Insulating Polymer Matrix Research Articles

Electrical and Thermal Properties of Surface-Modified Copper Nanowire/Polystyrene Nanocomposites through Latex Blending.

The incorporation of conductive nanofillers into an insulating polymer matrix commonly leads to nanocomposites with good electrical, thermal, and mechanical properties. In this study, copper nanowires (CuNWs) and polystyrene (PS) microspheres were synthesized along with the fabrication of CuNW/PS polymer nanocomposites. The electrical, thermal, mechanical, rheological, and morphological properties of the CuNW/PS nanocomposites were examined. The CuNWs were homogeneously dispersed in the PS matrix through latex blending. For the CuNW/PS nanocomposites, the storage modulus was higher than the loss modulus at all frequencies, indicating their elastic-dominant behavior. The electrical and thermal conductivities of the nanocomposites increased with an increasing CuNW content. Using a mixed dispersion of two monodisperse PS particles of 500 nm and 5 μm in diameter resulted in the highest electrical conductivity (ca. 10° S/m for 30 wt % nanofillers) among the nanocomposites. In addition, the introduction of silica- and polydopamine-coated CuNWs as nanofillers imparted insulation properties to the nanocomposites, with electrical conductivities to 10-10-10-8 S/m. When using 500 nm PS particles, the thermal conductivity of the surface-modified CuNW/PS nanocomposite at 30 wt % of CuNW was enhanced to 0.22 W/m·K compared to 0.17 W/m·K for its unmodified counterpart. We have achieved multiple innovative approaches, including the use of mixed particle sizes, surface modification of CuNW, and the exploration of elastic-dominant behavior. This enhanced thermal conductivity, coupled with the attainment of insulation properties, presents a distinct advantage for thermal interface material (TIM) applications.

A Sustainable Gel Polymer Electrolyte for Solid-State Electrochemical Devices.

Nowadays, solid polymer electrolytes have attracted increasing attention for their wide electrochemical stability window, low cost, excellent processability, flexibility and low interfacial impedance. Specifically, gel polymer electrolytes (GPEs) are attractive substitutes for liquid ones due to their high ionic conductivity (10-3-10-2 S cm-1) at room temperature and solid-like dimensional stability with excellent flexibility. These characteristics make GPEs promising materials for electrochemical device applications, i.e., high-energy-density rechargeable batteries, supercapacitors, electrochromic displays, sensors, and actuators. The aim of this study is to demonstrate the viability of a sustainable GPE, prepared without using organic solvents or ionic liquids and with a simplified preparation route, that can substitute aqueous electrolytes in electrochemical devices operating at low voltages (up to 2 V). A polyvinyl alcohol (PVA)-based GPE has been cast from an aqueous solution and characterized with physicochemical and electrochemical methods. Its electrochemical stability has been assessed with capacitive electrodes in a supercapacitor configuration, and its good ionic conductivity and stability in the atmosphere in terms of water loss have been demonstrated. The feasibility of GPE in an electrochemical sensor configuration with a mediator embedded in an insulating polymer matrix (ferrocene/polyvinylidene difluoride system) has also been reported.

Perforated Turbostratic Graphene As Active Layer in a Nonvolatile Resistive Switching Memory Device

Perforated turbostratic graphene (PTG) sheets have been synthesized from a natural waste material, dead bougainvillea bracts, using a single-step pyrolysis method, and a resistive switching (RS) memory device has been constructed with it for the very first time. Herein, the edges of these large-area multilayer graphene sheets are highly conducting due to the turbostratic stacking between the adjacent layers of the graphene sheets. These highly conducting PTG sheets embedded inside an insulating polymer matrix can act as an active layer for resistive switching memory devices. This hybrid structure shows nonlinear resistance change between two distinct resistance states by simple bias voltage variation. The trap-assisted space-charge-limited conduction can realize the high resistive state (HRS), whereas the low resistive state (LRS) takes place through direct conduction. To achieve the best performing device, a number of optimizations have been performed, like the variation of polymer matrices, variation of PTG and polymer concentration, active layer thickness variation, and top electrode area variation. The best performing device showed reproducibility of current–voltage data (>200 cycles), low power consumption (SET voltage <1 V), a high ON/OFF ratio (>104), a long retention time (>104 s), and a large number of endurance cycles (>103). High writing-read-erase-read speed and flexibility/bending cycle tests were also carried out on the best-performing device to examine its tenacity. The current PTG-based flexible RS memory device derived from a biowaste, dead bougainvillea bracts, can provide an important step toward developing green electronics.

