Review—Recent Research Progress in Surface Modification of LiFePO₄Cathode Materials

Abstract

The olivine structure lithium iron phosphate (LiFePO 4 ) is considered as one of the promising lithium ion batteries cathode materials for its high theoretical specific capacity, excellent reversibility, thermal stability, environmental friendliness, and low cost. However, the application of LiFePO 4 in vehicle power battery was hindered by its poor electronic and ionic conductivity. To solve these problems, various strategies, including surface coating, element doping, and particle size reduction were proposed. In this review, we summed up some recent researches on surface modification of LiFePO 4 and explained the mechanisms of modification. Moreover, the defects and advantages of these modification methods were discussed. Finally, an outlook for the surface modifications of LiFePO 4 cathode materials was given. Since the SONY corporation developed the first generation of commercial lithium-ion batteries in the 1990s, lithium-ion battery has been widely applied in various electronic equipment, such as a carrier of energy storage and conversion.1 In particular, the great development has been made for applications of lithium ion battery in vehicle power.2-6 As the most expensive component of lithium ion battery, cathode materials achieve much attention also for its strong effects on battery capacity, cycle life, and security. Compared with conventional cathode materials, such as LiCoO 2 , LiNiO 2 , and LiMn 2 O 4 , LiFePO 4 is a promising cathode material for rechargeable batteries used for hybrid electric vehicles and bare electric vehicles for its high theoretical capacity (170 mAhg −1 at room temperature), long cycle ability, excellent thermal stability, environmental friendliness, and low cost. [7][8][9]

Electrode Composite LiFePO4@Carbon: Structure and Electrochemical Performances

“…However, many researches have pointed out that the drawbacks are hindered by low electronic conductivity and sluggish Li transportation; therefore, the bulk LiFePO 4 electrode usually shows poor capacity retention during cycling test at both of monorate capability and high-rate capability [8][9][10][11][12]. To overcome these drawbacks, the strategies have been considered commonly as designing the nanostructure and coating carbon.…”

Modification of Cation-Exchange Membranes with Polyelectrolyte Multilayers to Tune Ion Selectivity in Capacitive Deionization

“…As a result, the relative adsorption rate of each type of cation changes as well, indicating that the selectivity can be time-dependent, which refers to the variation in ion selectivity during electrosorption, as already described in the literature. 10 , 39 , 68 , 69 The time where the maximum selectivity value was observed (∼220 s) was abbreviated as t s . At t s , while CMX-PEM adsorbed more Na + compared to Mg 2+ , CMX and CIMS showed the opposite trend during adsorption steps ( Figure 4 A–C).…”

Preparation of hierarchical LiNixCoyMnzO2 from solvothermal [NixCoyMnz](OH)2 via regulating the ratio of Ni, Co, and Mn and its excellent properties for lithium‐ion battery cathode

“…The ternary material has the characteristics of becoming a new generation of high-energy lithium-ion battery electrode materials, and comparing with the strong toxicity of LiCoO 2 , the difficulties in the synthesis of LiNiO 2 , and the lower conductivity of LiMn 2 O 4 and LiFePO 4 . [12][13][14][15] It has been reported in the literature that Ismael et al synthesized the LiNi 0.2 Mn 0.2 Co 0.6 O 2 phase by the combustion method, and the discharge capacity of LiNi 0.2 Mn 0.2 Co 0.6 O 2 positive electrode in the voltage range of 2.7~4.3 V was 160 mAh/g. The corresponding lithiumion polarization was also the lowest.…”