Tuesday, November 1, 2016

Selecting a Charger for Li Ion Battery

Selecting a Charger for Li Ion Battery


In this discussion we try to learn the right procedure for selecting a charger for a Li-ion battery. The question was raised by Mr. Akshay.


The Question


Hi Sir,

I have a 5000mAh Li-ion battery. Can i select a charger for my Li-ion battery having the following specifications, the product is available on ebay?

I will be thankful if you can help me with a better option or alternate options over this.

Thanks & Regards,
Akshay G. Anarse

Selecting a Charger for Li-Ion Battery

Specifications of the Li-ion Battery charger

Lithium Ion Battery/Cell Charging Module with CC-CV operating mode, high performance output.

Just because you can Charge your Li-ion battery optimally, a Li-Ion charger would need 5V mini from a PC USB source, in order to ensure a direct charging of the battery from the PC.

RED led illumination indicates charging mode, while the BLUE Led glows as soon as the battery is Full.

Module Specifications: non-isolated module with Li-ion/Li-Po protection chip.

Size: 25x19mm

Color: As shown in the ebay picture

Maximum current charging Temperature: 30 c

Input voltage: 5V via Micro usb or from any external 4.5V -5.5V DC power supply.

Output voltage for charging the battery to full level : 4.2V

Output current: 1A, and self-adjusting as per the battery mAH specs

Charging Method: CCCV (Constant Current-Constant Voltage)

Protection Chip included: S 8205A

Operating Temperature for this module is as per the Industrial grade (-10 to +85 ) 



My Reply

Hi Akshay,


Your Li-ion Battery is rated at 5000mAH, so charging it at a 1 amp rate could cause a slow charging of the battery, and could take many hours, therefore selecting the charger for your Li-ion battery is OK, but will have this drawback.


In order to charge your battery at a faster rate, a preferable rate would be 3 amp, higher charging rates up to 5 amps could be tried but that would cause some heating of the battery and therefore might demand a temperature controlled circuit.

A fan cooling could be used for keeping the heat of the battery under control so that the battery is able to charge quickly at a 1C rate.

Here "C" refers to the AH rating of the battery, therefore 1C signifies charging of the Li-ion at its full 5 amp rate.


Instead of going through the hassles of selecting a charger for a Li-ion battery from the market the unit could be built and used at home by following the instructions as explained in this Li-ion battery charger circuit with auto cut off


Available link for download