Centrifugally Cast Cathodes for High-Power, High-Capacity Lithium-Ion Batteries

Boundless' new proprietary process to manufacture high-density battery electrodes promises both high energy storage capacity and high power capability. The breakthrough technology combines novel high-porosity polymeric binders and a new centrifugal casting technique to yield dense, high-capacity cathodes while maintaining ion mobility. Common cathode densification methods using traditional binders reduce porosity and ionic flux even though voids constitute nearly 50% of an undensified cathode. The project is expected to demonstrate that Boundless' proprietary high-porosity polymer will maintain sufficient porosity to support the high levels of ionic mobility and fast charge/discharge. Preliminary tests showed increases in active material density of 33% and increases in electrolyte wet-out of 80%, indicating probable enhancement of ion mobility and rate capacity. Centrifugal casting of battery electrodes is an entirely new concept that is enabled by the development of the new high-porosity polymeric binder material. This novel material, entirely distinct from traditional systems like those from Bellcore and Sony, has >80% void content, sub-micron pore sizes and substantial mechanical strength. With centrifugal casting, electrode porosity, mechanical integrity and packing density (specific capacity) are simultaneously optimized. Electrode capacity (mAh/cc) is projected to increase 50 to 100%, corresponding to higher cell energy density (Wh/liter).