Energy Storage Materials Research Articles

A Case Study of an Energy Barrier in Li-Ion Battery Cathode Material Using DFT and Post-HF Approaches.

With the ever-increasing interest toward energy storage materials, an accurate understanding of the underlying physicochemical processes becomes mandatory for enabling accurate and predictive simulations. In this study, we apply multilevel quantum chemical calculations on a benchmark material commonly adopted as a cathode in Lithium batteries, Li0.5Co0.5+3Ni0.5+4O2. We estimate the Lithium hopping barrier, a key quantity for the estimate of Li diffusion coefficient, at different levels: Hartree-Fock (HF), density functional theory (DFT), periodic local Møller-Plesset perturbation theory of second order, complemented with a coupled cluster correction evaluated using an embedded-fragment approach. The post-HF methods were used here not only for benchmarking the key quantities themselves but also for assessing the accuracy of different functionals and probing the influence of the long-range and static correlation. For the given system and quantity in question, we observe that obtained results do not significantly vary across different DFT functionals or post-HF methods, which is rather uncommon. Such an agreement between the employed methods suggests that static correlation, even if prominent in this system, cancels out in the studied energy differences. In fact, the values of the T1 diagnostics, which test the reliability of the single-reference description, do vary from one fragment to another. But for certain fragments they are fairly small and of similar magnitude, indicating the applicability of such fragments for the correction. Our best estimate of the reaction barrier is about 0.85 eV.

Progress and Perspective of High‐Entropy Strategy Applied in Layered Transition Metal Oxide Cathode Materials for High‐Energy and Long Cycle Life Sodium‐Ion Batteries

AbstractLayered transition metal oxide (LTMO) cathode materials of sodium‐ion batteries (SIBs) have shown great potential in large‐scale energy storage applications owing to their distinctive periodic layered structure and 2D ion diffusion channels. However, several challenges have hindered their widespread application, including phase transition complexities, interface instability, and susceptibility to air exposure. Fortunately, an impactful solution has emerged in the form of a high‐entropy doping strategy employed in energy storage research. Through the implementation of high‐entropy doping, LTMOs can overcome the aforementioned limitations, thereby elevating LTMO materials to a highly competitive and attractive option for next‐generation cathodes of SIBs. Thus, a comprehensive overview of the origins, definition, and characteristics of high‐entropy doping is provided. Additionally, the challenges associated with LTMOs in SIBs are explored, and discussed various modification methods to address these challenges. This review places significant emphasis on conducting a thorough analysis of the research advancements about high‐entropy LTMOs utilized in SIBs. Furthermore, a meticulous assessment of the future development trajectory is undertaken, heralding valuable research insights for the design and synthesis of advanced energy storage materials.

Deep Eutectic Solvent and Molten Salt-Assisted Construction of Wheat Straw-Derived N/O Co-Doped Porous Carbon for Flexible Zinc-Air Batteries.

As a common biomass resource, wheat straw is gradually being derived as carbon materials for oxygen reduction reaction (ORR) in zinc-air batteries (ZABs). Herein, the wheat straw-derived carbon was prepared by ball milling and pyrolysis using deep eutectic solvent (DES) as the medium, which avoided the cumbersome procedures. The hydrogen bond of DES was utilized to reconstructed into a hydrogen bond network structure between DES and lignin/cellulose/hemicellulose of wheat straw. The hydrogen bond network structure was converted into N/O co-doped porous carbon (N/O-WSPC) with abundant N/O co-doped sites after high-temperature pyrolysis. Meanwhile, KHCO3 was employed to further generate hierarchical pore structures and increase the specific surface area of the N/O-WSPC. The N/O co-doped sites provided intrinsic ORR activity, while the porous structure facilitates the mass transfer effect. Therefore, the N/O-WSPC exhibited a half-wave potential of 0.87 V (vs. RHE) and a limiting current density of 5.98 mA cm-2 for ORR. The N/O-WSPC-based flexible ZAB displayed an energy density of 652.23 Wh kg-1 and a charging-discharging cycle duration for over 19 h. The DES-assisted strategy facilitates the sustainable and efficient application of wheat straw-derived carbon materials in energy storage and conversion devices.

Effect of Confinement on the Structure-Conductivity Relationship in PEO/LiTFSI Electrolytes in 3D Microporous Scaffolds.

