golfyankeesierra,
Some years ago i was sleeping when the Ni Cd pack of my motorola vehicular caught fire whilst being recharged. Still "sleeping" i separated the pack from the unit burning slightly one finger. The pack was protected thermally and electrically but the adjacent cells (like VC10, B52, Nimrod, dangerous engines config.) were the factor of the complete destruction of the pack.
I strongly suspect the designers of these batteries are playing a very dangerous game. And the toll yet was paid by Boeing.
More to come,
In my electric bike i yet installed an APU of 300W. The battery is just for lighting and motor-gennie start.