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The α-Ni(OH)2 coated with manganese (Mn) materials was synthesized by the chemical precipitation method, and the electrochemical properties were investigated. The results showed that the ingredient of the coating is a mixture of MnO2 and Mn2O3, and the coating can inhibit the intercalated anions escape and stabilize the α-Ni(OH)2 phase structure in KOH alkaline solution. The coated electrodes have higher discharge capacities and higher capacity retention rates than the uncoated α-Ni(OH)2 electrode, the discharge capacity of Mn-coated electrodes is over 350 mAh g−1, and the capacity retention rate exceeds 92%, separately. The reason may be that the Mn coatings can block or decelerate water molecule and the anion to escape from the interlayers, therefore prevent α phase structural collapse and maintain high discharge capacity during a long lifespan cycle. Therefore, the Mn coating α-Ni(OH)2 is a promising candidate for high-power Ni-MH batteries.

Reducing cobalt dependency has attracted great interest for lithium batteries manufacturing due to limited cobalt resources and high prices. A highly promising LiNi0.6Co0.05Mn0.35O2 (NCM60535) high-nickel low cobalt lithium layered oxide cathode material is successfully prepared by systematically examining the two key synthesis conditions of pH and annealing temperature. The obtained materials exhibit a uniform size distribution, good spherical morphology, clear structure, and homogeneous element distribution. NCM60535 shows competitive electrochemical properties: when compared with the LiNi1/3Co1/3Mn1/3O2, with a higher output specific capacity and cycling stability at 4.3 V low voltage; when compared with the LiNi0.8Co0.1Mn0.1O2, with a comparable discharge capacity but relatively poor cycling stability at 4.5 V high voltage. A new type of electrolyte that combines high lithium salt concentration, EC-free solvent system, and VC and LiPO2F2 functional additives is designed and greatly improves the electrochemical properties of the material under high voltage. Moreover, it also delivers superior electrochemical properties in high voltage lithium full battery (270 Wh Kg−1). And we suggest that NCM60535 is expected to become a substitute for the currently widely commercialized LiNi1/3Co1/3Mn1/3O2 (NCM333), LiNi0.5Co0.2Mn0.3O2 (NCM523), LiNi0.6Co0.2Mn0.2O2 (NCM622), and LiNi0.8Co0.1Mn0.1O2 (NCM811) due to its relatively low production cost and competitive electrochemical properties.

The ammonia-low hydroxide coprecipitation process has successfully synthesized Ni0.6Co0.2Mn0.2(OH)2 precursor by replacing ammonia with NH4+ and lowering the pH of the salt solution with acid. NH4+ and H+ increase the diffusion range of the salt solution and both react with OH−, which would reduce the nucleation rate and increase the complexation under low ammonia concentration conditions. The optimal pH of coprecipitation is determined from the theoretical calculation on the competitive relationship between complexation (Me(NH3)n2+) and precipitation (OH−) using chemical equilibrium and solubility product constant. And compared with other different complexing agents (e.g., NH4+, H+, and NH3), the material obtained with both NH4+ and H+ has the optimized particle morphology, size, composition, and element distribution. The resulting LiNi0.6Co0.2Mn0.2O2 cathode material exhibits superior electrochemical properties, when compared to a commercial sample, with a high initial discharge capacity (176.6 mAh g−1), cycling stability (91.9% retention for 100 cycles), and rate capability (115.7 mAh g−1 at 3C). Moreover, it also demonstrates excellent electrochemical performance in lithium-ion full batteries matched with commercial graphite or Si/C anodes. Ammonia-low coprecipitation synthesis would greatly reduce the treatment cost of production wastewater, improve the working environment of operators, and protect the natural ecological environment of the earth.

To analyze the influence of different soil properties on pile foundation load-bearing characteris- tics, taking a section of railway in Xi'an and a bridge of Xi'an as test area, and by field static load test to study load transfer characteristics after the test piles under axial pressure, including the distribution of axial force, pile lateral friction, tip resistance traits, ultimate bearing capacity determine, and compare with the theory bearing capacity. Experimental results show that, adjacent soil properties change large, axial force and lateral friction mutation at the junction of corresponding soil layer. Silty clay in different parts is below ground, and its lateral friction plays much difference. Pile lateral friction plays an important role in bearing capacity, but the role of round gravel soil end bearing capacity to pile bearing capacity can't be ignored. Tests calculate pile bearing ca- pacity significantly larger than standardized formula calculation bearing capacity, which are respectively 55.35% and 119.1%. And give the similar project condition the suggested values of pile bearing capacity and soil friction, to provide reference for similar pile foundation design.