| 摘要 |
<p>1,157,130. Charging and discharging systems for batteries. SONOTONE CORP. 9 Jan., 1967 [14 Feb., 1966], No. 1177/67. Heading H2H. A battery 10 of sealed nickel cadmium cells is charged from a constant current source 20 using the control circuit shown in the Figure, the battery being in series with an electrochemical coulometer cell 50 of known type which manifests a sharp voltage change at a predetermined charge input to the battery, to provide a signal which is used to reduce the charging current supplied to the battery. Initially transistors 30, 40 are respectively conducting and cut-off, with transistor 70 acting as a forward-biased diode, so that a high charging current flows. When the voltage of cell 50 suddenly rises, transistor 30 is cut-offandtransistor 40 becomes conductive to insert resistor 35 in series with the battery and so reduce the charging current to a trickle value, the leakage current through transistor 30 to the cell 50 being sufficient to maintain members 50, 30, 40 in their "operated" conditions. Since the cell 50 is reversible in operation, it may be used to limit the discharge of the battery through a load 100 to a predetermined value, the load circuit being made by changeover of switches S1A, S1B. Initially, transistor 70 is conductive due to the respective high and low potentials of the cell 10-1 and the cell 50, a resistor 64 being included with cells 10-1, 50 in the transistor base current circuit. The potentials of cells 10-1, 50 are in opposition, so that when a predetermined discharge has been reached corresponding to increase of the cell 50 and decrease of the cell 10-1, the transistor 70 is cut-off and the discharge is terminated. Typical characteristics for the battery 10 and cell 50 are discussed, Figs. 1 and 5 (not shown).</p> |
