A group of researchers led by Associate Prof. Ji Kemeng from Tianjin University reported to have developed a new electrochemical corrosion preparation technology that fabricates battery electrodes by just one step. Prof. Tan Yongwen’s group at Hunan University participated in the study. It is said to have provided new insights for the preparation and design of high-performance integrated electrodes toward practical applications.
In recent years, portable electronic devices and vehicles driven by new energy and clean energy have gained rapid development, calling for upgraded batteries to meet the market demand. Electrodes, as core parts of a battery, also require production breakthrough. The existing battery electrode fabrication involves nearly ten procedures such as gluing, batching, mixing, coating, roller pressing, baking, etc, and entails a variety of inactive materials like binders, conductive agents, and current collectors. Such complex processes increase the cost of battery preparation while reducing its actual energy density.
To address the above issues, the new technology puts a selected transition metal alloy into a neutral salt solution for electrochemically selective corrosion and potential-control oxidation. The whole electrode preparation process takes only one step and less than one hour, safe, green, and easy to achieve large-scale production.
The packing density of active components of the resultant cobalt-based integrated electrode is twice or three times higher than that of traditional graphite electrode. Since the volumetric capacity of a battery electrode is proportional to the packing density of its active materials, the charge-storage capacity of the newly developed electrode is five times that of graphite electrodes with the same volume. In addition, the integrated structure, together with the synergistic effect among its various components, makes its charging rate nearly ten times faster. It also possesses ultra-long cycling life that allows over 6,000 full charge-discharge cycles at 10 mA/cm2, which is twice to four times longer than that of commercial lithium batteries.
“We only need two raw materials to prepare our electrodes. One is sodium chloride namely edible salt, and the other is a metal alloy with a very mature industrial production technology. No extra additives and traditional current collectors are needed. Since both NaCl salt and metal alloy are common and inexpensive, the integrated electrode made by our strategy has a remarkable cost advantage. The simultaneously excellent energy-storage performance also makes it a very promising application,” said Ji Kemeng.
As Ji put it, this easy electrode fabrication strategy provides novel insights to the development of emerging integrated energy-storage electrodes. It opens up a new area for the high value-added use of industrial alloys, and can contribute to the industrialization of electrochemical corrosion technology.
The study result entitled Engineering Co-P Alloy Foil to a Well-Designed Integrated Electrode Toward High-Performance Electrochemical Energy Storage, was published on Advanced Materials, a top international academic journal on materials science.
By Gao Zuyi
Editor: Eva Yin
