Durable Integrated K-Metal Anode with Enhanced Mass Transport through Potassiphilic Porous Interconnected Mediator

K-metal batteries have become one of the promising candidates for the large-scale energy storage owing to the virtually inexhaustible and widely potassium resources. The uneven K+ deposition and dendrite growth on the anode causes the batteries prematurely failure to limit the further application. An integrated K-metal anode is constructed by cold-rolling K metal with a potassiphilic porous interconnected mediator. Based on the experimental results and theoretical calculations, it demonstrates that the potassiphilic porous interconnected mediator boosts the mass transportation of K-metal anode by the K affinity enhancement, which decreases the concentration polarization and makes a dendrite-free K-metal anode interface. The interconnected porous structure mitigates the internal stress generated during repetitive deposition/stripping, enabling minimized the generation of electrode collapse. As a result, a durable K-metal anode with excellent cycling ability of exceed 1, 000 h at 1 mA cm(-2)/1 mAh cm(-2) and lower polarization voltage in carbonate electrolyte is obtained. This proposed integrated anode with fast K+ kinetics fabricated by a repeated cold rolling and folding process provides a new avenue for constructing a high-performance dendrites-free anode for K-metal batteries.

Automated summary

K-metal batteries, using potassium as the primary resource, are promising candidates for large-scale energy storage. However, uneven potassium deposition and dendrite growth on the anode limit their application. By constructing an integrated anode with cold-rolled potassium metal and a potassium-affine porous interconnected mediator, the transportation of potassium ions is enhanced, leading to a dendrite-free and durable anode with excellent cycling ability.