用包裹沉淀法合成了具有尖晶石结构的可用作锂离子二次电池正极材料的锂锰氧（LiMn2O4）化合物。对材 料进行了X射线衍射、循环伏安、充放电等测试，实验结果表明，所合成的材料具有标准尖晶石结构和较好的电化 学可逆性能，该材料在EC2DMC（1∶1，体积比）+1mol/L LiPF6电解液中表现出较优良的充放电性能，其放电容量达120mAh/g。

LiFePO4/C composite was synthesized by high temperature solid2state reaction using iron (Ⅱ) oxalate, ammonium di2hydrogen phosphate and lithium carbonate with a kind of carbohydrate dissolved in the dispersant (eth-anol) as carbon sources added to the synthetic precursor. The samples were characterized by X2ray diff raction (XRD), scanning elect ron microscopy observations (SEM), charge/ discharge test, cyclic voltammet ry(CV) and carbon analysis. The result s show that the synthesis of LiFePO4/C has ordered olivine st ructure. The carbon has two advantages: optimizing particle size of LiFePO4 and increasing the elect ronic conductivity and high Li+diffusivity. The cathode material can demonst rate a charge/discharge flat voltage of 3.4V (vs Li+/Li). Especially the active material with 15% and 20% carbohydrate added according to the final product of lithium iron phosphate shows very good elect rochemical performance delivering about initial 150.2 mA·h·g-1 and 162.0 mA·h·g-1 specific capacity respectively at 0.1 C rate and the carbon contents in the final production are only 5.17% and 5.29%, respectively.

Layered LiNi1/3Co1/3Mn1/3O2 materials were synthesized using a nickel2cobalt2manganese carbonate pre2 cursor obtained by chemical co2precipitation. The [Ni1/3 Co1/3 Mn1/3] CO3 precursor and the LiNi1/3 Co1/3 Mn1/3 O2 powders were characterized by X2ray diff raction (XRD) and scanning elect ron micrograph (SEM). The SEM analysis shows that these particles possess uniform and spherical morphology. The elect rochemical properties of the LiNi1/3 2 Co1/3Mn1/3O2 cathode material for rechargeable lithium2ion bat teries such as the galvanostatic charge2discharge per formance and cyclic voltammet ry(CV) were measured. The result s show that an initial discharge capacity of 190. 29 mA·h·g-1 is obtained in the voltage range of 2.5 4.6 V and at a current rate of 0.1 C at 25 ℃. The discharge capacity increases linearly with the increase of the upper cut2off voltage limit.

LiFePO4/C composites with good rate capability and high energy density were prepared by adding sugar to the synthetic precursor. A significant improvement in electrode performance was achieved. The resulting carbon contents in the sample 1 and sample 2 are 3.06% and 4.95%(mass fraction), respectively. It is believed that the synthesis of LiFe2PO4 with sugar added before heating is a good method because the synthesized particles having uniform small size are covered by carbon. The performance of the cathodes was evaluated using coin cells. The samples were characterized by X2ray diffraction and scanning electron microscope observation. The addition of carbon limits the particles size growth and enables high electron conductivity. The LiFePO4/C composites show very good electrochemical performance delivering about 142 mAh/g specific capacity when being cycled at the C/ 10 rate. The capacity fade upon cycling is very small.

On the basis of serial laboratory research and industrial test, the mechanism of saving energy and reducing carbon consumption of property2modified prebaked anode in aluminum electrolysis was discussed. It is considered that the anodic over voltage is affected by the concentration of carbon monoxide surrounding anode. The property2modified prebaked anode can restrain the production of carbon monoxide. The reason of reducing carbon consumption was also ana lyzed, the result shows that besides physical action, chemical action also exists in the process where additives change the reaction rate of anodes.