
Liquidmetal is an ultra-lightweight, high-strength, scratch-proof metal. It's been used in the SIM card ejection tool shipped with the iPhone 3G and 3GS, in fact.
Why a fuel cell component, or to be precise, an “amorphous alloy” collector plate for a fuel cell? A fuel cell uses hydrogen and a catalytic reaction to generate electricity. Using a fuel cell instead of a lithium polymer battery, a mobile phone could last as long as 30 days without recharging and notebooks could run for 20 hours or more. At that point, of course, more fuel must be added, and that means more hydrogen.
The collector plate in the Apple patent is the catalyst itself. Typical of a hydrogen fuel cell, its waste products are heat and water. The problem so far has been developing the right materials for these fuel cell components, and Apple's patented collector plate might be the answer.