Potassium-ion batteries (PIBs) have been considered as promising candidates in the post-lithium-ion battery era. Till now, a large number of materials have been used as electrode materials for PIBs, among which vanadium oxides exhibit great potentiality. Vanadium oxides can provide multiple electron transfers during electrochemical reactions because vanadium possesses a variety of oxidation states. Meanwhile, their relatively low cost and superior material, structural, and physicochemical properties endow them with strong competitiveness. Although some inspiring research results have been achieved, many issues and challenges remain to be further addressed. Herein, we systematically summarize the research progress of vanadium oxides for PIBs. Then, feasible improvement strategies for the material properties and electrochemical performance are introduced. Finally, the existing challenges and perspectives are discussed with a view to promoting the development of vanadium oxides and accelerating their practical applications.

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Under the influence of marine conditions on nuclear powered ships, the liquid storage in the Pressurizer shake violently, which affects the normal operation of the Pressurizer and even causes safety accidents. Therefore, it is extremely urgent to design an anti-wave device for the Pressurizer. This paper studies a Pressurizer model with a ring-shaped plate. Using numerical simulation software, the VOF method is used to couple the k-ε model to simulate the liquid level fluctuation of the two Pressurizers with and without anti-wave device under different external excitation cycles. The phenomenon of internal liquid level fluctuation during movement was analyzed, and the pressure transient change characteristics of the pressure monitoring points arranged on the pressurizer were analyzed, so as to compare the different axial sections and the overall water level shaking amplitude. By comparing the simulation results, it is found that when the external excitation period is T = 2∼2.5s, the ring-shaped plate studied in this study can suppress the shaking of the liquid storage in the Pressurizer significantly.

The pressurizer of floating reactor moves dramatically with the of ocean waves, and liquid in pressurizer will slosh when subjected to additional inertial force. To study the hydro characteristics of the liquid in pressurizer, this paper analyzed the flow field and pressure variation of pressurizer under typical moving conditions. Combined with the influence factors of typical motion on the transient pressure variation characteristics at monitoring position under different working conditions, optimize the differential pressure measuring method of liquid level through numerical simulation, result in reduce the liquid level measuring deviation. Traditional numerical approach of liquid sloshing is improved based on the modified motion equation and coordinate transformation matrix approach. Combined with the moving grid and modified algorithm. Through comparison. The results show that the liquid level measuring deviation of heave motion with vertical additional acceleration and the pressure variation of rolling motion is mainly caused by the spatial position variation of the model and the liquid free surface. The mechanism of coupling of heave motion and rolling motion can be comprehensively considered in combination with the influences of every individual motion. In addition, through verification, the liquid level measuring can be corrected according to the attitude data and geometric information of pressurizer.