Ding Xuan, Zhang Fan, Ji Bifa, Liu Yi, Li Jinrui, Lee Chun-Sing, Tang Yongbing
Functional Thin Films Research Center , Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences , Shenzhen 518055 , China.
Nano Science and Technology Institute , University of Science and Technology of China , Suzhou 215123 , China.
ACS Appl Mater Interfaces. 2018 Dec 12;10(49):42294-42300. doi: 10.1021/acsami.8b15193. Epub 2018 Nov 29.
Potassium-ion batteries (KIBs) are regarded as a potential alternative battery technology to conventional lithium-ion batteries owing to their low potential, natural abundance, and the low cost of potassium. However, sluggish reaction kinetic of the much larger K ions leads to low rate capability and poor cycling performance of KIBs, restricting KIB's practical applications. Herein, we propose a novel full battery called a potassium dual-ion hybrid battery (KDHB) by employing an absorption-type hierarchical porous carbon as the anode material and an anion intercalation-type expanded graphite (EG) as the cathode material. Owing to the hybrid mechanism of the battery and capacitive reaction, the KDHB exhibits superior rate performance with a high capacity of 82 mA h g even at a high current density of 3 A g with negligible capacity decay. Moreover, the KDHB exhibits excellent cycling performance with 74.2% capacity retention after 2000 cycles at 1 A g, which is so far the best performance of the reported KDIBs.
钾离子电池（KIBs）因其低电位、天然丰度以及钾的低成本，被视为传统锂离子电池潜在的替代电池技术。然而，大得多的钾离子缓慢的反应动力学导致KIBs的倍率性能低和循环性能差，限制了KIBs的实际应用。在此，我们通过采用吸收型分级多孔碳作为负极材料和阴离子插层型膨胀石墨（EG）作为正极材料，提出了一种新型全电池，称为钾双离子混合电池（KDHB）。由于该电池的混合机制和电容反应，KDHB即使在3 A g的高电流密度下也表现出优异的倍率性能，具有82 mA h g的高容量，且容量衰减可忽略不计。此外，KDHB在1 A g下经过2000次循环后容量保持率为74.2%，展现出优异的循环性能，这是迄今为止报道的钾双离子电池（KDIBs）的最佳性能。
