Lithium ion battery is necessary in today‘s social mobile electronic equipment power supply, by the positive and negative, the diaphragm, such as electrolyte composition, its key performance indicators (such as performance and cycle life) is determined by the electrochemical performance of anode materials. LiFePO4 is recognized as the anode material, in order to improve its electrochemical properties, long-term commitment to people, shortening the distance between the lithium ion diffusion or reduce the size of the [010] direction. Recent studies show that the electrode is composed of a large number of particles, in the process of its electrochemical performance mainly depends on the charge and discharge at the same time to participate in the electrochemical reaction of particles (activated particles) accounted for the proportion of the total number of particles. Therefore, how to obtain a high activation population proportion of LiFePO4 is the key problem of the research of the anode material.
Aiming at this problem, the Chinese academy of sciences institute of metal material science in shenyang national laboratory of high performance ceramics (joint) research xiao-hui wang group on the basis of previous research (j. Phys. Chem. C 114:16806 (2010); Phys. Chem. Chem. Phys., 14:2669 (2012); CrystEngCommun 16:10112 (2014)), by creating acid synthesis of the extreme lack of water environment, for the first time in the world were 12 nm thick [100] orientation LiFePO4 ultrathin nano film. Voltage hysteresis experimental results show that the electrodes made of this material has by far the smallest gap voltage (the voltage gap), constant potential titration clearance test results show that the electrode has high activation rate and conversion rate, these results suggest that the [100] orientation LiFePO4 ultrathin nano piece of electrode with a high proportion of activated particles. Therefore, the electrode has excellent performance and cycle life. In 10 C (60 minutes) / 10 = 6 minutes to charge and discharge rate, the cycle can keep 90% of the initial capacity after 1000 times. In 20 C to charge and discharge rate, the capacity is still can be amounted to 72% of theoretical capacity. The work for the future to further improve the lithium ion battery performance ratio provide new method and Angle, which can not only by reducing the scale of the [010] direction to shorten the lithium ion diffusion distance, at the same time also can control the size of the [100] direction to increase the activation of lithium ion battery population proportion to improve the lithium ion battery performance ratio. The results published in the January 13 issue of Nano Letters (16:795-799) of the magazine.
The work is "the introduction of outstanding scholars" project by metal and support cas youth council for the promotion of innovation.