Rechargeable Li-ion Batteries Research Articles

Developing the processing stages of carbon fiber composite paper as efficient materials for energy conversion, storage, and conservation

Carbon is a wonder material and has served the mankind since the inception of civilization in a variety of ways. Among its different forms, carbon fibers are especially known for their conductivity and favorable strength to weight ratio. Here the development of PAN based carbon fibers embedded in a matrix material followed by pyrolysis to form a fibrous C/C composite has been discussed. The processing of carbon paper has been divided into four steps, with the product of each stage used separately for different energy applications. (1) Carbon fiber preform has been used as a filler to achieve high strength in bipolar plates for PEM Fuel cells (energy conversion). Flexural strength of nearly 80 MPa has been achieved as compared to 40 MPa of the commercially available Schunk plate, Germany. (2) Resin impregnated preform, i.e. the Green composite paper has been employed as an energy efficient heating element (energy conservation). This has been further fabricated as a room heater, which works at <200 W of power as compared to 1–2 kW ingested by the commercial heaters. (3) The Carbonized paper, worked well as a free standing anode for rechargeable Li-ion batteries (energy storage). It delivers a discharge capacity of 225 mAh/g @ 0.2C rate with excellent cycling performance (>500 cycles). The (4) Graphitized carbon paper has proved to be an excellent electrode (anode and cathode) backing material for PEM Fuel cell. 25% hike in the peak power density of unit PEM FC has been achieved while employing CNT incorporated NPL carbon paper as compared to while using Toray carbon paper of Japan and tested under similar conditions. This in turn is attributed to the unique properties acquired by the material with subsequent processing at each stage which has been discussed in detail.

Core-shell Mn3O4 nanorods with porous Fe2O3 layer supported on graphene conductive nanosheets for high-performance lithium storage application

In this study, a core-shell nanostructure Fe2O3 coated grass-like Mn3O4 supported on graphene has been designed and fabricated via a facile and convenient hydrothermal method and thermal treatment routes. The Fe2O3 coated Mn3O4 nanorods with diameter of 35–40 nm are convolved by flexible graphene, which form a three-dimensional conductive network. As an anode for lithium-ion batteries, the as-prepared composite delivers an initial discharge/charge capacity of 1939.2/1393.5 mAh g−1 with a promising coulombic efficiency of 71.9% and a reversible specific capacity of 795.4 mA g−1 after 400 cycles at a high current density, which exhibits an upward trend in the capacity after long-term cycling as well. Both of the cross-linked structure and the synergistic effect are contributed to the enhance lithium-storage performance and dynamic characteristic, which reveals that the electrode holds a great potential as an anode material for rechargeable Li-ion batteries.

Enhanced electrochemical performance of Li3V1.5Al0.5(PO4)3-modified Li1.12(Ni0.18Co0.07Mn0.57)O2 cathode for Li-ion batteries

Li-rich manganese-based cathode materials are very promising for rechargeable Li-ion batteries. In our task, the Li-rich layered oxides Li1.12(Ni0.18Co0.07Mn0.57)O2 (LLMO) are prepared via the method of co-precipitation and solid-state reaction. Li3V1.5Al0.5(PO4)3 (LVAP) is applied to modify the LLMO by the chemical deposition method. Successful coating of LVAP layer on the pristine LLMO surface is demonstrated by TEM and XPS. Notably, the initial coulombic efficiency of LVAP-modified LLMO is 93%, which is improved compared to 82% of the pristine LLMO. The modified electrode also achieves excellent cyclic stability, which retains 96% of capacity after 100 cycles while the pristine electrode only retains 75%. Moreover, in comparison to the 100 mAh g−1 capacity of pristine LLMO at 5C, the LVAP-modified LLMO provides a high discharge capacity of 176 mAh g−1. In conclusion, this paper has demonstrated that the surface modification with LVAP is dedicated to improving the cyclic performance and rate capability of Li-rich layered oxides.

