The life of a hearing aid battery depends on its size and how well it needs to perform. If you wear your hearing aids all day, you can expect a standard disposable battery to last between 5 days and 2 weeks (based on 14 hours use a day), depending on the battery size.
However, the life will vary with your degree of hearing loss, as the more amplification needed, the shorter the battery life. It will also vary if you use a remote control or if you stream sound with your hearing aid and other devices.
The best way of preserving battery life is to turn your hearing aids off at night when not in use.
Rechargeable batteries generally last 4 – 5 years.