CN204464327U - Heat-sealing film cutting head of a polymer lithium ion battery - Google Patents

Abstract

The utility model discloses a heat-sealing film cutting head of a polymer lithium-ion battery, which comprises a lifting cylinder, a heat-sealing pressure plate driven by the lifting cylinder, and a heat-sealing assembly fixed on the heat-sealing pressure plate; the heat-sealing assembly includes a heating block, a cutter arranged on the side of the heating block, and a detachable heat storage sheet arranged on the side of the heating block; A silicone strip is provided on the heat-sealing side of the heating block, and a boss embedded in a heat-sealing press plate is provided on the heating block. The utility model has the advantages of convenient use, flexible application, and the ability to integrate heat sealing and film cutting.

Description

Heat-sealing film cutting head of a polymer lithium ion battery

technical field

The utility model belongs to the field of battery sealing film processing equipment, in particular to a heat-sealing film cutting head of a polymer lithium-ion battery, and is especially suitable for the top-sealing welding sol of a battery with a capacity above 300Ah.

Background technique

Since the shell of the polymer lithium-ion battery is heat-sealed with aluminum-plastic film as a sealed battery shell, the aluminum-plastic film on the top of the battery must be welded together with the positive and negative tabs of the battery at high temperature, but the original device of the top sealer The sealing film indenter can only meet the aluminum-plastic film heat sealing of the battery with a layer number of 20pcs and a tab size below 280mm, and a separate cutting tool is required for the next step of cutting. When making ultra-large capacity or large-capacity batteries, the packaging conditions for making small-capacity batteries are used, that is, the pressure is 0.6Mpa, the temperature is 195±5°C, and the time is 17s. Poor air intake, liquid leakage, and corrosion caused by poor packaging of the tabs indicate that the packaging conditions for making small-capacity batteries are not suitable for making super-large or large-capacity batteries. The so-called super-large capacity refers to greater than or equal to 500AH Refers to greater than or equal to 300AH.

The solution at this stage is to prolong the heat-sealing time. Generally, the packaging time is increased to 21s. Although the packaging effect has been improved, due to the long packaging time, there is over-sealing at the non-tab and the diaphragm melts, resulting in Corrosion of the battery core and the unfavorable consequences of easy breakage at the non-tab.

In addition, when pressing down welding, the strip-shaped lower pressing plate originally conducts heat to the top of the battery for high-temperature melting welding, but in fact, part of the heat will be conducted to the main body of the battery through the positive and negative tabs, and the larger the battery capacity, the main body also The larger the battery, the larger the body, the more heat will be conducted to the battery body, and the heat will be absorbed by the battery body. Therefore, the larger the battery, the lower the top sealing welding temperature will be. In view of the above reasons, in the production The sealing film indenter that can be used for small cells can no longer be used in the production of large cells, which not only brings inconvenience to the processing of batteries with different capacities, but also takes time and effort to replace the sealing film indenter, and makes a large number of different The large or small sealing film pressure head causes waste of resources and increases the cost of production.

For the requirements of sealing and welding, the temperature should not be too low or too high. If it is too low, the welding will not work, and if it is too high, the aluminum-plastic film will become brittle due to over-melting. Therefore, the sealing and welding of large-capacity batteries cannot solve the problem of top sealing by increasing the temperature, otherwise the sol is not good and the welding is not strong in the parts with tabs, and the aluminum-plastic film will be over-melted and brittle in places without tabs, and the capacity will crack. , leading to problems such as battery leakage, gas production, and serious performance degradation in the later stage.

Utility model content

The technical problem to be solved by the utility model is to provide a heat-sealing film cutting head for high-efficiency polymer lithium-ion batteries that is easy to use, flexible in application, and integrates heat sealing and film cutting.

The utility model adopts the following technical solutions:

A heat-sealing film cutting head of a polymer lithium-ion battery, which includes a lifting cylinder, a heat-sealing platen driven by the lifting cylinder, and a heat-sealing assembly fixed on the heat-sealing platen; the heat-sealing assembly includes a heating block, arranged on The cutter on the side of the heating block and the detachable heat storage sheet arranged on the other side of the heating block; Cutting improves the efficiency of eager cutting.

As a further improvement to this solution, the heating block, the cutter and the heat storage sheet are provided with bolt holes correspondingly, the cutter is fastened to the bolt holes on the heating block by pressing bolts, and the heat storage sheet is pressed The tightening bolts are fastened with the bolt holes on the heating block.

As a further improvement to this solution, a silicone strip is provided on the side of the heating block used for heat sealing.

