At 10,000mAh, Moshi's new IonBank 10K ($110) has a relatively high capacity by USB battery standards. The silver and white battery pack is a rounded rectangle, with two USB ports on one of the long edges, next to five battery indicator lights and a power button. Combined, the ports can put out 3.6A of power, so you can charge one iPad at full-speed, plus another at partial speed. The most interesting aspect of the pack is the sliding cover, which…