Correct Charging Method for New Electric Vehicle Batteries

Many users may not be aware of the correct charging method for new electric vehicle batteries. Let’s take a look at how to do it:

Connect the positive terminal of the battery to the positive terminal of the power source, and the negative terminal of the battery to the negative terminal of the power source.

The initial charging process is divided into two stages: First, charge with the initial charging current until the electrolyte starts to release bubbles and the voltage of each cell reaches 2.3–2.4V. Then, reduce the current to half of the initial charging current and continue charging until the electrolyte releases intense bubbles. Continue until both the voltage and the current remain stable for 3 hours. The total charging time is approximately 45–65 hours.

During the charging process, the temperature of the electrolyte should be monitored frequently. Use methods like halving the current, stopping the charge, or cooling to keep the temperature between 35–40°C. After the initial charging is completed, if the electrolyte specific gravity does not meet the required standards, adjust it with distilled water or electrolyte with a specific gravity of 1.4. After the adjustment, continue charging for 2 more hours until the specific gravity meets the specified requirements.

After the first charge of the new battery, the capacity may not reach its rated value, and a discharge cycle should be performed. Discharge at a rate of 20 hours (discharge with 1/20 of the rated capacity current until the voltage of each cell drops to 1.75V), and then replenish with charging current until full. If the capacity is still lower than 90% of the rated capacity after one charge-discharge cycle, perform another charge-discharge cycle.