Lithium tetrachloroaluminate

Lithium tetrachloroaluminate (LAC, lithium aluminium chloride) is an inorganic compound, a tetrachloroaluminate of lithium, with the formula LiAlCl4.
Solution of lithium tetrachloroaluminate in thionyl chloride is the liquid cathode and electrolyte of some lithium batteries, e.g. the lithium-thionyl chloride cell. Another cathode-electrolyte formulation is lithium tetrachloroaluminate+thionyl chloride+sulfur dioxide+bromine.

Other salts used in lithium battery electrolytes are lithium bromide, lithium perchlorate, lithium tetrafluoroborate, and lithium hexafluorophosphate; less common ones are lithium chloride, lithium iodide, lithium chlorate, lithium nitrate, lithium hexafluoroarsenate, lithium hexafluorosilicate, lithium bis(trifluoromethanesulfonyl)imide, and lithium trifluoromethanesulfonate.
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