By John McHale
JOPLIN, Mo. — Engineers at the Federal Systems Department of Eagle-Picher Technologies (EPT) have qualified two batteries for two high-profile missile programs.
The first, a 1-kilowatt, lightweight, lithium oxyhalide reserve battery, is for the Theater High Altitude Area Defense (THAAD) missile program, sponsored by the Atmospheric Interceptor Technology program.
This battery will supply power to the missile at half the original design weight, EPT officials say. EPT's lithium-oxyhalide battery technology will now be the baseline battery for the engineering and manufacturing development phase of THAAD.
EPT engineers have also flight-qualified a nominal 28-volt battery based on the same technology for a kill vehicle for the Boeing Ground Based Interceptor program. Experts tested both batteries to full launch and space environments, EPT officials say.
EPT officials claim their reserve battery technology provides advantages over current reserve technologies, such as:
- a reduction in battery weight over thermal or silver zinc systems of as much as 75 percent depending on load profile;
- total energy-per-weight power greater than 250 watt-hours per kilogram;
- pulse or constant power at temperatures colder than -32 degrees Celsius even after 10 years of storage; and
- low operating temperatures, which enables designers to place the batteries near heat-sensitive electronics.
Making the company's lithium oxyhalide reserve technology possible was the development of an efficient electrolyte delivery system, advanced electrodes, and electrode separators, EPT officials explain. EPT engineers have developed thin electrode technology that has high-energy utilization and low electrical impedance.
They also have developed a composite separator that combines high electrolyte absorption with strength integrity. This combination can quickly absorb electrolytes while withstanding the fluid dynamics of a rapid activation, EPT officials claim.
"Lithium oxyhalide is the battery chemistry," says an EPT official. "This type of battery is capable of providing high currents for short times in a small package. As with any other chemistry, the battery performs better warm than at -32 C. The reason that this type of chemistry is preferable to others is the fact that it can provide the higher currents at lower weights.
"This battery chemistry is used in many applications," he explains. "The reserve versions of it are only practical for uses that require five to 20 minutes of high power once. This battery is not rechargeable."
For more information on Eagle-Picher Technologies contact Brian Duckworth by phone at 417-623-8000 or on the World Wide Web at http: www.epi-tech.com.