Lithium-Sulfur Batteries for EV Applications

Lithium-sulfur battery with high specific capacity by optimizing the ratio of sulfur in the electrode to sulfur dissolved in the electrolyte. This involves controlling the amount of elemental sulfur in the electrode compared to the amount that elutes into the electrolyte during charging/discharging. A target ratio of less than 15% of sulfur in the electrolyte relative to the electrode sulfur helps prevent capacity loss due to sulfur elution.

Source

Lithium-sulfur battery with improved lifetime and high energy density. The battery uses an electrolyte system containing fluorinated ether solvents, glyme solvents, and a specific lithium salt. This electrolyte enables utilizing over 80% of sulfur's theoretical capacity (1,675 mAh/g) compared to conventional catholyte systems. The high-performance electrolyte is combined with a positive electrode containing sulfur and carbon. This allows the battery to have over 400 Wh/kg or 600 Wh/L energy density without degrading the lithium anode or generating gas.

Source

Lithium-sulfur battery electrolyte suitable for low-temperature operation that improves energy density and cycle life at low temperatures. The electrolyte contains organic solvents, lithium salts, lithium nitrate additives, and an additive of 2,2,2-trifluoroethyl-3,3,3-trifluoropropyldiselenide. The diselenide additive inhibits side reactions between lithium metal and the electrolyte, promotes uniform lithium deposition, and enhances sulfur conversion kinetics through reversible sulfur-selenium exchange.

Source

A modified separator for lithium-sulfur batteries that improves performance by preventing polysulfide shuttle and enhancing sulfur utilization. The separator is coated with a composite layer made of a hollow sea urchin-shaped nickel-cobalt bimetallic organic framework (MOF) and reduced graphene oxide (RGO). The MOF adsorbs and catalyzes polysulfides, preventing their migration to the anode. The RGO provides electronic conductivity to the sulfur cathode. The MOF's porous structure and RGO's high surface area improve sulfur loading and electrolyte absorption.

Source

Cathode materials for lithium-sulfur batteries that improve performance and overcome limitations of using sulfur as the active cathode material. The cathode comprises a mixture of electroactive sulfur, like S8 or Li2S, and non-sulfur electroactive materials, like metal chalcogenides or oxides. The blended cathode has discharge voltage profiles that approximate sulfur's, allowing full sulfur conversion. The non-sulfur materials prevent sulfur agglomeration and enable high sulfur loading. This improves cycling and reduces capacity fade compared to pure sulfur cathodes.

Source

High-energy lithium-sulfur soft pack battery with improved cycling stability and capacity. The battery has a composite positive electrode with a buffer layer made of a mixture of carbon and a rare earth compound. This buffer layer is integrated with the positive electrode and current collector. The buffer layer reduces internal resistance, inhibits expansion and polysulfide shuttling in the positive electrode during charging/discharging. The negative electrode has a thin lithium layer coated with a conductive polymer to prevent dendrite growth. The high loading sulfur anode is 10mg/cm2. The battery has energy density of 500Wh/kg.

Source

Lithium-sulfur battery with improved lifetime and reduced dendrite growth by using a Li-Mg alloy negative electrode and a furan-based electrolyte. The Li-Mg alloy suppresses dendrite formation compared to bare lithium. The furan solvent helps prevent side reactions between lithium and sulfur.

Source

All-solid-state lithium-sulfur battery using a polysulfide cathode and a sulfide solid electrolyte to overcome the challenges of liquid electrolytes in lithium-sulfur batteries. The solid electrolyte prevents explosions and allows higher sulfur loading compared to liquid electrolytes. The polysulfide cathode avoids the loss of active materials during cycling compared to carbon-mixed cathodes. The solid electrolyte forms a protective layer with the cathode to reduce interface resistance and improve cycling life. The battery assembly uses a lithium anode and solid electrolyte ingot sandwiched between the cathode and separator.

Source

Lithium-sulfur battery with improved cycle life and capacity compared to conventional lithium-sulfur batteries. The improvement comes from using a protective film made of carbon nanofibers doped with vanadium nitride between the sulfur cathode and separator. The film has high electrical conductivity and polysulfide trapping ability to suppress shuttle effects. The film is prepared by electrospinning a vanadium acetylacetonate-PAN solution followed by heat treatment. The film forms a conductive network on the cathode surface to facilitate charge transfer and traps polysulfides to prevent cycling degradation.

Source

Lithium-sulfur battery with long cycle life and 100% coulombic efficiency by using a solid-phase conversion reaction mechanism instead of the dissolution-deposition reaction mechanism found in conventional lithium-sulfur batteries. The battery uses a sulfur-carbon composite anode, lithium cathode, and an electrolyte with a specific mixture of organic solvent and vinylene carbonate (VC). The VC forms a stable and dense interfacial film to isolate the active materials from the electrolyte and prevent polysulfide dissolution, enabling a solid-phase conversion reaction and avoiding the dissolution loss of active materials. This allows 100% coulombic efficiency and improved cycle stability compared to conventional lithium-sulfur batteries with carbonate electrolytes.

