posted on 2017-11-27, 00:00authored byJiaxin Zheng, Wenjun Deng, Zongxiang Hu, Zengqing Zhuo, Fusheng Liu, Haibiao Chen, Yuan Lin, Wanli Yang, Khalil Amine, Rui Li, Jun Lu, Feng Pan
Using
ab initio calculations combined with experimental confirmation,
we design an asymmetric intercalation battery using K2NiFeII(CN)6 as the cathode, commercial graphite as the
anode, and an organic electrolyte containing mixed lithium and potassium
salts. It works by reversible K-ion intercalation at the cathode side
and reversible Li-ion intercalation at the anode side simultaneously.
The π-electron coordination environment in K2NiFeII(CN)6 ensures the preferred reversible intercalation
of the K-ion, and the small ionic radius ensures the preferred reversible
intercalation of the Li-ion in graphite. It also shows a high working
voltage (∼3.6 V) and an ultralong cycling life with no capacity
fading even after 5000 cycles.