After a certain number of cycles of lithium batteries using traditional commercial separators, a large number of "cauliflower-like" lithium dendrites will appear on the surface of the lithium metal anode. Lithium dendrites are a common problem in lithium metal batteries. They not only cause battery short circuits, but also accelerate the aging process of the battery.
Recently, the scientific research team of the Materials Research Center of the Institute of Modern Physics, Chinese Academy of Sciences and collaborators developed aA multifunctional battery separator based on ion tracking technology - ion management membrane (IMM).
Schematic illustration of ion transport characteristics and lithium deposition behavior on the anode surface of an ion management membrane (right) and a conventional porous separator (left)
On the anode surface facing the ion management membrane (IMM),A more dense and uniform lithium deposition is achieved without obvious lithium dendrite growth.
It turns out that the pore structure of traditional porous separators (PPS) exhibits inconsistent pore diameters and pore lengths, resulting in uneven lithium ion concentration distribution under the separator pores.
This ion management membrane has vertically arranged electronegative nanopores with uniform pore sizes, showing a uniform lithium ion concentration distribution.
Simply put, it allows lithium ions to travel more smoothly and efficiently in the battery, thereby making the battery perform better, charge faster, and last longer.
Ion management membrane helps achieve dendrite growth-free lithium metal anode
The Chinese Academy of Sciences said that under certain conditions, this ion management membrane can extend the cycle life of lithium batteries to 1,200 hours. For Li/LiFePO4 batteries, this process can maintain 79.84% capacity after 1,000 cycles.
This research work provides new ideas for the design and development of multifunctional battery separators, as well as solving the safety issues of high-performance lithium metal batteries.
Paper information: https://doi.org/10.1002/aenm.202401377