Which 18650 chargers can show cell capacity and resistance?

I pull most of my 18650 cells from old laptop batteries and I'd like to get a charger that can show cell capacity, resistance/impedance, to give me a better idea of the cells condition than the thumbsucking I do currently.

So far I have found an Opus BT - C3100 V2.2 Smart Battery Charger that seems it can do all that, currently $30 at Gearbest, which is a very decent price:

http://www.gearbest.com/chargers/pp_174044.html

The Opus has some very handy features if you are pulling old 18650 cells:

  • CHARGE: Charge battery with 200 to 1000 (2000) mA.
  • DISCHARGE: Discharge battery with 200 to 1000 mA.
  • DISCHARGE REFRESH: Discharge and charge the battery 3 times.
  • CHARGE TEST: Charge, discharge and charge the battery, show how much current was discharged.
  • QUICK TEST: Measure the internal resistance of the battery.

What is the Opus charger like and is there any other chargers that can do what I require and may be better than the Opus and around the same price?

Liitokala li500 is dirt cheap, ~$16 if you have an adapter
I think the internal resistance measuring is not the best so I push cells 5 times so they disconnect and take the lowest.

Opus does it for me.

Very decent looking charger, where can you get them for $16?

Gearbest has them for $20 at the moment with no power supply:

http://www.gearbest.com/chargers/pp_228909.html

I'm assuming the input is quite flexible if it can be powered from a cigarette lighter, probably be able to run off a 14v power supply?

Here are reviews for the two mentioned chargers:

Looking at the reviews, the IR function on the Liitokala just doesn’t work, while on the Opus it does appear to work. I think I’ve read the Opus capacity measurements are higher than actual, by a fixed fraction I presume, so keep that in mind. The Opus uses PWM to regulate charge and discharge current, with quite high pulses of ~2.5A. I imagine this can’t be good for charging some cells, but I could be wrong. Edit: it’s probably fine: Best bang for the buck charger? Anything on the horizon? - #26 by Speed4goal

Thanks EasyB

What is the difference between the Opus BT-C3400 and OPUS BT-C3100 v2.2, seems they are identical despite having different names?

Part of your answer in the thread below!

Actually that compares to the 2.1. I have the 2.2 version and I think they made the fan quieter ,not sure of the other changes!

HKJ did not review the 2.2 version. I am sure others have.

EDIT: The thread I provided goes over my failed power supply for the 2.2 and the solution. This is covered in the last 2 weeks or so of the thread. Starting @ post #128.

If you are tearing down packs more than one charger might be good, maybe one of each.

Cheap price on the 500 is directly from the company on Ali, mine was $14.12 shipped with no ps.

I have had 3x Lii500. The IR in every one of them is useless. Otherwise a good charger. I use it often.
My Opus is a tad rough and variable for IR but serviceable. There is speculation that the pulse charging is not as good for cells, especially small ones. So far…no proof of that. My oldest and best charger uses pulse charging and I have cells over 10 years old still serviceable. The Opus is my most valuable charger.

There are extensive threads on both chargers with lots of opinions on both. HJK has reviews on both (see links above post).
Others that may be more accurate are 3-4x the price.
If IR is an important feature and you don’t want to spend like $90, the Opus is your only choice I know of. You can do IR without a charger but that’s another discussion.

Do you perhaps have a link for the the ones you are referring to on Ali please?

Often a bloody mine field finding stuff on those sites!

https://www.aliexpress.com/item/Liitokala-lii-500-LCD-3-7V-1-2V-AA-AAA-18650-26650-16340-14500-10440-18500/32792032580.html

Thanks for the link, good price, worth getting a few for charging big batches.