Silver-Metal-Hydride Cells for Portable, Rechargeable, Energy Storage

It is proposed to demonstrate the performance characteristics of a high energy density rechargeable battery based on the silver metal hydride system with an energy density of 80 Wh/Kg and over 200 Wh/l. These values are almost three times that of Pb/Acid and more than 2 times that of Ni/Cd. Ovonic Silver/MH system has been under development for some time at OBC. Some preliminary data exists at OBC on a vented version of this system. The potential capability of this system has been demonstrated in this configuration. The Ovonic Nickel metal hydride has been demonstrated to have good energy density, easy manufacturability and environmentally benign disposition. By extrapolation it is expected that the silver metal hydride system proposed will retain all the performance attributes of the nickel metal hydride system. By utilizing some of the key high specific capacity negative electrodes and high energy density silver electrodes it is proposed to fabricate and test prismatic starved cells of capacity greater than 7Ah yielding 80 Wh/kg and over 200/liter in volumetric energy density. They will be tested for capacity, rate capability, temperature performance etc. It is proposed to proceed into Phase II with fabrication and testing of large number of individual prismatic starved cells. Once reproducible results are obtained fabrication and testing of battery modules using these individual cells will be taken up as one of the tasks in Phase II.