Solid Hydroxyl Conducting Electrolyte

Nickel metal hydride (NiMH) batteries are the mainstay of high-energy battery systems. Currently NiMH batteries use a liquid electrolyte on a porous solid separator, which leads to batteries that not only are larger than necessary but also can release corrosive liquid KOH if the battery were damaged. This project will develop a solid electrolyte with good mobility (i.e., conductivity) for both hydroxyl ions and water molecules. The approach involves combining a very hydrophilic polymer (i.e., either water soluble or massively swollen by water) with concentrated aqueous KOH. An inorganic pseudo-cross-linking agent will be used to yield a solid material with hydroxyl and water conductivity. Commercial Applications and other Benefits as described by the awardee: A solid electrolyte should improve both the energy and power density of NiMH batteries, as well as round-trip storage efficiency, and lead to more rugged batteries. The new electrolyte also should have application to renewable energy systems, such as wind, where energy is only intermittently available and storage is required for round-the-clock operation.