Hi Richard,

I too have some experience with gel cells. We used them years ago as battery backup for security systems. Of course, my system is man-portable, which means a battery pack like you're describing would be a bit much. Not many men could lug it around, even with a shoulder strap. On the other hand, I do understand that not all gel cells are that big.

In fact, my original thought, first blush sort of thing relying on the aforementioned past experiences, was to put a gel cell battery and charger circuit in the case such that it was only necessary to plug the system into the wall to recharge it. But it occurs to me that to demonstrate a system that is truly field functional I should make the battery quickly changable, just like cordless power tools, and rechargable in less time than it takes a fresh battery to deplete. And by providing parallel battery sockets it could even be possible to change batteries without powering down the system.

Anyway, the idea of using existing parts from a commercially available product seems to me the best way to go. It will involve the least amount of reinventing a wheel on my part. After all, this prototype is not about demonstrating a next generation battery charger.

Thanks,

Joe