Because 3D batteries comprise solid polymer electrolytes (SPEs) confined to porous scaffolds with high surface areas, the interplay between polymer confinement and interfacial interactions on SPE total ionic conductivity must be understood. This paper investigates contributions to the structure-conductivity relationship in poly(ethylene oxide) (PEO)-lithium bis(trifluorosulfonylimide) (LiTFSI) complexes confined to microporous nickel scaffolds. For bulk and confined conditions, PEO crystallinity decreases as the salt concentration (Li+:EO (r) = 0.0125, 0.0167, 0.025, 0.05) increases. For pure PEO and all r values except 0.05, PEO crystallinity under confinement is lower than in the bulk, whereas the glass transition temperature remains statistically invariant. At 298 K (semicrystalline), total ionic conductivity under confinement is higher than in the bulk at r = 0.0167 but remains invariant at r = 0.05; however, at 350 K (amorphous), total ionic conductivity in confinement is lower than in the bulk for both salt concentrations. Time-of-flight secondary ion mass spectrometry indicates selective migration of ions toward the polymer-scaffold interface. In summary, for the 3D structure studied, polymer crystallinity, interfacial segregation, and tortuosity play important roles in determining total ionic conductivity and, ultimately, the emergence of 3D SPEs as energy storage materials.

How Do the Four Core Factors of High Entropy Affect the Electrochemical Properties of Energy-Storage Materials?

High-entropy materials (HEMs) are extremely popular for electrochemical energy storage nowadays. However, the detailed effects of four core factors of high entropy on the electrochemical properties of HEMs are still unclear. Here, a high-entropy La1/4Ce1/4Pr1/4Nd1/4Nb3O9 (HE-LaNb3O9) oxide is prepared through multiple rare-metal-ion substitution in LaNb3O9, and uses HE-LaNb3O9 as a model material to systematically study the effects of the four core factors of high entropy on electrochemical energy-storage materials. The high-entropy effect lowers the calcination temperature for obtaining pure HE-LaNb3O9. The lattice distortion in HE-LaNb3O9 leads to its decreased unit-cell-volume variations, which benefits its cyclability. Based on the restrained diffusion arising from the lattice distortion, the Li+ diffusivity of HE-LaNb3O9 at room temperature (25°C) is limited, which causes its lowered rate capability. However, the Li+ diffusivity of HE-LaNb3O9 at high temperature (60°C) becomes faster than that of LaNb3O9, which is attributed to the alleviated lattice distortion at the high-temperature, resulting in higher rate capability. The cocktail effects in HE-LaNb3O9 enable its larger electronic conductivity, better electrochemical activity, more intensive Nb5+ ↔ Nb3+ redox reaction, and larger reversible capacity. The insight gained here can provide a guide for the rational design of new HEMs with good energy-storage properties.

Bacterial Cellulose Applications in Electrochemical Energy Storage Devices.

Bacterial cellulose (BC) is produced via the fermentation of various microorganisms. It has an interconnected 3D porous network structure, strong water-locking ability, high mechanical strength, chemical stability, anti-shrinkage properties, renewability, biodegradability, and a low cost. BC-based materials and their derivatives have been utilized to fabricate advanced functional materials for electrochemical energy storage devices and flexible electronics. This review summarizes recent progress in the development of BC-related functional materials for electrochemical energy storage devices. The origin, components, and microstructure of BC are discussed, followed by the advantages of using BC in energy storage applications. Then, BC-related material design strategies in terms of solid electrolytes, binders, and separators, as well as BC-derived carbon nanofibers for electroactive materials are discussed. Finally, a short conclusion and outlook regarding current challenges and future research opportunities related to BC-based advanced functional materials for next-generation energy storage devices suggestions are proposed.

Transition Metal-Doped Layered Iron Vanadate (FeV3-xMxO9.2.6H2O, M = Co, Mn, Ni, and Zn) for Enhanced Energy Storage Properties

With its distinctive multiple electrochemical reaction, iron vanadate (FeV3O9.2.6H2O) is considered as a promising electrode material for energy storage. However, it has a relatively low practical specific capacitance. Therefore, using the low temperature sol–gel synthesis process, transition metal doping was used to enhance the electrochemical performance of layered structured FeV3O9.2.6H2O (FVO). According to this study, FVO doped with transition metals with larger interlayer spacing exhibited superior electrochemical performance than undoped FVO. The Mn-doped FVO electrode showed the highest specific capacitance and retention of 143 Fg−1 and 87%, respectively, while the undoped FVO showed 78 Fg−1 and 54%.

