CN111668553A - Low-temperature soft package battery and manufacturing method thereof - Google Patents

Abstract

According to the low-temperature soft package battery and the manufacturing method thereof, the protective film, the tab suite and the winding core are arranged, in the practical application process, the positive tab is arranged at the central position of the positive plate, and the negative tab is arranged at the central position of the negative plate.

Description

Low-temperature soft package battery and manufacturing method thereof

Technical Field

The invention relates to the technical field of soft package batteries, in particular to a low-temperature soft package battery and a manufacturing method thereof.

Background

Currently, a battery refers to a device that converts chemical energy into electrical energy in a portion of the space of a cup, tank, or other container or composite container that holds an electrolyte solution and metal electrodes to generate an electric current. Has a positive electrode and a negative electrode. With the advancement of technology, batteries generally refer to small devices that can generate electrical energy. Such as a solar cell. The performance parameters of the battery are mainly electromotive force, capacity, specific energy and resistance. The battery is used as an energy source, can obtain current which has stable voltage and current, is stably supplied for a long time and is slightly influenced by the outside, has simple structure, convenient carrying, simple and easy charging and discharging operation, is not influenced by the outside climate and temperature, has stable and reliable performance, and plays a great role in various aspects of modern social life.

Batteries are a wide variety, for example, pouch batteries; as another example, a button cell; as another example, a cylindrical battery. Each type of battery has unique advantages. Just taking laminate polymer battery as an example, laminate polymer battery's a big advantage lies in taking place only can blowing at most and splitting under the condition of potential safety hazard, and this characteristic lets laminate polymer battery's security improve greatly. However, the pouch battery also has a disadvantage that the discharge performance of the pouch battery is restricted by a low-temperature condition in a low-temperature environment, which is particularly obvious in a cold winter. The reason why the soft package battery has weak discharge capacity in a low-temperature environment is mainly as follows:

firstly, because the pole piece of the existing soft package battery is usually in a belt shape, the pole piece is provided with a pole lug which is positioned at the end part of the pole piece, when the soft package battery discharges, electrons need to move from one end of the pole piece to the other end of the pole piece for discharging, the moving stroke of the electrons is equal to the total length of the pole piece, according to the law of resistance, the size of the resistance is in a direct proportion relation with the length, the longer the length is, the larger the resistance is, namely the existing soft package battery has poor electrical performance under a low-temperature environment due to the fact that the internal resistance of the existing soft package battery is large;

secondly, due to the reason of the manufacturing materials of the conventional soft package battery, the activity of the material of the soft package battery is reduced in a low-temperature environment, and the discharge performance of the soft package battery is poor under the low-temperature condition.

Aiming at the two points, the second point can greatly improve the defect of poor low-temperature discharge performance by selecting a material which can also ensure activity under the low-temperature condition to manufacture the soft package battery, however, aiming at the first point, the improvement is completed by changing the structure of the soft package battery, but no related structure exists in the prior art, and therefore, the soft package battery which can also ensure good discharge performance under the low-temperature condition is urgently needed to be developed.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide a low-temperature soft package battery and a manufacturing method thereof, wherein the low-temperature soft package battery has low internal resistance, and can ensure good discharge performance and high discharge rate in a low-temperature environment.

The purpose of the invention is realized by the following technical scheme:

a low temperature pouch cell comprising:

a protective film;

the tab assembly comprises a positive tab and a negative tab; and

roll up the core, roll up the core and include positive plate, one-level barrier film, negative pole piece and second grade barrier film, the coating has positive dry powder layer on the positive plate, positive dry powder layer is provided with just empty paper tinsel district in central point department, positive ear set up in on the just empty paper tinsel district, the coating has negative dry powder layer on the negative plate, negative dry powder layer is provided with the empty paper tinsel district of burden on central point department, the negative pole ear set up in on the empty paper tinsel district of burden, positive plate one-level barrier film negative pole piece with the second grade barrier film is piled up in proper order and is set up the banding book core area of formation, the one end of rolling up the core area is used for toward the direction of the other end of rolling up the core area is convoluteed to make banding book core area form roll up the core, roll up the core set.

In one embodiment, the width of the positive empty foil region is greater than the width of the negative empty foil region.

