Anthraquinonyl Sulfide Research Articles

Influence of alkali metal ions (Li+, Na+, and K+) on the redox thermodynamics and kinetics of organic electrode materials for rechargeable batteries

Organic electrode materials have been widely applied in rechargeable Li, Na, and K batteries. However, one of the key scientific issues—the influence of Li+, Na+, and K+ ions on the redox thermodynamics and kinetics is still unclear. Herein, by using n-type poly(anthraquinonyl sulfide) (PAQS) and polyimide (PI) and p-type polytriphenylamine (PTPAn) as examples, we have systematically and deeply studied this problem though elaborate electrochemical tests and theoretical calculations. By employing three-electrode cells, the thermodynamic potentials of Li, Na, K metal electrodes as well as the PAQS, PI, and PTPAn organic electrodes have been accurately measured. They follow the order of Li+ > Na+ > K+ for PAQS and PI, and keep unchanged for PTPAn. As an application of this discovery, PAQS–PTPAn dual-ion full-cells show the highest output voltage and low-temperature performance with K+ ion. To explain the tendency, universal thermodynamic models have been established and the theoretical calculations reveal that with the increase of ionic radius, the interactions of metal ion with electrolyte solvent and discharged n-type organic (N–) become weaker, which lower down the thermodynamic potential and enhance the redox kinetics. This work provides a significant guidance for the design of high-performance organic batteries.

Interwoven Poly(Anthraquinonyl Sulfide) Nanosheets‐Decorated Carbon Nanotubes as Core–Sheath Heteroarchitectured Cathodes for Polymer‐Based Asymmetrical Full Batteries

Organic redox‐active polymers provide promising alternatives to metal‐containing inorganic compounds in Li‐ion batteries (LIBs), whereas suffer from low actual capacities, poor rate/power capabilities, and inferior cycling stability. Herein, poly(anthraquinonyl sulfide)‐coated carbon nanotubes (CNT@PAQS) are readily performed by in situ polymerization to form core–sheath nanostructures. Remarkably, flower‐like PAQS nanosheets are interwoven around CNTs to synergistically create robust 3D hierarchical networks with abundant cavities, internal channels, and sufficiently‐exposed surfaces/edges, thereby promoting electron transport and making more active sites accessible for electrolytes and guest ions. Apparently, the as‐fabricated CNT@PAQS cathode delivers the large reversible capacity (200.5 mAh g−1 at 0.05 A g−1), high‐rate capability (161.5 mAh g−1 at 5.0 A g−1), and impressive cycling stability (retaining 88.0% over 1000 cycles). In addition, an asymmetric full‐battery using CNT@PAQS as a cathode and cyclized polyacrylonitrile‐encapsulated CNTs as an anode is assembled that delivers a high energy density of 86.3 Wh kg−1, and retains 81.3% of initial capacity after 1000 cycles. This work opens up an efficient strategy to combine highly conductive and redox‐active phases into core–sheath heterostructures to unlock the barrier of high‐rate charge storage. The further integration of two polymer‐based electrodes into asymmetric full cells would also consolidate the development of low‐cost, sustainable, and powerful batteries.

Unveiling True Limits of Electrochemical Performance of Organic Cathodes in Multivalent Batteries through Cyclable Symmetric Cells

AbstractMultivalent batteries are often hyped as a next‐generation high‐energy density battery technology, but in reality, both literature reports and practical research are plagued by poor reproducibility of electrochemical results. Within the present work, we take a look at the electrochemical testing of organic cathodes that can be used with a variety of mono‐ and multivalent cations and propose a cyclable symmetric cell approach, already applied to the field of lithium‐ion batteries. By using a model organic system based on poly(anthraquinonyl sulfide) (PAQS) active material, we demonstrate that the symmetric cell approach elegantly removes the limitations of multivalent metal anodes, and for the first time, reveals the full potential of organic cathodes in multivalent batteries. Furthermore, symmetric cells enable reliable EIS measurements on organic cathodes and open a pathway to optimize electrochemical/transport parameters through the design of next‐generation organic cathode materials and advanced electrode design(s). We suggest that the cyclable symmetric cell approach should be generally applicable in multivalent and all other batteries where electrochemical characterization requires the elimination of the counter electrode contribution.

