Why does…? #13: Why do old phone batteries swell up?
As a lithium-ion battery ages (heat, overcharging, damage) its electrolyte breaks down into gas that puffs up the pouch; a swollen battery must be replaced, never pressed or punctured.
Why is this phone's back popping open? 📱💥
Inside is a lithium-ion battery sealed in a soft pouch.
With age, heat and overcharging, the liquid inside (the electrolyte) slowly breaks down — and makes gas.
The gas can't escape, so the pouch puffs up like a pillow and pushes the back open.
Swollen battery? What should you do?
❌ Don't press it flat
❌ Don't keep charging it
✅ Stop using it and recycle it safely (a repair shop or e-waste point)
Read the voiceover (transcript)
- Why is this phone's back popping open?
- Inside: a lithium battery, sealed in a pouch.
- With age and heat, its liquid breaks down into gas!
- The gas can't escape, so the pouch puffs up like a pillow.
- Swollen battery? What should you do?
- Stop using it, never press it, and recycle it safely!
- Next: how does an induction cooktop work? Follow for more!
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