As for removing the battery to run only on powersupply: Some devices need so much power that the charger can't deliver it fast enough and the device just shuts

As for removing the battery to run only on powersupply: Some devices need so much power that the charger can't deliver it fast enough and the device just shuts down. This is when the battery is supposed to take over to provide enough power for the temporary surge. This is more a question for laptops I guess since surfpads and phones are optimised for battery only usage.