LAUSR

Abstract To understand the effects of the calcining pressure gradient on the structure, morphology, and electrochemical properties of LiNi0.8Co0.15Al0.05O2 (NCA), Ni0.8Co0.15Al0.05 (OH)2 precursors prepared using a coprecipitation method are calcined under gradually increasing oxygen pressures to fabricate different cathode materials. The results of characterization using X-ray diffraction and scanning electron microscopy suggest that the material (NCA-0.6) possesses the best comprehensive properties when the calcining oxygen pressure is 0.6 MPa, at which the values of I(003)/I(104) and D50 are appropriately 1.727 and 11.06 μm, respectively. A cell assembled with NCA-0.6 delivers a discharge specific capacity of 143.3 mAh g−1 with a capacity retention ratio of 80.3% after 100 cycles at 1.0 C. Moreover, it presents a lower resistance of 327.5 Ω and redox peak difference of 0.11 V compared to the values of 1953.2 Ω and 0.26 V for NCA-0.1. These results suggest that appropriately enhancing the calcining oxygen pressure is an effective way to improve the cycle stability of NCA materials without any modified method.