Composite Polymer Electrolyte Research Articles

Rationally coordinating polymer enabling effective Li-ion percolation network in composite electrolyte for solid-state Li-metal batteries

The sluggish lithium-ion mobility and inferior electrolyte/electrode interfacial compatibility of composite solid electrolytes greatly hinder the practical application of solid-state lithium-metal batteries. Here, a novel composite polymer electrolyte (CPE) with effective Li+ percolation network is synthesized based on single-ion conductive polymer lithiated polyvinyl formal (LiPVFM) and garnet Li6.4La3Zr2Ga0.2O12 (LLZGO) nanoparticles. The supramolecular interaction between the branched hydroxyl in LiPVFM and the lattice oxygen in LLZGO fillers endows CPE with a continuous percolation structure and improved toughness. Meanwhile, the rational O-Li+ coordination in the LiPVFM random polymer significantly enhances Li+ transfer within the percolation network. Therefore, this as-prepared CPE presents a lithium-ion transference number of 0.75 and an ionic conductivity of 0.527 mS cm−1 at 30 °C, alongside an electrochemical stability window of 4.6 V and a substantial suppression of Li dendrite growth. In addition, ultra-stable interfaces between this CPE and high-voltage LiNi0.6Mn0.2Co0.2O2 (NMC) cathode during cycling can be determined by in-situ electrochemical impedance spectroscopy and in-situ differential electrochemical mass spectrometry characterization. This work is a new exploration for the structural design of CPEs and highlights the importance of “rational coordination” of alkali cation in solid batteries.

Enhancement mechanism of the comprehensive performance of all-solid-state polymer electrolytes by halloysite nanotubes: Construction of efficient lithium-ion conduction channels

Considering the current issues with poly(ethylene oxide)-based all-solid-state polymer electrolytes (PEO-ASSPEs) employed in lithium-ion batteries (LIBs), such as low ionic conductivity, low lithium-ion transference number, narrow electrochemical stability window, and poor cyclic stability. This study introduces oxygen-vacancy-rich halloysite nanotubes (HNTs) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) into the PEO matrix to fabricate a flexible composite polymer electrolyte (CPEs) via a solvent-free method. The interaction between HNTs and LiTFSI in the PEO matrix serves to mitigate the ionic solvation effect, increase the number of free lithium-ion, and reduce the lithium-ion migration energy barrier. Additionally, the internal framework formed by the mutual stacking of HNTs reduces the number of entanglements in polymer molecular chains, enhances the mobility of the chains, and generates a continuous interface effect, forming fast lithium-ion transport channels. The CPEs prepared in this study are in conformity with the Vogel-Tammann-Fulcher (VTF) empirical equation. The CPE containing 10 wt% HNTs exhibits a high ionic conductivity (7.15 × 10−4 S cm−1) at 25 °C, a high lithium-ion transference number (0.600), a wide electrochemical stability window (5.5 V), and excellent cyclic performance (capacity retention of 82.02 % after 100 cycles at 0.1C), satisfying the electrochemical performance requirements for ASSPEs in LIBs.

Sandwich-type composited solid polymer electrolytes to strengthen the interfacial ionic transportation and bulk conductivity for all-solid-state lithium batteries from room temperature to 120 °C

The insurmountable charge transfer impedance at the Li metal/ solid polymer electrolytes (SPEs) interface at room temperature as well as the ascending risk of short circuits at the operating temperature higher than the melting point, dominantly limits their applications in solid-state batteries (SSBs). Although the inorganic filler such as CeO2 nanoparticle content of composite solid polymer electrolytes (CSPEs) can significantly reduce the enormous charge transfer impedance at the Li metal/SPEs interface, we found that the required content of CeO2 nanoparticles in SPEs varies for achieving a decent interfacial charge transfer impedance and the bulk ionic conductivity in CSPEs. In this regard, a sandwich-type composited solid polymer electrolyte with a 10% CeO2 CSPEs interlayer sandwiched between two 50% CeO2 CSPEs thin layers (sandwiched CSPEs) is constructed to simultaneously achieve low charge transfer impedance and superior ionic conductivity at 30 °C. The sandwiched CSPEs allow for stable cycling of Li plating and stripping for 1000 h with 129 mV polarized voltage at 0.1 mA cm−2 and 30 °C. In addition, the LiFePO4/Sandwiched CSPEs /Li cell also exhibits exceptional cycle performance at 30 °C and even elevated 120 °C without short circuits. Constructing multi-layered CSPEs with optimized contents of the inorganic fillers can be an efficient method for developing all solid-state PEO-based batteries with high performance at a wide range of temperatures.