Effect of Carbon Additives on the Rate Performance of Redox Polymer Materials for Lithium Metal Batteries

Materials with fast charging and discharging capability are highly desirable for the development of high-power batteries. In this study, we present a composite consisting of a poly(anthraquinonyl sulfide) and reduced graphene oxide (PAQS@rGO). The composite is synthesized by an in situ method and aims to be used as a high-power electrode material for lithium metal batteries. Other carbon additives including Ketjen black and activated carbon are also investigated as a comparison. The results suggest that the high electronic conductivity of the rGO and its unique morphology serving as anchor sites render it the optimal additive for the polymer. Highly reversible capacity and stable cyclability are obtained with the PAQS@rGO sample. The advantages of the in situ synthesis method over the simple mixing method for the preparation of the polymer composite are also explored. A better contact between the polymer and the carbon additives and thus lower polarization (IR) is achieved with the in situ synthesis method. Although the rGO additive improves the electronic conductivity of the composite, a proper amount of conductive carbon additives is still necessary for the full utilization of the composite. Since the PAQS@rGO composites possess a porous honeycomb morphology, small particles of carbon black are able to penetrate into the pores and thus build a better electron transfer network than the crumpled rGO sheet. This in situ synthesis with rGO as carbon additives is proven to be a universal method for the preparation of similar polymers.

The Mechanism of Modification of Poly(anthraquinonylsulfide) Organic Electrode Materials

AbstractOrganic electrode materials have received much attention in recent years, but their solubility of organic affects the capacity of the battery and the cycling performance. The solubility can be effectively reduced by polymerization, which can improve the stability of the material, but the capacity of organic polymer materials generally decreases with an increase in molar mass. In this study, poly(anthraquinonyl sulfide) (PAQS) is strongly oxidized, and its morphological characteristics and active sites are found to change without affecting its solubility, leading to enhanced the battery capacity and stability performance. The experimental results show that PAQS is converted into micro‐sized spherical particles after being treated with H2SO4 solution.This process changes the sulfone group structure of PAQS and increases its active site S=O bond. Calculations show that the adsorption energy of the S=O active site is more stable than that of the original C=O active site, making it easier for the S=O group to adsorb cations. At the same time, the conductivity of PAQS increases after the treatment. The experimental results show that the capacity of the battery is 128.3 mAhg−1 at a current rate of 2 C when the strongly oxidized PAQS is used as the negative electrode, while the initial capacity was only 84.3 mAhg−1 under the same test conditions before the treatment.

Molecular engineering of dihydroxyanthraquinone-based electrolytes for high-capacity aqueous organic redox flow batteries

Aqueous organic redox flow batteries (AORFBs) are a promising technology for large-scale electricity energy storage to realize efficient utilization of intermittent renewable energy. In particular, organic molecules are a class of metal-free compounds that consist of earth-abundant elements with good synthetic tunability, electrochemical reversibility and reaction rates. However, the short cycle lifetime and low capacity of AORFBs act as stumbling blocks for their practical deployment. To circumvent these issues, here, we report molecular engineered dihydroxyanthraquinone (DHAQ)-based alkaline electrolytes. Via computational studies and operando measurements, we initially demonstrate the presence of a hydrogen bond-mediated degradation mechanism of DHAQ molecules during electrochemical reactions. Afterwards, we apply a molecular engineering strategy based on redox-active polymers to develop capacity-boosting composite electrolytes. Indeed, by coupling a 1,5-DHAQ/poly(anthraquinonyl sulfide)/carbon black anolyte and a [Fe(CN)6]3−/4− alkaline catholyte, we report an AORFB capable of delivering a stable cell discharge capacity of about 573 mAh at 20 mA/cm2 after 1100 h of cycling and an average cell discharge voltage of about 0.89 V at the same current density.

Poly(Anthraquinonyl Sulfide)/CNT Composites as High-Rate-Performance Cathodes for Nonaqueous Rechargeable Calcium-Ion Batteries.

