Planning on powering that next über-low-power board of yours from a measly CR2032 coin cell? All the power to you (ug), but you might find this helpful app note from TI worth reading to understand exactly what the limitations of coin cells are, I.e.:
When designing a small wireless sensor node to be powered by the popular CR2032 coin cell, some sources claim there is a 15mA “limit” and that drawing more current is not possible or will “damage” the battery. This may give the impression that at 15mA everything works perfectly and battery capacity is great, while at 16mA nothing works. There is little public information available to explain why such a limit exists (if it indeed does exist), and little information explaining why 15mA would be a “magic number”.
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