PROVIDENCE, R.I. [Brown University] — When it comes to making batteries that last longer, a team of researchers including engineers at Brown University and Idaho National Laboratory believes the key might be in how things get clean — specifically how soap works in this process.
Take handwashing, for instance. When someone washes their hands with soap, the soap forms structures called micelles that trap and remove grease, dirt and germs when flushed with water. The soap does this because it acts as a bridge between the water and what is being cleaned away, by binding them and wrapping them into those micelle structures.
In conducting a new study published in Nature Materials, researchers noticed that a similar process plays out in what has become one of the most promising substances for designing longer lasting lithium batteries — a new type of electrolyte called a localized high-concentration electrolyte. This new understanding of how this process works, they posit in the paper, might be the missing piece to fully kicking the door open in this emerging sector of technology.
“The big picture is that we want to improve and increase the energy density for batteries, meaning how much energy they store per cycle and how many cycles the battery lasts,” said Yue Qi, a professor at Brown’s School of Engineering. “To do this, materials inside of traditional batteries need to be replaced to make long-life batteries that store more energy a reality — think batteries that can power a phone for a week or more, or electric vehicles that go for 500 miles.”
Scientists have been actively working to transition to batteries made from lithium metal because they have a much higher energy storage capacity than today’s lithium-ion batteries. The holdup is traditional electrolytes, which are integral because they allow an electrical charge to pass between a battery’s two terminals, sparking the electrochemical reaction needed to convert stored chemical energy to electric energy. Traditional electrolytes for lithium-ion batteries, which are essentially made of low-concentration salt dissolved in a liquid solvent, don’t do this effectively in metal-based batteries.