CC-CV Charge Profile (Constant Current - Constant Voltage)
The two-stage charging method for lithium cells. First the cell voltage is raised up to 4.2 V at constant current, then the voltage is held constant at 4.2 V while the current is allowed to fall by itself. When the current has dropped to about 0.05 C the charge is considered complete.
In the first stage (CC) the charger holds the current constant; the cell voltage rises in a near-linear fashion. When the cell reaches 4.2 V the second stage (CV) begins: the voltage is now constant and, as the cell fills, the current it draws decreases. When the current falls to the order of 0.05 C the charge is terminated.
- Why two stages: constant current on its own drives the cell into overvoltage; constant voltage on its own draws far too much current at the start. The sequence of the two provides both speed and safety.
- Perception of fullness: the CV stage takes a significant part of the total time and fills the last 10-20% of the capacity. It is normal for a unit that looks almost full to keep sitting on charge.
- Rule: never feed a lithium cell from an unidentified adapter; the charge control must monitor the cell voltage and temperature.
On ST series remote controls the charging input is the AXI-Link 3-pin industrial connector; use the unit supplied with the product for charging.
The context in which this term is used: Wireless Crane Remote Control Selection Guide