Here is a simple mod I made from an old capsule container I bought years ago. I use 4 AA 1.2 V 2700 Mah rechargable batteries. It has a manual switch and and LED indicator. I love it in this voltage. It is wonderful with both the 801 and the 510. Hope you like it. The finish was intended to look rough. I'll probably play around with the physical look one day.
Rannie
Rannie