A Dual-Carbon Battery Based on Potassium-Ion Electrolyte

5 years ago

A Dual-Carbon Battery Based on Potassium-Ion Electrolyte

Yongbing Tang, Fan Zhang, Nanzhong Wu, Bifa Ji

Although potassium-ion batteries (KIBs) have been considered to be promising alternatives to conventional lithium-ion batteries due to large abundance and low cost of potassium resources, their development still stays at the infancy stage due to the lack of appropriate cathode and anode materials with reversible potassium insertion/extraction as well as good rate and cycling performance. Herein, a novel dual-carbon battery based on a potassium-ion electrolyte (named as K-DCB), utilizing expanded graphite as cathode material and mesocarbon microbead as anode material is developed. The working mechanism of the K-DCB is investigated, which is further demonstrated to deliver a high reversible capacity of 61 mA h g-1 at a current density of 1C over a voltage window of 3.0–5.2 V, as well as good cycling performance with negligible capacity decay after 100 cycles. Moreover, the high working voltage with medium discharge voltage of 4.5 V also enables the K-DCB to meet the requirement of some high-voltage devices. With the merits of environmental friendliness, low cost and high energy density, the K-DCB shows attractive potential for future energy storage application. A novel dual-carbon battery based on potassium-ion electrolyte (K-DCB) is developed using expanded graphite as cathode and mesocarbon microbead as anode. The K-DCB presents a reversible capacity of 61 mA h g−1 at 1 C, and exhibits excellent cycling performance. This battery works stably over a voltage window of 3.0–5.2 V with medium discharge voltage of 4.5 V, the highest value among the reported potassium-ion batteries.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/aenm.201700920