Solid State Electrolyte
Replacing flammable electrolytes with solid-state electrolyte is an effective approach to alleviate the safety concerns of the nonaqueous Li-ion batteries. Our research focuses on studying the chemical and electrochemical reactions between the electrode/electrolyte interfaces and develop materials strategies to reduce the interfacial resistance and improve the rate capability and cycling stability of the solid-state batteries.
Developing Solid-State Electrolyte for All-Solid-State Li-Ion Batteries
All-solid-state lithium ion batteries (ASS-LIBs) have received increased attention for the potential advantages over traditional lithium ion batteries, such as safety and significant promise of scale-up. Solid state electrolytes are the key to the development of ASS-LIBs. We have developed both NASICON and garnet structured solid state electrolytes with a high quality by a low-cost and facile method.
Studying Solid state electrolyte-electrode interfaces
Solid state electrolyte-electrode interface issue has been a critical challenge hindering the application of all solid state battery. There are a number of failure modes such as interfacial delamination and reaction of electrodes into electrically/ionically insulating phases, which increase interfacial resistance and result in significant capacity fading during cycling. Besides, notorious dendrite nucleation and growth at the electrolyte-electrode interface also occur in the solid electrolyte system, leading to catastrophic electrical short. To solve these issues, the failure mechanism at the interface need to be revealed. We use time-resolved impedance and overpotential profiles to evaluate the interface formation and dendrite penetration. To investigate degradation phenomena, we monitor electrochemical reaction at the interface by in situ X-ray absorption near edge structure (XANES). Based on better understanding of interfacial behaviour, more efficient modifications can be realized to improve the performance of all solid state battery.