Since the industrial Revolution,the rapid development of science and technology has continuously enriched people's life.At the same time,fossil energy(oil,coal,natural gas,etc.)consumption and carbon dioxide emissions increase year by year,resulting in global warming and critical ecological environment issues.Fuel vehicles are the main source of oil consumption.In order to help the implementation of carbon peaking and carbon neutrality goals,new energy vehicles are developing rapidly and their sales are increasing year by year.As the power source of new energy vehicles,the power batteries have attracted much attention.It is very important to develop the power batteries with low price,abundant resources and excellent safety for new energy vehicles.At present,lithium iron phosphate(LiFePO4)and layered lithium nickel cobalt manganese oxides are widely used as cathode materials for lithium-ion batteries of hybrid electrical vehicle(HEV)and electric vehicle(EV).A few years ago,due to the impact of state subsidies,shipments of LiFePO4 almost ceased to increase because of its lower energy density than ternary cathode materials that have been surging ahead and dominating the market of new energy vehicles.With the withdrawal of subsidy policy,LiFePO4,as an olivine-structured compound,has regained favor because of its unprecedented combinations properties such as low cost,high safety and environmental friendliness.Meanwhile,the blade batteries,also known as LiFePO4,greatly improves the energy density significantly,benefiting to technological advances in structural design.In 2021,shipments of LiFePO4 cathode materials reversed the trend,reaching 470,000 tons.However,LiFePO4 is insufficient to meet today's high-power demand due to its low electronic conductivity(＜10-9 S cm1)and low lithium-ion diffusion coefficient(10-14cm2s-1～10-16cm2s-1).Based on the market demand for fast charging-discharging of new energy vehicles,it is urgent to improve the electrochemical performance of LiFePO4.Current strategies mainly include control of crystal size and orientation by improving conditions,surface coating,doping,defect control,etc.In this review,based on the composition and working principle of lithium-ion battery and combined with the crystal structure characteristics and charge-discharge mechanism of LiFePO4,the progress in high-performance olivine-structured lithium iron phosphate is deeply discussed,and the future research direction and development trend of LiFePO4 are put forward.
万方数据
维普
