Amazon.com: Synergy Digital Remote Control Battery, Works with Logitech Harmony 900 Pro Remote Control, (Li-Ion, 3.7V, 950 mAh) Ultra High Capacity Battery : Electronics
Kastar 3-Pack Battery and LTD2 USB Charger Compatible with Logitech Harmony 895 Harmony 900 Harmony 900 Pro Harmony 900 Remote Harmony One Advanced MONSTER AV100 MONSTER AVL300 MONSTER AVL300S - Walmart.com
Amazon.com: Replacement for Logitech Harmony 900 Battery - Compatible with Logitech Universal Remote R-IG7 Battery (950mAh 3.7V Lithium-Ion) : Electronics
Kastar Battery AC Wall Charger for Logitech Harmony 900 Remote Harmony One | eBay