A Novel Surface Treatment Method and New Insight into Discharge Voltage Deterioration for High‐Performance 0.4Li2MnO3–0.6LiNi1/3Co1/3Mn1/3O2 Cathode Materials. Issue 16 (23rd June 2014)

• Record Type: Journal Article
• Authors: Oh, Pilgun; Ko, Minseong; Myeong, Seungjun; Kim, Youngsik; Cho, Jaephil
• Is Part Of: Advanced energy materials. Volume 4:Issue 16(2014)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2014-06-23
• Subjects: Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.201400631
• Languages: English
• ISSNs: 1614-6832

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The Li‐rich cathode materials have been considered as one of the most promising cathodes for high energy Li‐ion batteries. However, realization of these materials for use in Li‐ion batteries is currently limited by their intrinsic problems. To overcome this barrier, a new surface treatment concept is proposed in which a hybrid surface layer composed of a reduced graphene oxide (rGO) coating and a chemically activated layer is created. A few layers of GO are first coated on the surface of the Li‐rich cathode material, followed by a hydrazine treatment to produce the reducing agent of GO and the chemical activator of the Li₂MnO₃ phase. Compared to previous studies, this surface treatment provides substantially improved electrochemical performance in terms of initial Coulombic effiency and retention of discharge voltage. As a result, the surface‐treated 0.4Li­₂MnO_3–0.6LiNi_1/3Co_1/3Mn_1/3O₂ exhibits a high capacity efficiency of 99.5% during the first cycle a the discharge capacity of 250 mAh g⁻¹ (2.0–4.6 V under 0.1C), 94.6% discharge voltage retention during 100 cycles (1C) and the superior capacity retention of 60% at 12C at 24 °C.</p> </abstract>