787 Batteries and Chargers - Part 1

[RR_NDB]

gums:

In a plane that weighs as much as the 787, a few pounds for an "older", but more safe battery seems a good trade-off.

My friends who served in the 'stan and Iraq told me war stories about those "new" batteries. The temperatures and charging systems did not help, so they went back to older batteries.

In my mind, it ain't worth the extra battery capacity to require expensive charging systems and such. Then there's the requirement to have a good fire extinguishing system if one of the suckers goes into thermal runaway.

The grounding of the 787 fleet an it´s consequences strongly supports your rationale.

It´s unclear to me the size of the gain in using these batteries. We need to understand better the trade-offs and quantify.

The designers probably required to use them in the 787. We need to check why. Which were/are the dominant reasons?

May be the very high peak current of the new batteries (due low internal resistance) were important for the high energy consumption of the 787?

On maintenance aspects and risks it´s clear Boeing heard the promises of the suppliers (Batt and chargers) installing it close to Electronic Equipment without elaborated safety schemes in case of major failures like the ones that occurred.