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Hopefully, you don’t have smoke alarms and carbon monoxide detectors that keep beeping and chirping all over the house with low batteries. If so, you’ve let it go too long and should really run to the store immediately and get them replaced ASAP.

Otherwise, we recommend stocking up on these three 9-volt batteries below to keep everyone in your house safer.

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1. EN22 Energizer Industrial Alkaline 9V Battery

EN22 Best 9 Volt Battery for Smoke Detectors
EN22 Energizer Industrial Alkaline 9V Battery
Reg: $2.95

The industry favorite 9-volt battery for battery-operated smoke alarms from a mega-brand – this is one of the best 9v batteries for smoke detectors. Also a great option for wireless microphones, guitar pedals, in-ear monitors, radios, security backup systems, and all sorts of additional use cases.

The only difference between Energizer Industrial and what you'll find in the store is the way it's packaged. Industrials come in cardboard boxes rather than annoying blister packaging. These are cheaper, less of a hassle, and every bit as powerful as the Energizers you'll find hanging on the hooks at checkout.

2. 1222 Eveready 1.5V Super Heavy Duty 9V Battery

Eveready 1222 Best 9V Batteries for Smoke Detectors
1222 Eveready 1.5V Super Heavy Duty 9V Battery
Reg: $1.95

Eveready’s original smoke detector battery. A solid inexpensive option—perfect to buy in bulk and have a pile in the closet somewhere to swap in every 6 months or so. A tried and true 9V battery for promotions, giveaways, or group handouts.

Replacement frequency will be pretty high as the shelf life isn’t as long as higher quality batteries, but for homeowners willing to get up on a ladder or stool a bit more often, the Eveready 1222 is a solid option to save a few bucks.

3. LA522 Energizer 9V Advanced Lithium Battery

LA522 Energizer Best Lithium 9V Battery for Smoke Detectors
LA522 Energizer 9V Advanced Lithium Battery
Reg: $21.49

The highest quality, longest life battery on this list – with the highest price. These are super tough and durable batteries used in medical devices and high-tech alarm systems. A great option for hard-to-reach places like a high ceiling.

When changing the fire alarm battery is a real chore, this is your best choice. Save a few bucks buying other 9-volt batteries for easier spots and spend a bit more on a LA522 for the fire alarm tucked in a corner above the stairs. The LA522 will last a lot longer.

Energizer says a 10-year shelf life, but we wouldn’t recommend waiting that long. The LA522 9V battery will safely get you 6-7 years. But again, always err on the side of caution and replace fire alarm batteries more frequently as your budget allows.

Which type of / what size battery do I need for my smoke detectors?

Usually, the smoke alarm battery will be AA (cylinder shape) or 9V (rectangular shape) depending on the year manufactured. The battery type should be displayed prominently somewhere on the battery itself.

If you need help replacing or can’t figure out how to remove there are replacement service providers out there who can give you a hand. Not a bad idea when alarms are up on high ceilings or in hard-to-reach places. Sometimes detectors are electric-powered and hardwired – in which case you won’t need to worry about replacing batteries.

How often should I change the batteries in my smoke detectors?

You’ll find smoke detectors on the market promising a 10-year sealed battery or 10 years of battery life – wrong. Don’t put your family’s safety in the care of a longshot marketing promise. Forget the manufacturer’s suggested battery life.

Temperature, installation location, and how well alarms are cleaned and maintained affect the life of the battery. Replacement age depends on a number of factors and 10 years is by far more the exception than the rule.

Swap in new batteries to your smoke alarms every six months to a year and sleep like a baby. It’s common for people to change their batteries every time they change the clocks backward or forwards. Whatever works for you.

How to replace 9V batteries in smoke detectors

  1. Remove the smoke alarm from its mounting bracket. Depending on the brand and model of the smoke alarm, you may need to twist it counterclockwise, pull it straight out, or release a locking mechanism.
  2. Locate the battery compartment (usually on the back of the smoke alarm).
  3. Gently remove the old battery, being sure to dispose of the old battery safely and appropriately.
  4. Insert the new 9V battery into the battery compartment, making sure to match the positive (+) and negative (-) terminals correctly.
  5. Test the smoke alarm by pressing the button and listening for a loud, piercing sound. This means the alarm is functioning correctly.
  6. Reattach the smoke alarm to its mounting bracket.

Get the best bulk pricing from Battery Products.

Make one order to last you several years. Enough after-work trips to the hardware store or several small purchases every year with tax and shipping stealthily piling up. Order a bunch of smoke detector batteries at a bulk discount and check the box so you can turn your attention to checking all the other ones.

Shop all bulk 9V batteries for sale online from Battery Products; alkaline 9V batterieslithium 9V batteries & rechargeable 9V batteries. Give us a call and we'll get you the BEST bulk rates.