Four fire engines and around 25 firefighters tackled a fire at a warehouse on Hallowfield Way in Mitcham.
Part of the warehouse and a small part of a plant digger were damaged by the fire. Five tonnes of household waste were also damaged by the fire. There were no reports of any injuries.
The fire is believed to have been accidental and caused by batteries igniting flammable materials.
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.
“Batteries can also present a fire risk if they’re short circuited, submerged in water or damaged, so it’s really important to protect them and store them carefully.
“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 was called at 1028 and the incident was over for firefighters at 1116. Crews from Mitcham, Wimbledon, Norbury and Tooting Fire Stations attended the scene.