New B-grade Lifepo4 cells High voltage

[Guusloman]

Hi everyone,

I'm new to this forum and fairly new in the world of lithium. I just bought four 3.2v Lifepo4 cells trying to make a 12v system for my RV. I thought I'd start of small and build a bigger system when the small one worked out. So today I was trying to manually balance the cells when I found something weird. All of the cells where around 4.4 or 4.5v. I checked the meter I was using and it said the same thing. The cells I bought are used cells. Could it be that the previous owner charged them all the way up to 4.5v? If that is the case. Could it be that the cells are damaged? Or is there something else (I'm doing) wrong?

I also ordered a small BMS, but I'll have to wait until it comes in.

These are the cells I have: https://www.alibaba.com/product-det...lithium_60696358171.html?fullFirstScreen=true

 

[Nedlyest]

Sorry I don't have an answer for your question. I have a question. How was purchasing from Alibaba? Did you need to fill out customs paper work? Was there anything 'extra' you had to do (pay fees,go to Port of entry to pick up)?

 

[Ampster]

If they are truly LFP or LiFePO4 cells the nominal voltage should be 3.2 to 3.3 resting after being charged to 3.65. They could be damaged. Check your Voltmeter agains a reliable standard like a AAA battery. What was the process that you were doing to balance them?

 

[Steve_S]

Anything above 3.65 for LFP is BAD... that is damaging the cells.
The link provided takes us to 12AH cells TWELVE AH ? those won't go far for anything.