Amprius, Inc.

Amprius Technologies, Inc.

Constantin Ionel Stefan

Song Han

Zuqin Liu

Rainer Johannes Fasching

Jonathan Bornstein

Weijie Wang

Ghyrn E Loveness

Gregory Alan Roberts

Yi Cui

Eugene Michael Berdichevsky

Chentao Yu

Mark Charles Platshon

William S Delhagen

Daniel Seo

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 SiElayer and a conformal, denser SiElayer 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 SiElayer and a thermal CVD process to deposit the conformal layer. The silicon-rich SiEmaterial 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.

Compositionally modified silicon coatings for use in a lithium ion battery anode

Provided herein are nanostructures for lithium ion battery electrodes and methods of fabrication. In some embodiments, a nanostructure template coated with a silicon coating is provided. The silicon coating may include a non-conformal, more porous layer and a conformal, denser layer on the non-conformal, more porous layer. In some embodiments, two different deposition processes, e.g., a PECVD layer to deposit the non-conformal layer and a thermal CVD process to deposit the conformal layer, are used. Anodes including the nanostructures have longer cycle lifetimes than anodes made using either a PECVD or thermal CVD method alone.

Structurally controlled deposition of silicon onto nanowires

An electrode includes one or more intermediate layers positioned between a substrate and an electrochemically active material. Intermediate layers may be made from chromium, titanium, tantalum, tungsten, nickel, molybdenum, lithium, as well as other materials and their combinations. In certain embodiments, an active material includes one or more high capacity active materials, such as silicon, tin, and germanium. These materials tend to swell during cycling and may loose mechanical and/or electrical connection to the substrate. A flexible intermediate layer may compensate for swelling and provide a robust adhesion interface. Methods of fabricating electrodes involve forming metal silicide nanostructures.

Intermediate layers for electrode fabrication

Provided are novel electrolytes for use in rechargeable lithium ion cells containing high capacity active materials, such as silicon, germanium, tin, and/or aluminum. These novel electrolytes include one or more pyrocarbonates and, in certain embodiments, one or more fluorinated carbonates. For example, dimethyl pyrocarbonate (DMPC) may be combine with mono-fluoroethylene carbonate (FEC). Alternatively, DMPC or other pyrocarbonates may be used without any fluorinated carbonates. A weight ratio of pyrocarbonates may be between about 0% and 50%, for example, about 10%. Pyrocarbonates may be combined with other solvents, such as ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), and/or ethyl-methyl carbonate (EMC). Alternatively, pyrocarbonates may be used without such solvents. Experimental results conducted using electrochemical cells with silicon based electrodes demonstrated substantial improvements in cycle life when pyrocarbonate containing electrolytes were used in comparison with pyrocarbonate free electrolytes.

Electrolytes for rechargeable batteries

Provided are novel electrode material composite structures containing high capacity active materials formed into porous base structures. The structures also include shells that encapsulate these porous base structures. During lithiation of the active material, the shell mechanically constrains the porous base structure. The shell allows lithium ions to pass through but prevents electrolyte solvents from interacting with the encapsulated active material. In certain embodiments, the shell contains carbon, while the porous base structure contains silicon. Although silicon tends to swell during lithiation, the porosity of the base structure and/or void spaces inside the shell helps to accommodate this additional volume within the shell without breaking it or substantially increasing the overall size of the composite structure. This allows integration of the composite structures into various types of battery electrodes and cycling high capacity active materials without damaging the electrodes' internal structures and deteriorating cycling characteristics of batteries.

Composite structures containing high capacity porous active materials constrained in shells

Provided are novel multidimensional electrode structures containing high capacity active materials for use in rechargeable electrochemical cells. These structures include main support structures and multiple nanowires attached to the support structures and extending into different directions away from these supports. The active material may be deposited as a layer (uniform or non-uniform) surrounding the nanowires and, in certain embodiments, the main supports and even substrate. The active material layer may be sufficiently thin to prevent pulverization of the layer at given operating conditions. Interconnections between the electrode structures and/or substrate may be provided by overlaps formed during deposition of the active layer. Silicide-based nano wires structures may be formed on the main supports in a fluidized bed reactor by suspending the metal-containing main supports in a silicon-containing process gas. A layer of silicon may be then deposited over these silicide nanowires.

Growing community of inventors

San Jose, CA, United States of America

Constantin Ionel Stefan