CN110707366A

CN110707366A - Production method of polymer soft package battery

Info

Publication number: CN110707366A
Application number: CN201910947579.5A
Authority: CN
Inventors: 宋理; 危奕; 钱学兵; 雷娟
Original assignee: Shenzhen Asa Precision Electric Co Ltd
Current assignee: Shenzhen Asa Precision Electric Co Ltd
Priority date: 2019-09-30
Filing date: 2019-09-30
Publication date: 2020-01-17

Abstract

The invention discloses a production method of a polymer soft package battery, which synchronously exhausts gas in a formation process and comprises the following steps: firstly, feeding a battery cell to a feeding device; secondly, moving the battery cell to a hot-pressing formation device; thirdly, clamping the battery cell and preparing for opening formation; (IV) carrying out opening formation; fifthly, transferring the battery cell to a blanking device; sixthly, transferring the battery cell to a secondary edge trimmer; (seventhly) forming the battery cell; and (eighthly), moving the battery cell to the next procedure. In the production process of the battery, the formation process is synchronously exhausted, so that the equipment investment cost of separate treatment is reduced, the formation time is shortened, and the production efficiency is improved.

Description

Production method of polymer soft package battery

Technical Field

The invention relates to the technical field of battery production, in particular to a production method of a polymer soft package battery.

Background

The development of production technology is better and better, people have more and more rigorous utilization of time, and in life, the lithium ion secondary battery is used as a green environment-friendly battery, and is applied to a plurality of applications on the basis of the national strong advocation of environment protection and new energy cleaning in recent years, particularly to the application of new energy automobiles. The increase and the expansion of battery application field just have to impel battery producer to simplify the production procedure, shorten process time and improve production efficiency in order to satisfy market demand, make it exert the biggest value, along with the development of science and technology, polymer laminate polymer battery production mode has had development of to a great extent and has brought very big facility for people in polymer laminate polymer battery production.

The production and manufacturing of the lithium ion battery are processes strictly connected by process steps, in the whole, the production of the lithium ion battery comprises a pole piece manufacturing process, a battery assembling process and a final liquid injection, sealing, formation and aging process, in the processes of the three stages, each process has a plurality of key processes, each step can greatly influence the final performance of the battery, and after the sealed battery cell is completed, the formation is needed, namely, the manufactured lithium ion battery is charged and discharged by small current for one time.

After the battery is manufactured, the electrode material is not in an optimal usable state or the physical properties are not appropriate. For example, the particles are too large, the contact is not tight or the phases are not themselves in register. For example, metal oxide cathodes, which are some alloying mechanisms, require a first charge-discharge to activate them. In the process of first charging of a lithium battery, Li < + > is extracted from an anode active substance and is embedded between negative electrode graphite material layers after passing through an electrolyte, a diaphragm and the electrolyte, electrons are transferred from an anode to a cathode along a peripheral circuit, at the moment, the electrons are embedded into the graphite cathode at a lower potential and react with the electrolyte to generate an SEI film and partial gas, the partial gas is generated in the process and is consumed along with a small amount of electrolyte, and some battery manufacturers can perform battery exhaust and liquid supplement operations after the process, particularly for a titanic acid battery, the generated gas can generate a large amount of gas to cause the battery bulge to be more than 10% thick.

The battery exhaust process after formation is a key process in the formation process, most battery manufacturers independently exhaust after the charging and discharging processes, the whole formation process adopting low-current formation has long time, and the liquid injection hole must be sealed and sealed in the process to prevent the electrolyte from being gasified and lost in the high-temperature and high-pressure process for a long time. Because lithium ion is sensitive to water, in the process of manufacturing the battery, a small amount of moisture exists in the pole piece or the electrolyte, a large amount of gas is generated in the formation process, the gas cannot be discharged in the closed battery, and after the gas generated in the formation process is completely formed, the liquid injection hole needs to be opened to exhaust the gas, and then the gas is sealed again, so that the production efficiency is low.

For the hot pressing formation process after the injection of the lithium ion battery, the prior art generally adopts the process method as shown in fig. 1 and fig. 2, and the process in fig. 1 is as follows: the method comprises the steps of front-stage process, formation, exhaust, secondary sealing, edge cutting, volume grading and subsequent process. The process in fig. 2 is: the method comprises the steps of front-stage process, formation, volume grading, exhaust, secondary sealing, trimming and subsequent process. The formation process and the exhaust process of the two process methods are separately carried out and different equipment or tool fixtures are adopted, so that the equipment investment is high, the formation time is long, and the production efficiency is low.

