The difference between constant current charging and constant voltage current limiting charging

 The difference between constant current charging and constant voltage current limiting charging

1. The principle of constant voltage and current limiting charging and the current calculation method

Constant voltage and current limited charging is a way of charging by regulating the voltage and limiting the charging current. When the battery voltage is insufficient, the charger charges with constant current to achieve a fast charging effect; when the battery voltage reaches the set value, the charger automatically adjusts to constant voltage to keep the battery voltage from exceeding the set value. At this time, the charger will limit the charging current to avoid overcharging. Therefore, constant voltage and current-limiting chargers need a calculation formula to calculate the relationship between the charger input voltage and the required output current.

Calculated as follows:

Charging current I = rated output current of the charger * rated capacity of the battery / remaining capacity of the battery

For example, if the charger's rated output current is 2A, the battery's total capacity is 3000mAh, and the current battery power is 20% (that is, the remaining capacity is 600mAh), the required charging current is:

I = 2A * 3000mAh / 600mAh = 10A

Note that the charger's output current must be greater than the required charging current to ensure that the battery can be charged quickly.

2. The difference between constant current charging and constant voltage current limiting charging

Constant current charging and constant voltage current limited charging are common charging methods. Constant current charging is to charge at a constant current at the beginning of charging to achieve a fast charging effect. It does not enter the constant voltage charging stage until the battery voltage reaches a specified voltage. Compared with constant voltage and current limited charging, constant current charging charges faster, but it can easily lead to battery overcharging.

Constant voltage and current limited charging charges by regulating the voltage and limiting the charging current. Compared with constant current charging, it maintains battery voltage stability and avoids overcharging by automatically adjusting charging voltage and current. Compared with constant current charging, constant voltage current-limiting chargers have lower charging efficiency but longer battery life.

In short, the two methods of constant current charging and constant voltage current-limited charging have their own advantages and disadvantages. Which method to choose should depend on the type of rechargeable battery required and the charging requirements.