Interactions between mullite saggar refractories and Li-ion battery cathode materials during calcination

Comparison of interactions of MgO‐based refractories with Li‐ion battery cathode materials during calcination

“…The presence of both Al 2 O 3 and SiO 2 results in the most severe corrosion of cordierite (2MgO·2Al 2 O 3 ·5SiO 2 ) among these three MgO‐based refractories. Although mullite (3Al 2 O 3 ·2SiO 2 ) contains both Al 2 O 3 and SiO 2 , residual mullite peaks can be observed, whereas no cordierite is found in the cylinders after firing at 1000 and 1100°C. This comparison reveals that mullite is less attacked than cordierite by LNCM materials.…”

“…Cylinder samples (diameter = 36 mm, height = ~ 8 mm, weight = 25 g) consisting of MgO‐based refractory materials and Li(Ni x Co y Mn z )O 2 (LNCM) precursor mixtures were used for the lab scale corrosion tests. The detailed information for preparing cylinders consisting of MgO‐based refractory materials and LNCM precursor has been described in previous work . The LNCM precursor is supplied by a LNCM material producer (Do‐Fluoride New Energy Tech Co., Ltd, Jiaozuo, China) containing commercially available Li 2 CO 3 (≥99.0 wt% purity) and (Ni 0.5 Co 0.2 Mn 0.3 )(OH) 2 (≥99.0 wt% purity) powders in a weight ratio of 30:70.…”

“…Mullite (3Al 2 O 3 ·2SiO 2 ) has been commonly used as refractory saggers due to their low cost, sufficient thermal shock resistance, and chemical stability in air atmosphere at elevated temperatures . To identify and understand the occurring interfacial reactions of mullite refractory saggers with LNCM materials, post‐mortem analyses combined with refractory‐LCNM precursor cylinder tests in lab‐scale were performed in the previous study . It is found that Li 2 O‐derived phases, ie, LiAlSiO 4 , LiAlSi 2 O 6 , and LiAlO 2 , were generated from the interfacial reactions and result in cracking and spalling of mullite‐based saggers .…”

“…To identify and understand the occurring interfacial reactions of mullite refractory saggers with LNCM materials, post‐mortem analyses combined with refractory‐LCNM precursor cylinder tests in lab‐scale were performed in the previous study . It is found that Li 2 O‐derived phases, ie, LiAlSiO 4 , LiAlSi 2 O 6 , and LiAlO 2 , were generated from the interfacial reactions and result in cracking and spalling of mullite‐based saggers . Once the thickness and strength of the remaining refractory sagger have become critical for a safe operation during calcination, a costly replacement of the refractory sagger is deemed necessary.…”

“…It is of great interest that the degradation mechanisms of refractory materials are identified and understood for the selection of long lifespan refractory materials for the calcination of LNCM materials. Therefore, interaction behaviors between refractory materials and LNCM materials were compared in this work via the refractory‐LCNM precursor cylinder tests in lab‐scale, which have been proven to be an effective method in studying the degradation of refractory saggers contacting with LNCM materials …”