Browse Topic: Battery packs

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Application of DFSS for Optimizing Thermal Protection in Electric Vehicles during Battery Thermal Runaway Events2026-01-0142To be published on 04/07/2026
Battery thermal runaway is a major safety concern in electric vehicles because of the extreme heat and hazardous gases released during cell failure. These venting events can quickly raise the temperature of the battery enclosure and cabin floor, threatening occupant safety. To address this challenge, this study employs the Design for Six Sigma (DFSS) methodology to design and optimize a thermal protection system that delays and limits heat transfer to the cabin. A physics-based transient heat-transfer model was combined with DFSS principles to systematically evaluate insulation materials, shield layouts, surface emissivity, and layer geometry. An L-18 orthogonal array was used to identify key parameters and quantify their influence on thermal robustness. The optimized architecture reduced cabin-floor temperature rise under severe runaway conditions (600–900 °C vent gas), meeting occupant-egress safety requirements. Findings confirm DFSS as an effective framework for developing high
El-Sharkawy, Alaa, Asar, Mona, Taha, Nahla, Sheta, Mai
Proactive Fault Detection in EV Batteries Via Hybrid Method: Cell-to-Cell Variation Pattern and Physics-Based Model Insights2026-01-0391To be published on 04/07/2026
This study presents a distinct methodology for the early detection of faulty cells in electric vehicle (EV) battery systems, leveraging temporal voltage deviation patterns under real-world charging scenarios alongside outputs from a physics-based model. A comparative longitudinal analysis was conducted on a fleet of twelve EVs—six exhibiting stable performance and the other six demonstrating early-stage anomalies characterized by intermittent transitions from drive to neutral mode. These behavioral cues were investigated as precursors to deeper battery degradation. The analysis focused on cell-level voltage dispersion in battery pack during the mid-to-high state-of-charge (SoC) range (approx. 20–30% to full charge). Vehicles in healthy condition consistently displayed minimal voltage deviation between BMS-measured cell voltages and physics-based model predictions, whereas those with latent faults showed markedly higher variance, particularly between the highest battery and model
Jawle, Bharat Sanjay, Selvakumar, Ashwin, Puttoji Rao, Nagaraj Kumar
Modeling Non-Uniform Temperature Distribution in Lithium-Ion Batteries2026-01-0120To be published on 04/07/2026
Non-uniform temperature distribution within lithium-ion battery cells is a critical challenge that accelerates degradation, compromises safety, and reduces pack-level performance in electric vehicles (EVs). This work focuses on modeling and minimizing these thermal gradients through the structured optimization of a liquid-based Battery Thermal Management System (BTMS). A one-dimensional transient thermal model is developed to capture the axial temperature differentials (ΔT) in a cylindrical cell under dynamic drive-cycle loading, incorporating detailed heat transfer from the cell interior through thermal interface materials (TIM) and an aluminum cooling plate to the coolant. Using a Design for Six Sigma (DFSS) approach with an L18 orthogonal array, key control factors—including coolant flow rate, inlet temperature, TIM properties, and plate geometry—are systematically analyzed to identify configurations that optimally balance low average temperature with minimal internal temperature
El-Sharkawy, Alaa, Asar, Mona, Serpento, Stan, Sheta, Mai
CFD Modeling of Gas Formation and Venting During the EV’s Battery Cells Manufacturing Process2026-01-0384To be published on 04/07/2026
The battery is a critical component of electric vehicles (EVs), where high power demands pose significant operational challenges. One such challenge is gas generation within the porous anode layer, which can lead to pressure buildup inside the battery. The complex interfacial dynamics at the microscale play a crucial role in determining the effectiveness of gas venting and the resulting pressure evolution. This study examines the effect of gas generation at two different length scales on the pressure rise and bubble dynamics. First, gas generation within a representative anode microstructure sample is investigated using a Volume of Fluid (VOF) framework that resolves tortuous flow passages. The simulations reveal that gas generation in such microstructures can lead to pressure rises of several thousand Pascals, with interfacial behavior primarily governed by surface tension effects. Second, a high-level single-cell simulation is performed using a porous media approach to evaluate
