Researchers from Stanford University developed a new lithium-ion battery that does not overheat. The innovative creation shuts down before its own temperature levels are increased, and then it restarts after the temperatures are safe to work. It was remarked that it could be used to prevent fires in electronic devices such as computers, navigation systems and hoverboards.
It was explained that common lithium-ion batteries can develop temperatures of approximately 300 degrees Fahrenheit (150 degrees Celsius), as a consequence, an electrolyte that holds charged particles between two electrodes can catch fire.
“People have tried different strategies to solve the problem of accidental fires in lithium-ion batteries. We’ve designed the first battery that can be shut down and revived over repeated heating and cooling cycles without compromising performance.” said Zhenan Bao, a professor of chemical engineering at Stanford, in a press release published in EurekaAlert!.
Previously, some researchers had developed methods in order to stop battery fires. However, after the batteries reached a certain amount of heat, they could not be recovered again. Co-author, professor Cui, said that a new approach was needed to design a battery that is not damaged by overheating.
Nanotechnology was determining for the development of the battery, as researchers coated spiky nickel microscopic particles with graphene (a layer of carbon), and put those particles in a film of elastic polyethylene, they explained.
“We attached the polyethylene film to one of the battery electrodes so that an electric current could flow through it. To conduct electricity, the spiky particles have to physically touch one another. But during thermal expansion, polyethylene stretches. That causes the particles to spread apart, making the film nonconductive so that electricity can no longer flow through the battery.” Said Zheng Chen, lead author of the study.
It appears that the battery can be configured to shut down at 50 C or 100 C, said professor Bao, who teaches chemistry. He added it depended on how many particles they put in, so it can be possible to design batteries according to the use that they are going to have and the material where it is going to be used.
In order to determine the effectiveness of the new battery, researchers used a hot-air gun to heat it. Results would appear to show that when the battery reaches high temperatures, it automatically shuts down and later starts again when the temperature levels have decreased.
Researchers added that when comparing this new battery with previous similar advances, their design is reliable, fast and can maintain a good performance while improving safety. Hopefully the new anti-fire method can be used to prevent several accidents that are registered each year as a consequence of battery overheating.
Last year, hoverboard scooters powered by lithium-ion batteries, alerted the country when it was demonstrated that some models caught fire or exploded. In Louisiana a house burnt down, when a charging hoverboard exploded five days before thanksgiving. The United States has even started an investigation to determine if the new transportation method is safe for users, and some retailers have removed specific hoverboard models from their stores.
Source: EurekaAlert