how to charge a 12 volt lithium battery

First check what kind of lithium battery you have. There are major 2 type of lithium battery in the market. 3.7v cell and 3.2v cell. And find out the full charge voltage. If the cell is 3.7v. Nomally full charge voltage is 12.6v( 3S lithium ion battery. when fully charged, each cell 4.2 volt). While if it is 3.2v cell. When it fully charged, the voltage is 3.65 volt. 12 volt lithium battery pack fully charged is 14.6 volt.( 4S 3.2 v cell). Make sure your charger voltage is compatable with the 12v lithium battery.

Please note that not all Li-ion batteries charge to the voltage threshold of 4.20V/cell. Lithium iron phosphate typically charges to the cut-off voltage of 3.65V/cell and lithium-titanate to 2.85V/cell. Some Energy Cells may accept 4.30V/cell and higher. It is important to observe these voltage limits.

Important to Lithium battery chargers

Lithium cells (18650, lipos, LiFePo4 etc.) which require the charging cycle CC-CV (constant current, constant voltage). The battery system may work for other types for batteries as well, as long as they wants to be charged with CCCV.

CC-CV varies the voltage to constantly deliver the current set by you. When the voltage reaches the battery’s maximum charge voltage, the current is gradually decreased so that the voltage does not exceed the set value.