Synthesis and electrochemical performance of Sn-doped LiNi0.5Mn1.5O4 cathode material for high-voltage lithium-ion batteries

Abstract

LiNi0.5Mn1.5−xSnxO4 (0 ≤ x ≤ 0.1) cathode materials with uniform and fine particle sizes were successfully synthesized by a two-step calcination of solid-state reaction method. As the cathode materials for lithium ion batteries, the LiNi0.5Mn1.48Sn0.02O4 shows the highest specific capacity and cycle stability. In the potential range of 3.5-4.9 V at room temperature, LiNi0.5Mn1.48Sn0.02O4 composite material shows a discharge capacity of more than 117 mA h g −1 at 0.1 C, while the corresponding discharge capacity of undoped LiNi0.5Mn1.5O4 is only 101 mA h g −1 . Moreover, in cycle performance, all the LiNi0.5Mn1.5−xSnxO4 (0 ≤ x ≤ 0.1) samples show better capacity retention than the undoped LiNi0.5Mn1.5O4 at 1 C rate after 100 cycles. Especially, for the LiNi0.5Mn1.5O4, the discharge capacity after 100 cycles is 90 mA h g −1 , while the corresponding discharge capacities of the undoped LiNi0.5Mn1.5O4 is only 56.1 mA h g −1 . The significantly enhanced DLi + and the enlarged electronic conductivity make the Sn-doped spinel LiNi0.5Mn1.5O4 material present even more excellent electrochemical performances. These results reveal that Sn-doping is an effective way to improve electrochemical performances of LiNi0.5Mn1.5O4.

Enhanced electrochemical property of FePO4-coated LiNi0.5Mn1.5O4 as cathode materials for Li-ion battery

“…The calculated lithium-ion diffusion coefficient values of FePO 4 (0, 0.5 wt%, 1 wt%, and 3 wt%)-coated LiNi 0.5 Mn 1.5 O 4 cathodes are 1.05 Â 10 À16 , 1.07 Â 10 À16 , 8.71 Â 10 À15 and 1.32 Â 10 À15 cm 2 s À1 , respectively. The relative low diffusion coefficients of LiNi 0.5 Mn 1.5 O 4 in this work is closely related to the synthesis method, particle size and test methods [38], which are in accordance with the values reported by Hao et al [52] for the same test method. Obviously, FePO 4 coated LiNi 0.5 Mn 1.5 O 4 cathodes show higher lithium diffusion coefficient than that of pristine one, and the increased lithium-ion diffusion coefficient is mainly from the FePO 4 coating.…”

Structure design and mechanism analysis of silicon anode for lithium-ion batteries

“…Rechargeable lithium-ion batteries (LIBs), as one of the energy storage technologies, are the key part of the contemporary energy system which is closely coupled with renewable energy generation, transmission and utilization [1][2][3][4]. Meanwhile, due to the high energy density, long lifespan and environmental friendliness, LIBs have been highly developed over the past decades and widely used in our daily life including portable electronics, electrical transportation, and even grid energy storage [5][6][7].…”

Synthesis of LiNi0.5Mn1.5O4 via Ammonia‐free Co‐precipitation Method: Insight in the Effects of the Lithium Additions on the Morphology, Structure and Electrochemical properties

“…The lithium ion diffusion coefficient ( D Li+ ) has been further deduced from a sloping straight line in the low‐frequency based on the following equations: …”