High Active Material Utilization Research Articles

3D-printed Bio-inspired porous electrode by bidirectional enhancement strategy with high mass loading and enhanced energy density for supercapacitors

The effective strategy for increasing areal capacity involves the use of 3D printed thick-electrode with high mass loading. However, thick-electrode still encounters challenges such as incomplete electrolyte penetration and slow ion transport. Here, we successfully prepared lignocellulosic nanofibrils (LCNFs) from abundant bamboo biomass and developed functional ink composed of LCNFs/ carbon nanotubes (CNTs) / polyaniline (PANI) / polyvinyl alcohol (PVA) for printing. An innovative 3D printing bidirectional enhancement strategy was proposed to increase the mass loading of active materials in the vertical direction and construct ion transport channels in the transverse direction. The biomimetic porous N-doped electrode obtained after annealing treatment exhibits a more continuous conductive network, larger surface area, higher utilization of active materials, and smoother ion transport pathways compared to thick-electrode. Therefore, the Triangles biomimetic electrode exhibits an enhanced areal/specific capacitance compared to thick-electrode, reaching 5.30F·cm−2 (184.03F·g−1) and 4.40F·cm−2 (122.22F·g−1) at 2 mA·cm−2, respectively. The symmetric device demonstrates an areal capacitance of 1.34F·cm−2 at 1 mA·cm−2 and achieves an energy density of 0.186 mWh·cm−2 at a power density of 0.49 mW·cm−2. The work provides valuable insights into the design of electrode structures for high-performance supercapacitors.

Free-Standing Poly(vinyl benzoquinone)/Reduced Graphene Oxide Composite Films as a Cathode for Lithium-Ion Batteries.

Quinones with a rapid reduction-oxidation rate are promising high-capacity cathodes for lithium-ion batteries. However, the high solubility of quinone molecules in polar organic electrolytes results in low cycle stability, while their low electric conductivity causes low utilization of electrode materials. In this article, a new p-benzoquinone derivative, poly(vinyl benzoquinone) (PVBQ), is designed and synthesized, and a solution-based method of preparing free-standing PVBQ/reduced graphene oxide (RGO) composite films is developed. PVBQ has a high theoretical specific capacity (400 mA h g-1) because of its low dead moiety mass. In the produced composite films, PVBQ nanoparticles are uniformly dispersed on RGO sheets, which endows the composite films with high electric conductivity and inhibits the dissolution of PVBQ through strong adsorption. As a result, the composite films show a high active material utilization, high practical specific capacity, and excellent cycling stability. PVBQ in the composite membrane containing 60.2 wt % RGO deliver 244 mA h g-1 capacity after 200 charge-discharge cycles at a current density of 300 mA g-1. At a current density of 1500 mA g-1, the reversible specific capacity is still 170 mA h g-1. This work provides a high-performance cathode material for lithium-ion batteries, and the molecular structure and electrode structure design ideas are also instructive for developing other organic electrode materials.

A solid-state electrolyte for electrochemical lithium-sulfur cells.

Post-lithium-ion batteries are designed to achieve high energy density and high safety by modifying their active material and cell configuration. In terms of the active material, lithium-sulfur batteries have the highest charge-storage capacity and high active-material utilization because of the use of a conversion-type sulfur cathode, which involves conversion between solid-state sulfur, liquid-state polysulfides, and solid-state sulfides. In terms of the configuration, solid-state batteries ensure high safety by using a solid-state electrolyte in between the two electrodes. Herein, we use a lithium lanthanum titanate (LLTO) solid-state electrolyte in the lithium-sulfur cell with a polysulfide catholyte electrode. The LLTO, which replaces the conventional liquid electrolyte, is a solid-state electrolyte that offers smooth lithium-ion diffusion and prevents the loss of polysulfides, while the highly active polysulfide electrode, which replaces the solid-state sulfur cathode, improves the reaction kinetics and the active-material utilization. The material and electrochemical analyses confirm the stabilized electrodes exhibit long-lasting lithium stripping/plating stability and limited polysulfide diffusion. Moreover, the morphologically and electrochemically smooth interface between the solid-state electrolyte and catholyte enables fast charge transfer in the cell, which demonstrates a high charge-storage capacity of 1429 mA h g-1, high rate performance, and high electrochemical efficiency.