Superior Electrochemical Performance of Thin-Film Thermoplastic Elastomer-Coated SnSb as an Anode for Li-ion Batteries

The high failure strain of thermoplastic elastomers (TPEs) is a very desirable feature for rechargeable Li-ion batteries by improving the lifetime of high specific capacity anode materials that undergo mechanical fractures induced by large volume variations. In this work, poly(styrene-b-2-hydroxyethyl acrylate) called PS-b-PHEA was synthesized by a nitroxide meditated polymerization method. Owing to the use of a specific polystyrene macroinitiator (SG1), a suitable TPE copolymer with long hydroxyethyl acrylate blocks to ensure good mechanical properties is obtained for the first time. We show that the electrochemical properties of the PS-b-PHEA-coated SnSb anode are drastically improved by suppressing the crack formation at the surface of the electrode. Indeed, electrochemical characterization revealed that a high and stable gravimetric capacity over 100 cycles could be achieved. Moreover, excellent capacity reversibility was achieved when cycled at multiple C-rates and fast kinetics confirming the strong protection role of the polymer. The advanced chemical and mechanical properties of PS-b-PHEA open up promising perspectives to significantly improve the electrochemical performance of all electrodes that are known to suffer from large volume variations.

Nanoporous SiO coated amorphous silicon anode material with robust mechanical behavior for high-performance rechargeable Li-ion batteries

Silicon is a promising anode material for rechargeable Li-ion battery (LIB) due to its high energy density and relatively low operating voltage. However, silicon based electrodes suffer from rapid capacity degradation during electrochemical cycling. The capacity decay is predominantly caused by (i) cracking due to large volume variations during lithium insertion/extraction and (ii) surface degradation due to excessive solid electrolyte interface (SEI) formation. In this work, we demonstrate that coating of a-Si thin film with a Li-active, nanoporous SiOx layer can result in exceptional electrochemical performance in Li-ion battery. The SiOx layer provides improved cracking resistance to the thin film and prevent the active material loss due to excessive SEI formation, benefiting the electrode cycling stability. Half-cell experiments using this anode material show an initial reversible capacity of 2173 mAh g1 with an excellent coulombic efficiency of 90.9%. Furthermore, the electrode shows remarkable capacity retention of ~97% after 100 cycles at C/2 charging rate. The proposed anode architecture is free from Liinactive binders and conductive additives and provides mechanical stability during the charge/discharge process.

Crystal chemistry and lithium-ion intercalation properties of lithium manganese silicate cathode for aqueous rechargeable Li-ion batteries

Lithium manganese silicate (Li2MnSiO4) demonstrates rich polymorphism with orthorhombic Pmn21 polymorph having better crystalline ordering over orthorhombic Pmnb and monoclinic forms. In this work, Li2MnSiO4 nanoparticles with the Pmn21 phase were synthesized by hydrothermal synthesis. Powder X-ray diffraction, HRSEM, and HRTEM as well as SAXS investigations revealed crystalline, spherical nanoparticles with average diameters between 14 and 25 nm. The binding energy of surface active Mn2+ ions in Li2MnSiO4 was observed at 642.9 eV in XPS analysis. SSNMR spectroscopic results revealed isotropic peaks at − 288.5 and 295.32 ppm which are attributed to the hyperfine coupling between the Li nuclei and the unpaired electrons of the Mn2+ ions. The electrochemical properties of Li2MnSiO4 electrode were studied in various 1 M LiX (X = SO42−, NO3− and ClO4−) aqueous electrolytes at a potential window of 0.2–1 V. Studies in the Li2SO4 aqueous electrolyte demonstrated better electrochemical properties with increasing peak current values up till the 2000th cycle. Charge and discharge capacities of 77.0 and 57.7 mAh g−1 were obtained at a scan rate of 5 mV s−1 with a Li-ion diffusion coefficient of 1.61 × 10−16 cm2 s−2. A small charge transfer resistance in the Li2SO4 electrolyte was also observed in EIS measurements indicating faster charge transfer kinetics. An aqueous Li-ion Swagelok-type full cell was assembled with microcrystalline graphite as anode and Li2MnSiO4 as the cathode. 1 M Li2SO4 was used as the electrolyte. The cell delivered a charge capacity of 61.8 mAh g−1 and a discharge capacity of 52.5 mAh g−1 at a current load of 1.2 A g−1 with good capacity retention of 94.0% and a Coulombic efficiency of 99.5% over 3300 cycles. SEM image, FTIR, XPS, and discharge capacity versus coulombic efficiency plots of Li2MnSiO4 nanoparticles

Advanced Characterization Tools for Probing Anionic Redox in Layered Cathode Materials

