Test/review of Charger Miboxer C4-12

Same here, that’s why I ordered the C4-12 after reading HKJ’s review. I’ve been very impressed with the C2-6000 that I won in a giveaway, so that I also use it for 4-cell lights. But with the BLF GT due to arrive tomorrow, it will be a little tedious to charge four sets of two cells separately until I’ve received the larger model!

I don’t know how to override the automatic current. I follow the instructions, set 3A (for example), but soon it returns to his automatic value.

The override the Auto mode, long press the button, but if you’re doing this and the charger won’t obey your chosen current rate, perhaps the cell’s IR is too high for the charger to follow your Manual current selection.

If you are right then it is the Auto mode that overrides the Manual current selection! About IR, I put in a slot a Sony 18650 VTC5A with very low IR but the charger continues to ignore my manual selections. It allows me to set the value I wish but then when the current appears again it displays the prior value. I tried to increase just from 0,40 to 0,50 but it returned to 0,40. I have two of this chargers and both behave in this way.
I also watched some video review on youtube and it happens the same! The reviewer did not realized it.

When I did the review the manual selection worked perfectly.

I put some 18650 protected cells in yesterday and display was .15A, so I tried to bump it up to 1A and it would revert back to .15A. Could be that the cells were 90% when I put them in and the charger needed to slow charge the last bit, I really don't know. When I drain them down more I will be able to see if it still does that. Battery spec sheet says these NCR18650B's can charge as high as 0.7C/2A.

Time to pull the trigger on one of these.

Where’s the cheapest place to get one at the moment?

Also, I’m in Australia, do I require a cable like this to go from the power point to the power brick:

When a battery is nearly full, the charger won’t charge it at the full current (I notice on low-resistance cells like my VTC6, it can still charge at a fairly high current when the display is showing like 4.15v), but higher-resistance cells will charge at a lower charge current. I believe this is the normal correct behavior of lithium-ion battery chargers.

Yup. That’s most likely what happened.

Then also the so-called Manual Selection is Automatic! I don’t agree with this choice. There is an Automatic mode for who wishes it, but if I prefer a Manual mode I want it fully manual and not just when the charge of the battery is low and the IR is little. I have also the XTAR Dragon and the Opus 3100 vs.2 and the current I selected doesn’t change until the battery is fully charged.

Nearly all LiIon charger will reduce current when the battery i nearly full, I would give it a bad review if it did not. This can be seen on the curves in all my reviews.
The display may not show the actual current, but the selected current.

Yes, right, but as you say the display do not show any reduction of current. So the Mixboxer is the more honest charger on the market! :smiley: But often it does not respect the manually selected current also when the battery is charged at just 10% if the IR is high. Why does the hell it not let me decide? When I will need a behavior very respectful of batteries I will select the Automatic Mode.

I was just reading that charging the last 10%-20% or so of lithiums at higher amps can cause "bad things to happen". This can be interpreted many ways, but for me it suggest the battery may flame out or blow. Maybe they override our impulse to charge faster near the end purely for safety reasons only, which would be a good thing.

If you were to charge at high current toward the end of the charge cycle, you would be exceeding safe voltage levels. There is a reason why smart chargers use CC/CV charging algorithm for Li-Ion cells.

Received mine today, and as expected after using the 2-bay model for a few weeks, I’m very happy with it. I put the 30Q’s from my BLF Q8 inside, and it started charging the cells that were eighty-something % full with 2.65A.

All four batteries made good contact with the sliders - can’t remember the exact IR, but it was somewhere in the thirties. I actually found that they slid into place perfectly, unlike most chargers that I’ve tried, where I often have to move the batteries about to get them in the best position.

The build quality seems really good, as well. I wasn’t quite expecting such a brick for the power supply, but I guess it makes sense if it needs 5A from a 12V connection.

The only thing that I’d like would be a clearly visible indicator that the charging process is complete - hopefully that is something Miboxer will add to future versions.

Received mine hours ago today as well. The fast charging and possibility of charging four 26650s got me.
One problem though, I have a couple of older 26650 flat top Liitokala’s I was hoping to test out, but they won’t charge at all. The charger won’t recognize the batteries.
It recognizes my 18650s fine (a NCR18650B and some 35Es), but will do nothing with the 26650s.
Can someone help me out?


Ooh, I was thinking about doing that but didn’t want to break anything. How’d you manage to do that? Pliers?

Yeah, you’re right, I just squeezed my finger between the bottom of the charger and negative tab and it does bend toward the battery and when it makes contact, charging does work.

I used pliers and held the base down with the square end of a 1/4" socket extension bar. It bends fairly easy.

I have exactly the same INR26650-50A cyan (although mine doesn’t indicate “Liitokala).

The INR26650-50A contacts does not touch the charger’s slider + or - contacts, you’ll need to carefully adjust the INR26650-50A at a slight angle until it touches the charger (forgot if it’s slanted towards the front or back, but try them).

Dunno if it’s too safe or not, but I took what klrman said about the wrapping blocking contact and just shaved off the wrapping on the negative side of the battery. Worked like a charm.