Coating system

A coating system, applied to coating a substrate to form an electrode plate, comprising:

• a coating head, equipped with two dispensing cavities independent of each other, wherein each of the dispensing cavities comprises a coating opening;
• two feeding apparatuses connected to the dispensing cavities in a one-to-one correspondence to form two combinations composed of the dispensing cavities and the feeding apparatuses, each of the two combinations comprising a dispensing cavity and a feeding apparatus, and configured to feed a slurry to the dispensing cavities;
• a valve disposed between the dispensing cavity and the feeding apparatus in at least one of the two combinations composed of the dispensing cavities and the feeding apparatuses, and configured to implement communication or disconnection between the dispensing cavity and the feeding apparatus;
• the coating head comprises a lower die, a middle die, and an upper die;
• one of the dispensing cavities is formed between a lower surface of the upper die and an upper surface of the middle die, and another one of the dispensing cavities is formed between a lower surface of the middle die and an upper surface of the lower die, one of the dispensing cavities includes a first groove and a second groove spaced out in a first direction, a width of the first groove is greater than a width of the second groove, and the second groove is closer to the coating opening than the first groove, both the first groove and the second groove are arc grooves, the another one of the dispensing cavities includes a third groove and a fourth groove spaced out in the first direction, a width of the third groove is greater than a width of the fourth groove, and the fourth groove is closer to the coating opening than the third groove, both the third groove and the fourth groove are arc grooves;
• the coating head further comprises two spacers, and the two spacers are disposed between the upper die and the middle die, and between the middle die and the lower die, respectively;
• the coating opening is disposed at the spacer;
• each of the feeding apparatuses comprises a tank and a feeding pump, and the feeding pump is configured to pump the slurry in the tank to one of the dispensing cavities;
• the valve comprises a valve body, a first valve core, a second valve core, a first drive structure, and a second drive structure;
• the valve body comprises an in-feed port, a back-feed port, and an out-feed port, the out-feed port communicates with one of the dispensing cavities, the in-feed port communicates with an outlet of the feeding pump, and the back-feed port communicates with the tank;
• the first drive structure drives the first valve core to move in the valve body so as to implement communication or disconnection between the in-feed port and the out-feed port;
• the second drive structure drives the second valve core to move in the valve body so as to implement communication or disconnection between the out-feed port and the back-feed port;
• when coating is implemented, the first drive structure drives the first valve core to open, so that the in-feed port communicates with the out-feed port, the second drive structure drives the second valve core to close, so that the out-feed port is disconnected from the back-feed port;
• when no coating is required, the first drive structure drives the first valve core to close, so that the in-feed port is disconnected from the out-feed port, the second drive structure drives the second valve core to open, so that the out-feed port communicates with the back-feed port;
• wherein the one of the dispensing cavities further includes a flow channel connecting the first groove, the second groove, and the coating opening, and the width of the second groove is greater than a width of the flow channel, and the second groove is configured to reduce flow speed of the incoming slurry;
• the first groove having only an arc shape is disposed only inside one of the upper die or the lower die;
• and
• a surface of the upper die facing the middle die includes the first groove, a surface of the middle die facing the upper die includes the second groove, a surface of the middle die facing the lower die is flat, and a surface of the lower die facing the middle die includes both the third groove and the fourth groove.