Ultrafast Charging-Discharging of Nano-sized Na₃V₂(PO₄)₃ Embedded in Porous Carbon Matrix for Sodium Ion Batteries
Prozesse und Methoden (inkl. Screening) : Chemische
Sodium ion batteries are regarded as a promising alternative to lithium ion batteries due to the abundance and cheapness of sodium. Unfortunately, sodium-based cathodes exhibits poor electrochemical performance as their energy and power densities do not reach the values of lithium-based analogues. Therefore, the investigation of new sodium-based cathodes with good electrochemical performance is highly demanded.
We offer a new sodium-based composite nanomaterial for sodium ion battery cathodes. These carbon-coated nanosized Na3V2(PO4)3 particles embedded in a highly effective mixed conducting porous carbon matrix (denoted as (C@NVP)@pC) can be easily prepared by means of a facile soft-chemistry based preparation method with a post heat-treatment procedure (Fig. 1).
The so fabricated cathodes are highly porous and feature ultrafast performance and excellent cycling stability (Fig. 2). The charge-discharge profiles approve ultrafast charges and discharges within few seconds delivering both high energy and high power density. Moreover, it is to highlight that even after 1000 charge-discharge cycles at 100 C rate this cathode material maintains its original morphology and structure.
Furthermore, the results show that the electrochemical performance of the novel (C@NVP)@pC cathode matches or even outshines the common high-power lithium-based cathode materials (Fig.3).
Our results show that the soft-chemically prepared (C@NVP)@pC are very promising for application as cathodes in sodium ion batteries. They can be charged and discharges in 6 s with high current density of 22 A/g and delivers the specific capacity of 44 mAh/g and remains morphological and structure stable even after 1000 charge-discharge cycles.
- Usage of abundant and low priced element sodium
- Facile soft-chemistry based preparation method
- High rate charge and discharge properties
- Long cycling stability
C. Zhu, K. Song, P. A. van Aken, J. Maier, Y. Yu, "Carbon-Coated Na3V2(PO4)3 Embedded in Porous Carbon Matrix: An Ultrafast Na-Storage Cathode with the Potential of Outperforming Li Cathodes", Nano Letters 2014 14 (4), pp. 2175-2180
PCT priority appliction WO2015067316 filed November 2013, nationalized in EP and US.
EP3066708B1 granted, nationalized in DE, FR, GB.
- Ref.-Nr.: 1201-4746-LC (1,0 MiB)
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