Logitech's new iPad keyboard case has a four-year battery life - The Verge
Logitech Ultrathin Keyboard Cover for iPad mini (White)
Amazon.com: NewPower99 Battery Replacement Kit with Battery, Video Instructions and Tools for Logitech Illuminated Living-Room Keyboard K830 : Electronics
Best Buy: Logitech Ultrathin Keyboard Cover for Apple® iPad® Air Black 920-005510