Biomaterials-driven synthesis is generally performed at low temperatures and under aqueous conditions, making the process economical and environmentally friendly. However, biomaterials are not fully adopted for large-scale synthesis or manufacturing of electronic materials due to their handling complexity and unknown effects on the material’s properties. Therefore, a systematic understanding of the structure of biomaterials and their role in the device is critical to making bioinspired synthesis methods scalable and easily controllable. Our group utilizes a naturally abundant material, bacteria, to fabricate battery electrodes. We are motivated by the natural process of forming fossils from living organisms when manufacturing battery electrodes. We expect the bioinspired process to make battery material fabrication more sustainable and environmentally friendly, reducing our reliance on natural resources.

Solid electrolytes for lithium batteries have advantages over liquid electrolytes because of their inherent safety against flammability and their wider voltage window. However, solid electrolytes have two barriers that limit power performance and battery cycle life: (1) their low ionic conductivity and (2) the lack of mechanical flexibility to maintain continuous interfacial contact with electrodes. Our group focuses on a composite electrolyte system that contains both flexible polymers and high-conductivity lithium conductors to address these issues. We study how the conductivity of the composite electrolyte is affected by the composite structure, polymer formulation, and mechanical cycling. We also focus on how the microstructure of composite electrolytes evolves under repetitive compressive force to understand its impact on the cycle life of solid-state batteries. Our ultimate goal is to build a safe and long-lasting battery by overcoming the major challenges of solid electrolytes.

Water-based LIB will provide an inexpensive, safe, and environmentally benign power source. The electrochemical stability window of an aqueous electrolyte (1.23 V) can be broadened to as much as 4.0 V by utilizing a highly concentrated water-in-salt electrolyte (WiSE). At present, real-world WiSE applications suffer from high cathodic limits (the instability of electrolytes against anodes) that significantly restrict the use of these high-capacity low voltage anodes. Our research group tackles this challenge by integrating an interfacial layer into the anode to minimize the water electrolysis reaction. We aim to obtain a better understanding of the transport properties of the solid-electrolyte interphase (SEI) layers in a new type of aqueous electrolyte, WiSE, thus we can rationally design an SEI promoter layer based on these learnings.