CN210325968U

CN210325968U - Soft package battery

Info

Publication number: CN210325968U
Application number: CN201921629884.1U
Authority: CN
Inventors: 王培为; 王易玮; 许瑞; 徐作斌; 徐勇
Original assignee: Dongguan Huiyang Power Technology Co Ltd
Current assignee: Dongguan Huiyang Power Technology Co Ltd
Priority date: 2019-09-27
Filing date: 2019-09-27
Publication date: 2020-04-14
Anticipated expiration: 2029-09-27

Abstract

The utility model provides a laminate polymer battery, include: naked electric core, with the utmost point ear that naked electric core electricity is connected, and parcel naked electric core with the battery case of utmost point ear, utmost point ear part expose in outside the battery case, utmost point ear is provided with the cavity passageway, the cavity passageway can inject the electrolyte under vacuum state and can seal after the notes liquid finishes. Compared with the prior art, the utility model discloses design into the utmost point ear that has the cavity passageway with traditional solid utmost point ear earlier to utilize this cavity passageway to annotate the liquid, changed traditional handicraft and utilized the mode that the liquid was annotated on the air pocket limit, cancelled the setting of air pocket, need not to additionally consume auxiliary material again, structural the going improvement of battery itself annotates the liquid mode, not only effectively practiced thrift manufacturing cost, the problem that battery finished product uniformity is poor among the prior art has also been solved simultaneously, the precision of annotating the liquid and the uniformity of product have been guaranteed, the performance of product has been promoted.

Description

Soft package battery

Technical Field

The utility model relates to a laminate polymer battery field, concretely relates to laminate polymer battery.

Background

The lithium ion battery as a novel secondary battery has the advantages of large energy density and power density, high working voltage, light weight, small volume, long cycle life, good safety, environmental protection and the like, and has wide application prospect in the aspects of portable electric appliances, electric tools, large-scale energy storage, electric traffic power supplies and the like. Lithium ion batteries are mainly classified into cylindrical batteries, square batteries, and pouch batteries according to their shapes, and the cylindrical batteries and the square batteries are also called hard-shell batteries. Compared with a hard-shell battery, the soft-package battery has the advantages of flexible design, lighter weight, small internal resistance, difficult explosion, more cycle times, high energy density and the like, so that the soft-package battery occupies the market in a higher proportion in a short period and can be rapidly developed in the new energy electric automobile industry.

The soft package battery mainly comprises the following process flows: 1) stirring, coating, rolling and cutting; 2) sheet making and winding; 3) forming an aluminum plastic film and packaging by a roll core; 4) a top side sealing process; 5) liquid injection and pre-sealing; 6) a formation step; 7) vacuumizing and secondary sealing; 8) and (4) carrying out subsequent procedures such as capacity grading and the like. In the traditional preparation process, the liquid injection and vacuum pumping processes are mainly carried out in a mode of reserving an air bag, a part of unsealed aluminum-plastic film is reserved on the side edge to complete the liquid injection process, gas generated by formation is pumped out through the air bag, and redundant aluminum-plastic film is removed to complete the secondary sealing process. However, the traditional process has certain disadvantages: 1) the reserved aluminum-plastic film is removed in a secondary sealing process, so that a large amount of aluminum-plastic film is wasted; 2) a part of electrolyte can be brought out while vacuumizing, so that the reserve amount of the electrolyte in the battery cell is reduced, and the finished battery cell product has poor consistency and uneven performance; 3) the process flow is complicated, the consumed time is long, and the production efficiency is low.

To solve the above problems, chinese patent (CN208298925U) discloses a battery cell comprising: an electrode assembly; a pair of electrode leads electrically connected to the electrode assembly; a battery case for exposing a portion of the pair of electrode leads to the outside and accommodating the electrode assembly; an electrolyte inlet formed in the battery case and connectable to an electrolyte injection means for injecting an electrolyte in a vacuum state so that the electrolyte can be injected into the battery case; and an inlet cap covering the electrolyte inlet and mounted on the electrolyte inlet to be detachable from the electrolyte inlet according to a user's operation.

However, the utility model has at least the following disadvantages:

firstly, the battery liquid injection port part is exposed on the periphery of the battery in a convex manner, the obtained battery is actually a special-shaped battery, and the difference of the height, the area and the like of the convex part causes difficulty in large-scale actual production;

secondly, the inlet cap is detachable, although the operation of a user is convenient, the risk of poor sealing performance, leakage and the like exists, and the safety performance is poor.

