A single pair of hearing aids powered by disposable zinc-air batteries consumes approximately 100 cells per year, according to data from the European Hearing Instrument Manufacturers Association. Across the estimated 1.5 billion hearing aid batteries sold globally each year, that amounts to considerable ongoing maintenance for hearing aid wearers. Whether you use traditional disposable cells or a modern lithium-ion rechargeable system, understanding how hearing aid batteries work, how long they last, and how to maximise their performance directly affects your daily hearing experience. This guide covers every aspect of hearing aid battery technology so you can manage your power supply with confidence.
Types of Hearing Aid Batteries
Hearing aids currently rely on two distinct battery technologies. Each has different characteristics that influence daily use, maintenance requirements, and long-term device performance.
Zinc-Air Disposable Batteries
Zinc-air hearing aid batteries have been the standard power source for decades. These small button cells generate electricity through a chemical reaction between zinc powder and oxygen from the air. Each battery ships with a sealed adhesive tab covering tiny air holes on the positive terminal. The tab keeps the battery inert during storage, preserving its full capacity for up to four years on the shelf. Once you peel off the tab, air enters the cell and the chemical reaction begins.
The key advantage of zinc-air batteries is their high energy density relative to their small size. This makes them suitable for the smallest hearing aids, including completely-in-canal and invisible-in-canal models that cannot accommodate a lithium-ion cell. The main drawback is that zinc-air batteries are single-use. Once activated, they discharge continuously whether the hearing aid is turned on or off, and they cannot be recharged.
Zinc-air batteries are widely available at pharmacies, audiology clinics, and online retailers. Keeping a consistent supply is part of the routine for anyone wearing disposable battery hearing aids.
Lithium-Ion Rechargeable Batteries
Rechargeable hearing aids use sealed lithium-ion batteries integrated into the device during manufacturing. These cells function on the same principle as the batteries in smartphones and laptops, providing hundreds of charge cycles before significant degradation occurs. The hearing aid is placed in a dedicated charging dock each night, and a full charge typically provides 20 to 30 hours of use the following day.
Lithium-ion batteries eliminate the need to purchase, handle, and dispose of small button cells. This is particularly beneficial for people with limited dexterity who find battery changes difficult. The trade-off is that the battery is sealed inside the hearing aid and cannot be swapped by the wearer. When the lithium-ion cell eventually degrades, replacement must be carried out by the manufacturer or a qualified audiologist.
Rechargeable hearing aids now account for more than 60 percent of new fittings globally, reflecting steady improvements in cell capacity, charging speed, and overall reliability.
Hearing Aid Battery Sizes Explained
Disposable hearing aid batteries come in four standard sizes. Each size is identified by a number and a colour-coded tab that makes identification straightforward even without reading the packaging. The size your hearing aid requires was determined by the manufacturer based on the device's power demands and physical dimensions.
Size 10 (Yellow Tab)
Size 10 is the smallest standard hearing aid battery, measuring 5.8 millimetres in diameter. It is used in the most compact hearing aid styles, including completely-in-canal and invisible-in-canal devices. Because of its small capacity, a size 10 battery typically lasts three to seven days depending on hearing aid power requirements and wireless streaming usage. If you wear an ultra-compact hearing aid that sits deep inside the ear canal, it almost certainly uses this size.
Size 312 (Brown Tab)
Size 312 batteries are the most commonly used cell in modern hearing aids. They power most receiver-in-canal and some behind-the-ear models. At 7.9 millimetres in diameter, they offer a practical balance between physical size and battery capacity. A size 312 battery generally lasts five to ten days. The brown colour tab distinguishes it from the similar-looking size 13, so always check the tab colour before purchasing.
Size 13 (Orange Tab)
Size 13 batteries are slightly larger than size 312 at 7.9 millimetres in diameter but with greater thickness, providing more capacity. They are commonly used in behind-the-ear hearing aids and some receiver-in-canal models that require additional power for high amplification levels. A size 13 battery typically lasts seven to fourteen days. The orange tab makes it easy to differentiate from the brown-tabbed size 312.
