In situ construction of cubic 3D Li+ channels enabling stable electrochemical topology in a Li-rich layered solid-state oxide-based lithium-ion battery

Solid-state Li-ion batteries (SSLIBs) are expected to become the next-generation energy storage devices due to their high energy density and safe reliability. While the use of conventional cathodes in SSLIBs clearly cannot meet the increasing energy density demands of electric vehicles (EVs). A Li-rich Mn-based oxide (LRMO) has been extensively studied in liquid-state electrolytes (LEs) due to its higher capacity density (≥250 mAh g−1). However, the further application of LRMO in SSLIBs is rarely reported due to its extremely low electronic conductivity (10−11 S cm−1) and gas evolution at high voltage (≥4.3 V). This work demonstrates a novel in situ synthetic strategy for preparing enhanced cubic 3D Li+ channel buffered LRMO cathodes packaged with Li6.75La3Zr1.75Nb0.25O12 (LLZNO) solid electrolyte (SE) for use in SSLIBs. The stable electrochemical topology contributes to good initial discharge capacities (IDC, 0.1 C, 183.1 mAh g−1) and stable cycling retention (0.1 C, 300 cycles, 73.4%) at room temperature (RT, 25 °C). In situ tests analysis and first-principles calculations (DFT) results demonstrated the promising industrial prospects for using the LZM cathode in SSLIBs.