Disclosure of Invention

Aiming at the defects of the prior art, the invention solves the technical problems that the formation-exhaust process is separated in the production process of the battery, so that the equipment investment cost is high, the formation time is long, and the production efficiency is low.

In order to solve the technical problems, the technical scheme adopted by the invention is a production method of a polymer soft package battery, wherein the gas is synchronously exhausted in the formation process, and the production method comprises the following steps:

feeding a battery cell to a feeding device, and manually placing the battery cell pre-sealed by liquid injection into a clamp moving frame of the feeding device;

moving the battery cell to a hot-pressing formation device, moving a clamp moving frame of a feeding device from a first feeding station to a second feeding station of the feeding device, and grabbing the battery cell in the clamp moving frame by a transfer manipulator to load the battery cell to the hot-pressing formation device;

thirdly, clamping the battery cell and preparing for opening formation, clamping the battery cell body by a cold and hot pressing clamp of the hot pressing formation device, and adsorbing and clamping the battery cell air bag by the opening formation and exhaust integrated device;

opening formation is carried out, and the opening formation and exhaust integrated device starts to carry out opening formation working procedure work;

transferring the battery cell to a blanking device, opening a cold and hot pressing fixture in the hot pressing device, transferring the battery cell on the cold and hot pressing fixture to a fixture moving frame at a first blanking station in the blanking device by using a transferring manipulator, and then moving the fixture moving frame from the first blanking station to a second blanking station;

the battery cell is transferred to a second sealing edge trimmer, and the four-axis manipulator transfers the battery cell on the clamp moving frame in the second blanking station to the second sealing edge trimmer in sequence;

seventhly, forming the battery core, finishing secondary sealing of the battery core air bag by a secondary sealing edge trimmer, cutting off the air bag, and forming the battery core;

and (eight) moving the battery cell to the next procedure, manually placing the formed battery cell in the transfer frame, and transferring to the next procedure of the battery cell.

In the step (iv), the opening formation includes the following sub-steps:

(1) electrifying the formation, controlling a hot-pressing formation clamp to switch on a battery cell formation charging and discharging power supply through a central control unit, charging the battery cell for the first time, and starting the formation process of the battery cell;

(2) the air bag is adsorbed, the opening formation and exhaust integrated device generates preset negative pressure in a sucker cavity of the air bag, and a sucker bell mouth is tightly adsorbed on the side surface of the air bag of the battery core;

(3) puncturing the air bag, starting a pneumatic component in the opening and exhaust integrated device to work and input compressed air, pushing a bayonet mechanism to act by the compressed air, and puncturing the electric core air bag adsorbed by the sucker by the bayonet in the cavity of the sucker;

(4) forming a battery core, starting a charging process by a hot pressing forming process, and leading out gas generated in the battery forming process through a puncture hole, the gas passes through a sucker cavity and a suction hole of an opening forming and exhausting integrated device under the action of constant negative pressure in the sucker cavity;

(5) after the formation is finished and the whole hot-pressing formation process is finished, the central control unit disconnects the charging and discharging power supply of the battery cell;

(6) sealing the puncture, wherein the puncture of the battery cell air bag is sealed by an opening formation and exhaust integrated device;

the sealing operation is a hot-press sealing operation or a glue-spraying sealing operation.

The hot pressing sealing operation is to clamp the battery cell air bag through two heat-sealing frames, heating wires are arranged in the heat-sealing frames, and the heat-sealing frames are heated to a preset temperature to seal the battery cell air bag around the puncture hole in a sealing manner.

The glue spraying and sealing operation is that a silica gel nozzle is arranged in a sucker cavity of the integrated device with opening formation and exhaust, and after the formation is finished, the nozzle sprays special glue to seal the periphery of a puncture hole.

(7) The air pressure is balanced, and the negative pressure device stops working to ensure that the air pressure in the cavity of the sucker of the opening forming and exhausting integrated device is consistent with the external air pressure;

(8) standing and grading the capacity, and standing and grading the battery;

(9) the clamp is opened and is pressed from both sides, and cold and hot pressure clamp is opened simultaneously and is become and the sucking disc of the integrative device of exhaust leaves electric core air pocket.

