Charging 21700 battery at 2000 mAh

[Mowgli76]

Hi
I just got a xtar VC2s charger for my 21700 batteries (Samsung 40T).
Chose that charger also because it "charges at safe low current".

When it charges 2 batteries, it's at about 1000 mAh for each battery. All good.
But when charging only one battery, it charges it at 2000 mAh. Hmm?

I assume 2000 mAh is still "safe".. But won't that reduce lifespan on the battery?

The charger manual says "when the power supply is insufficient, the charger will reduce the charge current correspondingly".
So maybe I should get a usb power supply with like 1000 mAh output?

I will only be charging one battery at a time, and prefer charging slowly if that gives more safety and lifespan.

But I don't know if charging at 2000 mAh is really an issue..

 

[HigherStateD]

Which cells are you charging? What is their rated charge current and fast charge current? Most high amp cells can take higher than 2 amp, iirc, some as high as 6. That will, obviously reduce life span, but slower 2 amp would be fine.

 

[Mowgli76]

Which cells are you charging? What is their rated charge current and fast charge current?

They are Samsung 40T (21700).
I found this info. Looks like 2A is fine then?

• Standard charge: CCCV, 2A, 4.20V, 200mA cut-off
• Rated charge: CCCV, 6A, 4.20V, 100mA cut-off

 

[sonicbomb]

Batteries like to be charged slowly. Its all about time and convenience.

 

[mimöschen]

2A charging shouldn't be problematic, but to maximize a cell's cycle life it's a good bet to keep the charge current at half its standard charge rate, so you can squeeze out a few more charge cycles before you have to buy new cells.

 

[G and C]

I have the XTAR Dragon to charge all my cells with, and I've really grown to love the fact that I can set the charge rate all the way down to a half amp. My batteries get charged as slowly as possible, they seem to last longer that way.