Preparation process of all-solid-state positive plate

Abstract

The invention relates to an all-solid-state positive plate preparation process which comprises the following steps: S1, positive electrode coating: uniformly coating a current collector with slurry prepared by mixing a positive electrode active material, a conductive agent, a binder and a solid electrolyte; s2, drying: removing a solvent in the slurry, and drying to form a positive electrode coating; s3, laser cleaning, wherein impurities, an oxide layer and residues on the surface of the positive electrode coating are removed through laser cleaning; s4, dispensing: dispensing on two sides of the head part and the tail part of the pole piece; s5, curing: heating to completely cure the dispensing material; s6, rolling, wherein the rubber frame is combined with the positive electrode coating through rolling; s7, die cutting: forming a positive plate through die cutting; the laser cleaning is carried out before rolling, the laser cleaning efficiency is higher than that after rolling, the cleaning effect is better, rolling is carried out after glue dispensing and vacancy filling, a glue dispensing layer can be better combined with the positive electrode coating, and the glue frame and the positive electrode coating are rolled at the same time, so that the glue frame and the positive electrode coating can be better tightly combined.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a process for preparing an all-solid-state positive electrode. Background Technology

[0002] With the increasing demand for high-energy-density and high-safety batteries from new energy vehicles and energy storage devices, solid-state batteries have become a research hotspot due to their superior stability and safety. During the production of all-solid-state batteries, in order to solve the solid-solid interface problem, they need to undergo isostatic pressure of 600MPa. This causes the overhang of the cell design to face problems such as localized fracture due to the high pressure, resulting in battery short circuits and low manufacturing yield.

[0003] Currently, in order to solve the above-mentioned problems in the production process of all-solid-state batteries, the industry has reached a consensus to apply adhesive or make adhesive frames at the overhang. However, at present, almost all of these processes are applied to the die-cut electrode sheets. The adhesive layer width has a large deviation, and the adhesive layer thickness is significantly different from the positive electrode coating, which not only results in low efficiency but also poor performance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a process for preparing an all-solid-state positive electrode.

[0005] This invention provides a process for preparing an all-solid-state positive electrode, comprising the following steps: Step S1, positive electrode coating: a slurry made by mixing positive electrode active material, conductive agent, binder and solid electrolyte is uniformly coated on the current collector. Step S2: Drying removes the solvent from the slurry and forms the positive electrode coating; Step S3, laser cleaning, laser cleaning removes impurities, oxide layer and residues from the surface of the positive electrode coating; Step S4, dispensing: Apply dispensing material to both sides of the head and tail of the electrode. Step S5, curing: Heat the material to fully cure it and form a glue frame. Step S6, rolling, rolling makes the frame bonded to the positive electrode coating; Step S7, die cutting, die cutting to form a positive electrode sheet.

[0006] Preferably, in step S1, the current collector is an aluminum foil current collector.

[0007] Preferably, in step S3, during laser cleaning, the cleaning area avoids the current collector.

[0008] Preferably, in step S3, the laser cleaning station is equipped with one.

[0009] Preferably, in step S4, the dispensing material is one of UV adhesive, hot melt adhesive, or ceramic coating.

[0010] Preferably, in step S6, the thickness of the roll-pressed frame is consistent with that of the positive electrode coating.

[0011] Compared with the prior art, the beneficial effects of the present invention are: After the positive electrode is coated and dried, it is then laser-cleaned and glued, and finally rolled and die-cut. By setting the rolling step after laser cleaning and glue dispensing, and performing laser cleaning before rolling, the efficiency of laser cleaning is higher than that after rolling, and the cleaning effect is better. Moreover, rolling after glue dispensing and filling gaps allows the glue layer to bond better with the positive electrode coating. Furthermore, rolling the frame and the positive electrode coating simultaneously ensures a tighter and more secure bond between them. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the all-solid-state positive electrode preparation process according to an embodiment of this application.

[0013] Figure 2 This is one of the schematic diagrams of the positive electrode structure in the embodiments of this application; Figure 3 This is the second schematic diagram of the positive electrode structure in an embodiment of this application.

[0014] Detailed implementation method.

