Lithium-ion batteries are indispensable in our daily life. We use them all the time in cell phones, laptops and even electric vehicles to store energy. Most of us have probably experienced the anxiety when our cell phone battery is running low and wish that the battery can be charged within minutes.

The research team led by Dr Denis Yu, Associate Professor in the School of Energy and Environment, has developed a novel dual-graphite battery system, where more than 90% of the capacity can be charged within 3 min. Their findings have been published in the scientific journal Advanced Functional Materials, titled “Ultrafast Charging and Stable Cycling Dual-Ion Batteries Enabled via an Artificial Cathode–Electrolyte Interface” (https://onlinelibrary.wiley.com/doi/abs/10.1002/adfm.202102360).

“Dual-ion batteries use both cations and anions inside the electrolyte to store and release energy. They can react faster than conventional lithium-ion batteries and also store more energy than conventional supercapacitors.” said Dr. Yu. “This type of batteries is suitable for applications where both high power and high energy are required.”

The team discovers that a salt additive (LiDFOB) can form a thin robust layer on the surface of the graphite active material. This protective layer suppresses electrolyte decomposition and side reactions, allowing fast transport of anions into and out of the graphite layers within minutes. The graphite electrode can also be cycled more than 6000 times with small capacity loss.