Do watches need batteries to operate?

Watches, like many other products around us, have evolved dramatically with the rise of technology and the advancements in the scientific research fields that have to do with electronics.

Electronics have led to the creation of watches that use electric circuits to move the watch needles. These circuits need a battery to operate. For that reason, we see a lot of watches that contain batteries inside them.

However do all watches really need batteries to operate?

Some watches do not require a battery to operate. The most famous non-battery watches are called the automatic watches. Automatic watches do not contain any circuits that require a battery power to perform and they use a traditional method to power the movement of the watch needles.

But how can a watch operate without using a battery?

According to the law of conservation of energy, energy can neither be created nor destroyed. Energy can only be transformed from one form to another.

With that said, you always need to consume energy in the watch in order to be able to produce enough energy to move the watch needles as accurately as possible.

Many watches use batteries to transform chemical energy to the electrical energy needed to operate the circuits inside the watch and move the needles.

The more interesting question is, how does a watch without a battery move its needles in an accurate way?

Automatic watches take advantage of the kinetic energy generated when the watch moves. They have what is called a mainspring.

Automatic watches store energy inside the mainspring. The mainspring provides enough energy to move the gears inside the watch and that in turn moves the needles.

The question is, how does the mainspring gain its energy.

There are 2 ways in which the mainspring inside a non-battery watch gains energy.

  • The owner of the watch has to wind the watch manually every short period of time.
  • The watch automatically winds itself while the owner is wearing the watch.

Usually, the mechanical non-battery watches have a crown on their side that you can rotate to restore the energy inside the mainspring of the watch.

You’ll need to wind the watch yourself every period of time to make sure that it functions properly. So in other words, you are the battery of your watch. You are transforming the energy that you used to rotate the crown to the mainspring of your watch.

There is another method of providing the mainspring of your watch with energy and that is the automatic winding.

Automatic watches contain an oscillating weight that moves when you move the watch, and the movement of the oscillating weight provides energy for the mainspring.

So in simpler words, the auto-winding watches use the natural movements of the wearer in order to generate energy for the mainspring. The watch will gain energy whenever you move while wearing it.

However, this requires that you keep wearing your watch a lot. If you leave your watch untouched for a long time, it will not be able to recharge and it’ll stop working until you wind it again.

Are automatic watches less accurate?

Yes, automatic watches are usually less accurate than watches that use batteries. However, the accuracy in automatic watches is still extremely high, and usually the error is not noticeable. It’s just a few seconds difference during a day.

With that said, if you’re only concerned about the non-battery watches’ accuracy, then you don’t need to worry about it at all. Just make sure that you get a good automatic watch and you’re good to go.

Are automatic watches more expensive?

Usually, automatic watches are more expensive than the rest because they require more work to assemble. Precise engineering is needed when making an automatic watch, and crafting an automatic watch usually requires more work.

To summarize

There are watches that do not use batteries to operate properly. Automatic watches are one of them. These watches use the kinetic energy generated by their owner to power themselves and they are accurate enough for them to be useful.