Architecture of Semiconductive Macroporous Polymer Scaffold to Realize Ultra‐Fast Charging in Lithium Metal Batteries

Lithium metal batteries (LMBs) are considered ideal next‐generation energy storage systems capable of doubling the energy density of present lithium‐ion batteries. However, their practical application remains challenging at high‐speed charge/discharge rates due to the uncontrollable growth of Li dendrites and the unrestricted volume expansion. Herein, a rationally engineered multifunctional macroporous scaffold inserted into a lithium metal anode is developed to realize ultra‐fast charging while minimizing volume expansion in LMBs. The architecture integrates a polypyrrole (PPy) coating onto an insulating PVDF framework except for the top, effectively suppressing surface Li deposition and mitigating dendrite formation during fast‐charging operation. By introducing a conductivity contrast between the semiconductive PPy and Cu current collector, electron transport is regulated to induce bottom‐up Li deposition. Furthermore, the abundant pyrrolic N sites in the PPy facilitate uniform Li nucleation and enable the formation of a N‐rich SEI layer with high ionic conductivity, enhancing interfacial stability and improving Li plating/stripping kinetics. As a result, at a high‐rate LMB test of 5 C corresponding to 12 min dis/charging, the functionally designed PPy‐coated porous PVDF scaffold demonstrates 94.7% capacity retention over 200 cycles under practical conditions of 1.25 mAh cm −2 loading LFP and 3.2 NP ratio.