EnergyFlux and Enerhanz manufacture good battery-powered personal heaters, according to The Wirecutter. Cozy Products, Sunbeam, Sanyo and The Body Furnace also manufacture highly rated models.
EnergyFlux and Enerhanz make rechargeable battery-powered heaters for hands. The EnergyFlux 4400mAh Hand Warmer heats for up to six hours per battery charge. It also contains a USB port for charging mobile devices. The EnergyFlux 4400mAh Hand Warmer offers multiple heat settings and charges in 4 1/2 hours.
The Enerhanz Rechargeable provides five hours of heat per battery charge. It also features a flashlight and a battery meter. Like the EnergyFlux 4400mAH Hand Warmer, this device offers several heat settings.
Cozy Products manufactures several personal warming devices, including battery-powered Cozy Feet shoe pads. Each insert has separate controls and heats up within seconds.