Zenlabs Energy, Inc.

Envia Systems, Inc.

Ionblox, Inc.

University of Delaware

Charan Masarapu

Herman Adrian Lopez

Sujeet Kumar

Haixia Deng

Yongbong Han

Yogesh Kumar Anguchamy

Subramanian Venkatachalam

Sanjeev Sharma

Xianyu Iris Li

Pedro A Hernandez-Gallegos

Bingqing Wei

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

Silicon oxide based materials, including composites with various electrical conductive compositions, are formulated into desirable anodes. The anodes can be effectively combined into lithium ion batteries with high capacity cathode materials. In some formulations, supplemental lithium can be used to stabilize cycling as well as to reduce effects of first cycle irreversible capacity loss. Batteries are described with surprisingly good cycling properties with good specific capacities with respect to both cathode active weights and anode active weights.

Silicon oxide based high capacity anode materials for lithium ion batteries

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

Composite silicon based materials are described that are effective active materials for lithium ion batteries. The composite materials comprise processed, e.g., high energy mechanically milled, silicon suboxide and graphitic carbon in which at least a portion of the graphitic carbon is exfoliated into graphene sheets. The composite materials have a relatively large surface area, a high specific capacity against lithium, and good cycling with lithium metal oxide cathode materials. The composite materials can be effectively formed with a two-step high energy mechanical milling process. In the first milling process, silicon suboxide can be milled to form processed silicon suboxide, which may or may not exhibit crystalline silicon x-ray diffraction. In the second milling step, the processed silicon suboxide is milled with graphitic carbon. Composite materials with a high specific capacity and good cycling can be obtained in particular with balancing of the processing conditions.

Methods for forming silicon-silicon oxide-carbon composites for lithium ion cell electrodes

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

Lithium ions cell designs with high capacity anode materials and high cell capacities

Composite silicon based materials are described that are effective active materials for lithium ion batteries. The composite materials comprise processed, e.g., high energy mechanically milled, silicon suboxide and graphitic carbon in which at least a portion of the graphitic carbon is exfoliated into graphene sheets. The composite materials have a relatively large surface area, a high specific capacity against lithium, and good cycling with lithium metal oxide cathode materials. The composite materials can be effectively formed with a two step high energy mechanical milling process. In the first milling process, silicon suboxide can be milled to form processed silicon suboxide, which may or may not exhibit crystalline silicon x-ray diffraction. In the second milling step, the processed silicon suboxide is milled with graphitic carbon. Composite materials with a high specific capacity and good cycling can be obtained in particular with balancing of the processing conditions.

Silicon-silicon oxide-carbon composites for lithium battery electrodes and methods for forming the composites

Battery designs with high capacity anode materials to achieve desirable cycling properties

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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Fremont, CA, United States of America

Charan Masarapu