I'm designing a portable temperature logger that I would like to be able to measure temperature within my home oven. I plan on designing a mechanical enclosure to hopefully protect the design from 'frying'. Essentially I will be insulating it and I don't intend on keeping it in there any longer than it has to be.
I was looking at small coin cells to power my design (it's very important that this design be very flat, only a few mm's tall). I was looking at a couple CR2032 coin cells that assumed to be appropriate for my current draw and required capacity. However, I have noticed that they are only rated to 70C.
Now my oven will likely be getting up to 250C, so obviously it will be important to have good insulation because the battery will be outside of its rated temperature.
But I'm curious, is this safe? Assuming my design isn't exposed to an open flame, could the battery explode? I've been hearing a lot in the news of exploding batteries. I assume the battery would eventually stop working if it got too hot, but could the battery explode? Or would it likely just stop working? Again, I'm looking at a small CR2032 coin cell. I'm primarily curious in the case my insulation fails.
Best Answer
So, first of all, CR2032 is a Lithium Battery type, so, yes, overheat it and it has a good chance of exploding/combusting.
I'd really just go and use some cable to get the sensor into your oven, and keep the battery on the outside. Less trouble, more reliability, less isolation that could fail.