1. Determine the battery charging features, according to the choice of the type of battery testing the charging characteristics, its actual charge characteristic curve.
2. Choose charging ways, with a SCM to design in the process of charging circuit. Now on lead-acid battery charging the most commonly used has the following several ways:
(1) constant current charging mode. Advantages: early charging current is smaller than constant pressure charging current, will not cause damage to plate; Disadvantages: in the late charge because the battery has been charged, so the total energy consumption in the decomposition of water, electrolyte temperature, easy to damage the plate.
(2) constant voltage charging ways. Advantages: charging voltage constant, so in the late charge current is very small, will not harm as constant current charging battery; Faults: at the beginning of the charging for the battery voltage is very low, so the current is bigger, detracted from the battery life. (3) a three-stage charging ways. This way USES the first constant current charging, constant voltage charging again, finally USES the floating charge for maintenance. Advantages: compared with the above two ways, can greatly improve the efficiency of battery charging, shorten the charging time, and can effectively extend the life of the battery. Weakness: the long-term without batteries, new batteries, or at the beginning of the charging has been in the depth of discharge of battery, just start using quick charge will suddenly increase analysis of accumulator volume, shorten the life of the battery.
(4) four sections of the charging mode. This way is a three-stage charging ways of improvement, in the constant current charging before charging, make up the shortcoming of the three-stage charging mode. However, the above four ways of charging current is not interval has been output, cannot eliminate the phenomenon of "polarization", and "polarization" phenomenon will shorten the cycle of battery service life.
(5) pulse charging mode. Advantages: can eliminate the phenomenon of "polarization", at the same time, pulse current can be deeply to activate the battery internal active substances, greatly improve the battery charging capacity; Moreover, the way the battery plate have to strengthen its toughness effect, can significantly improve the battery service life cycle. In view of the time and its own ability, charging circuit adopts a three-stage pulse charging mode.
3. Set up the actual circuit and debug. Including charging circuit, protect circuit, display circuit, etc. System block diagram is roughly as follows:
The battery plate have to strengthen its toughness effect, can significantly improve the battery service life cycle. In view of the time and its own ability, charging circuit adopts a three-stage pulse charging mode.
