Eight fire engines and around 60 firefighters were called to a fire at a flat on High Street in Feltham.
Half of a flat on an upper floor of a 11-storey residential building was damaged by fire. Three people were taken to hospital by London Ambulance Service as a precaution.
The fire is being treated as accidental and believed to have been caused by the failure of lithium-ion batteries for a power bank.
A London Fire Brigade spokesperson said: “Lithium batteries are susceptible to failure if incorrect chargers are used, so it’s important to always use the correct charger for the product and buy an official one from a reputable seller.
"You should unplug your charger when you have finished using it and we would advise not to leave it unattended or charging while people are asleep.
“Batteries can present a fire risk if they’re over-charged, short circuited, submerged in water or damaged, so it’s really important to protect them against being damaged too.
“Try to ensure they are not getting knocked around while in use or while being carried as this can increase the chance of damage to cells."
The Brigade received the first of six calls about the fire at 1842 and Control Officers mobilised crews from Feltham, Twickenham, Heston, Heathrow and surrounding fire stations to the scene. The fire was brought under control by 1932.