3.2v 20ah lifepo4 battery cell.The research and development of special high-nickel cathode materials for "new energy vehicles" has achieved phased progress

People's Daily Online, Beijing, April 5 (Reporter He Yingchun) According to the website of the Ministry of Science and Technology, the 2016 project "Development and Industrialization Technology of High-Specific Energy Power Lithium-ion Batteries" of the National Key R&D Program "New Energy Vehicles" was launched in Gao Breakthrough progress has been made in the research and development of nickel cathode materials.

People's Daily Online, Beijing, April 5 (Reporter He Yingchun) According to the website of the Ministry of Science and Technology, the 2016 project "Development and Industrialization Technology of High-Specific Energy Power Lithium-ion Batteries" of the National Key R&D Program "New Energy Vehicles" was launched in Gao Breakthrough progress has been made in the research and development of nickel cathode materials. It is reported that the project R&D team solved the technical problems of low discharge specific capacity and low first efficiency of high nickel-based materials through basic formula experiments in the first phase, combining precursor controlled crystallization synthesis technology, oxygen-rich atmosphere secondary solid-phase synthesis technology and Key technologies such as formula adjustment and coating technology can increase the degree of oxidation of Ni2+ to Ni3+, reduce the contact between the material surface and the electrolyte, reduce the amount of residual Li on the material surface, and increase the first discharge capacity of high nickel-based materials without increasing the Ni content. Increased to ≥206mAh/g, first effect ≥90%, tap density ≥2.1g/cm3, magnetic impurity content ≤40ppb, pH≤11.7, and has a 20t/month pilot production line. At the same time, in view of the technical problems of difficult continuous gradient preparation of Ni, Co, and Mn elements in the current precursor and poor control of uniformity, the project team used three solutions of Ni, Co, and Mn to prepare separately, and each of them accurately controlled the flow rate through a design program. Entering into the new idea of the reactor, we designed and produced a 100-liter experimental device, compiled the control program, optimized the preparation process parameters, and realized the continuous gradient distribution of the three elements in the precursor from the core to the shell according to an arbitrary curve, thus significantly reducing the The inhomogeneity of the material in terms of volume effect, stress, etc. caused by component mutations can reduce micro-cracks in the particles during the charge and discharge process and improve the capacity retention rate. This method also improves the batch uniformity of the precursor. The synthesized precursor has a secondary spherical structure, controllable particle size and component gradient distribution, and a tap density higher than 1.8g/cm3. The above results lay a good foundation for the fine design of the components and gradient of high-nickel ternary cathode materials and the development of gradient high-nickel cathode materials with high specific capacity and long life.