Why does a battery explode?

Question

Physics

The battery of the iPhone 3GS exploded and swelled. The phone is beyond repair, why is this happening? It is clear that the apparatus is many years old, but explain why?

Answer 1

There are many factors, here are a few:

• You have installed a low-quality battery (fake or defective)
• You're taking too long to charge your phone's battery
• Water has entered the battery contacts.
• There was a serious malfunction in your phone, which led to incorrect voltage

Answer 2

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