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] like Figure 1-3 As shown: This embodiment describes a process for preparing an all-solid-state positive electrode, including the following steps: Step S1, positive electrode coating: a slurry made by mixing positive electrode active material, conductive agent, binder and solid electrolyte is uniformly coated on the upper and lower sides of the current collector, wherein the current collector is an aluminum foil current collector. Step S2: Drying removes the solvent from the slurry, the coating is cured, and drying forms the positive electrode coating; The drying process employs segmented control, with a drying temperature range of 80-170℃ and a drying time range of 15-35 minutes. By controlling the drying temperature and time, the solvent is ensured to evaporate completely. Step S3, laser cleaning: Laser cleaning removes impurities, oxide layer, residues, and burrs and residues from the surface of the positive electrode coating to avoid affecting subsequent processes. Step S4, dispensing: Dispensing adhesive material on both sides of the head and tail of the electrode sheet for subsequent bonding and fixing of the battery cell. The dispensing area formed by dispensing needs to be sealed and connected with the current collector and the positive electrode coating. Step S5, curing: Heat the material to fully cure it and form a glue frame. The curing temperature range is 70-130 degrees Celsius, and the curing temperature varies depending on the type of adhesive. Step S6, Rolling: Rolling allows the frame to bond and compact with the positive electrode coating, increasing the density of the active material and the flatness of the electrode sheet. During rolling, the frame and the positive electrode coating are rolled with the same force, and the frame and the positive electrode coating have the same thickness. Step S7, die cutting, die cutting to form a positive electrode sheet, the distance between two adjacent die-cut areas is 3-6mm; During die cutting, the size and shape of the electrode sheet can be adjusted according to requirements.

[0017] It should be noted that in step S1, the coating speed range during positive electrode coating is 12-80 m / min, the thickness range of the single-sided coating layer is 45-155 μm, and the thickness difference between the upper and lower coating layers is no more than 2.8% of the thickness of the single-sided coating layer.

[0018] It should be noted that in step S3, a laser cleaning station is provided, which reduces equipment costs. During laser cleaning, the cleaning area avoids the current collector to prevent ablation of the aluminum foil and the formation of metal beads.

[0019] It should be noted that the dispensing material is one of UV adhesive, hot melt adhesive, or ceramic coating. During dispensing, a sealing frame is formed. The temperature during dispensing will also change depending on the dispensing material, ensuring that the electrode does not deform while the dispensing cures.

[0020] It should be noted that by setting the roller pressing after laser cleaning and dispensing, the glue frame and the positive electrode coating are rolled simultaneously during the roller pressing process, which allows the glue frame and the positive electrode coating to be better and more tightly bonded, and to have a consistent thickness.

[0021] Before operation step S1, the necessary raw materials and processing equipment are set up. The raw materials include current collector, positive electrode coating material, and dispensing material. The positive electrode coating material is a slurry made by mixing positive electrode active material, conductive agent, binder, and solid electrolyte. The processing equipment includes a coating mechanism, a drying mechanism, a laser cleaning mechanism, a dispensing mechanism, a curing mechanism, a rolling mechanism, and a die-cutting mechanism. After the positive electrode is coated and dried, laser cleaning and dispensing are performed, and finally rolling and die-cutting are performed. By setting the rolling step after laser cleaning and dispensing, and performing laser cleaning before rolling, the efficiency of laser cleaning is higher than that after rolling, and the cleaning effect is better. Moreover, rolling after dispensing and filling gaps allows the dispensing layer to better bond with the positive electrode coating. Rolling the frame and the positive electrode coating at the same time allows the frame and the positive electrode coating to bond better and more tightly.

[0022] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0023] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A process for preparing an all-solid-state positive electrode, characterized in that, Includes the following steps: Step S1, positive electrode coating: a slurry made by mixing positive electrode active material, conductive agent, binder and solid electrolyte is uniformly coated on the current collector. Step S2: Drying removes the solvent from the slurry and forms the positive electrode coating; Step S3, laser cleaning, laser cleaning removes impurities, oxide layer and residues from the surface of the positive electrode coating; Step S4, dispensing: Apply dispensing material to both sides of the head and tail of the electrode. Step S5, curing: Heat the material to fully cure it and form a glue frame. Step S6, rolling, rolling makes the frame bonded to the positive electrode coating; Step S7, die cutting, die cutting to form a positive electrode sheet.

2. The all-solid-state cathode fabrication process according to claim 1, characterized in that: In step S1, the current collector is an aluminum foil current collector.

3. The all-solid-state cathode fabrication process according to claim 1, characterized in that: In step S3, during laser cleaning, the cleaning area avoids the current collector.

4. The all-solid-state cathode fabrication process according to claim 1, characterized in that: In step S3, a laser cleaning station is provided.

5. The all-solid-state cathode fabrication process according to claim 1, characterized in that: In step S4, the dispensing material is one of UV adhesive, hot melt adhesive, or ceramic coating.

6. The all-solid-state cathode fabrication process according to claim 1, characterized in that: In step S6, the thickness of the roll-pressed frame is consistent with that of the positive electrode coating.

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