Trickle charging Li-ion...

MrAl said:

Hi,

I think you meant to say: "It suggests a maximum discharge of 0.5C but this only allows 95% charge capacity..."
but i see them going up to 2C on that.
Although it does suggest a max charge rate of 0.5C too, but no data on how that limits the apparent capacity.

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If you research further on Li-Ion the charge rate affects final capacity considerably, with 0.2C charge giving 100% charge, as you go higher the capacity reduces - it's swings and roundabouts, you can have either fast charging or full capacity, you can't have both.

Nigel Goodwin said:

If you research further on Li-Ion the charge rate affects final capacity considerably, with 0.2C charge giving 100% charge, as you go higher the capacity reduces - it's swings and roundabouts, you can have either fast charging or full capacity, you can't have both.

Click to expand...

Hi,

Ok thanks.
I questioned it because that was not apparent from that data sheet.
In fact, most of the data i have seen show that charge acceptance goes up with charge current but that's for NiMH. I dont think i have yet seen data showing this for Li-ion. I would suspect that is a curve, but what shape i cant say yet. If you have more data on this it would be good to see here.

If the battery is with a 4.2 V protection board as usual, it's OK because the latter blocks any voltage > 4.3 V (Some low quality power banks make use of this thru a 0.5 Ohm resistor to USB to charge the internal batteries).
Will degrade permanently if the battery is directly exposed to 4.5 V, the self-discharge (of low capacity such as 1 Ah) is normally < 1mA, i.e., it will be eventually charged to 4.5 V. This will DECOMPOSE the ANODE (Normally CoO2) because 4.5 V exceeds the electrode potential (ANODE minus CATHODE = CoO2 minus Li).