Polymer electrolytes exhibit marked decreases in ionic conductivity as temperatures drop below 0°C, with typical conductivity values falling from 10-3 S/cm at room temperature to below 10-5 S/cm at -20°C. This performance degradation stems from reduced polymer chain mobility and restricted ion transport mechanisms, creating significant barriers for electric vehicle operation in cold climates where battery performance can decrease by up to 40%.

The fundamental challenge lies in maintaining sufficient ionic mobility through polymer matrices while preserving the mechanical stability and interfacial contact required for practical solid-state battery applications.

This page brings together solutions from recent research—including composite sulfide-based electrolytes with integrated lithium salts, polymer matrices incorporating ionic plastic crystals, polyionic liquid electrolytes with long-chain heterocyclic structures, and semi-interpenetrating networks with specialized cross-linking agents. These and other approaches demonstrate how materials engineering can address the critical temperature-dependence of ion transport while maintaining the safety advantages of solid-state systems.

1. Composite Sulfide-Based Electrolyte with Integrated Lithium Salts for All-Solid-State Lithium-Ion Batteries

GTC-POWER NEW ENERGY TECHNOLOGY CO LTD, 2024

A composite electrolyte for all-solid-state lithium-ion batteries that improves charge and discharge efficiency through a novel sulfide-based electrolyte system. The electrolyte combines a lithium salt with a sulfide electrolyte, where the sulfide electrolyte contains lithium salts such as LiTFSI, LiFSI, and Li(CF3sO2)3C. This composition enhances the electrolyte's ionic conductivity while maintaining the sulfide's thermal stability and solid-state characteristics. The electrolyte's performance is demonstrated through comprehensive testing, including high-pressure testing and extensive cycle testing.

2. Coated Binder Material with Ionic Plastic Crystal and Lithium Salt for Enhanced Lithium Conductivity in Solid-State Batteries

GAONENG SHIDAI SHENZHEN NEW ENERGY TECH CO LTD, 2024

Coated binder material for solid-state batteries that improves performance by increasing lithium conductivity inside the battery. The coated binder has an ionic plastic crystal and lithium salt coated on its surface. This provides lithium conduction pathways in the battery beyond just the binder's binding function. The coated binder is prepared by wet coating techniques where the ionic crystal and lithium salt dissolve in solvent while the binder remains insoluble. After evaporating the solvent, the coated ionic crystal and lithium salt precipitate on the binder surface. This creates a coated binder with lithium conduction beyond the binder's binding function, reducing interface impedance in the battery.

3. Composite Solid Electrolyte with Polymer Matrix and Zinc Phosphate Phase for Sodium Batteries

ZHEJIANG HUANGNENG NEW ENERGY TECHNOLOGY CO LTD, 2023

Sodium battery composite solid electrolyte for all-solid-state batteries that addresses the limitations of conventional polymer-based electrolytes. The electrolyte combines a polymer matrix with an inorganic phase, specifically zinc phosphate, which enhances ionic conductivity while maintaining mechanical integrity. The zinc phosphate phase prevents dendrite growth and improves interface compatibility, while the polymer matrix maintains flexibility and conductivity. The composite electrolyte achieves high ionic conductivity, improved mechanical properties, and enhanced safety performance compared to conventional polymer-based electrolytes.

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4. Solid-State Battery Cell with Alternating Copolymer Electrolyte and Composite Electrode Structure

GAC AION NEW ENERGY AUTOMOBILE CO LTD, 2023

Solid-state battery cell comprising an all-solid-state battery with a solid electrolyte, positive and negative electrodes, and a current collector, wherein the solid electrolyte is made from an alternating copolymer and its preparation method, and the positive and negative electrodes are made from a current collector material and their preparation method. The solid electrolyte contains a polymer electrolyte that exhibits conductivity close to that of liquid electrolytes at room temperature, while the positive and negative electrodes contain active materials, conductive agents, and binders.

