Are Button Batteries Dangerous? Why Older Gadgets Need a Check

Yes. Button and coin batteries are dangerous to young children, and the danger is not choking. When one gets stuck in a child's throat, it can burn through the tissue in as little as two hours, according to the U.S. Consumer Product Safety Commission (CPSC). From 2011 through 2021, the CPSC counted 27 deaths and an estimated 54,300 emergency-room visits linked to swallowed or inserted button batteries.

A federal rule known as Reese's Law now requires battery doors on new products to be child-resistant. What most articles leave out is that the rule only covers products made or imported after 23 October 2023. That matters for the remote, key fob or flameless candle you already own, and for anything you buy secondhand.

The law locks the battery door on new gadgets. On older ones, checking it is your job.

Why are button batteries dangerous if swallowed?

The battery does not need to be broken or leaking. The National Capital Poison Center explains that once a battery lodges in the throat, an electrical current forms around it. That current produces hydroxide, a strong alkaline chemical, which burns the tissue. Most swallowed batteries pass through on their own, but nobody can tell beforehand which one will get stuck.

The poison center says to be especially careful with batteries about the size of a penny or larger. It names 20 mm lithium coin cells, often marked CR2032, CR2025 or CR2016, as among the most dangerous. Those are the flat silver coins found in many car key fobs, kitchen scales and light-up toys.

The center also warns that a battery pushed into a nose or ear can cause permanent injury. And the CPSC is clear that children should not play with or handle these batteries at all, used or new.

What does Reese's Law actually require, and from when?

Reese's Law was signed on 16 August 2022. In September 2023 the CPSC turned a voluntary industry standard (ANSI/UL 4200A-2023) into a mandatory rule. Under it, a battery compartment must either:

• need a tool, such as a screwdriver or coin, to open, or
• need at least two separate movements made at the same time to open by hand.

Products must also pass tests that copy rough everyday use and misuse, and carry warning labels.

You will find two different dates online, and they confuse people. The Federal Register notice clears it up. The rule took effect on 23 October 2023 for products made or imported after that day. The CPSC then gave companies a grace period, ending 19 March 2024, during which it chose not to enforce the rule while testing labs caught up. So both dates are real, but 23 October 2023 is the dividing line.

Two more details from the rule are worth knowing:

• Toys follow their own federal toy standard for battery access, so a toy that meets that standard is exempt from Reese's Law. Children's items that are not toys, such as light-up shoes, must meet Reese's Law.
• Batteries themselves sold after 12 February 2023 must come in child-resistant packaging.

Which everyday items use button batteries?

More than most people think. Drawing on the poison center's list:

That last row is the busy one right now. Halloween wands, glow headbands and finger lights are everywhere at the end of October, and party favors follow in December.

Are cheap light-up toys still being recalled in 2026?

Yes, regularly. Two recent CPSC recalls show the pattern:

• May 2026: about 124,560 ZMC Group light-up toys, including Halloween wands, headbands and a flashing whistle necklace, sold at discount stores nationwide for about $1 from May 2023 to April 2026. The CPSC said children could easily reach the button batteries.
• September 2026: about 179,739 Cade California Electronic finger lights, sold in 50-piece boxes online from March 2015 to July 2026 for $5 to $16. Each light held three button batteries, again easy for children to reach.

No incidents were reported in either case, but notice the sales windows. Items sold for years before a recall are still sitting in drawers, toy bins and donation boxes. That is exactly where the secondhand risk lives. You can check any item by name on cpsc.gov before you buy; our guide on how to check if a product is recalled walks through it.

How do you check an older or secondhand gadget? A 6-step checklist

Use this on anything with a coin battery, whether it came from a yard sale, an online auction, a relative's house or your own junk drawer:

1. Try the battery door with one thumb. If it slides or pops open with no tool and a single movement, it does not meet today's standard.
2. Look for a screw. A small screw holding the cover shut is the simplest sign of a secured compartment. Make sure the screw is there and turns tight.
3. Check for cracks. A cracked case or a broken clip can expose the battery even when the door is fine. The CPSC says to stop using, repair or throw out an item with a damaged compartment.
4. Read the battery. If it says CR2032, CR2025 or CR2016, treat it as the high-risk type the poison center describes.
5. Tape what you keep. For a door a child could open, or one that might pop open if dropped, the poison center suggests strong tape over the compartment.
6. Search the recall list. Type the product name or brand into cpsc.gov. Light-up novelties are recalled often.

Spare and used batteries count too. The poison center says to keep them out of sight and reach, and if you cannot recycle them, wrap them securely and throw them away where a child cannot find them.

What should you do if a child swallows a button battery?

Do not wait for symptoms. The CPSC and the poison center both say:

• Go to the nearest emergency room right away.
• Call the National Battery Ingestion Hotline at 800-498-8666 or Poison Help at 800-222-1222 for treatment advice.
• Do not make the child vomit.
• Bring the battery package or a matching battery if you can grab it quickly, so doctors know the type.

The poison center also describes giving honey to children over 12 months old on the way to the hospital, in set amounts, if the battery was swallowed within the past 12 hours. Follow the hotline's instructions on that, and never delay the trip for it. Saving both numbers in your phone today takes ten seconds.

Bottom line

Button batteries are among the most dangerous small things in a home with young kids. Products made after 23 October 2023 should have a secured battery door. Anything older, and some cheap novelty items, may not. Give every secondhand gadget the one-thumb test before it goes near a child, keep spare and used coin cells out of reach, and look up recalls before you buy.

If you shop for used gear, our 5 dates to check on anything secondhand is a good companion to this one. You can browse what is on offer at Buy Now or Auctions, and the FAQ answers questions about how the shop works.

Know a parent stocking up on Halloween glow toys this week? Send them this before the party.