Compared with the prior art, the invention synchronously exhausts in the formation process in the production process of the battery, reduces the equipment investment cost of separate treatment, shortens the formation time and improves the production efficiency.

Drawings

FIG. 1 is one of the prior art flow diagrams;

FIG. 2 is a second flowchart of the prior art;

FIG. 3 is a schematic diagram of a production line of polymer soft package batteries;

FIG. 4 is a front view of the integrated vent forming and venting device;

FIG. 5 is a rear view of the structure of the integrated vent formation and venting device;

FIG. 6 is an exploded view of the integrated device for forming the opening and exhausting gas;

FIG. 7 is a schematic view of the bayonet mechanism, the front seat and the suction cup;

FIG. 8 is a schematic structural view of a multi-group opening formation and exhaust integrated device;

FIG. 9 is a schematic view of a spray sealing mechanism;

FIG. 10 is a schematic structural view of a feeding device;

fig. 11 is a schematic structural diagram of a cell clamp of the feeding device;

FIG. 12 is a schematic structural view of a transfer robot;

FIG. 13 is a schematic view of the guard structure;

FIG. 14 is a flow chart of the present invention;

fig. 15 is a flow chart of the opening formation.

Detailed Description

The following further describes the embodiments of the present invention with reference to the drawings, but the present invention is not limited thereto.

Fig. 1 is one of the processes of the prior art, and the process comprises: the method comprises the steps of front-stage process, formation, exhaust, secondary sealing, edge cutting, volume grading and subsequent process.

Fig. 2 shows a second process of the prior art, which comprises the following steps: the method comprises the steps of front-stage process, formation, volume grading, exhaust, secondary sealing, trimming and subsequent process.

Fig. 3 is a laminate polymer battery production synthesis production line, including frame 1, loading attachment 2, hot briquetting device 3, unloader 4, move and carry manipulator 5, four-axis manipulator 6 and two bead cutters 7, loading attachment 2, hot briquetting device 3, unloader 4, four-axis manipulator 6 and two bead cutters 7 are technology-connected in proper order, loading attachment 2, hot briquetting device 3, unloader 4 top are frame 1, move and carry manipulator 5 and the track cooperation that is equipped with in the frame 1 and move the electric core in loading attachment 2 and carry to hot briquetting device 3 and carry out the formation, move again and carry to carry out two and seal the side cut and take shape by four-axis manipulator 6 to two bead cutters 7 in unloader 4.

At least one thermal compression forming device 3.

The hot pressing device 3 comprises a cold and hot pressing clamp 31, an opening forming and exhausting integrated device 32, a charging and discharging power supply 33 and a negative pressure system, at least 2 laminated boards 311 are arranged in the cold and hot pressing clamp 31, the opening forming and exhausting integrated device 32 is arranged at the top of the laminated boards 311 and communicated with the negative pressure system, the charging and discharging power supply 33 and the negative pressure system are both arranged below the cold and hot pressing clamp 31, and the charging and discharging power supply 33 is electrically connected with the cold and hot pressing clamp 31.

As shown in fig. 4 to 7, the opening formation and exhaust integrated device 32 includes a front section 321, a rear section 322 and a sealing mechanism 323, the sealing mechanism 323 is separately disposed on the opposite end faces of the front section 321 and the rear section 322, the front section 321 includes a front seat 3211, a suction cup 3212 and a bayonet mechanism, the suction cup 3212 is mounted on the end face of the front seat 3211, the bayonet mechanism is mounted on the front seat 3211 and penetrates out of the suction cup 3212 and the sealing mechanism 323, the front seat 3211 is provided with an air inlet 32111 and an air outlet 32112, the front section 321 and the rear section 322 move in opposite directions in a split structure, the bayonet mechanism operates to puncture the battery cell air bag, and then the battery air bag punctures the peripheral sealing of the port by the sealing mechanism 323 after vacuum air is extracted by the air outlet 32112, thereby achieving the purposes of opening formation, exhaust and sealing.