In one embodiment, the width of the positive empty foil area is equal to 18mm and the width of the negative empty foil area is equal to 10 mm.

In one embodiment, the positive tab has a positive positioning hole, and the negative tab has a negative positioning hole.

In one embodiment, the low-temperature soft package battery further comprises a heat conducting member, and the heat conducting member is adhered to the protective film.

In one embodiment, the heat conducting member is provided with a plurality of contact teeth at positions of the side walls, and each of the contact teeth is in close contact with the protective film.

In one embodiment, a space is provided between each two adjacent contact teeth.

In one embodiment, the protective film is provided with a hem at the location of the side wall.

In one embodiment, the protective film is an aluminum plastic film.

A manufacturing method of a low-temperature soft package battery comprises the following steps:

step S01, coating, rolling and splitting the aluminum foil in sequence to obtain a positive plate with a positive empty foil area and a negative plate with a negative empty foil area;

step S02, carrying out tab welding operation on the positive plate and the negative plate, welding the positive tab on the positive empty foil area of the positive plate, and welding the negative tab on the negative empty foil area of the negative plate;

s03, sequentially stacking the positive plate welded with the positive tab, the primary isolating film, the negative plate welded with the negative tab and the secondary isolating film to form a strip-shaped core winding belt, and winding one end of the core winding belt towards the other end of the core winding belt so that the strip-shaped core winding belt is wound to form a core;

and S04, packaging the roll core in a protective film to obtain the low-temperature soft package battery to be processed, and sequentially performing liquid injection, formation and capacity grading operations on the low-temperature soft package battery to be processed to obtain the low-temperature soft package battery.

Compared with the prior art, the invention has the following advantages and beneficial effects:

according to the low-temperature soft package battery and the manufacturing method thereof, the protective film, the tab suite and the winding core are arranged, in the practical application process, the positive tab is arranged at the central position of the positive plate, and the negative tab is arranged at the central position of the negative plate.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic structural diagram of a low-temperature pouch battery according to an embodiment of the invention;

FIG. 2 is a schematic structural diagram of a positive tab, a negative tab, a positive plate, a primary membrane, a negative plate, and a secondary membrane according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a pole piece and a tab in the prior art;

FIG. 4 is a schematic view of a portion of a transfer device according to an embodiment of the present invention;

fig. 5 is a schematic flow chart illustrating steps of a method for manufacturing a low-temperature pouch battery according to an embodiment of the present invention.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

It should be noted that, because of the advantage that the pouch battery can only blow and crack at most when a potential safety hazard occurs, the pouch battery is widely applied to various industries. While pouch batteries have many advantages, pouch batteries have disadvantages. The discharging performance of the existing soft package battery is restricted by the low-temperature environment in the low-temperature environment, the defect is particularly obvious in cold seasons or environments, and the discharging performance of the soft package battery is reduced in the low-temperature environment due to the following two reasons:

first, in the existing pouch battery, the pole piece is in a band shape, the tab is disposed at the end of the pole piece, and when the pole piece discharges, the path of the electron movement needs to move from one end of the pole piece to the other end, that is, the formation of the electron movement is equal to the total length of the pole piece. According to the law of resistance, the resistance is in a direct proportion relation with the length, and the longer the length is, the larger the resistance is, because of the structural design, the internal resistance of the existing soft package battery is larger, and when the soft package battery meets a low-temperature environment, the discharge performance of the soft package battery shows a descending trend due to the large internal resistance, so that the soft package battery cannot discharge well;

secondly, because the reason of laminate polymer battery preparation material, laminate polymer battery's material activity all can drop under low temperature environment, and then has just also leaded to laminate polymer battery not good problem under low temperature environment of stem of heart of discharging.

The two points are the reasons that the discharge performance of the soft package battery in the low-temperature environment is poor, and aiming at the second point, the soft package battery can be manufactured by adopting the material which can keep good activity in the low-temperature environment. However, in the first place, the improvement needs to be completed by changing the structure of the pouch battery itself, but there is no related structure in the prior art, and therefore, it is urgently needed to develop a pouch battery capable of ensuring good discharge performance under low temperature conditions.

In view of the above problems, please refer to fig. 1 and fig. 2 together, the present application discloses a low temperature pouch battery with low internal resistance, which can ensure good discharge performance and high discharge rate in a low temperature environment, wherein the low temperature pouch battery 10 includes a protective film 100, a tab kit 200 and a roll core 300.

