Hi,
RetiredF4:
Could the problem be related to the amount of composite materials of the aircraft structure with regards to static charging when in flight or due to insufficient grounding of the cell when on ground after flight?
When you put electric power Systems managed by sensitive electronic circuitry you must look carefully to Electromagnetic Interference and Compatibility. (EMI/EMC).
Grounding and Shielding is another issue in the innovative 787 design. The issue of fuel storage in the plane deserved special attention like "inerting" and carefull structures bonding, etc.
The ANA 747 hit by a bolt just after takeoff is an example of what we are subject and the Concorde yaw damper being interfered by HF transmitter keying (as mentioned by Cj in AF447 threads) are to be remembered.
Normally LOW IMPEDANCE circuitry are less prone to be interfered. But:
1) High current and possibly Spikes could interfere in analog and even in digital circuitry.
2) We have inside the battery case more than 500 (estimating) devices and it seems also a high current switch. The two PCB certainly has a "safety role".
I would not consider EMI/EMC in this cases (batteries) as priorities to be looked.
But when investigating, specially when you are in the dark WRT to WHAT and WHY as put by NTSB chief you must look to everything. Even after you find a smoking gun. You may have more than one design problem. The FAA review has this merit. Will spot in other possible issues.
Your comment is pertinent to a new design using "less metal".