Rapidly Charging Battery Systems

Abstract

For rapidly charging battery systems to be fully realized, there must be [i] a cell chemistry with an adequate energy density that accepts high power charging without overheating and accelerated degradation, [ii] electricity sources that can supply the necessary charging power, [iii] battery pack designs that can handle the large charging currents while not drastically decreasing the mass and volumetric energy densities, and [iv] high power chargers. This study first explores the feasibility of these elements, and presents a particular design that was demonstrated on an electric motorcycle. The final system consists of four battery modules, totaling 1.6 kWatt-hours, a 10 kWatt charger, and an integrated circuit-based Battery Management System. A single module was rapidly charged to 90% capacity in 15 minutes, and all four modules connected in series were rapidly charged to 40% capacity. Future tests will rapidly charge the 4 modules to >90% capacity.