Solid-state Polymer Batteries Research Articles

Solid-State Polymer Battery: Manufacturing Process and Characterization

Solid-state batteries are a promising technology that could provide higher energy density, better safety, longer cycle life and a wider operating temperature range than current commercial LiBs [1] .The solid electrolyte is the main component of all-solid-state batteries. It can be ceramic, glass, polymer, or a mixture. Solid Polymer Electrolyte (SPEs) have received distinctive attention, especially by industry, owing to their potential advantages such as safety, lightweight, high flexibility, and realistic processability. However, despite fast growing interest in solid-state technology, reports on the scalable production of all-solid-state lithium-ion batteries using electrodes with meaningful areal capacities are rather scarce [2] . Moreover, chemical, and mechanical challenges remain. The intimate contact between the electrode and the solid electrolyte is difficult due its non-infiltrative nature. This lack of intimate contact severely limits the cycling properties [3] . The development of effective strategies to alleviate the issue of physical contact is imperative in the engineering of solid-state batteries [4] .In the frame of SAFELiMOVE (Advanced all Solid stAte saFE Lithium Metal technology tOwards Vehicle Electrification) project, we assemble a solid-state pouch based on lithium metal anode, a solid polymer electrolyte layer and a compatible cathode. In work, we report on a reliable fabrication process of large-scale all-solid-state lithium-ion batteries using cathodes prepared by CIDETEC, lithium anode provided by Hydro-Quebec, polymers provided by CICe, inorganic filler provided by SCHOTT and a solid polymer electrolyte manufactured at SAFT.All-solid-state lithium-ion battery pouch cells have been successfully built with consistent electrochemical performance. Cycling that shows the good performance of those cells and the lesson learned regarding their cycling conditions will be presented. [1] J. Motalli, “A solid future Nature, 526, S96 (2015) [2] Ningxin Zhang et al “Scalable preparation of practical 1Ah all-solid-state lithium-ion batteries cells and their abuse tests”, Journal of Energy Storage 59 (2023) 106547 [3] Li et al.“Atomically Intimate Contact between Solid Electrolytes and Electrodes for Li Batteries” Mater 1, 1001-1016, October 2, 2019. [4] Theodosios Famprikis, Pieremanuele Canepa, James A. Dawson, M. Saiful Islam and Christian Masquelier“Fundamentals of inorganic solid-state electrolytes for batteries” Nature Materials-August 2019. Figure 1

Electrochemical Passivation of Aluminum As a Current Collector for Solid-State Polymer Batteries : PEO/LiTFSI Polymer Electrolyte

Investigation of the electrochemical properties and passivation mechanism of aluminum as a current collector for solid-state polymer batteries is carried out. Herein, electrochemical stabilities of Polyethylene glycol (PEO) based solid-state electrolyte containing Lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) salt are proved using electrochemical dynamic- and transient-mode polarization with surface scratching. These results indicate that Al metal undergoes passivation with a layer below 4.5 V vs. Li+/Li. And then Time-of-flight secondary ion mass spectroscopy (ToF-SIMS) and X-ray photoelectron spectroscopy (XPS) reveal double layers are formed during the passivation on Al metal surface, with the outer layer composed of metal fluorides (AlF3) and the inner layer composed of metal oxides (Al2O3). The formation of the AlF3 layer on Al metal surface is attributed to the reaction between Al2O3 and HF following as Al2O3 + 6HF → 2AlF3 + 3H2O. Therefore, successful passivation achieved by the formation of AlF3 on the Al2O3 surface of Al metal facilitates to be widely used as a current collector for lithium metal polymer batteries. Therefore, successful passivation by the formation of AlF3 on the Al2O3 surface of Al metal making it a promising choice for the positive electrode in lithium metal polymer batteries.

Origin of rate limitations in solid-state polymer batteries from constrained segmental dynamics within the cathode

Origin of rate limitations in solid-state polymer batteries from constrained segmental dynamics within the cathode

The interphasial degradation of 4.2 V-class poly(ethylene oxide)-based solid batteries beyond electrochemical voltage limit