Nafion-Based Quasi-Solid-State Polymer Electrolyte for Lithium-Sulfur Batteries

Lithium-sulfur batteries are considered a strong contender for next-generation high-energy battery systems given their high gravimetric energy density. However, this battery chemistry is still facing challenges such as the polysulfide shuttle effect caused by the high solubility of long-chain lithium polysulfides (Li2Sn) resulting in active material loss and compromised cycle life. Solid-state polymer electrolytes (SPEs) represent a promising pathway to address this issue by preventing the formation and transport of these undesirable polysulfide intermediates.1,2 Moreover, the application of flexible polymer electrolytes promotes safe high energy batteries for smart textiles.In this study, single lithium-ion conducting solid polymer electrolytes (SLIC-SPEs) based on lithiated Nafion membrane have been investigated, utilizing the chemical and thermal stability of this kind of ionomers. Among others, a mixture of ethylene carbonate (EC) and propylene carbonate (PC) was tested as organic aprotic swelling solvent offering advantageous characteristics such as great chemical stability and high ion mobility while avoiding phase separation issues and undesired leaching.Sulfur-infiltrated ultramicroporous carbon composite cathodes were utilized in combination with the investigated SLIC-SPEs, facilitating a quasi-solid-state lithium-sulfur full cell with carbonate-solvent compatibility and high active material utilization.3 Electrochemical performance of the full cell was investigated elaborately and compared with a reference system using solely the liquid EC:PC solvent. While rapid capacity fading can be observed for the liquid electrolyte cell, an enduring high capacity is found in the lithiated-Nafion system. For better understanding of these effects, cycling analysis was accompanied by implementing impedance spectroscopy upon galvanostatic cycling. The electrochemical characterization indicates the formation of a stable film and high degree of reversibility during cycling of the lithiated-Nafion cell whereas an increased film resistance due to sulfur cross-over and electrolyte decomposition was observed within the liquid electrolyte system.(1) Z. Li, W. Lu, N. Zhang, Q. Pan, Y. Chen, G. Xu, D. Zeng, Y. Zhang, W. Cai, M. Yang, J. Mater. Chem. A 2018, 6 (29), 14330-14338.(2) X. Hao, H. Wenren, X. Wang, X. Xia, J. Tu, J. Colloid Interface sci. 2020, 558, 145-154,(3) M. Nojabaee, B. Sievert, M. Schwan, J. Schettler, F. Warth, N. Wagner, B. Milow, K. A. Friedrich, J. Mater. Chem. A 2021, 9 (10), 6508-6519,

Effect of Particle Size Ratio on Microstructure and Active Material Utilization in Argyrodyte All-Solid-State Composite Cathodes

Among next-generation batteries, all-solid-state batteries (ASSB) promise increased energy densities, fast charging properties, and higher safety compared to traditional liquid-based systems. To achieve the demanded high energy densities high mass loadings of the composite cathodes are necessary. These consist of active material (AM), solid electrolyte (SE), and conductive additive as well as binder. Volume changes of intercalation AM and insufficient ionic percolation at low SE contents lead to an increased interfacial resistance and capacity loss. In order to promote cathode AM utilization the particle size ratio of the AM and the SE within the composite cathode needs to be optimized.Theoretical calculations have shown that for high AM utilization at high AM loadings particle size ratio is a crucial parameter [1, 2]. Experimentally, the influence of particle size ratio has so far only been studied at laboratory scale. However, scalable process routes have not considered this important aspect. In this work, we present a solvent-based process route for the preparation of sulfide-based solid-state composite cathodes with NCM622 as AM, starting from the adjustment of the particle size of a commercially available Li6PS5Cl SE by planetary ball mill. Further process steps include the dispersion of SE with AM and conductive additive and doctor blade coating of cathode films. We analyzed the composite cathodes with regard to their internal resistance as well as their microstructure and conducted electrochemical tests in lab-scale test cells. Optimization of the particle size ratio results in an increase of AM utilization by a factor of 5 as well as an enhanced AM-SE-particle contact area and lower porosity.

Surface Engineering in Covalent Organic Polymers for High-Performance Li-S Batteries.

