TiO3 Solid Electrolyte Research Articles

Electrochemical performance enhancement of perovskite-type Li0.3La0.57TiO3 ceramic electrolyte by controlling synthesis parameters

This study investigates the enhancement of the electrochemical performance of perovskite-type Li0.3La0.57TiO3 (LLTO) solid electrolytes through the optimization of synthesis parameters of a sol-gel process. The primary focus lies in examining the impact of calcination temperature on the structural, morphological, and electrochemical properties of LLTO. Our findings reveal that controlling the calcination temperature significantly influences the grain boundary resistance and overall ionic conductivity. The optimal calcination temperature was identified to be 800 °C, yielding a remarkable improvement in ionic conductivity at grain boundaries (0.88 mS/cm), and total ionic conductivity (0.54 mS/cm), at 30 °C. This enhancement is attributed to the refined microstructure, increased density, and reduced porosity, which collectively facilitate lithium-ion diffusion. These advancements in LLTO electrolytes present promising implications for their application in all-solid-state lithium-ion batteries, offering a safer and more efficient alternative to conventional liquid electrolyte systems.

Composition, microstructure, and ionic conductivity relationships in cerium doped Li0.5La0.5TiO3 solid electrolyte

The increasing necessity of high ionic conductor for solid state electrolytes implies the enhancement of our understanding in the relationship between doping-microstructure-ionic conductivity. In the current study, Li0.5La0.5-xCexTiO3 (0.00 ≤x ≤ 0.05) perovskites are obtained using the sol-gel method to evaluate the effects of cerium doping on microstructure and conductivity. The results confirms that all samples present a tetragonal perovskite structure with the lowest energy gap of 1.67eV for x = 0.01 of Ce3+, this particular composition present an average grain size of 2.026 μm and the highest relative density (92.02 %), bulk and grain boundary conductivities in the order of 1.949 × 10−3 S/cm and 1.671 × 10−6 S/cm, respectively at room temperature. These conductivity values are approximately an order of magnitude higher than the Ce-free material, thanks to the optimized relative density and adequate grain size.

Fabrication and Characterization of LiNi1/3Mn1/3Co1/3O2/Li0.6La0.4TiO3/Li4Ti5O12 Full Cell All-Solid-State Thin Film Li-Ion Batteries for Energy Applications

Recent days, natural calamities caused by the global warming and climate changes are major concern for the entire globe and there is a pressing need to address such issues to save the mankind from further havoc and devastation. To reduce the carbon emission, countries are shifting dramatically towards renewable sources for their energy needs for their day-to-day life. Li ion batteries are in the forefront of the battle towards the sustainable growth and development due to their high energy density and renewable in nature. In the present case, we report on development of thin film based all-solid-state batteries (ASSB) for energy applications. LiNi1/3Mn1/3Co1/3O2 (NMC), Li0.6La0.4TiO3 (LLTO) and Li4Ti5O12 (LTO) materials are employed as a cathode, solid electrolyte and anode layers for fabricating a full cell all-solid-state thin film batteries. All the layers are fabricated employing RF sputtering technique. Before fabricating the full cell, individual layers are fabricated and their electrochemical and/or ionic conductivity properties are explored. Li0.6La0.4TiO3 solid electrolyte thin films are seen to exhibit room temperature in-plane ionic conductivity in the order of 10-3 S/cm. NMC thin film with the thickness of 100 nm exhibits specific capacity of 91 µAh/cm2 and the redox peaks at 3.8 V and 3.5 V. LTO anode thin films shows the specific capacity close to 100 mAh/cm2and the redox peaks around 1.5 V. XRD pattern of NMC/LLTO/LTO full cell shows the diffraction peaks corresponding to all the three layers. Cross-sectional scanning electron microscope (SEM) image indicates the uniform coating and presence of all the layers. High-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) along with the energy dispersive X-ray is employed to image the cross-sectional details and the elements present in each layer of the full cell all-solid-state thin film battery. Impedance spectroscopy was employed to calculate the total conductivity of the fabricated full cell. Obtained results indicates that the full cell NMC/LLTO/LTO thin film batteries can be fabricated employing a sputtering technique for the energy applications. Figure 1

Effect of Bi2O3 on the ion migration and interfacial properties of Li0.33La0.557TiO3 solid electrolytes