In view of the above, it is necessary to provide a technical solution to the above problems.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a: the utility model provides a laminate polymer battery, through optimizing annotating the liquid process, solved the poor problem of battery finished product uniformity among the prior art, guaranteed the precision of annotating the liquid and the uniformity of product, promoted the performance of product, practiced thrift manufacturing cost simultaneously.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a pouch battery comprising: naked electric core, with the utmost point ear that naked electric core electricity is connected, and parcel naked electric core with the battery case of utmost point ear, utmost point ear part expose in outside the battery case, utmost point ear is provided with the cavity passageway, the cavity passageway can inject the electrolyte under vacuum state and can seal after the notes liquid finishes.

The utility model discloses a laminate polymer battery designs into traditional solid utmost point ear in advance to have the utmost point ear of cavity passageway, has cancelled the presetting on traditional air pocket limit, designs into cavity passageway business turn over from this with the notes liquid of battery and evacuation process, and this cavity passageway is as importing and exporting, compares with one side on air pocket limit as importing and exporting having reduced the area of importing and exporting greatly, the risk greatly reduced that follow-up electrolyte was taken out, the while has also avoided the harmful effects that the electrolyte offside banding that is taken out caused. Compare traditional laminate polymer battery, the utility model discloses a laminate polymer battery is owing to cancelled the setting of air pocket for the area of product effectively reduces, has reduced the occupation of land space of equipment, and the battery quantity greatly increased that the same equipment can hold has also reduced the cost of equipment. In addition, the liquid injection precision of the soft package battery and the consistency of products are greatly improved by adopting a mode of pole lug liquid injection, the service performance of the products is improved, and the situation that the difference of the electrolyte amount is very large in different batches of products is avoided.

Preferably, an electrolyte injection device is connected to the tab exposed portions so that the electrolyte is injected into the battery case. Because the opening of cavity passageway is less, it is more accurate to utilize external electrolyte injection device to introduce into electrolyte, prevents the condition of edge leakage loss electrolyte.

Preferably, the electrolyte injection device includes: the injection unit is connected to the exposed part of the lug; a vacuum unit provided to the injection unit to depressurize the inside of the battery case to a vacuum state; and the electrolyte unit is arranged on the injection unit so as to provide the electrolyte for the battery shell. Wherein, the injection unit can set up to the funnel shape, is favorable to the leading-in of electrolyte more, and vacuum unit and electrolyte unit all set up on the injection unit and communicate with it.

Preferably, the thickness of the hollow channel is 0.1-2 mm. The hollow thickness can be set according to the actual liquid injection requirement. However, if the thickness of the hollow channel is too large, since a part of the tab is connected in the case, when the thickness is too large, the battery thickness of the tab portion is too thick compared with that of the other portion, and thus there is a risk of reducing the energy density; if the thickness of the hollow part is too small, because the electrolyte liquid has surface tension, and the channel is too small, a lot of energy is consumed to drive the electrolyte to enter the battery shell. Therefore, it is preferable to maintain the hollow thickness within this range.

More preferably, the hollow thickness of the tab is 0.5 to 1.5 mm.

Preferably, the width of the tab is 5-120 mm, and the overall thickness of the sealed tab is 0.1-2 mm. The width of the tab can be die-cut according to the sizes of different battery cores, the whole thickness of the sealed tab is approximately similar to the thickness of the tab before the hollow channel is not arranged in the initial manufacturing process, and the thickness of the final tab is not changed due to the arrangement of the hollow channel.

Preferably, the tab is including setting up positive tab and negative pole ear at naked electric core both ends, positive tab part expose in battery case one end, negative pole ear part expose in battery case's the other end, wherein, hollow channel set up in positive tab and/or negative pole ear. Set up positive pole ear and negative pole ear respectively at the both ends of naked electric core, so can increase the width of utmost point ear, enlarge the area of cavity passageway on the whole to do benefit to subsequent notes liquid process. Of course, a hollow channel can be arranged on both the positive electrode tab and the negative electrode tab, and the two sides can be used for injecting liquid simultaneously, so that the liquid injection time is shortened.

Preferably, utmost point ear is including setting up positive pole ear and negative pole ear of the same end of naked electric core, positive pole ear with the negative pole ear all expose in battery case's same end, wherein, the cavity passageway set up in positive pole ear and/or negative pole ear. The positive tab and the negative tab are arranged at the same end, so that the subsequent preparation of the soft package battery is facilitated.

Preferably, the hollow passage is a kidney-shaped hole. The hollow channel is arranged to be in a waist-shaped channel shape, so that the channel area can be increased to a greater extent, and the injection of electrolyte is facilitated.

