Do magnets affect watch batteries?

Do Magnets Affect Watch Batteries? Here’s What Science Says

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You may have heard that there are certain devices that should not come into contact or close proximity to magnets. Older electronics like televisions, computer monitors, CRT displays, VCRs, cassette tapes, video tapes, and floppy disks were always advised not to be near magnetic forces; credit cards and ID cards as well can be damaged by magnets. But what about something less complex like a watch battery? Will a magnet have any impact on these?

It is possible for a watch battery to be affected by a magnet. This is only because many watch batteries have an iron coating. This will have the most negative effect if multiple batteries are near each other or still in a pack together, and the magnet causes them to group together in a certain way.

While it may not be likely for your watch batteries to be affected by magnets, let alone even come into contact with magnets, there are still some precautions to take when storing magnets or electronics to prevent any problems. Continuing on, we’ll address some of the more common questions surrounding the effects of magnets on various watches and their batteries.

Will a Magnet Drain a Watch Battery?

If watch batteries contain iron, ferrous metal, or metal that contains iron, they can be affected by magnets. This means that a magnet will be able to exert force on the batteries. But will simply keeping a magnet near these types of batteries completely drain them? The answer may surprise you.

A magnet is able to drain watch batteries. When multiple iron coated watch batteries are exposed to a magnetic force, the batteries can come into close proximity to each other. When the batteries make contact, they will begin to drain. This can happen with most types of household batteries.

Because the magnet itself is not the reason for the batteries becoming drained, it is good to be mindful of how you store your batteries. The batteries must make contact and create an electrical short to drain, so keeping loose batteries all in a junk drawer together may not be the ideal storage method. Seeing how so many people are leaving behind analog quartz or digital watches it is important to also consider this question regarding modern technology as well.

Are Magnets Bad for Smartwatch Batteries?

Magnets may not have any effect on the smartwatch itself, but the science says traditional watch batteries can be affected by magnets so what about the battery inside of a smartwatch? Can a magnetic force have a negative impact on one of these batteries?

Smartwatches generally use lithium ion batteries. Because lithium is an alkali metal it is not affected by magnetic charges. A smartwatch battery coming into direct contact with a magnet will have no effect on the battery. The battery’s charge will not be depleted and there will be no damage.

In addition to lithium ion batteries, most other types of household batteries will be unaffected by magnetic charges. While this is great news for smartwatch owners, another important question to be considered is the effect of a magnetic force on the watch itself. Will a magnetic charge damage or manipulate a watch in any way?

Do Magnets Mess Up Watches?

It is possible that you may find a magnet in close proximity to your watch at some point or another. If you care about your watch, you may be concerned whether a magnet could negatively affect your watch or somehow ruin its internal components. Is this something watch wearers should be conscious of?

Magnets can affect watches in several ways. The most obvious indication is that the watch may be running slow or fast in keeping time. But depending on the design of the watch, magnetism can cause internal parts to stick together and prevent the watch from running at all.

Fortunately, If this should happen, it is not the end of the watch. It will need to be demagnetized in order to function normally again. Most watchmakers and even some specialized jewelers may be up for this task and it should not take long or much money to demagnetize the watch. Keeping time poorly or failing to run is not necessarily a sign that your watch has been magnetized, so if it is having these issues, how can you tell if it is due to magnetization?

How Do I Know If My Watch is Magnetized?

If it is not immediately apparent that your watch is magnetized but you suspect that maybe it has been in contact with a magnetic force long enough to affect it. There are a couple of ways you can test your watch for magnetism to be certain.

If a watch is not keeping time, is regularly losing a minute or more or is seized, it can be tested for magnetism by holding a compass near it. If the needles of the compass seem to follow the watch as it is moved slightly, this indicates a magnetic charge.

In addition to this compass technique, there are also smartphone applications that can test for magnetism. Smartphones are capable of detecting magnetic fields with the right application and these are easy enough for anyone to use. A few good applications that can be used to monitor magnetic fields are:

  • Electromagnetic Detector: EMF Scanner for iOS– Easy to use and fun to play with, EMF Scanner is capable of picking up magnetic fields and radio frequency radiation in the immediate area. The EMF Scanner App can be downloaded for free in the Apple app store
  • Ultimate EMF Detector for Android– Simple and intuitive user experience. Can record data and the user is able to set alarms that will notify when EMF levels reach a user determined level. Ultimate EMF Detector can be downloaded for free in the Google Play Store
  • EMF Analyzer for Android- As with other EMF apps, this one utilizes what is called the tri-axis magnetic sensor in your phone, this sensor is how compass applications work as well. Like the previously listed apps, the EMF analyzer is capable of reading EMF in real time, displaying it with graphs, and can have audible alarms set when certain levels of EMF are reached. EMF Analyzer is available for free in the Google Play Store

Most of these applications have the same capabilities and should be able to give you noticeable enough readings to determine if your watch is magnetized. But what if your modern watch no longer has hands? You may be wondering if magnets can still have any effect on them. Can magnets affect smartwatches?

