A:Answer I have not tested how long the batteries will run from a full charge until they no longer function, but I do not need to since the batteries are rechargeable, which was a primary factor in deciding on any headphone. Thus far I have used the headphones for up to five hours with no issue. By placing the headphones on its stand, a red LED light comes on indicating the batteries are being charged, and the light goes out when the batteries are fully charged, which is a good design. My old headphone’s rechargeable AAA batteries lasted over 10 years, so I expect these batteries (same Ni-MH type) to last for many years, and should the batteries no longer hold a charge, replacements are readily obtained via Amazon.
