Review: XTAR ST2 - 4.1 Fast Battery Charger

What voltage does it switch over from the fast charge? How long does it take to get there on your 30Q for example? I see it took 56min to fully charge it, but I guess the real benefit of this charger should be how fast it can get you back to basically full and going again.

Thanks for the review!

Thank you for the review, interesting charger. I never had a Xtar device before but two cells is what I could go for.

I have not measured the voltage does it switch over from the fast charge, but I think that, looking at the test I did with the 30Q, the declared values on the charge speed are correct.

Thank you for reading it.

What adaptor would you recommend, that could be bought on BG/GB/FT?

Isn’t 4,1A charging each cell rather bad for cycle life, especially for high capacity cells?

I’m wondering that too. I’m wondering if since they are temp monitored that it may not be so bad. My other thought is, even if it is bad, how bad is it? Will I only lose 5% of my charge cycles? That may be worth it for some to be able to charge this fast.

What voltage does the charger terminate at, measured with an accurate multimeter?

It’s a little over 1( or 2C) for most of 18650s, of course the cycle life will be reduced,but not too dramatic, not all people care about that, mostly it’s the people who doesn’t store 18650s at home

A compatible PD2.0 (Power Delivery) or QC3.0 (Qualcomm’s Quick Charge 3.0) adapter.
QC3.0 is quite common and you find it without difficulty.

For me, recharging to 4.1A is to be used only if necessary.

My multimeter finally scored me 4.19V.

/\ . 4.19V…. nice. :+1:

Very good review… thank you!! :beer:

Not bad at all,very close to perfect :+1:

Great charger, but that’s a bit disappointing. For example why not 3A if the cell allows that. This way only very good cells benefit from the 4.1A. 2A charge isn’t very special.

BTW great review, it gave me a lot of info.

Do such cells fit easily in the charger? I’ve seen chargers that are 21700 compatible, but the fit is so tight a crowbar is needed to get them in their slot :slight_smile:

Last question. In my car I use a 2A 1 slot Basen charger. 26650 cells fit and charger but due to their size contact is bad. A bad road can be enough to shift the battery a tiny bit and charging stops.
So my question is: does this charger has that problem?

I’m one of those some…. but I admit putting more spare cells in my car might be the smarter option. But even then, life can be chaotic and a quick charge can be needed.

Don’t forget about 26650 cells (5200mAh). For those cells 4.1 amps is more suitable.

Another thing is that the charger picks a safe current. That means that the charger doesn’t blindly pump 4.1A into every cell. Yeah, the user can override that. Can XTAR be blamed for that?

That’s correct, but still a small warning about car chargers.

The max input of the charger is 3A @15v.

This charger is QC3/QC4 but only outputs 2A @12v. (24 watt)

So:
XTAR can handle 45 watt
Car charger maxes out at 24 watt

2 cells charging at 4.1 amps (possibly) require 34 Watt.

So… while QC3 this charger isn’t powerful enough for the XTAR.
I have charger of this brand to charge my OnePlus with Dash charge in my car. It works great until outdoor temps reach the upper 80’s then it suddenly charges much slower. Overheating I guess.
So while roma58 is 100% right QC3 chargers are easily to be found, it’s not so that all allow you to reach the full potential with the XTAR.
Just my two cents.

Perhaps you can tell if its USB C could also work for output (i.e. power bank mode)?

No, it doesn’t have that function.

Just sharing…

while charging 2x 4.1Amps

TC66C USB meter shows: