Development, characterization, and modeling of alkaline thick film batteries

The objectives of this research are threefold: (1) To test the feasibility of application of thick-film printing technology to alkaline battery fabrication, (2) to characterize prototype cells produced using thick-film printing, and (3) to test the feasibility of producing batteries with coplanar-interdigitated electrodes. Electrode inks were formulated using active materials in powdered form, poly (ethylene oxide) as binder, graphite as conductor, and water as solvent. Zinc containing anodes and manganese dioxide cathodes were thick-film printed onto silver current collectors and assembled into cells using separator paper and potassium hydroxide electrolyte. The cells were cathode limited and had theoretical capacities between 3 and 4 mA-hrs. The highest discharge efficiency achieved was 97% of the theoretical capacity of the cathode at a rate of 1 mA/cm2. Several coplanar-interdigitated electrode designs based on the limitations of thick-film printing were investigated using current distribution modeling software. The modeling results showed that a fairly uniform current distribution was achieved with coplanar electrodes, and a battery design with coplanar-interdigitated electrodes was proposed.