Processes for Manufacturing and Recharging Lithium Polymer Batteries to Extend Life Cycle

Our goal is a major advancement in the life cycle of rechargeable, solid-state lithium/polymer batteries -- a factor of ten improvement to 1000's of recharge cycles. We will achieve this goal by attacking various problems of degradation at the electrode/ electrolyte interfaces, a primary factor in limiting rechargeable life and broader commercial value of these batteries. Identification and understanding of the various degradation mechanisms will lead to improved fabrication processes to mitigate degradation. In Phase I, we propose to identify and model the passivation mechanisms at the anode/electrolyte interface and modify fabrication processes to mitigate passivation. Our Phase I effort uniquely synthesizes interfacial impedance modeling, supplementary physical (XPS) analysis, and mechanistic modeling with advanced battery technology and manufacturing processes developed by our teammate, Alliant Techsystems. During Phase II, we will apply the Phase I methods to the cathode interfaces and fabrication processes. Results of this proejct are batteries with greatly improved life cycle, and possibly related products such as a smart recharger or diagnostic software. We expect to license Phase III products or processes to Alliant Techsystems. Anticipated Benefits: With specific energy ratings 2 to 5 times greater than present batteries, rechargeable lithium/polymer-electrolyte batteries are an attractive candidate for portable applications. There is a large commercial market for high energy density, long life batteries for medical implant devices, portable communicaion, global positioning, laptop computer, and electric vehicle applications. Military applications include seconday batteries on sattelites and backpacks where the benefits are reduced cost through smaller size and extended recycle life.