Apple iPod shuffle Chips, Battery, Capabilities and charging

Thanks to its built-in lithium-ion rechargeable battery, the fourth-generation iPod shuffle promises 15 hours of audio playback—a number that is a little more complex than it initially seems. First, that’s up by 50% from a claimed 10 hours in the third-generation shuffle, versus 12 promised hours in the first- and second-generation models. Second, Apple’s promised run times for iPod shuffles have always been conservative, with actual battery life surpassing the claims by variable amounts from model to model. First-generation shuffles actually ran for 16-18 hours, while second-generation models hit nearly 18, and third-generation models ran for around 12.5 in our tests.
Our battery testing for the fourth-generation iPod shuffle showed performance almost precisely in line with Apple’s claims: set at 50% volume with a pair of Apple’s Earphones connected, and randomly playing audio files at various bitrates ranging up to Lossless quality, the new shuffle ran for 15 hours and 10 minutes before chiming and turning off. While different audio settings and files can yield slightly better or worse results, this playtime places the fourth-generation shuffle ahead of the third-generation model in run time, but modestly below the first- and second-generation versions—an acceptable rather than impressive performance.
Charging the fourth-generation iPod shuffle is just like charging its predecessor. Apple’s included 45mm USB cable connects to the device’s headphone port, and provides a full charge within 3 hours, bringing a dead shuffle back to 80% of peak capacity within 2 hours. The company also sells a $19 accessory set called the iPod shuffle USB Cable with a spare 45mm cable and a 1000mm (39”) version in the same box if you want additional cables; any spare USB port or Apple iPod wall charger will work to refuel the little device. Note that the iPod shuffle remains the only iPod model that cannot simultaneously recharge and play music through headphones, as the headphone port is occupied by the special USB cable.