The Versatile Establishment of Charge Storage in Polymer Solid Electrolyte with Enhanced Charge Transfer for LiF‐Rich SEI Generation in Lithium Metal Batteries

AbstractThe solid‐state electrolyte interface (SEI) between the solid‐state polymer electrolyte and the lithium metal anode dramatically affects the overall battery performance. Increasing the content of lithium fluoride (LiF) in SEI can help the uniform deposition of lithium and inhibit the growth of lithium dendrites, thus improving the cycle stability performance of lithium batteries. Currently, most methods of constructing LiF SEI involve decomposing the lithium salt by the polar groups of the filler. However, there is a lack of research reports on how to affect the SEI layer of Li‐ion batteries by increasing the charge transfer number. In this study, a porous organic polymer with “charge storage” properties was prepared and doped into a polymer composite solid electrolyte to study the effect of sufficient charge transfer on the decomposition of lithium salts. The results show in contrast to porphyrins, the unique structure of POF allows for charge transfer between each individual porphyrin. Therefore, during TFSI− decomposition to the formation of LiF, TFSI− can obtain sufficient charge, thereby promoting the break of C−F and forming the LiF‐rich SEI. Compared with single porphyrin (0.423 e−), POF provides 2.7 times more charge transfer to LiTFSI (1.147 e−). The experimental results show that Li//Li symmetric batteries equipped with PEO‐POF can be operated stably for more than 2700 h at 60 °C. Even the Li//Li (45 μm) symmetric cells are stable for more than 1100 h at 0.1 mA cm−1. In addition, LiFePO4//PEO‐POF//Li batteries have excellent cycling performance at 2 C (80 % capacity retention after 750 cycles). Even LiFePO4//PEO‐POF//Li (45 μm) cells have excellent cycling performance at 1 C (96 % capacity retention after 300 cycles). Even when the PEO‐base is replaced with a PEG‐base and a PVDF‐base, the performance of the cell is still significantly improved. Therefore, we believe that the concept of charge transfer offers a novel perspective for the preparation of high‐performance assemblies.

The Versatile Establishment of Charge Storage in Polymer Solid Electrolyte with Enhanced Charge Transfer for LiF-Rich SEI Generation in Lithium Metal Batteries.

The solid-state electrolyte interface (SEI) between the solid-state polymer electrolyte and the lithium metal anode dramatically affects the overall battery performance. Increasing the content of lithium fluoride (LiF) in SEI can help the uniform deposition of lithium and inhibit the growth of lithium dendrites, thus improving the cycle stability performance of lithium batteries. Currently, most methods of constructing LiF SEI involve decomposing the lithium salt by the polar groups of the filler. However, there is a lack of research reports on how to affect the SEI layer of Li-ion batteries by increasing the charge transfer number. In this study, a porous organic polymer with "charge storage" properties was prepared and doped into a polymer composite solid electrolyte to study the effect of sufficient charge transfer on the decomposition of lithium salts. The results show in contrast to porphyrins, the unique structure of POF allows for charge transfer between each individual porphyrin. Therefore, during TFSI- decomposition to the formation of LiF, TFSI- can obtain sufficient charge, thereby promoting the break of C-F and forming the LiF-rich SEI. Compared with single porphyrin (0.423 e-), POF provides 2.7 times more charge transfer to LiTFSI (1.147 e-). The experimental results show that Li//Li symmetric batteries equipped with PEO-POF can be operated stably for more than 2700 h at 60 °C. Even the Li//Li (45 μm) symmetric cells are stable for more than 1100 h at 0.1 mA cm-1. In addition, LiFePO4//PEO-POF//Li batteries have excellent cycling performance at 2 C (80 % capacity retention after 750 cycles). Even LiFePO4//PEO-POF//Li (45 μm) cells have excellent cycling performance at 1 C (96 % capacity retention after 300 cycles). Even when the PEO-base is replaced with a PEG-base and a PVDF-base, the performance of the cell is still significantly improved. Therefore, we believe that the concept of charge transfer offers a novel perspective for the preparation of high-performance assemblies.

