A novel sheet perovskite type oxides LaFeO₃ anode for nickel-metal hydride batteries

Compared with traditional hydrogen storage alloys, perovskite oxide LaFeO₃ materials are considered as one of the most promising anode materials for nickel-metal hydride batteries owing to their low cost, environmental friendliness, and superior temperature resistance. However, the biggest problem faced by perovskite oxide LaFeO₃ as an anode material for Nickel/metal hydride (Ni-MH) batteries is the low electrical conductivity and poor specific capacity, which is mainly due to the serious agglomeration phenomenon in its structure. To solve the above problems, lamellar LaFeO₃ material with large specific surface area and small particle size has been synthesized by adding N,N-Dimethylformamide (DMF) and polyvinyl pyrrolidone (PVP) inhibitor materials to the precursor. By changing the sintering temperature, the lamellar composite LaFeO₃ material can be controlled. Consequently, the maximum discharge capacity of lamellar LaFeO₃ is up to 372.1 mA h g^–1 at the discharge current density of 60 mA g^–1. Meanwhile, after 100 cycles, the specific discharge capacity of the lamellar LaFeO₃ can still reach 293.1 mA h g^–1, which is much higher than that of 98.5 mA h g^–1 for LaFeO₃. In addition, the kinetics of LaFeO₃ has been investigated and the lamellar LaFeO₃ shows excellent dynamic properties. Notably, the exchange current density I₀ (300 mA g^–1) of the layered LaFeO₃ electrode is higher than that of LaFeO₃ (150 mA g^–1). Overall, this work provides insights into a structure-performance relationship for the further development of high-performance perovskite-type oxide nickel-metal hydride battery anodes.