All Solid-State Lithium Batteries Assembled with Hybrid Solid Electrolytes

Lithium-ion batteries have rapidly become the dominant power sources for portable electronic devices, electric vehicles and energy storage systems, due to their high energy density and long cycle life [1,2].  However, safety issues still prevent full utilization of these batteries.  One of the most efficient methods to enhance the battery safety is to use solid electrolyte [3-5].  Solid inorganic electrolytes present potential advantages, such as a wide electrochemical stability window, enhanced thermal stability, absence of solvent leakage and high resistance to shocks, which are important safety assets.  However, sheet manufacturing, especially using thin-film technologies for making large-scale batteries, is considered to be difficult because of brittle characteristics of ceramic materials.  In this work, the hybrid solid electrolytes composed of lithium aluminum germanium phosphate (LAGP) and poly(ethylene oxide)(PEO) were prepared in the form of flexible thin film, and their electrochemical properties were investigated.  Their morphological properties studied using SEM, EDS and XRD.  The ionic conductivities and electrochemical stability of hybrid solid electrolytes were much higher than those of PEO-based polymer electrolyte.  All solid-state lithium batteries assembled with hybrid solid electrolyte exhibited high discharge capacity and excellent capacity retention with a coulombic efficiency exceeding 99.5% at 55 ^oC.

References

[1] J. M. Tarascon, M. Armand, Nature 414 (2001) 359.

[2] P. G. Bruce, B. Scrosati, J. M. Tarascon, Angew. Chem. Int. Ed. 47 (2008) 2930.

[3] N. Kamaya, K. Homma, Y. Yamakawa, M. Hirayama, R. Kanno, M. Yonemura, T. Kimiyama, Y. Kato, S. Hama, K, Kawamoto and A. Mitsui, Nat. Mater. 10 (2013) 682.

[4] H. S. Jadhav, M.S Cho, R. S. Kalubrame, J. S. Lee, K. N. Jung, K. H. Shin, C. J. Park, J. Power Sources 241 (2013) 502.

[5] Y. Li, C. A. Wang, H. Xie, J. Cheng, J. B. Goodenough, Electrochem. Commun. 13 (2011) 1289.