Abstract
Taken advantage of a high theoretical energy density of 2567 Wh kg-1, lithium sulfur
batteries (LSBs) have been considered promising candidates for next-generation
energy storage systems. Tremendous efforts have been devoted to improving the
battery performance by preparing smart nanostructures. However, detailed reaction
mechanisms and the principles of tailoring reaction paths remain unclear. In-situ
transmission electron microscopy (TEM) is a powerful technique to probe the
dynamic processes of electrochemical reactions at a high spatial resolution and in
real-time. Through in-situ TEM study with a solid cell, we revealed the correlation
between sulfur volume expansion and the porosity of carbon nanofibers. Further, by
developing an in-situ TEM equiped with a graphene-based liquid cell (GLC), where
liquid electrolyte and TiN-C/S nanoparticles are encapsulated between two graphene
sheets, we disclosed the nucleation and growth dynamics of solid Li2S from soluble
polysulfides. Very recently, using operando optical microscopy, we found liquid
sulfur droplets formation during charging at room temperature, which is much lower
than the melting point of sulfur. The liquid sulfur indicates superior kinetic features
from its flowing and reshaping natures. More interestingly, the preservation of liquid
sulfur is strongly linked to the substrate chemistry, where solid sulfur forms from the
edge of 2D materials. It is believed that in-situ microscopic investigation of sulfur
cathodes would not only shed new light on understanding of reaction mechanisms but
also provide fundamental guidelines to design better LSBs.
batteries (LSBs) have been considered promising candidates for next-generation
energy storage systems. Tremendous efforts have been devoted to improving the
battery performance by preparing smart nanostructures. However, detailed reaction
mechanisms and the principles of tailoring reaction paths remain unclear. In-situ
transmission electron microscopy (TEM) is a powerful technique to probe the
dynamic processes of electrochemical reactions at a high spatial resolution and in
real-time. Through in-situ TEM study with a solid cell, we revealed the correlation
between sulfur volume expansion and the porosity of carbon nanofibers. Further, by
developing an in-situ TEM equiped with a graphene-based liquid cell (GLC), where
liquid electrolyte and TiN-C/S nanoparticles are encapsulated between two graphene
sheets, we disclosed the nucleation and growth dynamics of solid Li2S from soluble
polysulfides. Very recently, using operando optical microscopy, we found liquid
sulfur droplets formation during charging at room temperature, which is much lower
than the melting point of sulfur. The liquid sulfur indicates superior kinetic features
from its flowing and reshaping natures. More interestingly, the preservation of liquid
sulfur is strongly linked to the substrate chemistry, where solid sulfur forms from the
edge of 2D materials. It is believed that in-situ microscopic investigation of sulfur
cathodes would not only shed new light on understanding of reaction mechanisms but
also provide fundamental guidelines to design better LSBs.
| Original language | Chinese (Simplified) |
|---|---|
| Number of pages | 1 |
| Publication status | Published - 29 Apr 2023 |
| Event | The 7th national lithium sulfur battery conference - Wuhan, Wuhan, China Duration: 28 Apr 2023 → 30 Apr 2023 http://7thlsb.hoohui.cn/ |
Congress
| Congress | The 7th national lithium sulfur battery conference |
|---|---|
| Country/Territory | China |
| City | Wuhan |
| Period | 28/04/23 → 30/04/23 |
| Internet address |