Query: Sulfide solid lithium ion anode

title: In Situ Ion Conducting Protective Layer Strategy to Stable Lithium Metal Anode for All Solid State Sulfide Based Lithium Metal Batteries

title: Flexible quasi solid state lithium ion capacitors employing amorphous SiO2 nanospheres encapsulated in nitrogen doped carbon shell as a high energy anode
abstract: Lithium ion hybrid capacitors (LICs) take the advantage of simultaneous high energy power output, and become increasingly important for next generation applications. Developing a high performing LICs with high energy power cycle combination remains a significant challenge due to low capacity intercalation electrodes, and kinetically sluggish alloying type electrodes. A strategy employing fast pseudocapacitive lithium ion storage in high capacity alloying type anode, rather than a bulk storage, can output kinetically superior LICs with high energy even at high power conditions. Herein, we demonstrate a highly interconnected 3 dimensional (3D) SiO2 nanospheres embedded Nitrogen doped carbon shell with fast lithium ion storage kinetics as high performing anode for LICs. As a result, LIC with a high energy (139 Wh kg 1) high power density (42 kW kg 1) and super stability (20,000 cycles) is obtained, outperforming previously studied alloying type metal oxide and sulfide anodes. A flexible LICs is further demonstrated which shows good stability under different bending conditions. The current research promotes the practical utilization of earth abundant material as a high capacity and high rate electrode for the next generation flexible and wearable devices.

title: X ray Photoelectron Spectroscopy Probing of the Interphase between Solid State Sulfide Electrolytes and a Lithium Anode
abstract: All solid state lithium ion batteries are considered as an alternative for next generation energy storage systems. Solid state electrolytes can improve the safety of lithium ion batteries by the re.

title: High conductivity free standing Li6PS5Cl/poly(vinylidene difluoride) composite solid electrolyte membranes for lithium ion batteries
abstract: Bulk type all solid state batteries (ASSBs) using sulfide solid electrolyte are considered as a promising alternative to commercial lithium ion batteries owing to their high energy density and safety. However, cell energy density is often comparatively low due to use of a thick solid electrolyte separator and a lithium alloy as anode. For achieving high performance ASSBs, creating a thin free standing electrolyte with high conductivity and good cycling stability against lithium anode is essential. In this work, we present Li6PS5Cl/poly(vinylidene difluoride) (LPSCl/PVDF) composite electrolytes prepared by a slurry method. The influence of the PVDF content on the microstructure, morphology, ionic conductivity and activation energy of the LPSCl/PVDF electrolytes is systematically investigated. Free standing LPSCl/PVDF membranes with a thickness of 100 120 mm and a high ionic conductivity of about 1*10 3 S cm 1 at 25 degC are obtained. After adding PVDF to the LPSCl electrolyte, the cycling stability of the LPSCl electrolyte against lithium metal improves significantly. Therefore, LPSCl/PVDF composite electrolytes are promising candidates to be used in ASSBs.

title: Advanced materials for energy conversion and storage: Low temperature, solid state conversion reactions of cuprous sulfide and the stabilization and application of titanium disilicide as a lithium ion battery anode material

title: Electrochemical Redox Behavior of Li Ion Conducting Sulfide Solid Electrolytes
abstract: The lithium phosphorus sulfide family of solid electrolytes has attracted much attention for applications in solid state batteries, as it exhibits some of the highest lithium ion conductivities of solid electrolytes to date. Here, we systematically assess the stability of the b Li3PS4 exemplar over a wide electrochemical window, from 0 to 5 V vs Li/Li+ that encompasses the potentials of all negative electrodes and most positive electrodes of interest for high energy density lithium batteries. By use of a unique cell construction in which the solid electrolyte is fabricated as an electroactive electrode by adding carbon as an electronic conductor, redox activity is amplified. The interphase (SEI) forming solid state reactions at high potential are found to be irreversible and passivating, whereas those occurring at low potential are reversible. This contrasts with the irreversible anode SEI formed at low potentials in lithium ion and lithium metal batteries and the general absence of an SEI at cathode pot.

title: A Quinone Anode for Lithium Ion Batteries in Mild Aqueous Electrolytes.
abstract: Aqueous batteries could be potentially used for grid scale energy storage due to the use of nonflammable electrolytes and long cycle life. Recently, quinones have shown examples as redox active materials in aqueous batteries in either strong acidic or basic conditions. However, a quinone based battery with a less corrosive electrolyte is still rare. Given that quinone based batteries are heavily influenced by the pH of electrolytes, we studied the influence of acid dissociation constants (pKa) of hydroquinones on their performance as solid electrode materials. We measured the p K a of anthracene 9,10 diol AQH2 and benzo[1,2 b:4,5 b']dithiophene 4,8 diol BDTDH2 of two para quinone monomers, i.e. anthracene 9,10 dione AQ and benzo[1,2 b:4,5 b']dithiophene 4,8 dione BDTD Subsequently, their polymeric forms, i.e. poly(anthraquinonyl sulfide) PAQS and poly(benzo[1,2 b:4,5 b']dithiophene 4,8 dione 2,6 diyl sulfide) PBDTDS were investigated as electrodes in aqueous lithium ion cells. At pH 13, PAQS demonstrates a low capacity and poor cycle life, while PBDTDS shows a capacity of 196 mAh g 1 and fade rates of 0.0038%/cycle over 4200 cycles, 0.77%/day over 21 days. The differences in capacity and cycle stability can be explained by the difference of corresponding pKa values. A full cell shows a voltage of 1.08 V, a capacity of 72 mAh g 1 and ~99.9% of Coulombic efficiency for 500 stable cycles.

