The Best 9v Battery For Smoke Detector

There’s nothing more frustrating than being woken up in the middle of the night by a chirping smoke detector. You think to yourself, “Whelp, the battery must be dead. Time to replace it.”

But what battery do you get? Which of the many 9v batteries out there is the best 9v battery for smoke detectors?  This time, you want to make sure that you replace the batteries with ones that will last! Enough of these middle of the night wake up calls.

It’s very important that you don’t wait on replacing that battery. It’s a very serious safety issue if you decide to wait. So I suggest stocking up on the best 9 volt batteries in this post and replacing them right away.

In this post, I’ll review what I believe to be the 3 best 9v batteries for smoke alarms. You can replace them with any 9v, but these will definitely last a lot longer than the standard 9v.

Best 9V Battery For Smoke Detector (Quick List)

(Reviews) Best 9V Battery For Smoke Detector

The Energizer Ultimate Lithium 9v is a super high quality battery with an incredibly long life span. The main reason these make my top choice as the best 9V battery for smoke detector is because these batteries are tough durable batteries that many medical facilities trust to use in their devices. Even the high tech alarm industry uses these 9v batteries in their devices.

As you know, changing smoke alarm batteries can be a difficult task, especially when they’re located in high, hard to reach locations. But when you replace your worn out smoke alarm battery with an Energizer Ultimate Lithium, you can count on it lasting for a very long time.

Energizer says that this battery has a 10 year shelf life, but we wouldn’t recommend waiting that long. You could, however, safely get 6-7 years out of it though. With that said, I still like to change my smoke alarm battery every year, 2 years at most.

The Energizer Industrial 9 Volt battery is another great option for your smoke detector. It a very dependable battery that delivers the power needed to your smoke alarm.  These 9 volts contain the long lasting power which is found in the Energizer Max alkaline.

The Energizer Industrial batteries are specifically designed for use in professional applications and in my opinion are a dependable and very affordable option.The alkaline cells offer a potent Zinc-Manganese Dioxide chemistry that gives them the power needed for high drain devices like cameras and the longevity needed for smoke detectors. Their affordability and longevity makes them a great choice for use in your home’s alarms.

With an expected life of around 7 years, you can easily buy them in bulk and simply keep them around the house for when that smoke alarm starts chirping in the middle of the night. There’s nothing worse than not having one on hand when you need it.  

Outstanding performance and quality combined with a great price make the Energizer Industrial 9 Volt batteries an excellent choice for smoke detectors.

The Ultra Life 10 Year Smoke Alarm Battery is the first long lasting Lithium 9-Volt made.  It’s a batter made for smoke alarms. This battery is also a pretty popular choice for carbon-monoxide detectors, wireless security devices and music and audio devices.

Each of these batteries are rated to have an operating lifespan of up to 10 years in single station ionization type smoke detectors, and will even last up to 10 years just simply sitting in storage.

That means th Ultra Life smoke alarm batteries will last up to 5 times longer than alkaline 9v batteries.

These quality smoke alarm batteries have the highest energy density, flattest discharge voltage curve, longest shelf life, widest operating temperature range, and lightest weight of any comparable 9-volt battery.

There’s a good reason the after introducing these batteries 20 years ago, Ultralife has sold over 100 million of them!

What Is a 9 Volt Battery

Andrea Cannon from Wisebread.com defines a 9 volt battery as: “A 9 volt battery is a power source commonly used in small electronic devices, home appliances, and home security devices. They can easily be replaced and installed, the same as you would an AA battery or an AAA battery.

She goes on to say that 9 volt batteries were, “...first introduced for transistor radios in 1956 and are commonly used in professional and home use today. They have a rectangular shape with rounded edges and are constructed of six 1.5V LR61 cells. Lithium batteries tend to work longer for high-drain devices, while alkaline batteries offer a more affordable option for low-drain devices.”  

Thanks Andrea for that awesome explanation of what these batteries are.

(Buying Guide) 9v Battery For Smoke Detectors

Batteries play a hand in the overall running costs of home devices, but to keep expenses down, you’ll need to pick the right battery for your needs. There are two popular battery types: Single-use batteries and rechargeable batteries.

Can Rechargeable Batteries Be Used In Smoke Detectors?

It’s not unheard of for people to use rechargeable batteries in their smoke detectors and have never had a problem with it. However, the manufacturers of these rechargeable batteries recommend that you don’t use them for smoke detectors.

So with that said, I’m going to also recommend that you follow the manufacturer's recommendation and not use rechargeable batteries in your smoke detectors.

Use Disposal Batteries For Smoke Detectors

Disposable batteries are made to be thrown away. Then once all the power is used up, the battery is thrown away. The lifespan of these disposable batteries can vary pretty widely. Depending on what type of battery it is, disposable batteries may last between 7 to 15 years.

There are two different types of disposable 9v batteries, both of which are mostly the same, however there are some differences. The two types of disposable batteries are:

  • Alkaline Batteries

  • Lithium Batteries

Alkaline Batteries

Alkaline batteries are best used in devices that drain power slowly such as LED lights, clocks, remote controls and kids toys. Alkaline batteris can be used in things that drain power faster, but expect the battery to lose its power much faster.

If you have tools or appliances that sit unused for long periods of time, but you need them to fire up right away, then alkaline batteries might be the best option..

Alkaline Pros

  • Best for low drain devices

  • Easily available

  • Affordable

Alkaline Cons

  • Due to the high replacement rate, most of these batteries will end up in the landfill.

Lithium Batteries

Lithium batteries have a much higher capacity than their alkaline counterpart. They also have a slightly higher initial voltage as well as a longer shelf life. Lithium batteries are able to store more energy than any other kind of battery that’s of a comparable size. Because of this, lithium batteries are the best choice to use when it comes to devices that have a high drain, because the battery will typically last much longer in these kinds of devices compared to alkaline batteries.

With that said, however, lithium batteries can really pack a punch because of how much power they are capable of holding. This makes lithium batteries too powerful to use in some devices and can even damage internal circuitry if not careful. Always be sure to read and follow the manufacturer’s recommendations for what type of battery to use.

Lithium Battery Pros

  • Best used in high drain devices

  • Longer shelf life (Longest life single use battery type)

  • Lowest overall weight

Lithium Battery Cons

  • More expensive than alkaline batteries

  • Higher voltage can potentially damage device

How Often Should You Change Smoke Detector Batteries

Many smoke detectors available today claim that they’ll keep the battery for 10 years. Although that might be the case, I’ve never been one to try and test that out.

There are too many variables at play that can alter the lifespan of a 9v smoke detector battery. For example, a few things that affect battery life are:

  • Temperature

  • Installation location

  • The cleanliness of the smoke alarm itself

When I moved into my first house, I was told to be sure to replace the batteries in the smoke detector every year. So that’s exactly what I do, and it’s what I recommend to anyone who asks.

So in order to have more peace of mind, change the batteries in your smoke detector every year.

And to help me remember this, I try to change the batteries on my birthday. Another tip you can use is to write the date you replaced the battery on the battery itself. Use a sharpie and simply write the date on it. You’ll always know how long that battery has been in the smoke alarm.

It’s also common practice for people to change their batteries every time they change the clocks backwards or forwards.

Final Thoughts

If you’re looking for a high quality smoke detector battery that’s rated to last a very long time and give you the peace of mind that your family is safe? Then without a doubt the Energizer Ultimate Lithium 9V is what you’re looking for

These are one of the most popular 9v batteries used for smoke alarms for a good reason.  They’re dependable and they’re affordable.

You can check them out right here.

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