787 Batteries and Chargers - Part 1

[RR_NDB]

Cause or symtom?

RetiredF4:

Hi Franzl,

Sequence in ANA, very probably:

1) High temp at cells (to be understood why)
2) Cell #3, plus terminal (or # 4 minus terminal) shorted to battery case
3) Unlimited current (short circuit) flowed to aircraft ground return via battery case grounding wire. (~12 V at start of event)
4) Current of hundreds of Amps fused this battery case grounding wire.