p.1 #1 · Sony A7III - internal battery capacity loss
Lately the internal battery of my 5 year old A7III seems to have grown weaker. I usually always keep a rechargeable battery in my camera at 100-50% even if it is stored away for months. Maybe that is why I never had issues with the camera forgetting time and date before. But recently this message is popping up more frequently after a battery has been taken out, even if just briefly.
Just a few days ago, I took out the rechargeable battery only for 1 hour to charge it, so there was no battery inside the camera for an hour. Upon putting it back in, again time and date were lost. And this despite the battery having been inside over the whole night prior, so it should have charged the internal battery enough. I did a quick test by removing the battery just for 1 minute, but in that case time and date were still intact.
So that means the capacity of the internal battery must be very low, but it is not zero yet as apparently it can handle 1 or a few minutes without a rechargeable battery inside.
Anyway, is there anything that can be done about this? Is this expected behavior once the unit has reached a certain age?
p.1 #2 · Sony A7III - internal battery capacity loss
With the older A7's you had to charge the battery inside the camera occasionally, Not sure if it applies with the newer batteries, but not much to lose by trying it.
p.1 #3 · Sony A7III - internal battery capacity loss
This happened with my A7III. Ideally you should plug it in with the included cable (with a battery inside), this charges up the internal battery. Using it charges it too. I left mine for months without use and constantly got the date/time message.
Now I plug in my A9s every so often to avoid this problem. Really messes up the files when I have to set the date 3 times during a wedding.
p.1 #4 · Sony A7III - internal battery capacity loss
Thanks for the hint! I was not aware the internal battery is only charged by cable, thought it would also be charged as soon as you insert a rechargeable (main) battery - since as long as I have one inside the body, it seems I never have to deal with the date/time reset. But maybe this only 'holds' the charge/data and does not actively charge.
I have indeed not charged by cable in a long time since it is more convenient to just take the main battery out and charge it in a separate DC charger. Will make sure to test with cable-to-body-charging and hopefully that will restore the internal battery.
