warming batteries
 

What is the most effective temperature to warm batteries up to, to lower IR.

Warming by high discharge / charge rate is the only legal way to warm batteries.

It's not legal to warm using a heating blanket. Plus this can be dangerous. Every battery I've seen puff and explode was from someone trying to warm their batteries using a heating blanket.

Warming batteries to increase IR? Wow, never heard that one before.

Keep knocking on the rule-makers door eventually someone's going to answer you.

Everybody I have ever seen do this basically had no reason to, they were either good enough to not need it or so hopeless it couldn't possibly help. Finishing order is on driver skill, car tuning, and a nice big helping of luck. Having your battery 5 degrees warmer makes no difference. 30 degrees, maybe, but they are starting to limit charging amps and check battery temps at big races during tech inspection.

Optimal temperature is 45 deg C.

Thanks. Your right about the driving part. At our track they don't check voltage or temperature, thought it might help keep the batteries from dropping off as much at the end of the race.

If you have half an A main full of drivers with lap averages top 5,10, and 20 within a tenth or so on a wintertime carpet track with cool temps, it can make a difference. At a COLD carpet NATS with a tech table near a door, rumor has it you could charge at 40 amps and pack would be cold by the time you got to the top of the line in tech. ;) They stopped temping packs, probably because the tech area was so cold it didn't matter.

All I can tell you, most of the fastest guys were coming to tech at the last possible moments. My guess is to keep some heat in the packs.

But at a NATS, you'll do almost anything to get those last couple 100ths of a second. Since the ambient temp at the tech area was 50 degrees, I'm sure the potential gain was slightly magnified..

On a club level, charge at 8 amps and don't bother ruining good packs...

Unless you're running open Mod, any drop off will likely be the temp of the motor increasing, along with it's resistance.

Skiddins