Know the Law
- Recent legislation in some states and municipalities has increased the popularity of the 9V Lithium battery as they are now requiring a 10 year lithium battery in many smoke detectors and this is the only battery that will satisfy the requirement.
- Oregon, Louisiana, and Michigan are known states with smoke detector battery requirement laws. The city of Madison, WI is an example of a municipality with smoke detector battery requirement laws. The popularity of these laws continue to increase so be sure to check with your local authorizes to make sure you’re complying with the rules and regulations.
Know your battery options:
Best: Rayovac 9V Lithium
- This battery is the most powerful battery so it will give you the longest service life in your smoke detector. If you have a free standing smoke detector, either ionization or photoelectric, you should use this battery as these detectors depend soley on you replacing the battery to ensure they work. This battery will last up to 10 years in ionization smoke detectors and up to 7 years in photoelectric smoke detectors (both free standing versions).
- People with hardwired smoke detectors should consider this battery to save time in replacing smoke alarm batteries. Many people use this battery for those hard to reach smoke detectors that require a lot of effort to test and change the battery.
- We recommend you continue to test your smoke detector at a minimum of twice a year in the rare case of either a smoke detector or early battery failure. A great reminder is to test them every time you change your clock for daylight savings.
- Where to buy: This is available nationwide at Home Depot and is a great value for a 2 pack at $9.97. This can also be found in many other area hardware stores and other local retailers.
- Please note that Energizer also carries a 9V lithium product however, it will not last 10 years in a free standing unit as it has lower miliamp hours.
Better: Rayovac 9V Alkaline
- This is the most popular 9V battery chemistry sold because of its reasonable cost and great service life. This battery will last up to 5 years in an ionization smoke detector and up to 3 years in a photo electric alarm (both free standing versions).
- We recommend you continue to test your smoke detector at a minimum of twice a year in the rare case of either a smoke detector or early battery failure. A great reminder is to test them every time you change your clock for daylight savings.
- Where to buy: this is the most widely available 9V battery. You will find this in most major retailers including Walmart, Target, and Menards, as well as local grocery, hardware, and other stores. At Walmart a 3 pack of Alkaline 9V batteries costs $5.97
Good: Rayovac 9V Heavy Duty
- This is the standard battery that many inexpensive smoke detectors come with. This is the least expensive option and it also has the shortest service life, only lasting up to 2 years in an ionization smoke detector and only up to 1 year in a photoelectric smoke detector (both free standing versions).
- This battery is ideal for families or businesses that have a routine to change their smoke detector batteries either bi-annually or annually.
- We recommend you test your smoke detector monthly in the rare case of either a smoke detector or early battery failure.
- Where to buy: This is available nationwide at Walmart where a 2 pack costs only $0.97. There is limited availability elsewhere.
Remember, never use a rechargeable battery in a smoke detector as brands vary greatly on how fast they lose their charge (some lose it in just one month) and are not designed for usage in smoke detectors.
Also, remember when purchasing brands other than Rayovac performance may be lower than we stated in our recommendations on the Rayovac products above.