Released September 25, 2015. Model A1688/A1633. Repair of this device is similar to previous generations, requiring screwdrivers and prying tools. Available as GSM or CDMA / 16, 64, or 128 GB / Silver, Gold, Space Gray, or Rose Gold options.

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Battery odour, Headaches and polish smell ... Why?


I repair a lot of iPhones , ipads, but sometimes when i have to change a battery there's a sort of smell like polish remover coming from the battery .

The odour is not very annoying but when i sniff/breathe this odour, I feel a few headaches during 1 hour or less.

This odour can also be breathed sometimes on new batteries (Which are defective) or used batteries and sometimes also when taking off the batteries when it is broken

What this smell is composed of ?


Answered! View the answer I have this problem too

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The rechargeable Li-ion batteries that you work with contain several solvents. The two that have distinct odors are dimethyl carbonate (DMC) and diethyl carbonate (DEC). Most other solvents in Li-ion cells are odorless. So it's likely that you are smelling those solvents. DMC has an alcohol-like odor, while DEC has a weaker, milder ester-like odor (like nail polish). Neither are particularly toxic, and in fact dimethyl carbonate is classified as a 'green' solvent. DMC does metabolize into methanol, and if you get enough in your system, you'll get methanol poisoning. Headaches are one typical symptom of mild acute methanol toxicity. It's not likely that you are in serious danger, but long term exposure (over years) can cause health problems. Use good ventilation and you'll be fine.

Primary Li batteries are another story. Their odor probably comes from dimethoxyethane, which has a sharp chemical odor. It is classified as potentially toxic and on OSHA's watch list.

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Good ventilation is important for your repair bench. You may want to consider on of these. Not cheap but certainly worth it for your health.

This is an interesting resource for batteries:

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Thanks for your answer Minho but there's not information about the nailpolish odour and toxicity on your links ?! :(


You would have to be encountering an extreme number of devices with exploded batteries to have anything to worry about. The fact that you are saying you notice this on new batteries, yet no one else does, leads me to believe that this is an issue that you are creating on your own.

Buy a good fume extractor. If you are worried about your health, you should already have a fume extractor and good ventilation. No one here is going to be able to describe the nail polish remover because even though we have changed hundreds or thousands of bad batteries, we haven't encountered that on a large enough scale to be able to comment intelligently.

Buy a good fume extractor and don't put your face directly in the path of toxic fumes.


If you know the answer, post it like I did. If you don't, then just keep playing Fortnite. Annoying AF when you provide completely useless answers or just links that contain basically nothing.


The link in my comment was fine at the time I posted it...I can't control what the site owner does 12 months down the road. I have deleted it so that no one wastes any more time trying to find the info.

As for your snarky comment, keep it to yourself, it helps no one and doesn't contribute anything to this site. Your answer, on the other hand, is good and that's the only thing you should be concerning yourself with. Not everyone is an expert in Li-ion battery chemistry and an answer that "tries to help" is better than no answer at all.

@oldturkey03 @mayer


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Martin will be eternally grateful.
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