Compared with the prior art, the utility model discloses following beneficial effect has at least:

1) the utility model provides a laminate polymer battery, include: naked electric core, with the utmost point ear that naked electric core electricity is connected, and parcel naked electric core with the battery case of utmost point ear, utmost point ear part expose in outside the battery case, utmost point ear is provided with the cavity passageway, the cavity passageway can inject the electrolyte under vacuum state and can seal after the notes liquid finishes. Compared with the prior art, the utility model discloses design into hollow utmost point ear with traditional solid utmost point ear earlier, through set up the cavity passageway in utmost point ear, utilize this cavity passageway to annotate the liquid, changed traditional technology and utilized the mode that the liquid was annotated on the air pocket limit, cancelled the setting of air pocket, effectively reduced battery case's use cost, accomplish again after annotating the liquid with utmost point ear sealed recovery into traditional solid utmost point ear, the original function of performance utmost point ear. This annotate liquid mode need not additionally to consume auxiliary material again, goes to improve in battery own structure and annotates the liquid mode, has not only effectively practiced thrift manufacturing cost, has also solved the poor problem of battery finished product uniformity among the prior art simultaneously, has guaranteed the precision of annotating the liquid and the uniformity of product, has promoted the performance of product.

2) The utility model has simple preparation process, simplifies the packaging process and saves time for the whole process; additionally, because the utility model discloses the setting of cancellation air pocket, the harmful effects that electrolyte caused the banding when having avoided the secondary banding.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Fig. 2 is a partially enlarged view of a portion a in fig. 1.

Fig. 3 is a schematic view of the liquid injection structure of the present invention.

In the figure: 1-naked electric core; 2-pole ear; 21-a hollow channel; 3-a battery case; 4-electrolyte injection means; 41-an injection unit; 42-a vacuum unit; 43-electrolyte cell.

Detailed Description

In order to make the technical solutions and advantages of the present invention clearer, the present invention and its advantageous effects will be described in further detail below with reference to the accompanying drawings of the detailed description and the specification, but the present invention is not limited thereto.

As shown in fig. 1 to 3, a pouch battery includes: naked electric core 1, with the utmost point ear 2 that naked electric core 1 electricity is connected to and the battery case 3 of naked electric core 1 of parcel and utmost point ear 2, utmost point ear 2 part expose outside battery case 3, and utmost point ear 2 is provided with hollow channel 21, and hollow channel 21 can inject the electrolyte under vacuum state and can be sealed at notes liquid back pressfitting that finishes. Each accessory of this laminate polymer battery can refer to current laminate polymer battery, and the utmost point ear 2 before this laminate polymer battery annotates the liquid and accomplishes is utmost point ear 2 for having hollow passage 21 to do benefit to electrolyte and get into battery case 3 from this hollow passage 21 in, accomplish the preliminary preparation of battery. After the battery liquid injection is finished, the tab 2 is sealed, and the tab 2 still plays a main role of conducting electricity in the battery as the tab 2 in the prior art when the subsequent battery works.

Wherein, the tab 2 can be obtained by punching and/or drawing the tab 2 with the hollow channel 21. The thickness of the hollow channel 21 is 0.1-2.0 mm, the width of the tab 2 is 5-120 mm, and the whole thickness of the sealed tab 2 is 0.1-2 mm. Preferably, the thickness of the hollow channel 21 is 0.5-1.5 mm. In addition, utmost point ear 2 includes anodal ear and negative pole ear, can set up anodal ear and negative pole ear respectively at naked electric core 1's both ends, also can all set up anodal ear and negative pole ear in naked electric core 1 same end, specifically can select according to the size and the actual need of preparation battery.

In addition, the soft package battery is also externally connected with an electrolyte injection device 4 during liquid injection, the electrolyte injection device 4 is connected with the exposed part of the tab 2 and comprises an injection unit 41, and the injection unit 41 is connected with the exposed part of the tab 2 and matched with the hollow channel 21; a vacuum unit 42 provided on and communicating with the injection unit 41 to depressurize the inside of the battery case 3 to a vacuum state; and an electrolyte unit 43, the electrolyte unit 43 being disposed at the injection unit 41 and communicating therewith to supply the electrolyte to the battery case 3. The injection unit 41 may be configured in a funnel shape, which is more advantageous for introducing the electrolyte. The electrolyte injection device 4 is also connected with a driving device which is respectively electrically connected with the vacuum unit 42 and the electrolyte unit 43 and can provide pressure to send the electrolyte into the battery shell during electrolyte injection; when evacuation, utilize power to take out the gas in the battery for battery case 3's inside decompression is to the vacuum state, in order better to accomplish subsequent processes such as notes liquid and formation.

