Canon EOS 90D Instruction Manual page 739

Checking the Remaining Capacity of a Registered Battery
You can check the remaining capacity of batteries not currently in use, as
well as their last date of use.
(1)
(2)
Deletion of Battery Information
1
Select [Delete info.].
Follow step 2 on = 525 to select [Delete info.].

2
Select the battery information to delete.
[ X ] will appear.

3
Press the <L> button.
Select [OK] on the confi rmation dialog.

(3)
Look for the serial number.
Refer to the battery's serial number label

and look for the battery's serial number
(1) on the battery history screen.
You can check the respective battery's
approximate remaining capacity (2) and
the date when it was last used (3).
Checking the Battery Information
527