Got my new 9AN yesterday and noticed a couple of things:
1. It's heavy.
2. The battery pack rattles inside.
3. The low output beam sucks.
So, this made me think about the battery packs. As the battery pack is 130 mm long, two 18650 would fit, just.
you mentioned that a fully depleted B90 pack would output over 3.5 V. How come? Don't you discharge both NiCd and NiMH to 1.0 V?
I was thinking about reducing weight and improving the battery capacity to 4.8 Ah using standard LG's.
If Li-Ion is a no-go, I still have questions.
1. What color will your new packs have? Anything but blue would be nice so you can distinguish original packs from the replacement packs easily.
2. What diameter are you aiming at? I understand that your replacement pack must it the 8A*, it wouldn't like it to rattle inside 9ANs either. Is there a good compromise?