$ sudo udevadm monitor --udev --kernel --environment
monitor will print the received events for:
UDEV - the event which udev sends out after rule processing
KERNEL - the kernel uevent

KERNEL[1254931537.850913] change   /devices/LNXSYSTM:00/device:00/ACPI0003:00/power_supply/ACAD (power_supply)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/LNXSYSTM:00/device:00/ACPI0003:00/power_supply/ACAD
SUBSYSTEM=power_supply
POWER_SUPPLY_NAME=ACAD
POWER_SUPPLY_TYPE=Mains
POWER_SUPPLY_ONLINE=0
SEQNUM=1247

UDEV  [1254931537.896863] change   /devices/LNXSYSTM:00/device:00/ACPI0003:00/power_supply/ACAD (power_supply)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/LNXSYSTM:00/device:00/ACPI0003:00/power_supply/ACAD
SUBSYSTEM=power_supply
POWER_SUPPLY_NAME=ACAD
POWER_SUPPLY_TYPE=Mains
POWER_SUPPLY_ONLINE=0
SEQNUM=1247

KERNEL[1254931538.555417] change   /devices/LNXSYSTM:00/device:00/PNP0C0A:00/power_supply/BAT1 (power_supply)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/LNXSYSTM:00/device:00/PNP0C0A:00/power_supply/BAT1
SUBSYSTEM=power_supply
POWER_SUPPLY_NAME=BAT1
POWER_SUPPLY_TYPE=Battery
POWER_SUPPLY_STATUS=Full
POWER_SUPPLY_PRESENT=1
POWER_SUPPLY_TECHNOLOGY=Li-ion
POWER_SUPPLY_VOLTAGE_MIN_DESIGN=11100000
POWER_SUPPLY_VOLTAGE_NOW=12584000
POWER_SUPPLY_CURRENT_NOW=65163000
POWER_SUPPLY_CHARGE_FULL_DESIGN=2400000
POWER_SUPPLY_CHARGE_FULL=1111000
POWER_SUPPLY_CHARGE_NOW=1111000
POWER_SUPPLY_MODEL_NAME=UM08A72
POWER_SUPPLY_MANUFACTURER=SIMPLO
POWER_SUPPLY_SERIAL_NUMBER=1C8C
SEQNUM=1248

UDEV  [1254931538.563046] change   /devices/LNXSYSTM:00/device:00/PNP0C0A:00/power_supply/BAT1 (power_supply)
UDEV_LOG=3
ACTION=change
DEVPATH=/devices/LNXSYSTM:00/device:00/PNP0C0A:00/power_supply/BAT1
SUBSYSTEM=power_supply
POWER_SUPPLY_NAME=BAT1
POWER_SUPPLY_TYPE=Battery
POWER_SUPPLY_STATUS=Full
POWER_SUPPLY_PRESENT=1
POWER_SUPPLY_TECHNOLOGY=Li-ion
POWER_SUPPLY_VOLTAGE_MIN_DESIGN=11100000
POWER_SUPPLY_VOLTAGE_NOW=12584000
POWER_SUPPLY_CURRENT_NOW=65163000
POWER_SUPPLY_CHARGE_FULL_DESIGN=2400000
POWER_SUPPLY_CHARGE_FULL=1111000
POWER_SUPPLY_CHARGE_NOW=1111000
POWER_SUPPLY_MODEL_NAME=UM08A72
POWER_SUPPLY_MANUFACTURER=SIMPLO
POWER_SUPPLY_SERIAL_NUMBER=1C8C
SEQNUM=1248