Premium
Excellent Cycling Stability and Superior Rate Capability of Na 3 V 2 (PO 4 ) 3 Cathodes Enabled by Nitrogen‐Doped Carbon Interpenetration for Sodium‐Ion Batteries
Author(s) -
Zhang Huang,
Hasa Ivana,
Qin Bingsheng,
Diemant Thomas,
Buchholz Daniel,
Behm R. Jürgen,
Passerini Stefano
Publication year - 2017
Publication title -
chemelectrochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.182
H-Index - 59
ISSN - 2196-0216
DOI - 10.1002/celc.201700053
Subject(s) - materials science , pyrolytic carbon , electrochemistry , carbon fibers , electrolyte , cathode , chemical engineering , graphene , carbon nanotube , sodium ion battery , doping , highly oriented pyrolytic graphite , conductivity , electrode , nanotechnology , graphite , composite number , composite material , chemistry , optoelectronics , faraday efficiency , pyrolysis , engineering
Polyanionic Na 3 V 2 (PO 4 ) 3 is considered as a promising cathode material for sodium‐ion batteries; however, it is limited by its poor electronic conductivity resulting in inferior rate capability and cycling stability. Herein, the rational design and synthesis of Na 3 V 2 (PO 4 ) 3 (NVP) particles embedded in various N‐doped carbon matrices, that is, nitrogen‐doped pyrolytic carbon (N−C), carbon nanotubes (N‐CNT), graphene nanosheets (N‐rGO), and Ketjen black nanospheres (N‐KB), are reported together with the structural investigation and electrochemical performance. It is evidenced that the N‐doped carbon coating efficiently improves the rate capability and cyclability with minor polarization of NVP materials as a result of enhanced electronic/ionic conductivities and facilitated charge transfer at the electrode−electrolyte interface. Particularly, the NVP nanograins dispersed in the N‐doped carbon nanotube matrix exhibit the best rate and cycling performance. When cycled at rates from 0.1 to 20 C, the discharge capacity decays only slightly from 114 to 100 mAh g −1 , offering outstanding high power capacity retention (88 %). Moreover, the material retains excellent capacity (92 %) upon long‐term cycling (3000 cycles) at extremely high rate of 50 C.