3D-Printed KVPO₄F/rGO Aerogel Electrodes as High-Performance 5V-Class Cathode for Advanced Potassium-Ion Battery

A porous KVPO₄F/reduced graphene oxide (KVPF/rGO) microgrid aerogel electrode is designed and fabricated using direct ink writing 3D printing for high-performance potassium-ion battery cathodes. This 3D-printed KVPF/rGO aerogel electrode, which integrates well-dispersed KVPO₄F microspheres in the reduced graphene oxide matrix, shows enhanced structural integrity and electrical conductivity, thereby facilitating efficient ion and electron transport. The KVPF/rGO electrode achieves a reversible discharge capacity of 99.0 mAh g^-1 at a current density of 50 mA g^-1 in the voltage range between 2.0 and 5.0 V. It retains 93.9% of its capacity after 100 cycles and delivers a discharge capacity of 72.6 mAh g^-1 at a high current density of 500 mA g^-1, demonstrating good rate capability. The role of rGO in improving charge transfer and minimizing polarization is demonstrated. The flexibility of the 3D-printed electrodes is validated by fabricating soft-pack batteries, which maintain stable performance under mechanical stress, an essential requirement for wearable electronics. The results highlight the large potential of 3D printing technology to enhance the properties and flexibility of potassium-ion batteries and pave the way for future advancements in energy storage devices.