What kind of testing does the European Space Battery Test Centre laboratory carry out?
Space battery testing is a long-term business. A battery intended for a telecommunication service is required to go on operating for more than 15 years without a hitch. There are few options for accelerating such testing when a new battery design arises so it must be performed in real time, including thousands of charge/discharge cycles.
Tests takes place in representative environmental conditions, including exposure to vacuum conditions and thermal extremes. Batteries or cells are put through their paces on a set of automated test benches. Temperature shifts can affect charge rates, hastening degradation. Researchers are interested in observing battery phenomena as they age including any self-discharge tendencies and memory effects where a semi-discharged battery 'forgets' to recharge to full capacity.
Batteries are made from individual power cells which have to be carefully connected together in series and parallel. This can be a difficult art to master; cells may go out of balance, causing high voltages and short circuits. The Test Centre possesses sophisticated software tools however to perform model tests on the effectiveness of battery design and also power management techniques in advance of physical testing.
Space battery R&D seeks to improve their specific energy of batteries, so more energy can be stored within less mass. They also qualify battery designs for flight, including all European batteries for the International Space Station.
The Test Centre performs a similar gamut of tests on fuel cells, which operate in the same electrochemical basis as batteries but run an open rather than closed basis. The fuel cell system operating on the International Space Station combines hydrogen and oxygen, producing water as a byproduct.
This is seen as having great potential for future human colonies located much further afield. But because fuel cells will be a life-critical part of such missions they require even more elaborate long-duration testing.
Last update: 29 September 2009