The poor interface incompatibility with Li anode and low ionic conductivity have hindered perovskite-type electrolyte’s practical application. In this work, solid electrolytes of Li0.33La0.557TiO3 + x wt% Bi2O3 for solid state batteries were prepared by solid-phase sintering method. The ionic conductivity of LLTO reaches a maximum of 2.71 × 10–5 S·cm–1 at 1 wt% Bi2O3 doping. The critical current density of Li0.33La0.557TiO3 + 1 wt%Bi2O3 can reach 0.16 mA and still operate normally after 300 h of cycling. Li0.33La0.557TiO3 + 1 wt% Bi2O3 solid-state battery displays a high initial discharge capacity of 133.1 mAh/g and capacity retention of 98.0% after 40 cycles.

Identifying the Phonon Contributions to Li+ Hop in La0.5Li0.5TiO3 Solid Electrolyte

Ion diffusion is important in a variety of applications, yet fundamental understanding of the interaction of lattice vibrations (phonons and vibrational motifs) and the mobile species in solids is still missing. Particularly, for Li super ionic conductors (LISICONs), several studies have reported on the important role of the poly-anion octahedral rotations (rocking modes) in facilitating solid-state Li+ ion migration.[1], [2] However, direct calculation of the contribution of these rocking modes to the Li+ hop is missing, and the provided arguments in these reports are mostly based on establishing correlations between different properties of the rocking modes and the migration properties of the hopping Li+ ion without directly quantifying the contribution of the rocking modes to the Li+ hop. For instance, rocking modes have been argued to be able to (i) provide a softer lattice environment for Li+ ion vibration,[3] (ii) increase the bottleneck area of diffusion (4-O square area),[2] (iii) induce additional force on the carrier sublattice,[1] and (iv) maintain a relatively constant coordination number for Li+ ion during its hop[1] – all conducive to Li+ hop in the lattice. Although insightful, we still lack understanding of the exact vibrational frequencies (density of states) of the rocking modes, and, more importantly, the degree of their contribution to Li+ hop with respect to other phonon modes in the structure. In this work, using a combination of ab initio nudged elastic band (NEB) and lattice dynamics calculations based on the recently proposed formalism,[4] we identify the direct contributions of all phonons, including the rocking ones, to Li+ hop in the perovskite solid-state Li+ conductor Li0.5La0.5TiO3 (LLTO).We set up our NEB Li+ hop calculations considering (i) different orderings of the LLTO lattice,[5] and (ii) different Li+ hopping mechanisms (single and concerted (cooperative)) that can occur in the LLTO lattice.2 To sample such a high degree of complexity, we performed 22 independent NEB calculations of Li+ hop in three different LLTO structures with distinct Li|La orderings and based on two different ion hop mechanisms (single and concerted). Our calculations determined that the following two groups of vibrational modes dominate the contributions to the Li+ hop in the LLTO lattice: (i) rocking modes, and (ii) modes that induce large vibrational energies on the hopping Li+ along its hopping direction. Specifically, our results confirmed that the top 5% (10%) contributing modes to the Li+ hop in the LLTO lattice were responsible for 48% (61%) of the total contributions to the Li+ hop, and the two rocking and highly energetic modes comprised >95% (>85%) of these top 5% (10%) contributing modes. Notable from our calculations was that the rocking modes were only present in the < 5.5 THz frequency region, and in this < 5.5 THz frequency region, they comprised 33% of the vibrational modes and contributed 50% to all the possible contributions to the Li+ hop in this low frequency THz region. Moreover, through static modal excitement calculations, we determined that highly contributing rocking modes of vibration were important in solid-state Li+ ion migration because of their ability to (i) increase the O-4 square bottleneck area of conduction[6] and (ii) amplify the force on the hopping Li+ ion. In summary, our observations demonstrated the strong importance of the THz vibrational region to Li+ hop in the lattice, which can be accessible for further explorations using THz spectroscopy techniques to deepen our understanding of the relation between solid-state transport of Li+ and different vibrational motifs in the lattice.

Li0.5La0.5TiO3 as an Ionic Conducting Additive Enhancing the High-Voltage Performance of LiNi0.8Mn0.1Co0.1O2 Cathodes in Lithium-Ion Batteries.