As a further improvement to this solution, the silica gel strip is fixed with a heating block through Teflon.

As a further improvement to the solution, the heating block is provided with a boss embedded in the heat-sealing press plate.

As a further improvement to this solution, bolt holes are correspondingly provided on the boss and the heat-sealing pressure plate, and the boss is fastened to the bolt holes on the heat-sealing pressure plate through positioning bolts.

As a further improvement to this solution, a U-shaped groove is provided at the bottom of the heating block, and the silicone strip is embedded in the U-shaped groove.

As a further improvement to this solution, the heating block is made of pure copper.

As a further improvement to this solution, the heat storage sheet is made of pure copper.

As a further improvement to this solution, the bolt holes on the side of the heating block are evenly arranged in sequence, and the bolts are fastened at multiple points in the corresponding bolt holes, which is conducive to stably fixing the heat storage sheet.

As a further improvement to this solution, the number of heat storage sheets is set according to the capacity of the battery to be heat-sealed. The larger the battery capacity, the more the number of heat storage sheets to be added on the side of the heating block. The heating surface area of the heat conduction part composed of the block and the heat storage sheet is also larger, so as to increase the heat storage capacity. When the battery capacity is small, the heat storage sheet may not be installed additionally.

As a further description of this solution, when the heat storage sheet is arranged on one side of the heat storage block, the lower edge of the heat storage sheet should be flush with the lower surface of the heat storage block.

The beneficial effects of the utility model are:

(1) The utility model is equipped with a detachable cutter on the heating block, so that the cutter is heated at the same time, making cutting easier and higher in cutting efficiency. The size of the heat-sealed head can be adjusted, which is convenient for flexible application. When it is used for small-sized batteries, it can reduce the heat storage fins, and when it is used for large-capacity batteries, it can increase the heat storage fins, that is, to achieve a The machine can be used for both small-size batteries and large-capacity batteries, saving time and effort, avoiding the need to replace the sealing film pressure head, and reducing costs at the same time.

(2) The utility model proposes that the heat sealing of the large-capacity battery no longer solves the top-sealing problem by increasing the temperature, but improves the temperature of the top-sealing position by increasing the heat storage sheet, thereby solving the problem of the top-sealing welding of the large-capacity battery. Firm, battery leakage, gas production and other problems in the later stage.

(3) The original packaging time is 21s, but the utility model only needs 17s after adding the heating block and the heat storage sheet, which shortens the hot cutting time and improves the cutting efficiency of the heat-sealing film.

(4) The heat storage sheet in the utility model is fixed to the heat storage block by means of bolt fastening, which is convenient for disassembly and assembly, and simple and easy to operate.

(5) The utility model adds a silicone strip for heat conduction, which has a certain degree of ductility after being pressed, so that the places with and without tabs are heated more evenly, and at the same time, the pressing action of the strip-shaped lower pressing plate has a certain effect. Cushioning and shock absorption.

Description of drawings

Fig. 1 is a schematic structural view of Embodiment 1 of the present utility model.

Fig. 2 is an enlarged view of part A of Fig. 1 .

Fig. 3 is a schematic structural view of Embodiment 2 of the present utility model.

FIG. 4 is an enlarged view of part B of FIG. 3 .

Among them, 1 battery, 2-1 heating block, 2-2 heat storage sheet, 2-3 cutter, 2-4 boss, 3 silicone strip, 4 compression bolt, 5 negative pole lug, 6 positive pole lug, 7 heat seal Pressing plate, 8 lifting cylinders, 9 positioning bolts. the

Detailed ways

Below in conjunction with accompanying drawing 1～4, the utility model is further described.

Referring to Figures 1-2, Embodiment 1 includes a lifting cylinder 8, a heat-sealing platen 7 pushed by the lifting cylinder 8, and a heat-sealing assembly fixed on the heat-sealing platen 7; the heat-sealing assembly includes a heating block 2-1 and a set The cutter 2-3 on the side of the heating block 2-1; the heating block 2-1 is fixed on the bottom surface of the heat-sealing platen 7, and a heating tube is arranged in the heating block 2-1, which is cut while heat-sealing , which improves eager efficiency. According to the requirement of the capacity of the battery, the heat sealing assembly may also include a detachable heat storage sheet 2-2 arranged on the side of the heating block 2-1.

