Advice on today’s “best” charger.

I understand that. Just making sure the poster does also.

true but the OP is thinking of cycling his batteries, the way we used to cycle our NiCad batteries.

That strategy does not apply to LiIon
it is not good to deep cycle them

These Miboxers don’t have discharge test function. The VC4S does.

Btw, anyone here have the Nitecore UMS-2? I like the size and display, but I find it behaves… erratically. Mine didn’t come with a Micro USB cord, so I’ve used a few. I’m wondering if its very sensitive to the cord and the AC to USB adapter? By erratic, I mean the buttons to view stats and switch view between cells 1 & 2 often become unresponsive. I have to unplug and plug back in again to get momentary function, then it happens again. VERY annoying.

I have found a HUGE difference in USB cords. MOST of the cords that come with cheap products are……lousy. High resistance, fiddly fit and connection. Got a UM24C USB tester + load module, tested all I had and threw hoards away.

Had an old Samsung that was extremely USB cord sensitive. ONLY cord I found that was reliable are the Monoprice Select A>Micro series. Inexpensive, many lengths, colors, and simply work.

Assume your USB power supply is up to the requirement.

I don’t own this charger, but just reading through HKJ’s review of it, he mentions that this charger can ask for a lot of current from a USB wall adapter (up to 4A), which most wall power adapters can’t deliver, so I would make sure you have a robust USB wall power adapter that can maintain voltage at high current. He also states “The charger has some problems with a unstable power supply,” but I don’t know exactly what he means by it. Maybe ask him?

And yes, flydiver is correct that there are a lot of garbage USB cables out there with high internal resistance which will further reduce the amount of available current to your device.

I bought a Vapcell S4 Plus and so far have been happy with it. It has a minor quirk when doing a Capacity Test on NiMH batteries but the workaround is easy; it doesn’t really fully recharge them so you just have to kick off another charge cycle on them. I suggest doing your own research and reading lots of reviews. Let me know if you have any specific questions about my Vapcell.

It was my incorrect way to say what I want :slight_smile:
I don’t want to discharge batteries to 0. I want a charger with a function that could bring dead battery alive

I’ll check the table.
Thank you

In my country I can’t buy Miboxer or Opus.
Can you recommend a seller from aliexpress?

Where did you buy your charger ? :slight_smile:

If you mean cycling to improve some NiMh, that can be a useful function. It is less useful for LSD NiMh.

For Li-on cycling is not useful to improve it. It just eats up another charge cycle. It can be useful for checking capacity on occasion, and checking the state of new or old unknown cells.

For truly DEAD batteries - a ‘few’ top end chargers will try to revive a dead NiMh. Many (most?) will reject it. The most useful tool for that is an old ‘dumb’ NiXX charger that will charge anything you put in it. That will generally get it ‘going’ again, THEN you can put it back in the smart charger to finish. NOTE - every time you run a NiMh to 0 volts you are doing some damage. The damage is cumulative.

For Li-on, if it is indeed DEAD (0v) it has sustained damage and should be recycled. You may be able to revive it but it is now damaged, more dangerous, and not recommended. In general any cell that spends a lot of time below 2.2v-2.5v should be considered suspect and probably discharged and recycled.

Modify your profile so we know your country. That helps us.
I don’t use aliexpress, so no help there.

I bought mine from

mainly because I didn’t want to wait on delivery from China. It appears to be available from AliExpress.

I use a GYRFALCON All-88 8 Channel Digital Battery Charger and love it. I can have 8 batteries of all difference sizes charging. You can adjust the current (amps) and max voltage but I just stick the puppies in and wait for the lights to turn red indicating they’re done. I also like that it has no lights except when you have it charging. No need to unplug it to get rid of those annoying lights :slight_smile:

Miboxer chargers are available from AliExpress sellers, but I’m not sure if there is an official “Miboxer” store from AliExpress (eg. Xtar has an “official” Xtar AliExpress store but can’t seem to find Miboxer’s official one). Anyway, I’ve tried a few Miboxer, and have bought at least 1 Miboxer charger from an AliExpress store (which turns out to be a genuine Miboxer).

My XTAR VP4 Plus DRAGON is still going strong after many years. (It was sent for review when it was launched)

I’m not looking for official store. I just can’t find any C4 Plus on Aliexpress

Is there any significant difference/improvement between Opus BT-C3100 2.1 and the Opus BT-C3100 2.2?

So is there an 18650/21700 charger besides the MC3000 that can do 4.10V charging cutoff? I’m not talking about hobby LiPo pack chargers but ones with cylindrical cell bays.

Or is there a charger that can be modded to do so? I wish my GYR-88 could do 4.10V. I have the Opus BT-3100 (v2.1?) and AFAIK it cannot be adjusted to do 4.10V, just 4.35V and 4.2V for 18650/21700 cells. I’m not above soldering or flashing (hacked, even) firmware.


could you recommend a charger for me?
I need it for 18650, maybe 21700 in the future Li-ions. I have also bunch of LiFePo4 in my garden lights.

I was looking at Lii-500s, but it doesn’t support LiFePo4 chemistry.

Thanks in advance :slight_smile:

The Opus BT-3100/3400 chargers will do LiFePO4 cells if you drill a small over the slider switch, on the inside of the bottom cover.

Use a wooden toothpick to move it to whatever you want to charge up. This option works as a storage voltage on normal 4.2v cells.


Hmm. I’d also be interested to know if there’s one other than the MC3000 (the proposed BLF UC4 charger plans to have this feature if it pushes through). I don’t know any that can have the end-voltage be adjusted (although there may be some charger models that have a slightly less than 4.20v end-voltage cut-off, but probably due to the model not voltage-calibrated to exactly 4.20v from the factory…


You can check HKJ’s table of chargers to see which supports LiFePO4:

Several of the Liitokala USB-powered chargers support charging LiFePO4, as do some Nitecore chargers.

I would recommend the Miboxer C8 for 8-bay charger that supports LiFePO4.
The Miboxer C4-12 v2 (2-button version) also supports charging LiFePO4.

You’d hope it was less likely to nearly set you house alight as the 2.1 I had could easily of done if I wasn’t a bit more aware. That could be considered quite a significant upgrade if so.