Test/review of Charger Miboxer C4-12

Thank you for your hard work, nice review.

Alright, more reading and checking member thoughts, HKJ's, testing helps.

I ordered one.

HKJ, thanks for your time in testing.

Thanks for the review HKJ.
I’m running out of space to store all these chargers I hardly use

FYI, when charging 4x Samsung 30Q at 3A on mine, after about 20 minutes of charging, cell temps reached 52C (as indicated by the charger’s own display) at which point the charger rebooted itself.

Alas, I seem to be the only one experiencing this behavior.

HKJ, excellent review as usual. What is your opinion on this charger versus the Opus BT-C3100 v2.2? Does the C4-12 pulse charge like the Opus BT-C3100?

+1

I like this charger, except the automatic current selection (Luckily it is easy to override).
It do not use pwm, but real current regulation.

I got my C4 12 2 weeks ago. I charged 4 30Qs at 3 amps without problems. One cell got as high as 57c but cooled down as the charger reduced current at 4.2v.

HKJ, thanks for another great review. Just ordered the C4-12. I just want to charge 4 x 26650 or 4 x 18650, all protected cells, so would you recommend just manually setting it to 1.0A for safety? I'm tired of 0.5A from my Xtar VC4.

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.