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Difference between a 'CCCV' supply and just a 'CC' supply.
#1
So I have the basics of how the lithium charge profile works, but I can't quite wrap my head around this last part:

What exactly is the difference between a power supply/charger that 'switches' to CV mode and a power supply that only has CC mode but has a nominal voltage in line with the charging voltage of the battery?

I understand constant voltage should maintain voltage and allow the current to fluctuate, but would this not happen normally on any power supply as the current draw of the battery decreases?
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#2
Almost all psus have CV. Wouldnt work otherwise. But without CC you wont be able to limit current and may even Short it out. All supplies have some kind of CC but it can be in Short mode.
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#3
So, basically... If a PSU has constant current then it functions in essentially the same way as a CC/CV charger but perhaps lacking things like low current cut off and charge stage led indication?
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#4
A PSU dont have any cutoffs No.
Most normal psus for computer and other Will Go inte overcurrent and shut down IF you dont limit them
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#5
Yea what was confusing me was that many of the Mean Well power supplies say "constant current, programmable voltage" but their chargers say "constant current, constant voltage". But I guess it just refers to their charge 'profiles'.
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#6
(06-20-2020, 09:10 PM)Shorty Wrote: Yea what was confusing me was that many of the Mean Well power supplies say "constant current, programmable voltage" but their chargers say "constant current, constant voltage". But I guess it just refers to their charge 'profiles'.

The "programmable voltage" bit means "constant voltage that you can select", so that's a good answer.
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#7
Meanwell have adjustable voltage as Said. Within a certain range bad they have. Max current aka CC.
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#8
This is the PSU I'm looking at:

https://www.meanwell.com/webapp/product/...od=RSP-750

Output voltage programmable by pot or external voltage and constant current also programmable by external voltage.

Then I would rely on the BMS to cut the charge once it reaches the low current cut off.
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#9
The bms does not cut on low current. If you plan that as a Charger you need to build that Logic your self. The bms only protects.


Note that you can have that running 24/7 IF you want towards lithium as Long as top voltage per cell is below max. The lithium battery Will raise in voltage so in end the current is 0. As Long as you dont have self dischargers that is.
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#10
Note that you only can vary voltage a tiny bit.
Als note that they have No current controll
They Will supply all they can and then go into over current protection.
Without extra electronics they Arent made to work as battery Charger.....
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