Patent ID: 7741815

Claim:
For use with a system for warming an intravenous fluid to be administered to a living body, which includes a case through which an intravenous fluid line extends, an apparatus comprising: a housing configured for attachment to the case, the housing including: a plurality of lithium polymer cells; a charger connected to the plurality of lithium polymer cells; a heater positioned to transfer heat to the case and attached to a thermal fuse; a fluid warmer microcontroller connected to the charger and the heater; a spread spectrum oscillator connected to the fluid warmer microcontroller; a battery condition indicator and controller connected to a fluid warmer cover closure signal and to the fluid warmer microcontroller; a first order battery protection circuit connected to elements selected from the group consisting of: the battery condition indicator and controller, at least one sensor connected to at least one of the plurality of lithium polymer cells, a cell balance circuit connected to the at least one of the plurality of lithium polymer cells, and a battery disconnect switch; a second order battery protection circuit connected to the at least one of the plurality of lithium polymer cells and the thermal fuse; and a fluid warmer overtemperature protection to sense the temperature of the case during use and connected to the thermal fuse.