Abstract: In a preferred embodiment, designed for gas-efficient automobiles having low power alternators having insufficient power and utilizing a battery of insufficient voltage to operate both the automobile necessary circuitry and heater as to heat the automobile space within a satisfactory short time interval of a few minutes, a circuitry of conventional type but additionally including in series with a low voltage relay, another voltage relay switch which when energized turns on current to an electromagnetic relay normally open switch to close the switch to thereby connect a second battery positive terminal to the output terminal of the alternator for thereby recharging the second battery, and the normally open switch normally connecting the positive terminal of the second battery to a large supplemental heater when the normally open switch is in an open state, whereby when the regular low capacity battery is at low voltage the supplemental heater quickly heats the automobile space, and at elevated voltage the conv

Abstract: In a preferred embodiment, a battery embodying and driven vacuum cleaner having a battery-recharging unit, having a pivoted and pivotably-driven driven wheel indirectly driven by an electric motor powered by the battery, and having other free-wheeling support wheels supporting the vacuum cleaner structure, and a vacuum cleaner vacuum motor driven by the electric motor, and a timer unit for setting the time of beginning and ending period of vacuuming, adapted to move randomly across a carpet and to change direction of movement whenever an obstacle is encountered.