Recently picked up this mint 1.42 GHz 14" iBook G4 (2005), the last and fastest iBook. I was surprised that both the PRAM and main batteries hold a decent charge, even 17
Apple iBook 12 inch G3 G4 Laptop Battery A1061 - 6 Cell 5200 mAh - YouTube
Apple Powerbook G4 Battery 12 inch Aluminum - 661-2787 661-3051