Dry-method lithium battery pole piece forming mechanism and equipment

Abstract

The utility model discloses a dry-method lithium battery pole piece forming mechanism and equipment, which are characterized in that a rolling driving part drives a calendering roller to rotate, a composite driving part drives a composite roller to rotate, and dry-method slurry is rolled by the calendering roller and the composite roller to form a pole piece. The calendering roller with the small roller diameter can fully roll and thin a membrane, the composite roller with the large roller diameter can ensure that a pole piece can be compounded and compacted, the pole piece can reach the corresponding thickness, the compactness of the pole piece can be ensured, and the roll forming effect of the pole piece is improved.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery electrode sheets, specifically to a dry-process lithium battery electrode sheet forming mechanism and equipment. Background Technology

[0002] In the dry-process manufacturing of lithium battery electrodes, roller pressing is used to roll the dry slurry into a film. Current technology uses multi-stage rollers with equal diameters, either employing all small-diameter rollers for film thinning or all large-diameter rollers for composite compaction; these two methods are incompatible. Large-diameter roller pressing produces a thicker film with less thinning, requiring multiple stages of rolling to reach the target thickness. The orientation of the binder during rolling causes anisotropy in the electrode sheets, affecting their performance. Small-diameter roller pressing results in greater stretching during the composite process, leading to film wrinkling and poor composite effect, significantly increasing the resistivity of the electrode sheets. A single machine cannot guarantee both the film thinning amount and the composite compaction effect, resulting in poor film rolling forming results. Utility Model Content

[0003] In order to overcome the shortcomings of the existing technology, this utility model provides a dry lithium battery electrode forming mechanism and equipment, which can solve the problem of poor film roll forming effect.

[0004] The technical solution adopted by this utility model to solve its technical problem is as follows: On the one hand, a dry lithium battery electrode forming mechanism is provided, including a rolling assembly and a composite assembly. The rolling assembly includes a rolling drive and at least two calendering rolls. The rolling drive is used to drive the calendering rolls to rotate. The composite assembly includes a composite drive and at least two composite rolls. The composite drive is used to drive the composite rolls to rotate. The diameter of the composite rolls is larger than the diameter of the calendering rolls, and the composite rolls are arranged side by side with the calendering rolls.

[0005] As a further improvement to the above technical solution, four calendering rolls are provided, and two composite rolls are provided.

[0006] As a further improvement to the above technical solution, the roll pressing drive includes four roll pressing drive motors, which are used to drive the four calendering rolls respectively; the composite drive includes two composite drive motors, which are used to drive the two composite rolls respectively.

[0007] As a further improvement to the above technical solution, couplings are connected between the rotating shaft of the roll pressing drive motor and the calendering roll, and between the rotating shaft of the composite drive motor and the composite roll.

[0008] As a further improvement to the above technical solution, the diameter of the calendering roll furthest from the composite roll is larger than the diameter of the other three calendering rolls, and the diameters of the other three calendering rolls are the same.

[0009] As a further improvement to the above technical solution, the closer to the composite roll, the greater the linear speed of the calendering roll; the linear speed of each composite roll is the same, and the linear speed of the composite roll is greater than the linear speed of the calendering roll.

[0010] As a further improvement to the above technical solution, an unwinding assembly is also included, the unwinding assembly including an unwinding roller located above the composite roller, the unwinding roller being used to convey foil between two composite rollers that are far from the calendering roller.

[0011] As a further improvement to the above technical solution, a winding assembly is also included, which is used to wind up the film or electrode sheet.

[0012] On the other hand, a dry-process lithium battery electrode forming apparatus is provided, including a feeder and the aforementioned dry-process lithium battery electrode forming mechanism.

[0013] As a further improvement to the above technical solution, the dry lithium battery electrode forming mechanism also includes a support, the calendering roll and the composite roll are rotatably connected to the support, the support is provided with a guide trough, the guide trough is located above the calendering roll away from the composite roll, and the feeder is used to convey dry slurry to the guide trough.

[0014] The beneficial effects of this utility model are as follows: the calendering roller is driven to rotate by the roller pressing drive component, and the composite roller is driven to rotate by the composite drive component. The dry slurry is formed into an electrode sheet after being double-rolled by the calendering roller and the composite roller. Since the diameter of the composite roller is larger than that of the calendering roller, the calendering roller with a smaller diameter can fully roll-press and thin the film, while the composite roller with a larger diameter can ensure that the electrode sheet can be composite and compacted. The electrode sheet can achieve the corresponding thinness and ensure its density, thereby improving the roller pressing and forming effect of the electrode sheet. Attached Figure Description

[0015] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0016] Figure 1 This is a schematic diagram of the structure of the dry lithium battery electrode forming equipment provided in a preferred embodiment of the present invention;

[0017] Figure 2 This is a top view from another angle of the dry lithium battery electrode forming equipment provided in a preferred embodiment of this utility model;

[0018] Figure 3 This is a cross-sectional view of the dry lithium battery electrode forming equipment provided in a preferred embodiment of the present invention;

[0019] Figure 4 This is a cross-sectional view of the calendering roll and composite roll in operation according to a preferred embodiment of the present invention.

