Amazon.com: ZZcell High Capacity Battery Replacement for Harman Kardon LI11B001F Onyx Studio 1, Onyx Studio 2 Only (Not Compatible with Studio 3) : Electronics
LI11B001F Battery for Harman Kardon Onyx Studio 1 2 Speaker 3400mah
HOW TO HARMAN KADON ONYX STUDIO BATTERY UPGRADE - YouTube