Abstract: The loss in delivered capacity (fade rate) after cycling non-aqueous rechargeable lithium batteries can be reduced by incorporating a small amount of an improved additive in the battery. Improved additives include boron trifluoride (BF.sub.3), fluoboric acid (HBF.sub.4), or complexes thereof. The invention is particularly suited to lithium ion batteries. Complexes comprising BF.sub.3 and dietyl carbonate or ethyl methyl carbonate can be prepared which are particularly effective additives. Preferably, the additive is dissolved in the electrolyte.

Abstract: The loss in delivered capacity upon cycling non-aqueous rechargeable lithium batteries can be reduced by incorporating a small amount of B.sub.2 O.sub.3 additive in the electrolyte. The B.sub.2 O.sub.3 additive is preferably dissolved in the electrolyte prior to assembling the battery. The invention is particularly suited to lithium ion rechargeable batteries.

Abstract: Lithiated manganese oxides are synthesized using a novel two stage process. Using appropriate starting materials, lithiation is accomplished via low temperature ion exchange in aqueous warm salt solution. A drying stage follows which completes the synthesis. Materials suitable for use as cathodes in lithium ion rechargeable batteries have been prepared in this way. Other solid solution transition metal materials might also be prepared using a similar low temperature ion exchange process.

Abstract: Unitary fill port and terminal constructions and methods for filling and sealing are disclosed for electrical devices comprising liquids. The invention is particularly suited for use in prismatic batteries comprising non-aqueous organic electrolytes.

Abstract: The loss in delivered capacity (fade) after cycling non-aqueous rechargeable lithium batteries can be reduced by incorporating a small amount of certain additive compounds in the battery. The additive compound comprises boron, oxygen, and organic end groups that are chemically compatible with the battery components. The structure of the additive compound contains a boroxine (BO).sub.3 ring. The invention is particularly suited to lithium ion batteries. Trimethoxyboroxine and trimethylboroxin are particularly effective additives. Preferably, the additive compound is dissolved in the electrolyte.

Abstract: A novel form of the insertion compound having the formula Li.sub.x Mn.sub.2 O.sub.4 and a tetragonal crystal structure has been synthesized wherein x is a number in the range from about 1.7 to about 2.1. The insertion compound has a voltage relative to Li/Li.sup.+ in the range from about 3.2 to about 3.8 V and is thus air stable. The insertion compound is useful as an electrode material for lithium ion batteries. In particular, the insertion compound can be used as a cathode additive to result in a cathode limited construction. In certain applications, this can result in improved tolerance to overdischarge.