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With the development of social industrialization, energy issues have become a hot topic at present. Traditional lithium-ion batteries, due to their poor safety and high cost, cannot meet the current application needs in the energy storage field in the long term. Therefore, the development of suitable new energy has aroused people's deep thinking. Aqueous zinc-ion batteries (AZIBs) have attracted attention from the scientific research community in recent years due to their high safety, cleanliness, and other advantages. However, dendrites are easily grown on the zinc anode, and free water molecules can also corrode the zinc anode, causing side reactions such as hydrogen evolution and passivation, seriously affecting the long-term cycling performance and stability of the battery. This work introduces a new type of ionic liquid additive 1-cyanobutyl-3-methylimidazole chloride (MCBI) to optimize aqueous electrolytes. Before the deposition of zinc ions on the anode surface, MCBI cations will preferentially land on the anode. Due to their special structures of Electron-withdrawing group and nitrogen heterocycles, they will tightly adsorb on the zinc surface in a unique shape of the “Check mark” posture. This provides abundant sites for the deposition of zinc ions, allowing zinc atoms to arrange regularly between MCBI ions, thereby reducing the generation of dendrites. Due to the steric hindrance effect, by-products (Zinc hydroxide sulfate) will also accumulate in an orderly manner around additive ions, forming channels for uniform deposition of zinc ions; The hydrophobic alkyl groups of MCBI cations will repel most of the free water molecules outside the anode, thereby reducing hydrogen evolution reaction (HER). In this work, under the optimal concentration conditions, the Coulomb efficiency of Zn//Cu asymmetric cell with MCBI additive can reach 99. 37% after 200 cycles; Zn//Zn symmetric batteries can stably cycle for more than 1600 h at low current density (0. 5 mA/cm2), and can cycle for more than 1000 h at 10 mA/cm², 5 mA·h/cm². Finally, VO2 as the cathode maintains a high-capacity retention rate of 88. 5% after 500 cycles in the full battery. This work provides new ideas for the anode modification strategy of aqueous zinc ion batteries. [ABSTRACT FROM AUTHOR]

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In order to consider the effect of cooling conditions on microstructure formation during casting of Cu-Ni-Si alloy (Corson alloy), the microstructures of unidirectional solidification of the alloy were evaluated. Ingots of Corson alloy with several cooling conditions were prepared by Mizuta method, and microstructural observations and analysis of the distribution of added elements were performed. The primary and secondary dendrite arm spacings (P-DAS and S-DAS) became smaller with increasing cooling rate, and it was found that P-DAS and S-DAS can be accurately approximated by multiplier of cooling rate times temperature gradient, and by that of cooling rate, respectively. Between secondary dendrites, Si was enriched from the initial solidification zone to the final solidification zone, and Ni was almost constant around the initial solidification zone and enriched slightly around the final solidification zone. The Si enrichment was larger under the condition of lower cooling rate, which is expected to be closer to the equilibrium state. In this study, it was found for Corson alloy that DAS became bigger and Si enrichment between secondary dendrites was larger under the condition of lower cooling rate, and Ni enrichment was not affected by cooling rate. [ABSTRACT FROM AUTHOR]

Dendrites are formed on the interface because its stability is destroyed in the charging process for metal-air battery, which leads to the safety and short life of the metal-air battery. Focused on the problems, the researchers Investigated the dendrites growth though theory, experiment and simulation to suppress it. In this paper, the mechanism of dendrites growth in the electrodeposition for metal-air batteries was firstly addressed and analyzed. Then, the resent researches about the dendrite suppression methods in the charging process for metal-air batteries were overviewed. The results show that the modification and structural design of the metal negative electrode and the improved electrolyte can effectively inhibit the dendrites growth. Adjusting the temperature nearby the anode interface to regulate the uniform deposition can inhibit the growth of dendrites. From the present investigation and results, the following research method should combine the experiment and simulation and focus on the synergistic effect of current characteristics, electrolyte properties an dcatalyst catalytic performance on dendrite suppression. The theory of dendrites suppression can be revealed and the effective method of dendrites suppression of metal anode for metal-air battery can be obtained. [ABSTRACT FROM AUTHOR]

Dendrite morphology is drastically changed due to the liquid flow, such as iorced and natural convections, during the solidification of metallic alloys. W e have developed a phase-field lattice Boltzmann method to simulate the dendrite growth during the alloy solidification in the presence of the liquid flow. Here, we have employed the phase-field and lattice Boltzmann methods to express the dendrite growth and liquid flow, respectively. In addition, a parallel computation using multiple graphical processing units in a supercomputer has been enabled to accelerate the phase-field lattice Boltzmann simulation. In this report, the phase-field lattice Boltzmann model is briefly explained, and some dendrite growth simulations using the model are introduced. [ABSTRACT FROM AUTHOR]

In order to research the Zn-polyaniline secondary battery life cycle impact factors, the five factors of influence on the cyclic life for Zn-PANi secondary batteries have been investigated electrochemically, which include materials degradation of the positive electrode due to overcharge, passivation of the negative electrode, dendrite formation, corrosion of the current collector and drying up of the electrolyte. The test results indicate that the main influence factor is the short-circuit aroused by the dendrite formation on the negative electrode, which enable the battery to have the life of only 70 cycles. Secondly, the degradation of positive electrode by over charge causes the self-discharge of battery, which reduces the battery cycle life significantly. In addition, the drying up of electrolyte, the passivation of the negative electrode and the choice of the current collector, all these bring about influences to the cycle life of battery to a certain extent. [ABSTRACT FROM AUTHOR]