Composite Cathode Structure/Property Relationships

Abstract

Battery active materials are routinely evaluated via the electrochemical performance of their composite electrodes which are prepared with standard formulations and routine processing conditions. The relationship between electrochemical responses and these experimental variables are not commonly explored. Mechanical properties and their relationship to durability are almost never considered. We therefore offer some quite basic studies of the effects of formulation on these properties. Electrochemical and mechanical properties of composites across a broad formulation range are provided for the most common Li-Ion chemistry - LiCoO2 electroactive particles with PVDF binders. Mechanical characterizations include evaluations of both the constituent materials and the porous electrode structures. We will show that composite electrode designs which optimize mechanical durability and ruggedness will degrade electrochemical performance for these LiCoO2/PVDF binder- based systems.