Mahyawansi, Pratik J., Schlautman, Jeff, Viswanath, Priyanka, Srinivasan, Chiranth
Electrochemical-Thermal Simulation for Evaluating Indirect and Immersion Cooling in High-Power EV Charging2026-01-0403To be published on 04/07/2026
With the rapid advancement of electric vehicle (EV) fast charging technology, battery thermal management faces increasingly critical challenges due to elevated heat generation and stringent safety requirements. Conventional indirect cooling methods often struggle to provide sufficient heat removal under fast charging conditions, leading to potential safety risks. Immersion cooling has emerged as a promising solution because of its superior heat dissipation capability and uniform temperature distribution. In this study, an electrochemical-thermal coupled simulation framework is developed to evaluate indirect and immersion cooling performance under high-power charging conditions. A Pseudo-two-dimensional (P2D) electrochemical EV battery model is developed in GT-SUITE and validated against vehicle charging data. An immersion cooling system is also modeled and integrated into the battery framework to allow comparison with a conventional indirect cooling system under high-power DC fast
Guo, Yuyang, Rockstroh, Toby, Oezdag, Erdal, Haenel, Patrick, Bodemann, Basil, Toghyani, Somayeh
Novel Tube-in-Tube Steel Side Sill Reinforcement Design and Validation for Enhanced Crash Performance in EVs2026-01-0478To be published on 04/07/2026
Increased use of Electrical vehicles (EVs) brings in unique structural design challenges particularly in Side Impact scenarios when the battery pack positioned near the sill region elevates the possibility of battery penetration and thermal runway in crash event. Thus, Electric Vehicles require unique structural design solutions. This study focuses on a novel steel tube-in-tube Side Sill reinforcement design and its performance benefits over a traditional aluminum Side Sill reinforcement commonly used for battery protection in EV vehicles body components. The proposed Steel Side Sill design layout mainly focuses on structural rigidity and improved load transfer during side pole impact crash cases and addressing manufacturing complexity and cost reduction opportunity. Multiple Steel Side Sill reinforcement design iterations are carried out by finite element analysis with software like LSDYNA Hyper works [1]. The goal was to develop an optimal tubular design - maximizing load transfer
Kusnoorkar, Harsha, Khutorsky, Alex, Penumetsa, Vivek, Koraddi, Basavaraj
Simplified Thermal Runaway Propagation Modeling to Design a Mass Optimized Battery Pack2026-01-0404To be published on 04/07/2026
This paper presents a simplified approach to model thermal runaway propagation in a multi-cell battery pack, with the goal of designing a safe and lightweight pack for mass-sensitive applications. The key parameters which characterize single-cell thermal runaway, including heat release profile, apparent cell emissivity and mass loss, were extracted from empirical nail penetration tests. This characterization was used to drive a three-dimensional thermal model of a 19-cell hexagonal sub-pack with a center trigger cell. To enable rapid design exploration, a symmetry-based computationally simplified domain was used for a full-factorial Design of Experiments (DOE) varying cell spacing, epoxy thickness, heat spreader thickness, and cup geometry. The DOE results were used to identify dominant heat-transfer mechanisms, capture main and interaction effects, and determine mass-efficient design levers governing peak-neighbor cell temperature during propagation. Insights from the DOE study
Kalyankar, Apoorv, Owen, Elliot, Strohmaier, Kyle, Mardall, Joseph
Predictive Modeling and Sensitivity Analysis of Thermal Runaway in 800V Lithium-Ion Battery Module Using DFSS Methodology2026-01-0124To be published on 04/07/2026