Lithium-sulfur (Li-S) batteries are promising energy storage technology due to their tempting high theoretical capacity and energy density. Nevertheless, the wastage of active materials that originates from the shuttling effect of polysulfides still hinders advancement of Li-S batteries. The effective design of cathode materials is extremely pivotal to solve this thorny problem. Herein, Surface engineering in covalent organic polymers (COPs) has been performed to investigate the influence of pore wall polarity on the performance of COP-based cathodes used for Li-S batteries. With the assistance of experimental investigation and theoretical calculations, performance improvement by increasing pore surface polarity and a synergy effect of the polarized functionalities, along with nano-confinement effect of the COPs, are disclosed, to which the improved performance of Li-S batteries including outstanding Coulombic efficiency (99.0%) and extremely low capacity decay (0.08% over 425 cycles at 1.0 C) is attributed. This work not only enlightens the designable synthesis and applications of covalent polymers as polar sulfur hosts with high utilization of active materials, but also provides a feasible guide for the design of effective cathode materials for future advanced Li-S batteries.

In-situ CNT-loaded organic cathodes for sulfide all-solid-state Li metal batteries

Organic cathodes show promising advantages of extensive resources, high theoretical specific capacity, and mild synthesis conditions, etc., but suffer from low density, poor electronic conductivity, and high solubility in liquid electrolytes. Herein, an in-situ coating method is developed to overcome the above issues by realizing high-performance sulfide all-solid-state batteries with organic Li4C8H2O6 cathode. Li4C8H2O6 composite cathodes with carbon nanotubes (CNTs) and vapor grown carbon fiber (VGCF) were systematically studied to reveal that CNTs accelerate the electrochemical decomposition of sulfide electrolyte, despite the effectively improved electronic conductivity, rate capability and active material utilization. Therefore, in-situ coating of Li4C8H2O6 onto CNTs (Li4C8H2O6@CNT) is developed to further improve the contact between Li4C8H2O6 and CNTs, but to reduce the contact of CNTs with sulfide solid electrolyte and its decomposition. As a result, the Li4C8H2O6@CNT electrode demonstrates a high capacity of 200.3 mAh/g, and a high active material utilization rate (83.4% at 0.1C). It also exhibits a specific capacity of 85.9 mAh/g at a high cathode loading of 40 wt% and a high rate of 1C.

High-performance cathode promoted by reduced graphene oxide nanofibers with well-defined interconnected meso-/micro pores for rechargeable Li-Se batteries

Highly conductive nanostructures comprising one-dimensional (1D) reduced graphene oxide (rGO) nanofibers (NFs) and bimodal pores i.e., meso-/micropores, as efficient cathode hosts (Bi-P-rGO) for Li–Se batteries were prepared. The highly conductive rGO matrix acts as a self-supporting skeleton to enhance the structural integrity of the nanostructure besides providing numerous conducting pathways for rapid charge transfer. Moreover, highly interconnected chain-like mesopores guarantee efficient electrolyte percolation, whereas the micropores offer highly active material impregnation. Correspondingly, Bi-P-rGO@Se as a high-performance cathode was visualized, which demonstrated an overall enhanced electrochemical performance such as excellent rate capability (up to 20.0C) and overwhelming long-term cycling stability (73% capacity retention at the end of 800cycles with an average capacity decay rate of just 0.03% per cycle at 0.5C rate). The exceptional electrochemical performance of the Bi-P-rGO@Se cathode can be attributed to its highly porous structure, which promises efficient electrolyte infiltration and diffusion of charged species, high active material utilization within micropores, availability of conductive pathways for fast charge transfer, and high structural integrity. Therefore, we anticipate that the structural and electrochemical results presented in this work will provide significant insights into the synthesis of high-performance porous and conductive nanostructures for a wide range of applications.

Porous TiO2-x/C Nanofibers with Axially Aligned Tunnel Pores as Effective Sulfur Hosts for Stabilized Lithium-Sulfur Batteries.

Hierarchically porous TiO2-x/C nanofibers (NFs) with axially aligned cylindrical tunnel pore channels were synthesized as a sulfur (S) host for lithium-sulfur batteries (LSBs) by a microemulsion electrospinning method. We explored a synergistic chemical trapping reinforced by coordinatively unsaturated Ti3+ nuclei with oxygen deficiency (or more broadly via polar O-Ti-O units) in combination with physical trapping in both narrow pores (<5 nm) and larger ordered pore tunnels (20-100 nm) separated by thin walls to allow for a large volume of active material and rapid diffusion within the channels while effectively blocking out the diffusion of soluble lithium polysulfides. Due to this unique architecture and enhanced conductivity, the prepared materials enabled a high S loading (∼72 wt %) and significantly reduced the shuttle effect. Hence, the composite TiO2-x/C@S cathodes exhibited a high utilization of active materials, excellent rate performance, and promising cycling stability (retention of up to ∼1010 mAh g-1 after 150 cycles for the aerial capacity of 1.5 mAh cm-2, with very stable performance even for the high S loading of 2.5 mg cm-2). By designing control nanomaterials that lack either the pore tunnels or the desired chemical compositions, we elucidated the importance of the synergistic effect of both factors. This work demonstrates a successful exploration of oxide NFs with tunnel pores via a simple single-needle microemulsion electrospinning method, which should pave the way for similar nanomaterials engineering with other chemistries for improved LSB performance.

