Abstract: An electrolyte for a rechargeable lithium battery is provided. The electrolyte includes a non-aqueous organic solvent and a lithium salt. The non aqueous organic solvent includes cyclic carbonate such as ethylene carbonate and propylene carbonate, chain carbonate such as dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate and methyl propyl carbonate, and alkyl acetate such as n-methyl acetate, n-ethyl acetate and n-propyl acetate. The electrolyte can be used in a rechargeable lithium battery to provide good low temperature characteristics and safety.

Abstract: A process for purification of lithium battery electrolyte solutions is provided whereby the concentrations of trace amounts of impurities such as water in the electrolyte solutions can be reduced. Such electrolyte solutions generally include at least one lithium salt solute contained in at least one organic solvent. Lithium and a second metal with which lithium is capable of intercalating are first placed in electrical contact with one another and then placed in the electrolyte solution. Preferably, aluminum is used as the second metal and the two metals are provided as separate layers that are pressed together in a rolling mill to form a bimetallic sheet. The solution containing the bimetallic sheet is agitated to encourage the reactions which reduce the levels of impurities such as water in the electrolyte solution. The resulting purified solution is then filtered to remove any remaining metal or reaction products.

Abstract: An improved current collector for use with lithium ion batteries includes an aluminum grid of the type used for making conventional current collectors that is plated with a layer of zinc, the outermost portion of which is oxidized to zinc oxide. The current collector is made by first cleaning an aluminum grid in an aqueous basic solution to remove its outer layer of alumina. The cleaned aluminum grid is then plated with zinc by contact with an aqueous solution of zinc oxide. The plated aluminum grid is rinsed and dried in air to oxidize the outer surface of the zinc and form an outer layer of zinc oxide. The resulting zinc-plated current collector can be made into a battery with a higher conductivity at the interface between the current collector and the electrode active materials than a battery made with a conventional aluminum current collector. It also has a rough outer surface which improves its adhesion to the polymeric layers used in constructing a plastic lithium ion battery.