I just bought 3 QM91 batteries and I am a bit worried of one of them.
All came empty and got a full recharge with my mono quickcharger.

Two of them display (when plugged full to the camera with the LCD monitor open) a lifetime of around 386 minutes, whereas one starts with only 260 minutes.

I know that the "normal lifetime" with LCD open should be around 4 hours with moderate zoom and almost permanent recording.


Do I have two very good performing batteries and one is just performing normally
or
is the Info Lithium not always that precise and the batterie will last longer
or
is one batterie performing less than it should?

All the three came in an untouched original Sony package from the same supplier.

I decharged the problem battery completely and charged it full again, but it still has the same amount of minutes when plugged, the others still start higher.

Any ideas?

I haven't charged mine recently, but IIRC they claim about 360 minutes initially. That time is constantly revised as used, and after a couple hours recording the estimate gets pretty accurate. When you discharged the suspect battery how long did it run the camera?

<<<-- Originally posted by Boyd Ostroff : (...) When you discharged the suspect battery how long did it run the camera? -->>>

no, I did it during the night, so no idea. I should give it a try.
I want to discharge the two others once as well, so that they have had at least one full cycle before coming to more extreme situations (specially situations -15°C, so less performance..), but I can do this later...

Maybe a long run with a "normal charger" could be an idea as well (through the camera)...