Valence Technology, Inc.

Other

Tracy E Kelley

Jeremy Barker

Porter H Mitchell

Chariclea A Scordilis-Kelley

M Yazid Saidi

Feng Gao

Robert J Horning

Lev M Dawson

Oliver J Gross

Hang Shi

Electrode active materials comprising two or more groups of particles having differing chemical compositions, wherein each group of particles comprises a material selected from:

Electrodes comprising mixed active particles

Electrode active materials comprising two or more groups of particles having differing chemical compositions, wherein each group of particles comprises a material selected from: (a) materials of the formula AM(XY)Z; and (b) materials of the formula AMO; and wherein (i) A, A, and Aare Li, Na, or K; (ii) Mand Mcomprise a transition metal; (iv) XYa phosphate or similar moiety; and (v) Z is OH, or halogen. In a preferred embodiment, AMOis AMnOhaving an inner and an outer region, wherein the inner region comprises a cubic spinel manganese oxide, and the outer region comprises a manganese oxide enriched in Mnrelative to the inner region. In a preferred embodiment, the compositions also comprise a basic compound.

The invention provides an electrochemically active material comprising particles of spinel lithium manganese oxide having on the surface of each particle cationic metal species bound to the spinel at anionic sites of the particle surface; where the cationic metal species includes a metal selected from the group consisting of transition metals, non-transition metals having a &plus;3 valence state, and mixtures thereof. The active material is characterized by a reduced surface area and increased capacity expressed in milliamp hour per gram as compared to the spinel alone.

Lithium manganese oxide-based active material

A method for activating electrochemical cells including the steps of sealing the electrochemical cells in a container with an activating electrolyte solvent and salt, treatment steps, such as the application of compression and decompression cycles to the container, for providing good distribution of the electrolyte within the electrochemical cells.

Method for distributing electrolyte in batteries

The invention provides an electrochemical cell having an electrolyte which comprises a solute, a solvent, and an additive. The additive is a dialkylamide. The dialkylamide lessens the extent of decomposition of the solute, which is a lithium salt. The ionic species of the lithium salt are thereby preserved. The additive also prevents damage to active material by absorbing excess charge energy below the breakdown potential of the active material.

Electrolytes having improved stability comprising an N,N-dialkylamide additive

The methods and compositions of the invention provide two solutions to reduce the reactivity of VDF-based copolymers to lithiated graphite. The two approaches can be used separately or combined. In one embodiment, the relative proportion of the VdF and the other fluorinated monomer (OFM, i.e. HFP) in the copolymer is significantly reduced below conventional formulations in order to reduce the reactivity of the copolymer. In a second approach, the reactivity of the copolymer, over a broad range of monomer VdF:OFM molar ratios, is reduced by deactivating the reactive sites on the copolymer, thereby blocking the ability to undergo undesired reaction during cell operation. These methods and compositions have heretofore not been proposed and are of primary importance in preventing large exothermic reaction which can lead to thermal runaway when conventional polymer formulations are utilized in batteries in the presence of reactive components such as lithiated graphite.

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Henderson, NV, United States of America

Tracy E Kelley