bean123
Newbie level 5
charging lithium ion battery
Hi,
My battery charging circuit has only constant Current, no constant Voltage method,
and the constant current is 1A.
When the battery voltage arrive the cutting voltage 4.2V, the circuit cut off, but the battery voltage descent from 4.2V to 4.11V within about 4 minute.
So the battery can't reach the voltage (4.2V) I want to get.
And when the constant Current is smaller, the battery voltage is higher. For instance, when the constant current is 400mA, the V gets about 4.16V.
How can I make the Voltage arrive 4.2V?
Someone tell me that the li-ion battery has a long chemical response time. and this is the reason.
Is that right?
And please give me the solution.
I need to design the constant voltage charging???
Thanks
Hi,
My battery charging circuit has only constant Current, no constant Voltage method,
and the constant current is 1A.
When the battery voltage arrive the cutting voltage 4.2V, the circuit cut off, but the battery voltage descent from 4.2V to 4.11V within about 4 minute.
So the battery can't reach the voltage (4.2V) I want to get.
And when the constant Current is smaller, the battery voltage is higher. For instance, when the constant current is 400mA, the V gets about 4.16V.
How can I make the Voltage arrive 4.2V?
Someone tell me that the li-ion battery has a long chemical response time. and this is the reason.
Is that right?
And please give me the solution.
I need to design the constant voltage charging???
Thanks