Photovoltaic cells (PVs) are able to convert solar energy to electric energy, while energy storage devices are required to be equipped due to the fluctuations of sunlight. However, the electrical connection of PVs and energy storage devices leads to increased energy consumption, and thus energy storage ability and utilization efficiency are decreased. One of the solutions is to explore an integrated photoelectrochemical energy conversion-storage device. Up to date, the integrated photo-rechargeable Li-ion batteries often suffer from unstable photo-active materials and flammable electrolytes under illumination, with concerns in safety risks and limited lifetime. To address the critical issues, here a novel photo-rechargeable aluminum battery (PRAB) is designed with safe ionic liquid electrolytes and stable polyaniline photo-electrodes. The integrated PRAB presents stable operation with an enhanced reversible specific capacity ≈191% under illumination. Meanwhile, a simplified continuum model is established to provide rational guidance for designing electrode structures along with a charging/discharging strategy to meet the practical operation conditions. The as-designed PRAB presents an energy-saving efficiency ≈61.92% upon charging and an energy output increment ≈31.25% during discharging under illumination. The strategy of designing and fabricating stable and safe photo-rechargeable non-aqueous Al batteries highlights the pathway for substantially promoting the utilization efficiency of solar energy.

中文翻译：

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稳定的光充电铝电池可提高能源利用率


光伏电池（PV）能够将太阳能转化为电能，但由于太阳光的波动，需要配备储能装置。然而，光伏发电与储能装置的电连接导致能源消耗增加，从而导致储能能力和利用效率下降。解决方案之一是探索集成光电化学能量转换存储装置。迄今为止，集成光充电锂离子电池经常面临光照下不稳定的光活性材料和易燃电解质的问题，存在安全风险和有限的使用寿命。为了解决这个关键问题，本文设计了一种新型光充电铝电池（PRAB），采用安全的离子液体电解质和稳定的聚苯胺光电极。集成的 PRAB 在光照下表现出稳定的运行，增强的可逆比容量约 191%。同时，建立了简化的连续体模型，为设计电极结构以及满足实际操作条件的充放电策略提供合理指导。设计的PRAB在充电时的节能效率约为61.92%，在光照下放电时的能量输出增量约为31.25%。设计和制造稳定、安全的光可充电非水铝电池的策略突出了大幅提高太阳能利用效率的途径。