采用化学共沉淀法,以硫酸盐为原料,氨水为络合剂,NaOH 为沉淀剂,制备得到颗粒均匀的镍钴锰氢氧化物Ni0．5 Co0．2 Mn0．3(OH)2前驱体,通过跟 Li2 CO3混合烧结后得到类球形的 LiNi0．5 Co0．2 Mn0．3 O2.采用热重分析(TG)、X射线衍射(XRD)、扫描电镜(SEM)对样品的结构、形貌、粒径分布进行表征,并利用恒流充放电测试对材料的电化学性能进行了分析.结果表明,在 pH 值＝11．5的条件下制备得到的前驱体,与 Li2CO3混合后,900℃下烧结后的正极材料,球形形貌规整,具有层状结构和优异的电化学性能,首次放电比容量达159 mAh/g,60次充放电循环后放电比容量为147．1 mAh/g,容量保持率为92％.可见所制备的 LiNi0．5 Co0．2 Mn0．3 O2材料具有高放电比容量、良好的循环性能和结构稳定性.
Spherical LiNi0.5 Co0.2 Mn0.3 O2 was prepared by calcining a stoichiometric mixture of Li2 CO3 and Ni0.5 Co0.2 Mn0.3 O2 (OH)2 precursor.The precursor was synthesized via a co-precipitation route with sulfate as raw materials,NH3 · H2 O as complexing agent and NaOH as precipitant.The crystalline structure,morphology were analyzed using X-ray diffraction (XRD),thermogravimetric analysis (TG),scanning electron microscope (SEM).And the effects of the pH value and calcination temperature on physical and electrochemical properties of the samples were deeply investigated.The cathode material with the well-ordered structural was obtained at the optimum synthetic conditions of the pH value 11.5 and the calcination temperature of 900 ℃.At the same time,the resultant powder of LiNi0.5 Co0.2 Mn0.3 O2 delivered a high discharge capacity of 159 mAh/g at 0.1 C, and excellent capacity retention of 92 % was retained after 60 cycles.
参考文献
| [1] | M. Armand;J.-M. Tarascon.Building better batteries[J].Nature,20087179(7179):652-657. |
| [2] | CHARGING UP THE FUTURE[J].Nature,20087221(7221):436-440. |
| [3] | Kang K;Meng YS;Breger J;Grey CP;Ceder G.Electrodes with high power and high capacity for rechargeable lithium batteries.[J].Science,20065763(5763):977-980. |
| [4] | Byoungwoo Kang;Gerbrand Ceder.Battery Materials For Ultrafast Charging And Discharging[J].Nature,20097235(7235):190-193. |
| [5] | Yan, Jianhua;Liu, Xingbo;Li, Bingyun.Recent progress in Li-rich layered oxides as cathode materials for Li-ion batteries[J].RSC Advances,2014108(108):63268-63284. |
| [6] | Tutomu Ohzuku;Yoshinari Makiumra.Layered Lithium Insertion Material of LiCo_1/3Ni_1/3O_2 for Lithium-Ion Batteries[J].Chemistry Letters,20017(7):642-643. |
| [7] | Ting Liu;Shi-Xi Zhao;Kezhen Wang;Ce-Wen Nan.CuO-coated Li[Ni_(0.5)Co_(0.2)Mn_(0.3)]O_2 cathode material with improved cycling performance at high rates[J].Electrochimica Acta,2012:605-611. |
| [8] | Yansong Bai;Xianyou Wang;Shunyi Yang.The effects of FePO_4-coating on high-voltage cycling stability and rate capability of Li[Ni_(0.5)Co_(0.2)Mn_(0.3)]O_2[J].Journal of Alloys and Compounds: An Interdisciplinary Journal of Materials Science and Solid-state Chemistry and Physics,2012:125-131. |
| [9] | Rougier A.;Delmas C.;Gravereau P..OPTIMIZATION OF THE COMPOSITION OF THE LI1-ZNI1+ZO2 ELECTRODE MATERIALS - STRUCTURAL, MAGNETIC, AND ELECTROCHEMICAL STUDIES[J].Journal of the Electrochemical Society,19964(4):1168-1175. |
| [10] | Longwei Liang;Ke Du;Zhongdong Peng;Yanbing Cao;Jianguo Duan;Jianbing Jiang;Guorong Hu.Co-precipitation synthesis of Ni_(0.6)Co_(0.2)Mn_(0.2)(OH)_2 precursor and characterization of LiNi_(0.6)Co_(0.2)Mn_(0.2)O_2 cathode material for secondary lithium batteries[J].Electrochimica Acta,2014:82-89. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%