The extraction of inorganic phase-change materials from sugar industry wastes with the purpose of solid waste management

ABSTRACT This study focused on the feasibility of identifying and recycling inorganic phase-change materials (PCMs) from sugar industry wastes in two cities of Qazvin and Hamadan in Iran. In this study, dry sugar beet pomace, sugar beet pomace, sugar beet molasses, leaves and plant residues of sugar beet and sugarcane bagasse were investigated. The inorganic materials were identified by X-ray Diffraction (XRD), thermal characteristics were determined by differential scanning calorimetry (DSC), and morphological characteristics were determined by scanning electron microscopy (SEM). Additionally, physical and thermal properties of molasses and bagasse samples were analyzed to determine their suitability as inorganic PCMs. The results of this study demonstrated that molasses and bagasse have the potential to be used as mineral PCMs in thermal energy storage applications. The results of this study demonstrated that in the wet sugar beet pomace the highest and lowest concentrations of inorganic PCMs were silicon dioxide (SiO2) and sodium chloride (NaCl), respectively. Moreover, the highest calcium fluoride (CaF₂) composition was reported in dry sugar beet pomace. In the samples of leaves and residues of sugar beet and sugarcane bagasse, the highest concentration of was NaCl. The detection and recycling of mineral PCMs from sugar industry wastes offer a sustainable solution for waste management and provide a renewable source of thermal energy storage materials. Implication Statement This study demonstrated the potential for the extraction of inorganic phase-change materials from sugar industry wastes as a means of solid waste management. By repurposing these materials, we can reduce the environmental impact of sugar production and contribute to sustainable practices in the industry.

A Dual Effect Additive Modified Electrolyte Strategy to Improve the Electrochemical Performance of Zinc-Based Prussian Blue Analogs Energy Storage Device.

Prussian blue analogs (PBA) exhibit excellent potential for energy storage due to their unique three-dimensional open framework and abundant redox active sites. However, the dissolution of transition metal ions in water can compromise the structural integrity of PBAs, leading to significant issues such as low cycle life and capacity decay. To address these challenges, we proposed a dual-effect additive-modified electrolyte method to alleviate such issues, introducing sodium ferrocyanide (Na4Fe(CN)6) into aqueous alkaline electrolytes. It could not only capture Zn2+ dissolved on the surface of Na1.86Zn1.46[Fe(CN)6]0.87 (ZnHCF) electrode material during the cycling process but also conduct redox reactions on the electrode surface to provide additional capacitance. Through experiments and molecular simulation calculations, it showed that Na4Fe(CN)6 can restrict the movement of Zn dissolution into the electrolyte on the electrode surface. Based on this, an asymmetric supercapacitor based on ZnHCF//activated carbon was assembled with a modified electrolyte. The assembled supercapacitor displayed a specific capacitance of 1,329.65 mF cm-2, a power density of 2,900 mW cm-2, and an energy density of 388.28 mW h cm-2. This study provides a new idea for the design and construction of stable and efficient PBA energy storage materials by inhibiting the leaching of transition metals in PBA.

Enhancing electrode efficiency by tuning surface electronic properties and defects in NiFe layered double hydroxide nanosheets with Al or Zn cation vacancies

Layered double hydroxides (LDHs) containing transition metals have emerged as promising electrode materials for supercapacitors due to their low cost, strong redox activity, and environmental friendliness. In this study, we propose a novel approach by creating Zn-defect Zn(II) engineered D-NiFeZn-LDHs through cyclic voltammetry etching in an alkaline solution of NiFeZn-LDHs synthesized on a carbon cloth substrate. This defect engineering increases electrochemical active sites and improves ion diffusion within the layered structure. The D-NiFeZn-LDHs demonstrate an impressive specific capacitance of 1204.8 F g⁻1 at 1 A g⁻1 and retain 61.52 % of their initial capacity after 10,000 cycles at 10A g⁻1, showcasing excellent long-term cycling stability. Moreover, the all-solid-state asymmetric supercapacitor constructed using D-NiFeZn-LDHs delivers a high energy density of 31.63 Wh kg⁻1 at 125 W kg⁻1 and retains 65.95 % of its capacity after 5000 cycles at a high current density of 10 A g⁻1. These findings provide a new strategy for developing high-performance energy storage materials.

