Using a MOF of Wetted Quasi [Zn4O(bdc)3] as Both the Battery Separator and the Electrolyte to Prepare All-Solid-State Batteries of Both ASS-LTO/Li and ASS-Gr/Li

For the first time, a well-defined all-solid-state lithium battery (denoted as ASS-LTO/Li) assembled by an electrode of lithium titanate (Li4Ti5O12, LTO), a metal-organic framework (MOF) of wetted quasi [Zn4O(bdc)3] and a metallic lithium foil is prepared in this work, in which the wetted quasi [Zn4O(bdc)3] is not only employed as a separator but also used as the solid-state electrolyte. The initial charge and discharge capacities of the as-prepared ASS-LTO/Li at 0.2 C are as high as 187.4 and 286.4 mAh·g−1, respectively, corresponding to a Coulombic efficiency of about 65.4%. More importantly, the discharge capacity of ASS-LTO/Li after 100 cycles at 1 C is still as high as 125 mAh·g−1. After a thorough characterization, the greatly attenuated CV peak area, the evidently increased charge transfer resistance, as well as the decomposition of the quais [Zn4O(bdc)3] during cycling, are analyzed to be the main reasons providing the ASS-LTO/Li with an evident decay of the electrochemical performance in the long-term test of 100 cycles at 1 C. An all-solid-state battery (denoted as ASS-Gr/Li) that is constructed by a pure graphite electrode (abbreviated as Gr), a wetted quasi [Zn4O(bdc)3], and a metallic lithium foil is also prepared in this work. The initial discharge capacity of ASS-Gr/Li at 0.2 A·g−1 is about 169 mAh·g−1, a value evidently lower than the theoretical value of graphite (372 mAh·g−1). The discharge capacity of ASS-Gr/Li at 1.0 A·g−1 is about 24 mAh·g−1, which decreases to about 12 mAh·g−1 after 100 cycles. Although the battery performances of the above two newly developed batteries are poor as compared to the state-of-the-art all-solid-state lithium batteries reported recently, this work sheds light on a novel approach for the further exploration of all-solid-state lithium battery.