How to overcome Na deficiency in full cell using P2-phase sodium cathode - A proof of concept study of Na-rhodizonate used as sodium reservoir

JOURNAL OF POWER SOURCES

卷:450

Article

Marelli, Elena¹  Marino, Cyril¹  Bolli, Christoph¹  Villevieille, Claire² 

[1] Paul Scherrer Inst, Electrochem Lab, CH-5232 Villigen, Switzerland

[2] Univ Grenoble Alpes, LEPMI Lab, Grenoble INP, F-38402 St Martin Dheres, France

关键词: Batteries;    Na-ion;    P2 cathode;    Operando X-ray diffraction;    Mass spectroscopy;   

DOI  :  10.1016/j.jpowsour.2019.227617

来源: Elsevier

【 摘 要 】

An organic, cheap and environmental friendly salt, namely disodium rhodizonate Na2C6O6, is tested as Na sacrificial template in a full-cell sodium-ion battery employing a sodium deficient P2 phase, Na0.67Mn0.6Fe0.25Co0.15O2 (NaMFC) as cathode, and a carbonaceous material as counter electrode. As a proof of concept, we demonstrated that the decomposition of the sacrificial organic material leads to enhance the specific capacity in the full-cell system, but the electrochemical results are mitigated by the high irreversibility caused by the side products coming from the sacrificial template decomposition. The mechanism of decomposition of the organic additive as well as its impact on the reaction mechanisms are investigated by online electrochemical mass spectroscopy (OEMS), microscopy and Raman/Infrared vibrational spectroscopy. Additionally, operando X-ray diffraction (XRD) demonstrates that during the oxidation of the disodium rhodizonate, the P2-phase undergoes a re-sodiation, which explains the benefit of Na2C6O6 as Na reservoir.

【 授权许可】

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