CNET

One of the most oft complaints about electronics is battery life. Digital cameras, smartphones and laptops can all run out of power when you're least prepared. It appears Apple is searching for a way to fix this problem.

The tech giant filed a patent application, which was published by the US Patent and Trademark Office on Thursday, for a "Fuel Cell System to Power a Portable Computing Device." Simply put, this would be an internal power system that could run a laptop for "days or even weeks without refueling," according to the application.

In the patent application, which was first reported by 9to5Mac, Apple describes a way for fuel cell power sources to be designed into electronics without adding a lot of extra weight. Fuel cells tend to be compelling because of their ability to pack a lot of energy into a relatively small package, compared to a battery.

While a number of different products have been developed for charging electronics, few have taken off. Typically, fuel cells for electronics are designed for portable charging, in which a person carries a fuel cartridge that's about the size of a roll of coins and can recharge a smartphone or music player. But Apple envisions fuel cells built directly into electronics.

The way fuel cells create electricity is by combining a fuel, such as hydrogen, with an oxidizing agent, like oxygen or air. The technology has gained increased attention over the past few years because not only could it replace batteries, it could also be used as an alternative to traditional fossil fuels, like oil and gas.

While hydrogen is a common source of fuel for the technology, Apple's patent outlines a number of potential fuel sources, including sodium borohydride and water, sodium silicate and water, lithium hydride and water, magnesium hydride and water, among others -- including liquid hydrogen and compressed hydrogen gas.

This isn't Apple's first patent application for a fuel cell system. In 2011, the company filed a similar application for such a system for a "portable computing device." In March, the USPTO published an Apple patent application for an external fuel cell system to power mobile devices.

Apple didn't respond to a request for comment.