If the chassis of your laptop or smartphone gets thicker than usual, this is a sign that the battery is swollen. Li-ion batteries are packed into a dense black plastic coat. After some years, all batteries tend to leave some gas. If you search for repair options, they are all giving warnings:
You should never puncture a swollen laptop battery with a needle or any sharp object. Here's why:
Extreme Hazard:
- Fire/Explosion Risk: Lithium-ion batteries contain flammable electrolytes. Puncturing the casing can cause a short circuit, rapid thermal runaway, or ignition, leading to fires or even explosions.
- Toxic Fumes: Damaging the battery releases harmful chemicals (e.g., lithium compounds, hydrogen fluoride), which are dangerous to inhale.
- Physical Injury: Shrapnel
Safe Steps to Take:
- Stop Using the Device: Power it down and unplug it.
- Isolate the Battery: Place it in a fireproof container (e.g., metal bucket) away from flammable materials.
- Recycle Properly: Take it to an e-waste facility, electronics store (many offer recycling), or a hazardous waste disposal site.
Never:
- Attempt DIY repairs on swollen batteries.
- Charge or use a swollen battery.
However, the argumentation comes from FAA guidelines, that reports numerous cases of lithium battery fires in cargo or luggage. But this is usually triggered by strong forces, when physical power damage devices. So why not trying to repair a battery that has no evident damages and just got blown? I already planned to dispose it but I could not resist to give it a try.
I did a test with an HP laptop battery, that got swollen after five years. I punctuated it with a needle, very carefully where the three battery packs are covered. I did that outside with fresh air, wearing glasses to protect my eyes. I took care not to punctuate where wires are under the coat. After some gas (likely just CO2) emitted, I put a yellow patch on all three tiny holes. I will now put it back to the laptop, as that original battery pack was much more powerful (up to 8 hours with a Xubuntu OS) than the replacement I had put in just lasts for 2 hours. I certainly would have immediately stopped the experiment, if some fluid would have leaked.
Disclaimer: Repairing is on your own risk.