As a further improvement to this solution, the heating block 2-1, the cutter 2-3 and the heat storage sheet 2-2 are correspondingly provided with bolt holes, and the cutter 2-3 is connected to the heating block 2 by pressing the bolt 4. The bolt holes on the -1 are fastened, and the heat storage sheet 2-2 is fastened to the bolt holes on the heating block 2-1 through the compression bolt 4.

As a further improvement to this solution, a silicone strip 3 is provided on the heat-sealing side of the heating block 2-1.

As a further improvement to this solution, the silica gel strip 3 is fixed with the heating block 2-1 by Teflon.

As a further improvement to this solution, the bottom of the heating block 2-1 is provided with a U-shaped groove, and the silicone strip 3 is embedded in the U-shaped groove.

As a further improvement to this solution, the heating block 2-1 is made of pure copper.

As a further improvement to this solution, the heat storage sheet 2-2 is made of pure copper.

As a further improvement to this solution, the bolt holes on the side of the heating block 2-1 are evenly arranged in sequence, and the bolts are fastened at multiple points in the corresponding bolt holes, which is conducive to stably fixing the heat storage sheet 2-2.

As a further improvement to this solution, set the number of heat storage sheets 2-2 according to the capacity of the battery to be heat-sealed. The larger the battery capacity, the more heat storage sheets 2-2 will be added on the side of the heating block 2-1. The more the number, the larger the area of the heating surface of the heat conduction part made up of the heating block 2-1 and the heat storage sheet 2-2, so as to increase the heat storage. When the battery capacity is small, it is not necessary to add Install heat storage sheet 2-2.

For further description of this solution, when the heat storage sheet 2-2 is arranged on one side of the heating block 2-1, the lower edge of the heat storage sheet 2-2 should be flush with the lower surface of the heating block 2-1.

Referring to Figures 3 to 4, Embodiment 2 is a further improvement to this solution. The heating block 2-1 is provided with a boss 2-4 embedded in the heat-sealing platen 7 .

As a further improvement to this solution, the boss 2-4 and the heat-sealing platen 7 are provided with bolt holes correspondingly, and the boss 2-4 is fastened to the bolt holes on the heat-sealing platen 7 by positioning bolts 9 .

The realization principle of the present utility model is as follows:

Utilize the heating block 2-1 to press on the surface of the battery 1 under the push of the lifting cylinder 8, and conduct the heat to the surface of the battery 1. Welded together, at this time, the cutter 2-3 on the side of the heating block 2-1 also has the force of cutting down on the aluminum-plastic film under the promotion of the lifting cylinder 8, and the aluminum-plastic film and the tabs are melted and softened due to heating. It is beneficial to cutting, heat sealing and cutting are carried out at the same time, saving time and effort, and improving the cutting effect. According to the size of the battery capacity to be heat-sealed, the quantity of the heat storage sheet 2-2 is set, the larger the battery capacity, the more the quantity of the heat storage sheet 2-2 to be increased on the side of the heating block 2-1, namely The area of the heating surface of the heat conduction part made up of the heating block 2-1 and the heat storage sheet 2-2 is also larger, so as to improve the heat storage capacity.

The polymer battery casing is heat-packed with aluminum-plastic film as a sealed battery casing. The aluminum-plastic film on the top of the battery is welded together with the positive tab 6 and the negative tab 5 of the battery at high temperature. When the equipment is welded, the lifting cylinder 8 pushes The heat-sealing platen 7 presses down. If the heat-sealing platen 7 is not used but the lifting cylinder 8 directly acts on the heating block 2-1, the hardness of the heating block 2-1 to be subjected to thrust is relatively high, but the heating The built-in heating tube of block 2-1 needs to be hollow, and the hardness should not be too high. Second, the heat of the heating block 2-1 is directly transmitted to the lifting cylinder 8. If it is heated for a long time, it will damage the lifting cylinder 8; , but heat-sealing press plate 7 with poor thermal conductivity.

There is a copper heating block 2-1 under the heat-sealing pressure plate 7, and there is a heat pipe in it. When the battery is welded, the heat-sealing pressure plate 7 with the heating block 2-1 is lowered and pressed against the aluminum-plastic film of the battery and the positive electrode ear 6. 1. On the negative electrode ear 5, make it heat-melt welded together, according to the needs of the battery capacity, install the heat storage sheet 2-2 on the side of the heating block 2-1 as required.

When welding under pressure, the heat on the heat storage block 2-1 and the heat storage sheet 2-2 will be conducted to the main body of the battery through the positive tab 6 and the negative tab 5, so that the gelling effect between the aluminum-plastic film and the tab reaches the standard.