Revealing the accelerated reaction kinetic of Ni-rich cathodes by activated carbons for high performance lithium-ion batteries

Activated carbons (AC) play a key role in enabling the reaction kinetic of cathodes in lithium ion batteries (LIBs). However, the charge transfer dynamics and reaction kinetics mechanism of AC composited cathodes along their thickness direction are still poorly understood. Herein, we systematically compare the internal reactive process evolutions of AC modified LiNi0.6Co0.2Mn0.2O2 (NCM622) cathodes and pristine NCM622 cathodes at high C-rates. The charge transfer dynamic is revealed by the time of flight secondary ion mass spectrometry and X-ray photoelectron spectra analyzes. The addition of AC endows the NCM622 cathode regions close to the current collector possess higher lithium ion concentrations, meanwhile more Ni2+ can be converted into Ni3+. The results of COMSOL Multiphysics simulations based on the porous electrode theory is analyzed to explore reaction kinetics mechanism. AC in NCM622 cathodes homogenizes the reaction distributions, contributing to the boosted reaction kinetic, eventually, resulting in the high utilization of active materials. These findings provide a direct way to reduce solid-state diffusion resistances and accelerate reaction kinetics of electrodes, which is critical for developing batteries with long cycle stability and rate performance at high rates.

A high-performance electrode based on low cobalt content Co0.12Ni1.88S2 growing on honeycomb-like NiCo(HPO4)2·3H2O for hybrid supercapacitors

It is desirable to design highly electrochemically active materials for practical hybrid capacitors to fulfill the demand of rapid development of portable and wearable electronics. In this work, ternary Co0.12Ni1.88S2 with low cobalt content is electrodeposited on honeycomb-like NiCo(HPO4)2·3H2O modified carbon cloth (CC@Ni–Co–P@Co0.12Ni1.88S2). The as-prepared CC@Ni–Co–P@Co0.12Ni1.88S2 can avoid the introduction of inactive components. Besides, the honeycomb-like Ni–Co–P modifier provides many active sites for Co0.12Ni1.88S2 deposition and improves its utilization efficiency. Significantly, in the three-electrode system, the CC@Ni–Co–P@Co0.12Ni1.88S2 shows specific capacitance of 1.06 F/cm2, which is three times higher than that of CC@Co0.12Ni1.88S2 without Ni–Co–P modification. Surprisingly, the hybrid supercapacitors based on CC@Ni–Co–P@Co0.12Ni1.88S2 cathode and active carbon anode also delivers excellent long-term cycle stability with capacitance retention of 94.8% after 10,000 cycles. This rational structure design provides a choice for achieving high utilization of high-quality active materials.

Realizing High Utilization of High-Mass-Loading Sulfur Cathode via Electrode Nanopore Regulation.

One main challenge of realizing high-energy-density lithium-sulfur batteries is low active materials utilization, excessive use of inert components, high electrolyte intake, and mechanical instability of high-mass-loading sulfur cathodes. Herein, chunky sulfur/graphene particle electrodes were designed, where active sulfur was confined in vertically aligned nanochannels (width ∼12 nm) of chunky graphene-based particles (∼70 μm) with N, O-containing groups. The short charge transport distance and low tortuosity enabled high utilization of active materials for high-mass-loading chunky sulfur/graphene particle electrodes. The intermediate polysulfide trapping effect by capillary effect and heteroatoms-containing groups, and a mechanically robust graphene framework, helped to realize stable electrode cycling. The as-designed electrode showed high areal capacity (10.9 mAh cm-2) and high sulfur utilization (72.4%) under the rigorous conditions of low electrolyte/active material ratio (∼2.5 μL mg-1) and high sulfur loading (9.0 mg cm-2), realizing high energy densities (520 Wh kg-1, 1635 Wh L-1).

