Ameliorating Interfacial Ionic Transportation in All-Solid-State Li-Ion Batteries with Interlayer Modifications

Li-ion batteries (LIBs) are a class of electrochemical energy storage devices widely adapted for their versatile use. Commercialized liquid electrolyte-based batteries are developing various issues like explosions, limited energy density, and leakage. All-solid-state batteries (ASSBs) with Li-ion-containing solid electrolytes (SEs) can be a solution to these shortcomings. However, assembling ASSBs is a challenge due to the high interfacial resistance between the electrodes and SEs. In the current Review, we addressed the rising concern over the interfacial deterioration leading to high charge-transfer resistance. A comprehensive discussion on the addition of buffer layers between the SE and electrodes is presented to improve interfacial stability. From polymer layers containing Li-salts with and without supporting fillers to amorphous oxides and metal coating, the interlayers ameliorate the ionic transport. Mutual compression and cosintering of SEs and electrodes can make a compact interface. Finally, the influence of morphology at the contacting surfaces is discussed.