RC Tank Warfare community hobby forum

Has anyone fitted two NI-MH in parallel into their vehicle for a greater run time?

Yes.

Yes. I did it on my T-34 since the battery packs on it are really small. My packs use XT60 connectors so I made an XT60 to dual XT60s so I can run dual packs in a tank anytime I want and I can remove the Y connector when I don't want to.

Glad to know I am not the only one. That will stop an argument.

So long as you wire the batteries in Parallel, and not series, you can't do any harm - the tank can fry its circuits instantaneously with a single pack if you get a motor stall, having 2 battery packs doesn't increase that risk.
Generally you should have packs of similar capacity so that they discharge at the same rate, and one pack doesn't start to drain charge from the other as it drops off, but so long as they are plenty big enough to begin with its not an issue.

I have two 2000 mAh lipos in my Sherman becuase one bigger battery doesn't fit.