Separators with layered double hydroxides for electrochemical cells

Abstract

Separators, electrochemical cells and methods are provided, to improve operation of cells such as metal-ion batteries and fuel cells. Separators comprise a porous, ionically conductive film including layered double hydroxide(s) (LDHs), which are functional ceramic additives, removing potentially harmful anions from the electrolyte by incorporating them into the LDH structure of positively-charged sheets with intermediary anions. For example, anions which are electrolyte decomposition products or cathode dissolution products may be absorbed into the LDH to prevent them from causing damage to the cell and shortening the cell's life. LDHs may be incorporated in the separator structure, coated thereupon or otherwise associated therewith. Additional benefits include dimensional stability during thermal excursions, fire retardancy and impurity scavenging.