Although high-voltage (e.g., >4.3 VvsLi) operation can increase specific capacity and energy of Ni-rich NMC cathodes, it accelerates the oxidative decomposition of electrolytes and surface degradation of NMC cathodes, leading to rapid capacity fading. This work presents a novel approach that employs Li0.5La0.5TiO3 (LLTO) solid-electrolyte as a Li-ion conductor and surface passivation agent to stabilize the cathode/electrolyte interphase (CEI) layer of the LiNi0.8Mn0.1Co0.1O2 (NMC811) cathode and enhance its high-voltage performances. The LLTO particles improve Li-ion transportation across the CEI layer, as evidenced by its reduced impedance in Nyquist plots. Furthermore, passivation of CEI by LLTO mitigates parasitic reactions (e.g., transition metal dissolution) that occur on the graphite solid electrolyte interphase layer during extended cycles of pouch-cells. As a result, pouch-cells with the 1 or 5 wt % LLTO-blended NMC811 cathodes can deliver 19-23% increase in specific capacity and improved cycle life (1000 cycles) at high voltages (up to 4.4 V), comparing to bare NMC811 cathodes. Post-mortem characterization of pouch-cells quantitatively identified the degradation sources of NMC811 cathode at high-voltages, which highlighted the improvement mechanisms of LLTO blended-cathodes.

Self-Assembled Epitaxial Cathode-Electrolyte Nanocomposites for 3D Microbatteries.

The downscaling of electronic devices requires rechargeable microbatteries with enhanced energy and power densities. Here, we evaluate self-assembled vertically aligned nanocomposite (VAN) thin films as a platform to create high-performance three-dimensional (3D) microelectrodes. This study focuses on controlling the VAN formation to enable interface engineering between the LiMn2O4 cathode and the (Li,La)TiO3 solid electrolyte. Electrochemical analysis in a half cell against lithium metal showed the absence of sharp redox peaks due to the confinement in the electrode pillars at the nanoscale. The (100)-oriented VAN thin films showed better rate capability and stability during extensive cycling due to the better alignment to the Li-diffusion channels. However, an enhanced pseudocapacitive contribution was observed for the increased total surface area within the (110)-oriented VAN thin films. These results demonstrate for the first time the electrochemical behavior of cathode–electrolyte VANs for lithium-ion 3D microbatteries while pointing out the importance of control over the vertical interfaces.

Atomically Intimate Solid Electrolyte/Electrode Contact Capable of Surviving Long-Term Cycling with Repeated Phase Transitions

The electrode-electrolyte contact issue within the composite electrode layer is a grand challenge for all-solid-state Li batteries. In order to achieve cycling performances comparable to Li-ion batteries based on liquid electrolyte, the aforementioned solid-solid contact not only needs to be sufficiently thorough but also must tolerate repeated cycling. Simultaneously meeting both requirements is rather challenging. Here, we discover that epitaxy may effectively overcome such bottlenecks even when the electrode undergoes repeated phase transitions during cycling. Through epitaxial growth, the perovskite Li0.33La0.56TiO3 solid electrolyte was found capable of forming atomically intimate contact with both the spinel Li4Ti5O12 and rock-salt Li7Ti5O12. In contrast to conventional expectations, such epitaxial interfaces can also survive repeated spinel-to-rock-salt phase transitions. Consequently, the Li4Ti5O12-Li0.33La0.56TiO3 composite electrode based on epitaxial solid-solid contact delivers not only a rate capability comparable to that of the surry-cast one with solid-liquid contact but also an excellent long-term cycling stability.

Low temperature synthesis of Li0.33La0.55TiO3 solid electrolyte with Al3+ doping by a modified Pechini method

Low temperature synthesis of Li0.33La0.55TiO3 solid electrolyte with Al3+ doping by a modified Pechini method

Fabrication of LiFePO&lt;sub&gt;4&lt;/sub&gt;-Based Composite Cathode Deposited on LLTO Li-Ion Conducting Solid Electrolyte via Slurry Coating and Hot-Pressing

LiFePO4 (LFPO)-based composite cathode was deposited on Li0.35La0.55TiO3 (LLTO) solid electrolyte via slurry coating method. A composite cathode comprising of LiFePO4, LLTO, and carbon black (CB) were mixed together in a slurry and deposited on a dense LLTO pellet substrate. The effects of heat treatment temperature and hot-pressing in the structure and densification of the deposited composite cathode were investigated. Cathode component precursors were analyzed for its particle size distribution using particle size analyzer and revealed a bimodal particle size distribution for each component materials. Structural characterization using X-ray powder diffraction (XRD) analysis revealed that distinct XRD peaks were observed which can be attributed to LFPO and LLTO for the deposited as-dried and heat treated (450 °C ) composite cathodes. Surface and cross-sectional SEM images revealed that hot-pressing provided denser morphology with smaller thickness as compared to the just as-dried and heat treated samples without the application of temperature with pressure.