As shown in fig. 8, the front section 321 is disposed on the top of one laminated board 311 disposed in the hot and cold pressing jig 31, the rear section 322 is disposed at a position corresponding to the top of the adjacent laminated board 311, and another front section 321 is disposed beside the adjacent laminated board 311, and the rear section 322 is disposed at a position corresponding to the top of the next adjacent laminated board 311, and so on, to form a plurality of sets of the integrated device 32 for opening formation and exhaust.

As shown in fig. 4 to 6, the front seat 3211 has an air inlet 32111 and an air exhaust port 32112 formed on a side surface thereof, a front surface thereof is hermetically connected to the suction cup 3212, an air duct 32113 formed on an end surface of the sealing area is communicated with the air exhaust port 32112, a lower platform and an upper platform formed on a back surface thereof, a through hole formed in a center of the lower platform, and an air groove formed on a surface of the upper platform and communicated with the air inlet 32111.

As shown in fig. 7, the bayonet mechanism includes a bayonet 32131, a sliding sleeve 32132, a spring 32133, a piston 32134, a countersunk screw thread 32135, and a cover plate 32136, the sliding sleeve 32132 is fixedly sleeved in a through hole formed in a lower sinking platform formed in the front seat 3211, the bayonet 32131 is a cylinder with a bayonet head at a front end, a threaded hole is formed at a rear end of the cylinder, the piston 32134 is clamped between the spring 32133, the countersunk screw thread 32135 connects the piston 32134 with the threaded hole at the rear end of the bayonet 32131, two ends of the spring 32133 respectively abut against the sliding sleeve 32132 and the cover plate 32136, the cover plate 32136 covers the upper sinking platform formed at a rear surface of the front seat 3211, and an air flow groove is formed at a periphery of the piston 32134 to allow compressed air to drive the piston 32134 to drive the bayonet 32131.

The sealing mechanism 323 can be a heat sealing mechanism or a jet sealing mechanism.

The heat sealing mechanism comprises a front sealing frame 3231, a rear sealing frame 3232 and heating wires, the front sealing frame 3231 and the rear sealing frame 3232 are respectively arranged at the corresponding ends of the front section part 321 and the rear section part 322, and the heating wires are respectively arranged in the front sealing frame 3231 and the rear sealing frame 3232 so as to heat the heat sealing frames to a certain temperature in a short time to perform pre-sealing work of the battery cell air bag.

As shown in fig. 9, the bottom of the original front seat 3211 and the bottom of the original back seat 3221 of the injection sealing mechanism are both provided with a sealing glue interface 324, the sealing glue interface 324 is connected with an L-shaped elbow, the opening of the L-shaped elbow is connected with a sealing glue needle 325, the sealing glue needle 325 is curved with an arc, the needle is located below the puncture opening 326 of the bayonet by a distance of about 5mm, and the needle is inclined upwards by about 30 degrees to ensure that the glue 9 sprayed from the needle can fully cover the puncture opening 326 of the bayonet, thereby enhancing the reliability of the puncture opening 326 sealed by the glue 9.

As shown in fig. 6, the rear section 322 includes a rear seat 3221, and the rear seat 3221 is disposed on the back of the rear cover frame 3232.

In order to effectively insulate the rear sealing frame 3232, as an improvement of the present invention, the present invention further includes a heat insulation board 3222, and the heat insulation board 3222 is disposed between the rear sealing frame 3232 and the rear seat 3221.

In order to ensure that the bayonet 32131 quickly exhausts air to the air bag penetration effect of the battery cell, as an improvement of the invention, the invention further comprises a stop block 3223, wherein the end face of the stop block 3223 corresponding to the bayonet 32131 is provided with a bayonet counter bore 231 and is arranged between the rear sealing frame 3232 and the heat insulation plate 3222 in an attaching manner.

As shown in fig. 3 and 10, the feeding device 2 includes a clamp moving frame 21, a rail 22 and a central control unit 23, working surfaces of the clamp moving frame are divided into a first feeding station 24 for manual feeding and a second feeding station 25 for loading and unloading by the transfer robot 5, the rail 22 spans the first feeding station 24 and the second feeding station 25, the central control unit 23 is arranged below the second feeding station 25, a motor-driven synchronous belt 26 is arranged below the clamp moving frame 21, guide plates 27 are arranged at two ends of the motor-driven synchronous belt 26 and are in sliding contact with the rail 22, a cell clamp 28 is arranged on the surface of the clamp moving frame 21, and the battery clamp is driven by the lower synchronous belt 26 to reciprocate between the first feeding station 24 and the second feeding station 25 through the sliding contact between the guide plates and the rail 22.

