Abstract: The cycling stability and capacity of Li-ion rechargeable batteries are improved, particularly in an elevated temperature range of about 55.degree. C., by the use of lithium magnesium manganese oxy-fluoride electrode components having the general formula, Li.sub.1+x Mg.sub.y Mn.sub.2-x-y O.sub.4-z F.sub.z, where x.ltoreq.0.2, 0.1.ltoreq.y.ltoreq.0.3, and 0.01.ltoreq.z.ltoreq.0.5.

Abstract: The cycling stability and capacity of Li-ion rechargeable batteries are improved, particularly in an elevated temperature range of about 55.degree. C., by the use of lithium aluminum manganese oxy-fluoride electrode components having the general formula, Li.sub.1+x Al.sub.y Mn.sub.2-x-y O.sub.4-z F.sub.z, where x.ltoreq.0.4, 0.1.ltoreq.y.ltoreq.0.3, and 0.05.ltoreq.z.ltoreq.0.5.

Abstract: A rechargeable lithiated intercalation battery cell having reduced self-discharge comprises a negative electrode, a nonaqueous electrolyte, and a positive electrode wherein the surfaces of the aggregate lithiated intercalation composition particulates comprising the positive cell electrode have been coated with a passivating layer of a composition comprising a borate, lithiated borate, aluminate, lithiated aluminate, silicate, lithiated silicate, or mixtures thereof.

Abstract: The extent of self-discharge of rechargeable Li-ion secondary batteries is significantly reduced by treatment of LiMn.sub.2 O.sub.4 intercalation compound electrode material with a chelating agent, such as acetylacetone. This treatment decreases the incidence of non-coordinated Mn-ion sites which can lead to battery electrolyte decomposition and resulting loss of battery capacity. The treatment, which also includes annealing at about 400.degree. C. to 800.degree. C., further prevents such decomposition by varying the surface area and topography of the potentially catalytic electrode material.

Abstract: Li.sub.x CoO.sub.2 wherein x is about 1.00 to 1.15 is annealed at about 950.degree. C. to 1000.degree. C. for about 0.25 to 10 hours to yield a lithium intercalation material which is used in an electrode to provide a rechargeable battery having high specific capacity and the capability of maintaining such capacity over numerous operating charge/discharge cycles.

Abstract: The cycling stability and capacity of li-ion rechargeable batteries are improved by the use of lithium manganese oxy-fluoride electrode component intercalation materials having the general formula, Li.sub.1+x M.sub.y Mn.sub.2-x-y O.sub.4-z F.sub.z, where M is a transition metal, e.g., Co, Cr, or Fe, and x.ltoreq.0.4, y.ltoreq.0.3, and 0.05.ltoreq.z.ltoreq.1.0.

Abstract: An apparatus and method for monitoring structural changes of an electrode in a rechargeable battery include an in situ x-ray study electrochemical cell holder (30) comprising top and bottom cell holder members (32, 34) including at least one beryllium window element (36) for transmission of diffractometer x-radiation. A rechargeable battery cell (43) mounted within the x-ray cell holder enclosure comprises an electrolyte/separator element (68) interposed between positive and negative electrodes (64, 66). A current collector element (70) formed of an electrically-conductive open-mesh grid is disposed between the positive electrode and the separator to enable ion-conducting contact of the electrode and separator while maintaining electrical continuity between the electrode and an external x-ray cell holder terminal (54).

Abstract: A method of making a single phase, layered lithiated transition metal oxide material which comprises reacting a transition metal hydroxide with a lithium source in a basic solution in the presence of water at a pressure greater than atmospheric and at a temperature of from about 50.degree. C. to 150.degree. C.

Abstract: LiCoO.sub.2 and LiNiO.sub.2 are fully delithiated electrochemically using solid state electrolytic cells and oxidation resistant electrolytes to yield new phases of CoO.sub.2 and NiO.sub.2.