High-performance α-Fe2O3 nano cubes as anode for supercapacitors

Abundant availability, high theoretical specific capacitance and low cost of transition metal oxides such as iron oxides, make them attractive as electrode materials for energy storage. In order to achieve improved performance, high conductivity, shorter ion-diffusion path, and faster ion accessibility, rational design of morphology of electrode material is highly desirable. We have successfully synthesized mesoporous α-Fe2O3 nanocubes to achieve high specific capacitance and better retention. The as-prepared and annealed α-Fe2O3 nanocubes show high reversible redox activity along with good thermodynamic stability. These nanostructure give rise to high specific capacitance and ~90 % of the capacitance can be retained even after 1000 redox cycles, suggesting good cyclic stability. The electrochemical performance of mesoporous α-Fe2O3 nanocubes is attributed to the morphological features, which results in efficient K+ ion transport into the pores. A two electrode α-Fe2O3//NiO device is fabricated, which shows excellent power and energy density of ∼627 W/kg and ∼23.32 Wh/kg, respectively. Our work demonstrates that 3D nanoporous α-Fe2O3 electrodes forms promising material system as anode for improved charge storage performance.

Nanocellulose/metal-organic frameworks composites for advanced energy storage of electrodes and separators

Nanocellulose is widely utilized in various fields due to its high surface area, excellent mechanical strength, and environmental friendliness. However, nanocellulose is an insulating material with typically low electrical conductivity. Metal-organic frameworks (MOFs) are appealing because of their huge specific surface areas, highly flexible pore size and porosity, diverse topological structure, changeable surface chemistry, and good chemical and thermal strength. The high porosity and surface area, good electrical conductivity, excellent mechanical strength, and flexibility of nanocellulose/MOF composites (NC/MOFs) make it a promising material for energy storage. This paper provides a review of the synthesis and application of NC/MOFs for energy storage of electrodes and separators. It presents the physical and chemical properties of nanocellulose and MOF. Particularly, two preparation strategies for NC/MOFs, the in-situ synthesis method and the ex-situ blending method, are introduced. Then the applications of NC/MOFs in energy storage of electrodes and separators are delivered, including supercapacitors, lithium-ion batteries, sodium-ion batteries, and others. Finally, the challenges and prospects of NC/MOFs for energy storage are addressed.

Steering the reaction kinetics of the MgO-V2O5 system toward selective synthesis of magnesium vanadates

Magnesium vanadates (MgV2O6, Mg2V2O7 and Mg3V2O8) are common redox catalysts for organic reactions and excellent energy storage materials. However, due to the diversity of magnesium vanadates and their interconvertibility, it is difficult to accurately synthesize a species of magnesium vanadate or control its stability during functioning. Herein, the reaction kinetics of MgO-V2O5 system was studied for controllable synthesis of magnesium vanadates. The MgO-V2O5 diffusion couples were prepared to explore the interface reaction characteristics of the MgO-V2O5 system at different reaction time. During reaction, the thickness of the diffusion layer and diffusion coefficient gradually increased and reached a maximal value of 29.55 μm and 6.06×10-11 cm2·s−1 at 10 h, which diffusion is faster than that of CaO-V2O5 system. Additionally, the interconvertible mechanisms of different magnesium vanadates were investigated using XRD and SEM/EDS techniques. MgV2O6 was produced during the synthesis of Mg2V2O7 in the initial 4 h, which converted into Mg2V2O7 at a longer synthesis time. Mg2V2O7 was found during the generation process of Mg3V2O8; with abundant MgO, Mg2V2O7 converted into Mg3V2O8. These findings provide important insights into the accurate control of magnesium vanadate synthesis and even the vanadium extraction process.

Mn-Zr promoted CaCO3 porous microspheres for enhanced performance in direct solar-driven calcium looping

The Calcium looping thermochemical reaction directly driven by solar energy effectively addresses the problem of efficient energy storage of concentrated solar power plants (CSP) by shortening the energy conversion path. But new requirements are put forward for energy storage materials, including high solar radiation absorption, high cycling stability and fast kinetics. To meet these challenges, we have designed porous microsphere structures for the purpose of enhancing mass transfer and the capture of solar radiation. Additionally, Zr and Mn oxides with elevated Tammann temperatures were incorporated to stabilize the morphology and prevent sintering. The synthesized porous microspheres retained abundant mesoporous channels on the surface even after undergoing 20 cycles. The addition of Mn oxide significantly enhances solar spectral absorptivity, achieving an impressive 82.88 % absorbance. The incorporation of Mn and Zr oxides increased the sintering resistance, specific surface area and porosity of CaO/CaCO3, especially in the 10–100 nm range, which accelerated the CO2 transport during carbonation. These enhancements significantly improve the chemical control stage of the carbonation reaction, as further supported by kinetic models. After 50 cycle experiments at 800 °C, the energy storage density of the sample remains at 1074 kJ/kg, which is 1.86 times that of the undoped CaCO3. This study provides a new way to design CaCO3 materials suitable for CSP applications.

