Let me start by saying I like this charger and I wish there were more 2 slot chargers with this feature set.
However, you would be remiss not to mention how LOUD the fan is. It only turns on during the discharge portion of the capacity test (GOOD) and keeps the unit quite cool (GOOD) but I literally cannot be in the same room as this charger while it is doing the discharge test.
Also, it took me several attempts to figure out what the manual meant when describing how to start the capacity test. You hold SLOT till the 4 digit capacity starts blinking then press mode once. I was expecting the 3 arrows to come up after step 1 but they only actually appear once you get it into the correct mode.
Lol i think the fan sounds cool like a little jet engine lol. I dont mind it i have a louder fan in the room where i charge cells so its not to bad. I should say for me personally. I will pull this apart and see if we need the fan when i get a chance.
Maybe we can replace it.
What termination current you see, when charge Li-Ion 18650 ?
I see on my C2-4000 termination current <0.01A, and final part of charging require additional 30-60mins, with currents of 0.05-0.01A, but this part adds <0.5% of capacity.
The C2-4000 has become my every-day charger. I like it very much. My only complaint is that its too easy to forget when its in the charging mode. Once the display dims down after a couple minutes,it kinda disappears on my desktop. Wish it had even a single led to indicate that its in operation.
Ditto most of the comments as well. The fan’s noise startled me at first until I realized it was only during the optional drain cycle which I seldom use so it doesn’t really disturb me.
The taper charge at the end does take a while but when I’m in a hurry I just pull off the cells at 98% to save time, but mostly I just drop cells in and forget.
The wallwart’s large but I think it’s helpful in transferring some of the heat away from the body of the charger itself.
I am really liking my C2-4000 and even prefer it over my 4-slot Nitecore.
What cells? Are they older cells? Older cells always take longer to terminate.
I should say cells that have aged bad my LG HG2 are not that old but have been driven hard there whole life and take longer to charge then my other cells.
A termination current of under 100ma is good for a 18650 some where around 30-50ma termination is what you are aiming for.
I’ve found that my C-2 4000 charges all button top batteries at a very low rate when on auto. Probably because it also reads all button tops as having high internal resistance—even new batteries. I’m assuming it’s because—unlike flat tops—the button tops only make contact with one of the little dimples on the C-2’s positive post. That’s my theory anyway.
Be thankful if it ends at a “very low rate “ , probably at 10% of the charging rate, for it means it’s doing what a proper cc/cv procedure charger should do.
Once the charger shows 4.20v, (the cc stage), the cv stage takes over, the 4.20v stays, but the current tapers down to 10% of the rate used in the cv until its terminated, then displays “full”.
I did a little experimenting last night with a new ncr18650ga . I first put it in slot 1. It first read very high resistance so I put it in slot 2 and the resistance went down to 110mohm,92,4.2v,.56amp. I tried it back in slot 1. The resistance read 124 mohm,95,4.2v and .09 amp. It took over 2 hours to complete charging. Does that seem like a long time or is that normal?
Yes . Seems long,right? Always get high resistance readings /low auto charge currents. Re inserting them helps reduce resistance reading usually.I think I have to override the auto select feature to get shorter times. I wish I had some unprotected cells to test.
Very long. Battery is practically charged anyway. Just use it as is all you will gain is a few mah anyway.
How long does it take if the battery is fully depleted?
Sounds like the charger is trying to squeeze every last electron it can in to the cell.
“Table 2: Typical charge characteristics of lithium-ion. Adding full saturation at the set voltage boosts the capacity by about 10 percent but adds stress due to high voltage.”
Might be better for the cell if it was pulled a little earlier in the CV stage.
Maybe the charging screen is lazy? I guess this could be resistor feedback of some sort?
It happen on my Liitokala engineer 500 it will say like 99% or 4.20v for ages and if i nudge the cell it will complete the cycle?
When i nudge it i wake it up
I agree that the end cycle is to slow on your charger mate. What is causing i am not sure it has to be a feedback problem or a wrong equation with the computer. Unless the charger is trickle feeding the cells to keep them full and that is not completing the cycle?
