A High-Performance Dual-Ion Battery Enabled by Conversion-Type Manganese Silicate Anodes with Enhanced Ion Accessibility

Graphical Conversion-type ultra-small Mn 7 O 8 (SiO 4 ) nanosheet/reduced graphene oxide anodes with enhanced diffusion kinetics are constructed for Li-dual ion batteries (LDIBs) for the first time. The in situ formed Li 4 SiO 4 ionic conductor and the pseudocapacitive contribution endow them with 191 mA h g −1 at 0.5 C and 128 mA h g −1 at 2 C after 150 cycles, realizing the construction of high-performance LDIBs. Limited by the sluggish kinetics of conversion-type anodes from huge diffusion-controlled phase transformation and unsatisfactory capacities of intercalation/alloy-type anodes, the performances of lithium-based dual ion batteries (LDIBs) remain to be promoted. Herein, for the first time, ultra-small manganese silicate (MS) nanosheets anchored on reduced graphene oxides (MSR) with enhanced diffusion kinetics are constructed, realizing the construction of high performance LDIBs on the basis of conversion-type anodes. The ion diffusion rate of MSR is promoted by in situ coating Li 4 SiO 4 ionic conductor on the electrode surface during lithiation process. Simultaneously, the ion diffusion pathways are shortened by partially converting the diffusion-controlled bulk reaction to surface reaction with massive pseudocapacitive contribution. Consequently, the MSR-based LDIB exhibits superior electrochemical performances with discharge capacities of 191 mA h g −1 at 0.5 C and 128 mA h g −1 at 2 C after 150 cycles, exceeding to those of reported LDIBs and benefiting the future electrode design of LDIBs.