I run 2 Jeti Li Ion 5200mAh packs in my Ultra Flash with Electron gear.

Both Li Ion packs go to the CB200 to power the radio/ servos. One of the Li Ion packs also feeds the Electron gear, while the other Li Ion battery also runs the engine/ ECU.

I have over 100 flights on the UF with no issues. I can get at least 5-6 flights before a recharge, and that is only limited by the voltage drop on engine start. The other battery (Rx/ Gear) is always less depleted than the Rx/ ECU battery. Normally I keep flying until I get a failed start.

if the engine can start, I have plenty of battery power for everything else. It is self-limiting.

Paul