Lithium-ion batteries are known to go up in flames these days. 2016 was the year of terror for Samsung. There were emergency landings just because a Galaxy Note 7 was inside a plane. You can even find news about exploding iPhone 7 units, if you have the time.
Warning! Dangerous object!
So you might as well wonder why the humble lithium-ion battery can become such dangerous. For starters, electrolytes are highly flammable components of a battery. A separator between the negative and the positive ions is created to avoid ignition that causes explosion. In case of Galaxy Note 7 fiasco, several units had this separator malfunctioning.
Scientists devised a new plan for putting the fire out before it goes out of control. The idea works similar to a fire extinguisher. The system get activated once the device gets too hot. Think of it as the final safety net in case the separator between the ions fails to function.
However, lithium-ion batteries are known for high energy density and the slow rate of discharge. These traits made this type of battery appealing to the market. Adding a flame retardant alone to the electrolyte renders the battery less efficient, hence handicapping what made lithium-ion batteries easy to use in the first place.
Scientist will solve the problem
Scientists from Stanford University tried some experiments. They invented a sheet of tiny fibers containing flame retardants. This sheet can be inserted between electrodes while not sacrificing the battery’s performance. That’s the researchers report in a nutshell as published in Science Advances last January.
These microscopic fibers consist of plastic shells that have fire retardants inside. To make a comparison, the shell encapsulates the fire retardant under normal conditions. In this way, electrolyte’s efficiency will not be sacrificed. However, when the battery heats too much, the plastic sheets melt to release the flame retardant, like fire sprinklers, only in microscopic level.
Specifically, the extinguishers are spilled into the electrolyte when the battery’s temperature exceeds 160 degrees Celsius. What’s even more amazing with their experiment was the fire was squelched 0.4 seconds after the ignition. Talk about some fast activation.
“Using our ‘smart’ separators, battery’s electrochemical performance will not be affected by the flame retardant under normal conditions.” according to the senior author Yi Cui, a materials scientist at Stanford University in California. “However, once there is a potential thermal runaway, the flame retardant will be activated and nip the fire or explosion in the bud.”
“We believe our safe separator should find broad applications, considering that more and more fires and explosions of lithium-ion batteries have been reported recently.” he added.
The study is still in its infancy but this is a great leap nonetheless. If this succeeds beyond laboratory testing phase, it’s going to be revolutionary. We had the invention of airbags in our cars, and the literal fire sprinklers in hotel rooms, so why not this? Who knows what will happen if this goes out in the market and how many lives will be saved.
What can you say about this invention? Voice your thoughts in the comments!