap between the electrode plates. The through hole on the protrusion increases the gas permeability of the electrode plates during the battery formation process, avoids the accumulation of bubbles in the electrode plates under the stress state, and increases the service life of the battery. Although the electrolyte can flow to the cell through the through hole on the protrusion, most of the electrolyte settles at the bottom of the cell. During the charge and discharge process of the battery, the flow path of the electrolyte is too long. After the cell is charged and discharged multiple times, the cell will expand to a certain extent, which will compress the protrusion part, cause the through hole to be blocked, lead to uneven absorption of the electrolyte at the top and bottom of the cell, poor wetting effect of the electrolyte on the cell, low wetting efficiency, and the protrusion increases the thickness of the insulating Mylar film, which is not convenient for the operation of putting the cell into the shell. Content of the Utility Model

[0005] The purpose of the utility model is to provide an insulating Mylar film for lithium battery cells to solve the problems of uneven absorption of the electrolyte at the top and bottom of the cell, poor wetting effect of the electrolyte on the cell, low wetting efficiency, and inconvenience for putting the cell into the shell in the prior art.

[0006] To achieve the above object, the technical solution of the present utility model is: a lithium battery cell insulating Mylar film, including a film body, side films integrally formed on both sides of the film body, and a bottom film integrally formed between two adjacent film bodies. Through holes are provided on the film body, side films and bottom film in a penetrating manner. Grooves are provided between the through holes on the film body, side films and bottom film. The grooves communicate with the through holes on the film body, side films and bottom film, and communicate with the respective sides of the film body, side films and bottom film. Adhesive layers are provided at the edges of the back surfaces of the film body and side films, and at least two adhesive layers are provided in the middle of the back surface of the film body. Crease lines are integrally formed between the film body and the side films, and crease lines are integrally formed between the film body and the bottom film. The through holes are distributed in an equidistant array on the film body, side films and bottom film, the grooves are arranged parallel to each other, and the grooves are integrally formed by stamping.

[0007] The advantages of the present utility model are as follows:

[0008] 1. By providing through holes penetrating through the film body, side films and bottom film, and integrally forming grooves between the respective through holes, the capillary action of the grooves cooperates with the through holes, which can effectively drain the electrolyte at the bottom of the battery aluminum shell to the top of the battery cell, making the electrolyte absorption at the top and bottom of the battery cell more uniform and improving the wetting effect of the battery cell;

[0009] 2. The through holes distributed in an equidistant array on the film body, side films and bottom film reduce the wetting time of the battery cell, thereby effectively improving the wetting efficiency of the battery cell;

[0010] 3. The through holes are on the same plane as the film body, side films and bottom film, reducing the thickness of the Mylar film and facilitating the operation of inserting the battery cell into the shell;

[0011] 4. Adhesive layers are provided at the edges of the back surface of the Mylar film. Through the adhesive layers, the Mylar film can be quickly fixed on the outer surface of the battery cell, playing a role in protecting and insulating the battery cell. Description of the Drawings

[0012] Figure 1 It is a front structural schematic diagram of the present utility model.

[0013] Figure 2 It is a back structural schematic diagram of the present utility model.

[0014] Figure 3 It is a sectional structural schematic diagram of the present utility model along A-A.

[0015] Figure 4 It is the present utility model Figure 3 A partial enlarged structural schematic diagram of part A in the present utility model.

[0016] Figure 5 It is a side structural schematic diagram of the present utility model.

[0017] Figure 6 For the present utility model Figure 4 is a partial enlarged structural schematic diagram of part B in it.

