How safe — or unsafe — are smartphone batteries?

Repairing stuff has been in the news a lot lately with all the development related to Right to Repair and companies like Apple and Samsung encouraging users to take on repairs to make their devices last longer.

This has prompted questions from people who are drawn to the idea of carrying out their own repairs, but who are worried about turning the battery into a fireball on their kitchen table.

So, how safe are smartphone batteries? Or, let’s turn that around, how much can they handle? 

Well, I decided to find out.

NOTE: Do not try this at home. My purpose here is to show you that if you do damage a battery, the outcome is likely not as bad as you might think.

As you can see in the video above, a battery — in this case, a fully-charged battery — can take a lot of abuse. I bent, punctured, then bent it some more. The battery did get warm and puff up a bit, but didn’t explode or catch fire.

Afterward, off camera, I put more holes into it, but it didn’t spark into life.

Don’t let this make you complacent though. I’ve seen batteries — especially the higher-capacity batteries found in power banks — burst into flames or a shower of sparks after getting damaged.

Also: 7 warning signs that your smartphone or laptop battery could explode

But if you’re sensible, and take sensible precautions, you should be safe.

And talking of sensible precautions, here are some safety warnings to bear in mind if you’re planning to replace a smartphone battery:

• If in doubt, don’t do it!
• Have the proper tools, such as the iFixit Pro Tech Toolkit.
• Buy a quality replacement battery.
• Don’t mess around with batteries in the midst of flammable things. 
• Have a fire extinguisher nearby, and a metal dish filled with sand to store the battery.
• Gloves and safety glasses are highly recommended.
• Don’t deliberately pierce or damage a battery.
• Dispose of the used battery safely. Don’t throw it into the trash!