SiO x -based anode materials are considered to be promising and have been gradually commercialized due to their high specific capacity as well as the acceptable volume change during lithiation/delithiation and preferable cycling stability compared to that of Si. Nevertheless, their inherently low Coulombic efficiency hinders the large-scale application. Up to now, researchers have paid much attention to the initial Coulombic efficiency and developed a series of effective prelithiation strategies. However, the subsequent cycles (focusing on the 2nd to 10th), during which the SiO x anode suffers great lithium consumption as well, have received scarcely any concerns. In this work, a strategy of high-temperature (50 °C) initial charge after an overcapacity prelithiation for a SiO x -based full-cell battery is proposed. As high temperature can promote the reaction between lithium and the SiO 2 matrix of SiO x , SiO 2 will experience a one-step thorough reduction rather than gradual conversion in subsequent cycles, improving the subsequent Coulombic efficiencies (SCEs) accordingly. Overcapacity prelithiation can be achieved safely at 50 °C without Li metal depositon, just enough to meet the more initial lithium demand of anode at 50 °C. Furthermore, the initial deeper reduction of SiO 2 will release extra Si, improving the reversible capacity consequently. With the 50 °C initial charge after an overcapacity prelithiation, the full-cell battery exhibits considerable capacity retention as expected. This work raises concerns on SCEs of SiO x -based anode innovatively, providing a feasible avenue for improving the capacity retention of a SiO x -based full-cell battery.

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For the applications of aqueous Li-ion hybrid capacitors and Na-ion hybrid capacitors, potassium ions are pre-inserted into MnO₂ tunnel structure, the as-prepared K_1.04Mn₈O₁₆ materials consist of <a>nanoparticles</a> and nanorods were prepared by facile high-temperature solid-state reaction. <a></a>The as-prepared materials were well studied andthey show outstanding electrochemical behavior. We assembled hybrid supercapacitors with commercial activated carbon (YEC-8A) as anode and K_1.04Mn₈O₁₆as cathode. It has high energy densities and power densities. Li-ion capacitors reach a high energy density of 127.61 Wh kg^-1at the power density of 99.86 W kg^-1 and Na-ion capacitor obtains 170.96 Wh kg^-1at 133.79 W kg^-1. In addition, the <a>hybrid supercapacitor</a>s demonstrate excellent cycling performance which maintain 97 % capacitance retention for Li-ion capacitor and 85 % for Na-ion capacitor after 10,000 cycles.

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