Laser-printed thick-film electrodes for solid-state rechargeable Li-ion microbatteries

Laser-printed thick-film electrodes (LiCoO2 Cathode and carbon anode) are deposited onto metallic current collectors for fabricating Li-ion microbatteries. These microbatteries demonstrate a significantly higher discharge capacity, power and energy densities than those made by sputter-deposited thin-film techniques. This increased performance is attributed to the porous structure of the laser-printed electrodes, which allows improved ionic and electronic transport through the thick electrodes (similar to 100 mu m) without a significant increase in internal resistance. These laser-printed electrodes are separated by a laser-cut porous membrane impregnated with a gel polymer electrolyte (GPE) in order to build mm-size scale solid-state rechargeable Li-ion microbatteries (LiCoO2/GPE/carbon). The resulting packaged microbatteries exhibit a power density of similar to 38 mW cm(-2) with a discharge capacity of similar to 102 mu Ah cm(-2) at a high discharge rate of 10 mA cm(-2). The laser-printed microbatteries also exhibit discharge capacities in excess of 2500 mu Ah cm(-2) at a current density of 100 mu A cm(-2). This is over an order of magnitude higher than that observed for sputter-deposited thin-film microbatteries (similar to 160 mu Ah cm(-2)). Published by Elsevier B.V.