There are many brands and sizes of hearing aid batteries; all batteries are Zinc-Air type. These Zinc-Air batteries last longer than standard mercury batteries. Hearing aid batteries do not drain like standard batteries. These batteries will go from full power to almost drained in an instant. This makes it hard to tell how much longer the battery will last without using a battery tester. Having extra batteries on hand is always recommended.
Several factors affect the life of your hearing aid battery. The more severe your hearing loss, the more amplification is required. This increase reduces the battery life. The number of hours a day you use your hearing aid affects the length of battery life. The more features a hearing aid has, the faster the battery is used up. Lower temperatures, higher altitude and amount of humidity all negatively affect the battery life.
All these factors lead to each person going through batteries at their own speed. A good way to measure your hearing aids’ battery life is to write down the date you put the battery in and the date you take it out. Keep a list for all batteries from one package. Once you have used up the package you should be able to identify your range. Typically, a battery will last anywhere from one to four weeks.
As batteries get smaller, their storage capacity and battery life decreases. There are five common battery sizes (largest to smallest)
#675 is used in the behind-the-ear model
#13 is used in the in-the-ear model
#312 is used in the in-the-canal model
#10 is used in the completely-in-the-canal model
#5 is used in the smallest completely-in-the-canal model
Fiddling with small hearing aids and the even smaller batteries can be difficult, especially for those with dexterity issues. Tools are available to help with the removal and insertion of the batteries. Rechargeable batteries are another option; instead of having to remove the batteries, the entire device is simply placed on a charger every night.