Calcium‐ion batteries (CIBs) are considered as promising alternatives in large‐scale energy storage due to their divalent electron redox properties, low cost, and high volumetric/gravimetric capacity. However, the high charge density of Ca2+ contributes to strong electrostatic interaction between divalent Ca2+ and hosting lattice, leading to sluggish kinetics and poor rate performance. Here, in situ formed poly(anthraquinonyl sulfide) (PAQS)@CNT composite is reported as nonaqueous calcium‐ion battery cathode. The enolization redox chemistry of organics has fast redox kinetics, and the introduction of carbon nanotube (CNT) accelerates electron transportation, which contributes to fast ionic diffusion. As the conductivity of the PAQS is enhanced by the increasing content of CNT, the voltage gap is significantly reduced. The PAQS@CNT electrode exhibits specific capacity (116 mAh g−1 at 0.05 A g−1), high rate capacity (60 mAh g−1 at 4 A g−1), and an initial capacity of 82 mAh g−1 at 1 A g−1 (83% capacity retention after 500 cycles). The electrochemical mechanism is proved to be that the PAQS undergoes reduction reaction of their carbonyl bond during discharge and becomes coordinated by Ca2+ and Ca(TFSI)+ species. Computational simulation also suggests that the construction of Ca2+ and Ca(TFSI)+ co‐intercalation in the PAQS is the most reasonable pathway.

High-performance Mg–organic batteries based on hybrid MgCl2–LiCl/THF electrolytes

Rechargeable magnesium batteries (RMBs) are regarded as one of the promising candidates of next generation of battery technologies, but seriously hampered by the sluggish kinetics of Mg2+-related cathode reactions. A pertinent solution is adding Li salt into the electrolyte to build a hybrid Mg/Li battery (MLB), which combines the high safety of Mg anode and the fast reaction kinetics of Li+ with the cathode material. Herein, we propose a novel, simple, and cheap dual-salt electrolyte for MLBs, namely MgCl2–LiCl/THF, based on the exceptional synergetic effect between MgCl2 and LiCl in THF. The 1.0 M electrolyte demonstrated desired ionic conductivity (1.3 mS cm–1), good compatibility with Mg anode, and adequate oxidation potential (2.2 V vs. Mg) for typical organic cathode materials including poly(anthraquinonyl sulfide) (PAQS), poly(1,4-anthraquinone) (P14AQ), and dilithium salt of poly(2,5-dihydroxy-p-benzoquinonyl sulfide) (Li2PDHBQS). Unlike PAQS and P14AQ adopting MgCl+ as inserted cation, Li2PDHBQS selected Li+ to participate in the reaction. Therefore it demonstrated superior electrochemical performance to most of previously reported inorganic and organic cathode materials for MLBs, including a high reversible capacity (282 mAh g−1), a high rate capability (72% @ 2000 mA g−1), and a high cycling stability (70% @ 500th cycle). The combination of MgCl2–LiCl/THF electrolyte and Li2PDHBQS cathode provides not only a successful example of high-performing and affordable MLBs, but also insights of ionic species in the electrolytes and their interactions with organic cathode materials, which are very significant for the further development of RMBs.

A high-performance organic cathode customized for sulfide-based all-solid-state batteries

All-solid-state batteries (ASSBs) have become increasingly attractive recently due to their better safety and prospective long-term stability compared with conventional liquid batteries. However, obtaining a sustainable cathode candidate to match the solid electrolyte with regards to operating potential, chemical compatibility, and mechanical property is still an open challenge. Herein, the chemical incompatibility of quinone-based active materials and sulfide-based electrolyte were unveiled for the first time through a heteroconjugate addition reaction mechanism. To develop a quinone cathode customized for sulfide-based ASSBs, poly-(anthraquinonyl sulfide)-graphene (PAQS-G) nanocomposite was reported. The stable polymer framework of PAQS can protect the quinone redox center by preventing nucleophilic attack from sulfide-based solid electrolytes. The graphene additives can ameliorate redox kinetics and improve active material utilization. The PAQS-G cathode exhibited a specific capacity of ∼178 mAh g−1 and a high material utilization of ∼79%. Excellent cycling stability was achieved with 94 % capacity after 200 cycles in lithium batteries and 95.5 % capacity after 300 cycles in sodium batteries at 0.1C rate, respectively. A promising potential for energy storage applications was demonstrated.

