Is there a big down side to having a 9 cell NIMH battery pack other than weight. If you system can handle that voltage.
If your ESC can handle a 9-cell, it should be able to handle 3s (aside from the lipo cutoff).
As far as just running a 9-cell, there should be no problems with running it, other than it being able to fit in the battery tray
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The reason I was asking I saw some Gens Ace 5000mah nimh out there but they only have 9 cell in stock.
With a 3s Lipo, you have more power and punch. You will also have longer continuous power and runtimes.
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