Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, P R China.
Sci Rep. 2013;3:1946. doi: 10.1038/srep01946.
Rechargeable batteries made from low-cost and abundant materials operating in safe aqueous electrolytes are attractive for large-scale energy storage. Sodium-ion battery is considered as a potential alternative of current lithium-ion battery. As sodium-intercalation compounds suitable for aqueous batteries are limited, we adopt a novel concept of Li(+)/Na(+) mixed-ion electrolytes to create two batteries (LiMn2O4/Na0.22MnO2 and Na0.44MnO2/TiP2O7), which relies on two electrochemical processes. One involves Li(+) insertion/extraction reaction, and the other mainly relates to Na(+) extraction/insertion reaction. Two batteries exhibit specific energy of 17 Wh kg(-1) and 25 Wh kg(-1) based on the total weight of active electrode materials, respectively. As well, aqueous LiMn2O4/Na0.22MnO2 battery is capable of separating Li(+) and Na(+) due to its specific mechanism unlike the traditional "rocking-chair" lithium-ion batteries. Hence, the Li(+)/Na(+) mixed-ion batteries offer promising applications in energy storage and Li(+)/Na(+) separation.
可充电电池由低成本且丰富的材料制成，在安全的水性电解液中运行，因此具有大规模储能的吸引力。钠离子电池被认为是当前锂离子电池的一种潜在替代品。由于适合水性电池的钠离子嵌入化合物有限，我们采用了一种新的概念，即 Li(+)/Na(+)混合离子电解液，以创建两种电池（LiMn2O4/Na0.22MnO2 和 Na0.44MnO2/TiP2O7），它们依赖于两个电化学过程。一个涉及 Li(+)的插入/提取反应，另一个主要涉及 Na(+)的提取/插入反应。两种电池的比能量分别为 17 Wh kg(-1)和 25 Wh kg(-1)，基于活性电极材料的总重量。此外，由于其特殊的机制，不同于传统的“摇椅”锂离子电池，水性 LiMn2O4/Na0.22MnO2 电池能够分离 Li(+)和 Na(+)。因此，Li(+)/Na(+)混合离子电池在储能和 Li(+)/Na(+)分离方面具有广阔的应用前景。
