Nintendo Wii Fit Plus + DDR Exercise Combo #2 (Balance Board + Wii Fit Plus Game + Battery + Bag + Mat + Sleeve + DDR Hottest Party Game + 4 x Original Konami Dance Pad)
Amazon.com: RepairBox Battery Cover for Wii Fit Balance Board : Video Games
OEM Genuine Nintendo Wii Balance Board Battery Compartment and PCB Board - Surpius
Wii Fit Balance Board 3800mah High Capacity Rechargeable Battery Pack | eBay