Abstract: Provided herein are nanostructures for lithium ion battery electrodes and methods of fabrication. In some embodiments, a nanostructure template coated with a silicon-based coating is provided. The silicon coating may include a non-conformal, more porous silicon-rich SiEx layer and a conformal, denser SiEx layer on the non-conformal, more porous layer. In some embodiments, two different deposition processes are used: a PECVD layer to deposit the non-conformal, silicon-rich SiEx layer and a thermal CVD process to deposit the conformal layer. The silicon-rich SiEx material prevents silicon crystalline domain growth, limits macroscopic swelling, increases lithium diffusion rate and enhances significantly battery life during lithium ion battery cycle of charge and discharge.

Abstract: Provided herein are nanostructures for lithium ion battery electrodes and methods of fabrication. In some embodiments, a nanostructure template coated with a silicon-based coating is provided. The silicon coating may include a non-conformal, more porous silicon-rich SiEx layer and a conformal, denser SiEx layer on the non-conformal, more porous layer. In some embodiments, two different deposition processes are used: a PECVD layer to deposit the non-conformal, silicon-rich SiEx layer and a thermal CVD process to deposit the conformal layer. The silicon-rich SiEx material prevents silicon crystalline domain growth, limits macroscopic swelling, increases lithium diffusion rate and enhances significantly battery life during lithium ion battery cycle of charge and discharge.

Abstract: The present invention provides novel and inexpensive compositions including carboxylic acids as an efficient surface-modifying agent for a silicon-based electrode, useful in constructing a novel lithium ion secondary battery.