Hearing Aid Batteries

Hearing Aid Batteries

Hearing aids are becoming smaller and more powerful all the time, whether they run on standard or rechargeable batteries. While a rechargeable battery needs to be charged regularly, standard hearing aid batteries are disposable and need to be replaced. In this section, you’ll find all the information about buying and changing your hearing aid batteries. 


In the past, mercury zinc batteries were the most common type of hearing aid battery. But now zinc-air batteries are more popular – this is because they’re more eco-friendly and they maintain a constant voltage.

This explains why the holes in hearing aid batteries are sealed with special protective foil before you use them! Before you insert a battery into your hearing aid, you need to remove this protective foil. Since the battery only begins to work once the foil is removed, it may take a moment for the power to reach your hearing aid.


A zinc-air hearing aid battery works like this:

  • Small holes in the battery’s surface allow air to penetrate it.
  • The air reacts with the zinc inside the battery, producing zinc oxide.
  • This reaction creates the battery’s energy.

Once you’ve removed the protective foil from the battery, it begins to create energy, and there’s no way to stop it! So make sure you only remove it when you’re ready to put the battery in your hearing aid.

Hearing aids don’t always have to be powered by standard, disposable batteries. Some hearing aids are available with rechargeable batteries. If you have rechargeable hearing aids, you don’t need to buy new batteries for it: once the battery runs out of power, you just recharge your hearing aids.


You need one hearing aid battery per hearing aid.

This depends on the type of hearing aids you have and the type of batteries they use, as well as how long you wear your hearing aids for. A size 10 battery in a hearing aid with lots of advanced features might last between three and five days, while a larger, size 13 battery in a hearing aid with simpler functions could last for up to three weeks.

Just like regular batteries, you can get different brands of hearing aid batteries, and they come in different sizes too.


Behind-the-ear (BTE) hearing aids usually take size 13 and 312 batteries, while in-the-ear (ITE) hearing aids usually use size 312 or 10 batteries.

When you’re fitted with your hearing aid, your Hearing Aid Audiologist will make a note of what size batteries you need.


If you can’t remember what size batteries your hearing aid needs, you can pop into your local 20dB Digisound Care Centre for advice or call our friendly Customer Care team on 6338 9626

Hearing aid type Colour code Diameter Height Capacity Voltage
675 Blue 11.6 mm 5.4 mm 650 mAh* 1.4V
13 Orange 7.9 mm 5.4 mm 310  mAh 1.4V
312 Brown 7.9 mm 3.6 mm 180  mAh 1.4V
10 Yellow 5.8 mm 3.6 mm 100  mAh 1.4V

*mAh = milliampere hours


The first step is to remove the protective foil from the batteries. It takes around two minutes after this for your battery to reach full power, so you might choose to wait before you insert them into your hearing aids. Make sure you insert the batteries with the minus and plus sides the right way round. If you find that the battery compartment won’t close, or is difficult to close, it’s usually because you’ve got the plus and minus back to front!

If your hearing aid doesn’t seem to be working even after you’ve fitted the new battery, try checking that there’s no contamination in the battery compartment, as this can interfere with the connection. You could also try a different battery in case it’s a manufacturing problem.



Batteries should be stored at room temperature. Make sure you keep them out of reach of children and pets.

As soon as your hearing aid batteries run out, remove them from your hearing aid just in case they start leaking or expanding.