Abstract With the increasing global demand for lithium, lithium extraction from seawater/brine attracted extensive attentions. Selective lithiation desalination battery is a novel and promising model for this process since its good performances on selectivity, extraction capacity and energy consumption. However, multi-metal composition and possible corrosiveness of seawater/brine requires high capacity electrode with high selectivity and cycle stability. To address this issue, this work proposed a less layer graphene gauze modified Ni-rich cathode material LiNi0.6Co0.2Mn0.2O2 core-shell structure microsphere (rGO/NCM) with shell thickness of 3 nm. The graphene gauze offers high electron transfer pathways instead of ion transfer between lattices, which reduced the NCM lattice collapse probability effectively. This was verified by ex-situ XRD and electrochemical results of high capacity, good cycle stability and rate performance in both organic and aqueous systems. In the desalination battery composed of rGO/NCM as positive and activated carbon (AC) as negative, rGO/NCM//AC delivered high Li+ extraction efficiencies reaching 13.84 mg/g per 1 cycle in simulated brine by consuming only 1.4 Wh/mol Li+. The overall process produced 93% Li+ in simulated brine at optimized operating conditions. The results indicated that rGO/NCM//AC desalination battery is a promising electrochemical lithium extraction approach.

中文翻译：

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离子选择性脱盐电池从盐水中提取锂

摘要 随着全球对锂的需求不断增加，从海水/盐水中提取锂引起了广泛关注。选择性锂化脱盐电池是该过程的一种新颖且有前景的模型，因为它在选择性、提取能力和能耗方面具有良好的性能。然而，海水/盐水的多金属成分和可能的腐蚀性需要具有高选择性和循环稳定性的高容量电极。为了解决这个问题，这项工作提出了一种少层石墨烯网改性的富镍正极材料 LiNi0.6Co0.2Mn0.2O2 核壳结构微球（rGO/NCM），壳厚度为 3 nm。石墨烯网提供了高电子转移途径，而不是晶格之间的离子转移，有效降低了 NCM 晶格坍塌概率。这通过非原位 XRD 和电化学结果证实，在有机和水性体系中具有高容量、良好的循环稳定性和倍率性能。在以 rGO/NCM 为正极、活性炭 (AC) 为负极的脱盐电池中，rGO/NCM//AC 在模拟盐水中每 1 次循环仅消耗 1.4 Wh/mol Li+ 即可实现高达 13.84 mg/g 的 Li+ 提取效率. 在优化的操作条件下，整个过程在模拟盐水中产生了 93% 的 Li+。结果表明，rGO/NCM//AC 脱盐电池是一种很有前景的电化学锂提取方法。rGO/NCM//AC 在模拟盐水中通过仅消耗 1.4 Wh/mol Li+ 实现了每 1 个循环的高 Li+ 提取效率，达到 13.84 mg/g。在优化的操作条件下，整个过程在模拟盐水中产生了 93% 的 Li+。结果表明，rGO/NCM//AC 脱盐电池是一种很有前景的电化学锂提取方法。rGO/NCM//AC 在模拟盐水中通过仅消耗 1.4 Wh/mol Li+ 实现了每 1 个循环的高 Li+ 提取效率，达到 13.84 mg/g。在优化的操作条件下，整个过程在模拟盐水中产生了 93% 的 Li+。结果表明，rGO/NCM//AC 脱盐电池是一种很有前景的电化学锂提取方法。