Stabilization of Li0.33La0.55TiO3 Solid Electrolyte Interphase Layer and Enhancement of Cycling Performance of LiNi0.5Co0.3Mn0.2O2 Battery Cathode with Buffer Layer.

All-solid-state batteries (ASSBs) are attractive for energy storage, mainly because introducing solid-state electrolytes significantly improves the battery performance in terms of safety, energy density, process compatibility, etc., compared with liquid electrolytes. However, the ionic conductivity of the solid-state electrolyte and the interface between the electrolyte and the electrode are two key factors that limit the performance of ASSBs. In this work, we investigated the structure of a Li0.33La0.55TiO3 (LLTO) thin-film solid electrolyte and the influence of different interfaces between LLTO electrolytes and electrodes on battery performance. The maximum ionic conductivity of the LLTO was 7.78 × 10−5 S/cm. Introducing a buffer layer could drastically improve the battery charging and discharging performance and cycle stability. Amorphous SiO2 allowed good physical contact with the electrode and the electrolyte, reduced the interface resistance, and improved the rate characteristics of the battery. The battery with the optimized interface could achieve 30C current output, and its capacity was 27.7% of the initial state after 1000 cycles. We achieved excellent performance and high stability by applying the dense amorphous SiO2 buffer layer, which indicates a promising strategy for the development of ASSBs.

Synthesis of textured Li0.33La0.55TiO3 solid electrolytes by molten salt method

Li0.33La0.55TiO3 (LLTO) with perovskite structure has very high grain conductivity. In this article, textured LLTO is synthesized by molten salt method. The X-ray diffraction (XRD) and field emission-scanning electron microscopy (FE-SEM) reveal that the reaction temperature and molten salts have effect on the template growth of LLTO. When the temperature does not reach the synthetic temperature of LLTO, some intermediate phases appear. As the temperature increases, the morphology of LLTO samples gradually changes from a rod-like structure to a sheet-like one. It is demonstrated that textured LLTO prepared by molten salt method shows highly (200) preferred orientation with a Lotgering factor of 0.66. The relative density of LLTO pellets reaches 94.9% together with a relatively high ionic conductivity of 2.70 × 10−5 S/cm. The growth mechanism of textured LLTO is discussed in terms of temperature- and molten salt-dependent diffusion of Ti elements; furthermore, the stable environment formed by LiCl–KCl molten salt can promote its preferential growth.

A study on Li0.33La0.55TiO3 solid electrolyte with high ionic conductivity and its application in flexible all-solid-state batteries.

As flexible all-solid-state batteries are highly safe and light weight, they can be considered as candidates for wearable energy sources. However, their performance needs to be first improved, which can be done by using highly conductive solid-state electrolytes. Herein, we prepare a crystallized and amorphous LLTO electrolyte through magnetron sputtering and investigate the effect of heat treatment on its ionic conductivity. The maximum ionic conductivity of the electrolyte is 9.44 × 10-5 S cm-1 at 140 °C. Electrode fracture after multiple cycles is the chief reason for the failure of solid-state batteries. To improve their cycle performance, we use LiNi0.5Co0.3Mn0.2O2 (NCM) with a volume change rate of 5% as the cathode and LTO with a volume change rate of 2% as the anode. A battery with a high output voltage using an internal series is prepared to enhance its application value. The output voltage of a single-layer NCM/LLTO/LTO battery is 2-2.4 V, while that of a two-layer NCM/LLTO/LTO battery can be 4.8 V in series. Owing to the small volume change rate of the electrode, the battery can be cycled up to 500 times, and the capacity of the battery remains at 89.2% of the initial state even after bending.

