Synthesis, Characterization, and Thermal Stability of Li[Ni1/3Mn1/3Co1/3−z(MnMg)z/2]O2

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• 作者：Wenbin Luo ; Xinhai Li ; J.R. Dahn
• 刊名：Chemistry of Materials
• 出版年：2010
• 出版时间：September 14, 2010
• 年：2010
• 卷：22
• 期：17
• 页码：5065-5073
• 全文大小：1024K
• 年卷期：v.22,no.17(September 14, 2010)
• ISSN：1520-5002

文摘

LiNi_1/3Mn_1/3Co_1/3−z(MnMg)_z/2O₂ (0 ≤ z ≤ 1/3) samples were prepared from hydroxide precursors. The hydroxide precursors were heated with Li₂CO₃ at 900 °C for 3 h to prepare the oxides. The XRD results show single phase LiNi_1/3Mn_1/3Co_1/3−z(MnMg)_z/2O₂ samples can be prepared for 0 ≤ z ≤ 1/3. Rietveld refinements of XRD data show that when Mn and Mg substitute for Co in NMC there is an increase in the amount of transition metal in the Li layer. Electrochemical studies of the LiNi_1/3Mn_1/3Co_1/3−z(MnMg)_z/2O₂ (0≤ z ≤ 1/3) samples were used to measure the rate of capacity reduction with z, found to be about −250 (mAh/g)/(z = 1) charging to 4.3 V and −150 (mA h/g)/(z = 1) charging to 4.6 V. The impact of Mn and Mg cosubstitution on the thermal stability of charged LiNi_1/3Mn_1/3Co_1/3−z(MnMg)_z/2O₂ (0 ≤ z ≤ 1/3) samples in electrolyte was studied using accelerating rate calorimetry. The thermal stability of LiNi_1/3Mn_1/3Co_1/3−z(MnMg)_z/2O₂ is independent of z for the samples studied.