Four fire engines and around 25 firefighters were called to a house fire on Wells Way in Camberwell.
Part of the ground floor of a terraced house was damaged by fire. A man and a woman left the building before the Brigade arrived and were treated on scene by London Ambulance Service crews.
The fire was discovered by an occupant who could smell burning and upon investigation saw a fire in the ground floor kitchen. They then promptly left the building.
Sub Officer Andrew Ajimal, who was at the scene, said: "As we arrived, there was a substantial amount of thick, black smoke coming from the front window of the house and a large fire had developed at the back of the property.
"Crews quickly accessed the building and searched the property to confirm that nobody was inside.
"The majority of the damage was to the kitchen and crews worked really hard to bring the fire under control and prevent further damage.
"Road closures were in place whilst crews worked to make the scene safe."
The Brigade's Fire Investigators believe the fire was accidental and caused by the failure of a lithium-ion battery from an e-bike which had been left on charge.
The Brigade was called at 1100 and the fire was under control by 1201. Fire crews from New Cross, Dowgate, Brixton, Lambeth and Old Kent Road fire stations attended the scene.