One-step low-temperature synthesis of Li0.33La0.55TiO3 solid electrolytes by tape casting method

Li0.33La0.55TiO3 (LLTO) is a solid Li-ion conductor with high bulk ionic conductivity. However, a high processing temperature, typically around 1300 °C, is generally required for obtaining its crystallization. In this work, LLTO was successfully synthesized at temperatures as low as 900 °C by tape casting method. Thermogravimetric analysis was carried out on the precursors for clarifying the weight loss and related phase transformations, and powder X-ray diffraction analysis was performed on the final products for verifying the crystallinity and phase purity in the low-temperature-processed LLTO electrolytes. The morphology of the synthesized LLTO powders was observed by scanning electron microscopy for understanding the microstructural evolution with increase of the sintering temperature. The ionic conductivity and activation energy of LLTO solid electrolytes were measured. A typical ionic conducting behavior with a moderate total conductivity of 4.3 × 10−6 S/cm and a quite low activation energy of 0.29 eV was obtained in the 900 °C-derived LLTO sample. When the processing temperature was raised to 1350 °C, the total ionic conductivity was further enhanced, reaching 6.13 × 10−5 S/cm. When the LLTO pellets were subject to cold isostatic pressing, the low-temperature (900 °C)-processed LLTO sample also presented a high conductivity of 2.1 × 10−5 S/cm. This work sheds light on the low-temperature synthesis of LLTO-based solid electrolytes for solid-state lithium battery applications.

Effect of Sn or Ta doping on the microstructure and total conductivity of perovskite Li0.24La0.587TiO3 solid electrolyte

Perovskite-structured Sn- or Ta-doped Li0.24–(q–4)xLa0.587Ti1–xMxO3 (LLTMxO, M = Sn or Ta, q is equal to the valence of M, x = 0, 0.02, 0.04, 0.06, 0.08) solid electrolytes are prepared by the pressureless sintering method for Li ion batteries. The phase composition, microstructure and electrical performance as a function of the type of doping elements and the amounts corresponding are studied by XRD, Raman spectrometer, SEM and electrochemical impedance spectroscopy. The LLTMxO pellets sintered at 1350 °C for 12 h have high relative densities (96.2%–97.9%) and high conductivities, where the total conductivity of LLTTa0.04O and LLTSn0.02O reach 4.09 × 10−4 S cm−1 and 2.98 × 10−4 S cm−1 at room temperature (RT) respectively. Compared with the pure specimen (1.52 × 10−4 S cm−1), the total conductivities of the doped specimens are more than doubled. In addition, Sn or Ta doping can significantly reduce the activation energy, with LLTTa0.04O exhibiting the low activation energy of 0.31 eV. The improvement in the total conductivity is attributed to the expansion of the Li ion transmission channels, the improvement of the relative density and the rise in the Li ion vacancy concentration, which are all resulted from the effect of dopant.

Effects of B-site ion (Nb5+) substitution on the microstructure and ionic conductivity of Li0.5La0.5TiO3 solid electrolytes

Nb-doped lithium lanthanum titanate (LLTO) ceramic electrolytes were fabricated by the conventional solid-state reaction method. Effects of Nb5+ substitution on the microstructure and ionic conductivity of LLTO were investigated systematically. It is found that the 4 at.% Nb-doped Li0.5La0.5TiO3 sintered at 1350 °C for 12 h shows the minimum amount of pores in microstructure and the highest total conductivity, 1.04 × 10−4 S/cm, being 1.6 times of that without Nb addition. Therefore, it is proved experimentally that a proper amount of Nb doping could be an effective and facile approach to improve the LLTO’s microstructure and total conductivity, thus making Nb-doped LLTO a good solid electrolyte candidate for use in lithium-ion batteries.

Cu incorporated perovskite Na0.5Bi0.5TiO3 oxygen-defect conductor as NO2 sensor using CuO sensitive electrode