As shown in fig. 11, the cell holder 28 includes an inner frame 281, a fixing plate 282, a plurality of lamination plates 283 and a motor 284, wherein slide rails are disposed on two inner sides of the inner frame 311, slide blocks matched with the slide rails are disposed on two ends of the fixing plate 282 and the lamination plates 283, and the motor drives the lamination plates 283 to move on the slide rails.

As shown in fig. 3, in order to prevent the manual operation from entering the dangerous area of the second loading station 25 to cause an injury accident when the transferring manipulator 5 transfers the battery cell at the second loading station 25, an automatic screen door 29 is provided between the first loading station 24 and the second loading station 25, and an early warning device is provided. When the transfer robot 5 takes the material at the second loading station 25, the automatic screen door 29 is automatically closed.

The blanking device 4 has the same structure as the feeding device 2 and is also divided into a first blanking station 41 and a second blanking station 42, the transferring manipulator 5 places the battery cell on the fixture moving frame 21 of the first blanking station 41, and the fixture moving frame 21 is moved from the first blanking station 41 to the second blanking station 42 so that the four-axis manipulator 6 can take out the battery cell 8.

The frame 1 is an integrated frame, the front end and the rear end of the integrated frame cover the space between the second feeding station 25 of the feeding device 2 and the upper part of the first blanking station 41 of the blanking device 4 respectively, and the two ends of the integrated frame are provided with rack rails 11.

As shown in fig. 12, the transfer robot 5 has a square frame, and includes a gripper 51, a traverse servo motor 52 and a vertical servo motor 53, the traverse servo motor 52 and the vertical servo motor 53 are both disposed on the square frame, the gripper 51 is disposed below the square frame, gears 54 are disposed on both sides of the square frame to engage with the rack rails 11 of the rack 1 for transmission, the traverse servo motor 52 drives the transfer robot 5 to move back and forth, and the vertical servo motor 53 drives the gripper 51 to move up and down through a screw rod. The number of the clamping jaws 51 is the same as the number of the cells which can be loaded at one time by the clamp moving frame 21 of the loading device 2, the cold and hot pressing clamp 31 and the clamp moving frame 21 of the unloading device 4.

Further, as shown in fig. 13, in order to prevent the clamping jaws 51 from dropping the battery cell due to an error in the clamping action during the transferring process of the battery cell, as a further improvement of the present invention, a protection device is disposed below the clamping jaws 51, the protection device is a frame structure, a folding protective net 56 is disposed at the bottom of the protection device, two ends of the folding protective net are both provided with slide blocks 57 and rodless cylinders 58 engaged with the slide blocks, and the rodless cylinders drive the folding protective net to extend or retract. After the clamping jaws 51 grab the battery cells, the protective net is unfolded and closed, and the battery cells accidentally dropped from the clamping jaws 51 during the moving process of the transfer manipulator 5 fall on the protective net.

Further, in order to accurately detect the falling of the battery cell, as a further improvement of the present invention, at least one correlation photoelectric sensor is further disposed below the clamping jaw 51 and outside the projection range of the battery cell to warn the falling of the battery cell.

The four-shaft mechanical arm 6 is arranged between the blanking device 4 and the two edge cutting machines 7 and is responsible for grabbing the battery cell 8 on the clamp moving frame 21 of the blanking device 4 onto the two edge cutting machines 7.

The secondary edge trimmer 7 is in charge of secondary sealing and edge trimming of the battery cell in the prior art.

The working principle of the invention is as follows:

when production is started, a manufacturer places the battery cell 8 on the battery cell clamp 28 of the clamp moving frame 21 in the feeding device 2 at the first feeding station 24, the air bag of the battery cell 8 faces upward, the battery cell clamp 28 positions the battery cell 8 through the fixing plate 282 and the plurality of laminated plates 283, then the clamp moving frame 21 moves from the first feeding station 24 to the second feeding station 25, and the transferring manipulator 5 starts to operate to take out the battery cell 8 from the battery cell clamp 28 and move the battery cell 8 to the cold and hot pressing clamp 31 in the hot pressing device 3 for opening formation and exhausting processes. After the clamp moving frame 21 enters the second feeding station 25, the transfer robot 5 starts to operate, and the automatic screen door 29 is automatically closed.