Reinforced flexible solid-state electrolyte membrane by polyurethane polymer of intrinsic microporosity for high-energy-density lithium metal battery

Poly (ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) are restricted in commercial applications due to the low ionic conductivity at ambient temperature and fragile mechanical properties. Polyurethanes (PUs) are unique materials coupled with superior rigidity and flexibility. Herein, we designed a novel polyurethane polymer of intrinsic microporosity (PPU), which was incorporated with PEO-based polymer electrolyte to prepare composite polymer electrolyte (CPE). The physicochemical and electrochemical properties of CPE membranes were explored. The high ionic conductivity (1.82 × 10−3 S cm−1 at 50 °C) and superior interfacial stability with the lithium anode was obtained. Furthermore, the rate performances and the cycling properties of CPE in LiFePO4 (LFP) batteries were extensively studied. The CPE-15% PPU film showed the excellent electrochemical stability of 84.3% capacity retention after 890 cycles at 0.5 C and 82.4% capacity retention after 500 cycles at 1.0 C at 50 °C. Especially, the CPE matched with high-voltage LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode delivered long-term stable cycling performances. The novel polymer electrolyte acquired could open up a new horizon to achieve high stable lithium metal batteries.

NaSbF4 nanoparticles as solid-state electrolytes in sodium-iodine batteries: sodium ion transport via conversion reaction and shuttle effect retarded by fluoride

Na-I2 batteries have emerged as an appealing energy storage technology owing to high energy density and cost-effectiveness. However, the practical application of Na-I2 batteries faces the dissolution of iodide/polyiodide in the electrolyte during the charge/discharge process. Herein, we immobilize I2 by utilization of NaSbF4 (NSF)-based solid-state electrolyte (SSE). Impressively, the Na+ transport in NSF nanoparticles (NPs) is via the conversion reaction of NaSbF4 + NaF ↔ Na2SbF5, which is different from the acknowledged Na+ diffusion mechanism via vacancies in inorganic SSEs. To improve the interfacial compatibility, a composite polymer electrolyte (CPE) is fabricated based on NSF, poly (vinylidene fluoride - hexafuoro -propylene) (PVDF-HFP) and NaClO4, giving rise to stable Na stripping/plating in Na|Na symmetric cell. Especially, the quasi-solid-state Na|NSF CPE |I2 full cell shows an outstanding electrochemical behavior, which is associated with the partial reduction of ClO4− → Cl− and the stabilization of I+ by F− or Cl− in the charge/discharge process. The resultant I+-F- or I+-Cl- intermediate can promote the multi-electron transfer of 2I− → I2 → 2I+, leading to enhanced capacity and mitigated shuttle effect of iodide. Meanwhile, the formation of I+-F- in turn weakens the interaction of Na⋯F in NSF, which is beneficial for Na+ transport.

Coordination polymer-reinforced composite polymer electrolyte for all-solid-state Li-metal batteries

Composite polymer electrolytes (CPEs) have garnered significant interest due to their lightweight, flexible, and suitability for large-scale processing. However, current CPEs still face challenges such as unsatisfactory ionic conductivity (σ), low Li+ transference number (t+), and poor interfacial stability. This study presents the synthesis of a coordination polymer by coordinating Co2+ with terpyridine-end-capped polyethylene glycol (Co(tpy)-PEG). The resulting Co(tpy)-PEG-reinforced PEO-based CPE exhibits exceptional properties, including a high σ of 0.22 mS cm−1, large t+ of 0.75, and superior durability in both Li|Li (1400 h at 0.2 mA cm−2) and Li|LiFePO4 cells (70% capacity retention after 1000 cycles at 1C) at 60 °C, comparable to the best available CPEs. The incorporation of Co(tpy)-PEG filler plays a vital role in enhancing the σ by disrupting the PEO crystallinity and creating additional Li+ conducting pathways. Additionally, it can free Li+ to increase t+ through Lewis acid-base interactions between Co2+ and TFSI−/O atoms, as well as NO3− and Li+. Furthermore, Co(tpy)-PEG facilitates the formation of a stable multicomponent solid electrolyte interphase containing beneficial Li2Sx, LiF, and Li3N. This work introduces a promising strategy for designing and preparing multifunctional fillers capable of simultaneously reinforcing the σ, t+, and interfacial stability of CPEs.

