Zenlabs Energy, Inc.

Envia Systems, Inc.

Ionblox, Inc.

Eocell Limited

Yongbong Han

Haixia Deng

Charan Masarapu

Yogesh Kumar Anguchamy

Sujeet Kumar

Herman Adrian Lopez

Subramanian Venkatachalam

Yuriy Borisovich Matus

Michael Pak

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

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

A method for producing a volume change compensated (SSLC) material is disclosed. An initially prelithiated SSLC material is produced and delithiated to produce a delithiated SSLC material. Perform at least one iteration involving: (a) re-prelithiating the delithiated SSLC material to produce a re-prelithiated SSLC material; and (b) delithiating the re-prelithiated SSLC material produced in (a). At least one of the following is satisfied: (i) prior to performing the at least one iteration the initially prelithiated SSLC material is essentially completely lithiated; and (ii) at least one iteration produces a re-prelithiated SSLC material that is essentially completely prelithiated. In a final iteration, delithiating the re-prelithiated SSLC material produced in (a) completely delithiates the re-prelithiated SSLC material to produce the volume change compensated SSLC material. The aforesaid process is performed ex situ with respect to fabrication of an anode that contains the produced volume change compensated SSLC material.

Volume change compensated silicon-silicon oxide-lithium composite material having nano silicon particles embedded in a silicon:silicon lithium silicate composite matrix, and cyclical ex-situ manufacturing processes

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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San Francisco, CA, United States of America

Yongbong Han