Nankai scholars develop "respirable" batteries -Lithium - Ion Battery Equipment
The rechargeable "metal air battery" takes light active metals such as Li, Na, Mg, Al, Zn as the negative electrode, and the air electrode composed of carbon, precious metals or transition metal oxides as the positive electrode. When discharging, it obtains oxygen from the air, and then releases oxygen when charging, so it is known as the "breathable" battery. The metal air battery has an ultra-high theoretical energy density, and the electrode active material is cheap and easy to get. In particular, the use of CO2 as the active material to replace oxygen to generate electric energy means that the battery system is expected to provide a stable energy source in areas where CO2 is enriched, such as animal and human gathering places, automobile exhaust, coal-fired power generation exhaust, Mars exploration and other fields. Therefore, it is promising as the "next generation green high specific energy battery". However, the actual performance of metal air battery is limited by the reaction kinetics of oxygen reduction/oxygen evolution of air electrode, so it is necessary to use electric catalyst to improve the reaction efficiency. Platinum group precious metals and their alloys are excellent electrocatalysts in catalytic activity and stability.(Lithium - Ion Battery Equipment)
Spinel type oxides are a kind of important functional materials, which are widely used in the fields of electricity, magnetism, catalysis, energy and so on. They are also potential electrocatalysts for metal air batteries. This kind of compound is usually prepared by the traditional solid phase sintering method, which requires high temperature and long time heating to overcome the diffusion resistance and reaction energy barrier, which consumes energy and takes time. Although the crystallization performance of the obtained product is good, the composition is easy to segregate, the composition and morphology are difficult to control, the particle size is large, the specific surface area is small, and the reaction activity is low, limiting its application in electrocatalysis, energy storage, etc. Chen Jun's team put forward and established a new method of "reduction oxidation conversion crystallization" to solve the problem that the traditional high-temperature solid state method is difficult to achieve the synthesis of spinel at room temperature, developed the synthesis methodology of inorganic solid materials, and prepared highly active oxygen reduction/precipitation electrocatalytic spinel nanocrystals at room temperature; Spinel material is used to replace Pt electrode and is applied to rechargeable metal lithium/zinc air battery. The energy density of zinc air battery reaches 335Wh/kg, which is the highest energy density metal air battery with the longest cycle life at present and is expected to become the safe power battery of the next generation of electric vehicles.
It is understood that the new strategy for the preparation of spinel nanocrystals proposed by the project is conducive to green preparation, new energy utilization, energy conservation and emission reduction. The developed spinel nanocrystals can replace platinum based catalytic materials, providing a new idea for the development of efficient, cheap, new large capacity, long-life metal air batteries. Relevant research achievements were published in NatureChem. (2011, 3, 79; 2012, 4962), NatureCommun. (2015, 67345), Angel. Chem. Int. Ed. (2015, 544338) and other academic journals, and were invited to publish reviews in Chem. Soc. Rev. (2015, 44699); 4 technologies with independent intellectual property rights have been granted patent protection, and 2 patents have been transformed.