Lilliputian Systems is getting closer to introducing a portable butane-powered charger for small electronics.

The Wilmington, Mass.-based company today announced that it has raised $40 million of a planned $60 million round to start manufacturing a pocket-sized fuel cell designed as a supplemental energy source for USB-compatible gear, such as cell phones and e-readers.

Called the USB Mobile Power System, the device can provide between 10 and 14 charges for smart phones. It’s about the size of a deck of cards and is fueled by replaceable cartridges filled with butane, or lighter fluid.

Rusnano, a government-owned entity that invests in nanotechnologies, is the lead investor. Lilliputian’s existing venture-capital backers, which include Intel Capital and Kleiner Perkins Caufield & Byers, are also investing in the round, which Lilliputian expects to close later this year or early next year. The company has raised $100 million before this round.

For the last ten years, Lilliputian has been working on its fuel-cell charging system with the goal of bringing a boost in performance over lithium ion battery back-ups. It charges at the same rate as a battery but holds five to ten times more energy per volume. That  will allow people to, for example, leave on week-long business trips without needing to bring a power cord for a cell phone, said Mouli Ramani, the vice president of business development. Because they are sealed, the butane cartridges, expected to cost a few dollars, can be carried on airplanes.

A number of companies have tried to make small fuel cells for supplemental power, but none has succeeded. Mechanical Technology Inc., for example, spent about ten years trying to make a fuel cell charger for gadgets but abandoned the effort last year. The problem with other fuel cell chargers is that they didn’t offer a significant increase in performance over batteries, Ramani says. 

Lilliputian, too, hasn’t been able to bring its product to market as quickly as hoped. In 2009, the company had talked about having its fuel cell charger available a year later. (See Lilliputian Butane Fuel Cells for Laptops and Smart Phones.)

The company’s core technology is a process for etching a solid oxide fuel cell membrane onto a silicon wafer. Since solid oxide fuel cells operate at high temperatures, it’s packaged in insulating material.

Earlier this year, it announced a distribution deal with retailer Brookstone which will sell the fuel chargers as well as the fuel cartridges, which are recyclable. Ramani said he expects to announce product availability “soon.”

As part of the investment from Rusnano, Lilliputian will create a research and development lab in Moscow and seek out manufacturing facilities in Russia as well. The wafers that hold its fuel cell membranes are made at a retrofitted Intel manufacturing plant in Hudson, Mass.

The company is primarily focused on building up its supply chain and distribution channel but it also is working at technical improvements and new products. For example, it plans to design fuel cells to be integrated into electronics, such as laptops. This sort of development, which would take multiple years, could allow for fuel cells that operate an entire week without being plugged in, says Ramani.