Electrochemical and thermal properties of hard carbon-type anodes for Na-ion batteries

Is single layer graphene a promising anode for sodium-ion batteries?

“…All these experiments were performed using 1M NaPF 6 (EC:DEC, 1:1, w:w) as the electrolyte solution. In general terms, the intense cathodic and anodic peaks due to the insertion and de-insertion processes of Na + ions in carbon materials [5,7,[11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] do not appear in the CVs of SLG/Cu electrodes. More specifically, the CV of cycle 1 displays a significant cathodic current that has been previously observed in the study of the interaction of Li + ions with SLG [34] and attributed to the formation of a solid electrolyte interphase (SEI) layer as a consequence of the electrolyte irreversible reduction.…”

“…3, the cells start to show good electrochemical performance in terms of cycling stability as well as coulombic efficiency (≥ 90 %, ≥ 85 % for NaClO 4 in PC electrolyte) after 20 discharge-charge cycles. However, during the initial cycles (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20), these electrochemical parameters, particularly the capacity retention, were much lower.…”

“…Therefore, efforts have been focused on the identification of other host carbon materials to achieve a successful reversible intercalation/insertion of the larger Na + anions. Thus, a variety of carbons having a certain degree of porosity, a low-ordered structure consisting of few-layers graphite nanocrystallites (graphite domains) and different morphologies, including hard and soft carbons [5,7,[11][12][13][14][15], carbon fibers and nanofibers [16][17][18][19][20], spherical carbons [21], hollow carbon nanowires [22] and nanospheres [23], reduced graphene oxide, [24] pyrolytic carbons from graphite oxide [25], as well as highly disordered carbon composites [26,27] have been investigated as anodes for SIBs. Good results as regards capacity and cycling stability were achieved with some of these carbons, the rate capability and particularly, the low coulombic efficiency during the first charge/discharge cycle due to the relatively large surface area (as compared with graphitic carbons) being the main drawbacks to overcome.…”

Expanded graphitic materials prepared from micro- and nanometric precursors as anodes for sodium-ion batteries

“…Thus, different carbon materials with diverse structures (micro-and nanostructures) and varied morphologies, usually with a certain degree of porosity and low-ordered structure consisting of few-layer graphite nanocrystallites, have been investigated for this application [12]. Among them, hard carbons are arguably the most promising candidates thus far [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34], being able to deliver reversible capacities >300 mA h g -1 at low-to-moderate current rates with remarkable stability along cycling, although some aspects need to be improved for their implementation as anodes for SIBs, such as their relatively low coulombic efficiency in the first cycle, which is related to their high surface area and porosity, or their modest rate performance. The turbostratic structure of these materials, consisting in few-layer-stacked graphite nanocrystallites with high interlayer distances (0.37-0.40 nm), together with their inherent porosity (i.e.…”

Thermal Analysis on Na Plating in Sodium Ion Battery

“…[1][2][3] The thermal safety of SIB can be a critical issue for practical use because the chemistry is very similar to LIB. Although, there are several reports on the safety of SIB, such as the effects of electrolyte, electrochemical active materials, and overcharge, [4][5][6] the effects of sodium (Na) plating on thermal safety is rarely reported as we know.…”