Enhanced through-thickness electrical conductivity and lightning strike damage response of interleaved vertically aligned short carbon fiber composites

Through-thickness electrical conductivity of carbon fiber reinforced polymers (CFRPs) is a key characteristic that determines the severity of lighting strike-induced damage. Carbon Fibers (CFs) are inherently electrically conductive and therefore provide high conductivity in the direction of the fiber orientation. However, electrical conductivities through the thickness and orthogonal to the CF orientation in CFRPs are governed by the insulating polymer matrix present between CFs. In this work, through the thickness alignment of short CFs in between layers of CFRP laminates is demonstrated to improve the through-thickness electrical conductivity. Composites with interleaved vertically aligned short CF fibers (<150 μm) will be referred as V-fiber composites hereafter. The effect of the V-fiber on the lightning strike damage is evaluated against an artificial lightning strike of 100 kA (modified waveform A of SAE ARP-5412B standard). The improved through-thickness electrical conductivity of CFRP laminates (1.15 S/cm) through vertical alignment of short CFs was compared to reference CFRP laminates (0.13 S/cm) and was found to dissipate the artificial lightning strike current more efficiently. The surface damage after the artificial lightning strike in the V-fiber composites was reduced to 12.69 cm2 compared to the reference CFRP surface damage of 57.67 cm2, a 78% reduction. It was also demonstrated that Joule heat generated due to lightning strike on the composites was significantly less than the reference sample using infrared (IR) thermography. A high retention (up to 78%) of flexural properties (modulus and strength) was observed in V-fiber composites post lightning strike impact as compared to only 47% retention in the reference panel.

Composition and Surface Morphology Invariant High On–Off Ratio from an Organic Memristor

Material composition plays a crucial role in the device performance; thus, nonvolatile memory devices from a small molecule named 5-mercapto-1-methyl tetrazole (MMT) in an insulating polymer matrix of poly(4-vinyl pyridine) (PVP) were fabricated. The composition of the active material in the device was varied to observe its influence on the device’s electronic properties. The device with a more or less weight ratio of MMT has a much smoother surface morphology, whereas when the contributions of MMT and PVP were equal, the average surface roughness increased. However, the maximum on–off current ratio for all the devices is 105, suggesting that the MMT molecule does not show any change in its characteristic properties when surrounded by an insulating material. When the device was fabricated without the polymer matrix, the surface morphology of the device completely changed as it was filled with large holes. These holes provide short-circuited pathways for the current by forming the direct metal contact between the top and bottom electrodes. The carrier transport through these devices follows various conduction mechanisms. Some of the dominating conduction mechanisms are direct tunneling and trap-free and trap-assisted space–charge-limited conduction.

Investigation of electrical resistance and dielectric constant of Boron Nitride and Banana fiber reinforced epoxy polymer matrix composite

Nowadays, high thermal conductive and good electrical insulating materials gain attention for compact and sustainable design in power electronics instruments like transformers, switches, cables. To cater for these needs, Boron Nitride (BN)/Banana Fiber (BF)/Epoxy based polymer composite is proposed which exhibits good electrical resistance and low dielectric constant. Banana fiber is chosen as it contains few lumens among the fillers and offers good mechanical strength. Boron Nitride and Banana fiber are reinforced with epoxy resin to form highly insulating polymer matrix composite material. Various samples are fabricated, containing 1/3/5 μm BN particle size, 1/3/5 wt % of BN and 0/2/4 wt % of BF derived from Response surface methodology based Box Behnken Design model using design of experiments approach. Further, Analysis of Variance is performed to obtain optimized levels of parameters using regression equation in MINITAB software. Also, experimental results and optimized results are compared leading to error analysis. High resistance of 346.68 Giga-ohms (86.67 ×109 Ω-m resistivity) and minimum dielectric constant of 1.143 are obtained for combination of 3 wt % of BN, 2 wt % of BF and particle size of 3 μm which is considerable for good insulation purpose.

