PurcyP

Hi all

Recently picked up one of these, i know you can run em off DC 12v thats fine however I think in my situation it will be easier to run it off a battery.

I have found out you can run them off pretty much anything from a 7.2v nimh to a 3 cell lipo.

How long will a battery last say, 3000mah + capacity? especially in terms of a nimh, a lipo would probably last all day at 11v but im a bit wary of charging it inside the unit since there is no balance connection ?

niemand

I once measured the current for the much more tire heaters running at 60°C: about 3A (@12V)

Going from there it would mean that a 3Ah Battery would at max hold for one hour of heating. Easiest way to find out is to try it

I'm not sure if a lipo would last all day. If you could manage to lead the balancer connection outside you could charge the lipo.

Regards,
David

PurcyP

would a 3 cell lipo last longer than a 7.2v nimh if they had the same capacity due to higher voltage?

cyclonetog

Yes it would, but the battery option is really meant as a temporary power supply when you're away from your pit table.

PurcyP

Right okay cheers!


just for curiosity sake, i have a 7.2v 1800mah nimh laying about so ive connected it up and timing how long it will last, with the heaters getting to 60 degrees

cyclonetog

Have you put tyres inside them? Because the tyre, insert and wheel will absorb heat (that's the point obviously) and therefore use more energy than just the cups alone.

Also when using them you'll be starting from cold each time, so it may be more realistic to see how many 30 minute sessions it'll do, rather than 1 big constant run. Because again it'll take more energy to heat up 5 times than maintain a temperature for 2 ½ hours.