5. Composite Electrolyte Membrane with Organic Ion Plastic Crystal Doped Coating and Base Film

JILIN DONGCHI NEW ENERGY TECHNOLOGY CO LTD, 2022

Organic ion plastic crystal doped composite electrolyte membrane for lithium-ion batteries, comprising an organic ion plastic crystal doped composite electrolyte coating and a base film. The membrane combines the advantages of inorganic solid-state electrolytes and polymer solid-state electrolytes, with high ionic conductivity, chemical stability, and electrical properties. The coating is prepared through a combination of ultrasonic dispersion and magnetic stirring, with specific formulations of lithium salts and inorganic particles. The resulting membrane exhibits excellent interface stability between electrolyte and electrode, with no obvious lithium dendrites on the surface of lithium metal negative electrode after cycle charge and discharge.

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6. Solid-State Lithium Battery with Lithium Salt-Based Electrolyte Interface Layer Incorporating Ion-Conducting Plastic Crystal and Polymer Matrix

NISSAN MOTOR CO LTD, 2022

Solid-state lithium battery with enhanced safety features through the incorporation of a lithium salt-based electrolyte interface layer. The layer, comprising an ion-conducting plastic crystal, a lithium salt, and a polymer matrix, prevents electrodeposition of metallic lithium during charging by forming a solid electrolyte interface. This interface layer protects against internal short circuits while maintaining high energy density. The lithium salt-based electrolyte enables stable lithium ion transport in the solid electrolyte, while the plastic crystal maintains its ionic conductivity.

7. Polymer Electrolyte with Ammonium-Based Matrix and Ionic Liquid Integration

HYUNDAI MOTOR CO LTD, 2022

Polymer electrolyte with enhanced ionic conductivity and mechanical properties, achieved through a novel polymer matrix composition. The electrolyte comprises a polymer matrix with an ammonium-based repeating unit and an ionic liquid, where the polymer matrix contains a specific weight fraction of the ionic liquid. The polymer matrix maintains superior mechanical strength despite a low glass transition temperature, while maintaining high ionic conductivity and stability. The electrolyte's ionic conductivity reaches up to 2.60 mS/cm, with metal salt content ranging from 40% to 60%.

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8. Solid-State Battery Electrode with Polyionic Liquid-Based Solid Electrolyte and In-Situ Polymerized Copolymer Coating

SUZHOU NANOTECHNOLOGY AND NANO BIONIC RES INSTITUTE OF CHINESE ACADEMY OF SCIENCES, 2022

Solid-state battery electrode with enhanced ion transport and interface properties. The electrode comprises active material particles, conductive additives, a uniform and dense polyionic liquid-based solid electrolyte, and a current collector. The solid electrolyte is produced through in-situ polymerization of an ionic liquid monomer with a polymer monomer having reactive active groups. The resulting copolymer electrolyte is uniformly coated on the surface of active material particles, enabling efficient ion conduction between particles while improving interface contact.

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9. Polymer Electrolyte Lithium Battery with [BMIM]BF4, PC, and FEC Blend

CHINA NAT CHEMICAL SOUTH CONSTRUCTION INVESTMENT CO LTD, 2022

Polymer electrolyte lithium battery with enhanced safety and efficiency, comprising a polymer electrolyte prepared by blending [BMIM]BF4 with PC and FEC. The electrolyte achieves high ionic conductivity and non-flammability through synergistic effects of these components, enabling safe and efficient lithium-ion battery applications.

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10. Polymeric Gel with Ionic Liquid Grafted Natural Polymer for Enhanced Ionic Conductivity

UNIV NOVA DE LISBOA, 2021

Ionic conduction material in the form of a polymeric gel, its production process and application in electrochemical devices for energy applications. The material comprises a natural polymer grafted with an ionic liquid (IL) precursor, which undergoes immediate gelation upon dissolution. This IL-grafted polymer exhibits high ionic conductivity compared to conventional polymeric gels, with conductivity values up to 10 S/m, making it suitable for energy storage applications.