Thermal percolation and electrical insulation in composite materials with partially metallic coated fillers

We propose a type of thermal interface materials incorporating insulating nanowires with partially metallic coating in insulating polymer matrix. Large thermal conductivity can be obtained due to thermal percolation while the electrical insulation is maintained by controlling CMφ&amp;lt;φce and φ&amp;gt;φcth, where φ is the volume fraction of fillers, CM is the metallic coating fraction, and φce and φcth are the electrical and thermal percolation thresholds, respectively. The electrical conductivity of such composite materials can further be regulated by coating configuration. In this regard, we propose the concept of “thermal-percolation electrical-insulation,” providing a guide to design efficient hybrid thermal interface materials.

Characterizing and Optimizing Piezoelectric Response of ZnO Nanowire/PMMA Composite-Based Sensor.

Due to the outstanding coupling between piezoelectric and semiconducting properties of zinc oxide nanowires, ZnO NW-based structures have been demonstrating promising potential with respect to their applicability in piezoelectric, piezotronic and piezo-phototronic devices. Particularly considering their biocompatibility and biosafety for applications regarding implantable medical detection, this paper proposed a new concept of piezoelectric composite, i.e., one consisting of vertically aligned ZnO NW arrays and an insulating polymer matrix. First, the finite element method (FEM) was employed to drive optimization strategies through adjustment of the key parameters such as Young’s modules and the dielectric constant of the dielectric constituents, together with the density and dimension of nanowire (NW) itself. Second, to investigate the functionality of each individual layer of composite, different designed structures were fabricated and characterized in terms of electrical and piezoelectric properties. Next, experimental and simulation tests were performed, indicating that the decreasing thickness of the top poly(methyl methacrylate) layer (PMMA) can substantially enhance the piezoelectric sensitivity of the ZnO NW composite. Besides the further benefit of no polarization being needed, our material has a comparable charge coefficient (d33) with respect to other lead-free alternatives (e.g., BaTiO3), confirming the high sensing abilities of the developed structure based on vertically aligned ZnO NW arrays. Finally, a time-varying model combining piezoelectricity and electric circuit modules was investigated in detail, giving rise to an estimation of the d33 coefficient for ZnO NWs. Based on this study, the developed material is revealed to be highly promising in medical applications, particularly regarding the FFR technique, where coronary pressure can be measured through a piezoelectric sensor.

A comparison of thermally conductive polyamide 6‐boron nitride composites produced via additive layer manufacturing and compression molding

AbstractThermally conductive but electrically insulating polymer matrix composites are of great interest in many engineering applications such as thermal management applications (i.e., heat sinks in microelectronic packaging, cooling of mechatronic components and mechanisms). Among possible functional fillers, hexagonal boron nitride seems to be one of the most promising choice due to its high thermal conductivity, and in this work, it was used as filler of polyamide 6 matrix. The resulting composites were first prepared in the form of pellets, extruded into filaments, and successively 3D printed, with the aim to study and compare the thermal performances of the 3D printed samples to the ones manufactured using traditional compression molding technique. The thermal conductivity of 25% wt and 45% wt loaded compression molded samples were 1 and 2.5 W/mK, respectively, while the neat polymer showed a thermal conductivity of 0.29 W/mK. 3D printed samples showed the same trend, namely increasing thermal conductivity with filler amount, despite a great influence of the 3D printing processing parameters (i.e., melt rheology and printing temperature), which lower the resulting thermal conductivity. 3D printed 25% and 45% by weight loaded samples showed a through plane thermal conductivity of 0.67 and 0.92 W/mK, respectively, and in‐plane thermal conductivity of 0.96 and 1.52 W/mK due to the presence of porosity and filler alignment along the printing direction.

Stretchable OFET Memories: Tuning the Morphology and the Charge-Trapping Ability of Conjugated Block Copolymers through Soft Segment Branching

The mechanical properties and structural design flexibility of charge-trapping polymer electrets have led to their widespread use in organic field-effect transistor (OFET) memories. For example, in the electrets of polyfluorene-based conjugated/insulating block copolymers (BCPs), the confined fiberlike polyfluorene nanostructures in the insulating polymer matrix act as effective hole-trapping sites, leading to controllable memory performance through the design of BCPs. However, few studies have reported intrinsically stretchable charge-trapping materials and their memory device applications, and a practical method to correlate the thin-film morphology of BCP electrets with their charge-trapping ability has not yet been developed. In this study, a series of new conjugated/insulating BCPs, poly(9,9-di-n-hexyl-2,7-fluorene)-block-poly(δ-decanolactone)s (PF-b-PDLx, x = 1-3), as stretchable hole-trapping materials are reported. The linear and branched PDL blocks with comparable molecular weights were used to investigate the effect of polymer architecture on morphology and device performance. Moreover, the coverage area of the polyfluorene nanofibers on the BCP films was extracted from atomic force microscopy images, which can be correlated with the trapping density of the polymer electrets. The branched PDL segments not only improve stretchability but also tailor crystallinity and phase separation of the BCPs, thus increasing their charge-trapping ability. The OFET memory device with PF-b-PDL3 as the electret layer exhibited the largest memory window (102 V) and could retain its performance at up to 100% strain. This research highlights the importance of the BCP design for developing stretchable charge-trapping materials.

