An electronic vapour provision device comprising a battery assembly and a vaporiser, wherein the battery assembly comprises a power cell and a computer. The vaporiser is releasably connectable to the battery assembly and the computer comprises a computer processor and a memory； wherein the computer is configured to detect whether the vaporiser is connected to the battery assembly without use of the electronic vapour provision device by a user； and to substantially remain in a sleep mode until the vaporiser is connected to the battery assembly. The computer is configured to wake from sleep mode after a predetermined sleep time to determine whether the vaporiser is connected to the battery assembly； and to re&minus；enter sleep mode if a vaporiser is not connected to the battery assembly. This enables the computer to determine whether the vaporiser is connected and configure the device as required.