Nanostructured Poly(hydroquinonyl-benzoquinonyl sulfide)/Multiwalled Carbon Nanotube Composite Cathodes: Improved Synthesis and Performance for Rechargeable Li and Mg Organic Batteries

Cost-effective, simple, and easily reproducible synthesis methods of polymers are of profound significance when it comes to extracting high battery performance metrics from polymeric redox-active materials. This work reports a procedure for the solvothermal synthesis of a poly(hydroquinonyl-benzoquinonyl sulfide) (PHBQS) polymer and the development of its nanostructured composites with multiwalled carbon nanotubes (MWCNTs). Polymers are tested as high-performance cathode materials for Li+ and Mg2+ batteries. In configurations, compared to neat PHBQS, the PHBQS@5%MWCNT cathode exhibits superior electrochemical performance with high active material utilization owing to improved ion/electron transport pathways. Galvanostatic characterization of the PHBQS@5%MWCNT cathode in lithium batteries exhibited peak capacity up to 358 mAh g–1 at a current density of 50 mA g–1 (C/8) and excellent rate performance with a discharge capacity of 236 mAh g–1 maintained even at high current density of 10C. The galvanostatic characterization in Mg batteries reveals more sluggish kinetics with a stable capacity of 200 mAh g–1 at 50 mA g–1.

Bimetallic sulfide nanoneedle arrays for lithium ion storage: monocrystalline versus polycrystalline

Growing mixed metal sulfides onto conductive substrates is promising in constructing self-supported flexible electrodes. However, most mixed metal sulfides grown on conductive substrates exhibit polycrystalline properties, while single crystallites are rarely reported due to the Kirkendall effect during the anion exchange process. In this work, single-crystalline CoNi2S4 directly grown on carbon cloth is obtained via tuning the diffusion of involved species with the help of fluorine ions during the anion exchange process. The received single-crystalline CoNi2S4 exhibits better electrochemical properties than the polycrystalline counterpart, establishing its significance as an electroactive material for lithium-ion batteries. Ex-situ data indicate that the single-crystalline CoNi2S4 particles exhibit local homogeneity and higher active material utilization upon lithiation/delithiation process, accounting for the enhanced electrochemical performance. These results highlight the importance of single-crystal active materials in constructing self-supported electrodes and reveal a promising opportunity for obtaining high-performance flexible electrodes.

Disulfide Dichloride: A High Efficiency Vulcanizing Agent for Sulfurized Polyacrylonitrile

Sulfurized polyacrylonitrile (SPAN) cathodes have shown great prospects in commercial applications due to the high discharge capacity, good cycle stability, and low self-discharge rate. However, high sulfurization temperature results in loss of nitrogen atoms, which leads to imperfect SPAN structure and is not conducive to fast electron transfer. A high efficiency vulcanizing agent of S2Cl2 was used to reduce the reaction temperature in this work. We found that S2Cl2 promotes PAN cyclization, reduces the cyclization reaction temperature, and avoids the loss of nitrogen atoms and the agglomeration of SPAN primary particles in high-temperature reactions. The SPAN cathode material prepared using S2Cl2 has a more regular structure six-membered ring main chain structure and a smaller primary particle size, which is beneficial to the rapid conduction of electrons and lithium ions in the electrode material. The electrochemical test results confirmed that the SPAN cathode material prepared by S2Cl2 has higher active material utilization, better cycle stability, and better rate performance.

Bamboo Weaving Inspired Design of a Carbonaceous Electrode with Exceptionally High Volumetric Capacity.

A highly densified electrode material is desirable to achieve large volumetric capacity. However, pores acting as ion transport channels are critical for high utilization of active material. Achieving a balance between high volume density and pore utilization remains a challenge particularly for hollow materials. Herein, capillary force is employed to convert hollow fibers to a bamboo-weaving-like flexible electrode (BWFE), in which the shrinkage of hollow space results in high compactness of the electrode. The volume of the electrode can be decreased by 96% without sacrificing the gravimetric capacity. Importantly, the conductivity of BWFE after thermal treatment can reach up to 50,500 S/m which exceeds that for most other carbon materials. Detailed mechanical analysis reveals that, due to the strong interaction between nanoribbons, Young's modulus of the electrode increases by 105 times. After SnO2 active materials is impregnated, the BWFE/SnO2 electrode exhibits an exceptionally ultrahigh volumetric capacity of 2000 mAh/cm3.

