Lithium-ion batteries are critical for both EVs and advanced hybrids. Li-ion offers a low weight, a long battery life, and a decent power to price ratio. Until now, lithium-ion battery packs had to have some sort of advanced electronic controller to limit overcharging which would greatly reduced the life of the battery, or destroy it altogether.
Two researchers at the Argonne National Laboratory have discovered that adding less than a gram of a molecule they created can effectively control a lithium ion's battery voltage from increasing outside of the safe operating range. The molecule, acts as the expensive electronic controller and can help reduce the temperature of the battery and keep it from overheating and self destructing.
The molecule is added to the electrolyte of the battery and is based on the elements of boron and fluorine. When added in very small amounts it can pick up electrons from the battery reducing or eliminating the cell charge from reaching volatile status.
What is the advantage of a lab made molecule versus an electronic controller? The molecule is much cheaper to produce. The controller can make up to 20% of the costs of the battery while the molecule will be considerably less. According to the researchers, this molecule could save $100 to $200 per battery.
An additional advantage is that the molecule is a simple addition to any battery. Unlike a controller which must be designed for each individual car, the molecule can simply be added to the electrolyte of an existing battery.
According to the researchers, the material is not easy to make, luckily it only needs to make up about 2 to 3 percent of the electrolytes total weight. Today, the molecule costs about $1,000 per kilogram to produce, but the target price is set at $100 per kilogram as production of larger batches get underway.
The researchers at Argonne have leased this breakthrough technology to battery producer EnerDel who in turn is using their Energy Department grant to increase the production of this new material.
Attempts to produce a molecule such as this have been made before, but there is one key difference. Previous attempts were successful at eliminating overcharging only one time before the molecule could no longer do its job, this new attempt is successful at eliminating overcharging more than 500 times.
Credit for this possible breakthrough product goes to Khalil Amine and Zonghai Chen at Argonne National Laboratory.