Need to convert to Lifepo4 chemistry

tbailey

HI I want to convert all my Li-ion/Li-PO batteries to LiFePO4.

I expect most will be the 18650 variety. I suspect that it’s not a simple replace as the charging voltage might be too high. Has anyone here been successful in doing this?

olelon david

What is your mean “charging voltage”?

You can replace them(18650 cells) one by one without having to worry about charging them ahead of time, what are your concerns about voltage and why?

tbailey

Li-ion have a higher charging voltage than lifepo4. I’m concerned that the higher charging voltage will damage the cells.

however what if I put a diode like a in4001 in the circuit to drop charging voltage by .8 v

olelon david

The internal cells of LiFePO4 have a voltage range, generally reaching up to 110% of the working voltage (nominal voltage). So don’t worry if it doesn’t exceed 110%. For example, if the nominal voltage is 3.2V, you can charge it to 3.2 * 110% = 3.52V, and so on.

As for your mention of connecting IN4001, you can try this if the charging voltage hasn’t reached 110% of the nominal voltage marked on the cell. If the charger voltage itself hasn’t reached 3.52V, you don’t need to add 3.2V either.

You can check the voltage and current conditions during charging of the LiFePO4 chemical substance. You can refer to the following pictures. Hope this helps you. If not, please let others discuss and help.