newhand
Member level 1
As we know,there are 3 phases of charging the Li-ion battery,
which is precharge,constant-current,constant-voltage.
I have some difficulty understanding the constant-voltage phase.
For example,if we want to charge 1 pack li-ion 4.2v battery, 500ma current is used in the constant-current phase,after the voltage of the battery rise to 4.2v,in the
constant-voltage phase,the voltage of the battery keeps 4.2v,the current decrease gradually from 500ma to the point that the battery can tape off.
My question is why the battery's voltage can keep constant when there is still
constant current charging the battery and if I want to design such a circuit,
what should I do to realize the constant-voltage phase.
ps:Attachment is the figure of 3 phase of Li- ion battery chargeing
which is precharge,constant-current,constant-voltage.
I have some difficulty understanding the constant-voltage phase.
For example,if we want to charge 1 pack li-ion 4.2v battery, 500ma current is used in the constant-current phase,after the voltage of the battery rise to 4.2v,in the
constant-voltage phase,the voltage of the battery keeps 4.2v,the current decrease gradually from 500ma to the point that the battery can tape off.
My question is why the battery's voltage can keep constant when there is still
constant current charging the battery and if I want to design such a circuit,
what should I do to realize the constant-voltage phase.
ps:Attachment is the figure of 3 phase of Li- ion battery chargeing