Amino Acid Supported Conductive Nanocomposite for Developing Flexible Electrode Material for Energy Storage

Introduction: This study focused on synthesizing biocompatible, flexible and wearable electrode materials for energy storage applications. The unique zwitterionic structure of L-proline provides numerous interesting properties to the nanocomposite such as high ionic interactions through the various ion migration channels, and strong hydration characteristics. These features are key to thehigh performance of energy deposition systems.Methods: Binary nanocomposites containing L-proline (Pro) amino acid and polypyrrole (Ppy) were produced on rGO modified carbon textile (rGO-CC) to develop electroactive materials. Two step hydrothermal method was used to produce flexible electrodes. DRIFT spectroscopy andAFM analysis were performed to clarify the structural and the morphological characterization. Electrochemical behavior was evaluated utilizing CV, GCD and EIS methods.Results: ProPpy@rGO-CC electrode materials exhibit high electrochemical performances in aqueous electrolytes (0.1 M NaCl). The prepared electrode shows high specific capacitance of 500.4 Fg-1 (at 25 mVs−1) at the ambient conditions. Additionally, after 5,000 charge/discharge cycles the specific capacitance retains a high level of 95% confirming the good cycle stability. The energy and the power densities were found to be 278 Wh kg−1 and 12.5 kW kg−1, respectively.Conclusion: The results indicate that the ProPpy@rGO-CC electrode is a promising candidate for next-generation high-performance energy deposition systems. The unique structural features of L-proline contribute to the formation of a large number of electroactive sites and short diffusion pathways.

Integration of renewable energy-powered cold storage solutions for reducing post-harvest food waste in rural agricultural areas

Post-harvest food loss remains a critical challenge in rural agricultural areas, exacerbated by inadequate storage facilities and unreliable energy access. This study develops and optimizes an advanced renewable energy-powered cold storage system tailored for rural settings, integrating solar and wind energy with phase change materials (PCMs) for efficient energy storage. The system incorporates Internet of Things (IoT)-based sensors and artificial intelligence (AI)-driven energy management to maintain optimal storage conditions and enhance energy efficiency. Field trials conducted in Lincolnshire, UK, and Appalachian regions of the US demonstrated significant reductions in post-harvest food loss by an average of 43.5%, extensions in produce shelf-life by up to 300%, and increased income for smallholder farmers by approximately 43%. The system also achieved an 80% reduction in greenhouse gas emissions compared to conventional diesel-powered systems. Economic analyses revealed a shorter payback period and higher return on investment, confirming the system's viability. High user satisfaction and adoption rates indicate the system's practicality and potential for widespread implementation. The findings suggest that integrating renewable energy with smart technologies in cold storage solutions offers a scalable and sustainable approach to enhancing food security, promoting economic growth in rural areas, and supporting environmental objectives globally.

Cell-Shearing Chemistry Directed Closed-Pore Regeneration in Biomass-Derived Hard Carbons for Ultrafast Sodium Storage.

The closed-pore structure of hard carbons holds the key to high plateau capacity and rapid diffusion kinetics when applied as sodium-ion battery (SIB) anodes. However, understanding and establishing the structure-electrochemistry relationship still remains a significant challenge. This work, for the first time, introduces an innovative deep eutectic solvent (DES) cell-shearing strategy to precisely tailor the cell structure of natural bamboo and consequently the closed-pore in its derived hard carbons. The DES shearing force effectively modifies the pore architecture by simultaneously shearing and dissolving amorphous components to form closed pore cores with adjustable sizes, as well as disintegrating crystalline cellulose through generation of competing hydrogen bonds to elaborately tune the pore wall thickness and ordering. The optimized closed-pore structure featuring appropriate pore size (∼2 nm) and ultra-thin (1-3 layers) disordered pore walls, exhibits abundant active sites and delivers rapid ion diffusion kinetics and high reaction reversibility. Consequently, a high reversible capacity of 422 mAh g-1 at 30 mA g-1 along with an exceptional rate capability (318.6 mAh g-1 at 6 A g-1) are achieved, outperforming almost all previous reported hard carbons. The new concept of cell-shearing chemistry for closed-pore regeneration significantly advances the applications of biomass materials for energy storage.