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11. Imidazole-Based Polyionic Liquid Electrolyte with Flexible Acrylate Copolymer Chains and Self-Repairing Acrylic Ester Monomers

MINERALS APPLICATION RESERCH INSTITUTE OF GUANGDONG PROVINCE, 2020

Imidazole-based polyionic liquid electrolyte with enhanced ionic conductivity and self-repair properties for lithium-ion batteries. The electrolyte comprises imidazole-based copolymer chains with flexible acrylate groups, combined with lithium salts and additives. The acrylate groups enable controlled chain flexibility, while the imidazole backbone provides ionic conductivity. The lithium salt mixture ensures reliable ionic conductivity while maintaining the electrolyte's thermal stability. The electrolyte's self-repair capabilities are achieved through a novel copolymerization process that incorporates acrylic ester monomers. This approach enables the electrolyte to maintain its ionic conductivity and mechanical properties even at elevated temperatures, making it suitable for lithium-ion battery applications.

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12. Composite Solid Electrolyte with In-Situ Polymerized Organic-Inorganic-Ionic Liquid Structure

SUZHOU INST NANO TECH & NANO BIONICS CAS, 2020

Organic-inorganic-ionic liquid composite solid electrolyte for lithium-ion batteries and supercapacitors, prepared through in-situ polymerization of an organic-inorganic-ionic liquid. The composite solid electrolyte combines a polymer backbone with inorganic nanoparticles, uniformly dispersed within the polymer matrix. This novel approach addresses the limitations of traditional polymer electrolytes by achieving high ionic conductivity, low interface impedance, and improved mechanical properties through the controlled incorporation of inorganic particles. The resulting composite electrolyte exhibits enhanced thermal stability, flame retardancy, and cycle stability, making it suitable for solid-state lithium metal batteries and other applications requiring high-performance solid-state electrolytes.

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13. Ionic Liquid Polymer with Perfluorosulfonamide Anion and Micro-Liquid Phase Structure for Enhanced Ion Conductivity and Mobility

BYD Company Limited, BYD COMPANY LTD, 2020

Ionic liquid polymer for lithium-ion batteries with improved conductivity and migration characteristics. The polymer contains a perfluorosulfonamide anion with weak coordination, which enables enhanced conductivity and lithium ion mobility compared to conventional anions. The polymer structure enables a micro-liquid phase that facilitates efficient ion migration, while maintaining the anion's stability and preventing aggregation. The polymer solid electrolyte can be prepared through polymerization of the ionic liquid monomer, offering a unique combination of conductivity, stability, and migration characteristics that address the challenges of traditional lithium-ion electrolytes.

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14. Polymer Layer Comprising Alkenyl-Functionalized Ionic Liquid Monomer and Lithium Salt for Solid-State Lithium Battery Interface Stability

SAIC MOTOR CORPORATION LTD, 2020

A modified layer for solid-state lithium batteries that improves interface stability and ionic conductivity between the electrode and electrolyte. The layer comprises a polymer formed by alkenyl-functionalized ionic liquid monomer, lithium salt, and photoinitiator, with specific mass ratios optimized for enhanced conductivity and interface compatibility. The layer is applied between the electrode and electrolyte, providing a uniform interface that enhances charge transfer and reduces interface impedance.

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15. Ionic Liquid Polymer with Hydrolysis-Induced Polymerization for Solid Electrolytes

比亚迪股份有限公司, BYD COMPANY LTD, 2019

Ionic liquid polymer and solid electrolyte containing the polymer, for use in lithium-ion batteries, particularly in solid-state batteries and fuel cells. The polymer contains a structure represented by formula (I), and the solid electrolyte contains the polymer. The polymer polymerizes through a hydrolysis reaction to form an ionic liquid, and the solid electrolyte contains the polymer as a solid electrolyte.

