A few other things to consider.

If you are running rechargeable batteries - say NiMH AA's then you are down to only 7.2volts.

Also how is the weight of the 9.6v pack compared to the AA's.

I personally would try it - figuring it close enough not to generate too much smoke. But if you try it and you fry it then you are back to square one.

Post some pics and let us know what you decide to do and how it works