Flexible, Electrically Conductive, Nanostructured, Asymmetric Aerogel Films for Lithium–Sulfur Batteries

Lithium-sulfur batteries are afflicted with capacity fading on account of polysulfide shuttling. A novel cost-effective electrode that can hinder the polysulfide shuttling and realize high active material utilization is highly required. Here, we demonstrate a flexible, electrically conductive, nanostructured, and asymmetric hybrid cathode by integrating a high-aspect-ratio wood nanocellulose and a low-cost commercial carbon nanotube (∼$ 0.2 g-1) into an entangled aerogel film. The vacuum filtration combined with lyophilization enables the aerogel film with quite different nanofiber/nanotube packing densities and pore structures at its two sides. The cooperative effects of the entangled building blocks and the asymmetric porous structure of the aerogel film stimulate the simultaneous increase of active sulfur loading, enhancing the electrolyte penetration, alleviating dissolution and shuttling of polysulfide ions, and promoting the fast electron transportation. The as-generated cathode exhibited a capacity fading of 0.01% per cycle over 1000 discharge/charge cycles at a 0.5 C rate (1 C = 1675 mA g-1). The average Coulombic efficiency reached ∼99.7%.

Solid State Li-Metal Battery Based on Novel Polymer Electrolyte

Conventional Li-ion batteries (LIBs) with unique advantages, exhibit a limited cycle life and significant safety problems due to the flammable organic solvent electrolytes. A solid-state battery (SSB) utilizing a solid electrolyte can potentially address the above issues. However, despite recent advancements, a truly commercially viable candidate for SSB electrolyte remains elusive. Although inorganic lithium-ion conductors are available, their practical applications have been mainly hindered by interfacial issues, since it is very challenging to construct intimate contact between the solid electrode and solid electrolyte due to their rigidity in conventional SSBs, leading to high polarization and low utilization of active materials. Storagenergy Technologies, Inc. has developed a novel polymer electrolyte that exhibits high Li+ conductivity, wide electrochemical window, and wide operational temperature. We also demonstrated a simple but effective interfacial engineering approach to improve the active material utilization via in-situ polymerization process. Complete characterization including cycling life, rate capability, thermal stability, calendar life and safety testing of coin cells and pouch cells with develop polymer electrolyte will be presented.

The vertically aligned graphene/graphite/PPy composites electrode and its PPy thickness-dependent electrochemical performance

Exceptional performance which derived from lab-scale electrodes used in electrochemical capacitors often fail to extrapolate to high mass loading conditions considering the trade-off relationship between penetration depth and charge transfer efficiency. A novel graphene/graphite/PPy(polypyrrole) composites fiber is fabricated with vertically aligned channels, offering fast diffusion pathways for the ion. By controlling the time of PPy electrodeposition, the trade-off between the PPy thickness (x) and the width of channels (y) is discussed referring to their electrochemical performance. Understanding the x-y dependent transport kinetics of the three-dimensional microstructural electrode help achieves a higher utilization of active materials. The fabricated all solid-state supercapacitor perform advanced energy density (0.117 mWh/cm2) and power density (26.7 mW/cm2). This study may also provide a guidance for the optimization of pore width and wall thickness of the three-dimensional electrode (or scaffold) design.

Minimizing Long-Chain Polysulfide Formation in Li-S Batteries by Using Localized Low Concentration Highly Fluorinated Electrolytes

Electrolytes that suppress the formation of long-chain polysulfides and limit the sulfur (S) cathode dissolution and polysulfide shuttle effect, while maintaining high active material utilization and long cycle life, have long been sought for advancing Li-S battery applications. Here we demonstrate that localized electrolytes based on fluorinated ethers with the total salt concentration of only 0.1 M show remarkable performance characteristics. By systematically reducing the fraction of sulfolane (SL) as a cosolvent with 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropylether (HFE), we reveal a dramatic change in the cell discharge behavior. The higher voltage ∼2.4 V plateau corresponding to the formation of long-chain polysulfide shrank, while the medium voltage ∼2.1 V plateau corresponding to the transformation to short-chain polysulfides almost disappeared. Additionally, a third low voltage plateau (∼1.9 V) emerges as S transform directly to a short chain polysulfides and Li2S, which have significantly lower solubilities. This plateau extended with increasing HFE and became a dominant process. When compared with the traditional dimethoxyethane/1,3-dioxolane (DME/DIOX) electrolyte solvent mixture, the reported electrolytes offer substantially higher capacity and coulombic efficiency due to decreased solubility for Li+ in the HFE, causing a shift to favoring short chain length polysulfides in the discharge reaction.