Hello

I'm getting into electric flight after flying some Ic. I'm not toally giving up Ic its just that for me, I like to fly all sorts of models. An electric seem like a nice "fly at odd moments" model.

So

I know the differences, advantages etc between NiMH and NiCad batteries, however, when it comes to Li-Ion and Li-Poly batteries, I'm a bit lost except for the fact that I know they have very high capacities for given weight. But there must be more so could someone kindly help me out here.

Thanks.

Lithium polymer batteries are better for flying than lithium ion, they are lighter and can take a higher amp draw.
If your lost when it comes to lithiums let me try to help.
Li-poly cells are much lighter than nicds and nimh and have amazing capacities for their size( you can fly for 30 min instead of 3)
Li-poly cells are 3.7v per cell
Special skills are needed to make your own packs
You have to pick the right pack for your application or you will ruin the pack and possibly have a fire
You must have a special charger

I know that lithiums seem to have a lot of disadvantages but once you are set up and are past the learning curve you wil never want to use nimh, nicd, or fuel again.

Ok cool. So I have a small Mirage Foamie 2000 with a 400 motor which is currently being run by a 9.6v 500 Mah Nicad. Now what LiPoly would be the best choice. This plane does 100 MPH so I want simular performance.

Im not familiar with that plane, do you have any idea of your amp draw on your current setup? DR.Kiwi is pretty good at giving advice in this area so mayby he'll chime in, Im figuring that you could run a Thunder power 2100 pack and be safe on the amps, Tanics would deffintelly handle it but are harder to find. As for cell count you have two choices with the speed 400 and one is 2 cells which gives 7.4 volts( a deffinite drop in power but with reduced weight it might me alright, or you could go 3 cells 11.1v( which would up yuor power considerably and still reduce weight, but you would sacrifice motor life without proper throttle management) If you ever go brushless like with a himax 2025 then 3cells or even four would not be a problem at all.

If you want to reduce your flying weight considerably, I'd suggest a 2s2p pack of Kokam 340SHC cells (680mAh - 44g) or 2s3p (1020mAh - 66g). [I'm assuming your present 8-cell 500 weighs about 160g]. These Kokam SHC cells are said to be 20C capable but if you go with the 3s3p you'll only need ~10C to get the 10-12A your 400 will need - but with 2s (7.4v) your power will be down from your original 9.6v pack. If you don't mind frying motors, you could go to 3s2p (60g) or 3s3p (90g) - but of course, putting 120W into a 400 is not going to help its longevity.

Cheers, Phil

Yes I see....

well, I'll see about it, where can I get these packs from??? How long can I fly on a 160 gram pack then???