Abstract: Carbonaceous insertion compounds and methods for preparation are described wherein the compounds comprise a highly disordered, impurity free, hard pre-graphitic carbonaceous host. Carbonaceous insertion compounds can be prepared which have large reversible capacity for lithium yet low irreversible capacity and voltage hysteresis. Such insertion compounds can be prepared by simple pyrolysis of suitable epoxy, phenolic resin, or carbohydrate precursors at an appropriate temperature. These insertion compounds may be suitable for use as high capacity anodes in lithium ion batteries.

Abstract: Carbonaceous insertion compounds and methods for preparation are described wherein the compounds comprise a highly disordered, impurity free, hard pre-graphitic carbonaceous host. Carbonaceous insertion compounds can be prepared which have large reversible capacity for lithium yet low irreversible capacity and voltage hysteresis. Such insertion compounds can be prepared by simple pyrolysis of suitable epoxy, phenolic resin, or carbohydrate precursors at an appropriate temperature. These insertion compounds may be suitable for use as high capacity anodes in lithium ion batteries.

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: Non-aqueous rechargeable lithium batteries can be equipped with internal electrical disconnect devices to protect against overcharge abuse. At the abnormally high voltages of overcharge, the devices can be activated by gasses generated as a result of the electrochemical polymerization of suitable monomer additives incorporated in the electrolyte. Aromatic compounds such as biphenyl are particularly suitable aromatic additives for LiCoO.sub.2 based lithium ion batteries.

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: The loss in delivered capacity as a function of the number of charge/discharge cycles in non-aqueous rechargeable lithium batteries can be reduced by exposing the electrolyte therein to P.sub.2 O.sub.5. The exposure to P.sub.2 O.sub.5 can be accomplished by incorporating P.sub.2 O.sub.5 in either electrode or other locations that contact the electrolyte. Alternately, the electrolyte can be exposed prior to assembling the battery. The invention is particularly suited to certain lithium ion rechargeable battery electrochemistries.

Abstract: Non-aqueous rechargeable lithium batteries are often equipped with internal electrical disconnect devices to protect against overcharge abuse. At the abnormally high voltages of overcharge, these devices can be activated by gasses generated as a result of the electrochemical polymerization of suitable monomer additives incorporated in the electrolyte. Aromatic compounds such as biphenyl are particularly suitable aromatic additives for LiCoO.sub.2 based lithium ion batteries.

Abstract: A battery construction is disclosed having improved safety behaviour under conditions of mechanical abuse, in particular crush type abuse, wherein an additional site for internal short circuiting is engineered therein. In certain circumstances, it can be beneficial to initiate the engineered short before other internal shorts occur. Additionally, it may be beneficial for the engineered short to have a lower resistance than the internal resistance of the battery. The invention is particularly suited for application in lithium ion type batteries.

Abstract: Spinel insertion compounds Li.sub.1+x Mn.sub.2-x-y M.sub.y O.sub.4 wherein M is a transition metal, 0<x< about 0.33, 0.ltoreq.y<about 1, can have relatively low surface area at relatively large values of x when prepared with a novel two step heating method. Li.sub.1 Mn.sub.2-y M.sub.y O.sub.4 is first prepared between a critical temperature, T.sub.c, and about 900.degree. C. Then, a lithium salt is mixed therewith and reacted at a temperature between about 400.degree. C. and T.sub.c. These compounds are suitable for use as a cathode in a lithium battery. The use of LiCl as the lithium salt can provide improved cycle life results in such a battery.

Abstract: The viscosity of certain non-aqueous electrolytes comprising a first lithium salt which can gel on the addition of P.sub.2 O.sub.5 can be reduced substantially by incorporating therein a small amount of a suitable viscosity reducing salt. In particular, the viscosity of a LiPF.sub.6 salt based electrolyte can be reduced by orders of magnitude by incorporating a small amount of LiBF.sub.4 therein. Such electrolytes are suitable for use in lithium ion batteries.

Abstract: Lithiated nickel dioxide cathode-active materials for electrochemical cells aving the formula Li.sub.x Ni.sub.2-x-y M.sub.y O.sub.2, with x being between about 0.8 and about 1.0, M being one or more metals selected from cobalt, iron, chromium, titanium, manganese and vanadium, and y being less than about 0.2, with the proviso that y is less than about 0.5 for cobalt, which material is substantially free of lithium hydroxide and lithium carbonate. The materials are prepared by providing a substantially homogeneous dry intermediate mixture of a starting material containing a nickel compound selected from nickel oxide, nickel hydroxide, and mixtures thereof, and optionally including one or more oxides or hydroxides of a transition metal selected from cobalt, iron, chromium, titanium, manganese and vanadium, together with between about a 10 and about a 25% stoichiometric excess of lithium hydroxide. The mixture is heat treated at a temperature above about 600.degree. C.

Abstract: Hydrides of lithiated nickel dioxide are disclosed, prepared by providing a substantially homogeneous dry intermediate mixture of a starting material containing a nickel compound selected from nickel oxide, nickel hydroxide and mixtures thereof, and optionally including one or more oxides or hydroxides of a transition metal selected from cobalt, iron, chromium, titanium, manganese and vanadium, together with about a 25% stoichiometric excess of lithium hydroxide. The mixture is heat-treated at a temperature above about 600.degree. C. in an atmosphere having a partial pressure of water vapor greater than about two torr. Electrochemical cells are also disclosed, incorporating the disclosed hydrides as a cathode-active material.