Abstract: A transformerless battery charging circuit is described including a rectifier, a semiconductor switch in series with the battery, a sensing network monitoring battery voltage, a trigger circuit responsive to the sensed battery voltage for controlling operation of the semiconductor switch, and a voltage regulator for regulating output voltage of the rectifier as supplied to the triggering and battery voltage sensing networks. The circuitry in combination with an appropriate rechargeable battery also serves as a power supply to drive a DC load connected to the battery.

Abstract: A rechargeable flashlight is disclosed having the charging unit self-contained in the flashlight housing. A rechargeable cell or cells has its opposite end surfaces making respective abutting contact with adjacent partition members extending transversely and integrally attached to the housing of the flashlight, providing immobilization of the cell(s). A standard two-cell flashlight is retrofitted to house a single rechargeable cell and self-contained tethered charger.

Abstract: A battery container, for housing as an example a 12-volt rechargeable battery of electrochemical cells, features a pair of co-fitting molded trays whose outer surfaces are formed of parallelized closely spaced elongate arches, forming a very compact container for immobilizing the cells in an integral battery assembly.

Abstract: Circuitry is provided for automatically selectively switching a load from a primary power source to a secondary power source, and back again, including switch means connected between the primary and secondary power sources, and control circuit means which controls opening and closing of the switch according to the sensed voltage level of the primary source. Once the secondary power source has been switched on, at such time as its voltage level drops below a predetermined level the switch can be adapted to automatically disconnect the secondary power source (e.g., battery) from the load.

Abstract: Electronic circuitry for charging batteries is designed to charge the cells at a relatively high charging rate through a charging path which includes a semiconductor switching means, e.g. a transistor. Control circuitry is provided including a shunting controlled rectifier which is triggered into conduction when the battery has reached its nearly fully charged condition, thus shunting current away from the battery and preferably latching the transistor into non-conduction. A lower rate, trickle maintenance charge is provided by way of a resistor shunt across the switching means. The effect of temperature on the shunt controlled rectifier gating requirements is used in a positive manner to automatically latch the transistor into non-conduction as the cell approaches its fully charged condition while simultaneously preventing overcharging by tapering the battery voltage to a suitable level.

Abstract: A battery and enclosure such as a rechargeable lantern battery housing a self-contained battery, and a recharge jack mounted in the enclosure, includes a low resistance, high power current-limiting means connected between one of the output terminals and the corresponding polarity terminal of the battery and which is provided with heat indicating means for determining if the output terminals of the battery have been short-circuited.