1. The size of the battery
Most of today's hearing aid batteries come in three sizes: size 10, size 312, and size 13. Size 10 — the smallest in physical size — has a shorter battery life, as there is less room to store the ingredients needed to power the battery. Size 312 and 13 batteries are larger and can hold more ingredients, resulting in a longer battery life.
2. Hearing aid usage
Hearing aid users are highly encouraged to wear their hearing aids for most of their waking hours to obtain maximum benefit and value. The amount of time the hearing aid is in use will have a large impact on the life of the hearing aid battery.
3. The hearing loss
As the severity of an individual's hearing loss increases, more amplification is needed, which increases the current and, therefore, reduces the battery life. In other words, the harder the hearing aid has to work, the harder the battery has to work to provide sufficient amplification, which greatly affects the battery life.
4. The features in the instrument
Today's digital hearing aids are capable of providing many different features and functions. Some of these include: Bluetooth connectivity that allows you to stream music, television, and telephone directly into the hearing devices; noise-cancellation features; and sound generators for tinnitus patients. All of these features will also impact one's hearing aid battery life.
Using or storing your batteries in very high humidity, low humidity, or extremely hot or cold weather can impact how long the batteries will last.