Recently, tangyongbing, a researcher at the functional film materials research center of the integration Institute of Shenzhen Institute of advanced technology, Chinese Academy of Sciences, and his research team successfully developed a metal aluminum foil cathode material with hollow interface structure and applied it to high-efficiency and low-cost dual ion batteries
Tang Yongbing said that this new structure effectively solves the problems of volume expansion and poor cycle performance of cheap metal cathode materials in the process of charging and discharging. Related research results, the ultra stable solid electrolyte layer formed by the design of foam paper interface and its application in high-efficiency dual ion batteries have been published in advanced materials, a top journal of materials science
with the rapid development of the market scale of portable electronic devices and electric vehicles, people have an increasingly urgent demand for secondary batteries with high energy density and low cost. At present, most commercial lithium-ion batteries use graphite negative pole materials, which are high-performance data experimental equipment in Colleges and universities, scientific research institutions, and factory and mine data research institutions. Its theoretical specific capacity is only 372 MAH g-1, and its compaction density is low, which limits the further improvement of the energy density of lithium-ion batteries
it is reported that through the alloying/dealloying reaction with lithium ions, cheap metal anodes usually have larger specific capacity and are expected to obtain higher energy density. "The theoretical specific capacity of aluminum is as high as 2234 MAH g-1 (li9al4), with abundant reserves and low prices." Tang Yongbing said, "however, the aluminum anode will produce a certain volume expansion during the battery reaction, which will affect the cycle stability of the battery."
based on the above considerations, Tang Yongbing and his team members Qin Panpan, Wang Meng, Li Na and others successfully developed a metal aluminum foil material with hollow interface microstructure. At the same time, the integrated design of active material and fluid collector was carried out, and it was successfully applied to a new type of high-efficiency, low-cost double ion secondary battery
the loosening of Tang contact will put all the equipment in a dangerous working state. Yong Bing said, "we use the structural design and the modified aluminum foil as the negative active material and collector at the same time, the expanded graphite as the positive pole, and the conventional electrolyte. Compared with the traditional lithium-ion battery, this new type of secondary energy storage battery has a higher working voltage (average discharge voltage - 4.2 V) At the same time, it significantly increases the proportion of active materials and energy density, significantly reduces manufacturing costs, and is environmentally friendly. "
in addition, the interface design of hollow microstructure makes the occurrence area of lithium aluminum alloy successfully limited in the hollow interface, so as to effectively alleviate the volume expansion of aluminum anode during the alloying process, and obtain a highly stable SEI membrane
the results show that the new battery can cycle 1500 cycles at half an hour charge and discharge rate (2C), and the capacity retention rate is as high as 99%; In addition, even when the power density is as high as 2113 wkg-1, the energy density of the battery is still 169 wh kg-1 (10c, charge and discharge time is 6 minutes), which is much higher than most commercial lithium-ion batteries
Tang Yongbing pointed out: "our research results have guiding significance for the development of low-cost metal cathode materials, and are expected to promote the development of high-energy, low-cost secondary batteries based on low-cost graphene to transform and upgrade the cathode of traditional industries."