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A Cu2ZnSn(S,Se)4 (CZTSSe) absorber for thin film solar cells was fabricated by nonaqueous thiourea–metal–oxygen sol–gel processing followed by post-selenization. The effects of selenization temperature, selenization time and metal composition on the film microstructure and phase were investigated. Under optimized process parameters, the complete CZTSSe solar cell devices produced efficiency values as high as 8.08% with a short-circuit current density of 32.78 mA cm−2, an open-circuit voltage of 487 mV, and a fill factor of 51%. The factors that limit the device performance were discussed. The nonuniform film thickness and nonhomogeneous chalcogen components should be responsible for the low shunt resistance and thereby low open-circuit voltage; and the presence of a large number of voids and thick Mo(S,Se)2 interface layer may be the main reasons for high series resistance, detrimental to short-circuit current density and fill factor.

A detailed investigation of the effects of Nd on the microstructure, mechanical properties and electrochemical properties of lead anode in 160g.L-1 at 35°C was carried out. Galvanostatic polarization and Chronopotentiometry (CP) were used to study the electrochemical behavior ( such as anodic potential, corrosion rate and the composition of passive film) of the Pb and Pb-Nd anodes. The metallographic structure and passive film morphology of Pb and Pb-Nd anodes were observed and analyzed using polarizing microscope and scanning electronic microscopy (SEM), respectively. The experimental results show the grains become smaller and aggregation of PbxNdy become severe as the content of Nd increases. The addition of Nd enhances the formation of PbO2, inhibits the formation of PbSO4 and PbO and reduces the anodic potential. However, Holes presenting on rough passive film of high Nd content Pb-Nd anodes accelerate the corrosion.

Low-temperature performance of LiBF4 and LiPF6-based electrolytes in LiFePO4/Li and graphite/Li half cells was investigated. In the temperature range from 0 °C to −40 °C, electrochemical impedance spectroscopy (EIS) results show that the charge-transfer resistance (Rct) of graphite/Li cell decreases, the Rct of LiFePO4/Li cell increases, and sum resistance of LiFePO4/Li and graphite/Li cell decreases when replacing LiPF6 with LiBF4. In the temperature range from 25 °C to −40 °C, energy barrier (W) for Li-ion jump at the solid electrolyte interface (SEI) alters slightly from 16.04 kJ/mol to 13.60 kJ/mol in LiFePO4/Li cells, but declines greatly from 46.47 kJ/mol to 19.81 kJ/mol in graphite/Li cells when using LiBF4 instead of LiPF6, meanwhile, activation energy (ΔG) of electrode reaction is approximately the same (∼60 kJ/mol). The above results indicate that the ionic conductivity is the main limiting factor for low-temperature performance of electrolytes in LiFePO4/Li cell, while factors related with electrolyte-interface are more crucial in graphite/Li cell than in LiFePO4/Li cell.

采用直流反应磁控溅射技术在玻璃基底上制备了太阳电池用CuInS 2 薄膜. 以X射线能量色散谱仪、扫描电镜、X射线衍射仪、冷热探针和霍尔效应测试系统对薄膜进行了表征. 结果表明, 薄膜成分可通过调整Cu靶和In靶的功率比PCu/PIn来进行调控; 而薄膜形貌则取决于靶功率比和薄膜的成分. 随着PCu/PIn的增大, 薄膜物相由富铟相向CuInS 2 转变. 对于CuInS 2 薄膜, 提高铜铟原子比[Cu]/[In]可改善薄膜的结晶质量. 但当薄膜富铜时, 过高的[Cu]/[In]又会导致薄膜结晶质量的下降. 当CuInS 2 薄膜为富铜与略微贫铜时, 其导电类型为P型; 且载流子浓度随[Cu]/[In]增加而增大, 并远高于其它贫铜薄膜. CuInS 2 薄膜的载流子迁移率明显高于富铟相薄膜; 且随着[Cu]/[In]的提高, CuInS 2 薄膜的载流子迁移率呈上升趋势, 而电阻率则迅速下降.

According to the poor performance about conductivity and cycle properties of conductive polyaniline (PANI) electrode material. The structure control techniques were used and the C/PANI compound electrod materials and fibrous PANI electrod materials were prepared.The electrochemical performance of PANI with different structure was examined .The examination results indicated: The structure control methods have obvious influnce on the electrochemical performance of PANI. The improvement of PANI structure may enhance the penetration of electrolyte and the intercalation of electrolyte ion. At the 2mA discharge current , the max capacitance of PANI-C and PANC-S is 435F/g and 387F/g, respectively .The capacitance retention rate of PANI-C and PANC-S after 500th cycle is 77% and 96%. The ion diffusion impedance of PANI-S material was lowest and show best capacitance and cycle performance.

Mn/Pb composite oxides were prepared by solid-state reaction by KMnO4 with manganese acetate and lead acetate at low temperature. The products were characterized by XRD and TEM. The results show that the composite oxides are nano-size and amorphous structure. Electrochemical characterizations were performed by cyclic voltammetry (CV) and constant current charge-discharge in a three-electrode system. The potential windows of Mn/Pb composite oxides electrode are increased. With increasing the ratio of Pb, the specific capacitance goes through a maximum at 20% mol Pb. The specific capacitance of pure MnO2 is 158 F/g and is improved to 180 F/g for the Mn0.8Pb0.2Ox composite oxide by constant current discharge.

Inert anode has been a hot issue in the aluminum industry for many decades. With the help of FEA (finite element analysis) software ANSYS, a model was developed to simulate the thermal stress distribution working condition of an inert anode. To reduce its thermal stress, the effect of some parameters on the thermal stress distribution was investigated, including the anode height, the anode radius, the hole depth, the hole radius, and the radius of inner chamfer and outer chamfer. The results showed that in the actual working condition of an inert anode, there existed a large axial tensile stress near the tangent interface between the anode and bath, which was the major cause of anode breaking. Increasing the anode height and reducing the hole depth properly seemed to be beneficial for the stress distribution. With the increase of anode radius, the stress distribution became better first and then deteriorated, the reasonable value was between 0.045 to 0.06m. The hole radius had a significant effect on the stress and a smaller radius would reduce the thermal stress. The effect of the radius of the inner chamfer and the outer chamfer was less than other parameters.

Two full 3D steady mathematical models are developed by finite element method (FEM) to calculate coupled physics fields: the electro-magnetic model is built and solved first and so is the fluid motion model with the acquired electromagnetic force as source body forces in Navier-Stokes equations. Effects caused by the ferromagnetic shell, busbar system around, and open boundary problem as well as inside induced current were considered in terms of the magnetic field. Furthermore, a new modeling method is found to set up solid models and then mesh them entirely with so-called structuralized grids, namely hex-mesh. Examples of 75kA prebaked cell with two kinds of busbar arrangements are presented. Results agree with those disclosed in the literature and confirm that the coupled simulation is valid. It is also concluded that the usage of these models facilitates the consistent analysis of the electric field to magnetic field and then flow motion to the greater extent, local distributions of current density and magnetic flux density are very much dependent on the cell structure, the steel shell is a shield to reduce the magnetic field and flow pattern is two dimensional in the main body of the metal pad.