Abstract: A rechargeable backup electric heating system includes a rechargeable portable electric heater, multiple rechargeable battery packs, a rapid recharging circuit, and one or more high capacity storage batteries, from which the battery packs are recharged. The rechargeable portable electric heater has a design power output of P watts, which is determined by the BTU/hr of heat output required to maintain a target temperature in living space under prevailing outdoor temperature conditions. There are n sets of rechargeable battery packs, each having a weight of B kg. At any given time, one of the battery packs is within or attached to the heater and serving as its source of electric power, and (n?1) battery packs are being recharged by the storage battery through the recharging circuit.

Abstract: A rechargeable backup electric heating system includes a rechargeable portable electric heater, multiple rechargeable battery packs, a rapid recharging circuit, and one or more high capacity storage batteries, from which the battery packs are recharged. The rechargeable portable electric heater has a design power output of P watts, which is determined by the BTU/hr of heat output required to maintain a target temperature in living space under prevailing outdoor temperature conditions. There are n sets of rechargeable battery packs, each having a weight of B kg. At any given time, one of the battery packs is within or attached to the heater and serving as its source of electric power, and (n?1) battery packs are being recharged by the storage battery through the recharging circuit.