I'm wondering if it is okay to put a lithium ion battery directly next to a strong permanent magnet. Would this affect the functioning of the battery? Can it lead to early failure? In the worst case, can it lead to an internal short circuit?
In my setup, a small lithium ion battery (100-200mAh, similar to this link ) is used in the same device as a couple of neodymium magnets (N52 cubes, the strongest kind). The magnetic field at the surface of the magnets is up to 0.6-0.7 Tesla, which is really, really strong. Due to the mechanical design, the battery has to touch one or more magnets - there isn't any other good place to put it.
I can't think of a specific reason that wouldn't be okay, except that is a strong enough field that it could affect not just ferro- but also paramagnetic materials, and possibly affect chemical reactions so it might mess up the chemistry at the battery electrodes. Also it is a strong enough field that there isn't any everyday experience with it, hence I have no intuition about what to expect. The battery certainly doesn't come with a spec for "max allowed magnetic field".