Charging Li ions to 3.6v using LiFePO4 setting

canonite

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Thought I came across a post which mentioned that in order to store cells, we should keep the optimal voltage to about 3.6~3.8v using LiFePO4 setting..

For the life of me, I can't seem to locate that post using the CPF app..

So, to clarify and ensure my house my house remains intact, ... I'd like to confirm...

Li Ion has few types of chemistries .. Most of which can attain 4.2v properly charged. For LiFePO4, the voltage goes up to 3.5/3.6v charged .

If the charger (eg D4, VP2) supports LiFePO4 , could the setting be used to charge a normal Li ion battery, so that the cutoff is around 3.6v, for storage?
 
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Gauss163

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Typically manufacturers recommend to long-term store at about 40% capacity. It is true that for some chemistries the LiFePO4 charge termination voltage of 3.65V is about 44% capacity, but for others it is only about 5% capacity(they're 40% at 3.80V), e.g. see these graphs. So using LiFePO4 charge as a storage charge only works for some chemistries, since it would be a bad idea to store cells at 5% capacity.
 
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canonite

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Based on the table , NCR B cells @ 3.6V is about 39% and 3.7 v is 53%.. My cells are mainly Olight 3600mah, and soshine, panny green, Nitecore nl189 3400mah.. Believe all the base cells should be NCR B ...

So to confirm I understand it correctly, I can use the LiFePO4 setting, which will give me approximately 39~53% capacity ... Meaning to say that it is only a setting which set the termination voltage to 3.65v and is not something that will explode , ie charging an alkaline ...
 

Gauss163

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Yes, LiFePO4 uses the same CC,CV charging algorithm, but the termination voltage is lower, 3.65V vs. 4.20V (or 4.35V). There are no safety issues posed by undercharging Li-ion, only with overcharging.

Beware that because LiFepO4 are more tolerant of abuse, some fancy chargers may have implemented special algorithms that exploit this, e.g. to charge them faster. But it is highly unlikely that anything like that will occur in consumr-level single-cell chargers. As long as you have the ability to control the charge current then all should be well.
 
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canonite

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Thank you for the explanations! Just got into this hobby .. Playing it safe by getting protected cells and reading as I go .. Only thing is that, the electrical parts are too technical for me

I went round looking at hobby chargers.. Not too cheap over on this side of the pond ... Don't intend to invest in one since I am not into the RC hobby yet...
 
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