Separators with layered double hydroxides for electrochemical cells

A separator for a lithium-ion battery, comprising a porous, ionically conductive film including at least one layered double hydroxide (LDH) that is exposed to an electrolyte of the lithium-ion battery, and absorbs fluorine anions present in the electrolyte to increase the battery's tolerance to contaminants and to extend the battery's operational lifetime, and wherein the LDH comprises Mg6Al2(OH)18·4H2O (Meixnerite) and/or Mg6Al2(OH)16(CO3)·4H2O (Hydrotalcite), wherein the LDH further comprises at least one of:

• at least one compound having a formula [M2+1−x N3+x(OH−)2]x+[(Xn−)x/n·yH2O]x−, wherein M2+is a divalent cation, and N3+is a trivalent cation;
• Xn−is an anion;
• 0≤x≤1, 0≤y and n is an integer,
• embedded Ti4+,
• at least one compound having a formula (M2+aN3+b(OH−)2a+3b)·yH2O and/or (M2+aN3+b(OH−)2a+3b−cn) (Xn−)c·yH2O with a, b, c and n being integers, wherein M2+is a divalent cation, N3+is a trivalent cation, Xn−an intercalating n-valent anion and 0≤y, and/or
• at least one compound having a formula:
• [M1+1−xN3+x(OH−)2](2x-1)+[(Xn−)(2x-1)/n·yH2O](2x−1)−, wherein M+is a monovalent cation, and N3+is a trivalent cation;
• Xn−is an anion;
• 0≤x≤1, 0≤y and n is an integer.