Low-cost carbonyl polymer design for high-performance lithium-organic battery cathodes

Carbonyl polymers, such as poly(anthraquinonyl sulfide) (PAQS) and poly(benzoquinonyl sulfide) (PBQS), are typically selected as cathode materials for lithium-organic batteries (LOBs) because of their inherent high theoretical capacity and low solubility in the electrolyte. However, their commercialization is hindered by their relatively complex synthesis routes, low yields, and high cost. Herein, a carbonyl polymer poly(piperazine-alt-benzoquinone) (NP2), obtained from the polymerization of vanillin and piperazine with oxidative amination at the theoretical production cost of US $0.48 per gram, exhibits a high reversible capacity of 257 mAh g−1, leading to a cost performance of US $0.19 per 100 mAh, which is superior to the reported carbonyl polymers. Furthermore, ex situ X-ray photoelectron spectroscopy and ex situ and in situ Fourier-transform infrared measurements release the reversible electrochemical reaction mechanism of NP2 based on carbonyl redox chemistry. This study demonstrates a simple and effective strategy to synthesize low-cost carbonyl polymers, which will pave the way for their future application in high-performance LOBs.

Liquid Ammoniates as Efficient Electrolytes for Room-Temperature Rechargeable Sodium-Metal Batteries Based on an Organic Cathode

The development of room-temperature rechargeable sodium-metal batteries (SMBs) has gathered enormous interest as they are an attractive option to develop cost-effective devices to store energy from renewable sources. However, one of their main constraints is the high reactivity of sodium with most of the electrolytes commonly employed, which hampers finding an optimized SMB configuration. Here, we describe the use of a highly concentrated electrolyte based on liquid ammonia and sodium iodide. Its formulation is NaI·3.3NH3, and it confers metallic sodium high stability at room temperature. Moreover, the electrolyte is significantly more cost-effective than typical organic or ionic liquid electrolytes. Here, the advantages of this electrolyte are shown in a battery based on the combination of sodium metal as an anode and poly(anthraquinonyl sulfide) (PAQS) as a cathode. This combination leads to an experimental capacity of 218 mA·h·g–1 at 5C (reaching 97% of the theoretical capacity) at room temperature and maintains a Coulombic efficiency close to 100% over 300 cycles. In addition, the system described here attains, after 100 cycles, specific energies over 320 W·h·kgPAQS–1 and a specific power of 3500 W·kgPAQS–1, with an energy efficiency over 90%. These metrics, which compare favorably with those of typical organic electrolytes, are linked to an extremely low value of the charge-transfer resistance at the cathode/ammoniate interphase. Despite the dissolution of PAQS during the reduction process, the battery already presents a capacity retention over 80% after 150 cycles at 5C.

Electrochemically active layer on the surface of poly(anthraquinonyl sulfide) anode in dual-ion batteries

The dissolution characteristics of organic electrode materials, which are widely used in metal-ion, solid-state, and dual-ion batteries, affect the cycle performance of batteries. In this study, poly(anthraquinonyl sulfide), natural graphite, and N-propyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide ionic liquid are used as the anode, cathode, and electrolyte, respectively, to construct a dual-ion battery. Experiments reveal that when two glass fiber layers are used as separator in this battery, they significantly affect its performance, and the discharge capacity and retention rate of the cell are 47.4 mAh g−1 and 91.4%, respectively, after 100 cycles at the current rate of 2C. In addition, the self-discharge effect is greatly reduced. The glass fiber layer next to the poly(anthraquinonyl sulfide) anode is analyzed using scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and cyclic voltammetry. The results indicate that the poly(anthraquinonyl sulfide) particles form an electrochemically active layer, which was attached to the glass fiber and can participate in electrochemical reactions. The formation of the electrochemically active layer improves the electrochemical performance of the dual-ion battery.

A Quinone Anode for Lithium-Ion Batteries in Mild Aqueous Electrolytes.

Aqueous batteries could be potentially used for grid-scale energy storage owing to the use of nonflammable electrolytes and long cycle life. Recently, quinones have shown examples as redox-active materials in aqueous batteries under 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 pKa of anthracene-9,10-diol (AQH2 ) and benzo[1,2-b:4,5-b']dithiophene-4,8-diol (BDTDH2 ) from the Pourbaix diagrams 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, whereas PBDTDS shows a capacity of 196 mAh g-1 and fade rates of 0.0038 % per cycle over 4200 cycles, 0.77 % per day over 21 days. The differences in capacity and cycle stability can be explained by the difference of corresponding pKa values. A full cell with the configuration of (-)PBDTDS|2.5 m Li2 SO4 (pH 13)|LiCoO2 (+) shows a voltage of 1.08 V, a capacity of 72 mAh g-1 and ≈99.9 % of Coulombic efficiency for 500 stable cycles.

