A New Approach to Carbon Dioxide Utilization: The Carbon Molten Air Battery

Tuesday, 30 May 2017: 17:40
Grand Salon B - Section 12 (Hilton New Orleans Riverside)
S. Licht (The George Washington University), M. Johnson (George Washington University), M. J. Lefler (The George Washington University), and J. Vicini (George Washington University)
As the levels of carbon dioxide (CO2) increase in the Earth’s atmosphere, the effects on climate change become increasingly apparent. With the demand to reduce our dependence on fossils fuels and lower our carbon emissions, a transition to renewable energy sources is necessary. Cost effective large-scale electrical energy storage must be established for renewable energy to become a sustainable option for the future. We've previously shown that carbon dioxide can be captured directly from the air at solar efficiencies as high as 50%, and that carbon dioxide associated with cement formation and the production of other commodities, such as ammonia and iron, can be electrochemically avoided in the STEP process.1-6

The carbon molten air battery, presented by our group in late 2013,7 as one of a new class of rechargeable “molten air” batteries that utilize a molten electrolyte and a quasi-reversible air electrode,7-10 is attractive due to its scalability, location flexibility, and construction from readily available resources, providing a battery that can be useful for large scale applications, such as the storage of renewable electricity.

Uncommonly, the carbon molten air battery can utilize carbon dioxide directly from the air:7,11-18

charging: CO2(g) → C(solid) + O2(g) (1)

discharging: C(solid) + O2(g) → CO2(g) (2)

More specifically, in a molten carbonate electrolyte containing added oxide, such as lithium carbonate with lithium oxide, the 4 electron charging reaction eq. 1 approaches 100% faradic efficiency and can be described as the following two equations:

O2-(dissolved) + CO2(g) → CO32-(molten) (1a)

CO32-(molten) → C(solid) + O2(g) + O2-(dissolved) (1b)

Using carbon formed directly from the CO2in our earth’s atmosphere, the carbon molten air battery is a viable system to provide large-scale energy storage.


1Licht, STEP generation of energetic molecules: A solar chemical process to end anthropogenic global warming,

J. Phys. Chem., C, 113, 16283 (2009).

2Licht, Efficient Solar-Driven Synthesis, Carbon Capture, and Desalinization, STEP: Solar Thermal Electrochemical Production of Fuels, Metals, Bleach

Advanced Materials, 47, 5592 (2011).

3Licht, Wu, Hettige, Wang, Lau, Asercion, Stuart, STEP Cement: Solar Thermal Electrochemical Production of CaO without CO2emission,

Chemical Communications, 48, 6019 (2012).

4Licht, Cui, Wang, Li, Lau, Liu, Ammonia synthesis by N2 and steam electrolysis in molten hydroxide suspensions of nanoscale Fe2O3,

Science, 345, 637 (2014).

5Cui,  Zhang, Liu, Liu, Xiang,  Liu, Xin, Lefler, Licht, Electrochemical synthesis of ammonia directly from N2 and water over iron-based catalysts supported on activated carbons,

Green Chemistry, 2 DOI: 10.1039/C6GC02386J (2016).

6Li, Wang, Licht, Sustainable Electrochemical Synthesis of large grain or catalyst sized iron,

J. Sustainable Metallurgy, 2, 405 (2016).

7Licht, Cui, Stuart, Wang, Lau, Molten Air Batteries - A new, highest energy class of rechargeable batteries,

Energy & Environmental Science, 6, 3646 (2013).

8Liu, Li, Cui, Liu , Hao, Guo, Pe. Xu, Licht, Critical advances for the iron molten air battery: A new lowest temperature, rechargeable, ternary electrolyte domain,

J. Materials Chemistry, A, 3, 21039 (2015); ibid, 2, 10577 (2014).

9Cui,  Xin, Liu,  Liu,  Hao,  Guo, Licht, Improved cycle iron molten air battery performance using a robust fin air electrode,”

J. Electrochem. Soc., in press (2016).

10Cui, Xiang, Liu,  Xin, Liu Licht, A novel rechargeable zinc-air battery with molten salt electrolyte,

J. Power. Sources, in press (2017).

11Licht, Cui, Wang, STEP Carbon Capture: the barium advantage,

J. CO2 Utilization, 1, 58 (2013).

12Ren, Li, Lau, Gonzalez-Urbina, Licht, One-pot synthesis of carbon nanofibers from CO2,

Nano Letters, 15, 6142 (2015).

13Ren, Lau, Lefler, S. Licht, The minimum electrolytic energy needed to convert carbon dioxide by electrolysis in carbonate melts,

J. Phys. Chem., C, 119, 23342 (2015).

14Licht, Douglas, Ren, Carter, Lefler, Pint, Carbon Nanotubes Produced from Ambient Carbon Dioxide for Environmentally Sustainable Lithium-Ion and Sodium-Ion Battery Anodes,

ACS Central Science, 2, 162 (2015).

15Ren, Lau, Lefler, Licht, The minimum electrolytic energy needed to convert carbon dioxide by electrolysis in carbonate melts,

J. Phys. Chem., C, 119, 23342 (2015).

16Lau, Dey, Licht, Thermodynamic assessment of CO2to carbon nanofiber transformation for carbon sequestration in a combined cycle gas or a coal power plant,

Energy Conservation and Management, 122, 400 (2016).

17Wu, Li, Ji, Liu, Li, Yuan, Zhang, Ren, Lefler, Wang, Licht, One-Pot Synthesis of Nanostructured Carbon Material from Carbon Dioxide via Electrolysis in Molten Carbonate Salts,

Carbon, 6, 27760 (2016).

18Ren, Licht, Tracking airborne CO2mitigation and low cost transformation into valuable carbon nanotubes,

Scientific Reports, 106, 208 (2016).

Figure: Variations of the Molten Battery.