Exploring the Low Voltage Behavior of V₂O₅Aerogel as Intercalation Host for Sodium Ion Battery

Abstract

Boosted by costs benefits, the development of room temperature Na-ion batteries is strongly desired for stationary applications. In this study we explore the possible use of V 2 O 5 aerogel as anode material for sodium ion batteries. The aerogel is able to reversibly insert more than 3 Eq. of sodium in the voltage range 0.1 V-4 V vs. Na/Na + demonstrating to possess additional capacity when cycled to lower voltage. The anode delivers about 200 mAh g −1 in the voltage range 0.01 V-1.5 V vs. Na/Na + . The preliminary characterization of a full Na-ion cell made coupling the V 2 O 5 aerogel anode with carbon-coated Na 3 V 2 (PO 4 In the past years lithium ion batteries (LIBs) have strongly evolved, conquering the market of portable electronic devices and penetrating that of electro-mobility. However, issues related to lithium availability and costs of other materials used in LIBs are rising up. Therefore, special efforts are presently dedicated to the development of alternative battery chemistries based on different shuttling cations like Mg 2+ , 1,2 Al 3+3,4 and Na + . 5,6 In this context, sodium ion batteries (SIBs) are considered as a suitable alternative to the more expensive LIB technology in stationary energy storage applications because their production does not require any technological development aside from the development of appropriate electrodes' materials. In comparison with Li + , the Na + cation is heavier (23 g mol −1 vs 6.94 g mol −1 ) and larger (0.98 Å vs 0.69 Å) leading to lower gravimetric energy and, possibly, slower kinetics. On the other hand, sodium is widely available, therefore, its cost is noticeably low, and worldwide distributed. Moreover, the absence of known Na-Al electrochemically formed alloys permits the use of aluminum current collectors at the anode side, further reducing the cost of the final battery.Presently, the research stream in SIBs' development concerns with the identification of suitable electrode materials taking advantage of the mature background available in lithium ion systems. Several cathode materials are currently investigated, especially those based on layered oxides and polyanionic compounds.6-10 The latter exhibit the advantage of being thermally more stable, 11 thus, enabling safer energy storage.Vanadium-based compounds are of particular interest due to the different oxidation states accessible realizing multi-electrons redox reactions. Indeed, Na 3 V 2 (PO 4 ) 3 is able to reversibly release two equivalents of Na + ions (corresponding to a theoretical capacity of 118 mAh g −1 ), making use of the V 3+ /V 4+ redox couple at around 3.3 V. Additionally, the same material is also investigated as negative electrode as, at 1.5 V, one additional equivalent of Na + is reversibly hosted into the structure while V 3+ is partly reduced to V 2+ . 12 The main drawback of this material is represented by the rather low electronic conductivity, which, however, can be by-passed with the use of nano-sized particles, as well as their carbon-coating. 13Among the layered oxid...

Bilayered Nanostructured V2O5·nH2O for Metal Batteries

“…[141][142][143] The rate capabilities are satisfactory, [111,139,144] but the long term cycling ability has been not yet assessed as generally not more than 100 cycles are reported and the cyclability is very much linked with the sample morphology and electrode preparation. [148] However, the possible use of this material as anode for Na-ion batteries is hindered by the need of an effective preliminary sodiation treatment to account for the large irreversible capacity loss during the first cycle. Tapavcevic et al [60] reported the reversible expansion of interlayer distance and increase of the bond lengths within the bilayers upon Na + (de-)insertion process in agreement with the findings of Su.…”

Na‐Ion Batteries for Large Scale Applications: A Review on Anode Materials and Solid Electrolyte Interphase Formation

“…A VO 2 ·1.65H 2 O/graphene composite was shown to deliver a reversible capacity of ≈210 mA h g −1 between 2.5-0.05 V versus Na +/ Na at 10 mA g −1 and after 20 cycles, although with rather low coulombic efficiency (≈67% after 20 cycles). [149] NaZr 2 (PO 4 ) 3 also crystallizes in the NASICON structure and can accommodate extra Na ions, delivering a capacity of 150 mA h g −1 at 20 mA g −1 between 2.5 and 0.01 V. It is proposed that the reaction occurs through the reduction of Zr +4 to Zr +2 , as concluded from XPS data, [150] although Zr +2 is quite rare and XPS peak assignment would be compatible with a reduction to Zr +3 . [148] V 2 O 5 was shown to deliver ≈250 mA h g −1 at C/2 in the voltage range of 2-0.01 V when prepared as an aerogel.…”

Readiness Level of Sodium‐Ion Battery Technology: A Materials Review

“…[273] The reported battery showed an operation voltage of 1.8 V and good rate capabilities with 70% of the original capacity retained at 11 C. Moreover, Yang and co-workers built a double-wall Sb@TiO 2−x structure [274] by the calcination of Sb 2 S 3 @TiO 2 nanorods, in a Ar/H 2 atmosphere, produced by the hydrolysis of tetrabutyl titanate on Sb 2 S 3 nanorods. [276] When evaluated as Na 3 V 2 (PO 4 ) 3 //V 2 O 5 , the full-cell displays the capacities of 113 and 60 mAh g −1 based on the anode and cathode materials, respectively. In this compound the excellent electrochemical stability of TiO 2−x is combined with the high theoretical capacity of Sb as an alloying material.…”