Mof-derived ionic conductor enhancing the performance of polymer electrolyte for solid-state lithium batteries

The solid-state electrolyte is an important component of solid-state batteries and significantly influences the performance of batteries. However, pure solid-state polymer electrolyte has challenges such as low ionic conductivity, weak mechanical strength and poor ability to inhibit lithium dendrites. Therefore, a unique nano porous structural material based on a metal–organic framework (MOF) was proposed as a filler to enhance the polymer electrolyte, which is lithium ionic liquid (Li-IL) immersed into the MIL-125 framework to transform MIL-125 from an inert conductor to an efficient ionic conductor to obtain MIL-125-Li. MIL-125-Li not only has Lewis acid nature, but also provides a more definite and continuous transport pathway for the rapid migration of Li+. The composite polymer electrolytes (CPEs), containing 15 wt% of MIL-125-Li, exhibit an ionic conductivity of 3.9 × 10-4 S cm−1 at 28 °C. Furthermore, the CPEs demonstrate excellent interfacial stability with the lithium metal electrode, effectively inhibiting the growth of lithium dendrites. The assembled symmetric Li/PL-15 % MIL-125/Li battery can be stably cycled for more than 700 h at 0.1 mA cm−2 at 28 °C. Applying the composite polymer electrolyte to LiFePO4/Li batteries, the discharge specific capacity achieves ∼130 mAh g-l with a capacity retention rate of 83.9 % after cycling for 500 cycles at 0.5C. This simple modification method provides a novel design idea for all solid-state lithium batteries with excellent electrochemical performance.

Development of a Novel Composite Polymer Electrolyte Membrane for Application as a Separator in a Dual Chamber Microbial Fuel Cell

Development of a Novel Composite Polymer Electrolyte Membrane for Application as a Separator in a Dual Chamber Microbial Fuel Cell

Characterization of methylcellulose based composite polymer electrolytes reinforced with Reduced-Graphene oxide

This work reports the effect of reduced-graphene oxide (ReGO) on the conductivity and other properties of ammonium bromide (NH4Br) doped methylcellulose-based electrolytes. Hydrazine monohydrate, N2H2·H2O is used as the reducing agent in synthesising ReGO from graphene oxide (GO). Methylcellulose-NH4Br-ReGO based electrolytes are prepared using solution cast method. Fourier transform infrared (FTIR) analysis provides the evidence of interaction between the materials. Introduction of 0.3 wt% ReGO has maximized the conductivity of electrolyte up to (9.00 ± 0.38) × 10−4 S cm−1. From transport analysis, the conductivity is found to be influenced by the number density (n) and mobility (μ) of ion. Conductivity result is supported by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) analysis. Ionic transference number (tion) of the highest conducting electrolyte is found to be 0.94, thus confirming ions as the dominant charge carriers. The highest conducting electrolyte shows a potential stability up to 1.7 V.

Graphene Oxide Nanoribbon-Based Composite Gel Polymer Electrolytes: Enhancing Mechanical Strength and Ionic Conductivity for Long Cycling Lifetime of Flexible Zinc–Air Batteries

Graphene Oxide Nanoribbon-Based Composite Gel Polymer Electrolytes: Enhancing Mechanical Strength and Ionic Conductivity for Long Cycling Lifetime of Flexible Zinc–Air Batteries

NaSn2F5 nanocluster composed of nanoparticles with matched lattices induced by dislocations: Accelerated sodium-ion transport via in situ oxidation in solid-state sodium metal battery

Na metal batteries using inorganic solid-state electrolytes (SSEs) have attracted extensive attention due to their superior safety and high energy density. However, their development is plagued by the unclear structural/volumetric evolution of SSEs and the corresponding Na+ migration mechanisms. In this work, NaSn2F5 (NSF) clusters are composed of nanoparticles (NPs) with matched lattices induced by dislocations, which can mitigate the volume swelling/shrinkage of the NPs. NSF behaves like a single ion conductor with a high Na+ transference number (tNa+) of 0.79. Specially, the ionic conductivity (σ) of NSF is increased from 7.64 × 10-6 to 5.42 × 10-5 S cm−1 after partial irreversible oxidation of Sn2+ (0.118 Å) → Sn4+ (0.069 Å) with the shrunk ionic radius during the charge process, giving more spaces for Na+ migration. Furthermore, a poly(acrylonitrile)-NaSn2F5-NaPF6 composite polymer electrolyte (NSF CPE) was fabricated with a σ of 4.13 × 10-4 S cm−1 and a tNa+ of 0.60. The NSF CPE-based symmetric cell can operate over 3000 h due to the couplings between the different components in NSF CPE, which is beneficial for ion transfer and the construction of stable solid electrolyte interface. And the quasi-solid-state Na|NSF CPE|Na3V2(PO4)3 full cell displays excellent electrochemical performance.

