Hi!
I have build thermostat controlled heater to my lipos.
Three pairs of thoses in series at battery voltage(48V): http://www.ebay.com/itm/Universal-Motorcycle-ATV-Heated-Hot-Hand-Grips-Inserts-Handlebar-Hand-Warmer-Kit-/301803890817?hash=item4644e9e881:g:gQMAAOSwiwVWTsOC&vxp=mtr
Can't...