Thermal annealing effects on the morphology and charge transport of polymer semiconductor nanowires aligned in an insulating polymer matrix

Thermal annealing can profoundly affect the molecular ordering, orientation, morphologies, and charge transport of poly(3-hexylthiophene) (P3HT) nanowires (NWs) aligned within a polystyrene (PS) matrix. Upon thermal annealing, the structural and morphological changes of the aligned P3HT-NWs were systematically studied using static absorption spectroscopy, X-ray diffraction, atomic force microscopy, and polarized optical microscopy; the change in charge transport properties was investigated using macroscale charge carrier mobility measurements. Further, the thermal annealing temperature and duration were thoroughly correlated with the molecular ordering, orientation, and charge transport properties of the aligned P3HT-NW/PS blend films. It was revealed that charge transport of the aligned blend films is determined by the complicated interplay between molecular ordering, orientation, and morphologies, which are prone to change by post-thermal annealing conditions. The orientation of the aligned blend films decreased with increasing annealing temperature, while the molecular ordering improved as the temperature increased up to 150 °C, and then decreased with further increasing temperature. Significant morphological changes of the aligned blend films were observed after thermal annealing at 200 °C, owing to the remarkable increase in the thermally induced diffusion of the polymer chains. Consequently, the highest charge transport was measured in the aligned P3HT-NW/PS blend films annealed at 100 °C for 10 min. However, the charge transport was decreased by increasing either the annealing temperature or duration.

Simple scalable processing method for a polymer/inorganic hybridized electrolyte

The development of polymer/inorganic composite membrane hybrid electrolytes for use in lithium-ion batteries has significantly advanced the innovation of energy storage devices. These membranes consist of monolayered Li-ion-conducting particles that are firmly embedded in an insulating polymer matrix and can improve conductivity and mechanical characteristics. However, the scalability of producing one-particle-thick membranes remains a challenge. Here, we evaluate three different simple processes that may be used to produce composite membranes by examining scanning electron microscope images and measuring conductivity. The conductivity of the membrane produced by the optimal method was 0.49 mS/cm at 20 °C, which is approximately 5.5 times higher than that of a commercially produced LATP-sintered disk. The optimal process described here could be used in industrial applications of both all-solid batteries in electric vehicles and flexible all-solid-state batteries in wearable devices.

Unsymmetrical Small Molecules for Broad-Band Photoresponse and Efficient Charge Transport in Organic Phototransistors.

Organic photosensitizers have been investigated as effective light-sensing elements that can promote strong absorption with high field-effect mobility in organic phototransistors (OPTs). In this study, a novel organic photosensitizer is synthesized to demonstrate broad-band photoresponse with enhanced electrical performance. An unsymmetrical small molecule of a solubilizing donor (Dsol)-acceptor (A)-dye donor (Ddye) type connected with a twisted conjugation system is designed for broad-band detection (ranging from 250 to 700 nm). This molecule has high solubility, thereby facilitating the formation of uniformly dispersed nanoparticles in an insulating polymer matrix, which is deposited on top of OPT semiconductors by a simple solution process. The broad-band photodetection shown by the organic photosensitizer is realized with improved mobility close to an order of magnitude and high on/off current ratio (∼105) of the organic semiconductor. Furthermore, p-type charge transport behavior in the channel of the OPT is enhanced through the intrinsic electron-accepting ability of the organic photosensitizer caused by the unique molecular configuration. These structural properties of organic photosensitizers contribute to an improvement in broad-band photosensing systems with new optoelectronic properties and functionalities.

