Launch vehicles require a suite of batteries to meet the power demands of a variety of on board equipment. Although launch vehicle missions are relatively short compared to those of spacecraft and only occur once. Many launch suppliers are converting to Lithium-ion battery technology (from primary and older secondary chemistries). It has been found that Lithium-ion can offer comparable or superior energy and power densities with the added benefit of simplifying ground operations. Lithium-ion has far superior cycle and shelf life meaning that launch scrubs and extended pad stays can be endured without labour intensive battery analysis and replacement.
ABSL have provided Launch vehicle batteries required by many different launch vehicle systems. The avionics battery powers the ‘brain’ of the vehicle including navigation and communication equipment. These batteries tend to have relatively low power requirements but good energy density as operation is sustained throughout the entire flight during the operation of each rocket stage. Pyrotechnic and Flight Termination System (FTS) batteries generally have a very low background load throughout the flight with a number of short duration high current pulses to operate ordinance. ABSL has a number of both high power and high energy cells that can be employed for launcher missions.
Thrust Vector Control (TVC) systems provide directional control of rocket engines on launch vehicles. To access cost, safety and weight benefits over heritage (hydraulic) systems, many launch vehicle providers are looking to use fully electric TVC systems powered by high voltage battery systems. Working with high voltage batteries raises safety concerns on the ground as such voltage levels can be lethal if batteries are mishandled. Furthermore, to successfully operate high voltage systems reliably in space, many technical challenges must be overcome. In particular, the risk of corona at the low pressures encountered during launch is key. Indeed, some battery manufacturers and programs have failed during thermal vacuum testing following arcing events invoking catastrophic failure.
ABSL is unique in the industry in having engineered a number of innovative high voltage battery design characteristics that have allowed the formal space qualification of a 270V Lithium-ion battery. ABSL put the battery through a stringent space qualification program including harsh vibration testing as well as thermal vacuum testing. The battery was able to provide almost 6kW of sustained power with capability to provide peak loads that were much higher (details available on request). Following successful tests of the qualification model in 2006, flight models were built, acceptance tested and delivered to the customer. The 270V TVC battery has since been tested in an end-to-end full system level configuration and was shown to easily handle high in-rush currents encountered during operation. The maiden flight of the vehicle using this TVC battery (as well as a suite of other ABSL Lithium-ion batteries providing other functionality) is due in early 2009.