High Capacity Rate Capable Aerosol Jet Printed Li‐Ion Battery Cathode

A thick (170 μm) LiFePO 4 cathode is fabricated through aerosol jet printing. The printed cathode displays a pattern of aligned high aspect ratio needles which, in cross section, produce micron scale channels. These channels surround regions of LiFePO 4 that possess submicron pores. When tested in half cell configuration versus a Li‐foil anode, the specific discharge capacity of the printed cathode is 151 mAh g −1 at a C/15 rate and 105 mAh g −1 at 1C. These values correspond to area normalized discharge capacities of 2.5 and 1.7 mAh cm −2 at current densities of 0.2 and 2.4 mA cm −2 , respectively. In a 50 cycle constant current charge/discharge test, the discharge capacity is stable, retaining 89% of its initial C/5 capacity. These results suggest that aerosol jet deposition is a promising printing technique for fabricating high capacity, rate capable, Li‐ion battery cathodes.