Can An Old Battery Cause a Fire?

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Keeping a stockpile of batteries for your flashlights and smoke detectors is one of the easiest ways to prepare for the event of an emergency. But what if your batteries are getting old and the fear sets in that they have the potential for more harm than good? 

Can old batteries cause fires?

Any battery has the potential to start a fire if a metal object happens to connect the terminals. When old batteries are improperly disposed of, they have the potential to start a fire if a piece of low-resistance material connects the positive and negative terminals.

Are our old batteries future fires instead of future life-lines? It can be difficult to tell what is safest for you and your loved ones, which is why we decided to put together this blog entry. We’ll look into how old batteries can actually affect you and your loved ones.

How Can an Old Battery Cause a Fire?

It’s not a far stretch for a battery to turn flammable. All a fire needs to start is a spark and a material to fuel it, therefore making old batteries a legitimate cause and worry for fires.

For instance, a 9-volt battery from a smoke detector can quickly cause a piece of thin metal, like steel wool, to heat up and burn if the piece is caught between the positive and negative ends of the terminals. 

In theory, old batteries are almost prime contenders for starting fires. Batteries are literally storage vessels for energy, and are therefore waiting to spark — even when too depleted to power a flashlight or a smoke detector. 

But how likely are old batteries to actually start fires? How should you dispose of them if you don’t want them to pose a danger?

Can I Test a Battery?

Yes, absolutely you can. Technology offers an inexperienced and accurate way to check the remaining power left in that older battery you just found. While it is not always recommended to mix new and old batteries, keeping a few older batteries with some power left might just come in handy. An inexpensive, accurate and great tool for the job is the D-FantiX Battery Tester.

Disposing of Old Batteries

Many people think that the sole purpose of battery disposal boxes and deposits are environmental in nature. This is not true! While recycling batteries is good for the environment, it’s also safe for the environment of your home!

Even low voltage batteries like AA and AAA have the potential to start fires when in contact with metal — like the material batteries are made out of. Even in a battery disposal container, there is the potential for a fire to break out. If the terminals are connected, heat and potentially even sparks are likely to follow.

A fire in a battery deposit container isn’t good for the environment because of the fumes it will release and because of the material wasted, but it’s far better than the alternative. This fire could happen in the wastebasket of your home! Especially if you have a metal wastebasket, a fire could break out and spread.

Think about it: would a fire be safer in a specially designed container, or in your home? Battery disposals are designed for the safety of the environment and the safety of your environment. We need to protect the plant and protect ourselves. 

If you are changing out your old batteries in your flashlights and smoke-detectors, bring them to a battery disposal at a hardware store, or look for your local battery drop-off. You already have safety in mind, why stop now?

Safe Battery Storage and Disposal at Home

Look around through the drawers in your house. Look in the drawer of your nightstand, and in those drawers that you don’t seem to use for anything. Maybe there are a couple of pennies and nickels, and maybe there are a couple of AA batteries that have been out of juice since you moved in.

As common as it is, loose batteries and loose change do not mix! Instead of rounding up all our change and bringing it into a Coinstar, we usually just leave it around for a rainy day and forget. Similarly, instead of rounding up all our used batteries and bringing them to a battery deposit or recycling area, we usually just say we will get to it later. 

What do you do when the batteries in your TV’s remote die? You might look at the trash, remember what you’ve heard about not throwing them out, then simply put them back on the table or put them in a nearby drawer. This is not safe!

Loose batteries and coins are something of ticking time bombs. As soon as the terminals are connected, the bomb is lit, and the fire could start at any moment. If you are away from your house when this happens, you won’t be around to prevent a little fire from turning into a big fire. It is essential to go around your home and locate all the loose batteries in order to properly dispose of them.

Can You Put Old Batteries in the Trash?

It is not recommended to throw out loose batteries. As mentioned, the preferred method of battery disposal is to bring them to your designated battery disposal or recycling center. This will ensure that no harm is caused by your old batteries and that as little material goes to waste as possible.

If you are unable to bring in your batteries, there is a very simple method for safer home disposal. 

  • Simply take your batteries, and carefully put electric tape on the ends of terminals. 
  • On cylindrical batteries, like AA and AAA, this means put them on either end. 
  • On 9V batteries, put the tape carefully between the terminals, then cover them so that neither terminal is visible. 

By covering the terminals of the batteries, you are essentially eliminating the risk of a fire starting by eliminating the risk of conductive material getting between them.

The home disposal method is more appropriate if you live in an area without access to a battery disposal or recycling area. Batteries can be disposed of in this way, but ideally, they will be properly recycled to guarantee safety.

A Cautionary Tale

About a decade ago, a man accidentally started a fire in his family’s home after he replaced the batteries from several smoke detectors. This is the worst fear of many people who are seeking to make their homes as safe as possible. All he wanted to do is protect the house from fires, and he ended up causing one instead. 

It’s true that you can never be too careful, but it’s easy to throw caution to the wind and undo all the good you’ve done. Where did he go wrong?

The man’s mistake was placing the three old 9V batteries he had just removed into one bag in order to later throw them out or recycle them. The battery terminals were not covered with electrical tape, and they were not separated at all. 

This was careless on his part, but it also highlights something very important about battery disposal: where are your old batteries stored before they are disposed of? Even if he was planning on bringing them into Home Depot for recycling, he still left them unprotected for the time being.

Be Prepared

Accidents happen when we least expect them. No matter what you plan on doing with your batteries, you have to keep in mind what could happen to them if you walk away or go and run an errand. In this case, the three batteries shorted against each other and provided enough heat to start a fire out of the battery material that spread throughout the house. 

Always hope for the best: like recycling the next day, and plan for the worst: like the possibility of something happening before then. Old batteries can cause fires, but they don’t have to.

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