Carbon dioxide assist for non-aqueous sodium–oxygen batteries

• Published in: Electrochemistry communications 2013-02, Vol.27, p.59-62
• Main Authors: Das, Shyamal K., Xu, Shaomao, Archer, Lynden A.
• Format: Article
• Language: English
• Subjects: Applied sciences; Direct energy conversion and energy accumulation; Electrical engineering. Electrical power engineering; Electrical power engineering; Electrochemical conversion: primary and secondary batteries, fuel cells; Exact sciences and technology; Magnesium–air battery; Sodium–air battery
• ISSN: 1388-2481; 1873-1902
• DOI: 10.1016/j.elecom.2012.10.036

We report a novel non-aqueous Na–air battery that utilizes a gas mixture of CO2 and O2. The battery exhibits a high specific energy of 6500–7000Whkg−1 (based on the carbon mass) over a range of CO2 feed compositions. The energy density achieved is higher, by 200% to 300%, than that obtained in pure oxygen. Ex-situ FTIR and XRD analysis reveal that Na2O2, Na2C2O4 and Na2CO3 are the principal discharge products. The Na–CO2/O2 and Mg–CO2/O2 battery platforms provide a promising, new approach for CO2 capture and generation of electrical energy. ► We report a novel sodium–CO2/O2 battery that uses a mixture of CO2 and O2 as fuel. ► Na–CO2/O2 batteries provide a platform for CO2 capture and conversion. ► Moderate levels of CO2 in an O2 feed produce up to 300% enhancement in performance. ► Postmortem studies reveal carbonates and oxalates are dominant discharge products. ► A mechanism is proposed for the electrochemical reactions in Na–CO2/O2 batteries.