Etching device

A roll-to-roll etching device for etching a current collector, the current collector comprising a plastic film and a to-be-etched metal layer disposed on one surface of the plastic film, the etching device comprising:

• a porous roller, wherein the porous roller is a hollow structure with two end openings at both ends, an etching liquid is accommodated in the hollow structure, and an outer surface of the porous roller is provided with a plurality of openings;
• at least one pressing roller, attached to the porous roller and arranged above a liquid level of the etching liquid in the hollow structure, and used for pressing and attaching the metal layer onto the outer surface of the porous roller;
• a liquid collecting container, wherein at least part of the porous roller is arranged in the liquid collecting container;
• a liquid introducing apparatus connected to the liquid collecting tank used for introducing the etching liquid into the hollow structure through at least one end opening of the two end openings at both ends of the porous roller;
• a cleaning apparatus, arranged downstream in a conveying direction of the metal layer of the porous roller, wherein the cleaning apparatus comprises a washing tank, a transmission roller, and a cleaning liquid arranged in the washing tank, wherein the transmission roller is merged or submerged in the cleaning liquid and used to convey the metal layer into the washing tank, the cleaning liquid is used to clean off residual etching liquid on the metal layer,
• wherein during rotation of the porous roller, the etching liquid is continuously supplied into the hollow structure and passes under pressure from within the hollow structure through at least part of the openings of the plurality of openings to continuously soak the metal layer in contact with the at least part of the openings, so as to continuously etch the metal layer in contact with the at least part of the openings to form a plurality of openings on the surface of the metal layer, each opening of the plurality of openings on the porous roller correspond to each opening of the openings on the metal layer, and the liquid collecting apparatus is used for collecting the etching liquid leaked from the porous roller so as to avoid contamination by the etching liquid, the liquid introducing apparatus is connected to the liquid collecting tank and capable of transferring the etching liquid collected in the liquid collecting tank to the liquid introducing apparatus to recycle the etching liquid.