Thermal runaway in high-voltage lithium-ion battery modules should focus on critical safety and design challenges in electric vehicle applications, which need predictive methods that enhance passenger safety and support regulatory compliance. The primary purpose of a lithium-ion battery in an electric vehicle is to provide reliable energy storage while maintaining safe operation under different operating conditions. This study proposes a Design for Six Sigma (DFSS) methodology to virtually predict and correlate thermal runaway and its propagation in an 800V high-power lithium-ion battery pack module. Conventional propagation analysis relies heavily on physical testing, whereas the DFSS-based virtual framework enables cost-effective evaluation at early design stages. Input factors included are heat transfer pathways, which are sensitive to the temperature changes, as well as thermal propagation time. Control factors are the design or process parameters that engineers use to establish
Dixit, Manish, Raja, Vinayak, Gudiyella, Soumya
Thermal Insulation Materials Used in Battery Pack Assembly: A Review of Materials, Test Methods, and Key Considerations2026-01-0406To be published on 04/07/2026
Electric vehicle (EV) battery packs have undergone substantial advancements in recent years, driven by engineering design improvements, material innovations, and increasingly stringent regulatory enforcement. These developments have enabled battery packs to become more energy-dense, which is essential for extending driving range and improving overall vehicle performance. However, with increased energy density comes a higher severity of thermal events, such as thermal runaway, which continues to raise concerns regarding vehicle safety, reliability, and long-term durability. This review highlights the critical role that thermal insulation materials play in mitigating the impact of such thermal events within EV battery systems. It presents an overview of commonly used thermal insulation materials, emphasizing their chemical composition, thermal resistance, and mechanical integrity under extreme conditions such as high temperatures and physical stress. The ability of these materials to
Ng, Sze-Sze, Dhyani, Abhishek, Gorin, Craig, Jeon, Junho, Nuguri, Sravya, Repollet Pedrosa, Milton, Rylski, Adrian, Shete, Abhishek, Steinbrecher, Jacob, Thomas, Ryan
Dual Battery Pack System for Multi-Voltage Electric Vehicle Operation2026-01-0392To be published on 04/07/2026
Electric Vehicles (EV) have become a major focus in the automotive industry. This paper introduces a propulsion system design, which supports the Wide Torque Band (WTB) concept to boost the power density of PM (permanent magnet) motors in EV Trucks resulting in performance, efficiency, and cost benefits. A selectable 400V/800V battery system has been developed to support the WTB concept and enhance the power density of permanent-magnet motors in electric vehicles. The RESS comprises two 400V battery packs that can be charged at 400V in parallel or at 800V in series via a DC fast-charging (DCFC) connection. In this study, an 800V driving mode was additionally implemented. A prototype battery management system (BMS) along with existing production voltage, current and temperature measurement block hardware are applied to perform mode switching, safety, and cell balancing. The success of this dual pack hardware enables high voltage dynamometer testing of a new 800V DU (Drive Unit) and
Zhu, Yongjie, Lee, Chunhao, Gopalakrishnan, Suresh, Namuduri, Chandra
A Dataset for Visual Classification of Battery Fire and Smoke2026-01-0569To be published on 04/07/2026
Battery fires pose a significant risk across a wide range of applications, including electric vehicles, consumer electronics, and grid-scale energy storage systems. Early detection of fire and smoke is critical to preventing catastrophic failures and ensuring human safety. In this study, we developed a synthetic dataset of battery fire and smoke images in the context of a simple battery pack. The primary application of this dataset is to support the development of a machine learning–based visual classification system capable of accurately detecting battery fires and smoke in real time at an early stage. The intended outcome is a deployable classification system that enhances battery safety through rapid visual identification of hazardous conditions.
