Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Battery designs are provided that exhibit commercially suitable cycling properties for consumer electronics with silicon based active materials in the electrodes. The batteries can have stacked or wound electrodes and suitable electrode designs.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Electrolytes are described with additives that provide good shelf life with improved cycling stability properties. The electrolytes can provide appropriate high voltage stability for high capacity positive electrode active materials. The core electrolyte generally can comprise from about 1.1M to about 2.5M lithium electrolyte salt and a solvent that consists essentially of fluoroethylene carbonate and/or ethylene carbonate, dimethyl carbonate and optionally no more than about 40 volume percent methyl ethyl carbonate, and wherein the lithium electrolyte salt is selected from the group consisting of LiPF6, LiBF4 and combinations thereof. Desirable stabilizing additives include, for example, dimethyl methylphosphonate, thiophene or thiophene derivatives, and/or LiF with an anion complexing agent.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Electrolytes are described with additives that provide good shelf life with improved cycling stability properties. The electrolytes can provide appropriate high voltage stability for high capacity positive electrode active materials. The core electrolyte generally can comprise from about 1.1M to about 2.5M lithium electrolyte salt and a solvent that consists essentially of fluoroethylene carbonate and/or ethylene carbonate, dimethyl carbonate and optionally no more than about 40 volume percent methyl ethyl carbonate, and wherein the lithium electrolyte salt is selected from the group consisting of LiPF6, LiBF4 and combinations thereof. Desirable stabilizing additives include, for example, dimethyl methylphosphonate, thiophene or thiophene derivatives, and/or LiF with an anion complexing agent.

Abstract: 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.

Abstract: 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.

Abstract: Electrochemically active material comprising a lithium metal oxide composition approximately represented by the formula Li1+bComNinMnpO(2), where ?0.2?b?0.2, 0.2?m?0.45, 0.055?n?0.24, 0.385?p?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 Li2MnO3 phase 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.

Abstract: Batteries with high energy and high capacity are described that have a long cycle life upon cycling at a moderate discharge rate. Specifically, the batteries may have a room temperature fifth cycle discharge specific energy of at least about 175 Wh/kg discharged at a C/3 discharge rate from 4.2V to 2.5V. Additionally, the batteries can maintain at least about 70% discharge capacity at 1000 cycles relative to the fifth cycle, with the battery being discharged from 4.2V to 2.5V at a C/2 rate from the fifth cycle through the 1000th cycle. In some embodiment, the positive electrode of the battery comprises a lithium intercalation composition with optional metal fluoride coating. Stabilizing additive maybe added to the electrolyte of the battery to further improve the battery performance. The batteries are particularly suitable for use in electric vehicles.

Abstract: 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.

Abstract: 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.

Abstract: Positive electrode active materials are described that have a high tap density and high specific discharge capacity upon cycling at room temperature and at a moderate discharge rate. Some materials of interest have the formula Li1+xNi?Mn?Co?O2, where x ranges from about 0.05 to about 0.25, ? ranges from about 0.1 to about 0.4, ? ranges from about 0.4 to about 0.65, and ? ranges from about 0.05 to about 0.3. The materials can be coated with a metal fluoride to improve the performance of the materials especially upon cycling. Also, the coated materials can exhibit a very significant decrease in the irreversible capacity lose upon the first charge and discharge of the battery.