iron titanium

Positive spinel

As compared with the layered compounds LiCoO and LiNiO, spinel LiMnO to its price and environmental protection advantages as lithium ion battery cathode materials in the most development potential of A. However, spinel LiMnO in the battery charge and discharge cycle capacity loss attributed to organic solution decomposition and Jahn-Teller effect leads to structure damage.

At present people trying to modified spinel LiMnO material component, the material of Mn of the average oxidation state is maintained in slightly less than 3.5, thereby inhibiting Jahn-Teller to reduce distortion of spinel structure damage. A modified method is comprised of some transition metal ions, such as Co, Cr, Ni, Fe and Ti plasma to replace part of the Mn material.pearl jewelry
This paper adopts the traditional solid phase synthesis of spinel LiMnO standard, and electrochemical methods ( constant current charge and discharge, coulomb titration, cyclic voltammetry, AC impedance method ) and XRD, X, SEM were studied, the thermodynamic properties of charge discharge performance and cycle performance and its mechanism.

Preparation with different valence states of several cations ( Ni, Cr, V, Mo ) modified four yuan of spinel LiMMnO intercalation compounds as cathode material of lithium secondary battery two, the Li / LiMMnO cell was investigated by electrochemical and X ray diffraction study. In this paper the research work, not through low temperature sol-gel method was successfully prepared a new 3V spinel material CR modified LiO-yMnO ( y = 4 ) cation defect spinel phase, on the structure and electrochemical properties of made preliminary research. Keywords: lithium manganese spinel, cathode materials, lithium ion battery,down changes
doping, transition metal ions.

Positive spinel cheap, non-toxic, and has large electrochemical capacity, was found to be expensive to replace, toxic LiCoO_2 lithium ion battery anode materials is one of the best candidate. The capacity of the LiMn_2O_4 attenuation problem is to restrict its commercial bottleneck. Ion doping can effectively improve the electrochemical performance of LiMn_2O_4. This article reviews the domestic and foreign lithium ion battery anode material LiMn_2O_4 based on the literature review, with Li_2CO_3 and EMD as main raw materials by solid-phase reaction to prepare the Mg / F doped lithium manganese spinel oxide, and its application in power polymer lithium ion battery ( PLIB ), combined with XRD, SEM and electrochemical performance test means, on the structure, electrochemical properties and the relationship between the two.

Study found that, 750 deg.c 20h prepared with uniform cubic structure and grain size phase error accumulation and is conducive to the conductive agent of acetylene black in the active material particles bridging the microstructure characteristics of spinel lithium manganese oxide. The electrochemical testing results show, Mg doped LiMn_2O_4 spinel has good cycle performance.golden south sea pearls The 0.5C charge-discharge magnification, _ ( LiMn 1.92 ) Mg ( 0.08) O_4 first discharge capacity is about 90mAh / g ( vs.Lj ), a LiMn_2O_4 102mAh / g low, but the cycling performance significantly improved: after 300 cycles, no discernible decay capacity.

Spinel theory (wB%) : MgO 28.2, Al2O3 71.8. Isomorphism is very common. Mg2, Zn2, Mn2 by Fe2 isomorphic substitution, Mg-Fe, Mg-Zn can be formed between complete isomorphous series, the end member minerals are respectively called magnesia spinel MgAl2O4, iron, zinc spinel spinel FeAl2O4 ZnAl2O4. Al3, Cr3, Fe3, V3 often substitute; Al-Cr was a complete isomorphous series, the second end member respectively magnesium spinel MgAl2O4 and MgCr2O4 magnesium chromite.

While the Al3 is Fe3, V3 instead of more limited. Mn class matter like instead of up to 1%; substitution of Ti 0.5%. Magnetite and iron titanium spar is a continuous solid solution, due to 2Fe3 = Ti4 Fe2 instead of formation.