Wednesday, 1 June 2016: 16:40
Indigo Ballroom E (Hilton San Diego Bayfront)
I. Villaluenga (Lawrence Berkeley National Laboratory), K. Wujcik (University of California, Berkeley), W. Tong, D. Devaux (Lawrence Berkeley National Laboratory), D. H. C. Wong (University of North Carolina at Chapel Hill), J. M. DeSimone (North Carolina State University), and N. P. Balsara (Lawrence Berkeley National Laboratory)
Electrolytes used in lithium-ion batteries that power personal electronic devices and electric vehicles comprise lithium salts dissolved in flammable organic liquids. Catastrophic battery failure often begins with the electrolyte decomposition and combustion. Mixtures of liquids and salts have additional limitations. The passage of current results in an accumulation of salt in the vicinity of one electrode and depletion close to the other electrode, because only the cation participates in the electrochemical reactions. These effects are minimized in the case of single-ion-conducting-solid electrolytes due to the absent of concentration polarization and the limited solubility and slow diffusion (1). Therefore, non-flammable single-ion-conducting solid electrolytes have the potential to dramatically improve safety and performance of lithium batteries (2,3). Solid electrolytes such as inorganic sulfide glasses (Li
2S–P
2S
5) are single-ion-conductors with high shear moduli (18-25 GPa) and high ionic conductivity (over 10
−4S/cm) at room temperature (4,5). However, these materials, on their own, cannot serve as efficient electrolytes as they cannot adhere to moving boundaries of the active particles in the battery electrode as they are charged and discharged.
In this study, we describe hybrid single-ion-conducting electrolytes based on inorganic sulfide glasses and perfluoropolyether polymers for lithium batteries. Herein, it is demonstrated that hybrid electrolytes provide a compelling alternative to the traditional glass, ceramic, or polymer battery electrolytes. These electrolytes present high transference numbers, unprecedented ionic conductivities at room temperature, excellent electrochemical stability, and limit the dissolution of lithium polysulfides. The results in this work represent a significant step toward addressing the challenges of enabling the next generation cathodes such as lithium nickel manganese cobalt oxide and sulfur.
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[1] J.M. Tarascon, M. Armand, Nature, 414 (2001) 359-367.
[2] R. Bouchet, et al., Nature Materials, 12 (2013) 452-457.
[3] N. Kamaya, et al., Nature Materials, 10 (2011) 682-686.
[4] Z. Liu, et al., Journal of the American Chemical Society, 135 (2013) 975-978.
[5] A. Sakuda, A. Hayashi, Y. Takigawa, K. Higashi, M. Tatsumisago, Journal of the Ceramic Society of Japan, 121 (2013) 946-949.
