Review on areal capacities and long-term cycling performances of lithium sulfur battery at high sulfur loading

Abstract

Lithium-sulfur batteries (LSBs) show promise as commercial batteries for electric vehicles (EV), portable devices and grid storage due to its low cost and high theoretical energy density. For EV applications, the areal capacity of LSBs needs to reach ~6 mAh.cm -2 to compete with the state-of-the-art LIBs. However, currently the practical application of LSBs is a great challenge due to low sulfur loading, self-discharge and low sulfur utilization. As such, different strategies have been investigated to improve the feasibility of LSBs at high sulfur loading. Such approaches are critical, but few articles have focused on the areal capacity at high sulfur loading and long term cycling performance of LSBs. This review highlights the recent progress of LSBs at high sulfur loading to achieve feasible areal capacity and long-term cycling performance. Particular attention has been placed on the cathode and separators modifications, with a discussion around anode and electrolyte modifications to improve the LSB performance.

Separator coatings as efficient physical and chemical hosts of polysulfides for high-sulfur-loaded rechargeable lithium–sulfur batteries

“…The LSB is ultimately aimed to reach the theoretical energy density (2600 Wh kg −1 ). In the literature, no extensive energy density calculations are reported owing to the lack of valuable parameters such as the coating thickness, sulfur loading, and electrolyte/sulfur ratio [30,53,54] . In this study, the energy densities of all LSBs were calculated ( Fig.…”

“…A minimum areal capacity of 6 mAh cm −2 is needed so that the LSBs can compete with the state-of-the-art LIBs. To achieve this value, a minimum sulfur loading of 6 mg cm −2 with a practical specific capacity of 10 0 0 mAh g −1 is required [29,30] . However, at such high sulfur loadings, the shuttle effect is even stronger.…”

Electrode Design for Lithium–Sulfur Batteries: Problems and Solutions

“…[ 58 ] Though high reactivity and large capacity, pure sulfur cannot be directly used as the cathodes because of severe shuttle effect of soluble high‐level lithium polysulfides and poor electrical conductivity. [ 59,60 ] In view of the above, sulfur must be combined with conductive hosts such as carbon matrix, which is always the first choice because of its light weight, high electrical conductivity, and large active sulfur storage sites. [ 61 ] With great progresses on the controllable synthesis strategies, in recent years, various synthetic methods have been developed to prepare sulfur‐based cathode materials by infiltration or encapsulation of sulfur into conductive hosts including melt‐diffusion method, ball milling infiltration method, supercritical fluid infiltration method, vacuum infiltration method, dissolution–crystallization infiltration method, chemical deposition infiltration method, and electrodeposition infiltration method.…”

One‐dimensional and two‐dimensional synergized nanostructures for high‐performing energy storage and conversion

“…Advanced nanostructured design for anode materials can significantly facilitate the ion/electron transport, thus enhancing the properties of battery systems. Besides, LSBs are considered as one of the most promising candidates that could satisfy this emerging market owing to the high theoretical specific energy density and natural abundance of sulfur . However, LSBs have yet to be commercialized due to several technical obstacles, for example, the insulating feature of the end products (S and Li 2 S), lithium polysulfide (LiPS) dissolution and shuttling, and the uncontrolled precipitation of Li 2 S from the dissolved LiPS, resulting in low Coulombic efficiency, low cycling capacity, and increased internal resistance .…”