A Comparative Study of Unsaturated Resin/Graphite Microchip and Nano-Graphite Microchip Composites Prepared by Electric Field

Graphite microsheets as conductive fillers have their unique advantages compared with a traditional conductive fillers such as carbon black. Graphite microsheets have a large diameter-thickness ratio, which greatly reduces the percolation threshold of conductive composite system with graphite microsheets as conductive fillers. Under the action of applied electric field, the orientation of graphite microsheets in polymers changes the distribution of graphite in polymers. The conductivity of the composites can be changed. Because of the large diameter-thickness ratio, the nanographite microchip is easier to form conductive pathways in the composites. It can be imagined that the conductivity of ordinary graphite nanosheets can be achieved at a lower content as the ultra-fine dispersed graphite nanosheets. With the use of the conductive materials stated above and through the effect of applied electric field, we were able to get a new method of processing materials and functional materials with a higher design and better comprehensive performance. As conductive fillers, graphite nanosheets can be induced by the AC electric field in unsaturated polyester resin and then prepared oriented unsaturated polyester resin/graphite nanosheets composite. Compared with one-dimensional structure of carbon nanofiber and carbon nanotubes, two-dimensional lake-like shape graphite nanosheets have high aspect ratio. Applying an electric field during the preparation of the composite, graphite nanosheets can be oriented conquering the shearing action of viscous in an insulating polymer matrix due to the cooperative effect of the electric torque exerted by the electric field directly on the nanosheets. Finally, through the change of electric current of composite materials prepared in different media under electric field, we determine the influence factors of conductivity of composite materials and the conductive mechanism of nano-graphite micro-sheets under electric field.

Enhanced Dielectric Properties of a Poly(dimethyl siloxane) Bimodal Network Percolative Composite with MXene.

Excellent comprehensive dielectric properties (including dielectric constant and loss) are essential for electromechanical transducers. This work introduced a bimodal network composite with poly(dimethyl siloxane) (PDMS) and delaminated Ti3C2Tx sheets (d-Ti3C2Tx) modified with hyperbranched polysiloxane (HPSi) (referred to as HPSi-d-Ti3C2Tx). Before the final cross-linking, HPSi-d-Ti3C2Tx, trapped with short-chain PDMS (CS-PDMS) and long-chain PDMS (CL-PDMS), was pre-reacted, which formed a distinct bimodal network structure. d-Ti3C2Tx/PDMS and HPSi-d-Ti3C2Tx/PDMS composites with different filler loadings were prepared, and their percolation thresholds (fc) were 1.32 and 1.43 vol %, respectively The dielectric constant of 1.40 vol % HPSi-d-Ti3C2Tx/PDMS is 23.7 at 102 Hz, which is 1.5 times that of 1.28 vol % d-Ti3C2Tx/PDMS and 8.5 times that of pure PDMS. Meanwhile, the dielectric loss of HPSi-d-Ti3C2Tx/PDMS composite is still relatively small (0.11 at 103 Hz). The origin of dielectric property optimization of the composite is attributed to the boundary capacitor model, the accumulated charges at the interfaces between the conductive filler and the insulating polymer matrix of the composite, and the distinct bimodal network structure.

Promising PVC/MXene based flexible thin film nanocomposites with excellent dielectric, thermal and mechanical properties

Miniaturization of electronic gadgets continuously demands for the improved dielectric and flexible polymer composites. MXene flakes are considered as ideal electrically conductive 2D fillers inserted into the insulating polymer matrix to boost the dielectric performance of the polymer composites while maintaining superb flexibility. The present work is focused on the synthesis and characterization of strong and flexible PVC/MXene nanocomposites, possessing high dielectric constant and minimum energy loss, for their use in energy storage electronic applications. For this purpose, highly conductive delaminated MXene (DM) was prepared by HF-etching before delamination by DMSO and water and followed by high-temperature annealing. The prepared conducting DM was then inserted into insulating PVC in various concentrations by a simple solution casting method aided by strong sonication. The embedded DM in PVC facilitates the formation of conducting-insulating-conducting network CICN by increasing the AC conductivity of the obtained nanocomposites, which is explained according to the percolation theory. At the percolation threshold of 10 wt% MXene, the maximum number of PVC/MXene interfaces promotes interfacial polarization which endows the fabricated nanocomposites with high dielectric characteristics. The composite achieves a highest dielectric constant of 11800, which encompasses all the previous reported values. Also, low dielectric loss of 1.31 originates from the increase in electrical conductivity of the entire composite which in turn arises from the strong tunneling effect of conducting DM in PVC matrix. Moreover, thin films of the obtained composites also display very high flexibility, increased thermal conductivity of 3.48 W/mK, an extraordinary thermal stability (683.8°C) and good mechanical stability, as the tensile strength reaches to 174.08%. Afterwards, the respective optimized nanocomposites were characterized by SEM, XRD and FTIR convincing the strong interfacial interaction and improved dispersion of DM flakes into PVC matrix. These unique features of our prepared PVC/MXene flexible thin films support their tremendous potential for modern dielectric applications.

