| 摘要 |
The switch device comprises semiconductor switches such as MOSFET-switches (11) connected in parallel between the middle battery cells (7, 9). The switch or switches are generally plate-shaped and comprise each one a main part of body and have one electrical terminal located on a large bottom side and another electrical terminal located on another side of the body. The switches are mounted in a line or a row on a large side of a first electrically and thermally conducting metal plate. A second conducting plate comprises two large sides on an edge connecting the large side. The edge extends in parallel to the switches and at one side of the switches. The second plate is arranged to form a gap between the two plates which are then the electrical terminals of the switch device. Electrical connection wires extend between the terminals located at the other sides of the switches and the second plate. For providing increased heat dissipation the first plate can be prolonged by a bent cooling flange. The switches are controlled by a processor (15) which can receive signals from the exterior, such as rf signals received by a receiver (25) for allowing a high but not too high current for powering a starter motor from the battery. In other cases only small currents can be drawn from the battery for powering the charge state and can block also small currents when there is too little charge left whereby also a sufficient charge can be left for starting the motor. For an interrupt in a lead to a power supply unit the control circuit can be provided with voltage from a reduced number of battery cells. Therefore, suitably placed diodes are provided in the interior supply lines to the power supply unit. |
