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best batteries for smoke detectors

Best Batteries for Smoke Detectors

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This article provides you with the key things you need to know when choosing the best batteries for smoke detectors.

Batteries are not all created equal.

The life expectancy and power output vary depending on the chemical composition. Manufacturers design batteries for different purposes.

It is essential to buy batteries designed to power smoke detectors.

Batteries for smoke detectors have to be tested regularly.

Sometimes people forget, so it is essential to purchase the correct model for your needs so that you can be confident that your smoke detector can work reliably.

It is also important to have spares and be confident that when you need them, that they are in good health, even if it is a year or more since you bought them.

I recommend a pack size that provides you at least one or two spares, so they are available when you need them.

They often seem to go flat at inconvenient times.

When batteries get old, chemicals can leak out.

These chemicals are corrosive and can damage the device they are powering.

Some manufacturers guarantee that they will either repair or replace your device if corrosive materials from the battery damage it.

The 3 best batteries for smoke detectors - Reviews:

1. Duracell CopperTop 9V Alkaline Batteries | Long Lasting, All-Purpose 9 Volt Battery | 4 Count: Most Dependable

Duracell Coppertop 9V Alkaline Batteries

Duracell recommends this model for smoke detectors.

The CopperTop 9V alkaline battery was designed to deliver long-lasting performance, something that is especially important for a smoke detector, given you may only check that they are working correctly every three months or so.

Duracell alkaline batteries are guaranteed to hold their charge for five years in storage, which is great because it is essential to keep some spares, but it could be a long time before they are needed.

A pack of four batteries is a suitable size for a smaller house or apartment.

The Duracell packaging is ‘reclose-able’ which reduces the risk of moisture and any corrosion, which could impact on the life span and condition of this product.

Duracell Coppertop batteries should protect your device from damaging leaks of corrosive chemicals.

Should any device be damaged due to a battery defect, Duracell will repair or replace the item at their option.

Some chemicals are harmful to the environment.

Duracell eliminated mercury from their batteries as it can pose a health or environmental risk in regular use and when disposed of.

These are manganese dioxide batteries.

2. Energizer Max 9V Batteries, Premium Alkaline 9 Volt Batteries (8 Battery Count): Most Useful

Energizer 9V Batteries

The Energizer Max 9V batteries are designed for everyday low to mid-drain devices, and smoke detectors belong in that category.

They are also suitable for devices like toys, flashlights, clocks, and remotes.

They come in a pack of eight batteries, which is excellent for a medium to a large house, to ensure you always have a replacement when you need it.

Unused batteries store their power for up to 5 years, providing peace of mind that they will work when you need them, even if you have had them for a while.

Energizer batteries are designed to prevent damaging leaks, and they warrant that they will replace your device if damage caused by the battery does occur.

Some chemicals are harmful to the environment.

Energizer created the first zero mercury alkaline battery. Mercury can pose a health or environmental risk.

These batteries are composed of Zinc-Manganese Dioxide.

3. ACDelco 9 Volt Batteries, Super Alkaline Battery, 4 Count Pack: Most Advanced

ACDelco 8-Count 9 Volt Batteries

ACDelco 9 Volt Super Alkaline Batteries are equipped with advanced technology you can count on. They deliver optimal power you can depend on for a variety of household devices, including fire alarms, intercoms, walkie-talkies, smoke detectors, carbon monoxide detectors, clocks and more.

ACDelco super alkaline batteries deliver long lasting maximum power that is consistent and reliable. They perform better than the competition in high-drain and super high-drain devices, and they provide consistent discharge performance.

The impressive seven-year shelf life with stainless steel pre-coating that prevents leakage and advanced ingredient formulation helps maintain power over time. ACDelco alkaline batteries are built to last.

The 9V batteries contain no mercury or cadmium, making them a smart choice for your family and for the environment.

AC Delco 9v Batteries are a bargain and great value for money!

Frequently Asked Questions:

When to replace a smoke detector battery? 

