SLS/三维转印点阵集流体的力电转换和电阻热响应性能协同调控机制

锂离子电池内部热失控主要由短路、过充和高温引发，是目前其面临的最大安全问题。现有研究采用三维负极集流体抑制锂枝晶生长，从而防止短路，但难以感知并预警过充引起的鼓包变形，无法避免高温环境下的热失控。为此，本项目提出创新思路：在激光选区烧结（SLS）增材制造的磁性点阵基体上三维转印液态金属，得到磁电一体化点阵集流体，其兼具力电转换和电阻热响应性能，从而实现应变传感和高温断路功能。针对“SLS材料与工艺对磁性点阵基体与液态金属界面性能的影响规律”和“集流体力电转换和电阻热响应性能与其材料和结构的关联关系”两个关键科学问题，重点研究集流体的材料/结构设计方法、成形工艺、界面性能、力电转换和电阻热响应性能。本项目有望在磁性基体与液态金属界面结合机理，力电转换和电阻热响应性能协同调控方法方面取得创新成果，为优化磁电一体化点阵集流体的性能，实现锂离子电池安全性可防可控奠定理论基础，具有重要科学意义。

The internal thermal runaway of lithium-ion batteries is primarily ascribed to short circuit, overcharge and high temperature, which is the biggest safety issue faced by lithium-ion batteries at present. In previous studies, three-dimensional anode current collectors have been adopted to inhibit the growth of lithium dendrite and thus prevent short circuit. However, it is difficult for this method to sense and warn the bulge deformation caused by overcharge or avoid the thermal runaway in a high-temperature environment. Therefore, this project proposes an innovative idea that magnetoelectric integrated lattice current collectors can be obtained by three-dimensional transfer printing liquid metal on the magnetic lattice matrix fabricated via selective laser sintering (SLS) additive manufacturing. The current collectors are endowed with the properties of mechanical-to-electric conversion and resistance thermal response, thus possessing the functionalities of strain sensing and circuit breaking at high temperature. There exist two key scientific issues to be addressed, including the influence law of SLS material and process on the interface properties between the magnetic lattice matrix and the liquid metal, and the dependence of mechanical-to-electric conversion and resistance thermal response properties on the material and structure of the current collector. Hence, a systematic investigation on the material/structure design method, fabrication process, interface properties, mechanical-to-electric conversion and resistance thermal response properties of the current collectors is conducted. Through this project, innovative achievements can be expected in the interface bonding mechanism of the SLS-printed magnetic lattice matrix and the liquid metal, and the synergistic regulation method of the mechanical-to-electric conversion and resistance thermal response properties. Consequently, the project can lay a theoretical foundation for optimizing the properties of the magnetoelectric integrated lattice current collectors and realizing the preventable and controllable safety of lithium-ion batteries, which has important scientific significance.