Journal of Membrane Science, Vol.555, 169-176, 2018
A sandwich structure polymer/polymer-ceramics/polymer gel electrolytes for the safe, stable cycling of lithium metal batteries
The highest specific capacity (3860 mAh g(-1)) and minimum negative electrochemical potential make lithium metal as a perfect candidate for next-generation high energy battery. However, the safety issue caused by the lithium dendrite growth hinders the practical use of lithium metal battery. Herein, a polymer/polymer-ceramic/polymer sandwich structure electrolytes (SWEs) are proposed to address this problem by combing the advantage of inorganic and gel-type polymer electrolytes. The flexible SWEs show a high ionic conductivity (similar to 3.01 x10(-3) S/cm) at room temperature, high lithium transference number (t(Li+) = 0.74), and stable electrochemical widows up to 5.0 V. Furthermore, the SWEs can effectively prevent lithium dendrites in a symmetric Li/SWEs/Li test during charge and discharge with a current density of 1 mA/cm(2) for 240 h at room temperature. Meanwhile, the lithium metal battery assembled using LiCoO2/SWEs/Li exhibits the high cycling capacity of -110 mAh g(-1) at 2 C over 100 cycles and fascinating rate performance (144 mAh g(-1)@ 1 C and 98 mAh g(-1)@ 5 C) at room temperature. Our work provides a new design paradigm to exploit the advanced electrolyte for lithium metal battery and flexible devices.