https://www.instructables.com/Replacing-the-Battery-in-Bontragers-Ion-700-Bike-L/
Replacing the Battery in Bontragers Ion 700 Bike Light : 4 Steps (with Pictures) - Instructables
Replacing the Battery in Bontragers Ion 700 Bike Light: My Bontrager ion 700 headlight is a few years old and it stopped working suddenly after a long ride....