A company called Lilliputian Systems wants to replace heavy laptop and mobile phone chargers with a small fuel cell system that runs on butane cartridges. The system can store 5-to-10 times more energy than lithium ion batteries, and recharging it is as fast as swapping out the cartridge.

The company, which has been operating largely in secret for several years, has started showing its first product to potential customers and says that it plans to have them on the market by the middle of next year.

Fuel cells for portable electronics have been a long time coming, held up by a number of things, including technical challenges and questions about whether they'll be allowed on airplanes.

Mouli Ramani, speaking at an MIT Enterprise Forum event this week, said that because the company will sell the butane in sealed cartridges with identification chips, they will be allowed on airplanes. And he claims that they've worked out the technical challenges too. Next up: getting the devices into the marketplace. Their plan is to use a business model something like that used by razor companies, which make money their money on disposable cartridges. Each butane cartridge, which will have enough juice to recharge an iPhone 16-to-20 times, will sell for something like $1 to $3, with the fuel cell charger costing about $200 initially, and eventually going down to about $100. Ramani says that the company plans eventually to incorporate their fuel cells directly into mobile phones and other consumer electronics.

The new system seems to have better energy density than a similarly-sized fuel cell product we recently mentioned. That one only has enough power for five or six charges.