Method for manufacturing an assembly comprising a separator and porous electrode, an assembly comprising a separator and porous electrode, and electrochemical device containing such an assembly

A method for manufacturing an electrochemical device having an assembly that includes a porous electrode and a porous separator, the porous electrode having a porous layer free of binder, a porosity of between 25% and 50% by volume, and pores having an average diameter of less than 50 nm, the porous separator including a porous inorganic layer free of binder deposited on the porous electrode, the porous inorganic layer having a porosity of between 25% and 50% by volume and pores having an average diameter of less than 50 nm, the manufacturing method comprising:

• (a) providing a substrate, a first colloidal suspension or a paste comprising aggregates or agglomerates of monodisperse primary nanoparticles of at least one active electrode material, having an average primary diameter of between 2 nm and 60 nm, said aggregates or agglomerates having an average diameter of between 100 nm and 200 nm, and a second colloidal suspension comprising aggregates or agglomerates of nanoparticles of at least one inorganic material, having an average primary diameter of between 2 nm and 60 nm, said aggregates or agglomerates having an average diameter of between 100 nm and 200 nm, wherein the substrate is a substrate acting as an electric current collector or an intermediate substrate,
• (b) depositing a layer from said first colloidal suspension or said paste on at least one face of said substrate using one of:
• electrophoresis, ink-jet printing, flexographic printing, doctor blade coating, roll coating, curtain coating, dip-coating, and extrusion slot-die coating;
• (c) drying said deposited layer before or after separating said deposited layer from the intermediate substrate, then, heat treating the dried layer under an oxidising atmosphere, then consolidating the heat treated layer by pressing and/or heating to obtain a mesoporous, inorganic layer;
• (d) depositing a coating of an electronically conductive material on and inside the pores of said mesoporous, inorganic layer to form said porous electrode;
• (e) depositing a porous inorganic layer from the second colloidal suspension on said porous electrode by one of:
• electrophoresis, ink-jet printing, flexographic printing, roll coating, curtain coating, doctor blade coating, extrusion slot-die coating, and dip-coating,
• (f) drying the deposited porous inorganic layer under an air flow, and then heat treating the dried porous inorganic layer at a temperature below 400° C. to obtain said assembly.