Battery too hot!

[DirtRider045]

I can't figure out why my NiMh batterys are running so hot in my mamba max brush-less rustler. I have ruined two traxxas power-cell batterys because they have overheated, they were both 7 cell, 8.4v 3000 and 3300 mAh. I just purchased an 8 cell, 9.6v 5000 mah. I'm a nitro guy so I'm not familiar with electric but i figured a higher voltage and mAh would help with this problem, please fill me in with anything I'm doing wrong!

 

[frickenjoey]

That is because the Mamba Max tries to pull more amperage out of the batteries than they can supply. They will melt down too...I know I did the same thing with mine. You would have to gear down a ton or maybe switch to a milder motor. That is what I had to do before I went all lipo.

 

[DirtRider045]

So do lipos not overheat because they can supply enough amperage?

 

[frickenjoey]

They can overheat and sometimes to yes....but the average Lipo can supply more juice than a NiMh ever could. A 5000mah 30C would do great in it; twice the punch and longer run times too. Now be careful on E-bay batteries...I got burnt on some of those. They were serious crap....lesson learned for me. They sucked pretty bad. Work good in my roto start though. HobbyKing has some pretty good Lipos and they are cheaper than most NiMh packs even.

 

[DirtRider045]

Your pretty convincing, i may have to switch over to lipo after i burn up my new nimh, which probably wont take long!

 

[frickenjoey]

My decision was made when I smoked a $80 NiMh pack first run out of the box....I got soooo fed up that nothing could stand up to the Mamba with out melting down that I switched. I use these in my 4x4 Slash and they are great so far. So they are lighter, longer run times and more power....ok twist my arm a bit harder? Also for $30 a pack? Can't beat it at all!
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=9436

 

[hamz9561]

LiPo is the only way to go with brushless. I've ruined a couple of packs with a Mamba Micro Pro. I went LiPo and never looked back.