Inducing Molecular Aggregation of Polymer Semiconductors in a Secondary Insulating Polymer Matrix to Enhance Charge Transport

Polymer semiconductors (PSCs) are a desirable class of materials for next-generation electronics. However, the conformational complexity associated with macromolecules, as well as the presence of u...

3D-Printed Photoactive Semiconducting Nanowire–Polymer Composites for Light Sensors

We demonstrated 3D-printed photoactive composites for light sensors. The composites consist of semiconducting polymer nanowires dispersed in an insulating polymer matrix through a thermo- or photocuring process. The nanowires formed percolated networks for charge-carrier collection at a very low nanowire volume concentration. Photodetectors had been fabricated with such composites and obtained a low leakage current density of 25 nA cm–2, a large conductivity change of 18025 times upon light irradiation (1 sun), and a high specific detectivity of 4.5 × 1010 Jones. The composite precursors before curing had been used as paints on different surfaces including wood, cardboard, and glass fiber cloth to create photoactive coatings on these surfaces. The precursors had also been used for 3D printing to create photoactive structures with a mechanical modulus of 4 GPa and an ultimate strength of 36 MPa.

Dielectric Properties of Epoxy-Matrix Composites with Tungsten Disulfide Nanotubes

Addition of conductive nanotubes to an insulating polymer matrix has been proven as an efficient strategy that can improve the electromagnetic shielding performance, due to the high aspect ratio of nanotubes. Herein, a set of epoxy-matrix composites filled with 0.15-1.6 vol% of tungsten disulfide (WS2) nanotubes being of 30-120 nm in diameter and 5-20 μm in length has been produced. Electromagnetic properties of the prepared composites were probed in the frequency range from 20 Hz to 1 MHz in a temperature range from 250 K to 500 K. Broadband properties of these materials are controlled by the dynamics of epoxy resin molecules, and no electrical percolation was observed up to the highest concentration (1.6 vol%) of WS2 nanotubes. The value of dielectric permittivity for all composites is not bigger than 6 at room temperature and 1 kHz frequency, and the electrical conductivity of composites is about 10-6 S/m at 500 K, which demonstrate that the composites are suitable for antistatic applications at higher temperatures. The relaxation time follows the Vogel-Fulcher law, and the Vogel temperature T0 has the minimum for the WS2 nanotube concentration 0.15 vol%. Above 410 K, the electrical conductivity determines the properties of the investigated composites due to nonzero electrical conductivity of epoxy resin. The value of DC electrical conductivity for pure epoxy at T=450 K is 0.3 μS/m, while the DC conductivity of the composites slightly increases with the WS2 concentration. Therefore, the electrical contacts between WS2 nanotubes and polymer matrix are rather ohmic. Additionally, the activation energy is almost independent on the concentration of WS2. However, it is higher in composites than in pure epoxy resin.

Improvement of preparation process for Li-ion conducting membranes composed of monolayered inorganic electrolyte particles and insulating polymer matrix

This article reports the electrochemical performance of hybridized Li-ion conductive membranes consisting of a monolayer of Li-ion-conducting particles uniformly embedded in an insulating polymer matrix. The prepared hybridized Li-ion conductive membranes with the Li1.3Al0.3Ti1.7P3O12 (LATP) solid electrolyte and a cycloolefin polymer were studied via AC impedance spectroscopy and typical battery testing. The conductivities of the hybridized Li-ion conductive membranes were 0.53 mS cm−1 at 20 °C and 0.22 mS cm−1 at −10 °C, approximately 6 and 15 times higher, respectively, than those of the commercial LATP sintered disc. In addition, the activation energy (17.2 kJ mol−1) was in agreement with that of the bulk of LATP and approximately half that of the commercial LATP sintered disc. The membranes were used in batteries and the possibility of further improvement was referred from the results of their overpotentials and surface analyses.