项目来源

国家重点研发计划(NKRD)

项目主持人

周亮

项目受资助机构

四川绿鑫电源科技有限公司

项目编号

2018YFB0104202

立项年度

2018

立项时间

未公开

项目级别

国家级

研究期限

未知 / 未知

受资助金额

0.15万元

学科

新能源汽车

学科代码

未公开

基金类别

未公开

关键词

硅 ; 锂金属 ; 锂离子电池 ; 负极 ; silicon ; lithium metal ; lithium ion battery ; anode

参与者

未公开

参与机构

武汉理工大学

项目标书摘要：目前车用动力电池的能量密度受电极材料比容量的限制，仍未能突破250 Wh/kg的能量密度瓶颈，难以满足电动汽车等应用领域的高能量密度需求。金属锂和硅负极具有高容量、低电位等突出优势有望替代传统的石墨电极。然而，金属锂负极容易生长锂枝晶并导致低库伦效率、短循环寿命、高安全隐患的难题而硅负极材料也具有首次库伦效率低，体积膨胀严重等缺陷。在硅负极材料设计方面，本课题将在已有成果基础上，进一步优化溶胶—凝胶与镁热还原等工艺技术与工程化装置，开展Si-C复合材料的宏量制备技术研究。重点研究材料颗粒尺寸、颗粒均匀性、还原工艺对Si-C 复合材料电化学性能的影响，确定高性能Si-C 复合材料的宏量制备技术，并成功合成了一系列性能优异的硅基和硅氧化物基锂离子电池负极材料。在锂金属负极方面，本课题采用反应合成法制备了三维LiB纤维骨架支撑的Li-LiB复合材料，通过硼含量的改变及热处理工艺的优化，调控LiB纤维直径、纤维密度、纤维含量，从而控制孔隙率、孔径大小及孔结构。构筑Li-LiB复合带材，实现锂的定向生长与溶解，解决锂负极的枝晶生长问题及其伴随的库仑效率低、循环寿命短、安全隐患高的问题，为锂金属电池的产业化应用提供理论依据和技术支撑。

Application Abstract: Limited by the specific capacity of electrode materials,it’s difficult for lithium-ion batteries to achieve an energy density beyond 250 Wh/kg,which can’t meet the increasing energy density requirements of electric vehicles.Lithium metal and silicon-based anodes have the advantages of high capacity and low potential,which have potential to replace traditional graphite anode.However,lithium metal anodes tend to generate lithium dendrites,leading to low Coulomb efficiency,short cycle life,and safety issues.For silicon-based anode materials,they usually suffer from deficiencies such as low initial Coulomb efficiency and large volume expansion.In the aspect of silicon-based anode materials,this project optimized the process technology and engineering equipment for sol-gel synthesis and magnesiothermic reduction,making the large-scale production of Si-C composite anode materials feasible.The effects of particle size,particle uniformity,and reduction process on the electrochemical performances of Si-C anode materials have been systematically studied.The project develops a technology for the mass production of high-performance Si-C anode materials.A series of silicon and silicon oxide-based lithium-ion battery anode materials with excellent electrochemical performances have been synthesized.For the lithium metal anodes,this project prepared a three-dimensional LiB fiber skeleton-supported Li(Li-LiB)composite material through the reaction synthesis method.By tuning the B content and optimizing the heat treatment process,the LiB fiber diameter,fiber density,and fiber content can be adjusted,and the porosity,pore size,and pore structure of the Li-LiB composite material can be controlled.Through fabricating Li-LiB composite strips with directional lithium growth and dissolution,the dendrite growth,low Coulomb efficiency,short cycle life,and safety issues of lithium metal anodes can be tackled.This project can provide theoretical basis and technical support for industrial application of lithium metal anodes.

项目受资助省

四川省