The sodium‐ion capacitor (NIC) represents an important research approach to bridge the gap between batteries and capacitors, but is still limited by inferior energy behavior at high power, low volumetric performance, low electrode mass loading, and safety issues with conventional liquid electrolyte. Herein, a high‐performing, kinetically superior, and safer quasi‐solid‐state NIC utilizing the fast sodium storage in TiO₂ and rapid ion adsorption on a biomass‐derived porous carbon with a sodium‐ion conducting P(VDF‐HFP) gel polymer electrolyte is presented. Owing to high mass loading, low graphene content in TiO₂, and by overcoming the diffusion‐limited sodium storage by surface limited storage enable the NIC to deliver an impressive volumetric energy of ≈89 Wh L⁻¹ (94 Wh kg⁻¹) based on total mass in both electrodes. Also, a remarkable power of ≈9.4 kW L⁻¹ (10 kW kg⁻¹) while retaining an energy of ≈28.7 Wh L⁻¹ (30.6 Wh kg⁻¹) is attained. Furthermore, the NIC shows a long‐term stability both at room temperature and high temperature (50 °C), outperforming conventional NICs. This research opens new opportunities for applications of high‐performing and safer NICs in next‐generation storage devices requiring high energy at high power with high safety.

中文翻译：

---

高质量负载条件下的高容量准固态钠离子电容器

钠离子电容器（NIC）是弥合电池与电容器之间差距的重要研究方法，但仍受高功率，低体积性能，低电极质量负载以及常规液体电解质安全问题下的不良能量行为所限制。在此，通过使用钠离子传导性P（VDF-HFP）凝胶，利用TiO ₂中的快速钠存储和在生物质衍生的多孔碳上的快速离子吸附，实现了一种高性能，动力学上优越且更安全的准固态NIC。提出了聚合物电解质。由于高的质量负载，TiO _2中的石墨烯含量低，并且通过克服了表面受限的储存限制了扩散限制的钠储存，使NIC能够提供令人印象深刻的≈89Wh L ^-1的体积能（94 Wh kg ^-1）基于两个电极的总质量。另外，获得了≈9.4kW L ^-1（10 kW kg ^-1）的显着功率，同时保持了≈28.7Wh L ^-1（30.6 Wh kg ^-1）的能量。此外，NIC在室温和高温（50°C）下均显示出长期稳定性，优于传统NIC。这项研究为高性能，更安全的NIC在需要高能量，高功率，高安全性的下一代存储设备中的应用提供了新的机遇。