Porous structure V2O5 nanoneedle arrays modified carbon cloth for stabilizing potassium metal anodes

The limited availability of lithium resources constrains the further development of dominant lithium-ion batteries. Potassium-ion batteries (PIBs), benefiting from the natural abundance of potassium, rapid ion transport kinetics, the high-capacity, and low-potential K metal anode, present a promising alternative. However, practical K metal anodes are plagued by dendrite growth, interfacial instability, and large volume changes. To address these issues, a potassiophilic host material (CC@V@K) was fabricated by first synthesizing V 2 O 5 nanoneedles on carbon cloth (CC@V 2 O 5 ) via in situ hydrothermal growth, followed by infiltration with molten K. This CC@V 2 O 5 host achieves complete potassium wetting within 1 s, features a porous structure to buffer volume changes of K, and offers abundant nucleation sites for uniform K deposition. Electrochemically, the symmetric cell exhibits stable cycling for 1200 h at 0.5 mA cm −2 . When paired with a K 0.5 V 2 O 5 cathode, the full cell retains 85.1% capacity after 300 cycles at 20 mA g −1 and delivers 68.5 mAh g −1 at 200 mA g −1 . This work demonstrates an effective host design strategy, advancing the development of practical PIBs.