Here is a general overview of how the voltage and current change during the charging process of lithium-ion batteries: Voltage Rise and Current Decrease: When you start charging a lithium-ion battery, the voltage initially rises slowly, and the charging current gradually decreases. This initial phase is characterized by a gentle voltage increase.
Going below this voltage can damage the battery. Charging Stages: Lithium-ion battery charging involves four stages: trickle charging (low-voltage pre-charging), constant current charging, constant voltage charging, and charging termination. Charging Current: This parameter represents the current delivered to the battery during charging.
Charging properly a lithium-ion battery requires 2 steps: Constant Current (CC) followed by Constant Voltage (CV) charging. A CC charge is first applied to bring the voltage up to the end-of-charge voltage level. You might even decide to reduce the target voltage to preserve the electrode.
This initial phase is characterized by a gentle voltage increase. Steady Voltage and Declining Current: As the battery charges, it reaches a point where its voltage levels off at approximately 4.2V (for many lithium-ion batteries). At this stage, the battery voltage remains relatively constant, while the charging current continues to decrease.
When designing a single-cell Lithium-Ion charger, record the allowed maximum charge current and voltage of the battery in use. Then determine the voltage and maximum charge current of the power supply you want to use for charging. Usually, this will be five volts and between 500 mA and 900 mA (USB 2.0 and USB 3.0).
Several crucial parameters are involved in lithium-ion battery charging: Charging Voltage: This is the voltage applied to the battery during the charging process. For lithium-ion batteries, the charging voltage typically peaks at around 4.2V.