Polymer Solution Preparation: The first step in the wet process involves preparing a polymer solution. The selected polymer, such as polyethylene (PE) or polypropylene (PP), is dissolved in a suitable solvent to create a homogeneous solution. This solution will serve as the precursor for the separator material.

Coating or Casting: The polymer solution is then coated or cast onto a moving substrate, such as a conveyor belt or rotating drum. The coating thickness is carefully controlled to achieve the desired separator thickness.

Solvent Removal: After the coating process, the separator goes through a drying stage to remove the solvent from the polymer. This can be done through various methods, such as evaporation or hot air drying. The drying process ensures the solidification of the polymer and the formation of a porous structure.

Calendering: In some cases, the separator may undergo a calendering process. Calendering involves passing the separator material through rollers to enhance its thickness uniformity and smoothness further. This step helps improve the mechanical strength and overall quality of the separator.

Pore Formation: The separator may undergo a pore formation process to create the necessary porous structure. This can be achieved through stretching, heat treatment, or controlled mechanical deformation. The pore formation step is crucial for optimizing the separator’s electrolyte management and ion transport properties.

Finishing and Quality Control: The manufactured separators undergo various finishing processes, such as trimming the edges and ensuring uniformity in thickness and pore size distribution.