Are Magnets Bad for Smartwatches?

There are more and more people opting for smartwatches these days rather than quartz or digital timepieces. We should therefore, address the subject of magnets and how they affect modern timekeeping technology like smartwatches. Can magnets have a negative effect on smartwatches?

A typical magnet that you may find in any household cannot affect a smartwatch. In fact, the Apple Watch’s charger has a magnetic component and can be worn with a magnetic wrist band as well. Magnets are not a concern with many modern electronics like they used to be with older technology. 

In the older generation, primarily 90’s era and predecessors, storage hardware like floppy disks or old-fashioned hard drives used to rely on magnetic charges. The computers and electronics of that time used this technology. Contact with a magnetic field would wipe these forms of computer storage. This is partly where the idea of magnets harming electronics came from. Unless you are using an ultra high powered industrial electromagnet, your watch will be fine.

Can I Wear a Magnetic Bracelet with a Watch?

Magnetic bracelets are a modern trend, and even though they have a very minimal magnetic force, it is a common question whether wearing one on the same wrist as your watch is a good idea. Is it possible to wear both pieces together?

A magnetic bracelet should not be worn with a traditional or non-smartwatch. This is because even a low magnetic charge like the one given off by a bracelet will exert a force on components inside your watch. This will end up magnetizing the watch and cause it to lose time or seize. 

If you want to wear both your magnetic bracelet and a watch it is probably best that you wear them on different wrists or wear a smartwatch which will be unaffected by a magnet. 

Will Magnets Affect Any Batteries? 

We have covered watch batteries, lithium ion batteries and your everyday household batteries, and we know that magnets will not affect any of them. But obviously, there are so many more types of batteries than just these few. Will magnets affect any of them?

There is no evidence that magnetic fields can affect any of the following types of batteries,

  • Nickel – Cadmium Batteries.
  • Nickel – Metal Hydride Batteries.
  • Carbon Zinc Batteries. …
  • Silver Oxide Batteries. …
  • Zinc Air Batteries.
  • Deep Cycle
  • Wet Cell
  • Gel-cell

Even with a strong industrial “horseshoe” type magnet, it is unlikely that the batteries will show any sign of the magnet’s presence. With any possible questions about a magnet’s effect on batteries out of the way, there is still the question of how magnetic fields affect modern electronics. 

Will Magnets Affect Smartphones?

While we know that your smartphone’s battery will be unaffected by a magnetic field, there is still a question of a magnet affecting the phone itself. Is there any known effect that magnets can have on a smartphone?

A magnet can affect a smartphone if it is equipped with a magnetic sensor. Direct contact with a magnet could throw off the calibration of your phone’s magnetic sensor, and this will result in your compass not being accurate. Your phone’s screen and data will be undamaged by magnets though.

After covering all the bases on a magnet’s effect on smartphones, it is worth asking whether a smartphone itself is capable of affecting external devices like watches. After all, it does have a device in it to measure magnetic fields, and it also gives off a form of electromagnetic radiation. So can a smartphone affect a watch? 

Can Smartphones Magnetize a Watch?

As we have established that your phone has a magnetic sensor, some may be wondering if this characteristic is capable of having any impact on your watch? The answer might surprise you.

A smartphone is not capable of magnetizing a watch. However, the phone’s electromagnetic radiation can affect compass readings if in use near an external compass. It is also not recommended that smartphones come into close proximity to pacemakers or other implantable medical devices.

The type of electromagnetic radiation given off by smartphones is relatively low and harmless. Although it is worth noting that the FDA is the agency that recommends not having smartphones within close proximity to pacemakers and other implantable medical devices. These are sensitive pieces of equipment, and they provide too valuable of a function to take a chance on your phone’s EMF interfering with them.

Electromagnetic Radiation and Everyday Electronics

In our modern lives there are many devices in our surroundings that give off at least some type of magnetic field. In our electronics it is in the form of electromagnetic radiation. Speakers, motorized appliances like vacuum cleaners or the refrigerator, credit cards, and toys all utilize magnetics and thus will give off some level of magnetic field.

High levels of this radiation are harmful to both humans and our electronics. All modern technology that gives off any amount of Electromagnetic radiation has to be tested and checked by the FDA or FCC for approved, safe levels.

When it comes to simple household magnets, there is far less risk to our well being or our devices. As long as you keep magnets out of direct contact with your watches and properly store batteries, there is virtually no risk of a magnet interfering with them.