Not just catching up fire or exploding as you sleep next to them, dozens of dangerous gases are being produced by the batteries found in billions of consumer devices like smartphones and tablets, scientists have warned.
The team has identified more than 100 toxic gases released by lithium-ion batteries, including carbon monoxide, which can cause strong irritations to the skin, eyes and nasal passages and harm the wider environment.
According to the researchers from the Institute of NBC Defence and Tsinghua University in China, many people may be unaware of the dangers of overheating, damaging or using a disreputable charger for their rechargeable devices.
"Nowadays, lithium-ion batteries are being actively promoted by many governments all over the world. The lithium-ion battery is used by millions of families, so it is imperative that the general public understand the risks behind this energy source," said Jie Sun, lead author and professor at the Institute of NBC Defence.
The dangers of exploding batteries have led manufacturers to recall millions of devices.
Dell recalled four million laptops in 2006 and millions of Samsung Galaxy Note 7 devices were recalled in 2016 after reports of battery fires. But the threats posed by toxic gas emissions and the source of these emissions are not well understood.
Sun and her colleagues identified several factors that can cause an increase in the concentration of the toxic gases emitted. For example, a fully charged battery will release more toxic gases than a battery with 50 per cent charge.
The chemicals contained in the batteries and their capacity to release charge also affected the concentrations and types of toxic gases released.
"Dangerous substances, in particular carbon monoxide, have the potential to cause serious harm within a short period of time if they leak inside a small, sealed environment, such as the interior of a car or an airplane compartment," Sun noted in the study published in the journal Nano Energy.
Almost 20,000 lithium-ion batteries were heated to the point of combustion in the study, causing most devices to explode and all to emit a range of toxic gases.
The researchers now plan to develop this detection technique to improve the safety of lithium-ion batteries so they can be used to power the electric vehicles of the future safely.