How Long will my hearing aids batteries last?
Everything you need to know about Hearing Aids’ Batteries
Modern hearing aids pose a unique challenge to engineers today. There is a constant drive to add new features while retaining a compact size, or even reducing it. This presents a challenging set of requirements to the battery being used, where low supply voltage is a necessity and low power consumption is critical.
A number of chemistries are used in batteries today for consumer products. The most widely used chemistry for hearing aid batteries is zinc-air. Providing high-performance, eco-friendly, safe and at the same time cost-effective: the zinc-air battery is an attractive energy storage technology of the future. https://www.sciencedaily.com/releases/2021/01/210104110405.htm
The difference between Zinc-air batteries and others
Zinc-air batteries are different from most other batteries in that they “breathe” oxygen from the air for use as the cathode reactant. The virtually limitless supply of air enables the zinc-air cell to offer many performance advantages when compared to other batteries. https://en.wikipedia.org/wiki/Zinc–air_battery
Consumers often question why their watch battery lasts years and their hearing aid battery must be changed every 1-2 weeks. Although they both utilize low power semiconductors (1.5 volts), the level of sophistication in a hearing aid compared to a watch is dramatic. The integrated circuits used in hearing aids are highly sophisticated, using hardware platforms that are responsible for the customization of amplification and manipulation of sound. Hearing aid integrated circuits may also serve user interface and wireless communication functions. To power these devices, it is necessary to develop batteries that provide high-energy density, flat discharge characteristics, high current capability and are environmentally safe. Zinc-air is the ideal chemistry for this demanding environment.
Why Zinc-air Batteries are widely used for hearing aids?
The zinc-air battery was first discovered in the early 19th century but did not find its first commercial use until the 1930s. The world of zinc-air today includes a variety of button cell sizes used in hearing aids, including 10A, 312, 13 and 675. Each cell size provides the highest energy density for its size. The overall size also denotes the operating range, defined as milliamp hours.
Zinc-air exhibits a long shelf life; the rated storage life is more than three years. Storing these batteries at room temperature will result in only a 2% shelf-life loss per year.
The cells are packaged with an adhesive tab or seal that inhibits gas and vapor transfer, resulting in the battery staying dormant until ready for use. The batteries are activated once the tab is removed, allowing oxygen from the air to enter the battery. It’s good practice to gently wipe the battery with a cloth to remove any residual adhesive left from the tab on the surface of the battery. The manufacturer of the zinc air batteries also suggests that once you take the tab off of the battery, allow 2 – 5 minutes before closing the battery door on your hearing aid for maximum usage.
Nominal voltage levels are attained a few seconds after the tab is removed. It is possible to prolong the life of the battery by re-covering the air holes with the tab after each use, but the benefits of this are dependent upon the environmental conditions and are not recommended.
Your hearing aids batteries matter
Batteries play a crucial role in high-performance hearing aids. Zinc-air batteries have been widely used to deliver the high demand current requirements in hearing aids since the early 1980s. Because they provide up to three times the energy of other common batteries in a smaller size, zinc-air will continue to be an ideal choice for hearing aid makers. Future hearing aids will be developed using smaller integrated circuit geometry, solidifying the need for efficient low voltage, high-energy density batteries. Zinc-air is the ideal choice for today and the future.
Carrying for your hearing Aids batteries
If you want to ensure that the battery and hearing aid lasts, care is essential. Caring for your hearing aids involves storing it at the right temperature and washing your hands before changing the battery. Also removing a dead battery straight away can help.