Bipolar Nickel-Metal Hydride Aircraft Battery with Increased Capacity and Improved Low Temperature Performance

Electro Energy, Inc. (EEI) has developed a bipolar Ni-MH wafer cell design that has the advantages of reduced weight, with increased capacity, high power and low temperature capabilities over conventional Ni-MH and competing technologies. These advantages make the EEI bipolar Ni-MH the battery of choice to replace the present F16/F18 and other military aircraft batteries. EEI's present F-16 battery has 10% reduced weight in the same volume as the existing lead-acid battery, while having 2½ times the capacity. EEI's design of parallel stacks of thin wafer cells results in increased electrode surface area leading to improved high-rate and low temperature capability. The design has shown to be capable of operating at the Air Force minimum temperature requirement of -40°C. This has been achieved by optimizing each of the following variables: 1) metal-hydride alloy; 2) electrode capacity and surface area relationship; and 3) electrolyte composition. Supported by U.S. Air Force Manufacturing Technology Programs, EEI has focused on improving the performance of this battery, while scaling-up the manufacturing processes to meet the demands of the DoD and provide a cost competitive battery.