Long Life, High Energy Silver/Zinc Batteries

Silver/zinc batteries have been a critical component in NASA missions for decades, yet the technology has not overcome the basic flaws that limit service life. Working with Eagle-Picher Technologies, RBC succeeded in its Phase I program in solving the two major causes of early failure in silver/zinc batteries, by incorporating innovative electrode and separator components. Capacity fade on cycling was appreciably reduced translating to higher average working energy density and specific energy. Polyolefin based microporous separators were stable in KOH electrolyte giving wet-life superior to a cellophane containing laminate. Cells could be assembled in the charged state, not requiring a formation step, which is an advantage in terms of mission preparation. The proposed Phase II program will build upon the successful results of the Phase I demonstration to complete development to the point where RBC would design, assemble and deliver to NASA a higher performance silver/zinc battery for a specific NASA application. In Phase II RBC will work with Eagle-Picher Technologies and Advanced Membrane Systems, Inc. in order to complete optimization of separator and electrolyte for maximum service life. The technology will then be scaled into 40Ah, 17V batteries for the Extravehicular Mobility Unit-Primary Life Support System.