[0020] Reference numerals: 1. Roller assembly, 2. Composite assembly, 3. Unwinding assembly, 5. Diaphragm, 6. Foil, 7. Electrode, 8. Feeder, 9. Support;

[0021] 11. Roller drive component; 12. Calendering roll; 21. Composite drive component; 22. Composite roll; 31. Unwinding roll; 91. Guide chute.

[0022] 111. Roller drive motor; 121. First calendering roll; 122. Second calendering roll; 123. Third calendering roll; 124. Fourth calendering roll; 211. Composite drive motor; 212. Coupling. Detailed Implementation

[0023] The following will clearly and completely describe the concept, specific structure, and technical effects of this utility model in conjunction with embodiments and accompanying drawings, so as to fully understand the purpose, features, and effects of this utility model. Obviously, the described embodiments are only a part of the embodiments of this utility model, not all of them. Other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are all within the scope of protection of this utility model. Furthermore, all connections / connections involved in the patent do not simply refer to direct contact between components, but rather to the ability to form a better connection structure by adding or reducing connecting accessories according to specific implementation conditions. For example, fixed connections / fixed installations can use screw connections, bolt connections, pin connections, key connections, adhesive connections, mortise and tenon connections, welding, riveting, etc., as needed. For detachable connections, screw connections, bolt connections, threaded connections, snap-fit ​​connections, mortise and tenon connections, Velcro connections, etc., can be used as needed. The various technical features in this utility model can be combined interactively without contradicting each other.

[0024] Please see Figure 1-4 This utility model provides a dry-process lithium battery electrode forming mechanism, including a roll forming assembly 1, a composite assembly 2, an unwinding assembly 3, and a winding assembly (not shown in the figure). The roll forming assembly 1 is used to roll and thin the film 5, and the composite assembly 2 is used to compact the film 5 or to composite the film 5 with foil 6. The unwinding assembly 3 is used to transport the foil 6, and the winding assembly is used to wind up the film 5 or the electrode 7.

[0025] Specifically, the roll forming assembly 1 includes a roll forming drive 11 and four calendering rolls 12. The roll forming drive 11 drives the calendering rolls 12 to rotate. The composite assembly 2 includes a composite drive 21 and two composite rolls 22. The composite drive 21 drives the composite rolls 22 to rotate. The diameter of the composite rolls 22 is larger than the diameter of the calendering rolls 12, and the composite rolls 22 and calendering rolls 12 are arranged side by side. The four calendering rolls 12 are designated as a first calendering roll 121, a second calendering roll 122, a third calendering roll 123, and a fourth calendering roll 124. Please refer to [link to relevant documentation]. Figure 4 The dry slurry is fed between the first calendering roll 121 and the second calendering roll 122 for the first rolling. Then, the formed film 5 is fed between the second calendering roll 122 and the third calendering roll 123 for the second rolling. Then, the film 5 is fed between the third calendering roll 123 and the fourth calendering roll 124 for the third rolling, thus obtaining a sufficiently thinned film 5. Finally, the film 5 is fed between two large-diameter composite rolls 22 for rolling, resulting in a film 5 with good compaction. The successive rolling of the small-diameter calendering roll 12 and the large-diameter composite roll 22 improves the rolling forming effect of the film.

[0026] In other embodiments, two or three calendering rolls can be used to reduce the number of calendering rolls and save costs. Alternatively, four or more calendering rolls can be used to further improve the film thinning effect.

[0027] Please see Figure 2 The roll pressing drive unit 11 includes four roll pressing drive motors 111, which are used to drive four calendering rolls 12 respectively; the composite drive unit 21 includes two composite drive motors 211, which are used to drive two composite rolls 22 respectively. Each calendering roll 12 and composite roll 22 is driven by a different power source, so that the rotational speed of each calendering roll 12 and composite roll 22 can be controlled independently, and their rotational speeds can be the same or different.

[0028] Furthermore, couplings 212 are connected between the shaft of the roll drive motor 111 and the calender roll 12, and between the shaft of the composite drive motor 211 and the composite roll 22. The couplings 212 are used to transmit the power of the shaft of the roll drive motor 111 to the calender roll 12 and the power of the shaft of the composite drive motor 211 to the composite roll 22, thereby driving the calender roll 12 and the composite roll 22.

[0029] Please see Figure 3The diameter of the calendering roll 12 furthest from the composite roll 22 is larger than that of the other three calendering rolls 12, while the other three calendering rolls 12 have the same diameter. That is, the diameter of the first calendering roll 121 is larger than that of the other three calendering rolls 12, while the other three calendering rolls 12 have the same diameter. The side closer to the first calendering roll 121 is used for conveying raw materials. Setting it to have a larger diameter is beneficial for large pieces of material to be bitten in, and reduces the upward rebound of the material.

