In recent years, electric vehicles have generally used the so-called three-stage charger. The first stage is called the constant current stage, the second stage is called the constant voltage stage, and the third stage is called the trickle stage. For the battery from the perspective of electronic technology: the first stage is called the charging current limit stage, the second stage is called the high constant voltage stage, and the third stage is called the low constant voltage stage. When the second stage and the third stage are switched, the panel indicator will change accordingly. Most chargers are red in the first and second stages, and turn green in the third stage. The conversion between the second stage and the third stage is determined by the charging current.
Electric car charger
Electric car charger
More than a certain current enters the first and second stage, and less than a certain current enters the third stage. This current is called conversion current, also called turning current.
Early chargers, including those used for brand-name cars, have changed their lights, but they are actually constant-voltage and current-limiting chargers, not three-stage chargers. Generally, this type has a stable voltage value, about 44.2V, which is also suitable for the high specific gravity sulfuric acid battery at that time.