Solid-state polymer electrolytes (SPEs) have attracted increasing attention due to good interfacial contact, light weight, and easy manufacturing. However, the practical application of SPEs such as the most widely studied poly(ethylene oxide) (PEO) in high-energy solid polymer batteries is still challenging, and the reasons are yet elusive. Here, it is found that the mismatch between PEO and 4.2 V-class cathodes is beyond the limited electrochemical window of PEO in the solid LiNi1/3Mn1/3Co1/3O2 (NMC)-PEO batteries. The initial oxidation of PEO initiates remarkable surface reconstruction of NMC grains in solid batteries that are different from the situation in liquid electrolytes. Well-aligned nanovoids are observed in NMC grains during the diffusion of surface reconstruction layers towards the bulk in solid batteries. The substantial interphasial degradation, therefore, blocks smooth Li+ transport across the NMC-PEO interface and causes performance degradation. A thin yet effective LiF-containing protection layer on NMC can effectively stabilize the NMC-PEO interface with a greatly improved lifespan of NMC|PEO|Li batteries. This work deepens the understanding of degradations in high-voltage solid-state polymer batteries.

Ion transport property studies of a new TiO2 dispersed Na+ ion conducting nanocomposite polymer electrolytes

Ion transport property studies of a new Na+ ion conducting nanocomposite polymer electrolytes (NCPEs): (1-x) [75PEO:25NaPO3] + x TiO2 where 0 ≤ x ≤ 18 wt%, are reported. The present NCPEs films have been casted using a recently developed hot-press method. The maximum ionic conductivity (σ ∼ 2.3 × 10-5 S.cm−1) have been obtained at the composition: [95(75PEO:25NaPO3) + 5 TiO2] and this has been referred to as optimum conducting composition (OCC). Ion transport properties have been explained with the help of some basic ionic parameters viz. ionic conductivity (σ), ionic mobility (μ), mobile ion concentration (n) and ionic transference number (tion). To compute the activation energy (Ea) values of different samples, temperature dependent ionic conductivity studies have been done. Solid state polymer battery was fabricated using the NCPE OCC as an electrolyte and studied their cell performances.

Sodium-ion-conducting solid polymer electrolyte: temperature-dependent ionic parameters and solid-state polymer battery fabrication

Temperature-dependent ionic parameters and solid-state polymer battery studies of a newly synthesized sodium-ion-conducting solid polymer electrolytes (SPEs): (1 − x) PEO: x NaCl, where 0 ≤ x ≤ 50 in wt%, are reported. The present SPEs are synthesized by a recently developed hot-press/dry technique in place of traditional solution-cast method. The room temperature conductivity (σ) of the optimum conducting composition (OCC), i.e., (70PEO:30NaCl) is ~ 4.5 × 10–6 Scm−1. The ion transport behavior has been explained with the help of some basic ionic parameters viz. ionic conductivity (σ), ionic mobility (μ), mobile ion concentration (n), ionic transference number (tion) and ionic drift velocity (vd) by using various experimental as well as theoretical models. The conductivity enhancement and polymer–salt complexations have been confirmed by X-ray diffraction, differential scanning calorimetric and thermogravimetric analysis. A new solid-state polymer battery is also fabricated by using the optimum conducting composition of solid polymer electrolyte (SPE OCC) as an electrolyte, and their cell parameters have been calculated at room temperature.

Designing electrolytes with polymerlike glass-forming properties and fast ion transport at low temperatures

In the presence of Lewis acid salts, the cyclic ether, dioxolane (DOL), is known to undergo ring-opening polymerization inside electrochemical cells to form solid-state polymer batteries with good interfacial charge-transport properties. Here we report that LiNO3, which is unable to ring-open DOL, possesses a previously unknown ability to coordinate with and strain DOL molecules in bulk liquids, completely arresting their crystallization. The strained DOL electrolytes exhibit physical properties analogous to amorphous polymers, including a prominent glass transition, elevated moduli, and low activation entropy for ion transport, but manifest unusually high, liquidlike ionic conductivities (e.g., 1 mS/cm) at temperatures as low as -50 °C. Systematic electrochemical studies reveal that the electrolytes also promote reversible cycling of Li metal anodes with high Coulombic efficiency (CE) on both conventional planar substrates (1 mAh/cm2 over 1,000 cycles with 99.1% CE; 3 mAh/cm2 over 300 cycles with 99.2% CE) and unconventional, nonplanar/three-dimensional (3D) substrates (10 mAh/cm2 over 100 cycles with 99.3% CE). Our finding that LiNO3 promotes reversibility of Li metal electrodes in liquid DOL electrolytes by a physical mechanism provides a possible solution to a long-standing puzzle in the field about the versatility of LiNO3 salt additives for enhancing reversibility of Li metal electrodes in essentially any aprotic liquid electrolyte solvent. As a first step toward understanding practical benefits of these findings, we create functional Li||lithium iron phosphate (LFP) batteries in which LFP cathodes with high capacity (5 to 10 mAh/cm2) are paired with thin (50 μm) lithium metal anodes, and investigate their galvanostatic electrochemical cycling behaviors.

