All-Liquid-Phase Reaction Mechanism Enabling Cryogenic Li–S Batteries

Abstract

The sluggish solid−solid conversion kinetics from Li 2 S 4 to Li 2 S during discharge is considered the main problem for cryogenic Li−S batteries. Herein, an all-liquidphase reaction mechanism, where all the discharging intermediates are dissolved in the functional thioether-based electrolyte, is proposed to significantly enhance the kinetics of Li−S battery chemistry at low temperatures. A fast liquidphase reaction pathway thus replaces the conventional slow solid−solid conversion route. Spectral investigations and molecular dynamics simulations jointly elucidate the greatly enhanced kinetics due to the highly decentralized state of solvated intermediates in the electrolyte. Overall, the battery brings an ultrahigh specific capacity of 1563 mAh g −1 sulfur in the cathode at −60 °C. This work provides a strategy for developing cryogenic Li−S batteries.

Challenges and advances in wide-temperature rechargeable lithium batteries

“…This mechanism successfully bypassed the slow “solid to solid” transformation route and favoured a fast liquid-phase pathway, leading to a dramatic decrease of the reaction activation energy. 126…”

PPy-constructed core–shell structures from MOFs for confining lithium polysulfides

“…[4][5][6] Different from hollow structures, the inner core can provide an additional surface to provide more active sites, which can significantly improve the efficiency of space utilization. 7,8 The hollow cavity can solve the problems of volume expansion and shrinkage of electrode materials. 9,10 As a result, the core-shell structured materials used as the cathode material in Li-S batteries have a promising prospect because of their high cycling stability.…”

Unraveling the Effect of Cation Types on Electrochromic Properties of Titanium Dioxide Nanocrystals

“…In Figure 3(c), the film in Al 3+ electrolyte decreases gradually with the increase of temperature, indicating that the speed of Al 3+ transfer from solution to the surface of W-doped TiO 2 NC film increases with the increase of temperature. Based on this, we used the Arrhenius equation to calculate the activation energy (E a ) of the electrode interface of three electrolytes/W-doped TiO 2 NCs [48,49]. E a can be obtained by fitting the slope (E a /R) of this linear equation.…”

“…E a can be obtained by fitting the slope (E a /R) of this linear equation. To facilitate comparison, we have adopted different drawing methods, which have appeared in previous reports [48,49]. After calculation, the activation energies of the film in Li + , Zn 2+ , and Al 3+ electrolytes are 2.89, 1.89, and 2.67 eV, respectively.…”