Liquid sump for heater

An electronic cigarette comprising a main body and a capsule, wherein the main body comprises a power supply unit, electrical circuitry, and a capsule seating configured to connect with the capsule, the capsule comprising:

• a first end configured to engage with an electronic cigarette device and a second end arranged as a mouthpiece having a vapour outlet, the capsule further comprising:
• a storage reservoir configured to store a liquid to be vaporised;
• a vaporising chamber arranged to receive liquid received from the storage reservoir;
• a heating element housed within the vaporising chamber, the heating element comprising a capillary element configured to vaporise the received liquid and generate a vapour;
• a vapour flow path extending between the vaporising chamber and the mouthpiece to allow the generated vapour to flow from the vaporising chamber to the mouthpiece;
• a buffer reservoir in fluid communication with the storage reservoir to allow liquid to flow from the storage reservoir to the buffer reservoir, wherein the buffer reservoir has a fluid capacity that is smaller than a fluid capacity of the storage reservoir;
• and
• wherein the capillary element is located outside of the buffer reservoir and arranged to contact liquid received in the buffer reservoir.