Source

Lithium-sulfur battery with improved cycle life by using a sulfur-modified polyacrylonitrile (S-PAN) compound as the positive electrode active material along with a specific electrolyte. The S-PAN material prevents dendrite formation, electrolyte decomposition, and shuttling of lithium polysulfides. The electrolyte contains a solvent with a heterocyclic compound containing double bonds and oxygen/sulfur atoms, plus diglyme. This synergistic electrolyte helps mitigate issues like polysulfide dissolution, electrolyte degradation, and side reactions.

Source

Lithium-sulfur battery with improved performance by using a liquid active material at the cathode, a local high-concentration electrolyte, and a diaphragm. The liquid active material forms a separate liquid-liquid interface with the local high-concentration electrolyte. During cycling, it generates lithium salts at the interface that act as ion channels and enhance ionic conductivity. This improves kinetics and reduces shuttling of polysulfides compared to using the liquid active material alone.

Source

A durable lithium-sulfur battery that has improved cycle stability and life compared to conventional lithium-sulfur batteries. The battery includes a specific separator between the positive and negative electrodes that helps prevent the "shuttle effect" where polysulfide ions migrate between electrodes and degrade performance. The separator has a functional layer made by coating a slurry of vermiculite, titanium dioxide, and carbon onto a base film. The vermiculite absorbs polysulfides during charging/discharging to reduce shuttling and improve sulfur utilization.

Source

Lithium-sulfur battery without a lithium metal anode for improved safety and cycle life compared to conventional lithium-sulfur batteries. The battery structure omits the lithium metal anode and instead uses a sulfur anode containing a lithium source, a sulfur-based positive electrode, an electrolyte, and an anode containing a lithium source. This allows replacing the lithium metal anode with a sulfur anode and lithium source in the cathode and anode to avoid dendrite growth and side reactions. The sulfur anode is made by mixing sulfur, carbon, binder, and lithium source on a current collector. The anode containing lithium source is made similarly with sulfur, carbon, binder, and lithium source.

Source

Lithium-sulfur battery with improved performance by reducing sulfur dissolution and shuttle effects. The battery uses a specially designed positive electrode pole piece that has a current collector, a positive electrode layer, and a separator layer. The positive electrode layer is made of spherical sulfur particles with a conductive agent and binder. The separator layer contains materials like acetylene black, activated carbon, carbon nanotubes, and long carbon fibers. This configuration reduces sulfur dissolution and improves cycling by trapping any dissolved sulfur in the separator.

Source

Lithium-sulfur battery with improved cycling performance and reduced sulfur shuttle effect. The battery has a lithium-sulfur chemistry with a lithium-sulfur positive electrode and an electrolyte containing a specific compound. The compound, which has formulas containing S-S, S-Se, or Se-Se bonds, is added to the electrolyte at a mass percentage E. The positive electrode porosity P is also measured. The battery has improved cycle life and capacity retention when the ratio E/P is 0.02 to 0.3, preferably 0.05 to 0.17. This is attributed to the compound preventing sulfur shuttle and the porosity allowing ion conduction.

Source

Lithium-sulfur battery with improved cycle life by using a sulfur-modified polyacrylonitrile (S-PAN) positive electrode material and a specific electrolyte containing heterocyclic solvents and diglyme. The S-PAN cathode material prevents sulfur shuttle and dendrite formation. The electrolyte solvents synergistically reduce side reactions and electrolyte decomposition compared to conventional solvents like sulfolane. The battery composition improves cycle life and capacity compared to standard lithium-sulfur batteries.

Source

Electrolyte solution for lithium-sulfur secondary batteries that improves battery life and capacity retention. The electrolyte contains vinylene carbonate at specific concentrations when used in lithium-sulfur batteries with sulfur-based cathodes. The vinylene carbonate helps prevent polysulfide dissolution during cycling that degrades battery performance. The electrolyte composition is 10-100 wt% vinylene carbonate in the solvent.

Source

Lithium-sulfur secondary battery with improved performance by optimizing the electrolyte composition for high energy density batteries with low porosity positive electrodes. The battery contains a specific volume ratio of nitrile, fluorinated ether, and disulfide solvents in the electrolyte. This reduces viscosity and increases ionic conductivity to improve initial discharge capacity and average voltage for high loading, low porosity positive electrodes.

Source

Solid-state lithium-sulfur battery with improved safety and cycling performance compared to liquid electrolyte batteries. The battery has a solid electrolyte sandwiched between a cathode containing sulfur, carbon, and a solid electrolyte, and an anode of lithium metal. The cathode also has a small amount of copper. The copper content is limited to 0.37 g/Ah discharge capacity and the charged state Cu/Li ratio is less than 0.81 to prevent excessive copper plating. This composition and intercalated solid electrolyte between the cathode and anode avoids issues like thermal runaway, electrolyte leakage, and shuttle effects that can occur with liquid electrolytes.

Source