An international team of researchers publish details of an engineered electrode material that could boost further research in developing advance electrical batteries.
With the rise of global warming and the knowledge of the dangers gaseous emissions have on the environment, the use of electric vehicles has been gaining popularity. However, these electric vehicles have yet to be proven to be as efficient as vehicles that utilise a conventional combustion engine. Long charging time required to “refuel” an electric vehicle has been a significant point of deterrence in using it as an environmentally-friendlier option.
While a typical SUV with a combustion engine could travel 300 miles (approx. 490 kilometres) with a five-minute refuel, a state-of-the-art electric vehicle takes about one hour to store enough energy to travel the same distance. The technology for a high-capacity lithium-ion battery that charges quickly and operates efficiently maybe an unrealized goal – with the recent study published in Science, researchers are one step closer.
"The combination of high energy, high rate, and long cycle life is the holy grail of battery research, which is determined by one of the key components of the battery: the electrode materials," said Ji Hengxing, professor at the University of Science and Technology of China (USTC).
"We aim to search for an electrode material that can make a dent in performance metrics from laboratory research and can hold the promise to stand with the industrial production techniques and requirements."
According to the study’s first author, Jin Hongchang from USTC, efficient and effective lithium-ion transfer is of great importance as energy flows within the battery through electrochemical reactions in electrodes.
A commonly over looked material for the use in electrodes, black phosphorus, was used by the researchers in combination with graphite, stabilising the chemical bonds between the materials to prevent any issue and inefficiencies in lithium-ion transfer.
The team of researchers also applied a thin polymer gel coating to the electrode, strengthening the lithium-ion transport path. This key modification helped to solve the issue of electrolytes breaking down into less conductive pieces and building up on the surface of the electrode, inhibiting lithium-ion transfer into the electrode material.
"The composite anode material restored 80 percent of its full capacity in less than 10 minutes and shows a 2000-cycle operation life at room temperature, which was measured at conditions compatible with the industrial fabrication processes," said co-first author Xin Sen, professor of the Institute of Chemistry Chinese Academy of Sciences.
"If scalable production can be achieved, this material may provide an alternative, updated graphite anode, and move us toward a Lithium-ion battery with energy density of more than 350 watts-hour per kilogram and fast-charging capability. Successful projection of the above parameters onto the electric vehicle will significantly raise its competitiveness against the fuel cars."
As described by Professor Xin Sen, with an energy capacity of 350 watts-hour per kilogram, the battery would potentially travel 600 miles (approx. 970 kilometres) after a single charge.
Professor Ji also shared that with this novel technology, the researchers will be pursuing further fundamental scientific questions of the lithium-ion charging-discharging process, looking at industry-level ways to scale production of this composite material.
"We will investigate engineering materials of rationally selected structure, but with consideration for price and practicality to achieve an attractive performance," Professor Ji said.