Rechargeable Li-ion batteries with higher energy density are in urgent demand to address the global challenge of energy storage. In comparison with anode materials, the relatively low capacity of cathode oxides, which exhibit classical cationic redox activity, has become one of the major bottlenecks to reach higher energy density. Recently, anionic activity, such as oxygen redox reaction, has been discovered in the electrochemical processes, providing extra reversible capacity for certain transition-metal oxides. Consequently, a more complete understanding and precise controlling on anionic electrochemical activity in these high-capacity oxides have become a flourishing, yet challenging subject. Compared to TM cations, oxygen anion electrochemical activity is more challenging to experimentally prove and quantify for the following reasons: First, oxygen participates in the electrochemical activity at highly charged states when the partially delithiated oxides are typically very sensitive to high energy electron beam or X-ray source exposure. Second, peroxo-like species and O-holes resulted from oxygen oxidation are extremely reactive and unstable in air and carbonate based liquid electrolytes. Third, M(nd)−O(np) metal−ligand hybridization and rehybridization make it intricate to quantify and differentiate cation and anion contributions to electronic structure changes as well as their contributions to the extra capacity. Based on the above considerations, a multimodal characterization approach must be established for oxygen anion electrochemical activity. Here, we select Li1.2Mn0.54Co0.13Ni0.13O2 as the model compound and systematically study its structure response to the oxygen redox activity by combing neutron pair distribution function, X-ray absorption spectrum, resonant inelastic X-ray scattering and DFT calculation. An obviously increased short O-O pairs accompanying oxygen redox reactions is for the first time detected, and which should be ascribed to the shrink of the interlayer O-O distance. Also, theoretical analysis indicates that the selective decrease of O-O distance is originated from the different oxygen chemical coordination environment. Further, a coupling relationship between the oxygen redox and transitions metals migration is experimentally demonstrated, which reveals the structural origin of the stable lattice oxygen redox reactions. Based on these understandings in our work, an optimization guidance for anionic acitvity is unambiguously presented: designing a robust layered structure with high-covalency TMs while constructing a flexible local structure with high-ionicity TMs to achieve the reversible high energy density. Figure 1

Pushing the Limit of Layered Cathodes for High-Energy Density, Long-Term Cycling, and High Thermal Stability Rechargeable Li Ion Batteries

Development of advanced high energy density lithium ion batteries is important for promoting electromobility. Making electric vehicles attractive and competitive compared to conventional automobiles depends on the availability of reliable, safe, high power, and highly energetic batteries whose components are abundant and cost effective. Nickel rich Li[NixCoyMn1-x-y]O2 layered cathode materials (x > 0.5) are of interest because they can provide very high specific capacity without pushing charging potentials to levels that oxidize the electrolyte solutions. However, these cathode materials suffer from stability problems. We discovered that doping these materials with tungsten (1 mol%) remarkably increases their stability due to a partial layered to cubic (rock salt) phase transition. We demonstrate herein highly stable Li ion battery prototypes consisting of tungsten-stabilized Ni rich cathode materials (x > 0.9) with specific capacities > 220 mAh g-1. This development can increase the energy density of Li ion batteries more than 30% above the state of the art without compromising durability. R. Dahn, U. von Sacken, M. W. Juzkow, and H. Al-Janaby, J. Electrochem. Soc., 1991, 138, 2207.-U. Woo, B.-C. Park, C. S. Yoon, S.-T. Myung, J. Prakash, and Y.-K. Sun, J. Electrochem. Soc., 2007, 154, A649.H. Lee, C. S. Yoon, J.-Y. Hwang, S.-J. Kim. F. Maglia, P. Lamp, S.-T. Myung, and Y.-K. Sun, Energy Environ. Sci., 2016, 9, 2152.Watanabe, M. Kinoshita, T. Hosokawa, K. Morigaki, and K. Nakura, J. Power Sources, 2014, 258, 210.

