Recently, Tang Yongbing, a researcher at the Functional Thin Film Materials Research Center of the Institute of Advanced Technology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, and his research team have successfully developed a calcium-based dual-ion battery based on a dual-carbon structure. Related Research Results A Novel Calcium-Ion Battery Based on Dual-Carbon Configuration with High Working Voltage and Long-Cycling Life has been published online in Advanced Science (Advance Science, 2018, DOI: 10.1002/advs.201701082).
Since the successful commercialization of lithium-ion batteries in 1991, they have been widely used in various electronic devices, new energy vehicles, and energy storage. However, due to limited and uneven distribution of lithium resources, and the difficulty in recycling lithium-ion batteries, lithium has been produced. The cost of ion batteries is gradually increasing, which is difficult to meet the requirements of low-cost and environmentally-friendly recycling for large-scale energy storage in the future. Compared with lithium ions, calcium has similar physical and chemical properties and is rich in reserves. In addition, calcium The ion band has 2 charges, and the standard hydrogen electrode potential is -2.886V, which is close to lithium, which makes the calcium ion battery expected to be the next generation of new high-efficiency and environmentally-friendly energy storage device. However, in the traditional organic electrolyte, the surface of the metal calcium is prone to passivation. The calcium ions can not be reversibly deposited like lithium ions, and the development of calcium ion battery materials is difficult. Most calcium ion batteries can only be reversibly charged and discharged at high temperatures, resulting in slow development of calcium ion batteries.
In view of this, Tang Yongbing and his team members Wu Shi, Zhang Fan and others successfully developed a calcium-type dual-ion battery based on double carbon structure. The battery material is cheap and easy to obtain and environmentally friendly, using expanded graphite as a positive electrode material, PF 6-The anion can be reversibly embedded/extracted in its lamellar structure; using mesophase carbon microspheres as the negative electrode material, Ca 2+It can be reversibly embedded/extracted in its lamellar structure. The electrolyte uses a carbonate-based electrolyte based on calcium hexafluorophosphate as an electrolyte. Studies have shown that the calcium-type dual-ion battery can achieve reversible charge and discharge at room temperature, and performance Excellent electrochemical performance: The average working voltage is up to 4.6V, and the capacity retention rate is 94% after 300 cycles at 1C. This new calcium ion battery structure design opens up new ideas for the research of calcium ion batteries, and is also based on The study of multivalent metal ion batteries provides a reference.
The research was funded by the National Natural Science Foundation of China, the Guangdong Science and Technology Plan Project, and the Shenzhen Science and Technology Plan Project.
(a) Schematic diagram of charge and discharge mechanism of calcium-type dual ion battery based on double carbon structure; (b) charge and discharge curve; (c) dQ/dV curve.
