Envia Systems, Inc.

Zenlabs Energy, Inc.

Ionblox, Inc.

Subramanian Venkatachalam

Herman Adrian Lopez

Sujeet Kumar

Charan Masarapu

Haixia Deng

Yogesh Kumar Anguchamy

Yongbong Han

Shabab Amiruddin

Bing Li

Deepak Kumaar Kandasamy Karthikeyan

Sanjeev Sharma

Charles A Bowling

Deepak Kumaar Karthikeyan

Deepak Kumaar K Karthikeyan

Xianyu Iris Li

Pedro A Hernandez-Gallegos

Pedro A Hernández Gallegos

Yingnan Dong

Yezi Bei

Kevin Hays

High capacity silicon based anode active materials are described for lithium ion batteries. These materials are shown to be effective in combination with high capacity lithium rich cathode active materials. Supplemental lithium is shown to improve the cycling performance and reduce irreversible capacity loss for at least certain silicon based active materials. In particular silicon based active materials can be formed in composites with electrically conductive coatings, such as pyrolytic carbon coatings or metal coatings, and composites can also be formed with other electrically conductive carbon components, such as carbon nanofibers and carbon nanoparticles. Additional alloys with silicon are explored.

Electrodes and lithium ion cells with high capacity anode materials

Polymer binders for negative electrodes with silicon based active materials are described based on poly(acrylamide-co-acrylate salts). Lithium ion batteries incorporating electrodes formed with the binders achieve longer cycling with suitable performance. Mechanical properties associated with each of the moieties of the copolymers are studied to guide polymer selection.

Lithium ion cells with silicon based active materials and negative electrodes with water-based binders having good adhesion and cohesion

A composite coated form of lithium cobalt oxide is described that can achieve improved cycling at higher voltages. Liquid phase and combined liquid and solid phase coating processes are described to effectively form the composite coated powders. The improved cycling positive electrode materials can be effectively combined with either graphitic carbon negative electrode active materials or silicon based high capacity negative electrode active materials. Improved battery designs can achieve very high volumetric energy densities in practical battery formats and with reasonable cycling properties.

Positive electrode active materials with composite coatings for high energy density secondary batteries and corresponding processes

Improved negative electrodes can comprise a silicon based active material blended with graphite to provide more stable cycling at high energy densities. In some embodiments, the negative electrodes comprise a blend of polyimide binder mixed with a more elastic polymer binder with a nanoscale carbon conductive additive. Electrolytes have been formulated that provide for extended cycling of cells incorporating a mixture of a silicon-oxide based active material with graphite active material in negative electrodes that can be matched with positive electrodes comprising nickel rich lithium nickel manganese cobalt oxides to cells with unprecedented cycling properties for large capacity cell based on a silicon negative electrode active material.

Lithium ion cells with high performance electrolyte and silicon oxide active materials achieving very long cycle life performance

Improved negative electrodes can comprise a silicon based active material blended with graphite to provide more stable cycling at high energy densities. In some embodiments, the negative electrodes comprise a blend of polyimide binder mixed with a more elastic polymer binder with a nanoscale carbon conductive additive. The silicon-based blended graphite negative electrodes can be matched with positive electrodes comprising nickel rich lithium nickel manganese cobalt oxides to form high energy density cells with good cycling properties.

Electrodes with silicon oxide active materials for lithium ion cells achieving high capacity, high energy density and long cycle life performance

Improved high energy capacity designs for lithium ion batteries are described that take advantage of the properties of high specific capacity anode active compositions and high specific capacity cathode active compositions. In particular, specific electrode designs provide for achieving very high energy densities. Furthermore, the complex behavior of the active materials is used advantageously in a radical electrode balancing design that significantly reduced wasted electrode capacity in either electrode when cycling under realistic conditions of moderate to high discharge rates and/or over a reduced depth of discharge.

Battery cell engineering and design to reach high energy

Supplemental lithium can be used to stabilize lithium ion batteries with lithium rich metal oxides as the positive electrode active material. Dramatic improvements in the specific capacity at long cycling have been obtained. The supplemental lithium can be provided with the negative electrode, or alternatively as a sacrificial material that is subsequently driven into the negative electrode active material. The supplemental lithium can be provided to the negative electrode active material prior to assembly of the battery using electrochemical deposition. The positive electrode active materials can comprise a layered-layered structure comprising manganese as well as nickel and/or cobalt.

Method of forming negative electrode active material, with lithium preloading

Electrochemically active material comprising a lithium metal oxide composition approximately represented by the formula LiCoNiMnO, where &#x2212;0.2&#x2264;b&#x2264;0.2, 0.2&#x2264;m&#x2264;0.45, 0.055&#x2264;n&#x2264;0.24, 0.385&#x2264;p&#x2264;0.72, and m+n+p is approximately 1 has been synthesized and assembled to batteries. The electrochemical performance of the batteries was evaluated. The lithium metal oxide composition in general comprises a first layered phase, a second layered phase and a spinel phase. A layered LiMnOphase is at least partially activated upon charging to 4.5V. In some embodiments, the material further comprises a stabilization coating covering the lithium metal oxide composition.

Lithium metal oxides with multiple phases and stable high energy electrochemical cycling

A positive electrode active material comprising a lithium rich metal oxide active composition coated with aluminum zinc oxide coating composition is disclosed. The aluminum zinc oxide can be represented by the formula AlZnO, where x is from about 0.01 to about 0.6. In some embodiments, the material can have an average voltage that is very stable with cycling, and a specific capacity of at least about 175 mAh/g and an average voltage of at least about 3.55V discharged at a rate of C/3 from 4.6V to 2V against lithium. The material can further comprise an overcoat of metal halide over the aluminum zinc oxide coating. In some embodiments, the material can have from about 1 mole percent to about 15 mole percent aluminum zinc oxide coating and from about 0.5 mole percent to about 3 mole percent aluminum halide overcoat.

High capacity cathode material with stabilizing nanocoatings

Silicon based anode active materials are described for use in lithium ion batteries. The silicon based materials are generally composites of nanoscale elemental silicon with stabilizing components that can comprise, for example, silicon oxide-carbon matrix material, inert metal coatings or combinations thereof. High surface area morphology can further contribute to the material stability when cycled in a lithium based battery. In general, the material synthesis involves a significant solution based processing step that can be designed to yield desired material properties as well as providing convenient and scalable processing.

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Pleasanton, CA, United States of America

Subramanian Venkatachalam