Any ideas for Zoombak extra battery life / external battery

This is more of what I'm trying to figure out. I'm thinking what I might try is to measure the voltage output from the ZoomBak battery box and splice a same voltage lithium ion battery pack to one of the power cords and voilà! Ultimately I would like to obtain two weeks of tracking so I'm thinking that I would need a substantial battery.

Also, I suspect the internal batteries that Zoombak uses are not of the highest quality. I bet by replacing the internal battery with a higher quality equivalent could boost tracking life by a day. That would be a good prophylactic for those quick 24-hour tracks that go bad.

Blair, monitoring something (or someone) for the length of time will require some serious engineering. Since you are very mysterious about your task I can only throw some general things out here that I would be thinking of. Is your object powered by any power source (i.e. a vehicle)? Any chance of tapping into that power source? Any chance for a solar charger? Is your object big enough to use multiple batteries connected by a battery switch that allows switching the batteries at a certain amperage to a new battery if connect in parallel? How stealth does your black ops have to be? The parts and pieces are all out there, just a matter of finding the right ones for your ops. You also realize that the link mayer suggested will give you an extra 10 days per pack, so that is pretty close to your goal. and if you take one of these power extenders and modify the power connection from the existing 4 AA batteries and just add 2 packs of additional four batteries to it, just give you plenty of mAh for your expeditionary tracking.