Review: IMAX B6 multi-battery type charger

I just got an Imax B6 AC/DC clone yesterday. I know nothing about the operation of this thing so I know RTFM applies and I did make a go of it. I have not had much time to really play with it, I'm waiting on magnets which will help. I tried to charge an 18650 this morning. I am sure I had all the settings right to charge the single cell @1A. When I held down the start button I received an alarm indicating that the battery voltage was too low. Well it was too low, 2.73V, but thats why I was trying to charge it. I then tried to charge another 18650 that was 3.92V and that looked like it was going well. I stopped that because I was just holding the leads on to see if it would work. It started charging at .2A then moved to .3A before I stopped. Sound normal? I dont get that I cant charge a battery that has low voltage.

That is a safety function, you are not supposed to charge LiIon if they are too much discharged.

You might want to check two other safety functions: Maximum charge time and maximum mAh. The time might break the charge if you use a low charge rate.

I was able to figure out how to discharge an 18650 and I am now charging the same battery at 1A. I have not figured out how to get deeper into the menu yet for the safety functions but I'm searching YouTube vids to help. The discharge terminated at 3V. Is this too far?

That is fine, if you check the battery with a DMM you will see the voltage is significantly higher, because the battery recovers when the load is removed.

Depending on what LiIon cell you are testing, the minimum varies between 2.5 volt and 3 volt. In my tests I uses 2.8 volt, this is a habit I got from the CBA, that uses this as the default value.

Thanks HKJ. That helps.

Is this how I set up to charge batteries in parallel?

Yes, that is correct. The terminals can be connected anywhere along the lines. It doesn't necessarily have to be in the middle.

Can hobby chargers be used to test efficiency of led drivers at different voltages?

No, they are designed as constant current devices, not constant voltage devices. There voltage regulation is usual very slow, this works fine with batteries, but would not work very well with a led driver.

Just make sure the batteries have the same or very close in the same voltage

Yes, that is very important if your charging cells in parallel that they be no more than 0.5V difference. The sudden in rush of current will be greater due to the imbalance of voltage and thus cause damage to cells that can't handle that much charging current.

IMO your better off series balance charging

Not really, series balance charging requires all batteries to be of equal capacity (or else it’ll take years to charge them all), while parallel balance charging only requires similar SOC (easier to achieve, especially if you parellel-charge cells that you use in 1 multi-cell light)

IMO your better off series balance charging, even more so for muti cell lights

Even less so, you mean ;)

Balancers CAN be inaccurate (especially in cheap B6 knock-offs), parallel charging will ensure that all cells are at SAME voltage and there can't be any inaccuracies (like with balancers)

Right. I'm working on figuring that one out now. Have to buy the leads first I guess then I will figure out how to use them.

Ive just recieved my icharger last week. I ordered leads from where Benkie linked to and got magnets of ebay. Just be careful soldering the magnets though as heat kills them. Been playing today with a couple of Flea Bay batteries to get the hang of it. Very impresive. The wiring is not as complicated as it looks once you get your head around it.

https://budgetlightforum.com/t/-/3118

post 43

Unless your making sure cells are the same voltage its risky parallel charging, you will increase the IR of the batteries that will affect the end voltage of the cells and the amount power the cell can give over time as the cells fight each other with sudden discharging and charging to self balance when you connect them.

If you series balance with a cheap clone charger yes it might be out 0.04 volt out per cell, but there is a good chance in you parallel you still will be out around 0.04 to 0.06 volt due the inaccurate calibration of the main charge leads.

I series balance charge 2 x 2400 2 x 2600 and 2 x 3100 mAh cells all at once with in 0.001 volt and still can charge them a lot faster then a xtar wp 2 charger 2 at a time thats with in 0.03 volt and charge them faster then an imax clone.

It also depends on your charger the cheap clones can be slower to balance charge then the more bigger $$$ chargers, but you still will save time if you charge more then one or two at a time. IMHO lower amp charges in series your batteries will last longer then higher amp charges in parallel some thing Ive notice over years of RC.

I may have changed these settings when I was screwing around with the charger but I didn’t think I went into the NiMH settings. It looks like the default setting for NiMH discharge is .1A and down to .1V, seems to low on both counts. What should these values be? I must have changed them at some point.

Yeah way to low, i use these settings

AAA 0.2 amp AA 0.5 amp D 1 amp to 0.85 volt per cell for nimh, for nicad's 0.9 volt per cell max.

For some good cheap nimh and nicad battery holders and other hobby charger acc, check this thread out.

https://budgetlightforum.com/t/-/1621