Voltage of equalizing charge control point: after direct charge, the battery will generally be left for a period of time by the charge discharge controller to let its voltage fall naturally. When it falls to the "recovery voltage" value, it will enter the equalizing charge state. Why should we design an even charge? That is, after direct charging, there may be individual batteries "lagging behind" (the terminal voltage is relatively low). In order to pull these individual molecules back and make the terminal voltage of all batteries uniform and consistent, it is necessary to recharge them with high voltage and moderate current for a short time. It can be seen that the so-called equalizing charging is also called "equalizing charging". The average charging time should not be too long, generally from a few minutes to more than ten minutes. If the time is set too long, it will be harmful. For a small system with one or two batteries, even charging is of little significance. Therefore, the street lamp controller generally does not set equal charge, only two stages.