Charger & Battery Help Requested

[Percymon 2184]

Err i'm not expert but i think there is constant voltage and constant current charging modes dependent upon battery type.

I remember all sorts of rubbish off the net so i could well be wrong but might give you an avenue to investigate further !

this might help Rob..its an extract from a wider article here .. http://www.rchelicopterfun.com/rc-lipo-batteries.html

Most good RC LiPo battery chargers will use the constant current / constant voltage charging method (cc/cv). All this means is that a constant current is applied to the battery during the first part of the charge cycle. As the battery voltage closes in on the 100% charge voltage, the charger will automatically start reducing the charge current and then apply a constant voltage. The charger will stop charging when the 100% charge voltage of the battery pack equalizes with chargers constant voltage setting (4.2 volts per cell) at this time, the charge cycle is completed. Going past that, even to 4.21 volts will shorten battery life.

Now given that 4.2V is the upper safe limit when charging a 3.7V pack i'd suggest you leave well alone with the charger setting.

[Rob Buckle 1]

this might help Rob...

It did indeed, thank you. Feel a bit stupid now for not searching myself, sorry.

So, while voltage is 3.7v per cell, or 2 x 3.7 = 7.4v for a 2S battery - all of which I knew - cell voltage at 100% charge is 4.2v per cell - which I did not know - and that value should not be exceeded.

Good. Now I know not to change the default value of 4.2v but am free to adjust the value for amps. I have the charger set to "Auto 1C" charge at present, but when charging it appears only to peak at about 3.5 amps, instead of 5 amps, which I understand should be 1C for my 5000mAh battery. Not sure what is going on there, but I may manually bump up the amps to 5. This should not be a problem as my battery is rated for up to 2C charge rate.

Thanks Percymon.

[Singapore_959 18]

No problem at all. 0.2v doesn't make that much difference. I even run my Tamiya MFC-02 on 2S Li-Po.

Hi Mark,

very interested in this. It is absolutely no problem using 2S lipo with the MFC-02?

I want to use one in a boat ! and am concerned if it will a) work with a 7.4 4500mah lipp saddle pack, and b ) if the MFC will can handle prolonged full throttle runs of a 540 or one of those shortened tuned 540 motors Tamiya makes for M chassis' (direct to prop drive).

[Singapore_959 18]

Hi Mark,

very interested in this. It is absolutely no problem using 2S lipo with the MFC-02?

I want to use one in a boat ! and am concerned if it will a) work with a 7.4 4500mah lipp saddle pack, and b ) if the MFC will can handle prolonged full throttle runs of a 540 or one of those shortened tuned 540 motors Tamiya makes for M chassis' (direct to prop drive).

Mark, wondering if you could please advise?

Thanks