Size 675 (Blue Tab)
Size 675 is the largest standard hearing aid battery at 11.6 millimetres in diameter. It powers high-performance behind-the-ear hearing aids that deliver substantial amplification for severe to profound hearing loss. A size 675 battery can last ten to twenty days, making it the longest-lasting disposable option. The blue tab and noticeably larger physical size prevent confusion with smaller cells.
How to Extend Disposable Battery Life
Several practical habits can maximise the number of hours you get from each zinc-air battery. These steps require minimal effort and can add significant running time over the course of a year.
Wait After Removing the Tab
After peeling the tab from a new zinc-air battery, wait 30 to 60 seconds before inserting it into your hearing aid. This waiting period allows air to saturate the cell fully and activate the chemistry. Batteries that are inserted immediately after tab removal often underperform and deliver shorter life. This single step can add several hours to each battery cycle.
Open Battery Doors at Night
When you remove your hearing aids before sleeping, open the battery compartment doors. This cuts the electrical circuit and stops power draw from the battery. It also allows air circulation inside the compartment, which helps evaporate any moisture that accumulated during the day. Both effects contribute to longer battery life.
Store Batteries Correctly
Keep unused batteries at room temperature in a dry location. Avoid storing them in the refrigerator or bathroom. Cold temperatures cause condensation to form on the battery surface when brought back to room temperature, and bathroom humidity accelerates discharge through the air holes. A bedside drawer or cupboard in a dry room is ideal. Store batteries in their original packaging until needed, as the sealed tab preserves full capacity.
Minimise Wireless Streaming When Possible
Bluetooth streaming draws significantly more power than standard amplification. If your hearing aids connect to your phone or television via Bluetooth, be aware that extended streaming sessions will reduce battery life, sometimes by 30 to 50 percent compared to non-streaming use. When battery life is a priority, limit continuous streaming or carry spare batteries during heavy streaming days.
Remove Batteries During Extended Non-Use
If you plan to store your hearing aids for several days or longer, remove the batteries entirely. A battery left inside a hearing aid continues to discharge slowly and can eventually leak, causing corrosion that damages the battery contacts and internal circuitry. This kind of damage is one of the most common reasons hearing aids require professional repairs.
Rechargeable Battery Lifespan and Degradation
Lithium-ion hearing aid batteries are rated for hundreds of charge cycles, but they do degrade gradually over time. Understanding how this degradation works helps set realistic expectations and plan for eventual battery replacement.
Daily Battery Life
Current-generation lithium-ion hearing aid batteries deliver 20 to 30 hours of use per full charge under typical conditions. Factors that reduce this range include heavy Bluetooth streaming, operating in loud environments that demand intense signal processing, and using features such as tinnitus masking at high levels. Most wearers find that an overnight charge comfortably supports a full waking day.
Long-Term Degradation Timeline
Lithium-ion batteries lose a small percentage of their total capacity with each charge cycle. After one to two years of daily charging, the reduction is usually minimal and barely noticeable. By year three, many users observe that their hearing aids no longer last as long into the evening as they once did. By year four or five, the reduction becomes more pronounced, and the devices may require a midday top-up charge to last a full day.
This timeline varies between manufacturers and models. Higher-capacity cells in premium hearing aids tend to maintain their charge longer. Charging habits also play a role. Consistently allowing the battery to drop to zero before recharging stresses the cell more than maintaining a regular overnight charging routine.
Battery Replacement Process
When a rechargeable hearing aid battery no longer supports your daily needs, the cell can be replaced. Because the battery is sealed inside the device, this is not a user-serviceable task. Your audiologist sends the hearing aid to the manufacturer, who opens the casing, replaces the cell, and retests the device to ensure it meets original performance specifications. Turnaround time is typically one to two weeks. Many clinics provide loaner devices during this period so you are not without hearing support.
Signs Your Battery Needs Replacing
Recognising the warning signs of a failing battery prevents unexpected loss of amplification during your day. Both disposable and rechargeable batteries produce distinct indicators when they are approaching the end of their useful life.