The preparation process of the soft package battery comprises the following steps:

s1, arranging the bare cell 1 and the tab 2 in the battery shell 3 with the punched pit, wherein the bare cell 1 is electrically connected with the tab 2, and a part of the tab is exposed out of the battery shell 3; then, heat sealing is carried out on the periphery of the battery shell 3, and the heat sealing pressure of the top of the battery shell 3 needs to be kept smaller than the pressure of the subsequent lamination sealing of the tab 2, so that the hollow channel 21 of the tab 2 is prevented from being sealed by overlarge heat sealing pressure of the top of the battery shell 3; of course, a hot pressing tool matched with the top of the battery shell 3 can be adopted to avoid the position of the lug for hot pressing;

s2, after heat sealing, connecting the electrolyte injection device 4 to the exposed part of the tab 2, matching the injection unit 41 of the electrolyte injection device 4 with the hollow channel 21 of the tab 2, depressurizing the inside of the battery case 3 to a vacuum state by the vacuum unit 42 of the electrolyte injection device 4, and then flowing the prepared electrolyte from the electrolyte unit 43 to the injection unit into the battery case 3 through the hollow channel 21;

s3, standing for a period of time after liquid injection, fixing the tab 2 by using a clamp tool, then pressing and welding the tab 2 by using external force to complete sealing, and if the top sealing pressure is too low and is only simple sealing, secondary top sealing can be performed again; the external force comprises one or more of laser welding, ultrasonic welding and fixture hot pressing, and no matter what sealing mode is adopted, the inside of the tab 2 is ensured to be in a sealing state, and the subsequent normal use of the tab 2 is not influenced;

and S4, placing the sealed battery into formation equipment for formation, then vacuumizing to lead out gas generated by formation, and finally performing capacity grading test to finish the manufacture of the battery. The evacuation in this step can be performed through another fluid infusion port or another opening, instead of through the hollow channel 21 of the tab 2. Of course, the hollow channel 21 of the tab 2 may be used for processing, but at this time, a component easy to close needs to be added at the exposed position of the tab 2, after the liquid injection of the tab 2 is completed, the tab 2 is simply sealed to complete the formation process, after the formation process is completed, the gas generated by formation is extracted by opening the tab 2, and finally, the tab 2 is pressed and welded. The method can also finish the preparation of the soft package battery.

Compared with the prior art, the utility model provides a tab with hollow channel first, carry out the priming by this hollow channel, changed traditional priming mode, given the tab new function that can be used for the priming simultaneously, this priming mode has cancelled the setting of air pocket, has not only reduced the use cost of battery case and the volume of product reduces, has reduced equipment cost, has also reduced the occupation of land space of equipment; meanwhile, the liquid injection mode solves the problem of poor consistency of finished battery products in the prior art, ensures the precision of liquid injection and the consistency of products, and improves the service performance of the products; in addition, the preparation process of the soft package battery obtained by the liquid injection mode is reduced, and the sealing process is simpler.

Variations and modifications to the above-described embodiments may become apparent to those skilled in the art from the disclosure and teachings of the above description. Therefore, the present invention is not limited to the above-mentioned embodiments, and any obvious modifications, replacements or variations made by those skilled in the art on the basis of the present invention belong to the protection scope of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

1. A pouch cell, comprising: naked electric core, with the utmost point ear that naked electric core electricity is connected, and parcel naked electric core with the battery case of utmost point ear, utmost point ear part expose in outside the battery case, utmost point ear is provided with the cavity passageway, the cavity passageway can inject the electrolyte under vacuum state and can seal after the notes liquid finishes.

2. The pouch battery according to claim 1, wherein an electrolyte injection device is connected to the tab exposed portion so that the electrolyte is injected into the battery case.

3. The pouch cell according to claim 2, wherein the electrolyte injection device comprises:

the injection unit is connected to the exposed part of the lug;

a vacuum unit provided to the injection unit to depressurize the inside of the battery case to a vacuum state;

and the electrolyte unit is arranged on the injection unit so as to provide the electrolyte for the battery shell.

4. The laminate battery according to claim 1, wherein the thickness of the hollow channel is 0.1-2 mm.

5. The laminate battery according to claim 4, wherein the thickness of the hollow channel is 0.5-1.5 mm.

6. The laminate polymer battery according to claim 1, wherein the tab has an overall thickness of 0.1-2 mm after being sealed, and a width of 5-120 mm.

7. The soft package battery of claim 1, wherein the tabs comprise a positive tab and a negative tab disposed at two ends of the bare cell, and wherein the hollow channel is disposed at the positive tab and/or the negative tab.

8. The laminate battery according to claim 1, wherein the tab comprises a positive tab and a negative tab disposed at the same end of the bare cell, and wherein the hollow channel is disposed at the positive tab and/or the negative tab.

9. The pouch cell according to claim 1, wherein the hollow channel is a kidney-shaped tunnel.