Researchers at the Hong Kong University of Science and Technology have developed a high-capacity, long-life lithium-sulfur battery that uses a dual-function cathode substrate for Li-S batteries. The cathode substrate is composed of activated cotton fibers decorated with uniformly distributed boron carbide nanoparticles. (B4C) made. -ACF).
Long-term cycling test results of Li-S battery with S/B4C-ACF electrode at 1 C. Zhang et al.
… Li-S batteries have attracted much attention due to their super-high theoretical energy density (2567 Wh kg-1), cost-effectiveness and environmental protection. … However, before this technology can be commercialized, there are several challenging issues that need to be solved.
For example, S8's insulator properties and discharge products (Li2S) lead to low active material utilization and poor reaction kinetics. The shuttle effect produced by the soluble long-chain lithium polysulfide (LiPS) in the organic electrolyte leads to low Coulombic efficiency and serious capacity degradation. To make matters worse, the relatively large volume expansion of sulfur after lithiation easily leads to continuous changes in the volume of the cathode during the discharge/charge process, and eventually crushes the entire cathode structure.
……Here, we use a catalyst-assisted manufacturing method to manufacture a new type of positive substrate made of activated cotton fiber (B4C-ACF) decorated with uniform B4C nanoparticles for Li-S batteries. ——Zhang et al.
The B4C-ACF substrate has an ultra-high Bruno-Emmett-Teller (BET) specific surface area of 224.51 m2 g -1 and abundant mesopores. B4C nanoparticles not only serve as powerful chemical anchor sites to capture polysulfides, but also provide abundant active sites for effective sulfur conversion reactions. The ACF network provides a fast electronic path for the conversion reaction and acts as a current collector.
In a paper in Power Magazine, the researchers reported that their lithium-sulfur battery can provide an initial capacity of up to 1415 mAh g-1 at 0.1 C, and an ultra-high reversible capacity of 928 mAh g-1 at 3 C. , The area sulfur load is 3.0 mg cm-2.
The B4C-ACF substrate enables the Li-S battery to stably cycle for 500 times, and maintain a capacity of up to 988 mAh gư-1 at 0.5 C, which is four times that of a pure ACF substrate battery (192 mAh) gư-1 after 500 cycles).
In addition, the battery based on the B4C-ACF substrate can operate stably for 3,000 cycles, with a coulombic efficiency as high as 99.24%, and the capacity decay rate per cycle at 1 C is as low as 0.012%. The researchers said that these results prove that the B4C-ACF substrate has great potential in realizing the mass production of advanced Li-S batteries.
Ruihan Zhang, Cheng Chi, Maochun Wu, Ke Liu, Tianshou Zhao (2020) "A long-life lithium-sulfur battery with a cathode made of activated cotton fibers decorated with well-distributed B4C nanoparticles," Power Magazine, No. 451 Volume, doi: 10.1016/j.jpowsour.2020.227751
Posted on January 21, 2020 in Battery, Lithium Sulfur | Permalink | Comments (2)
It is great to know whether there are known and visible obstacles in the commercialization of this type of battery (for example, in the case of new graphene-based battery solutions that have emerged in recent years, large-scale production of graphene)
Posted by soltesza | January 21, 2020 at 04:06 AM
It can run stably...A lot of things are "ok".
Posted by: SJC_1 | January 21, 2020 at 05:12 PM
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