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Abstract Dual‐ion batteries that use anions and cations as charge carriers represent a promising energy‐storage technology. However, an uncharted area is to explore transition metals as electrodes to host carbonate in conversion reactions. Here we report the reversible conversion reaction from copper to Cu2CO3(OH)2, where the copper electrode comprising K2CO3and KOH solid is self‐sufficient with anion‐charge carriers. This electrode dissociates and associates K+ions during battery charge and discharge. The copper active mass and the anion‐bearing cathode exhibit a reversible capacity of 664 mAh g−1and 299 mAh g−1, respectively, and relatively stable cycling in a saturated mixture electrolyte of K2CO3and KOH. The results open an avenue to use carbonate as a charge carrier for batteries to serve for the consumption and storage of CO2.
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Reversible Copper Cathode for Nonaqueous Dual‐Ion Batteries
Abstract Most reported cathodes of nonaqueous dual‐ion batteries (DIBs) host anions via insertion reactions. It is necessary to explore new cathode chemistry to increase the battery energy density. To date, transition metals have yet to be investigated for nonaqueous DIBs, albeit they may offer high capacity in anodic conversion reactions. Here, we report that bulk copper powder exhibits a high reversible capacity of 762 mAh g−1at 3.2 V vs. Li+/Li and relatively stable cycling in common organic electrolytes. The operation of the copper electrode is coupled with the transfer of anion charge carriers. An anion exchange membrane separator is employed to prevent Cu2+from crossing from the catholyte to the anode side. We designed an unbalanced electrolyte with a more concentrated anolyte than a catholyte. This addresses the concentration overpotential ensued during charge and facilitates the high specific capacity and enhanced reversibility. This finding provides a promising direction for high‐energy DIBs.
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- Award ID(s):
- 2215645
- PAR ID:
- 10380262
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 61
- Issue:
- 47
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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