Govilesh, Vidarshana, Gunasekaran, Aswin, Challa, Karthikeya, Maxim, Bruce, Shen, Jie
A Comprehensive Modelling Tool for Heavy-Duty Hybrid Fuel Cell/Battery Powertrains2026-01-0430To be published on 04/07/2026
The global transition towards sustainable transportation is driving the development of efficient, low-emission propulsion systems. Battery-electric solutions are effective in urban contexts, but face limitations in heavy-duty and long-haul applications due to the size and weight of the required energy storage. Hybrid battery/fuel cell powertrains offer a promising alternative for such use cases, reducing vehicle mass and charging times while maintaining high energy efficiency. This study presents an original zero-dimensional MATLAB/Simulink model, named HyPoST (Hydrogen Powertrain Simulation Tool), for a parallel hybrid fuel cell/battery system, here applied to heavy-duty vehicles. The model encompasses the main vehicle sub-systems, including the fuel cell stack with auxiliaries, battery pack, electric drive, transmission and the vehicle longitudinal dynamics, coordinated through a rule-based energy management strategy. Two representative heavy-duty vehicle configurations were analysed
Montecchi, Gianluca, Martoccia, Lorenzo, D'Adamo, Alessandro
Impedance Characterization of an Automotive Battery Pack2026-01-0381To be published on 04/07/2026
Parasitic inductance and capacitance of the battery pack can affect the performance of the electric powertrains. Characterizing these parasitic phenomena in an automotive battery pack is therefore crucial to ensuring performance and reliability. In this work, geometric models of a production automotive battery pack are developed to simulate the parasitic inductance of the busbar system, the parasitic inductance of individual modules, and other critical components. For these simulations, several assumptions and simplifications are introduced to reduce model complexity, while preserving the main electromagnetic behavior of the system. The impact of the different components on the battery pack impedance is investigated to evaluate parasitic capacitances, thereby simulating the worst-case scenario. Laboratory procedures are developed to accurately measure parasitic impedance, providing a reliable comparison between experimental data and analytical models and supporting the overall validity
Misley, Marco, D'Arpino, Matilde, Zhu, Di, Zhang, Liwen
Effects of Obstacle Height and Vehicle Roll Behavior on Electric Vehicle Side Impact Safety2026-01-0405To be published on 04/07/2026
Electric vehicles (EVs) face unique safety challenges under pole side impact conditions, largely due to the presence of floor-mounted battery packs. Existing regulatory test procedures, such as FMVSS 214, primarily address occupant injury using full-height cylindrical obstacles. These procedures were originally developed for internal combustion vehicles (ICVs). However, real-world roadside crashes frequently involve obstacles of varying heights, such as guardrails, curbs, and median bases. While these obstacles pose limited risk to the passenger compartment, they can intrude into the battery pack and trigger thermal runaway. This study investigates the influence of obstacle height on EV pole side impacts. Finite element simulations of a commercially available sedan were conducted against rigid obstacles of different heights. Results reveal a non-monotonic trend of battery intrusion governed by the interplay between rollover dynamics and structural stiffness. Theoretical analyses were
Ma, Chenghao, Xing, Bobin, Zhou, Qing, Xia, Yong
Electrified Propulsion System Balancing for Light Duty Full Size Truck and Sport Utility Vehicles: A 2026 North American Market Perspective2026-01-0412To be published on 04/07/2026
Achieving the stringent EPA CAFE 2032 standards for light-duty full-size trucks and sport-utility vehicles (SUVs) in North American poses significant challenges. While Battery Electric Vehicles (BEVs) offer a clear path to zero tailpipe emissions, their widespread adoption in this segment faces hurdles including range anxiety, payload/towing capabilities, and traditional truck/SUV use cases. This paper investigates a balanced approach, focusing on optimizing propulsion system design with appropriate hardware content, can effectively meet future fuel economy and emissions standards. This investigation examines advanced BEVs and hybrid electric vehicle architectures, including full hybrids (HEVs), and plug-in hybrids (PHEVs) tailored for full-size trucks and SUVs. Considerations include the optimal sizing of internal combustion engines, electric motors, and battery packs to deliver robust performance while maximizing energy efficiency. This paper analyzes the integration of technologies
Babcock, Dillon, Robinette, Darrell
