I have just bought the Imax B6 and its manual doesn't explain very clear how to set it up. However, the setup menu is simple to scroll through.
My questions:
1/ The manual said the charger can take the input from 11-18V DC. I have a DC power supply of 16V , 1A and when I plugged it in, the charger displayed " Input Volt error ". I tried with another DC power supply of 13V, 1.8A and charger accepted. What wrong ?
2/ The manual said it can charge Lipo, Lion, NiMh, Nicad and Pb types but the Menu has only Lipo, NiMh, Nicad and Pb options. Should I choose Lipo option to charge my Trustfire li-on 2500 mA ?
3/ In Lipo sub-option, only 3.7V is available and ampere can vary from 0.1A to 5A. How much ampere should I choose for my li-on 2500mA ?
Different brands of hobby charger approach programming a little differently to each other, but chances are that you can either change the Li cell type in the setup menu, or having selected the available Li cell option (Li-Po in this case) and selected to charge, that within the charging options, as well as altering cell number and charge rate, you can also change the cell type.
After I fiddled around with the charger, I found out the way how it works.
Another thing I notice that the 2 new Trustfire 2500mAh out of the package, one measured 3.69V, the other 3.93V.
I charged the 3.69V @1.3A and 3.7V. After it finished charging, I measured it again and the voltage was only 3.9V, althought during the charging process the Imax showed 4.2V. Something wrong with this battery ?
The best advice I can give would be go to youtube and type in Imax b6 there are a bunch of good reviews and setups that people have posted. It's the only way I could figure it out.
Resistance of the cell will change with temperature, and the higher the current, the hotter the battery will become.
I tend not to charge over 1A unless in a real hurry. You'll get premature charge termination and not fill the battery completely. If you aren't in a hurry, lower currents generally lead to a fuller battery. Not only do you avoid heating the battery, but most hobby chargers terminate charging at 10% of the initial charge rate when they are in the constant voltage phase of the charge profile, so if you set the charger at 1.3A, the charger will terminate at 130mA, at 1A charge terminates at 100mA, while at 0.5A the charge terminates at 50mA and so on.
Getting back to the original question, the hotter the battery is while charging, the more the voltage will drop after charging as the battery cools, though admittedly, dropping to 3.9v is a bigger drop than I would expect.
If you charge the second cell under the same settings, what reading do you get from that one?
Althought I set the charger charged at 1.3A but it started with 0.7A then gradually dropped down to 0.1A. The label said it is a "professional intelligent charger"
After the first initial charge, I discharged and recharge it. The second result was better than the first charge, reading 3.99V.
The other cell is ok., charged up to 4.09V.
The charger is a copy of Imax. It shows "Sky charger" when boot up. Cost only 10$Aus and shipping costs 12.50$ !! Yeah, the postage stamp is 78 Yuan.
I don't expect them as good as a brand name for this kind of money. Will see how it performs when I do some other tests later.
Starting at a lower charge rate than you set may just mean that the battery wasn't fully discharged, and so the charger has quickly brought the cell up to 4.2v - before the current has ramped up to 1.3A - and then entered the constant voltage phase, keeping the cell at 4.2v while gradually lowering the current to stop the cell voltage increasing. It's hard to say for sure without watching what the charger is doing. If the cell were fully discharged (down to 3v) and then recharged, and the current never reached the set value, then I would have to assume that something was wrong - the charger, the cells or perhaps the power supply.
i would try using lipo mode and charging at 0.2 amp or no more then 0.5 amp, some times charging cheap cells they climb in voltage with high amp charge rates and cut out to early, i know the charger is not charging at the full 1.3 amp you set but give it ago.
even with my hobby charger i only charge my 2400 at 0.5 amp or if im in a rush 1 amp but i series balance charge muiltible batteries at once.
the imax,s can be 0.04v + out per cell ive had a couple over the years and i know some one who still uses one, his slightly over charged with the main leads end voltage always reading under what it was, where mine was always slightly under what the main charge leads said and these where claimed geniune,s.
maybe see if you can down load a manual for it if you have not got one and if you get your charger sorted
check out balance charging, its not for every one but i now balance charge 6 at a time in lipo balance mode at the same time i can charge one.
Thanks for your advise. I will discharge both Trustfire cells and recharge to see how they go. The cell is 2500mAh, so I thought charge it with 1.3A would take 2 hours and it is reasonable time to charge according to my basic electrical knowledge. Next time, I will charge them at 0.2A.
I tested the charger with 2 Nicad packs 7.4V and 9.6V. It seems ok.
0.2A is probably taking it a little too far - you'll be charging for ages. 0.5A seems like a sensible compromise. A slow charge, but not absurdly slow.
i bought an imax b6 charger and im needing to know how to hook up my battery to it with what cords come with it or will i have to buy more connectors for it please help