A High Energy Density Self-supported and Bendable Organic Electrode for Redox Supercapacitors with a Wide Voltage Window

Redox-active organic electrode materials are highly desirable in realizing next-generation all-in-one bendable electronic systems. Herein, a novel flexible supercapacitors (SCs) electrode is fabricated from poly(anthraquinonyl sulfide) (PAQS) and single-walled carbon nanotubes (SWCNTs) suspension by a simple vacuum filtration and named as PAQS-SWCNTs. The PAQS-SWCNTs electrode offered an initial capacitance of 223 F-g−1 and outstanding capacitance retention up to 78.4% after 3 × 104 charge-discharge cycles at 0.5 A-g−1 current density. In a high potential range (0-3 V) and aprotic electrolyte, the PAQS-SWCNTs electrodes in coin cell exhibited an outstanding energy density of 69 Wh-kg−1 at a power density of 90.6 W-kg−1, whereas in the fabricated flexible SCs it retained 63.2 Wh-kg−1. The PAQS-SWCNTs electrodes also showed extraordinary performance at a higher current density (20 A-g−1) and maintained a specific capacitance of 55 and 47 F-g−1 for coin and flexible SCs, respectively. Moreover, the flexible SC is further verified to be able to illuminate up multiple LEDs. These futuristic findings showed that the SCs assembled with flexible PAQS-SWCNTs electrodes have potential application in energy-storage devices and make them highly appealing for future redox supercapacitors.

Significantly stable organic cathode for lithium-ion battery based on nanoconfined poly(anthraquinonyl sulfide)@MOF-derived microporous carbon

The organic materials are auspicious alternative to the inorganic counterparts as cathode materials for lithium-ion batteries (LIBs) owing to their unusual capacity and sustainability. However, the widespread application of organic cathode in most of the cases have been hampered by their intrinsically easy solubility in electrolyte and natural insulating property, resulting in the poor practical capacity and low rate capacity. Herein, we demonstrate the rational ‘ship in bottle’ strategy to overcome these problems by confining the organic materials into microporous host. Poly(anthraquinonyl sulfide) (PAQS) was successfully polymerized inside a MOF-derived 3D microporous carbon (3D-C) to obtain PAQS@3D-C via ‘ship in bottle’ strategy. The novel organic cathode for LIBs shows a higher reversible specific capacity of 219 mAh g−1 at 0.2 C and greatly improved cycle life with low capacity fading speed of ∼0.015% per cycle. Specifically, PAQS@3D-C shows a remarkable high-rate capacity of 112 mAh g−1 even at 20 C. The superior electrochemical performance is mainly ascribed to the novel structure via ‘ship in bottle’ strategy. This unveils efficient pathways for the development of new generation super-stable organic cathode materials with excellent battery performance.

A Bifunctional and Free‐Standing Organic Composite Film with High Flexibility and Good Tensile Strength for Tribological and Electrochemical Applications

AbstractWith the development of flexible electronics, flexible lithium‐ion batteries (LIBs) have attracted fabulous attention in the emerging field of wearable and bendable electronic system. The performance of flexible batteries during deformation mainly depends on the electrode flexibility with high mechanical properties. Herein, for the first time, the tribological and electrochemical applications of a flexible organic composite film made of poly(anthraquinonyl sulfide) and single‐wall carbon nanotubes (PAQS‐SWCNTs) are systematically investigated. By employing the tribological measurements and tracking the worn surfaces, the PAQS‐40% SWCNTs film show high adhesive phenomenon with 50% and ≈80% reduction in coefficient of friction (COF) and specific wear rate. As a flexible organic cathode in LIBs, the same film delivers an initial capacity of 194 mAh g−1at 0.1 C and retains almost the same capacity when it is backtested at 0.1 C. Moreover, the PAQS‐40% SWCNTs cathode retains 81.1% of its initial capacity after 406 cycles with a current speed of 0.5 C. Simulated results show the more stable properties of PAQS with two Li‐ion insertions (PAQS‐2Li+) than the monolithiated PAQS (PAQS‐1Li+) in virtue of its highest negative binding energies. A prototype flexible lithium battery is assembled, which delivers an initial capacity of 151 mAh g−1, respectively.

