Other than taking a voltage test from each cell is there any other way to find a bad cell? All cells are in the 8.13V but I know one is bad. My car keeps accelerating very slow on the gas engine only most of the time. Like a manual trans in 2nd gear. And the battery is going from charged to dead in seconds. But I'm not getting any warring lights?
Without DTC, it is hard to be sure that the problem is a particular cell, although the sudden jumps from low to high on the SOC is a certain sign of impending failure. Does the battery fan come on loudly? Is it clean? You are in a cool place so it is probably not overheating now, but those symptoms can be heat related. The best way (IMHO) to check for cell status under driving conditions is to use the mini VCI tool (eBay) and look at the individual internal resistances. The ScanGaugeII will also do that. The cell voltages would be more likely to be noticeably divergent at low SOC, so maybe you can measure things when the SOC shows low bars.
