This seems interesting, if a little pricy:

Brunton Hydrogen Reactor

Just saw it this morning.

It looks like the big advantage of it is that you can store it practically forever without self-discharge. The other advantage is that you can carry more than one hydrogen cartridge for a minimal increase in weight and bulk. The recharging unit ("hydrolyser") costs $250. The cartridges, at $15 each or 4 for $50, aren't that expensive and are supposedly good for 1000 refills.

I haven't seen specific power-density figures but "iPad-recharging caps out at about 1.5 times per fully-juiced cell." That's about 12,000 mAh. Size is 5.3 x 2.9 x 1.3" and weight is 8.5 oz with one hydrogen core. Compare that to the largest of my collection of portable LiPo battery chargers at 4.8 x 3.1 x .9", 13 oz, and 18,000 mAh. In other words, the Brunton unit is lighter but bulkier and more expensive to operate.

My needs for portable recharging revolve around air travel, power outages, day hikes and the occasional night or two in the boonies. For that, a LiPo battery makes more sense to me. Hard core backpackers and adventurers would probably be better off with the Brunton unit.

Interesting. If I understand the article correctly, this product is basically just the hydrogen half of a traditional fuel cell (which is why the article mentions that you can't recharge something inside an airtight bag or on the Moon).

The bit about keeping the units below 120 degrees seems a bit limiting as far as taking this unit along with you, whether you're just a business traveller or an outdoors type. On a hot summer day, it would be easy to reach that temp if left in a parked vehicle. Hopefully that's just a conservative temperature rating.

Recharging the Hydrogen Fuel Cartridges could be a problem in an emergency.

I am currently using the following for outdoors power generation;

http://www.amazon.co.uk/New-Trent-iCarri...words=new+trent

http://www.amazon.co.uk/EasyAcc-charger-...=solar+panel+6w

http://www.amazon.co.uk/OUTDOOR-Powerpot...ywords=powerpot

I was wondering about that too. Apparently, there is a separate $250 "hydrolyser" that requires an AC outlet to recharge the hydrogen cartridges and it takes about an hour for each. But they seem to have good shelf life, so you could keep a few in reserve.

I like the 2 amp charging capability and the reusable cells. I don't like the extra $250 piece of equipment to charge the cells.

Right now, I am not seeing how this would trump my current Goal Zero setup.

This device just shows that technology is advancing, and I am sure that there will be improvements and advances from this. I do not think it is ready to replace my other charging options, but it is very interesting.