Battery drain while camera is off

[BruceW]

Has anyone experienced battery drain in the R5 (using battery grip) while the camera is off? I have the camera always in airplane mode as I don’t use Bluetooth or any wireless capabilities. I’ve recently had 2 occurrences where the camera was idle (turned off, not just asleep) for 3 days and when I went to turn it on, nothing happened. I removed batteries and tried to reposition them in case that was the issue, but still no response. When I replaced with my spare fully charged batteries, the camera started up. Right now I’m removing the battery pack when storing the camera for a few days.

 

[MikeZ]

I just picked-up my R5 a few weeks ago and I haven't noticed anything irregular with the battery, but to be honest I haven't looked closely. For what it's worth, most electronic devices siphon battery power to maintain the internal clock and calendar (along with probably a host of other things.) What I find odd, though, is the less than optimal charging recommendation found on page 25 of the user manual - "aim to charge it approx. 50% instead of fully charging it". So I guess Canon is recommending that we own at least a couple of batterries.

 

[Hutch]

One particular lens or all? Some folks found the 5D Mk IV tended to do that with the 100-400 Mk II attached for some reason.

 

[BruceW]

One particular lens or all? Some folks found the 5D Mk IV tended to do that with the 100-400 Mk II attached for some reason.

Yes - that’s the exact lens I had attached. Come to think of it, I haven‘t experienced this when I had other lenses attached.

 

[MikeZ]

Wow, so the 100-400 Mk II eats batteries. Good to know, but I wonder why?