Thermal Characterization of an Automotive High Voltage Junction Box2026-01-0390To be published on 04/07/2026
The high voltage battery junction box (HVJB) controls and protects the high voltage connections of the battery pack to the traction, auxiliary, and charging systems. HVJBs are composed of busbars, contactors, fuses, and other protection systems. The health of the HVJB is paramount to ensure performance of electric vehicles. However, sensing and monitoring in the HVJB are often lacking due to packaging cost, causing limited capability of the vehicle controller to estimate the status and health of the unit. This publication focuses on the experimentation of an automotive HVJB to characterize the operation and build the foundation for the development of prognostic algorithms for HVJB. A production HVJB has been acquired and heavily instrumented. Extensive testings are performed in adiabatic and in ambient conditions at various current levels for various durations of operation. The testing setup was calibrated and iterated based on preliminary results, and the testing conditions were
Arigo, Sam, Borgerson, Joe, D'Arpino, Matilde, Zhu, Di, Zhang, Liwen
Identifying Pressure Drop and Heat Transfer Correlations for a Liquid-Cooled Lithium-Ion Battery Pack Model of Electric Vehicles under Hot-Cold Driving2026-01-0394To be published on 04/07/2026
The performance of a full battery pack with its effective thermal management system (BTMS) depends on coolant flow and heat transfer characteristics inside the pack. To develop a full BTMS using model-based design (MBD), the model must capture the coolant pressure drop ∆?? and heat-exchange performance from the cell to ambient air via the coolant, cooling flow channels, air gaps, and pack cases. Predicting battery pack responses (i.e., voltage, SOC, temperature) under all weather conditions is a challenge, as a complete pack contains several hundred to thousands of cells, coolant lines, coolant line bends, and coolant channels. This work presents a detailed approach to identifying heat transfer and ∆P correlations that can capture the real-time thermal-electrical performance of a mass-produced LIB pack under constant speed (in winter) and transient driving (in summer). A vehicle test is conducted using a Tesla Model Y, 2-motor model equipped with a 75-kWh LIB pack. The LIB pack's
Sok, Ratnak, Kusaka, Jin
Physical Test Validated Multi-Level Power Electronics for Next-Generation Electrified Vehicles Charging & Efficiency Improvement2026-01-0435To be published on 04/07/2026
Improving the energy efficiency of electrified vehicles remains a central objective in modern electric powertrains. Multi-level converters (MLCs) are widely recognised for lowering conversion losses relative to two-level inverters and improving total harmonic distortion (THD) in the sinusoidal supply to motors with a consequent reduction in motor losses. Despite this, sustained production-oriented validation at the integrated system level remains limited. This work introduces a multi-level converter architecture of the Battery Integrated Modular Multi-Level Converter (BIMMC) topology using Cascaded H-Bridge (CHB) architecture. It offers improvements in all key metrics of performance, cost, package size, mass and robustness compared to the current state-of-the-art two-level inverter system with distributed functions for charging available in the market today. The overall solution is highly functionally integrated. It supports four major functions required in electric vehicles without
Bao, Ran, Kalaiselvan, Prashanth, Rener, Kristof, Hallam, Philip, Shi PhD, Kai, Yue, William, Ma, He, Grimshaw, Andrew, Patel, Simon
Mechanical Properties of Elastomeric Foam-Based Compression Pads for Battery Pack Applications2026-01-0247To be published on 04/07/2026
With the increasing adoption of electric vehicles (EVs) worldwide, ensuring the long-term reliability and performance of the battery systems has become a paramount engineering challenge. Lithium-ion cells exhibit dimensional changes throughout their operational life, characterized by reversible “breathing”—expansion and contraction during charge and discharge cycles—and irreversible swelling due to aging. Compression pads are critical components for ensuring the lifetime performance of battery packs. The primary function of a compression pad is to act as a compliant cushion between cells. It accommodates these volumetric fluctuations by exerting consistent and optimized pressure. By absorbing the stress from cell expansion and maintaining structural integrity within the module, compression pads mitigate degradation mechanisms and ultimately maximize the durability and safety of the battery system over thousands of cycles. This paper highlights the importance of tailoring elastomeric
Deng, Weilin, Gunashekar, Subhashini
Thermal Finite Element Modelling and Prediction of Laser Welded Battery Packs2026-01-0385To be published on 04/07/2026