Hierarchical Flower Array NiCoOOH@CoLa‐LDH Nanosheets for High‐Performance Supercapacitor and Alkaline Zn Battery

AbstractNickel oxyhydroxide based energy storage materials have been largely confined by insufficient exposure of active sites which results in low energy efficiency and poor stability. In order to resolve the problems, hierarchical flower array heterostructure NiCoOOH@CoLa‐LDH (denoted as NC@CL) nanosheets are designed with NiCo oxyhydroxide (NiCoOOH, denoted as NC) being tightly covered on CoLa layered double hydroxide (CoLa‐LDH, denoted as CL) nanosheet. This rational design creates more active sites, enlarges the electrode‐electrolyte contact area, improves electron conductivity, and prevents agglomeration during the cycling charge–discharge processes. Density functional theory calculations and differential charges concurrently illustrate that heterostructure formation optimizes the reaction kinetics and promotes electron redistribution. Benefiting from the heterogeneous structure and rich electro‐active sites caused by NC, NC@CL displays outstanding reversible specific capacitance (3228 F g−1 at 1 A g−1). The aqueous rechargeable alkaline Zn battery NC@CL//Zn exhibits a high capacity of 381.1 mA h g−1 at 0.5 A g−1 and cycling durability (98% capacity retention after cycling at 5 A g−1 for 2000 cycles). The excellent electrochemical performances indicate that NC@CL has great application potential as electrode material for aqueous energy storage device.

Quantitative Design of Cathode Materials for Ion Battery from a Reductionist Perspective

AbstractThe quantitative design of functionalities for functional materials is highly attractive for materials research, which must be based on a thorough understanding of the behavior of fundamental particles. Reductionism advocates for the understanding of complex materials through dissection into the constituent parts, providing a robust framework for investigating functional materials. In an ion battery system, this review utilizes reductionism to deconstruct cathode materials into phase, atom, and even electron, building the intrinsic connections between the macroscopic properties and fundamental particles across four degrees of freedom. This aims to enable the quantitative design of cathode materials. Specifically, the microscopic origins of the macroscopic properties, that is, capacity, potential, rate, and cycling reversibility, based on lattice, charge, orbital, and spin degrees of freedom are elucidated. Additionally, current strategies are summarized and proposed future development directions for improving these properties. These insights contribute to achieving the goal of quantitative design of energy storage materials.

Use of Modified Organic and Inorganic Phase Change Materials for the Development of Personal Cooling Device

The human body needs comfort in every condition. Human health is significantly impacted by heat. The ambient air temperature rises in hot weather, which causes the human body to become fatigued and exhausted. Phase Change Materials (PCM) can solve this problem with high latent heat absorption values and a wide range of phase change temperatures. The objective is to develop a PCM-based cooling device that is safe, readily available, and easy to use in normal routine life. A personal cooling system, such as a cooling vest using PCM, can assist in preventing heat-related issues. In this study, Polyethylene Glycol-600 (PEG-600) and modified glauber salt are selected as thermal energy storage materials with melting temperatures of 18–22°C and 27°C, respectively. Graphene Oxide (GO) nanoparticles were synthesised and mixed into the PEG-600 to enhance its thermal conductivity and latent heat of fusion. GO nanoparticles were prepared by Modified Hummer’s method (MHM) and characterised by Fourier’s Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Scanning Electron Microscopy (SEM). The latent heats and melting ranges of GO/PEG-600 and modified glauber salt were investigated by Differential Scanning Calorimetry (DSC). The addition of 0.6 wt.% GO to PEG-600 results in an increase in thermal conductivity of 6.1% and latent heat of 8%. The PCMs are encapsulated in aluminium packs, sealed, and kept in a cooling device. The developed cooling vest provides cooling for up to 95 minutes. The cooling vest is recharged by keeping it below 10°C for 20 minutes. The developed personal cooling device provides a passive, inexpensive, and safe cooling system by extracting heat from the human body.