Practical Realization of O3-Type NaNi0.5Mn0.3Co0.2O2 Cathodes for Sodium-Ion Batteries

In this work, we report the practical realization of 3.6 V Sodium-ion coin and multi-electrode pouch-type cells using O3-type layered NaNi0.5Mn0.3Co0.2O2 cathodes and dextrose derived hard carbon anodes in one-unit cell. The manuscript provides a thorough study of NaNi0.5Mn0.3Co0.2O2 cathodes along with hard carbon anodes and its practical difficulty in the development of Sodium-ion cells. NaNi0.5Mn0.3Co0.2O2 cathodes deliver an initial discharge capacity of similar to 136 mAhg(-1) with a moderate capacity retention of 87 mAhg-1 at 0.1C rate after 200 cycles. Similarly, the hard carbon anodes show a reversible capacity of about 280 mAhg(-1) at C/10 rate. The diffusion coefficient of Sodium-ion calculated is in the order of 10(-11) -10(-12) cm(2)s(-1) suggesting good reversibility, capacity retention and C-rate performance of the cathode. Further, no change in peak voltage in dQ/dV plots, XRD patterns, and CVs dictates the crystalline phase stability of NaNi0.5Mn0.3Co0.2O2 during cycling. NaNi0.5Mn0.3Co0.2O2 retains good structural stability during long cycling and decreased interlayer transition metal ion migration. Engineering aspects for assembling and testing O3-Type NaNi0.5Mn0.3Co0.2O2-hard carbon in the full cell is also investigated thoroughly. Herein, we have taken the research output and challenges from the coin-type cell and applied further to develop single and multi-electrode pouch type-cell of various configurations. (C) 2020 The Electrochemical Society (ECS). Published on behalf of ECS by IOP Publishing Limited.