Canon EOS R6 Mark II Mirrorless Camera with 24-105mm f/4-7.1 Lens - Manual (Page 945)

Checking the Remaining Capacity of a Registered Battery
Not in Use
You can check the remaining capacity of batteries not currently in use, as well as their last
date of use.
1.
Find the matching serial number.
On the battery history screen, find the battery serial number (1)
matching the serial number that the battery is labeled with.
You can check the respective battery's approximate remaining capacity
(2) and the date when it was last used (3).
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