[Leica] more info on the M9 3rd party battery mystery

[kyle cassidy on the LUG]

So …. I’d bought four 3rd party batteries for the M9, all of which had more mAh’s than the 1860 that the OEM batteries have — “how cool I thought, they’ll last longer” — this is the case with 3rd party batteries of larger capacities that I have for Nikon & Panasonic cameras.

Imagine my surprise when the non-OEM M9 batteries showed to be dead in the camera after a few minutes or hours, imagine my greater surprise when I tested these dead batteries that couldn’t power up the camera with a volt-meter and found them nearly fully charged.

Based on input from a lugger, I tried draining the batteries completely, then recharging them to 100% and putting them in the the camera — where they worked perfectly and lasted longer than the OEM battery. 

No idea why this happens, well, I have some idea, but it’s all vague. Thoughts from electrical engineers?

(additional news: someone just right now told me that the m9 sometimes erroneously reads “the battery state readout” and that pressing “set” when you get the “battery dead” message will recalibrate this)

(additional additional news: someone else just forwarded me a thread from preview where people are reporting the exact same problem with OEM batteries. The plot thickens.)