Hierarchical Design in LiMn2O4 Particles for Advanced Hybrid Aqueous Batteries

Recently, tremendous research has been done on fast-charged Li-ion batteries for use in vehicles. If the Li-ion cathode could be fully charged at 10 C or in 6 min, this charging time would be the same magnitude as the filling period of the hydrogen-fuelcell vehicles or the diesel-filling time on trucks. This current obstacle is solved in this work at an industrial level, using a completely green method without the need for any extra chemical product. We focus on the gentle exfoliating secondary particles of the commercial LiMn2O4 to deliver mixtures of submicron size secondary and primary particles without severe amorphization of the crystalline surface. The products are characterized by XRD and SEM. The electrochemical activity of this submicron LiMn2O4 is evaluated as the cathode in a 5 A.h scale rechargeable hybrid aqueous battery (i.e., 20,000 times higher than a typical laboratory coin cell). High capacity values of 124.1 mA h g(-1) after 100 cycles under 0.2 C and 89.3 mA h g(-1) after 1000 cycles at 10 C with no obvious capacity fading are realized. The mechanism is explained in detail, which includes quantitative contributions of pseudocapacity and intercalation.

Automated summary

This study successfully addressed the industrial-level fast charging Li-ion batteries, using a green approach to demonstrate the high electrochemical activity of LiMn2O4 in hybrid aqueous batteries, achieving excellent capacity values without obvious fading.