Thus, it should be noted that the protective film 100 plays a role of protection; the tab kit 200 functions as an electrical connection for connection with an external device or equipment; the winding core 300 is used to store or discharge electric energy.

Referring to fig. 2, tab assembly 200 includes a positive tab 210 and a negative tab 220.

Thus, it should be noted that the positive tab 210 and the negative tab 220, the positive tab 210 is a total positive electrode of the low-temperature soft package battery 10, and is used for connecting to a total positive electrode of an external device or equipment; the negative electrode tab 220 is the total negative electrode of the low-temperature soft package battery 10 and is used for connecting with the total negative electrode of an external device or equipment.

Referring to fig. 2, the winding core 300 includes a positive plate 310, a primary isolation film 320, a negative plate 330 and a secondary isolation film 340, the positive plate 310 is coated with a positive dry powder layer 311, the positive dry powder layer 311 is provided with a positive empty foil region 311a at a central position, the positive tab 210 is disposed on the positive empty foil region 311a, the negative plate 330 is coated with a negative dry powder layer 331, the negative dry powder layer 331 is provided with a negative empty foil region 331a at a central position, the negative tab 330 is disposed on the negative empty foil region 331a, the positive plate 310, the primary isolation film 320, the negative plate 330 and the secondary isolation film 340 are sequentially stacked to form a strip-shaped winding core tape, one end of the winding core tape is used for winding toward the other end of the winding core tape, so that the strip-shaped winding core tape forms the winding core 300, and the winding core 300 is disposed in the protection film 100.

So, it should explain, because positive tab 210 sets up the central point of positive plate 310 and puts the department, negative tab 220 sets up the central point of negative plate 330 and puts the department, compare in prior art and set up utmost point ear in the tip position department of pole piece, the low temperature laminate polymer battery 10 of this application only is positive plate length and half of negative plate length at the stroke that the in-process electron removed of discharging, this structural design can greatly reduced low temperature laminate polymer battery 10's internal resistance, greatly reduced low temperature laminate polymer battery 10's whole impedance, let low temperature laminate polymer battery 10 can also possess good discharge performance under low temperature environment, can improve low temperature laminate polymer battery 10's discharge rate to a certain extent.

It should be noted that, in order to better explain the inventive concept of the present application, please refer to fig. 3, fig. 3 is a schematic structural diagram of a pole piece 20 in the prior art, as is apparent from fig. 3, a tab 21 is disposed at an end position of the pole piece 20, when the pole piece 20 needs to discharge, electrons on the pole piece 20 need to move from one end of the pole piece 20 to the other end of the pole piece 20, and a moving stroke of the electrons is equal to the total length of the pole piece 20; in contrast, when the positive plate 310 of the present application is discharged, electrons on the positive plate 310 start to move from the center of the positive plate 310, and the movement stroke of the electrons is equal to one half of that of the positive plate 310, so that the internal resistance of the low-temperature soft package battery 10 of the present application is greatly reduced, that is, the discharge rate of the low-temperature soft package battery 10 is improved, and the low-temperature soft package battery 10 can still have good discharge performance in a low-temperature environment.

It should be further noted that the primary isolation film 320 and the secondary isolation film 340 both function as insulation and isolation to prevent the positive electrode tab 310 and the negative electrode tab 330 from directly contacting to cause short circuit.

It should be noted that the positive electrode sheet 310 is coated with the positive dry powder layer 311, and the positive dry powder layer 311 is provided with a positive empty foil area 311a at the central position, where the positive empty foil area 311a is formed by an area not coated with the positive dry powder layer 311; similarly, the negative empty foil area 331a is also formed by an area not coated with the negative dry powder layer 331.

Further, in one embodiment, the width of the positive empty foil region 311a is greater than the width of the negative empty foil region 331 a.

Thus, it should be noted that the width of the positive empty foil region 311a is greater than the width of the negative empty foil region 311a, so that the width of the positive dry powder layer 311 is less than the width of the negative dry powder layer 331, and when the winding core tape is wound, the negative dry powder layer 331 of the negative electrode sheet 330 entirely covers the positive dry powder layer 311 of the positive electrode sheet 310. Specifically, the width of the positive empty foil area 311a is equal to 18mm, and the width of the negative empty foil area 331a is equal to 10 mm. As described above, the width of the positive dummy foil region 311a and the width of the negative dummy foil region 331a can be flexibly set according to actual conditions, and it is only necessary that the width of the positive dummy foil region 311a be greater than the width of the negative dummy foil region 311 a.

