Your hearing aid worked perfectly yesterday, so why has the sound suddenly become weak, crackly, or disappeared altogether? In many cases, the answer is surprisingly simple: the battery. Yet choosing the right replacement isn't always straightforward. Different hearing aids use different hearing aid battery sizes, and using, storing, and replacing them correctly helps maximise both performance and battery life.
This hearing aid battery guide explains how zinc-air batteries work, how to identify the correct battery size, how long hearing aid batteries last, and the simple habits that help you get the most from every battery. You'll also learn how to tell when it's time to replace the battery and when the problem may lie with the hearing aid itself.
How Hearing Aid Batteries Actually Work
Most hearing aids use zinc-air batteries, which only begin producing power when they're exposed to air. That's what makes them different from the batteries used in most household devices.
Each battery has a small coloured tab that seals tiny air holes. While the tab is in place, the battery remains inactive. Once you remove it, oxygen enters the battery and triggers a chemical reaction that starts generating power.
From that moment on, the battery is activated, whether you place it in your hearing aid immediately or not.
To get the best performance:
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Remove the coloured tab.
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Wait 2 to 5 minutes before inserting the battery.
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Close the battery door and switch on your hearing aid.
Giving the battery a few minutes to activate fully before use helps it deliver more consistent performance and can maximise its usable lifespan.
Which Size Do You Need? The Colour-Code System
Hearing aid batteries come in four standard sizes, each identified by a number and a universal colour tab. Checking the number and colour tab makes it easy to identify the correct replacement battery.
|
Battery Size |
Colour Tab |
Typical Hearing Aid Type |
|
10 |
Yellow |
Small completely-in-canal (CIC) and invisible-in-canal (IIC) hearing aids |
|
13 |
Orange |
Behind-the-ear (BTE) and in-the-ear (ITE) hearing aids |
|
312 |
Brown |
Receiver-in-canal (RIC) and many behind-the-ear (BTE) hearing aids |
|
675 |
Blue |
High-power behind-the-ear (BTE) hearing aids |
Not sure which size you need? Check:
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Your hearing aid user manual.
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The battery is already fitted in your hearing aid.
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The manufacturer's recommendations.
Always use the recommended battery size, as hearing aid batteries are not interchangeable.
Getting the Longest Life While You're Wearing It
How long do hearing aid batteries last? It depends on the battery size, your hearing aid model, wireless features, and how many hours you wear your hearing aids each day.
Typical battery life is:
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Size 10: Around 3–7 days
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Size 312: Around 3–10 days
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Size 13: Around 6–14 days
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Size 675: Around 9–20 days
Actual battery life varies depending on daily wear, streaming features, and hearing aid settings.
To help your batteries last longer:
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Turn your hearing aids off when you're not wearing them.
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Leave the battery door open overnight to reduce moisture build-up.
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Keep your hearing aids dry by removing them before showering or swimming and wiping away sweat after exercise.
Moisture can reduce battery performance, so keeping your hearing aids as dry as possible helps maximise battery life.
Storing Spare Batteries Correctly
Proper storage helps unused hearing aid batteries last longer and perform reliably when you need them.
Store spare batteries at room temperature in a cool, dry place. Avoid storing them:
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In the refrigerator or freezer.
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In bathrooms or other humid areas.
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On sunny windowsills.
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Near radiators or other heat sources.
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Inside parked cars during very hot or cold weather.
Although refrigeration was once recommended, modern zinc-air hearing aid batteries perform best at normal indoor temperatures.
Avoid buying more batteries than you'll use within a reasonable time, as even unopened batteries lose effectiveness over time. Keep batteries in their original packaging until you're ready to use them. This helps protect the air holes from accidental activation.
Signs a Battery Is Failing (And When It's the Hearing Aid, Not the Battery)
Most hearing aid batteries gradually lose power before they stop working completely. Common signs that the battery needs replacing include:
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Lower overall volume.
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Crackling or distorted sound.
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Sound cutting in and out.
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Warning tones or low-battery alerts.
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Sudden loss of power.
A fresh battery usually resolves these issues. If it doesn't, the problem may be with the hearing aid rather than the battery. Moisture, earwax blocking the receiver, or a fault with the microphone or speaker can all affect performance. If your hearing aid still isn't working properly after replacing the battery, arrange an assessment with your audiologist.
Final Thoughts
Choosing the correct battery size, storing spare batteries properly, and replacing batteries when needed can help keep your hearing aids performing reliably and reduce unexpected interruptions.
When it's time for a replacement, explore Ballyduff Pharmacy's Hearing Aid Batteries collection to find the right batteries for your hearing aid.