(Invited) Understanding Chemical, Mechanical and Thermal Stability of NCA in Polymer Solid-State Batteries

The structural integrity and chemical stability of layered Ni-rich oxide cathode materials are influential factors that critically affect the performance and reliability of lithium batteries. Prolonged battery operation often involves repeated phase transitions, buildup of mechanical stresses, which could result in chemical and mechanical changes in cathodes. Chemo-thermo-mechanical interplay can cause performance degradation through various processes. Here we systematically investigate such complex chemomechanical and chemothermal interplays over a wide range of length scales within the hierarchically structured polymer solid-state batteries. This presentation will discuss our understanding of 1) The formation of mesoscale cracks and corresponding state of charge (SOC) inhomogeneity within secondary NCA particle cycled in solid polymer batteries1 2) Thermal decomposition, fracture (intergranular and intragranular), and mesopores formation due to oxygen evolution in delithiated Li0.30NCA particles upon heating2 3) long-term chemothermal stability of delithiated Li0.30NCA at relevant operating conditions of polymer solid-state batteries.3 Our investigation provides a fundamental understanding of chemo-thermo-mechanical breakdown of the NCA in solid-state polymer batteries.Reference : 1. Besli, M. M. et al. Mesoscale Chemomechanical Interplay of the LiNi0.8Co0.15Al0.05O2 Cathode in Solid-State Polymer Batteries. Chem. Mater. 31, 491–501 (2019).2. Besli, M. M. et al. Thermally-driven mesopore formation and oxygen release in delithiated NCA cathode particles. J. Mater. Chem. A 7, 12593–12603 (2019).3. Besli, M. M. et al. Long-Term Chemothermal Stability of Delithiated NCA in Polymer Solid-State Batteries. J. Mater. Chem. A 11–13 (2019) doi:10.1039/c9ta11103d.

Dendrite-free lithium metal solid battery with a novel polyester based triblock copolymer solid-state electrolyte

Abstract Solid-state polymer Li metal batteries have been regarded as a promising candidate for next-generation batteries due to their high-energy densities provided by the Li metal and the improved safety provided by the solid electrolyte. Polyester is one attractive polymer host, which could be an alternative to polyether-based solid electrolyte due to its excellent lithium ion transport ability and wide electrochemical stability window. Here, a BAB-type triblock copolymer is synthesized with poly (propylene carbonate) as A-block and poly (e-caprolactone) as B-block. The triblock copolymer electrolyte exhibits a high ionic conductivity of 3 × 10−5 S cm−1 at 30 °C with a high lithium ion transference number (0.4) and an extremely wide electrochemical window (5 V). A highly stable interface against Li metal is maintained for more than 760 h at a current density of 0.1 mA cm−2. A LiFePO4 cathode based solid state battery delivers a high discharge capacity of 142 mA h g−1 at 0.05C, room temperature, and 161 mA h g−1 at 0.1C, 70 °C with a capacity retention of 90% after 200 cycles. To understand the excellent electrochemical performance, the morphology and chemical information at both anode and cathode interface are characterized and analyzed. The synthesis of this triblock copolymer demonstrates a new direction in developing high ionic conductivity solid polymer electrolyte for solid-state polymer batteries.

Bio-host pectin complexed with dilithium borate based solid electrolytes for polymer batteries

Solid state polymer batteries have become the center of focus to fulfill the goal towards the accomplishment of storage systems with high power and energy densities in affordable cost and safety. In this connection, a new Solid Biopolymer Electrolyte (SBE) membrane, pectin complexed with dilithium borate, was prepared using solution casting technique and investigated by XRD, AC impedance and LSV techniques. The ion conductivity to a maximum of 1.69 × 10−5 Scm−1 for 60 (M.wt%) pectin: 40 (M.wt%) Li2B4O7 composition was attributed to the addition of Li2B4O7, which increases the number of conducting ion species. Increase in conductivity with temperature can be correlated with the free volume model. The lowest value of activation energy and an electrochemical stability window of 3.11 V were obtained for the highest ion conducting sample, indicating that this composition is a promising biopolymer membrane electrolyte in all solid state batteries.

