| 摘要 |
1476259 Battery state of charge monitoring JUNGFER [trading as AKKUMULATORENFABRIK DR LEOPOLD JUNGFER] 3 Jan 1975 [11 Jan 1974] 256/75 Heading G1U The number of ampere-hours instantaneously available from a battery 1, Fig. 3, under test is ascertained by subtracting a first signal 25 representing the net ampere-hours taken from the battery - this signal being produced conventionally by a forward/backward counter 11 driven by an oscillator 5 at a frequency proportional to the battery current - from a second signal 22 representing the total ampere-hours available from a fully charged battery at the temperature and discharge rate of the battery under test - this signal being produced by a device 18, no details given, which itself receives signals 19, 20 representing the battery current and temperature respectively. The reason for the invention is that although a battery may be charged so that it is nominally storing H amperehours, say, the number of ampere-hours that can actually be extracted from the battery depends upon both the battery temperature and the battery current. Instead of comparing the signal 22 directly with the signal 25, the signal 22, which represents the total ampere-hours that would be available from the battery, at the present temperature and current discharge level, if the battery were fully charged, can be reduced by a device 26 (no details given) by the number of ampere-hours required to perform a particular task, such as driving a starter motor, at the temperature of the battery, so that the output of the comparator represents the instantaneous number of ampere-hours available from the battery in excess of those required for the particular task. |
