A double-layer hollow structure high-rate lithium-rich manganese-based positive electrode material and preparation method thereof

Abstract

The invention discloses a high multiplying power lithium-enriched manganese-based anode material with a double-layer hollow structure and a preparation method thereof. The chemical formula of the anode material is aLi2MnO3.(1-a)LiMO2, wherein 0.1<=a<1; M=Mn1-x-yNixCoy, 0<=x<=0.5, and 0<=y<=0.5. The method for preparing the high multiplying power lithium-enriched manganese-based anode material comprises the steps of adopting a coprecipitation method to obtain a manganese-nickel-cobalt ternary carbonate precursor with a solid structure, calcining the manganese-nickel-cobalt ternary carbonate precursor with the solid structure, obtaining a manganese-nickel-cobalt ternary oxide precursor with a core-shell structure, evenly mixing and calcining the manganese-nickel-cobalt ternary oxide precursor with the core-shell structure and lithium salt, and obtaining the layered lithium-enriched manganese-based anode material with the double-layer hollow structure. The high multiplying power lithium-enriched manganese-based anode material is simple in process, the performance is improved obviously and reliably, the prepared high multiplying power lithium-enriched manganese-based anode material with the double-layer hollow structure has a large specific capacity and excellent multiplying power and cycle performance, and the problem that the high capacity and the high multiplying power property cannot be achieved simultaneously is solved.

Description

technical field [0001] The invention belongs to the technical field of material synthesis, and relates to a lithium-ion battery positive electrode material and a preparation method thereof, in particular to a high-rate lithium-rich manganese-based positive electrode material with a double-layer hollow structure and a preparation method thereof. Background technique [0002] Lithium-ion batteries are superior to other secondary batteries because of their high energy density, high output voltage, and low environmental pollution. They have become ideal power sources for portable electronic devices. They have also shown great potential in the fields of electric vehicles and energy storage power stations. Application prospect. At the same time, people's growing living needs put forward higher requirements on the specific capacity, cycle performance, rate performance, safety performance, and cost of lithium-ion battery modules. [0003] The cathode material is currently the only ...

AI Technical Summary

Problems solved by technology

Although ternary layered cathode materials reduce material cost and toxicity, and significantly improve the safety of materials, the actual specific capacity of these layered structure materials has not made a major breakthrough; three-dimensional tunnel structure spinel cathode materials and polyanion cathode materials Although they have high safety performance, the theoretical specific capacity of these materials is far from meeting the performance requirements of high specific energy lithium-ion batteries for cathode materials.

However, lithium-rich manganese-based cathode materials have low electrical conductivity, poor high-current discharge and high-rate performance, and rapid capacity decay during cycling. These shortcomings have become technical bottlenecks that limit the application of lithium-rich manganese-based cathode materials.

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