A fully loaded battery, and yes it is the official Leica battery, is empty after 2 to 3 days with a camera that is not used and switched off.
So the moment I need the camera, the battery is always empty.
When the battery is full, the info display indeed reports the battery as being 100% charged.
When checking the battery charge every 12 hours, the charge indicator gradually drops to 90%, no lower, and there the battery gives up.
Charging the battery takes the full 3,5 hours, from which the green led flashes the first 2,5 hours. So the battery is as empty as it could be.
The Leica battery from my M8, that is working without any trouble in the M8, was also empty after 3 days in the M9. So the battery did not seem to be the problem.
The camera was sent to Solms with a description of this problem. It took 7 weeks to get the camera back just with a new battery, that was empty on arrival, no further repair had been done....
My direct fear became true, everything was as before, and a full battery was empty after 3 days in a non used camera with the top switch in the off position.
And now something strange happened. As a last minute decision, I took my empty battery M9 to an open air Opera, with the intention to have the battery loaded in my car with the Leica charger connected to the cigarette lighter, something I had never done before.
I had a diner in advance, so I left the battery connected to the charger for almost 3 hours.
When I started taking pictures, the charge indicator gave me 90% charge, so with my experience sofar, I thought that the battery was short before giving up, but it didn't.
The charge indicator went further down to 80 and 70%, values that I had never seen before.
In the days after, the charge indicator went all the way to 0% before the battery finally gave up after 3 days.
Then I charged again with the Leica charger connected to the mains, and everything was back as before starting at 100% and being empty after 3 days at 90%.
So in both cases of charging, the battery is empty after 3 days of non use, but having the battery charged over the mains shows a battery charge that goes from 100% to 90% before it gives up, and having charged the battery with my cars cigarette lighter shoes a charge that goes from 90% to 0%.