# mouse
#MousePercent=`ioreg -c AppleDeviceManagementHIDEventService | grep 'Magic Mouse' -A6 | grep BatteryPercent | sed 's/[a-z,A-Z, ,|,\",=]//g' | tail -1 | awk '{print $1}'`
MousePercent=`ioreg -n "BNBMouseDevice" | grep BatteryPercent | sed 's/[a-z,A-Z, ,|,\",=]//g' | tail -1 | awk '{print $1}'`
helped me on the latest macOS.