Poly(ionic liquid)‐Based Hybrid Hierarchical Free‐Standing Electrolytes with Enhanced Ion Transport and Fire Retardancy Towards Long‐Cycle‐Life and Safe Lithium Batteries

AbstractIonic liquid electrolytes (ILEs), owing to their wide electrochemical window, high ionic conductivity, and low volatility, have been extensively applied in the field of energy storage devices. However, it is extremely significant and greatly challenging to seek the counterbalance of good mechanical properties and excellent electrochemical performances, including a high transference number of ILEs for safe flexible lithium batteries. In this work, a novel hybrid poly(ionic liquid)‐based quasi‐solid electrolyte containing silica nanoparticles (SiO2‐PIL‐QSE) is fabricated through the one‐step in situ polymerization of the ionic liquid covalently tethered to silica nanoparticles (SiO2‐IL‐TFSI), which fills a poly(vinylidene fluoride‐hexafluoropropylene) (PVdF‐HFP) porous membrane prepared through phase inversion. The hybrid hierarchical porous architecture endows the SiO2‐PIL‐QSE with excellent thermal stability, good fire safety (i. e. nonflammable and low shrinkage), improved mechanical strength, and excellent electrochemical performance, including a high room‐temperature ionic conductivity of 1.69 mS cm−1, a superior electrochemical window up to 5.5 V, as well as a high lithium‐ion transference of 0.46. Accordingly, the LiFePO4|SiO2‐PIL‐QSE|Li cell can maintain a discharge specific capacity of 133.7 mAh g−1 at 0.1 C at 25 °C with a capacity retention ratio of 91.9 % after 400 cycles. The excellent performances and good applicability in the pouch‐type battery of SiO2‐PIL‐QSE indicate a good prospect in the field of flexible solid‐state polymer batteries (SSPB).

Preparation and dielectric properties of PVP-based polymer electrolyte films for solid-state battery application

Solid polymer electrolyte has been prepared with the combination of PVP (poly vinyl pyrrolidone) and magnesium sulfate heptahydrate (MgSO4·7H2O) by solution cast technique and subsequently characterized for possible polymer battery application. Structural studies were carried out by XRD technique. DSC analysis revealed that the micro-porous polymer membrane is thermally stable up to 300 °C. The surface morphology of the films was analyzed by SEM. Electrical conductivity was performed using AC impedance analyzing technique in the frequency range from 4 kHz to 5 MHz. Complex impedance spectroscopy revealed that the enhancement in electrical conductivity by salt doping and the conductivity maximum was obtained for 15 wt% of MgSO4·7H2O salt concentration. Optical absorption studies were carried out on to the prepared films in the wavelength range 200–600 nm. Solid-state polymer battery has been fabricated with the configuration of Mg+/(PVP + MgSO4·7H2O)/(I2 + C + electrolyte) and discharge characteristics were studied for a constant load of 100 kΩ. The cell parameters like open-circuit voltage, short circuit current, energy density and power density were calculated.

Hot pressed K+ ion conducting solid polymer electrolytes: synthesis, ion conduction and polymeric battery fabrication

Synthesis and ion transport studies of hot pressed K+ ion conducting solid polymer electrolytes (SPEs): (1 − x) PEO:x KBr, where 0 < x < 50 in wt%, are reported. The solvent-free/hot-press method is used for synthesis of the present SPEs. The two orders of conductivity enhancement achieved after the polymer-salt complexation in SPE composition: (70:30) with conductivity (σ) ~ 5.01 × 10−7 S cm−1 from the room temperature conductivity measurements. Materials characterization and polymer-salt complexations of present SPEs have been explained with the help of various techniques viz. X-ray diffraction, Fourier transform infrared, differential scanning calorimetry, thermogravimetric analysis, scanning electron microscopy technique. To explain the ion conduction in the present SPEs, temperature dependent ionic conductivity (σ), ionic mobility (μ), mobile ion concentration (n), ionic transference number (t ion ) and ionic drift velocity (v d ) have been calculated with the help of various experimental techniques. A solid state polymer battery is also fabricated by using the present SPE as an electrolyte and have been calculated their important cell parameters at room temperature.

