Circuit for providing electrical energy from a rechargeable battery to a load

A circuit for providing electrical energy from a rechargeable battery connected in use to the circuit to a load connected in use to the circuit and for controlling charging of the rechargeable battery, the circuit comprising:

• a first battery connector for electrical connection to a first terminal of a rechargeable battery connected in use to the circuit;
• a second battery connector for electrical connection to a second terminal of said rechargeable battery;
• a first load connector for electrical connection to a first terminal of a load connected in use to the circuit and to a first terminal of a source of electrical energy connected in use to the circuit;
• a second load connector for electrical connection to a second terminal of said load and to a second terminal of said source of electrical energy;
• whereby said load and said source of electrical energy are connected to the same load connectors of the circuit;
• a charger circuit for receiving electrical energy from said source of electrical energy and outputting the electrical energy to charge said rechargeable battery;
• a voltage control circuit constructed and arranged to control operation of the charger circuit by comparing a voltage difference between the first load connector and the second load connector with a threshold, wherein the voltage control circuit is constructed and arranged to control the charger circuit to operate to output electrical energy to charge said rechargeable battery if the voltage difference between the first load connector and the second load connector is greater than the threshold, and wherein the voltage control circuit is constructed and arranged to control the charger circuit not to output electrical energy to charge said rechargeable battery if the voltage difference between the first load connector and the second load connector is less than the threshold.