Morphology Dependency of Li3V2(PO4)3/C Cathode Material Regarding to Rate Capability and Cycle Life in Lithium-ion Batteries

Self-standing NASICON-type electrodes with high mass loading for fast-cycling all-phosphate sodium-ion batteries

“…Hence, the NTP/CNFs and NVP/CNFs electrodes contained surface and bulk particles in a weight ratio of roughly 1 : 1. The morphological features of the as-prepared electrodes could effectively benet their electrochemical performance because (i) the full use of the space in the CNFs for mass loading in such a way that particles of the active material are located on the surface and in the bulk of CNT bunches results in a large specic capacity of the electrodes; (ii) the carbon phases can help to circumvent the intrinsic poor electronic conductivity of phosphate electrode materials and improve the binding between the active materials and CNFs; [34][35][36][37] (iii) the carbon layers can protect the NTP and NVP particles against erosion by the electrolyte and thus increase the cycling life of the electrodes; (iv) the small particle size of the NTP and NVP materials guarantees short diffusion pathways for Na + in the active materials, as well as relatively large specic surface areas of the electrodes (50.5 m 2 g À1 for NTP/CNFs and 49.4 m 2 g À1 for NVP/CNFs), which provides excellent kinetics for the intercalation/deintercalation of Na + and reduces polarization during cycling; [38][39][40][41][42] and (v) the high porosity of the electrodes, which was about 69% for the NTP/CNFs and NVP/CNFs electrodes as calculated from the relative and theoretical densities of the materials, could reduce the wetting issue of the electrolyte. Therefore, the as-prepared NTP/CNFs and NVP/ CNFs electrodes are expected to be capable of providing high exibility, high rate capability and stable cycling performance for SIBs in practical applications.…”

Insights into a layered hybrid solid electrolyte and its application in long lifespan high-voltage all-solid-state lithium batteries

“…According to the CV result of LHSE shown in Fig. 3d, the SPE coating signicantly improved the electrochemical stability of LATP and thus extended the voltage window of LHSE to a range of 0-4.7 V. Therefore, the electrochemical stability window of LHSE covers the phase transition potential of Li 3 V 2 (PO 4 ) 3 / LiV 2 (PO 4 ) 3 (4.11 V vs. Li/Li + ) and even the complete phase transition of Li 3 40 To gain insight into the electrochemical behavior of the Li|LHSE|Li 3 V 2 (PO 4 ) 3 /CNT all-solid-state battery, CV was performed rst in a broad voltage range of 3.0 to 5.0 V at a scan rate of 0.05 mV s À1 at 50 C (cf. Fig.…”

“…At the potential range above 4.7 V, the oxidation peak at 4.79 V (f) is assigned to the decomposition of LHSE, which is also accompanied by a strong polarization effect at higher potential. In lithium free vanadium phosphate, the V sites exhibit a fairly close average bond distance and an average vanadium valence of +4.5, 40 indicating that the mixed V 4+ and V 5+ states do not display charge ordering in this phase. Such phenomena will result in a disordered lithium reinsertion, as is evidenced by the solid solution behavior during the reduction process, which has also merged with the reduction peaks of Li 2 V 2 (PO 4 ) 3 / Li 2.5 V 2 (PO 4 ) 3 and Li 2.5 V 2 (PO 4 ) 3 / Li 3 V 2 (PO 4 ) 3 owing to the large polarization caused by the electrolyte decomposition (together denoted as region (g)).…”

Electrospun Na3V2(PO4)3/C nanofibers as self-standing cathode material for high performance sodium ion batteries

“…Unfortunately, similar to Li 3 V 2 (PO 4 ) 3 [18][19][20], NVP has relatively low electronic conductivity that limits its electrochemical performance. These problems are overcome, by applying various strategies, such as controlling the particle size [21,22], coating the Na 3 V 2 (PO 4 ) 3 with conductive materials [23,24], or doping with metal ions [25].…”