IMPROVED MEMBRANES, CALANDRATED MICROPOROUS MEMBRANES, BATTERY SEPARATORS AND APPROPRIATE METHODS Russian patent published in 2021 - IPC H01M10/585 

FIELD: process engineering.

SUBSTANCE: invention relates to improved microporous single or multi-layer battery separating membranes and methods of their manufacture. Method for manufacturing a multilayer polyethylene/polypropylene/polyethylene microporous membrane includes stretching in the longitudinal direction followed by stretching in the transverse direction and the subsequent stage of calendering as a means of reducing the thickness of the multilayer microporous membrane to reduce the relative porosity of the membrane in a controlled manner and to increase the tensile strength in the transverse direction. Thus, a thin multi-layer microporous membrane is obtained, on which polymer-ceramic coatings are easily applied, which has excellent mechanical strength characteristics due to its inner polypropylene layer and thermal shutdown function due to its polyethylene layers.

EFFECT: mechanical strength, increased productivity.

15 cl, 42 dwg, 4 tbl