During the iPhone 5s and iPhone 5c introduction earlier this week, Apple talked up battery life, but didn't mention any specifics around what size power plant would reside in the back of the new phones. Enter Brian Klug of AnandTech, who has been doing a little digging:
"While poking through the FCC documents and piecing together a story on the network band situation for the iPhone 5S and 5C, I remembered that part of a normal disclosure is in fact battery size. Apple noted the battery on the iPhone 5C increased, and I've been curious about the 5S battery size as well given the different PCB photos with slightly changed aspect ratio that floated around as potential candidates for the 5S. Apple also doesn't disclose the battery size in Whr or mAh on their tech spec pages, making this the only real place to find out outside of opening them up and looking once they're available."
What that translates to is increased capacity from the 1440mAh currently available in the iPhone 5. The iPhone 5c is only slightly increased at around 1507mAh, while the iPhone 5s goes up yet further to around 1570mAh. It's important to remember this information comes from FCC documents and not Apple themselves, though it's not unreasonable to believe that they're accurate.
Of course, battery capacity is only half the story, especially in the higher-spec'd iPhone 5s. What matters to us, and to Apple, is battery life. For that, there's only one true test. And that begins September 20.