Accelerated synthesis of Li(Ni0.8Co0.1Mn0.1)O2 cathode materials using flame-assisted spray pyrolysis and additives

Abstract

Nickel-rich cathode materials are promising in lithium-ion battery applications because of their high energy density and low material cost. Unfortunately, reducing the synthesis cost of nickel-rich cathode materials is challenging because of the time-consuming and energy-intensive calcination. Therefore, the current work aims to explore strategies for significantly reducing the calcination time of nickel-rich cathode material Li(Ni0.8Co0.1Mn0.1)O2 (NCM811). We used a flame-assisted spray pyrolysis method to synthesize samples with and without using low-cost urea as an additive. Both in situ thermal X-ray diffraction (XRD) and ex situ XRD revealed that urea addition weakened the sensitivity of crystallization and cation mixing to calcination conditions. As a result, with only 20 min of calcination at 875 °C and without any preheating and ramping steps, the NCM811 sample showed an ordered layered structure and comparable electrochemical performance to those with long-time calcination. Moreover, the current work demonstrated that the shortened post calcination was benefited from lithium-embedded particles that likely improved the uniformity of lithium distribution in as-synthesized powder. Therefore, carefully designing initial lithium distribution in particles prior to calcination could also be a useful strategy for other synthesis methods to shorten high-temperature calcination steps, leading to significant reductions in energy consumption and fabrication cost.