[0018] The meanings of the reference numerals are as follows: film body (1), side film (2), bottom film (3), through hole (4), groove (5), adhesive layer (6), easy crease (7). Specific embodiments

[0019] The present utility model will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0020] As Figures 1 to 6 shown, a lithium battery cell insulating Mylar film includes a film body 1. Side films 2 are integrally formed on both sides of the film body 1. A bottom film 3 is integrally formed between two adjacent film bodies 1. Through holes 4 are formed through the film body 1, side films 2 and bottom film 3. Grooves 5 are formed between the through holes on the film body 1, side films 2 and bottom film 3. The grooves 5 communicate with the through holes 4 on the film body 1, side films 2 and bottom film 3 and communicate with the respective sides of the film body 1, side films 2 and bottom film 3. In order to facilitate the quick fixation of the insulating Mylar film to the battery cell, adhesive layers 6 are provided at the edges of the back surfaces of the film body 1 and side films 2. At least two adhesive layers 6 are provided in the middle of the back surface of the film body 1. In order to facilitate the folding of the side film 2 and bottom film 3 to make the Mylar film closely fit the corners of the battery cell, easy creases 7 are integrally formed between the film body 1 and side film 2, and easy creases 7 are integrally formed between the film body 1 and bottom film 3. In order to further improve the infiltration effect of the electrolyte, the through holes 4 are arranged in an equidistant array on the film body 1, side films 2 and bottom film 3, and the grooves 5 are arranged parallel to each other. In order to reduce the thickness of the Mylar film, the grooves 5 are integrally formed by stamping.

[0021] The working process of the present utility model is as follows: Align the insulating Mylar film with the battery cell, and tear off the protective film on the back adhesive layer 6 of it. Fold the insulating Mylar film through the easy crease 7, paste the insulating Mylar film on the surface of the battery cell, then put the battery cell including the insulating Mylar film into the battery aluminum shell, inject the electrolyte and then seal the battery cover. After the electrode liquid enters the battery aluminum shell, it settles at the bottom of the battery aluminum shell. Under the capillary action of the grooves 5, the electrode liquid is sucked and moves upward. Cooperating with the through holes 4 on the film body 1, side film 2 and bottom film 3, it can effectively drain the electrolyte at the bottom of the battery aluminum shell to the top of the battery cell, making the electrolyte absorption at the top and bottom of the battery more uniform, improving the infiltration effect of the battery cell. The through holes 4 arranged in an equidistant array on the film body 1, side films 2 and bottom film 3 reduce the infiltration time of the battery cell, thus effectively improving the infiltration efficiency of the battery cell. The grooves 5 are integrally formed by stamping, reducing the thickness of the insulating Mylar film and facilitating the operation of putting the battery cell into the shell.

[0022] The above are only the preferred examples of the present utility model. The technical solution of the present utility model is not limited thereto. It should be pointed out that for those of ordinary skill in the art, under the technical inspiration provided by the present utility model, as the common general knowledge in the art, other equivalent deformations and improvements can also be made, which should also be regarded as the protection scope of the present utility model.

Claims

1. A Mylar film for insulating a lithium battery cell, comprising a film body (1), side films (2) integrally formed on both sides of the film body (1), and a bottom film (3) integrally formed between two adjacent film bodies (1), characterized in that: The membrane body (1), the side membrane (2) and the bottom membrane (3) are provided with through holes (4), and grooves (5) are provided between the through holes on the membrane body (1), the side membrane (2) and the bottom membrane (3). The grooves (5) are connected to the through holes (4) on the membrane body (1), the side membrane (2) and the bottom membrane (3), and are connected to the sides of the membrane body (1), the side membrane (2) and the bottom membrane (3). The edges of the backs of the membrane body (1) and the side membrane (2) are provided with grooves (5). There is an adhesive layer (6), at least two adhesive layers (6) are provided in the middle of the back side of the membrane body (1), an easy folding mark (7) is integrally formed between the membrane body (1) and the side membrane (2), and an easy folding mark (7) is integrally formed between the membrane body (1) and the bottom membrane (3), the through holes (4) are distributed in an equidistant array on the membrane body (1), the side membrane (2) and the bottom membrane (3), the grooves (5) are arranged parallel to each other, and the grooves (5) are integrally formed by stamping.

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