Hi,

I've been using some older 170 mAh PowerEx 9.6V rechargeable 9V NiMH batteries for my Sennheiser wireless microphone system. There are some higher capacities out there, so I'm wondering if I should upgrade to the 230 mAh 9.6V or chance using the 300 mAh 9.0V .

http://www.thomas-distributing.com/maha-9v-rechargeable-battery-300mAh.php

They're listed as excellent for pro audio, Wireless microphones, but I'd rather go with an opinion from this board. Has anyone tried these 9.6V 300 mAh batteries ?

After speaking to Eugene Thomas at Thomas Distributing, I've learned that these batteries are larger than the 170/230 mAh 9V's and may not fit in some wireless microphone setups. I'll buy one of the 300 mAh to check with my Sennheiser wireless system.

Here are some good pictures of NiMH and Alkaline discharge curves. Since the capacities aren't stated and given the rapid improvements in NiMH capacity, the NiMH X-Axis time scale should be much closer to that of the Alkaline.

http://lib.store.yahoo.net/lib/zbattery/nimh-curve.gif
http://lib.store.yahoo.net/lib/zbattery/alkaline-curve.gif

from this source:
http://www.zbattery.com/rechargeablebatteries.html