Rechargeable Hearing Aid batteries may be repeatedly charged and are typically charged every night to provide continual daily use. The daily battery life varies by battery size, chemistry, the amount of energy stored in the battery, the hearing aid programming,and the listening habits of the user. The batteries themselves will typically last as long as one year. There are 3 major types of rechargeable batteries.
Nickel metal hydride (NiMH) hearing aid batteries do not have sufficient energy to last a full day. In addition, they cannot be charged more than 300 times (i.e., cycle life) and, therefore, do not last a full year.
Silver-zinc batteries offer greater daily and overall battery life than NiMH batteries. Silver-zinc batteries operate on a lower voltage,(1.6-1.7V) and are non-toxic and non-flammable, and there are fewer risks if swallowed or ingested by their family, or pets.
Lithium-ion batteries, on the other hand, operate at a higher voltage (3.6-3.7V) and do carry considerable risks related to flammability and toxicity. Due to these risks, lithium-ion batteries are sealed into the hearing aid case.
Disposable batteries as a backup
Silver-zinc rechargeable hearing aid batteries are often removable from the hearing aid case, and interchangeable with disposable zinc-air batteries. This provides flexibility to hearing aid users when they go “off the electric grid”, or there is a power outage and need to use disposable batteries temporarily. Forgetting to charge your hearing aid batteries is also less of a problem when disposables are available as a backup.
How long do rechargeable hearing aids last on a single charge?
Depending on the hearing aid model, and the number of hours of wireless streaming, the rechargeable batteries provide anywhere from 7.7 (with full time streaming) to 24.7 (without streaming) hours of use time. But, wireless streaming has a significant impact on how much life you can expect out of your hearing aid battery.
Four primary factors influence battery performance:
- Advanced features
- Wireless streaming
- Amount of amplification
- Battery current drain
Modern hearing aids employ a number of advanced features, which provide louder, cleaner, more comfortable sound. Technologies like noise suppression and feedback cancellation continuously monitor and process sound in the hearing aid built-in computer. This increases power consumption leading to higher battery drain. These features not only differ among the hearing aids but also by the hearing aid user.As an example, a person with a more pronounced hearing loss may require more feedback cancellation and result in a shorter battery life.
A significant amount of energy is used every time you stream audio from your smartphone, TV, iPad, or other wireless accessories. Wireless streaming also happens when your left and right hearing aids communicate with each other to exchange audio or data.
Amount of amplification
For those with more severe hearing loss this means more power consumption. Also, if one ear has more hearing loss than the other ear, the battery life on the more impaired ear could be shorter.
Battery current drain refers to how fast the hearing aid drains power from the battery. Hearing aid manufacturers typically publish current drain figures for every new hearing aid they produce. When current drain is measured by the manufacturer, hearing aids are put into a “test mode,” which disables advanced features and wireless connectivity which under-states true battery drain in actual use.
Tips for charging your hearing aids
- Rechargeable hearing aids should be charged every night to maximize battery life. If you charge the battery every other night, this will not help extend the battery life, and could lead to issues down the road. Silver-zinc chemistry must have the opportunity to recharge to full capacity every night to get the best performance from the battery.
- Leave your hearing aids in the charger when they are not being worn. The charger will not overcharge the hearing aids and will ensure the batteries stay at full charge. Leave in the charger when not in use.
- Do not unplug the charger while the hearing aids are inserted. If the charger is not receiving power, then the hearing aids will automatically be turned on. This will cause the hearing aids to turn on, and the batteries to begin discharging.
- Remember, your hearing aids may take up to 7 hours to recharge fully, and the charging lights will turn from blinking to solid green when charging is complete.
Storing your hearing aids
- Short term storage – If you don’t plan to wear your hearing aids for a few days,leave the hearing aids in the charger with the charger plugged in.
- Long term storage it’s best to remove the rechargeable batteries from your hearing aids and store them separately.