[0030] The closer to the composite roll 22, the greater the linear speed of the calender roll 12; all composite rolls 22 have the same linear speed, and the linear speed of the composite roll 22 is greater than that of the calender roll 12. The greater the linear speed, the faster the rolling process, which is beneficial for accelerating the production process.

[0031] Specifically, the unwinding assembly 3 includes an unwinding roller 31, which is located above the composite roller 22. The unwinding roller 31 is used to convey the foil 6 between the two composite rollers 22, which are away from the calendering roller 12. After the film 5 is rolled by the four calendering rollers 12, it is conveyed between the two composite rollers 22. At the same time, the unwinding roller 31 conveys the foil 6 between the two composite rollers 22, and the two composite rollers 22 combine the film 5 and the foil 6 into an electrode sheet 7.

[0032] After the four films 5 are rolled by the four calendering rollers 12, they can be further compacted by the two composite rollers 22, and then the film 5 is wound up by the winding assembly. Alternatively, please refer to Figure 4 The diaphragm 5 and foil 6 are simultaneously fed between two composite rollers 22 for composite bonding. After the two are bonded together, an electrode 7 is obtained, which is then wound up by a winding assembly.

[0033] A preferred embodiment of this utility model also provides a dry lithium battery electrode forming equipment, including a feeder 8 and the dry lithium battery electrode forming mechanism described in the above embodiment. The feeder 8 is used to convey dry slurry between the first calendering roll 121 and the second calendering roll 122 to achieve automated feeding and reduce labor costs.

[0034] Specifically, the dry-process lithium battery electrode forming mechanism also includes a support 9, and the calendering roll 12 and the composite roll 22 are rotatably connected to the support 9. The support 9 is provided with a guide trough 91, which is located above the calendering roll 12 away from the composite roll 22. The feeder 8 is used to convey dry slurry to the guide trough 91. The guide trough 91 is located above the first calendering roll 121. The guide trough 91 can control the flow direction of the dry slurry, ensuring that the dry slurry flows accurately between the first calendering roll 121 and the second calendering roll 122. In addition, the guide trough 91 can prevent the dry slurry from splashing and reduce raw material loss.

[0035] The above is a detailed description of the preferred embodiments of the present utility model. However, the present utility model is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present utility model. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A dry-process lithium battery electrode forming mechanism, characterized in that: The device includes a roll forming assembly and a composite assembly. The roll forming assembly includes a roll forming drive and at least two calendering rolls. The roll forming drive is used to drive the calendering rolls to rotate. The composite assembly includes a composite drive and at least two composite rolls. The composite drive is used to drive the composite rolls to rotate. The diameter of the composite rolls is larger than the diameter of the calendering rolls, and the composite rolls are arranged side by side with the calendering rolls.

2. The dry-process lithium battery electrode forming mechanism according to claim 1, characterized in that: The calendering rolls are provided with four, and the composite rolls are provided with two.

3. The dry-process lithium battery electrode forming mechanism according to claim 2, characterized in that: The roll pressing drive includes four roll pressing drive motors, which are used to drive the four calendering rolls respectively; the composite drive includes two composite drive motors, which are used to drive the two composite rolls respectively.

4. The dry-process lithium battery electrode forming mechanism according to claim 3, characterized in that: Couplings are connected between the shaft of the roll pressing drive motor and the calendering roll, and between the shaft of the composite drive motor and the composite roll.

5. The dry-process lithium battery electrode forming mechanism according to claim 2, characterized in that: The diameter of the calendering roll furthest from the composite roll is larger than the diameter of the other three calendering rolls, which have the same diameter.

6. The dry-process lithium battery electrode forming mechanism according to claim 1, characterized in that: The closer to the composite roll, the greater the linear velocity of the calendering roll; all composite rolls have the same linear velocity, and the linear velocity of the composite roll is greater than that of the calendering roll.

7. The dry-process lithium battery electrode forming mechanism according to claim 1, characterized in that: It also includes an unwinding assembly, which includes an unwinding roller located above the composite roller and is used to feed foil between two composite rollers that are away from the calendering roller.

8. The dry-process lithium battery electrode forming mechanism according to claim 1, characterized in that: It also includes a winding assembly for winding up the film or electrode.

9. A dry-process lithium battery electrode forming equipment, characterized in that: It includes a feeder and a dry lithium battery electrode forming mechanism as described in any one of claims 1-8.

10. The dry-process lithium battery electrode forming equipment according to claim 9, characterized in that: The dry lithium battery electrode forming mechanism also includes a support frame. The calendering roll and the composite roll are rotatably connected to the support frame. The support frame is provided with a guide trough, which is located above the calendering roll away from the composite roll. The feeder is used to convey dry slurry to the guide trough.

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