title: Single step prepared Li2S P2S5 C composite cathode for high areal capacity all solid state lithium ion batteries
abstract: All solid state batteries (ASSBs) consisting of a Li2S P2S5 C composite cathode, sulfide based glass (Li2SP2S5) and an In anode are prepared via a single step cathode preparation method. The great advantage of the single step preparation is that the solid electrolyte synthesis process is carried out simultaneously with the process for preparing the composite cathode. This improves the cathode morphology and the three phase distribution and saves preparation time. The results of impedance spectroscopy and the galvanostatic intermittent titration technique indicate that making ASSBs with the single step cathode brings about a much lower charge transfer and interfacial resistance compared to that with the two step cathode, which is due to the improved electrode microstructure. Consequently, an ASSB with a single step cathode demonstrates higher charge discharge capacities. Moreover, much higher ~8 times higher) areal capacities are achieved in comparison with the reported values while the reasonable gravimetric capacities are maintained. Thus, it can be said that the single step preparation method is effective for achieving high area capacity in all solid state Li2S P2S5 batteries.

title: An Air Stable and Dendrite Free Li Anode for Highly Stable All Solid State Sulfide Based Li Batteries
abstract: Li metal is an attractive anode material for all solid state lithium batteries (ASSLBs) because of its high specific capacity (3860 mAh g 1) and low electrochemical potential 3.04 V vs the standard hydrogen electrode)[1 4] Moreover, the use of intrinsically nonflammable inorganic solid state electrolytes (SSEs) can theoretically solve the safety issue associated with thermal runaway.[3,4] Various SSEs have been recently developed, including oxide sulfide halide and borohydride based SSEs. Sulfide based SSEs have emerged as one of the most promising candidates for use in ASSLBs due to their mechanical properties and ultrahigh ionic conductivity which can reach as high as 10 2 S cm 1 at room temperature.[5 8] However, pure Li metal is still unsuitable for realapplication in sulfide based ASSLBs due to the side reactions at the interface. Similar to conventional liquid based lithium ion batteries, the first major obstacle for the use of Li metal anodes is the penetration of Li dendrites through the sulfide based SSEs, which raises safety concerns and often results in the decay of battery performance or even short circuit.[9,10] Among the typical sulfide based SSEs, such as Li10GePS12, Li3PS4 (glass or ceramic)[13 17] and Li6PS5X (X Cl, Br, I)[18,19] the formation of lithium dendrites in Li3PS4 system is well recognized.[13 16,20,21] It is proposed that the voids and grain boundaries within the SSEs, as well as the insufficient interfacial contact between Li and SSEs are the two main reasons for lithium dendrite formation in sulfide based ASSLBs.[16,22] Thus, there should be a critical current density at which short circuiting of the cell occurs in the Li2S P2S5 solid electrolyte system.[14,15] However, recent reports indicate that the Li dendrites can be formed in Li4Ti5O12/Li2S P2S5/ Li[20] and Se/Li3PS4/Li ASSLBs using bare Li as the anode, even at a low current density of 50 mA g 1. Another possible reason proposed by Wang and co workers is the relatively high electronic conductivity (10 9 10 8 S cm 1) of Li3PS4. Though not fully understood yet, the introduction of additives into SSEs similar to Li protection in liquid batteries have been developed. For example, LiI,[16] LiF,[23] and P2O5 have been introduced into Li3PS4 and proven to be effective suppressing lithium Li metal is a promising anode material for all solid state batteries, owing to its high specific capacity and low electrochemical potential. However, direct contact of Li metal with most solid state electrolytes induces severe side reactions that can lead to dendrite formation and short circuits. Moreover, Li metal is unstable when exposed to air, leading to stringent processing requirements. Herein, it is reported that the Li3PS4/Li interface in all solid state batteries can be stabilized by an air stable LixSiSy protection layer that is formed in situ on the surface of Li metal through a solution based method. Highly stable Li cycling for over 2000 h in symmetrical cells and a lifetime of over 100 cycles can be achieved for an all solid state LiCoO2/Li3PS4/Li cell. Synchrotron based high energy X ray photoelectron spectroscopy in depth analysis demonstrates the distribution of different components within the protection layer. The in situ formation of an electronically insulating LixSiSy protection layer with highly ionic conductivity provides an effective way to prevent Li dendrite formation in high energy all solid state Li metal batteries.

title: High performance Li6PS5Cl based all solid state lithium ion batteries
abstract: All solid state lithium ion batteries (ASSLIBs) owing to their advantage of enhanced safety are considered to be a promising candidate for next generation energy storage devices. However, the poor cycling performance and low areal capacities of ASSLIBs with S, Li2S or traditional oxide cathodes hinder the development of high energy density ASSLIBs. Herein, a Li6PS5Cl solid state electrolyte has been systematically investigated for use as a cathode active material in ASSLIBs for the first time. ASSLIBs employing Li6PS5Cl as both the active material and electrolyte with a Li In alloy anode are fabricated. A Li6PS5Cl based cell with an active material loading of 3.1 mg cm 2 exhibits a high discharge capacity of around 535 mA h g 1 after 650 cycles at 56 mA g 1 ~0.1C) at room temperature, which is the highest value among ASSLIBs using sulfide SSEs as active materials and is even comparable with those of cells with S, Li2S or transition metal sulfides as the active material. This superior long term cycling performance is attributed to the highly reversible electrochemical activity of Li6PS5Cl revealed by ex situ XRD and XPS analyses.