Further, referring to fig. 2 again, in one embodiment, the positive tab 210 has a positive positioning hole 211, and the negative tab 220 has a negative positioning hole 221. Specifically, the positive electrode positioning hole 211 and the negative electrode positioning hole 221 are both circular holes.

In this way, it should be noted that the opening of positive electrode positioning hole 211 and negative electrode positioning hole 221 can allow positive electrode tab 210 or negative electrode tab 220 to play a role of pre-positioning when an external device or equipment is connected, that is, allow positive electrode tab 210 or negative electrode tab 220 to be quickly connected with the external device or equipment.

Further, referring to fig. 1 again, in one embodiment, the low-temperature pouch battery 10 further includes a heat conducting member 400, and the heat conducting member 400 is adhered to the protective film 100.

In this way, it should be noted that the heat conducting member 400 plays a role of heat conduction, and can quickly conduct the heat inside the low-temperature pouch battery 10 to the external environment, so as to prevent the low-temperature pouch battery from being damaged due to the excessive heat accumulated inside the low-temperature pouch battery. Specifically, the heat conductive member 400 is made of a material having good heat conductivity.

Further, referring to fig. 1 again, in one embodiment, the heat conducting member 400 is provided with a plurality of contact teeth 410 on the side wall, and each contact tooth 410 is in close contact with the protective film 100.

Thus, it should be noted that, the arrangement of the plurality of contact convex teeth 410 and the plurality of contact convex teeth 410 are all in close contact with the protective film 100, which can greatly increase the contact area between the heat conducting member 400 and the protective film 100 and enhance the heat conducting performance of the heat conducting member 400. Specifically, a space is provided between each of the adjacent two contact teeth 410. Thus, it should be noted that, a space is provided between two adjacent contact convex teeth 410, and this design can prevent the two adjacent contact convex teeth 410 from interfering with each other, and can improve the heat conductivity of the heat conducting member 400 to some extent.

Further, referring to fig. 1 again, in one embodiment, the protective film 100 is provided with a hem portion 110 at a position of the sidewall.

In this way, the arrangement of the folded portion 110 can make the overall structure of the low-temperature pouch battery 10 more compact, and can reduce the overall volume of the low-temperature pouch battery 10.

Specifically, in one embodiment, the pellicle 100 is an aluminum-plastic film.

Thus, it should be noted that the protection film 100 is preferably an aluminum plastic film, and the aluminum plastic film can provide a good protection effect for the winding core 200.

In order to better understand the inventive concept of the present application, please refer to fig. 5, the present application also discloses a manufacturing method of a low-temperature soft package battery, comprising the following steps:

and step S01, coating, rolling and slitting the aluminum foil in sequence to obtain a positive plate with a positive empty foil area and a negative plate with a negative empty foil area.

In this way, first, the copper foil is coated, that is, a part of the copper foil is coated with the positive dry powder layer 311, another part of the copper foil is coated with the negative dry powder layer 331, the copper foil coated with the positive dry powder layer 311 becomes the positive electrode sheet 310, and the copper foil coated with the negative dry powder layer 331 becomes the negative electrode sheet 330. Then, rolling the positive plate 310 and the negative plate 330 to ensure uniform thickness of the positive plate 310 and the negative plate 330, and finally, splitting the rolled positive plate 310 and the rolled negative plate 330 into strips, and splitting the positive plate 310 and the negative plate 330 into strip-shaped positive plates 310 and strip-shaped negative plates 330.

