Introducing ion-transport-regulating nanochannels to lithium-sulfur batteries
Introducing ion-transport-regulating nanochannels to lithium-sulfur batteries
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将离子传输调节纳米通道引入锂硫电池
DOI：
10.1016/j.nanoen.2017.01.025
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发表时间：
2017-03-01
期刊：
影响因子：
17.6
通讯作者：
Dou, Shi Xue
中科院分区：
文献类型：
--
作者：
Pan, Yuede;Zhou, Yahong;Dou, Shi Xue
离子通道能够促进某些特定离子的转运，同时阻断其他分子或离子种类穿过生物细胞膜和细胞内细胞器的能力，在生物体维持基本生理活动中起着重要作用。该特征在可再充电锂电池中是高度期望的，因为一些电极（例如硫阴极）的电化学性能由于活性材料相关的阴离子溶解到电解质中以及锂离子的缓慢传输而大大减弱。在这里，受自然界的启发，将具有带负电荷的纳米通道的聚合物膜应用于硫-碳阴极，以克服锂-硫电池的循环稳定性和倍率性能差。该聚合物膜具有带负电荷的纳米通道，其宽度尺寸（约100 nm）为100 nm。2nm），因此能够通过促进锂离子的传输和拒绝多硫化物阴离子的迁移来调节离子传输。在0.2C和1C下循环100次后，比容量分别保持在1105和838 mAh·g（-1）的高水平。在18 C的高倍率下，经250次循环后，比容量保持率达91%，比容量保持率达612 mAh g（-1）。
The ability of ion channels to facilitate the transport of some specific ions and meanwhile block other molecular or ionic species across the membranes of biological cells and intracellular organelles plays an important role in biological bodies for maintaining basic physiological activities. This feature is highly desirable in rechargeable lithium batteries because the electrochemical performances of some electrodes, such as sulfur cathodes, are greatly weakened by the dissolution of active material related anions into the electrolyte and the slow transport of lithium ions. Here, inspired by nature, a polymer membrane with negatively-charged nanochannels is applied to a sulfur-carbon cathode to overcome the poor cycling stability and rate capability of the lithium-sulfur battery. The polymer membrane possesses negatively charged nanochannels with a width dimension (ca. 2 nm) comparable to the Debye length, therefore is capable of regulating the ion transport by facilitating the transport of lithium ions and rejecting the migration of polysulfide anions. At 0.2 C and 1 C, the specific capacities keep at high levels of 1105 and 838 mA h g(-1) after 100 cycles, respectively. Furthermore, at a high rate of 18 C, a high specific capacity of 612 mA h g(-1) is retained over 250 cycles, with a high capacity retention of 91%.