A Highly Reversible 5V-Class Li2CoPO4f/Graphite Battery

Introduction To increase the energy density of the Li-ion rechargeable batteries, a use of high-voltage cathode materials as well as their stable operating systems are of importance. However, the issues represented by degradation of the cathode materials, electrolytes, and other cell components have obstructed the development of a high-voltage system over past decade. Here, we report that concentrated LiBF4 in a mixed solvents, propylene carbonate (PC) and fluoroethylene carbonate (FEC), allows a stable cycling 5 V-class Li2CoPO4F/graphite full-cell for more than 600 cycles. In the presentation, the optimized cell components with special attention to the compatibility between the carbon conductive agents and electrolytes, will be discussed. Method The LiBF4-based electrolytes were prepared by mixing a certain amount of salt with solvents in an Ar-filled glove box. The Raman measurement was conducted to study the solution structure of the electrolytes. The linear sweep voltammetric (LSV) was performed to evaluate the anodic limits of the electrolytes with three-electrode cells consisting a Pt plate as a working electrode and Li metals as reference and counter electrodes. The carbon compatibility with the electrolytes was estimated using cyclic voltammetric (CV) with two-electrode cells of carbon electrode and Li metal. The transition metals deposited on the cycled graphite electrodes in the LCPF/graphite full-cells after charge and discharge test were analyzed by an Energy-dispersive X-ray spectroscopy (EDS). Results As a result of LSV measurement, the anodic current started to flow from 5.8 V (vs. Li/Li+) in the concentrated 1:1.8 LiBF4:PC/FEC (5/5,n/n), which was far higher than that in the commercial electrolyte of 1M LiPF6 EC/DMC (1/1,v/v). The Raman spectroscopy analysis presented that the concentrated LiBF4 PC/FEC electrolyte had an aggregate (AGG)-predominant solution structure. An upshift of bands corresponding to the anion and free solvent molecules was observed with an increase of salt concentration, denoting strengthened coordination of anion and solvents with Li+. Therefore, it was considered that the highest occupied molecular orbital (HOMO) level of the anion and solvents was decreased since the Li+ ion functioned as a strong Lewis acid that resulted in partial electron donation from the anion and solvents to the Li+ ion. Moreover, it was revealed that the main causes of cell deterioration at a high potential were (i) decomposition of electrolyte, (ii) anion intercalation into the carbon additives, and (iii) transition metal dissolution from cathode material. Especially, the carbon conductive agents with a low graphitization degree was selected to increase carbon compatibility with the electrolyte. It was because the anion intercalation occurred easily to the carbon additives with a high graphitization degree, leading to the damage of the graphene layers by continuously exposing the sites where were highly reactive with the electrolyte. Also, it was obvious that an intensified coordination between the anion and Li+ in the highly concentrated electrolyte helped to impede the anion intercalation reaction. The concentrated LiBF4 PC/FEC electrolyte and the optimized cell design including carbon conductive agents with a low graphitization degree were applied to a 5 V-class Li2CoPO4F/graphite system. As a result, a stable charge and discharge for more than 600 cycles was obtained. Besides, it was revealed that the concentrated electrolyte contributed to the stable operation of the high voltage battery by suppressing the transition metal dissolution from the cathodes. In conclusion, on the basis of the various design factors as noted above; (i) improvement of oxidation stability, (ii) impeding the anion intercalation, and (iii) suppression of transition metal dissolution, we succeed to obtain a stable reversible operation of the 5 V-class Li2CoPO4F/graphite full-cell for the first time. Figure 1

(Invited) Identification of Cathode Materials for Ca Batteries

In the last years, concerns on Li availability have aroused the search for suitable alternatives to rechargeable Li-ion batteries. An attractive alternative is to combine sustainability with prospects of high energy density and develop metal anode technologies based on multivalent abundant elements such as Ca. The development of the Ca-ion technology requires technical advances to overcome the existing hurdles concerning electrolytes, electrodes and cell design1-3. Identifying cathode materials enabling effective diffusion of Ca2+ ions is far from being evident and, to the date, none of the investigated materials develops a stable high specific capacity with cycling 1-3. In order to identify potential cathode materials for the Ca batteries, we have carried out a Density Functional Theory investigation to quickly screen a variety of structures and compositions. The screening started with a pre-selection of candidate compounds from the Inorganic Crystal Structure Database (ICSD). For the selected compounds, the general strategy is firstly to calculate average voltage and volume changes associated to the redox reaction. In a second step, DFT calculations for the promising materials are performed to gain information of electronic and ionic conductivities, crystal structure of reduced/oxidized phases and possible phase transformations. Fifty Ca-transition metal compounds including oxides, sulphides, nitrides, carbonates and phosphates were preselected from the ICSD. Out of this set, 25 ternary oxides and the minerals belonging to the pyroxene, garnet and double carbonates groups have been analysed in deep. The results will be discussed in this communication. Acknowledgments: Authors are grateful for financial support from European Union H2020-FETOPEN funded project CARBAT-766617.