Battery modules consist of battery cells electrically joined at the terminals by conductive busbars. Laser welds are the most consistent and controllable process to create these connections on a large scale due to their control over power, laser width, speed, wobble, and overlap, and their quality is critical to battery pack performance. Tuning these parameters for an application typically requires weld trials to reach desired weld width, penetration, and strength without overheating the battery cell and weakening the dielectric insulators around the terminals. Poorly welded cells in a module can result in increased electrical resistance, causing greater joule heating and accelerated cell aging, and poorly welded modules can lead to uneven aging and unpredictable performance. To better understand the laser welding process, a modelling approach was developed to predict weld properties to reduce production time, costs, and potential cell damage. The 3D finite element model was calibrated
Contreras, Luis, Hoffmeyer, Matthew, Abidin, Zainal
Standalone Battery Pack Thermal Behavior Simulation and Experimental Correlation in a Controlled Environment2026-01-0125To be published on 04/07/2026
Battery thermal management is crucial for ensuring the safety, efficiency, and longevity of lithium-ion battery packs, particularly in electric vehicles (EVs). The primary purpose of a lithium-ion battery in an electric vehicle is to store and provide electrical energy for vehicle propulsion while maintaining safety under different operating conditions. This work proposes a thermal correlation between 1D CFD simulation and experimental test data under passive environmental heat exchange conditions without active coolant flow of a battery pack comprising four modules. An environmental exchange test was conducted using a 50% state of charge (SOC) battery pack, which is stabilized at 25°C to assess passive heat dissipation, thermal soak behavior, temperature distribution, and potential thermal runaway risks. The simulation predictions correlate well within a 1.5°C range compared to test results using ambient temperature and flow inputs, which confirms the reliability of the modeling
Nayaka, Sateesh Kumar, Dixit, Manish, Gudiyella, Soumya
Embedded Real-Time Control of a Distributed Trailer Propulsion System with Regenerative Braking for Net Neutral Load Towing2026-01-0065To be published on 04/07/2026
Towing imposes substantial efficiency penalties on both battery-electric vehicles (BEVs) and internal combustion engine (ICE) vehicles, reducing range by 30-50%. This paper presents a proof-of-concept embedded control architecture for distributed trailer propulsion that actively regulates drawbar force to reduce towing loads. Unlike proprietary e-trailer systems requiring specialized hardware, the proposed implementation demonstrates feasibility using commercial off-the-shelf (COTS) components and open-source software. The distributed architecture employs dual Raspberry Pi 4B single-board computers communicating via ROS 2 at 20 Hz. The trailer-mounted controller executes a Simulink-generated control node coordinating load cell acquisition (HX711 ADC), motor CAN bus telemetry, and throttle commands to a 5 kW BLDC traction motor powered by a 5 kWh LiFePO4 battery pack. A vehicle-mounted controller logs OBD-II/CAN validation data. The control pipeline implements cascaded EWMA/Hampel
Joshi, Gaurav, Adelman, Ian, Liu, Jun, Donnaway, Ruthie
Understanding the Effects of Process Parameters on the Dispense Uniformity of Elastomeric Silicone Coating Material for Automotive Manufacturing.2026-01-0239To be published on 04/07/2026
As electric vehicle (EV) manufacturing scales, innovative approaches have been evolving for battery fire protection materials to mitigate thermal runaway hazards, including fire and blast protective coatings. These materials often exhibit high-viscosity and must be deposited with uniform thickness and stable geometry to ensure reliable thermal barriers and battery pack integration. In practice, coating uniformity (uniform thickness, edge fidelity, and minimal sag/run prior to cure) is highly sensitive to dispense conditions, including nozzle slot width, nozzle length, effective dispense height (stand‑off), nozzle sweep speed, and volumetric dispense rate. Establishing robust process understanding early is therefore essential to avoid start‑up scrap, rework, and variability downstream. This paper presents a combined computational and experimental methodology to optimize and de‑risk dispensing of elastomeric battery fire protection (BFP) coatings. We develop a physics‑informed modeling
Hossain, Arif, Repollet Pedrosa, Milton H., Norquest, Kade, Mcmichael, Jonathan, Ng, Sze-Sze, Aradhyula, Pranavi, Thomas, Ryan, Gorin, Craig, Dietsche, Laura, Kenney, James A.
