The 12 in the C4-12 is 12A spread across 4 slots. Capable of 3A each slot
Definitely the SkyRC MC3000 if you want more analysis on the batteries you’re doing testing of.
Since capacity test and IR test is a requirement, then I’ll suggest these:
- Opus BT-C3100 (try not to do discharge testing at 1A since the unit will heat up and pause, which results in incorrect too high capacity readouts; consistent IR reading)
- ZanFlare C4 (not sure if this model is still available, the IR reading looks consistent, capacity test can read a bit higher — but if you’re comparing with this same charger it’s OK)
For general purpose charging of many batteries, I like the Miboxer C8 with its 8-slots. It won’t charge too fast (like the C4-12/C4-12v2) but has IR reading and charged capacity readout; but no “analyzing/capacity-testing” function.
Thanks for explaining the differences. It’s gradually making more sense. If the main difference between the C4 and C4-12 is the charging current, I’ll probably be fine with the former as I usually plan ahead and am not in a hurry.
How do the Miboxer C4[–12] and ZanFlare C4 compare?
Miboxer (the C4): automatic charging (based on battery type, internal resistance), higher available charge current (1.5a vs 1a for all 4 slots), LiFep04 support, supports li-ion 4.3 and 4.35v. The C4-12 adds 3A across all 4 slots, but is otherwise the save as the C4.
Zanflare: analyzing function for measuring battery capacity and health (charges, discharges, recharges and measures capacity) real time battery info in all 4 slots (no need to cycle through them), really easy to use
You said you didn’t need fast charging. It’s up to you, but if those extra features on the miboxer don’t matter then get the Zanflare.
I have a noob question…please pardon my ignorance….does using a fast charger run any increased danger for batteries overheating?
I think most chargers, especially ones that charge with higher current, would have a resistance test (or temperature sensor, which is more rare) and shouldn’t charge high-resistance (old) batteries at too fast rate. Maybe the issue though is charging good batteries with small capacities (eg. AAA or 10440) at too high current, then they may heat up, but should reach the end-voltage (full-charge) faster — this may be bad for battery life cycle, but I think they won’t “overheat” enough to cause explosions or such to occur. (I might be wrong…)
However, old defective batteries (eg. Sanyo red 2200mAh 18650s from laptop-pulls) have been known to overheat dangerously (as in too hot to touch) when trying to charge them to full. It’s probably more dangerous to charge unknown-condition batteries without monitoring them…
for instance see here:
https://secondlifestorage.com/showthread.php?tid=303
I have also personally experienced the same scenario as the one posted in that thread.
Thanks, Sirstinky, that’s a nice summary.
d_t_a What do people mean by “monitoring” charging? Being in the same building? Having it in the same room and sometimes peeking at readings? Occasionally touching the batteries?
Didn’t the Miboxer advertize “intelligent” charging by varying the current according to periodic internal resistance measurements?
I don’t think anyone is sitting in the same room staring at batteries charging. I charge mine in a basement (very little flammable nearby), on a steel shelf with tiles under the charger and battery, a smoke alarm a few feet away and 2 fire extinguishers within arms reach. I often have a small cooling fan running if I’m charging a bunch or running charge/discharge cycles. I never leave the house or go to bed with Lithium charging. I have no problem leaving NiMh charge unattended. I don’t push charging, batteries seldom get more than warm, but I don’t use really slow rates either.
Batteries are watched carefully through the first charge/discharge cycle to see how they act, laptop pulls, old cells, or unknown cells especially. I will check the charger reading periodically, and test the temps by hand. If they don’t ‘behave’, they get discharged and recycled.
The lithium ion world of batteries is so different. I don’t really have fireproof areas, at least not within earshot or line of sight. With NiMh batteries my habit is to have them charge overnight which is why I don’t worry about charge rates. If one is to “watch the pot boil”, the rate becomes more significant.
Do people take the same precautions with USB charging flashlights?
Ugh…yeah, I found out about the Sanyo red laptop pulls. They got pretty toasty so I abandoned that real quick.
I have quickly collected a few lights and so my charging area is getting pretty busy. I have been thinking about wire rack shelves with laptop cooling fans mounted under to keep airflow…but was not sure if that is a moot dumb idea.
Think of the monitoring like set-and-forget, meaning you stick the battery in, regardless of what type, or age, and the charger picks the best current setting and charge profile. Charge profiles are very different for li-ion and nickle metal hydride/nicads. I don’t care for those full automatic chargers since they sometimes might not get the charge profile just right, especially if their internal resistance measurement is not accurate. A old, high resistance cell might be overcharged or charged too quickly (termination is too late and it gets too hot or under charged. If you pay attention to HJKs reviews of those chargers, you find that they don’t always get it 100% right, meaning a human with experience will be better than a programmed machine.
You don’t want to charge a AAA cell at the same current as a AA or C size. The miboxer C4+, c4-12, C2-4000, C2-6000, SkyRC MC3000, and I believe the Opus all monitor cell temperatures. I think that is mandatory for fast charging. If li-ions get over 60 or 80 C, they are either damaged permanently or suffer damage and lose capacity. Old cells are especially vulnerable to this. If you get the automatic chargers, make sure you watch what the charger sets itself at, and if you feel it’s off, change it manually. That’s why I like my Zanflare. It’s default setting is conservative enough for just about all batteries except old AAA’s.
I used miboxer c4-12. I used it so that I can control the amount of charge current. For my 21700 battery esp 4500mah vapcell, I’ll will used 800ma or 1000ma charge. Why? 1. Cell temperature stay low, low temperature is goood for cell life expetancy. It has temperature control though. 2. To maximizing cell capcity, I cant recall where. But there a different between high charge current and low charge current over the cell capacity. High chrging=capacity not fully. Lowcharging=capacity near or close full.
3.20 to 4.20v.
Sirstinky hasddie293 Yes, I would consider conservative default settings desirable.
And what? There’s a C4+ ? 
Yes. The C4+ is the latest version of the original C4. It’s been our for a couple years now. It’s basically the C4-12, but doesn’t charge at 3A on all 4 slots where the C4+ does 1.5A. It also supports li-ion high voltage cells which charge to 4.3 or 4.35v not 4.2. These are rarely encountered, but usually in laptop pulls.
I recently received the Gyrfalcon all-44 ordered from Mountain Electronics. I really like it! I can now charge my Eneloops independently rather than in pairs. It’s easy to set the charging rate. No switches to set for battery types.
Miboxer could benefit from making a comparison chart with all the C4 variants and versions…
a1penguin Thanks for mentioning the Gyrfalcon All-44. It got a good review from HKJ.