Lithium Imide (Li2NH) as a Solid-State Electrolyte for Electrochemical Energy Storage Applications

We here report the prospect of lithium imide, Li2NH, as a solid-state electrolyte for the rechargeable Li-ion battery. Our study reveals that the ionic conductivity in Li2NH is greatly improved by the cation and anion ordering, which is a gradual process that is initiated by Li-filling in the LiNH2 lattice (forming nonstoichiometric Li1+xNH2−x) and sequentially forms the orthorhombic α-Li2NH (lower structural ordering) followed by the cubic β-Li2NH (higher structural ordering). The process, thus, enables synchronization between the cation and anion dynamics in β-Li2NH making this Li2NH phase as one of the fastest Li-ion conducting lightweight ionic alkaline hydrides. Our study also indicates high electrochemical stability for the Li/Li2NH interface in β-Li2NH contradicting the existing perception. The study may aid the existing research in developing a cost-effective commercial Li superionic conductor with high electrochemical and thermal stabilities and high energy density at room- to moderate-temperature.

Battery Charger Prototype Design for Tire Pressure Sensor Battery Recharging.

One of the important devices in a vehicle is the tire pressure sensor. This device couples with other instruments inside the vehicle assisting the drivers in knowing the correct information about their vehicle’s tire pressure. This information helps improve vehicle handling, increases gas mileage, and extends tire lifespan. Once mounted inside the tire, the tire pressure sensor is a stand-alone device. It is powered by a battery that has a limited operating life. Due to it being mounted inside the tire, the driver does not frequently check tire pressure sensor battery. If the battery runs out, battery replacement is not an effective option. This work presents a battery charging prototype that recharges the tire pressure sensor battery. The developed device uses electromagnetic principles to wirelessly transmit power to a device that needs power. We designed a prototype and conducted some laboratory scale experiments. Experimental and validation were based on a tire pressure sensor developed by Kenda Rubber Ind. Co., Ltd, Taiwan (R.O.C). This tire pressure sensor consumes power from a 4.8 V 700 mAh Li-ion rechargeable battery. The experimental results show that the prototype can transmit 4.9 V induction voltage. The maximum current is up to 850 mA with the optimum transmission distance at around of 1.5 cm. This prototype recharges the tire pressure sensor battery wirelessly to extend its battery-power life.

A concise review on the advancement of anode materials for Li-ion batteries

Li-ion battery research absolutely focused on advancements in the production, optimization, and characterization of electrode materials. Novel materials are developed using different synthesis techniques to improve the physical properties in the Li-ion battery research. Morphological aspects of electrode materials played a key role in the Li-ion battery research via Nano technology. Amazing change in reactivity towards lithium is estimated once the particle size is decreased to nanometer level. The comprehensive explanation on modern information of novel materials as anodes for rechargeable Li ion batteries will be presented in this review.

Intercalation chemistry of graphite: alkali metal ions and beyond.

Reversibly intercalating ions into host materials for electrochemical energy storage is the essence of the working principle of rocking-chair type batteries. The most relevant example is the graphite anode for rechargeable Li-ion batteries which has been commercialized in 1991 and still represents the benchmark anode in Li-ion batteries 30 years later. Learning from past lessons on alkali metal intercalation in graphite, recent breakthroughs in sodium and potassium intercalation in graphite have been demonstrated for Na-ion batteries and K-ion batteries. Interestingly, some significant differences proved to exist for the intercalation of Na+ and K+ into graphite compared with the Li+ case. Such different host-guest interactions are unique depending on the host materials and electrolytes, which greatly contribute to a deeper understanding of intercalation-type electrode materials for next generation alkali metal ion batteries. This review summarizes significant advances from both experimental and theoretical calculations with a focus on comparing the intercalation of three alkali metal ions (Li+, Na+, K+) into graphite and aims to clarify the intimate host-guest relationships and the underlying mechanisms. New approaches developed to achieve favorable intercalation coupled with the challenges in this field are also discussed. We also extrapolate alkali metal ion intercalation in graphite to mono-/multi-valent ions in layered electrode materials, which will deepen the understanding of intercalation chemistry and provide guidance to explore new guests and hosts.

The Effect of Battery Separator Properties on Thermal Ramp, Overcharge and Short Circuiting of Rechargeable Li-Ion Batteries

Different types and thicknesses of commercially available separators have been studied for their impact on rechargeable lithium cell safety. We conducted the study by testing LiCoO2/graphite pouch cells fabricated with five different battery separator membranes- 16μm Al2O3-coated polyethylene (PE), 16μm polypropylene (PP), 16μm polyethylene (PE), 12μm polyethylene (PE) and 7μm polyethylene (PE). Cell safety was investigated by means of thermal ramp, overcharge, internal short circuit, and external short circuit tests. In addition, the physical properties of the separators were also characterized. The correlation between the material properties and the failure mechanisms of the battery cells were studied. It was found that separator thickness or cell energy density is not necessarily the key factor for every cell failure. Instead, other separator properties such as melt temperature, puncture resistance, dimensional stability, and shutdown feature play a more critical role in some cell failures.

