AA battery

[ernest2]

i am converting a tamiya pt-15 into an rc model. i'm putting a graupner mini-jet drive and 540 size motor. now with a 7.2ni-mh battery pack, i'm a bit worried that it might be too heavy for such model (19" x 5" approx). so i was thinking of making a 7.2v pack from AA size. but i'm not sure if such batteries will be able to cope up with the load. any thoughts

ernest

[patmat2350]

The latest NiMh cells can put out 10x their rated capacity... so a 2200 mAh cell (or pack of cells) can put out 22000 mA (22 amps). You're probably not using that much... but you can always test it and see!

PM

[waboats]

i am converting a tamiya pt-15 into an rc model. i'm putting a graupner mini-jet drive and 540 size motor. now with a 7.2ni-mh battery pack, i'm a bit worried that it might be too heavy for such model (19" x 5" approx). so i was thinking of making a 7.2v pack from AA size. but i'm not sure if such batteries will be able to cope up with the load. any thoughts

ernest


Doable with a little care... Nimh would be best.
Watch the heat inside the plastic hull.. Keep the Amps down as much as possible..

Heard of somebody doing something similar but are using a 400 on the Mini-Jet to save extra weight. Needs an engine mount adjustment of some sort I would guess..

A pair of small Lipo's run together might be worth a look..

[Ghost 2501]

as for heat issue, you could glue railway tracking in strips to the battery to act as a heatsink

[Kmot]

Ernest: An "AA" battery is quite long, and I think a better solution for you would be the 2/3A battery. You can make up a pack of those, in the same voltage, and it will be much smaller in size and lighter in weight.

http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=138

There is also 1/3AA:

http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=1016

And 2/3AA:

http://www.all-battery.com/index.asp?PageAction=VIEWPROD&ProdID=1017

[ernest2]

well i have given it a thought, and since my current bunch of AA's are 600mah, that will probably mean i still need to buy 2000++mah AA's, so i think i will have to compare it first the price between AA and 2/3A, and maybe 4/5SC.
regarding heat, i am not worried about the heat from battery but more from the motor as the motor will be very close to the hull.