Following extensive safety reviews precipitated by lithium ion battery fires that grounded the 787-8 in 2013, the European Aviation Safety Agency (EASA) will now allow the batteries back on board the A350-900 for use as a backup power source.
Airbus maintains that its own lithium-ion architecture is different from that used by Boeing. Gordon McConnell, the chief designer of the A350-900, told Bloomberg in 2014 that, “from the very beginning we were fully aware of the conditions of use, and how we could mitigate any risks to zero.”
The approved lithium ion batteries, made by Saft, can provide secondary power for avionics systems and are used to start the aircraft’s auxiliary power unit (APU). With lithium ion batteries sidelined, Airbus reverted to a more conservative and well-vetted nickel-cadmium battery. However, lithium batteries are lighter and store more energy than nickel-cadmiums, making them well suited for aviation.
Airbus is still waiting for certification from the U.S. Federal Aviation Administration for the lithium-ion batteries for the A350-900, based on conditions that the U.S.-based organization issued in late 2014. Among these, are assurances that the batteries are, “sufficiently charged,” to ensure that the cells will not be permanently damaged. The FAA also stipulated that strict handling procedures be enforced to prevent short-circuiting or other unintentional impact damage.