It should be noted that, referring to fig. 4, in the coating operation (coating operation, i.e. coating operation), taking the coating of the positive plate 310 as an example, the application adopts that the transfer device 30 coats the negative plate 330, the transfer device is provided with a copper foil roller 31 and a material roller 32, the copper foil roller 31 is used for driving the copper foil, a trough 33 is provided right below the material roller 32, the trough 33 is used for storing the negative slurry, when the copper foil needs to be coated, the copper foil roller 31 and the material roller 32 are driven to approach each other and rotate, at this time, the material roller 32 is in contact with the copper foil, since the material roller 32 can coat the negative slurry in the trough 33 on the copper foil during the rotation of the material roller 32, the copper foil is coated with a negative dry powder layer 331, and thus the negative plate 330 is formed, since the negative dry powder layer 331 is provided with a negative empty foil area 331a at the center, a stroke sensor is further provided in the transfer device 30, and after the copper foil is transferred for a distance, the copper foil roller 31 and the material roller 32 are driven to be separated from each other, the material roller 32 is not in contact with the copper foil any more, the negative electrode slurry cannot be coated on the copper foil, and then a negative empty foil area 331a is formed, and the negative electrode sheet 330 is formed by repeating the steps, the negative dry powder layer 331 is coated on the negative electrode sheet 330 at the moment, and the negative empty foil area 331a is arranged on the central position of the negative dry powder layer 331. Since the formation of the positive electrode tab 310 is identical to the formation principle of the negative electrode tab 330, it is not repeated, except that the components of the negative electrode slurry and the positive electrode slurry are different, but the principle of coating is identical.

It should be noted that, in order to further improve the discharge performance of the negative electrode sheet 330 in a low-temperature environment, before the negative electrode sheet 330 is produced, the negative electrode slurry needs to be prepared, the solid agent of the negative electrode slurry includes graphite, a binder, a suspending agent and a conductive agent, the mass ratio of the 4 is 95.9:1.3:1.8:1, the graphite, the binder, the suspending agent and the conductive agent are introduced into the aqueous solvent, and the solid content ratio of the finally formed negative electrode slurry needs to reach 50%, that is, (graphite + binder + suspending agent + conductive agent)/(graphite + binder + suspending agent + conductive agent + aqueous solvent) — 50%, so that the weight of the aqueous solvent is calculated according to the formula. Thus, the negative electrode sheet 330 formed by coating the copper foil with the negative electrode slurry according to the above formulation has good discharge performance in a low temperature environment.

It should be noted that, in order to further improve the negative electrode sheet 330, the binder and the suspending agent may be of a low temperature type, so as to ensure that the formulated negative electrode slurry has good discharge performance at a low temperature.

Step S02, performing tab welding operation on the positive electrode tab 310 and the negative electrode tab 330, welding the positive electrode tab 210 to the positive empty foil area 311a of the positive electrode tab 310, welding the negative electrode tab 220 to the negative empty foil area 331a of the negative electrode tab 330, and performing cutting operation on the positive electrode tab 310 and the negative electrode tab 330.

In this manner, positive tab 210 is welded to positive blank foil area 311a of positive tab 310, and negative tab 220 is welded to negative blank foil area 331a of negative tab 330. In the process of welding the positive tab 210 and the negative tab 220, a welding device is used, and a blank foil sensor is disposed on the welding device, and is used for sensing the positions of the positive blank foil area 311a and the negative blank foil area 331a, taking the welding of the positive tab 210 as an example, when the blank foil sensor senses the positive blank foil area 311a, the welding device correspondingly welds the positive tab 210 on the positive blank foil area 311a, and so on.

It should be noted that, after the welding operation is completed, the positive plate 310 and the negative plate 330 need to be cut, a cutting device is used, and a cutting sensor is also arranged on the cutting device, taking the positive plate 310 as an example, the cutting sensor senses the moving stroke of the positive plate 310, and when the positive plate 310 moves to a predetermined position, the cutting of the positive plate 310 is completed by using a cutter, so as to cut the strip-shaped positive plate 310 into positive plates 310 with a certain length range.

Step S03, the positive electrode tab 310 welded with the positive electrode tab 210, the primary separator 320, the negative electrode tab 330 welded with the negative electrode tab 220, and the secondary separator 340 are sequentially stacked to form a band-shaped roll core tape, and one end of the roll core tape is wound toward the other end of the roll core tape, so that the band-shaped roll core tape is wound to form the roll core 300.

