Don’t ever think about heat dissipation with any lithium batteries. What I mean is, you should only use heat as an indicator. If you are getting any heat either charging or discharging, then you are pushing the batteries too much and should reduce the current. Pushing lithium batteries hard enough to cause heating, is very dangerous. If you get any heat when discharging a Li-ion flashlight battery and are still within the rated discharge current, then it’s most likely the battery contacts that are causing resistance and are heating up and transfering that heat into the battery.
Yea, a charging cradle with all copper contacts would be a great thing. Even more important, is that I noticed is that a flat battery contact really sucks with cylindrical batteries. With a flat battery contact, only one TINY spot will hit the battery contact at one time, as neither surface will be perfectly mated to one another. A round ring contact (with spring pressure) is much better at getting a good contact. I like using the end of a copper ring terminal, soldered to whatever contact I am using.
Any mods are going to probably be better than nothing. I don’t know about copper braid itself being the actual contact though. It might be awesome, I am just not sure, as I have no experience. I know slot cars use copper braid as their electrical contact at pretty high current.
I never got the iCharger, but at least I'm learning how to use what I got. The AC680 outputs data to a computer via a tab delimited text file. This can be imported into Excel and graphed. Excel makes getting the format for the time to work correctly, so I wasted a lot of time trying to figure it out, using formulas and macros, but I finally got it.
I'm not balance charging yet. I have a 3x18650 cradle in the mail, which is about all this charger can handle. That should save a LOT of time since right now I can barely handle 2 cells per day if I charge them full, do a discharge test, then charge them back to storage capacity.
I mentioned it in another thread, but I found some open source firmware that's supposed to add internal resistance capabilities to this type of charger, and also allows logging on the pc to be done with Logview instead of their unstable software. I'm not sure the latter is so much better since Logview is in german, and while there's an english option, there's a lot of things that aren't translated.
Then I need to see about getting those power supplies converted.
This graph is a little better, but setting up a third vertical axis in Excel is proving to be too difficult.
I’m struggling to find a good 18650 holder, one with low contact resistance. The home made one from drdanke looks nice!
Also, hobbyking just released the Turnigy reaktor for 70 bucks, which is a copy of the icharger 206B. Has anyone tried it yet?
I'm on the verge of buying that new charger. I have way too many cells for the AC680 to handle. At 1.3A charge, I can only charge about 6 cells a day. I'd be charging for weeks this way. Drdanke's cradle looks nice. If you have an i4, you attach wire to the contact points. I used solder wick. Use that to attach power and balance leads with alligator, then you'll have a nice cradle for your hobby charger, but you can take off the wiring if you want to use the i4 normally.
What about the noise? Sometimes in clones they put cheap fans.
What about the updates? Can you upgrade the firmware when ICharger releases a new version?
What are the negative points of this charger in your opinion?
Thanks a lot for your input, I’m looking at this charger to replace my Accucel 6 and there are not a lot of review of the Reaktor.
Cooling fan start working only if charger going warm. Normally in small charging or discharging power fan is off.
Charger adjusting fan speed to the situation, and you can completely off fan in options.
Software is exactly the same like in icharger. I do not do any updates for now.
In my charger software version is V3.14 206B and as far as I know that is the newest software.
USB working with no problems, I tested with LabView and working good. Just select icharger 206b in charger model.
USB Driver for windows xp/2003/vista/7 is updated, and this is the link: http://www.jun-si.com/UploadFiles/USB_driver.rar
Accuracy of voltage and current is very good too, tested with good class DMM.
Charger was calibrated .
The xbox power supply is in action, and I'm finally getting around to modding this power supply too. I'm going to use servo leads to short the wires. I'll keep the fan at full speed for now. 8awg wires split and soldered into the spade connections. Later on I'll clean it up with some binding posts, and connect the power and fan wires to a pair of buttons or toggle switches. I might have some questions when I do that and get a second one to run at 24V.
The AC680 disappointed just now. It can't actually do a 2A discharge. It starts and hits 2A for a few seconds, then current drops to near zero indefinitely.
Hey leaftye, I just received an AC680 and just started using it (simple single 18650 cell setup). I've just started doing a 2A discharge test and am seeing exactly what you described above - current is high for a second or two, then drops to 0.03A! I've let it run there for awhile now and no difference. Have you figured anything out since your last post? I know you also have a different charger now, so maybe you abandoned this one.
All that’s in those lower end chargers for discharge is a resistor….which gets hot.
The AC680 is limited to 2A/10W max discharge. (The 50W type units only have 1A discharge which disappoints a lot of people)
For a single cell, fully charged 2A x 4.2W = 8.4W. It ‘should’ do it but it’s getting close to maxed out. Maybe a corner got cut here.
These units are ALL clones, and quality of components and assembly can vary. Specs unfortunately have to be taken with a grain of salt, just like capacity in batteries and lumens in lights.
Also, be sure to see if the battery can handle that level of DC. If the voltage drops (sags) too much the charger will scale back.
Thanks for the info. The cell is a Sony NOS laptop pull rated 2,450mAh (I think) and has been tested by others up to 5A discharge. Voltage held pretty well (steady) at 1.5A discharge level. Maybe chock it up to low quality components? Wonder if a resistor replacement / upgrade is all that's needed and how simple it is?
Never tried to dig that far into my own AC-6 beyond lubing the lousy fan periodically.
One thing you can try I think is opening it up and seeing if you can improve the thermal transfer from the circuit board to the case. Mine has a contact to do this and as usual had lousy thermal paste on it.
Another issue is the ‘AC’ units are the same as the DC units except they have a laptop PS imbedded. IMO this is a weak link as they get hot, are more likely to burn out, and make it harder to fix if they do so. None of these style clones are actually AC, they are all DC powered.
