You can disable led indication for battery full via executing (root not required):
mcetool --disable-led-pattern=PatternBatteryFull
To undo, execute:
mcetool --enable-led-pattern=PatternBatteryFull
The tool can be installed via (root required):
devel-su
pkcon refresh
pkcon install mce-tools
Another alternative is to override default led patterns via installing custom mce config files. The default values and short explanation about format can be found from /etc/mce/20hybris-led.ini.
Note: There is no need to edit existing files. Creating a new file - with higher two digit number in front - can be used to override values defined in already existing files. That is both easier to undo and your modifications will not be lost on the next upgrade.
For example: (without affecting other uses for led) when battery gets full, led blinks red for one minute (root required)
printf "[LEDPatternHybris]\nPatternBatteryFull=40;4;60;500;2500;ff0000\n" > /etc/mce/90-battery-full-hack.ini
systemctl restart mce
And to undo:
rm /etc/mce/90-battery-full-hack.ini
systemctl restart mce