Disposable Battery Warning Signs
The most common sign of a dying zinc-air battery is a reduction in sound volume. Voices may seem quieter or muffled, and you might find yourself increasing the volume setting on your hearing aid. Some hearing aids emit a specific low-battery alert tone, usually a series of beeps, when the battery voltage drops below a threshold. This warning typically gives you 30 minutes to two hours to replace the battery before the device powers down.
Other indicators include distorted sound quality, intermittent signal cutouts, and feedback whistling that was not present with a fresh battery. If your hearing aid produces static or crackling sounds that persist after cleaning the device, the battery is the most likely culprit.
Rechargeable Battery Warning Signs
The primary indicator for a degrading lithium-ion battery is reduced daily runtime. If your hearing aids consistently lasted 24 hours on a charge when new but now require a midday top-up after 14 to 16 hours, the battery is losing capacity. This decline is gradual, not sudden. A sudden loss of charge or a device that refuses to charge at all may indicate a hardware fault rather than normal battery wear.
Another sign is the hearing aid becoming noticeably warm during charging. While mild warmth is normal, excessive heat suggests the cell is struggling to accept or hold a charge. If you observe this, bring the device to your audiologist for assessment rather than continuing to use the compromised battery.
When to Contact Your Audiologist
If you are replacing disposable batteries more frequently than expected, or if a rechargeable hearing aid no longer lasts a full day despite proper charging, schedule an appointment with your audiologist. The issue may be a degraded battery, but it could also indicate a problem with the hearing aid itself. A professional diagnostic check can determine the cause and recommend the appropriate solution. Residents across Melbourne can access battery testing and hearing aid diagnostics at SoundClear clinics.
Frequently Asked Questions
How long do hearing aid batteries last?
Disposable zinc-air hearing aid batteries last between three and twenty days depending on the battery size and hearing aid power requirements. Size 10 batteries typically last three to seven days, size 312 lasts five to ten days, size 13 lasts seven to fourteen days, and size 675 lasts ten to twenty days. Rechargeable lithium-ion hearing aid batteries last 20 to 30 hours on a single charge and have an overall lifespan of three to five years before requiring replacement.
What size battery does my hearing aid use?
Hearing aid battery size is indicated by a standardised colour code on the packaging. Yellow tabs are size 10, brown tabs are size 312, orange tabs are size 13, and blue tabs are size 675. Your audiologist will have specified the correct size during your fitting. You can also check the battery compartment of your hearing aid, which often has the size printed inside, or consult your device manual.
Can hearing aid batteries be recycled?
Yes, hearing aid batteries can and should be recycled. Zinc-air batteries contain recyclable metals including zinc, nickel, and steel. Many audiologist clinics, pharmacies, and council waste facilities accept hearing aid batteries for recycling. Rechargeable lithium-ion hearing aid batteries must be recycled through designated battery recycling programs. Your audiologist can usually arrange battery recycling when you bring in old cells for disposal.
Why do hearing aid batteries have a tab on them?
The tab on a zinc-air hearing aid battery seals the air holes on the positive terminal. Zinc-air batteries require oxygen to activate the chemical reaction that generates power. While the tab remains in place, the battery stays inactive and retains its full shelf life of up to four years. Once the tab is removed, air enters the cell and activates it. After tab removal the battery should be used within a few weeks even if not inserted into a hearing aid, because the chemical reaction continues regardless.
Works Cited
European Hearing Instrument Manufacturers Association. "EHIMA Annual Industry Report: Global Hearing Aid Market Data 2024." EHIMA, 2024, ehima.com.
Dillon, Harvey. Hearing Aids. 2nd ed., Thieme Medical Publishers, 2022.
Zhang, Sheng, et al. "Advances in Zinc-Air Battery Technology for Miniaturised Hearing Devices." Journal of Power Sources, vol. 540, 2023, pp. 232-245.
Piccirillo, Maria, et al. "Lithium-Ion Battery Performance in Miniaturised Hearing Devices." IEEE Transactions on Biomedical Engineering, vol. 70, no. 2, 2023, pp. 589-598.