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16. All-Solid-State Lithium-Ion Battery with Cross-Linked Copolymer Electrolyte Matrix

BYD COMPANY LTD, 2019

All-solid-state lithium-ion battery with enhanced performance through cross-linked polymer electrolyte. The battery features a solid-state electrolyte comprising a cross-linked copolymer matrix with lithium salt dispersed within it. This matrix structure enables improved ionic conductivity and mechanical strength compared to conventional liquid electrolytes. The cross-linked structure prevents electrode-electrolyte interface impedance while facilitating efficient lithium ion transport between polymer segments. The battery design achieves high safety through the solid-state electrolyte, which prevents lithium metal contact between electrodes.

17. Polyionic Liquid Solid Electrolyte via Cross-Linking Polymerization of Ionic Liquid Monomers in Polymer Matrices

UNIV XI AN JIAOTONG, 2019

Preparation of polyionic liquid solid electrolyte through cross-linking polymerization of ionic liquid monomers in polymer matrices. The method involves polymerizing ionic liquid monomers in polymer matrices containing lithium salts, followed by cross-linking with a polymer matrix material like polyethylene oxide. The cross-linking process enables uniform solid electrolyte preparation while maintaining compatibility with lithium salts.

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18. Composite Solid Polymer Electrolyte Membrane with Nano-Ceramic Particles and Imidazole-Based Ionic Liquids

XIAN JIAOTONG UNIVERSITY, 2019

A composite solid polymer electrolyte membrane for lithium-ion batteries that addresses the limitations of traditional solid electrolytes. The membrane combines a polymer matrix with nano-ceramic particles, lithium salts, imidazole-based ionic liquids, and plasticizers. The polymer matrix is tailored to optimize mechanical strength and processing properties, while the nano-ceramic particles enhance ionic conductivity. The membrane thickness is precisely controlled to achieve optimal performance.

19. Organic-Inorganic Composite Solid Electrolyte with Single-Step Solution Processing for Sodium-Ion Batteries

PUYANG CAS HINA TECHNOLOGY CO LTD, 2019

Organic-inorganic composite solid electrolyte material and its preparation method for sodium-ion batteries, enabling improved performance and safety through enhanced ionic conductivity, mechanical properties, and processing characteristics. The material combines the benefits of both organic and inorganic electrolytes, offering a solid-state electrolyte that can replace conventional liquid electrolytes while maintaining diaphragm functionality. The preparation method enables the creation of this hybrid electrolyte through a single-step solution processing process, simplifying the manufacturing process compared to traditional liquid electrolyte production methods.

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20. Polymer Electrolyte with Perfluorosulfonimide Anions and Lithium Ion Complexation for Enhanced Conductivity

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Ionic liquid polymer for lithium-ion batteries with enhanced conductivity and lithium-ion migration properties. The polymer contains perfluorosulfonimide anions with weak coordination sites, which form a complex with lithium ions. This complex structure enables improved lithium ion migration and conductivity in lithium-ion batteries. The polymer is prepared through a novel reaction pathway that enables the formation of the complex with perfluorosulfonimide anions. The resulting polymer solid electrolyte exhibits superior lithium-ion conductivity and migration characteristics compared to conventional lithium-ion battery electrolytes.

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21. Method for Cross-Linking Polyethylene Oxide Polymer Films Using Polyamine and Glycidyl Ether

22. Solid-State Lithium-Ion Battery with Composite Solid Electrolyte Integrating Inorganic and Organic Materials

23. In-Situ Polymerization Method for Lithium-Ion Battery Electrolyte Membranes

24. Flexible Composite Polymer Electrolyte Membrane with Inorganic Powders and Variable Thickness for Lithium-Ion Batteries

25. Lithium-Ion Battery Electrolyte with Eight-Arm Liquid Crystal Block Copolymer and Polyethylene Glycol-Bromine Composite

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