Affiliation:
1. Key Laboratory of Colloid and Interface Chemistry Ministry of Education School of Chemistry and Chemical Engineering Shandong University Jinan 250100 P. R. China
2. Electron Microscopy Centre Shandong University Jinan 250100 P. R. China
3. School of Nano Technology and Nano Bionics University of Science and Technology of China Hefei 230026 P. R. China
4. School of Physical and Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
Abstract
AbstractDual‐ion batteries, as one of the most promising alternatives to Li‐ion batteries, face severe challenges in terms of side reactions, particularly at the anode. These side reactions result in the consumption of limited cations and the deactivation of anions in graphite during cycling. To date, most reports are focused on reducing these side reactions. Here, a new way is proposed to achieve the stable cycling of dual‐ion batteries using Mg as an example. Mg can be oxidized to Mg2+ during the discharge process, thereby replenishing the cation loss due to the side reactions. Meanwhile, anions are released from graphite to maintain the charge balance in the electrolyte. Another advantage is that the formation of Li3Mg7 during cycles facilitates Li plating/stripping. Therefore, Mg||Graphite exhibits a high Coulombic efficiency (≈96.5%) and a stable cycling performance (≈94.6% after 1700 cycles at 2 C) even without prelithiation, much better than Cu||Graphite and Graphite||Graphite. The mechanism also works for other active metals, such as K, Ca, and Na. The results demonstrate the promising potential of this strategy.
Funder
National Natural Science Foundation of China
Natural Science Foundation of Shandong Province
Subject
Electrochemistry,Condensed Matter Physics,Biomaterials,Electronic, Optical and Magnetic Materials