In this work, perovskite Na0.5Bi0.5TiO3 is applied as oxygen-defect conductor of NO2 sensor fabricated with CuO as the sensing electrode and Pt as reference electrode. Transition metal ion Cu2+ serves as a dopant of Na0.5Bi0.5TiO3 at B site in view of its dual functions in both creating as many oxygen vacancies as possible and extending the length of the triple phase boundaries together with CuO sensing electrode. The phase transformation from the cubic to rhombohedral phase occurs in the process of increasing Cu2+ contents, resulting in greater lattice distortion and thus generating more oxygen vacancies. The expansion of the lattice volume and the overflowed Bi2O3 promote oxygen hopping in the [BO6]∝ chains of the solid electrolyte. The electrochemical results indicate that the Na0.5Bi0.5Ti0.85Cu0.15O3-δ sensor exhibits excellent response-recovery characteristics with high sensitivity (24.49 nA/ppm) upon exposed to 500 ppm NO2 at 500 °C. The possible coexistent gases affect little on the response current of the sensor towards NO2 gas. The long-term stability measurement illustrates that there is only a slight 1.36 μA drop in response current value after aging storage for one and a half months. The performances of the sensors based on non-rare-earth Cu-doped Na0.5Bi0.5TiO3 solid electrolytes exhibit the better-off application prospect with low cost at low-medium temperature.

Dielectric properties and I-V characteristics of Li0.5La0.5TiO3 solid electrolyte for ceramic supercapacitors

Solid electrolyte is crucial important for the developing of next generation supercapacitors. Tetragonal perovskite Li0.5La0.5TiO3 (LLTO) solid electrolyte ceramics were prepared by using conventional solid-state reaction method. Clear interfaces between the metal electrodes (Ag, Au or Pt) and the LLTO ceramics were observed. Nominal colossal permittivity at low frequency and strong frequency dispersion were observed in LLTO samples with different metal electrodes. The leakage currents decrease exponentially after the application of a stepwise DC voltage and show dramatic differences between different electrodes. The current-voltage (I-V) characteristic curves also indicate the differences, where the peak currents at maximum 5 V loading are 5.1 nA for sample with Ag electrode, 138.9 nA for Au electrode and 13.5 μA for Pt electrode. In addition, there is a clear redox current peak at about 4 V in LLTO/Pt sample and a blurred peak in LLTO/Au sample at around 2 V, which indicates an electrochemical reaction between LLTO and Pt/Au electrodes. These differences are attributed to the redox reaction of the Schottky contact interface between samples and electrodes. These interfacial I-V characteristics between LLTO and metal electrodes help us to understand the underlying mechanism in the future solid electrical double layer ceramic supercapacitors.

Structural and Electrical Effects of Y-doped Li0.33La0.56−xYxTiO3 Solid Electrolytes on All-Solid-State Lithium Ion Batteries

Li0.33La0.56TiO3 (LLTO) solid state electrolytes have been considered as candidates to substitute for organic liquid electrolytes in lithium batteries. LLTO consist of a mixture of cubic phases with Pm3m symmetry (α-LLTO) and with tetragonal P4/mmm symmetry (β-LLTO). The α-LLTO phase has a higher Li ion conductivity than the β-LLTO phase. However, α-LLTO is characterized by high lattice strain, which induces the formation of β-LLTO due to the different atomic sizes of Li+ (0.76 A) and La3+ (1.03 A). In this study, to reduce lattice stress, we prepared Y-doped Li0.33La0.56−xYxTiO3 (x = 0.02, 0.05, 0.1) by using the sol-gel method. Because the ionic radius of Y3+ is 0.90 A, that is, larger than that of Li+ (0.76 A) and smaller than that of La3+ (1.03 A), Y3+ suppresses the lattice distortion that prevents the formation of α-LLTO. The structural, morphological, and electrical characteristics of pure and Y3+-doped LLTO were investigated. The results show that Li0.33La0.46Y0.1TiO3 exhibits a better bulk conductivity (σ = 9.51 × 10−4 S cm−1) at 25 °C due to the increasing volume fraction of the more conductive α-LLTO phase.

FABRICATION AND ELECTROCHEMICAL EVALUATION OF THE LITHIUM BATTERY, Li0.5La0.5TiO3/LiFePO4-C INTERFACE

The Li0.5La0.5TiO3 and LiFePO4/C has been prepared using sol-gel method for its interface analysis towards its application for all solid state assembly. The LiFePO4cathode material and Li0.5La0.5TiO3 solid electrolyte has been individually tested for its electrochemical reversibility. The thin film battery assembly shows severe capacity fading, which results in electrochemically non active with the chosen anode materials. In order to verify the electrochemical activity and interaction of Li0.5La0.5TiO3-LiFePO4/C interface the mixture has been tested for its electrochemical reversibility. The Li0.5La0.5TiO3-LiFePO4/C interface exhibits well resolved oxidation-reduction hype which verifies its suitability towards all solid state assemblies.