Poly(anthraquinonyl sulfides): High Capacity Redox Polymers for Energy Storage.

Redox polymers with high energy storage capacity are searched in order to diminish the weight to the actual batteries. Poly(anthraquinonyl sulfide) PAQS is a popular redox polymer which has shown a high performance cathode for lithium, sodium and magnesium batteries. Although PAQS cathodes show high cycling stability it has a relatively low theoretical specific capacity of 225 mAh/g. In this paper we show the synthesis and characterization of new poly(anthraquinonyl sulfides) PAQxS in an attempt to improve the specific capacity of PAQS. Thus, a series of PAQxS polymers with different polysulfide segment lengths (x between 2 and 9 sulfur atoms) have been synthesized in high yields by reacting in situ formed sodium polysulfides with 1,5-dicholoroanthraquinone. The poly(anthraquinonyl sulfides) powders were characterized by ATR-FTIR, solid state 13C NMR for the organic part and Raman spectroscopy for the chalcogenide part. This characterization confirmed the chemical structure of the PAQxS based on an anthraquinone moiety bind together by polysulfide segments. The electrochemical characterization showed a dual reversible redox mechanism associated with both the anthraquinone and polysulfide electrochemistry. Finally, lithium coin cell battery test of the PAQxS redox polymers as cathodes indicated that the capacity of poly(anthraquinonyl sulfides) showed very high experimental initial capacity values above 600 mAh/g, less capacity loss than sulfur cathodes, and higher steady state capacity than PAQS.

Probing electrochemical reactions in organic cathode materials via in operando infrared spectroscopy

Organic materials are receiving an increasing amount of attention as electrode materials for future post lithium-ion batteries due to their versatility and sustainability. However, their electrochemical reaction mechanism has seldom been investigated. This is a direct consequence of a lack of straightforward and broadly available analytical techniques. Herein, a straightforward in operando attenuated total reflectance infrared spectroscopy method is developed that allows visualization of changes of all infrared active bands that occur as a consequence of reduction/oxidation processes. In operando infrared spectroscopy is applied to the analysis of three different organic polymer materials in lithium batteries. Moreover, this in operando method is further extended to investigation of redox reaction mechanism of poly(anthraquinonyl sulfide) in a magnesium battery, where a reduction of carbonyl bond is demonstrated as a mechanism of electrochemical activity. Conclusions done by the in operando results are complemented by synthesis of model compound and density functional theory calculation of infrared spectra.

Poly(anthraquinonyl sulfide) cathode for potassium-ion batteries

Potassium-ion batteries (KIBs) are a promising sustainable energy storage technology due to the high abundance and low cost of potassium. Carbon anode materials for KIBs have seen great successes, but the development of cathode materials is yet to catch up. In this study, poly(anthraquinonyl sulfide) (PAQS) is evaluated as a cathode material for KIBs. It exhibits a high reversible capacity of 200mAh/g, which is the highest value for a potassium storage cathode material. The cell shows two slopes averaged at 2.1 and 1.6V vs. K+/K. It shows a good cycling performance with the capacity retention of 75% after 50cycles at a rate of C/10. These preliminary results indicate that PAQS is a promising cathode material for KIBs.

An All-solid-state and All-organic Sodium-ion Battery based on Redox-active Polymers and Plastic Crystal Electrolyte

A solid state Na+ electrolyte is developed by dissolving Na+ salts into the organic crystal succinonitrile, which exhibits a high ionic conductivity of ∼10−3 Scm−1 at room temperature and a wide electrochemical window of >3V. Based on this solid-state electrolyte, an all-organic Na–ion battery is constructed by use of poly(aniline/o-nitroaniline) (P(AN-NA)) cathode and poly(anthraquinonyl sulfide) (PAQS) anode. This solid-state battery works well with an open circuit voltage of 2.4V and can be cycled at considerable high rate of >800mAg−1, showing a competitive performance to the organic solvent Na-ion batteries.