Traditionally, aircraft power system use passive power converter coupled with NiCad battery to provide power to 28Vdc buses from main AC network. This solution is very mature, but power quality from this architecture is low and impact avionics loads designs and overall system reliability.

Recent progress in power electronics and lithium –ion batteries allows higher power density compared to traditional passive approach. The new solutions allow considerable performances enhancement and weight/volume savings (feeder, loads…) and better reliability at aircraft level.

Management of lithium battery charge and discharge imposes multiples protections in order to insure a proper behaviour during all possible scenarios and to ensure safety, even during abusive conditions. No break power transfer coordination is also a challenge at architecture level.