Time to Read: 10 minutes
In this video, Emma discusses zinc-air batteries for hearing aids and how to maximise their performance.
Watch the video or read the transcript below:
Hi there, I'm Emma from Value Hearing.
In this video, I'm going to give you some tips on how to get the most out of your hearing aid batteries.
Hearing aid batteries are not exactly the most interesting topic to make a video about but it is so important.
We get questions from our clients all the time in our clinics about hearing aid batteries:
- How do I optimize my use
- How do they work, and
- Why do they not last longer.
I feel quite passionate about zinc air hearing aid batteries.
Zinc Air Batteries are pretty amazing
They are pretty amazing, they're so tiny and they fuel these amazing tiny little computers that we call hearing aids.
It's something that I often remind my clients - that these little hearing aids, while they look quite simple from the outside, they are incredible. They're using a huge amount of energy because they have these super, super computer chips inside them that are extremely fast.
Now we have things like Bluetooth streaming happening in the hearing aids so they are heavy on the energy.
So, in order to get something that's really, really tiny, has energy density, but doesn't cost a lot. It's not the easiest fate and that's what these are.
They're cheap to manufacture in comparison to other batteries, they're hugely energy dense and they're tiny. So that's my version of defending the zinc air batteries.
A chemical reaction
But to get the most out of them really, you need to recognise that there is a chemical reaction happening here when you start to use them.
One of the first things you'll notice about these batteries when you first get them is that they come in a blister packet. They come in a packet where it is not allowing the batteries to touch each other. So, try not to remove them from the packet.
You do not want the batteries to make contact with each other. You also don't want them to come in contact with any other metal objects like coins or keys in your pocket - they're likely to short circuit or to drain each other out.
Just keep them in the original packaging, would be my advice. Or if you really have to remove them, just separate them from each other and all other metal objects.
The battery tab
The other thing you'll notice that's quite unique about these batteries is that they have a little tab on them or a little sticker.
Again this is connected to the fact that they’re a zinc air battery. That tab, that sticker, is actually a hermetic seal.
It's protecting the zinc inside the battery from mixing with the oxygen. When you want to use the battery, that is when you take the sticker off - and only then you remove the sticker.
If you look quite closely at the battery, you will see a number of tiny, tiny little holes. These are little air holes. This is the hole that the air enters in order to mix with the zinc and to create the chemical reaction to give you the energy from the battery.
Let the battery breathe
So one of the really important tips is that when you do take that tab off is let the battery breathe.
A lot of my clients find this very strange when I give them this tip. You need to let the battery sit, preferably for five minutes, that's what the research shows is the optimum amount of time.
In fact, after five minutes of breathing you're likely to get on average an extra day of battery life, so it's really, really worth investing that time. Even if you can give it only 20-30 seconds before you put it in the hearing aid, or close the battery drawer, you will get some extra battery life from it.
How to handle batteries
Okay, the other thing to bear in mind, you will have probably heard that you should wash your hands before you handle these batteries.
It's simply because oil on your hands or maybe dirt, for example, or other debris can get into these holes quite easily and block. Then you don't get as much oxygen in as you should, and then you don't get the full power from them.
So, quite important to make sure you've got nice clean dry hands.
One thing I do often tell my clients is, if they can, use the magnet tool that comes with the hearing aid. There's this great little tool, it's usually a combie tool, it's usually got a brush as well attached to it.
Essentially it's a magnet as well, that allows you to remove the batteries and to insert the batteries really easily.
Using the magnet will just keep your hands further away from the battery. Another good tip is if, when you go to bed at night, and you open the battery drawer in order to disengage it and switch the hearing aid off, it's a good idea is actually open it up the whole way just to let any moisture evaporate from the drawer and also to allow the battery to breathe.
Some people use a dry kit or a dehumidifier at night time. You shouldn't put the hearing aid batteries in those kits. Make sure that you separate them.
Let the battery breathe and let the hearing aid dry out in the dry kit.
Store away from heat, cold and moisture
Okay, so moisture mixing in with the zinc and air isn't an ideal situation for the battery speaking of which that is another tip when you're storing them at home make sure that you have them at room temperature, preferably in a dark dry area.
So not in the fridge, certainly not in a hot, humid bathroom, and not in the car.
Just somewhere nice and dark and cool and you'll find that you will get a lot more out of your batteries.
The hermetic seal is kept intact to prevent extreme moisture, humidity, heat, or cold can affect that tab.
Use the oldest batteries first
The other really, really good tip as well is, if you do have a big stock of batteries at home use the older batteries first, obviously.
They do actually have a really long shelf life but as you get closer and closer to the expiry date, which should be printed at the back of the packet, you'll notice you may get a little bit less energy from them.
Disposing of spent batteries
So good if you've got a big stack of batteries, look at the expiry date and use the oldest ones first. Another question that comes up quite a lot is, ‘can I dispose of them in the normal rubbish?’.
Technically they're not counted as a biohazard so the recommendations officially are that you can just dispose of them in your normal household rubbish.
However it is much better to recycle them and it's quite easy to recycle them.
Most audiology clinics will accept bringing back your batteries for them to recycle on your behalf. Or here in Australia, for example we have battery disposal bins in all Aldi's right across the country.
And I'm sure in many other countries there will be other supermarkets or services offering something similar. So there you go, those are my top tips for getting the most out of your hearing aid batteries.
Do remember they're powering really powerful tiny little computers.
