Quick question about CC/CV charging

Fallingwater

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While charging a LiIon cell at the recommended current (0.7C for most types of standard LiIon), how much charge would be in the cell (in percentage) if I stopped the charge right when the charger switches from CC to CV? I've googled but I can't find this particular tidbit of information.
 

tatasal

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While charging a LiIon cell at the recommended current (0.7C for most types of standard LiIon), how much charge would be in the cell (in percentage) if I stopped the charge right when the charger switches from CC to CV? I've googled but I can't find this particular tidbit of information.

If I remember it right, I think the display in my hobby charger indicates 4.19-4.20V before the current that was set gradually decreases to .00A for termination.
 

samgab

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It varies a bit from cell to cell, but I find it can be about 80% SOC.

Eg in this example, from a Panasonic datasheet:
ncr18650%252520typical%252520charge%252520characteristics.GIF

(The full charge is at about 2600mAh, the change from CC to CV phase is at about 2080mAh, give or take, and this was charged at ~0.7C.)
 
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45/70

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Hi Fallingwater. It depends on what charge rate the cell is charged at, but typically, a LiCo cell's voltage when the CV stage begins, is around 4.05 Volts (cell voltage independent of the charging circuit voltage, ie. the charging circuit voltage when the CV stage begins is, ideally, 4.20 Volts, but the cell voltage when removed from the charging circuit, will be less at this point). This equates to approximately 85% charged. Cells charged at a faster rate will be less charged, and cells charged at a slower rate will more charged, at the point when the CV stage begins.

Dave
 
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