The electrochemical performances of MnFe_PBA synthesized at ambient and −10°C. (A) Cyclic voltammetry (CV) curves of MnFe_PBA_RT w/o EG, MnFe_PBA_RT w EG, and MnFe_PBA_Cryo_−10°C with their respective polarization voltages. (B) Cycling performances of MnFe_PBA at room temperature and cryo-synthesis at the current densities of 500 mA g⁻¹. (C) Rate performance of MnFe_PBA_Cryo_−10°C at current densities from 500 to 1500 mA g⁻¹. (D) Charge-discharge curves of MnFe_PBA_Cryo_−10°C at current densities from 500 to 1500 mA g⁻¹. (E) Long-term cycling performances of MnFe_PBA_Cryo_−10°C at the current densities of 2000 mA g⁻¹. (F) Comparison of the capacity retention in this work with previously reported PBAs.