Synthesis of Commercial Li(Ni0.33Co0.33Mn0.33)O2 Cathodic material viaSol-Gel Method

To date, batteries play an important role in storage energy industry. Cathodic materials due to existence lithium ions in own structures for ithiation/delithiation should be have high specific capacity, high current rate capability and long life time [1]. Commercial NCM with Li(Ni0.33Co0.33Mn0.33)O2 chemical formulae due to high specific capacity of 170 mAh/g in comparison to 165 mAh/g for LFP and 145 mAh/g for LCO as a popular cathodic material attracts many researches attention. Moreover, intercalation of lithium ions into NCM layered structure cause to prevent induced stress due to lithiation and delithiation [2].ExperimentIn order to NCM-111 synthesis via sol-gel method, acetate precursors of Ni, Co and Mn were weighted to stoichiometry ratio, and were vigorously stirred after adding to 100 mL deionized water. Afterward, lithium precursor and 1 M complexing citric acid were added to solution to form NCM complex. Finally, fixed pH solution was drying at 80 ˚C and was calcined at 450 ˚C and 700˚C respectively for 5 h and 10 h for phase stability and removal polymeric impurities.Results and discussionIn this study, the effect of calcination temperature to synthesize pure Li(Ni0.33Co0.33Mn0.33)O2 was investigated. The achieved XRD patterns of sample well shows to form NCM compound with Li(Ni0.33Co0.33Mn0.33)O2 stoichiometry that completely consistent with 98-011-06256 reference code. Comparison of both pattern together clearly shows that increasing calcination temperature caused to decline of peaks width and rising of peaks intensity, which showing grain growth and dislocation formation. FESEM micrograph of sample after 10 h calcination at 700 ˚C was shown in figure 2. The existence of porosity into 20 μm particle makes it possible for lithium ion insertion/extraction with high rate capability. Moreover, figure 2-b demonstrate 20 μm particles involve lower particles, which ranging of 300 nm to 1 μm.ConclusionIn summary, we have shown that Li(Ni0.33Co0.33Mn0.33)O2 successfully synthesized via sol-gel method and the existence of porosity in its microstructure makes it possible for lithium ioninsertion/extraction with high rate capability.

کلیدواژه ها:

NCM ، cathode materials ، sol-gel