Investigation of the Gas-Diffusion-Electrode Used as Lithium/Air Cathode in Non-aqueous Electrolyte and the Importance of Carbon Material Porosity

Journal Article · Fri Apr 02 04:00:00 EDT 2010 · Journal of Power Sources

OSTI ID:1040391

Qu, D; Yang, X; Tran, C

The gas-diffusion-electrode used in a Li-air cell has been studied in a unique homemade electrochemical cell. Three major obstacles for the development of a feasible Li-air system were discussed with a focus on the development of a functional gas-diffusion-electrode in non-aqueous electrolytes and the way of avoiding the passivation of gas-diffusion-electrodes caused by the deposition of the reduction products. It is the first time that the importance of establishing the 3-phase electrochemical interface in non-aqueous electrolyte is demonstrated by creating air-diffusion paths and an air saturated portion for an air cathode. A model mechanism of electrode passivation by the reaction products was also proposed. Lithium oxides formed during O{sub 2} reduction tend to block small pores, preventing them from further utilization in the electrochemical reaction. On the other hand, lithium oxides would accumulate inside the large pores during the reduction until the density of oxides becomes high enough to choke-off the mass transfer. Carbon materials with a high surface area associated with larger pores should be selected to make the gas-diffusion-electrode for Li-air battery. For the first time, a near linear relationship between the capacity of GDE in a non-aqueous electrolyte and the average pore diameter was demonstrated, which could be used to estimate the capacity of the GDE quantitatively.

• Research Organization: BROOKHAVEN NATIONAL LABORATORY (BNL)
• Sponsoring Organization: USDOE EE OFFICE OF ENERGY EFFICIENCY & RENEWABLE ENERGY (EERE)
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1040391
• Report Number(s): BNL--90696-2010-JA; VT0301010
• Journal Information: Journal of Power Sources, Journal Name: Journal of Power Sources Journal Issue: 7 Vol. 195; ISSN JPSODZ; ISSN 0378-7753
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
36 MATERIALS SCIENCE
CAPACITY
CARBON
CATHODES
DEPOSITION
ELECTROCHEMICAL CELLS
ELECTRODES
ELECTROLYTES
FUNCTIONALS
LITHIUM OXIDES
MASS TRANSFER
OXIDES
PASSIVATION
POROSITY
SURFACE AREA