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For 70 years Yardney has been a leader in specialty battery and energy systems for military, space, avionics, weapon systems and undersea vehicles. In addition to battery systems, Yardney also delivers hybrid systems for ground, space, undersea and avionic applications. The beauty of hybrid systems, combining energy sources such as batteries, capacitors, fuel cells and solar, is that they can be used to optimize energy and power density, and with proper design, the systems can also lead to longevity of components and an overall cost savings. For ground applications, utilization of hybrid systems can assist in conservation of fuel by making vehicle applications more efficient. For space applications, satisfying pulses can be improved by a capacitor and battery hybrid energy storage system. To optimize aircraft performance and decrease operating costs, avionics are beginning to move towards more electric aircrafts (MEA).

Experimental Lithium-ion (Li-ion) cells were constructed with three different types of Li-ion cathode materials and two different graphitic anodes. The cathode materials were lithium nickel cobalt aluminum oxide, LiNiXCoYAlZO2 (NCA), lithium nickel cobalt manganese oxide, LiNiXCoYMnZO2 (NCM), and lithium iron phosphate, LiFePO4 (FEP). The two graphitic anodes differed only in particle size. The cells were built in lots identified by their cathode and anode materials. The goal was to develop a battery for Naval Aviation applications. Initial testing favored the cells built with an NCM cathode. Further testing was per MIL-PRF-8565/14(AS) with Amendment 1, which resulted in a reduced voltage range during testing favoring the NCA lots. The cells were tested under two different types of cycle life conditions. In both cases, the NCA lots fared best. The NCA lots also had the lowest DC Resistance (DC Res) results (both ≤10 mΩ).

Yardney Technical Products is developing a high energy density Li-ion cell tailored for NASA's Extravehicular Mobility Unit battery. The goal of the program is to develop a Li-ion technology which offers long storage and cycle life in a system which provides energy density and exercise performance comparable to the current 6.7kg Zn-AgO battery. The Zinc-Silver Oxide cells which are most commonly used in this application provide 400 Wh/l with a 32 cycle life at 26.6Ah and 1.55V with a rated wet life of 425 days. To improve the energy density of the Li-ion cells we have focused on improving the energy density of its components. In addition to using thin metal foil current collectors, the energy density of the cathode material was improved by utilizing a high capacity Co doped nickel oxide material. Further efforts have focused on developing a more energy dense carbonaceous anode material. The results of this effort are reviewed.

Lithium-ion batteries with their high specific energy and energy density, offer a unique weight and volume solution to aerospace requirements. Under sponsorship of the USAF, Yardney Technical Products, Inc. is developing a prismatic 20 Ah Li-ion cell that delivers a specific energy of 130 Wh/kg and energy density of 250 Wh/l. These cells also demonstrate high pulse rate capability and, with design improvements, will result in batteries that meet or exceed the demanding requirements of aerospace applications. This paper will present the design considerations for these first generation cells as well as the results of performance and life testing.

Lithium-ion batteries have proven to be intrinsically safe, capable of long cycle life and environmentally friendly. These batteries provide high energy density and a low rate of self-discharge. Yardney has developed 2, 3, 5 and 20Ah prismatic cell designs in both metal and lightweight plastic cases. Prismatic cells are more space efficient then cylindrical cells and require less expensive tooling for manufacture. For high-rate pulse-power applications, Yardney has developed a bipolar lithium-ion system which can deliver more than 3000 charge / discharge cycles of pulse-power and five-second pulses at current densities as high as 70mA/cm2. The present bipolar effort is focused on development of a 270V bipolar battery for Aerospace and Aircraft Applications.

The demand for increased performance from batteries in missiles, space applications and torpedo propulsion has generated extensive battery development over the years. Dramatic improvements in the specific energy capability of the Silver Zinc System can be expected only through the development of new materials, novel approaches and/or new concepts in the design of the Silver Zinc batteries. One concept that Yardney is currently re-evaluating is bipolar construction. The major incentive for the use of bipolar cells in a pile configuration is the elimination of intercell connectors, other heavy current carrying structural elements and some of the cell containment features. This allows for substantial weight and size reduction, while increasing the specific power/energy density of the battery. Much of this work was originally developed by Yardney in the late 1960's to early 1970's.