Lithium-CO2 batteries are attractive energy-storage systems for fulfilling the demand of future large-scale applications such as electric vehicles due to their high specific energy density. However, a major challenge with Li-CO2 batteries is to attain reversible formation and decomposition of the Li2 CO3 and carbon discharge products. A fully reversible Li-CO2 battery is developed with overall carbon neutrality using MoS2 nanoflakes as a cathode catalyst combined with an ionic liquid/dimethyl sulfoxide electrolyte. This combination of materials produces a multicomponent composite (Li2 CO3 /C) product. The battery shows a superior long cycle life of 500 for a fixed 500 mAh g-1 capacity per cycle, far exceeding the best cycling stability reported in Li-CO2 batteries. The long cycle life demonstrates that chemical transformations, making and breaking covalent CO bonds can be used in energy-storage systems. Theoretical calculations are used to deduce a mechanism for the reversible discharge/charge processes and explain how the carbon interface with Li2 CO3 provides the electronic conduction needed for the oxidation of Li2 CO3 and carbon to generate the CO2 on charge. This achievement paves the way for the use of CO2 in advanced energy-storage systems.

中文翻译：

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具有碳中性的长寿命锂-二氧化碳电池。

锂-二氧化碳电池因其高的比能量密度而成为满足未来大规模应用（如电动汽车）需求的有吸引力的储能系统。但是，Li-CO2电池的主要挑战是实现Li2 CO3和碳放电产物的可逆形成和分解。使用MoS2纳米薄片作为阴极催化剂，结合离子液体/二甲基亚砜电解质，开发出一种具有完全碳中性的完全可逆的Li-CO2电池。这种材料组合产生了多组分复合材料（Li2 CO3 / C）。对于每个循环固定的500 mAh g-1容量，该电池显示出500的超长循环寿命，远远超过了Li-CO2电池中报告的最佳循环稳定性。较长的循环寿命表明化学转化，形成和打破共价键的C canO键可用于储能系统。理论计算用于推论可逆放电/充电过程的机理，并解释与Li2 CO3的碳界面如何提供Li2 CO3和碳的氧化以在充电时生成CO2所需的电子传导。这一成就为在高级储能系统中使用二氧化碳铺平了道路。