When the exhaust process is started, the front-stage member 321 and the rear-stage member 322 in the opening formation and exhaust integrated device 32 move to a predetermined position in opposition to each other. At this time, the suction cup 3212 is brought into close contact with the stopper 3223 to hold the air bag, and the air bag is brought into close contact with the front-stage member 321 and the rear-stage member 322 by the negative pressure communicated through the negative pressure port. When compressed air enters the front seat 3211 through the air inlet 32111, compressed air flow is collected between the cover 32136 and the piston 32134 by the air flow grooves on the piston 32134, so that the piston 32134 pushes the bayonet 32131 to pierce the bayonet counter bore 231 in the stopper 3223 of the rear section 322, completing the air bag piercing action. After the piercing is completed, the compressed air stops supplying air, the bayonet 32131 retracts under the action of the return of the spring 32133, and the air in the air bag is continuously sucked out by the suction cup 3212. When the heat sealing mechanism is used for sealing, the front sealing frame 3231 and the rear sealing frame 3232 start to be preheated before formation is finished, and when the temperature reaches a specified temperature, the front sealing frame 3231 moves towards the rear sealing frame 3232, the air bag is pressed, and a puncture is sealed in advance. After several seconds, the front sealing frame 3231 returns to its original position, the heating is stopped, the vacuum is turned off, the front section 321 and the rear section 322 return to their original positions at the same time, and the exhaust is completed. When the injection sealing mechanism is used for sealing, the sealing glue needle 325 sprays glue 9 to cover the puncture opening 326 of the bayonet while the bayonet pierces the air bag of the battery cell 7, and after formation, the puncture opening 326 is pressed and attached to the rear part 322 through the front part 321 to complete the sealing of the periphery of the puncture opening 326. The vacuum is turned off and the front piece 321 and the rear piece 322 return to their original positions at the same time, and the exhaust is completed.

After the exhaust is completed, the transferring manipulator 5 takes out the battery cell 8 after the exhaust heat sealing is completed and moves the battery cell 8 to the clamp moving frame 21 in the first blanking process of the blanking device 4, then the clamp moving frame 21 of the blanking device 4 moves from the first blanking process 41 to the second blanking process 42, and at this time, the four-axis manipulator 6 grabs the battery cell 8 to the two-sealing edge trimmer 7 to perform two-sealing edge trimming machine operation.

Based on the above production and synthesis production line for the polymer pouch battery, fig. 14 shows a production method for the polymer pouch battery, which synchronously exhausts gas in the formation process, and comprises the following steps:

Fig. 15 shows that in step (iv), the opening formation includes the following substeps:

(8) standing and grading the capacity, and standing and grading the battery;

Compared with the prior art, in the production process of the battery, the formation process is synchronously exhausted, the equipment investment cost of separate treatment is reduced, the formation time is shortened, and the production efficiency is improved.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the described embodiments. It will be apparent to those skilled in the art that various changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention.

Claims

1. A production method of a polymer soft package battery is characterized in that air exhaust is synchronously performed in a formation process, and comprises the following steps:

2. The production method of the polymer soft package battery according to claim 1, wherein in the step (IV), the opening formation comprises the following substeps:

(8) standing and grading the capacity, and standing and grading the battery;

3. The production method of the polymer pouch battery according to claim 2, characterized in that in substep (6), the sealing operation is a hot-press sealing operation or a glue-spraying sealing operation.

4. The production method of the polymer soft package battery as claimed in claim 3, wherein the hot-press sealing operation is to clamp the cell airbag by two heat-seal frames, and a heating wire is arranged in each heat-seal frame to heat and seal the periphery of the piercing opening of the cell airbag by heating the heating wire and raising the heat-seal frames to a preset temperature.

5. The production method of the polymer soft package battery according to claim 3, wherein the glue spraying and sealing operation is to arrange a silica gel spray head in a cavity of a suction cup of the integrated device for opening formation and exhaust, and after the formation is completed, the spray head sprays special glue to seal the periphery of a puncture hole.