Abstract: An electronic adapter circuit for charging and/or recharging a battery of a first battery type utilizing a charging device for a battery of a second different battery type, may comprise: an electronic circuit for controlling the charging of the battery of the first battery type when the battery of the first type is charged by the battery charging device, wherein the electronic circuit has high conductivity when the battery of the first type provides electrical power to a load, and has a reduced conductivity for limiting charging of the battery of the first type when it is charged by the battery charging device. The electronic circuit may include a controllable conductivity device having high conductivity when the battery of the first type provides power to a load, and a battery charging control circuit for reducing the conductivity of the controllable conductivity device for limiting the charging of the battery.

Abstract: An adapter for replacing an original battery, light or battery powered device utilizing a battery of a first type with a replacement battery light or battery powered device utilizing a battery of a second and different type may comprise first terminals configured similarly to terminals of an original battery, light or battery powered device, second terminals for connecting to a replacement battery, light or battery powered device, and an electronic circuit for controlling charging of the battery of the replacement battery, light or battery powered device connected to the second terminals when a battery charging device for a battery of the first type is connected to the first terminals.

Abstract: An adapter for replacing an original battery, light or battery powered device utilizing a battery of a first type with a replacement battery light or battery powered device utilizing a battery of a second and different type may comprise first terminals configured similarly to terminals of an original battery, light or battery powered device, second terminals for connecting to a replacement battery, light or battery powered device, and an electronic circuit for controlling charging of the battery of the replacement battery, light or battery powered device connected to the second terminals when a battery charging device for a battery of the first type is connected to the first terminals.

Abstract: A battery operated rechargeable portable light may comprise: a light housing, a light source for producing light, a switch for selectively energizing the light source, charging contacts for receiving a DC voltage from a DC voltage source; and a DC charging circuit for coupling the DC voltage to a rechargeable battery. The DC charging circuit may apply a DC voltage of the given polarity to the rechargeable battery irrespective of the polarity of the DC voltage or the light may provide an indication of the presence and absence of the DC voltage, or both, e.g., by the light source producing light.

Abstract: An electronic circuit comprises a switching voltage boosting circuit and a current regulating circuit for controlling current flowing through a solid state light source. A control circuit controls the current regulating circuit and the switching voltage boosting circuit to control the magnitude of current flowing through the solid state light source. An error signal produced by the control circuit for controlling the current flowing through the solid state light source may further control the switching voltage boosting circuit.

Abstract: In a battery-operated apparatus comprising a load, a battery and a switch in circuit for selectively energizing the load: a comparator compares a potential produced by the battery and a reference potential for de-energizing the load when the battery potential is below a predetermined potential.