Primary lithium-sulfur dioxide (Li-SO₂) batteries composed of a carbon cathode, a lithium anode and an organic electrolyte containing sulfur dioxide (SO₂) in an organic solvent were presented in the late 1960s and are mainly used in defense applications.¹ Recently, rechargeable Li-SO₂ batteries with high energy density have been demonstrated.^2-3 The technological breakthrough came from innovative electrolyte systems and nanostructured carbon cathodes. In general, a highly conductive liquid inorganic electrolyte such as LiAlCl₄×xSO₂ has been used.

To date, however, the influence of the electrolyte composition on the electrode reaction of SO₂ has not been explored. In this study, the electrochemical properties of Li-SO₂ rechargeable batteries are examined in various electrolyte solutions. In addition, the relation between carbon loading and SO₂ utilization is intensively investigated.

Acknoledgments

This study was supported by the Energy Efficiency and Resources Core Technology Program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), the financial resources granted from the Ministry of Trade, Industry and Energy, Republic of Korea (No. 20132020000260).

References

1. W. F. Meyers, B. Bell, J. W. Simmons, U.S. Patent 3,423,242 (1969).

2. G. Jeong, H. Kim, J. H. Park, J. Jeon, X. Jin, J. Song, B.–R. Kim, M.-S. Park, J. M. Kim and Y.-J. Kim, Energy Environ. Sci., 8 (2015) 3173.

3. H.-D. Lim, H. Park, H. Kim, J. Kim, B. Lee, Y. Bae, H. Gwon and K. Kang, Angew. Chem., 127 (2015) 9799.