Organic lithium salt electrolytes having enhanced safety for rechargeable batteries and methods of making the same

摘要

Organic lithium salts suitable for use in electrolytes for primary or secondary rechargeable batteries include de-localized bulky anions over Lewis acid fragments, typically BF₃, and organic moieties. The organic moieties may be, for example, anions derived from fused nitrogen heterocycles (e.g. benzeneimidate, benzitriazolate and the like); multi carboxylates (e.g. oxalate, 1,2,4,5-benzenetetracarboxylate and the like), and pyromellitic diimidate. The organic lithium salts of the invention have the general formula: Li_q[Org(MX_n)_m], in which Org represents the organic moieties and MX_n represents an organic or inorganic boron, aluminum or phosphorous containing Lewis acid. The organic lithium salts are conveniently prepared by reacting an organic compound having at least one de-protonation group selected from NH, OH, SH or COOH with an inorganic or organic lithium compound to generate an organic lithium processor salt, and thereafter bringing the organic lithium processor salt into contact with an inorganic or organic Lewis acid to obtain the organic lithium product salt.