A wrist carried instrument includes a rechargeable electric energy source for providing power to the instrument. The energy source is recharged by a pair of generators, both operatively coupled to the source and generating complementary recharging currents from different physical phenomena. The first generator may be a photo-electric cell generating a recharging current in light such as exists from the sun in summer, while the second generator may be a thermoelectric element generating a recharging current from a temperature gradient such as exists in the dark or winter.

A pair of batteries of equal voltage rating are connected together in parallel through isolation diodes and in series through a first silicon controlled rectifier, the gate electrode of which is connected to the positive terminal of the first battery through a second silicon controlled rectifier and the emitter-collector switch circuit of a switching transistor. The gate electrode of the second silicon controlled rectifier is connected to said positive terminal through a capacitor and said transistor switch. The base-emitter switch actuator circuit of the switching transistor is connected across the first battery in a manner to maintain the transistor normally activated, whereby the impulse generated from the instantaneous voltage drop across said first battery, upon energization of an electric load connected thereto, is applied through said transistor switch to the gate electrode of the second silicon controlled rectifier, activating the latter to supply power to the gate electrode of the first silicon controlled rectifier, thereby turning the latter on and connecting the pair of batteries together in series. Conductors connected across the first silicon controlled rectifier are arranged for connection to the output terminals of a conventional battery charging source, rated for charging one of the pair of batteries, the isolation diodes maintaining the batteries in parallel during charging.

An electrochemical charge-storage system for defibrillator energy delivery where a plurality of switched battery cells with high energy storage capacity are incorporated for delivering an electrical charge within an implanted defibrillator system. Alternative embodiments include circuitry for battery replacement switching of a faulty battery.

An information handling system is described having a power supply (16) having a switching circuit (24) that switches a plurality of energy sources (20) and (22) between series and parallel couplings. Associated with the switching circuit (24) is a voltage level detecting circuit (18) for monitoring the voltage level of the energy sources (20) and (22). A processor (12) for controlling the information handling system (10) responds to the voltage level detecting circuit (18) and in the event of a low voltage condition, the processor (12) activates the switching circuit (24) to switch the energy sources (20) and (22) from a series to a parallel coupling. Alternatively, processor (12) responds to other inputs or conditions for actuating switching circuit (24).

A circuit for supplying energy from a battery to the load of an energy-using device is provided wherein the circuit provides for notification to the operator of the device that the remaining energy of the battery is low. The notification is provided at a time when sufficient energy remains in the battery for the operator to perform certain essential tasks. The circuit includes a battery having a plurality of cells connected in series, a first portion of which have a higher deliverable energy capacity than a second portion of the plurality of cells. The circuit further provides for sensing a characteristic of the battery indication of the remaining deliverable energy capacity lower deliverable capacity cell portion and for switching the circuit from a first mode of operation wherein energy is delivered to the load from all of the cells in the plurality to a second mode of operation wherein the energy is delivered to the load from only the higher capacity portion of cells. Switching is accomplished in response to the sensed characteristic indicating a low level of remaining deliverable energy capacity in the battery. Energy delivered to the load in the second mode of operation may be used by the operator to perform certain essential tasks before the device becomes inoperable for lack of energy.