Polycaprolactone-Li6PS5Cl composite polymer electrolytes for stable room temperature all-solid-state lithium batteries

Incorporating inorganic fillers into solid polymer electrolytes (SPEs) to construct composite polymer electrolytes (CPEs) serves as an effective strategy to comprehensively enhance the properties of solid electrolytes. Herein, a CPE is fabricated by integrating Li6PS5Cl particles into polycaprolactone (PCL). The addition of active fillers could effectively weaken the crystallization of polymer and increase the ionic conductivity of the solid electrolyte. In particular, the PCL-based polymer electrolyte with 3% Li6PS5Cl (PCL-3) exhibits an excellent ionic conductivity of 1.36×10−4 S cm−1 at room temperature, which is one order higher than that of PCL polymer solid electrolyte. And it achieves a high critical current density of 2.2 mA cm−2 with a capacity of 2.2 mAh cm−2. The assembled Li symmetric battery can cycle steadily for more than 3000 h at 0.5 mA cm−2 under room temperature. The LiFePO4/PCL-3/Li all-solid-state battery maintains a capacity of 125.3 mAh g−1 after 400 cycles at 0.2 C under room temperature. Notably, the LiFePO4//Li battery also shows stable cycling at 40 °C, exhibiting high reversible specific capacities of 156.7 mAh g−1 and 126.3 mAh g−1 with a retention rate of 97.15% and 94.6% at 0.2 C and 0.5 C after 100 cycles, respectively, showing promising application prospects for all-solid-state lithium metal batteries.

Vertically-Aligned Card-House Structure for Composite Solid Polymer Electrolyte with Fast and Stable Ion Transport Channels.

All-solid-state lithium batteries (ASSLBs) are highly promising as next-generation energy storage devices owing to their potential for great safety and high energy density. This work demonstrates that composite solid polymer electrolyte with vertically-aligned card-house structure can simultaneously improve the high rate and long-term cycling performance of ASSLBs. The vertical alignment of laponite nanosheets creates fast and uniform Li+ ion transport channels at the nanosheets/polymer interphase, resulting in high ionic conductivity of 8.9 × 10-4 S cm-1 and Li+ transference number of 0.32 at 60°C, as well as uniformly distributed solid electrolyte interphase. Such electrolyte is characterized by high mechanical strength, low flammability, excellent structural stability and stable ion transport channels. In addition, the ASSLB cell with the electrolyte and LiFePO4 cathode delivers a high discharge specific capacity of 124.8 mAh g-1, which accounts for 85.6% of its initial capacity after 500 cycles at 1C. The reasonable design through structural control strategy by interconnecting the vertically-aligned nanosheets open a way to fabricate high performance composite solid polymer electrolytes.

A gel polymer electrolyte based on IL@NH2-MIL-53 (Al) for high-performance all-solid-state lithium metal batteries

Solid polymer composite electrolytes possess the benefits of superior compatibility with electrodes and good thermal characteristics for more secure energy storage equipment. Herein, a new gel polymer electrolyte (GPE) containing NH2-MIL-53(Al), [PP13][TFSI], LiTFSI, and PVDF-HFP was prepared using a simple method of solution casting. The effects of encapsulating different ratios of ionic liquid ([PP13][TFSI]) into the micropores of functionalized metal-organic frameworks (NH2-MIL-53(Al)) on the electrochemical properties were compared. XRD, SEM, Nitrogen adsorption-desorption isotherms and electrochemical measurements were conducted. This GPE demonstrates a superior ionic conductivity of 8.08×10–4 S cm–1 at 60 °C and can sustain a discharge specific capacity of 156.6 mAh g–1 at 0.2 C for over 100 cycles. This work might offer a potential approach to alleviate the solid-solid contact with the solid-state electrolyte and electrodes, and broadens up new window for the creation of all-solid-state batteries.

Composite polymer electrolyte based on poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) for solid-state batteries

Using solid-state electrolytes (SSEs) with excellent thermal and electrical stability to replace liquid electrolytes, and assembling solid-state lithium-ion batteries (SSLIBs) is considered the best solution to these safety issues. However, it is difficult for a single electrolyte to have the characteristics of high ionic conductivity, low interface resistance, and high stability of the counter electrode at the same time. In this work, the composite polymer electrolyte membrane (CPE) of inorganic Li1.3Al0.3Ti1.7(PO4)3 (LATP) and organic poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) polymer was successfully prepared by traditional casting method. The addition of LATP (10 wt %) ceramic powder makes CPE membrane (CPE-10) exhibit excellent electrochemical performance: the lithium-ion transference number and electrochemical window are as high as 0.60 and 4.94 V, respectively. Moreover, the CPE-10 showed excellent Li-metal stability, thereby enabling the Li–Li symmetric cells to stably run for over 300 h at 0.1 mA/cm2 with effective lithium dendrite inhibition. When paired with a high-voltage LiNi0.6Co0.2Mn0.2O2 (NCM622) cathode, the Li/CPE-10/NCM622 cell exhibited excellent electrochemical performance: the highest specific discharge capacity of 152 mAh/g could be conducted at 0.2C after 50 cycles corresponding to 100% Coulombic efficiencies. The prepared CPE-10 demonstrates excellent electrochemical performance, providing an effective design strategy for SSLMBs.