The Study on Alternative Switching Noise Caused by Pulsating Magnetic Field Off Direct Current Ripple Induced by the Invertor Switching2026-01-50223/30/2026
As already well-understood/enormous engineering practices, the inverter AC-side NVH phenomena/mechanisms/measures for motor-equipped vehicle, are already pretty clear. In addition to inverter AC side–induced NVH issues, DC ripple induced by PE switching leads to NVH issues manifesting on the capacitor, inductor, and conductor in terms of reverse piezoelectricity, electrostriction, magnetostriction, Laplace force, and so forth. These DC-side NVH issues are already literally analyzed by a couple of literatures, and mechanisms/measures are explored/applied to electric drive development. And yet, the phenomenon that a pulsating magnetic field inside a battery pack induced by DC current ripple off PE switching brings noise at switching frequency inside the vehicle cabin is newly captured/analyzed by our research, and that has been barely searched during the literature survey. This newly discovered phenomenon is the pivotal point in this paper. Although the noise features like the
Zhao, Qian, Zhao, Yihan, Niu, Haolong, Li, Qiwei, Zhang, Wenchao, Xue, Hongbin, Cheng, Yanan, Li, Jing, Kang, Ming
Integrating Anti-Idle Power Systems into Military Tactical Vehicles: Use Case Development and Analysis2026-01-50203/11/2026
Military tactical vehicles are increasingly incorporating anti-idle kits as a method to reduce fuel consumption. The larger battery pack associated with the anti-idle kit has the potential to provide new capabilities to the warfighter, who can use the battery pack to power pieces of equipment. This study analyzes a set of these new capabilities derived from the U.S. Army Universal Task List, supplemented with user interviews and doctrinal analysis. These capabilities include powering dismounted soldier systems, counter-drone and surveillance equipment, mobile refrigeration for medical applications, field maintenance tools, and mobile food services. The study then uses geolocation data collected from the U.S. Army’s National Training Center to model daily fuel consumption for soldiers performing each of these activities. The model was subsequently adapted to incorporate an anti-idle kit, revealing significant reductions in fuel usage. The analysis uses the results to define common
Lusian, Trevonte, Mummert, Taige, Kaiser, Caleb, Greer, Michael, Black, Nathaniel, Ong, Bennett, Tapahonso, Eugene, Mittal, Vikram
Lithium Plating-Induced Surface Pressure Evolution in Lithium-Ion Pouch Cells under Rigid Constraints2026-01-70132/27/2026
In practical applications, power cells face a mix of external influences such as temperature variations and structural limits (rigid constraints) that trigger intricate electrochemical and mechanical reactions. This study systematically explores the temporal evolution of surface pressure in lithium-ion pouch cells subjected to rigid mechanical constraints under varying thermal conditions, with a specific focus on the interplay among mechanical stress, lithium intercalation, and lithium plating. To investigate the battery’s electrochemical and mechanical responses, this work integrates experimental measurements with an electrochemical–mechanical coupling model. The analysis is performed under initial loads of 0.3, 0.5, and 1.0 MPa at 25 °C (ambient temperature) and 0 °C (representative low-temperature condition). At 25 °C, surface pressure followed a two-stage pattern: first, stress relaxation occurred, followed by a shift into quasi-steady cycling (cycle-to-cycle variations are minimal
Du, Yingyue, Chen, Ying, Luan, Weiling, Chen, Haofeng
Regression of Quasi-Static and Dynamic Bottom Crush on Electric Vehicles Battery Pack Bottom Strike2026-01-70332/27/2026
Current studies about battery pack bottom strike usually focus on one test condition individually. To study the relation between quasi-static and dynamic crush in battery pack bottom strike, the paper combined quasi-static crush result and dynamic strike preset kinetic energy value with the same displacement damage on the battery pack bottom plate and cell. First, based on the finite element model of the battery pack, the quasi-static crush is applied. Several dynamic crush tests with different initial kinetic energy sets are also introduced. Then based on the same displacement damage, the pressure in quasi-static and kinetic energy in dynamic conditions are summarized. Fitting methods including polynomial regression, support vector regression (SVR), extreme learning machine (ELM), multilayer perceptron (MLP), Gaussian process regression (GPR), and K-nearest neighbor (KNN) regression are used to study the relation between the two different test load. The result shows that they have a