In this way, before winding, the positive electrode sheet 310, the primary separator 320, the negative electrode sheet 330 of the negative electrode tab 220, and the secondary separator 340 are stacked in this order to form a band-shaped core tape, and at this time, the core tape is wound by a winding pin, which winds one end of the core tape in the direction of the other end of the core tape, so that the band-shaped core tape is wound to form the core 300. And step S04, packaging the roll core 300 in the protective film 100 to obtain the low-temperature soft package battery to be processed, and sequentially performing liquid injection, formation and capacity grading operations on the low-temperature soft package battery to be processed to obtain the low-temperature soft package battery 10.

In this way, it should be noted that, after the winding core 300 is manufactured, the winding core 300 is packaged into the protective film 100, and the liquid injection, formation and capacity grading operations are sequentially performed on the packaged winding core 300, so as to finally obtain the low-temperature soft package battery 10.

It should also be noted that, through above steps, low temperature laminate polymer battery 10 just can be made, because positive tab 210 sets up the central point department of positive plate 310, negative pole tab 220 sets up the central point department of negative pole piece 330, compare in prior art and set up utmost point ear in the tip position department of pole piece, the stroke that the electron removed in the discharge process is only half of positive plate 310 length and negative pole piece 330 length, this structural design can greatly reduced low temperature laminate polymer battery 10's internal resistance, greatly reduced low temperature laminate polymer battery 10's whole impedance, let low temperature laminate polymer battery 10 can also possess good discharge performance under the low temperature environment, can improve low temperature laminate polymer battery 10's discharge rate to a certain extent.

The above embodiments only express a few embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (10)

1. A low temperature pouch cell, comprising:

a protective film;

the tab assembly comprises a positive tab and a negative tab; and

roll up the core, roll up the core and include positive plate, one-level barrier film, negative pole piece and second grade barrier film, the coating has positive dry powder layer on the positive plate, positive dry powder layer is provided with just empty paper tinsel district in central point department, positive ear set up in on the just empty paper tinsel district, the coating has negative dry powder layer on the negative plate, negative dry powder layer is provided with the empty paper tinsel district of burden on central point department, the negative pole ear set up in on the empty paper tinsel district of burden, positive plate one-level barrier film negative pole piece with the second grade barrier film is piled up in proper order and is set up the banding book core area of formation, the one end of rolling up the core area is used for toward the direction of the other end of rolling up the core area is convoluteed to make banding book core area form roll up the core, roll up the core set.

2. The low temperature pouch cell of claim 1, wherein the width of the positive empty foil region is greater than the width of the negative empty foil region.

3. The low temperature pouch cell according to claim 2, wherein the width of the positive empty foil zone is equal to 18mm and the width of the negative empty foil zone is equal to 10 mm.

4. The low-temperature soft package battery according to claim 1, wherein the positive tab is provided with a positive positioning hole, and the negative tab is provided with a negative positioning hole.

5. The low-temperature soft package battery according to claim 1, further comprising a heat conducting member, wherein the heat conducting member is adhered to the protective film.

6. The low-temperature soft package battery according to claim 5, wherein the heat conducting member is provided with a plurality of contact protrusions at the positions of the side walls, and each contact protrusion is in close contact with the protective film.

7. The low-temperature soft package battery according to claim 6, wherein a space is arranged between every two adjacent contact convex teeth.

8. The low-temperature soft package battery according to claim 1, wherein the protective film is provided with a flange part at the position of the side wall.

9. The low-temperature soft package battery according to claim 1, wherein the protective film is an aluminum plastic film.

10. A manufacturing method of a low-temperature soft package battery is characterized by comprising the following steps:

step S01, coating, rolling and splitting the aluminum foil in sequence to obtain a positive plate with a positive empty foil area and a negative plate with a negative empty foil area;

step S02, carrying out tab welding operation on the positive plate and the negative plate, welding the positive tab on the positive empty foil area of the positive plate, welding the negative tab on the negative empty foil area of the negative plate, and cutting the positive plate and the negative plate;

s03, sequentially stacking the positive plate welded with the positive tab, the primary isolating film, the negative plate welded with the negative tab and the secondary isolating film to form a strip-shaped core winding belt, and winding one end of the core winding belt towards the other end of the core winding belt so that the strip-shaped core winding belt is wound to form a core;

and S04, packaging the roll core in a protective film to obtain the low-temperature soft package battery to be processed, and sequentially performing liquid injection, formation and capacity grading operations on the low-temperature soft package battery to be processed to obtain the low-temperature soft package battery.

Images