Brief analysis of the production process of lithium battery coating technology -Lithium - Ion Battery Equipment
The general process of coating: the coated substrate is released from the unwinding device and fed into the coating machine. After the end of the substrate is connected into a continuous belt by the splicing table, it is sent to the tension adjustment device and the automatic deviation correction device by the pulling device, and enters the coating device after adjusting the tension and position of the film path. The electrode sheet slurry is coated in sections according to the predetermined coating amount and blank length in the coating device.(Lithium - Ion Battery Equipment)
During double-sided coating, it automatically tracks the front side coating and blank length for coating. The coated wet pole piece is sent to the drying tunnel for drying, and the drying temperature is set according to the coating speed and coating thickness. The dried pole piece is rewound after tension adjustment and automatic deviation correction, for the next step of processing.
The pole piece slurry coating is relatively thick, the coating amount is large, and the drying load is large. At present, hot air impact drying technology is generally used. The positive electrode substrate is aluminum foil, which is chemically active and easily oxidized. In the manufacturing process of aluminum foil, a dense oxide film will be formed to prevent further oxidation of aluminum foil. Since the oxide film is thin, porous, soft and has good adsorption, but high temperature and high humidity can destroy this layer of oxide film. Speed up the oxidation reaction.
At present, the single-sided coating method is adopted. When the first side is coated, the other side is completely exposed to the hot air, and the hot air for drying the coating (oil system) should be at about 130°C, such as the moisture content in the hot air. If it is not effectively controlled, the oxidation of the aluminum foil will be intensified, which will affect the adhesion between the positive electrode material and the aluminum foil, and even cause shedding in severe cases.
The choice of coating method and control parameters have an important impact on the performance of lithium-ion batteries, which is mainly reflected in the control of coating drying temperature: if the drying temperature is too low during coating, the pole pieces cannot be completely dried; if the temperature is too high, the It may be because the organic solvent inside the pole piece evaporates too fast, and the surface coating of the pole piece appears to be cracked and peeled off;
During double-sided coating, it automatically tracks the front side coating and blank length for coating. The coated wet pole piece is sent to the drying tunnel for drying, and the drying temperature is set according to the coating speed and coating thickness. The dried pole piece is rewound after tension adjustment and automatic deviation correction, for the next step of processing.
The pole piece slurry coating is relatively thick, the coating amount is large, and the drying load is large. At present, hot air impact drying technology is generally used. The positive electrode substrate is aluminum foil, which is chemically active and easily oxidized. In the manufacturing process of aluminum foil, a dense oxide film will be formed to prevent further oxidation of aluminum foil. Since the oxide film is thin, porous, soft and has good adsorption, but high temperature and high humidity can destroy this layer of oxide film. Speed up the oxidation reaction.
At present, the single-sided coating method is adopted. When the first side is coated, the other side is completely exposed to the hot air, and the hot air for drying the coating (oil system) should be at about 130°C, such as the moisture content in the hot air. If it is not effectively controlled, the oxidation of the aluminum foil will be intensified, which will affect the adhesion between the positive electrode material and the aluminum foil, and even cause shedding in severe cases.
The choice of coating method and control parameters have an important impact on the performance of lithium-ion batteries, which is mainly reflected in the control of coating drying temperature: if the drying temperature is too low during coating, the pole pieces cannot be completely dried; if the temperature is too high, the It may be because the organic solvent inside the pole piece evaporates too fast, and the surface coating of the pole piece appears to be cracked and peeled off;
