Originally Posted by Zeta30
I just tried out a new set of 4 Gens Ace 2200mAh 30c batteries. They were a great boost over my aging set of Flightmax. They all came in perfectly balanced and the internal resistance on each cell was 1 ohm resting internal resistance. I just need to get them broken in so I can see what they can really do.
1 ohm is huge
. Imagine these things flying around under 15 amps load with a total 3 ohm resistance. This means the battery itself would burn 675 Watts (RI^2). All this power would be dissipated as heat, which would make the battery melt in less than a minute.
good, new lipos should have between 0.01 and 0.03 ohm internal resistance (each cell). B-grade lipos may go up to 0.08 ohm/cell, but anything more than than means lots of heat and poor performance.
Speaking of bad lipos, I just got a BatteryHobby 3s from ehirobo and it came more than 0.5V out of balance (3.46, 3.86, 3.89V)
. It was so bad, my charger almost caught fire trying to balance it
. I had to slow-charge the first cell individually on a separate 1S charger until it got to the same voltage as the others. I'll give it a try tomorrow in my BA and see if it works at all.