Opinions are divided as to whether you should replace your smoke detector battery when it is still working. In my opinion, what is most important is how often you check it.

Some organizations recommend checking all your smoke alarm batteries with a test, once a month. It is an excellent habit. Smoke detectors are there for a reason.

They could save your life or help prevent your house from burning down. That must be worth a few minutes of your attention regularly.

Many people recommend checking twice a year on the date that daylight savings begins and ends. If you do that, you should be sufficiently covered, but you should still be alert to low battery warnings.

Batteries always display a ‘Use-by’ date.

The life expectancy is something you need to check, especially if you have had the batteries for some time. 

You should check this when your batteries arrive as well, to make sure you do have the amount of time as specified in the manufacturer’s specification. 

Occasionally old stock may be accidentally mixed with the newly manufactured product.

How often do smoke detector batteries need to be replaced? 

If you do not check your batteries regularly, then I would recommend replacing the batteries once a year, just to be sure.

That would be the trade-off between having a regular checking routine and having to purchase new batteries more often.

The exception to this will be if you have the more expensive Lithium-Ion batteries which can last for several years.

The risk is that you forget when you purchased them and keep putting off testing because you know they should be suitable for several years.

Another thing to consider is that not every product is perfect and other than if it is not working at all, you would have no way of knowing, other than testing.

The more often you test your batteries, the less often you will have to replace them.

How to remove smoke detector battery? 

If you are not sure how to remove a battery from your smoke detector, refer to the printed ‘Guide’ that came packaged with the device.

If you no longer have it, refer to the web site for the brand and model you own.

Often you need to twist or turn the alarm and remove it from the mounting plate to access the battery holder.

The battery compartment usually has a plastic clip, which you need to carefully open, to gain access to the battery.

You can then gently pry the battery from the clip, which will be very firm.

How to change a smoke detector battery? 

When you remove the old battery, as explained above, take note of which way the two wires on the clip sit in the compartment.

You will want to put the new battery in and have the cables running the same way so that they sit nicely inside the battery compartment and do not get pinched or damaged when it goes back in.

If you didn’t take note when you removed the old battery, you would find that, as you insert it into the compartment, it goes in easier one way than the other.

You will notice that the battery has one terminal larger than the other as does the connector in the smoke detector.

When plugging it in, hold the battery so that the small terminal is touching the large one on the clip and vice versa.

Then apply equal pressure, pushing the battery onto the terminals, and it will click into place.

When putting the battery detector back into the mounting bracket, hold it square and slowly turn the smoke detector clockwise with gentle pressure.

It will slide into the mount and then you can gently turn it into place until it locks into the mount.

How to change smoke detector battery when it is hardwired?

The first thing you need to do is turn off the power to your wired smoke detector at the circuit box or switchboard, to ensure you can’t get an electric shock.

Find the battery cover panel as described above. Sometimes the battery compartment lid will have a screw holding it in place.

Make sure you have a screwdriver that fits the screw correctly as the wrong size can damage the screw.

Now you can remove the old battery and replace it in the same way as described above.


Fire is a serious hazard, and your smoke detectors are only as good as the batteries you purchase and the frequency with which you check and replace them.

The first thing to consider is how many batteries you need based on how many smoke detectors you have mounted in your home, making sure you have at least one or two spares.

The chances are that the time you become aware of a flat battery is in the middle of the night when you are trying to sleep. 

The last thing you want is to find out then that you do not have a spare battery in the house. 

Then you will have a smoke detector that is not working for you.

Batteries are not all made equal, and I would consider the brand reputation and guarantees that the manufacturer makes concerning leakage risk and any damage that could be caused by a faulty or poorly manufactured battery.

Finally, when the batteries arrive, check the use-by date and make sure that it meets your expectations.

It does not happen often, but even the most reputable brand can occasionally get old and new batteries accidentally mixed up in their distribution system.

In the unlikely event of this occurring, a reliable brand will sort this out for you quickly and easily.

The life expectancy is important given it might be a year or more before you need the spares.

Feel free to send your own reviews and comments below.

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