The specific working process is as follows:

1. Add a pure copper heating block 2-1 with a length of 1200mm, a width of 40mm and a height of 15mm under the heat-sealing platen 7;

2. Put the cell of battery 1 to be heat-sealed into the punched pocket, and the size of the punching hole depends on the thickness of the cell;

3. Adjust the packaging parameters, the pressure is 0.6Mpa, the temperature is 195±5°C, and the time is 17s, front and back, each once, because the sealing film pressure head is soft-sealed when the pressure head drops, and one-time packaging can only guarantee the packaging of the upper head. effect, so the front and back sides should be packaged once. Of course, it can also be hard-sealed, but the versatility for batteries is poor, and a set of hard-sealed heads can only be fixed for one model, so the cost of producing batteries of different specifications will increase. Compared with the soft seal, it is not limited by the size of the model, so the soft seal is commonly used. Soft sealing is to make a U-shaped groove under the sealing film pressure head. The purpose is that the silicone strip 3 placed in the U-shaped groove is not easy to run, and then the silicone strip 3 and the heat-sealing pressure plate 7 are fixed tightly with Teflon;

4. Push the jig of the battery cell with battery 1 directly into the top sealing machine, press the packaging button, and the lifting cylinder 8 drives the heat sealing platen 7 and the heating block 2-1 and heat storage sheet 2-2 below it. After cutting with the cutter 2-3, the device will execute the sealing film cutting action. After the first sealing film cutting action is completed, the reverse side of the cell of battery 1 is cut the same as the first sealing film cutting, which completes the entire process. Film cutting action.

The above-mentioned implementations are only preferred embodiments of the present utility model, rather than an exhaustive list of feasible implementations of the present utility model. For those skilled in the art, any obvious changes made without departing from the principle and spirit of the utility model should be considered to be included in the protection scope of the claims of the utility model.

Claims (10)

1. a heat-sealing film crop for polymer Li-ion battery, is characterized in that: it comprises lift cylinder (8), the heat-sealing pressing plate (7) that promotes by lift cylinder (8) and the heat-sealing assembly be fixed in heat-sealing pressing plate (7); Described heat-sealing assembly comprises heat block (2-1) and is arranged on the cutting knife (2-3) of heat block (2-1) side; Described heat block (2-1) is fixed on heat-sealing pressing plate (7) bottom surface, heat-generating pipe is provided with in described heat block (2-1), described heat block (2-1) and the upper correspondence of cutting knife (2-3) are provided with bolt hole, and described cutting knife (2-3) is fastened by hold-down bolt (4) and the bolt hole on heat block (2-1).

2. the heat-sealing film crop of a kind of polymer Li-ion battery according to claim 1, is characterized in that: described heat-sealing assembly also comprises the removable heat accumulation sheet (2-2) being arranged on heat block (2-1) another side.

3. the heat-sealing film crop of a kind of polymer Li-ion battery according to claim 2, it is characterized in that: the upper correspondence of described heat accumulation sheet (2-2) is provided with bolt hole, and described heat accumulation sheet (2-2) is fastened by hold-down bolt (4) and the bolt hole on heat block (2-1).

4. the heat-sealing film crop of a kind of polymer Li-ion battery according to claim 1, is characterized in that: described heat block (2-1) is provided with silica gel strip (3) in the one side sealed.

5. the heat-sealing film crop of a kind of polymer Li-ion battery according to claim 4, is characterized in that: described silica gel strip (3) is fixed by Teflon and heat block (2-1).

6. the heat-sealing film crop of a kind of polymer Li-ion battery according to claim 1, is characterized in that: described heat block (2-1) is provided with the boss (2-4) embedding heat-sealing pressing plate (7).

7. the heat-sealing film crop of a kind of polymer Li-ion battery according to claim 6, it is characterized in that: described boss (2-4) and the upper correspondence of heat-sealing pressing plate (7) are provided with bolt hole, and described boss (2-4) is fastened by bolt (9) and the bolt hole in heat-sealing pressing plate (7).

8. the heat-sealing film crop of a kind of polymer Li-ion battery according to claim 4, is characterized in that: described heat block (2-1) bottom is provided with U-type groove, and described silica gel strip (3) is embedded in described U-type groove.

9. the heat-sealing film crop of a kind of polymer Li-ion battery according to claim 1, is characterized in that: described heat block (2-1) adopts pure copper material to make.

10. the heat-sealing film crop of a kind of polymer Li-ion battery according to claim 2, is characterized in that: described heat accumulation sheet (2-2) adopts pure copper material to make.