Polymer of intrinsic microporosity-based macroporous membrane with high thermal stability as a Li-ion battery separator.

Polymers of intrinsic microporosity (PIMs) have numerous advantages such as good thermal stability (Tg > 300 °C) and mechanical stability (tensile strength at break > 60 MPa) as well as excellent electrical insulation performance and chemical/electrochemical stability. Herein, a macroporous membrane made up of a polymer of intrinsic microporosity (PIM-1) was fabricated and used as a separator of a rechargeable Li-ion battery for the first time. The PIM-1-based separator showed good thermal resistance with Tg > 300 °C, high electrolyte uptake, and excellent Li-ion conductivity.

Sur-/interfacial regulation in all-solid-state rechargeable Li-ion batteries based on inorganic solid-state electrolytes: advances and perspectives

Advances in sur-/interfacial regulation in all-solid-state rechargeable Li-ion batteries based on inorganic solid-state electrolytes are reviewed and promising perspectives are proposed.

Three-dimensional iron oxyfluoride/N-doped carbon hybrid nanocomposites as high-performance cathodes for rechargeable Li-ion batteries

Three-dimensional FeOF/NC hybrid nanocomposites have been successfully synthesized; the 3D nanocomposites exhibit improved electrochemical performances compared to bare FeOF.

Novel divalent organo-lithium salts with high electrochemical and thermal stability for aqueous rechargeable Li-Ion batteries

Novel electrolytes with wide electrochemical potential window and high thermal stability have great potential for aqueous rechargeable lithium-ion batteries (ARLBs). Herein, we report the synthesis of two ionic salts of lithium sulfonylbis(fluorosulfonyl)imide (LiSFSI) and lithium carbonylbis(fluorosulfonyl)imide (LiCFSI) with divalent Li+ for ARLBs. These ionic compounds are the derivatives of monovalent lithium bis(fluorosulfonyl)imide (LiFSI). The LiSFSI and LiCFSI exhibit the kinetic electrochemical stability window of ca. 3.78 and 3.52 V, respectively, which can be further expanded due to the formation of a stable solid electrolyte interface (SEI) layer. While LiFSI exhibits the kinetic electrochemical stability window of ca. 2.22 V without the formation of an SEI layer. Full ARLBs based on LiSFSI and LiCFSI electrolytes with a LiCoO2 cathode and graphite anode can deliver the specific discharge capacity of ca. 113.50 and 95.0 mAh/g, respectively, at 0.1C rate. Whereas, it is ca. 52.53 mAh/g for LiFSI at 0.1C rate. The capacity retention for LiSFSI, LiCFSI, and LiFSI based ARLBs are ca. 97.3, 89.6, and 67.8%, respectively, after 500 cycles. Furthermore, both LiSFSI and LiCFSI reveal much higher thermal stability compared to LiFSI. Thus, the derivatization of conventional ionic compounds is an effective strategy to enhance the battery performance and its lifetime.

Structural analysis of Al and Si substituted lithium germanium phosphate glass-ceramics using neutron and X-ray diffraction

Li2O-Al2O3-GeO2-P2O5 (LAGP) glass ceramics (GC) has potential for use as solid state electrolyte in Li-ion rechargeable batteries with better safety and thermal stability. In this work LAGP glass-ceramics with nominal composition of Li1.5Al0.5Ge1.5P2.9Si0.1O12, have been prepared and structural studies have been carried out to understand the effect of Al3+ and Si4+substitution in place of Ge4+ and P5+. Glass was prepared using melt quenching technique and converted into glass-ceramics by controlled heat treatment. We observed that the entire glass has changed in to crystalline form. Phase formation was confirmed using XRD (X-ray diffraction) and ND (Neutron diffraction). Rietveld refinement analysis was used for structural analysis using both ND and XRD data. Analysis showed better refinement in ND and the nuclear density information of two different positions of Li+ ion (M1&M2) was revealed from Fourier maps using ND data. This helps to predict the pathway of Li diffusion in the structural units and optimize the conductivity of material. Results showed expansion of c-axis and reduction of a-axis with substitution of Al3+ in place of Ge+4. Bottleneck for Li+ ion conduction found to increase making an easier path for conduction. The study was further correlated from the recorded local structural data using X-ray photoelectron spectroscopy and Raman Spectroscopy.