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Battery fault diagnosis is a key problem to ensure the safe operation of electric vehicles. In order to achieve accurate voltage prediction during the real operation of electric vehicles, this study proposed an electric vehicle real voltage prediction algorithm based on PCC-CNN-LSTM. First, the input and output characteristics were determined by Pearson correlation coefficient method. Considering the sampling time of individual cells in different battery packs, the number of cells and the working range of voltage, the parameters of the algorithm model were determined. Then, the sequential features in the voltage data were mined by CNN for feature extraction and input into LSTM for model training, which effectively solves the problem that the LSTM input feature dimension is too large to grasp the effective information, which makes the prediction accuracy decrease. Through the real vehicle test, for different types of battery packs, the evaluation indexes of the CNN-LSTM-based model are superior to those of other algorithm models (CNN, LSTM, GRU, and CNN-GRU). Finally, the superiority, reliability, and robustness of the proposed algorithm are verified by comparing with other algorithm models. [ABSTRACT FROM AUTHOR]

Highlights: The unique layered structure and excellent photoelectric properties of MoS2 facilitate the abundant generation and rapid transfer of photo-excited carriers, which accelerate the CO2 reduction and Li2CO3 decomposition upon illumination. MoS2-based photo-energized Li–CO2 battery displays ultra-low charge voltage of 3.27 V, high energy efficiency of 90.2%, superior cycling stability after 120 cycles and high rate capability. The low-temperature Li–CO2 battery achieves an ultra-low charge voltage of 3.4 V at –30 °C with a round-trip efficiency of 86.6%. Li–CO2 batteries are considered promising energy storage systems in extreme environments such as Mars; however, severe performance degradation will occur at a subzero temperature owning to the sluggish reaction kinetics. Herein, a photo-energized strategy adopting sustainable solar energy in wide working temperature range Li–CO2 battery was achieved with a binder-free MoS2/carbon nanotube (CNT) photo-electrode as cathode. The unique layered structure and excellent photoelectric properties of MoS2 facilitate the abundant generation and rapid transfer of photo-excited carriers, which accelerate the CO2 reduction and Li2CO3 decomposition upon illumination. The illuminated battery at room temperature exhibited high discharge voltage of 2.95 V and mitigated charge voltage of 3.27 V, attaining superior energy efficiency of 90.2% and excellent cycling stability of over 120 cycles. Even at an extremely low temperature of − 30 °C, the battery with same electrolyte can still deliver a small polarization of 0.45 V by the photoelectric and photothermal synergistic mechanism of MoS2/CNT cathode. This work demonstrates the promising potential of the photo-energized wide working temperature range Li–CO2 battery in addressing the obstacle of charge overpotential and energy efficiency. [ABSTRACT FROM AUTHOR]

This study compared the biomechanical characteristics of different treatment strategies based on finite element analysis. Posterior tilt and valgus angle were measured on X-ray from ten valgus-impacted femoral neck fractures, and 7 finite element models that were generated to compare the stress and displacement. The results showed that in the intact femur, von Mises stress was concentrated at the medial and inferior sides of the femoral neck. In valgus-impacted femoral neck fractures, von Mises stress was at the same locations but was 5.66 times higher than that in the intact femur. When 3 cannulated screws were used for internal fixation, anatomic reduction diminished the stress at the fracture end from 140.6 to 59.14 MPa, although displacement increased from 0.228 to 0.450 mm. When the fracture was fixed with a sliding hip screw (SHS) + cannulated screw, there was less stress at the fracture end and greater displacement with anatomic reduction than that without reduction (stress: 15.9 vs 37.9 MPa; displacement: 0.329 vs 0.168 mm). Therefore, the SHS + cannulated screw has superior biomechanical stability than 3 cannulated screws, and is recommended following anatomic reduction to treat valgus-compacted femoral neck fractures. [ABSTRACT FROM AUTHOR]

An amorphous hydrated vanadium oxide induced by Zn2+ intercalation in Mg-ion inserted V2O5·nH2O (MgVOH) is developed as a high-performance cathode for ZIBs. In particular, zinc pyrovanadate as the product of the second phase transition is found to suppress the dissolution issue of the vanadium species for the cathode to facilitate long lifespan. [ABSTRACT FROM AUTHOR]