Insight into the Effects of Operation Temperature on the Electrochemical Reactions of SnO₂ as an Anode in Sodium-Ion Batteries

Abstract

The operation temperature is one of the key factors affecting the electrochemical reactions and further performances of secondary-ion batteries. In this work, the electrochemical reactions of the SnO 2 nanoparticles supported on reduced graphene oxide (SnO 2 /rGO) as an anode in sodium-ion batteries at the operating temperatures from 10 to 50 °C are systematically investigated. It is illustrated that the alloying reaction between metallic Sn and Na + is hard to take place at relatively lower temperature (10 °C), and there is dead tin accumulated at relatively high temperature (50 °C) during sodiation/desodiation, which results in the lower specific capacity of SnO 2 /rGO for sodium storage. The reason why the alloying reaction takes place hardly at low temperature is mainly attributed to the severe polarization of electrodes, but not the low diffusion coefficient of Na + within tin. The formation of dead tin at 50 °C arises from the agglomeration of larger SnO 2 nanograins in which the Sn generated during the sodiation cannot be fully oxidized during the following desodiation process forming finally the dead Sn after long-term cycling.

Emerging Chemistry for Wide-Temperature Sodium-Ion Batteries

“…176 These issues eventually lead to poor cycling stability and rate performance. At present, carbon-based materials such as reduced graphene oxide (rGO) 178,179,181,184 and multiwall carbon nanotubes (MWCNTs) 180 are commonly used as coating layers to solve these challenges. On the one hand, the carbon layer can act as an effective buffer to alleviate volume expansion.…”

“…More importantly, the electrochemical reactions of these anodes would be greatly affected by the operating temperatures. Take the SnO 2 /rGO anode 184 for example, the conversion and alloying reaction are available at different voltage regions. Normally, the alloying reaction only occurs after several cycles, whereas a low operating temperature of 10 °C allows the alloying reaction to thoroughly disappear, owing to severe polarization of electrodes brought by LTs (Figure 13d).…”

“…Copyright 2023 Wiley-VCH. Panel d is reproduced with permission from ref . Copyright 2022 American Chemical Society.…”

Comparing Cycling and Rate Response of SnO2 Macroporous Anodes in Lithium-Ion and Sodium-Ion Batteries

“…From the diminishing of the two lower voltage regions in the DCPs, a reduction in capacity from the reduction and alloying processes occurs for each increase in rate, in line with the literature. 123 The narrowing shows that each increase in rate results in much sharper reduction and alloying processes.…”