PVDF-HFP Based, Quasi-Solid Nanocomposite Electrolytes for Lithium Metal Batteries.

Composite polymer electrolytes are systems of choice for future solid-state lithium metal batteries (LMBs). Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) is among the most interesting matrices to develop new generation quasi-solid electrolytes (QSEs). Here it is reported on nanocomposites made of PVDF-HFP and pegylated SiO2 nanoparticles. Silica-based hybrid nanofillers are obtained by grafting chains of poly(ethylene glycol) methyl ether (PEG) with different molecular weight on the surface of silica nanoparticles. The functionalized nanofiller improves the mechanical, transport and electrochemical properties of the QSEs, which show good ionic conductivity values and high resistance against dendrite penetration, ensuring boosted long and safe device operation. The most promising result is obtained by dispersing 5wt% of SiO2 functionalized with short PEG chains (PEG750, Mw = 750gmol-1) in the PVDF-HFP matrix with an ease solvent-casting procedure. It shows ionic conductivity of 0.1mScm-1 at 25°C, more than 250h resistance to stripping/plating, and impressive results during cycling tests in LMB with LiFePO4 cathode.

The intermolecular interaction enables ordered ion transport in quasi-solid-state electrolyte for ultra-long life lithium-metal battery

Composite gel polymer electrolytes (CGPEs) have received wide attention due to their great potential to improve the safety and cycling stability of lithium (Li) metal batteries. However, the poor interface compatibility between the filler and polymer in CGPEs severely hinders lithium-ion (Li+) pathways and limits cell performance. Herein, we propose an Al(EtO)3 nanowires framework that can trigger poly (ethylene glycol) diglycidyl ether (PEGDE) to undergo ring opening polymerization, thus inducing polymer tight combination on the surface of Al(EtO)3 nanowires framework and dividing the polymer matrix into mesh units, contributing to ordered Li+ transport and dendrite-free deposition on the metallic anode. Such a CGPE with highly conductive and interface compatibility facilitates a high-performance quasi-solid-state Li||Li cell with an excellent long-term cycling stability for over 3000 h without a short circuit and registers a high capacity of 146.9 mAh g−1 after 46 cycles at a mass loading of 6 mg cm−2. Solid-state nuclear magnetic technology clearly clarifies the transport path of lithium ions in Al(EtO)3-based gel polymer electrolyte (AGPE). The results open up a new way to improve the electrochemical performances of composite electrolyte and promote its commercial application process.

Incorporating LLTO ceramic into PVDF/PEO polymer electrolyte for lithium-ion capacitor

Hybrid supercapacitors are a prominent energy storage option for electric vehicles because they have high power and energy densities. Electrolyte plays a major role in hybrid supercapacitor performance. Our report is on a ceramic composite polymer electrolyte made from poly (vinylidene fluoride) (PVDF)/poly (ethylene oxide) (PEO)/ Lithium Lanthanum titanate (LLTO), which we analyzed for its structure, thermal behavior, and electrical characteristics. The different weight percentages (10 wt%, 20 wt%, 30 wt% and 40 wt%) of LLTO were incorporated into the PVDF/PEO polymer blends to study the performance of the electrolyte by FTIR, microscopic analysis, TGA, and impedance spectroscopy. Based on the results, 40 wt% of LLTO containing CPE showed high liquid electrolyte uptake behaviour (275 %) and a high ionic conductivity value (3.94 mS/cm). In addition, incorporating LLTO affects the PVDF/PEO polymer backbone and enhances the amorphicity of polymer blends. This result enhances the polymer segmental motion and reduces the relaxation time. We fabricated hybrid supercapacitor coin cells using 10 wt% and 40 wt% of LLTO containing composite polymer electrolyte and tested them. The 40 wt% LLTO-containing CPE-based hybrid supercapacitor possesses a high specific capacitance value (182F/g) and a long cycle life (upto10000 cycles).