Synthesis, characterization and polymer battery fabrication of hot-pressed ion conducting nano-composite polymer electrolytes

Synthesis and characterization of hot-pressed ion conducting nano-composite polymer electrolytes or polymer–matrix composites (NCPEs/PMCs):(1−x)[80PEO:20KI]:xSiO2 where 0<x<14wt.%, are reported. NCPEs were cast using a recently developed hot-press method in place of traditional solution-cast/sol–gel technique. Two and half orders of conductivity enhancement were found in NCPEs after the dispersion of nano-sized SiO2 inert material in the polymeric host, from the room temperature conductivity measurement. The polymer–salt/nano-filler SiO2 complexation, surface analysis and thermal properties characterization were done with the help of XRD, SEM, DSC and TGA studies. The ionic conductivity (σ) enhancements were explained using various experimental results viz. ionic mobility (μ), mobile ion concentration (n) values and various theoretical models. The ionic transference number (tion) of optimum conducting composition of NCPE was also determined with the help of Transient Ionic Current (TIC) technique. To compute the activation energy (Ea) in NCPEs, the temperature dependent conductivity studies were done and Ea values were determined by using logσ–1/T Arrhenius plots. A solid state polymer battery was fabricated using the NCPE OCC as an electrolyte and cell-potential discharge characteristic studies were also reported with different load conditions at room temperature.

Synthesis, characterization and device application of hot-pressed solid polymer electrolytes:(1 − x) PEO:x NaHCO3

Synthesis and io n transport characterization of hot-pressed solid polymer electrolyte (SPE) membranes:(1 − x) poly (ethylene oxide) (PEO):x NaHCO3, where 0 < x < 50 wt.%, have been reported. SPE films have been synthesized using a hot-press technique in place of the traditional solution-cast method. A conductivity enhancement of the two orders of magnitude was achieved in SPE film:70PEO:30NaHCO3 and this composition has been referred to as optimum conducting composition (OCC). Materials characterization was done with the help of XRD, SEM, FTIR, DSC and TGA techniques. The ion transport behavior in SPE membranes has been discussed on the basis of experimental measurements on their ionic conductivity (σ), ionic mobility (μ) and some other important parameters. A solid-state polymer battery was fabricated using SPE OCC at room temperature, as a device application.

The factors affecting the electrochemical performance of Li/Li xMnO 2 solid-state polymer battery

The electrochemical behavior of an all solid-state Li/Li x MnO 2 polymer cell was evaluated by using three kinds of polymer-electrolytes in the composite positive electrodes. The discharge-rate capability and cycle life was significantly improved by using low-molecular weight polymer-electrolyte. It was confirmed that the improvement is due to the smaller charge transfer resistance between a polymer-electrolyte/cathode material interface, and the compatibility of polymer-electrolyte toward the cathode material is much more direct than the ionic conductivity of the polymer-electrolyte in the effects on its rate capability and cyclability.

Polymeric Nanoscale All-Solid State Battery

AbstractThe advent of polymer electrolytes has provided a promising route to an all solid-state polymer battery. Such a battery would have greater safety, without potential discharge of liquid or gel electrolyte. Current battery configurations typically involve a metal anode, a solvent-plasticized polyelectrolyte, such as poly (ethylene oxide) (PEO), and a composite cathode. We have synthesized an A/B/C triblock copolymer which could have potential use as an all-solid state nanoscale polymer lithium battery. The polymeric battery was synthesized with an anode, electrolyte and cathode by synthesizing an A/B/C triblock copolymer whose microphase separation would form lamellar domains. These nanodomains contain cobalt oxide, a derivative of PEO synthesized by ring opening metathesis polymerization, and a spinel phase LiMn2O4 as the anode, electrolyte and cathode material, respectively. The first block contains cobalt oxide that stores lithium ion in a novel electrochemical reaction that allows use in a battery configuration. The second block is polyethylene oxide derived from an unsaturated crown ether, and is used for its high ionic conductivity. The third block contains LiMn2O4, which is currently being investigated as a potential cathode material because of its low toxicity and ease of preparation. The nanometer size domains in the battery can be used in unique applications in microelectronics. In addition, such size scale allows use of the battery in discrete circuits, reducing the amount of wiring necessary in conventional battery configurations.

Electroactive polymer blends

AbstractThe rapid development of two new classes of electrically active polymer materials, electronically conducting and electroactive polymers and ion‐conducting polymers respectively, offers new possibilities for application of both classes of material, especially in combination with each other. While some of these combinations have been attempted before, they all met serious problems due to poor interpenetration of the two polymers. The recent availability of solubilized and soluble electroactive and conductive polymers has greatly advanced the possibilities of reducing the interpenetration problem. Some experimental studies using the combination of solubilized electroactive polypyrrole with poly(ethylene oxide) in an electroactive polymer blend electrode for solid‐state polymer batteries are discussed. The opportunities for using polymer blends for solid‐state electrochemical polymeric devices, and avenues for the development of materials for such devices, are also reviewed.