Tang, Hongxi, Wang, Shengwei, Zhou, Kai, Liu, Jinyu
Computational Study on Dynamic Handling Performance of a Retro Fitted Electric Two-Wheeler Using 125cc Powered ICE Reference2026-28-00472/12/2026
With the development in motor technology and battery technologies, the scope for a low-cost EV has been increasing in India. There remains an after-mark potential for conversion of an ICE powered two-wheeler to an EV power train. Such a move reduces the carbon footprint from the vehicle drastically and is still being explored. This study investigates the effect of replacing the ICE with an electric motor in a 125cc motorcycle, with a particular focus on vehicle handling performance using Slalom test. The two wheelers were modelled using calculated mass properties and estimated / calculated moments of inertia using CAD for both ICE and electric powertrains. The electric propulsion system took into consideration the role of a battery pack in the mass and MI calculation. The framework with degrees of freedom is well established in BIKESIMTM simulation environment. A slalom test with automatic gear shift and throttle to maintain speed of the vehicle was set-up to estimate the handling
Sankarasubramanian, Hariharan, M, Shaghasra, V, Ramprathap
Numerical Study of Battery Pack Cooling for Electric Vehicles2026-28-01102/12/2026
This study presents a systematic CFD-based investigation of air-cooled lithium-ion battery pack thermal management using a novel U-shaped channel. The U-shaped domain was selected due to its ability to promote recirculation and uniform air distribution, which enhances cooling effectiveness compared to conventional straight and Z-type channels. A systematic parametric optimization of inlet position and airflow velocity was performed to minimize hotspot formation and improve temperature uniformity. Results reveal that shifting the inlet from 30 mm to 20 mm and increasing velocity from 2 m/s to 3 m/s reduced the maximum battery temperature by 3.46 K, from a baseline of 333 K to 329.54 K, while maintaining minimal pressure drop. These findings highlight that strategic control of inlet parameters can yield significant thermal improvements with high cost-effectiveness and geometric simplicity.
PC, Murugan, J, Sivasankar, W, Beno Wincy, G, Arun Prasad
Galvanic Corrosion Susceptibility Analysis and Mitigation Strategies in Automotive Battery Packs2026-28-00182/12/2026
As electric vehicles continue to revolutionize transportation, ensuring the reliability of their powertrain systems and Battery Packs has become a critical focus. One key challenge is galvanic corrosion, which occurs when dissimilar metals in contact are exposed to an electrolyte, such as seashore moisture or road salt used in snow or ice zones. This corrosion can weaken structural components, compromise electrical conductivity, and reduce the lifespan of critical systems. Common areas at risk include metallic joints within battery enclosures, busbars, cooling systems, and electrical connectors. Environmental factors such as high humidity and temperature fluctuations further amplify the issue, making it a pressing concern for manufacturers. This paper aims to systematically identify critical galvanic joints within electric powertrain systems and Battery Packs and provide effective strategies to mitigate corrosion risks. Preventative measures include choosing compatible materials with
Narain, Aditya, Venugopal, Sivakumar, Gopalan, Vijaysankar, Varatharajan, Senthilkumaran
Performance Evaluation of a Novel Coolant Channel Configuration for Liquid Based Battery Thermal Management in Electric Vehicles2026-28-00422/12/2026
The performance and longevity of lithium-ion (Li-ion) batteries in electric vehicles (EVs) are critically dependent on effective thermal management. As internal heat generation during charge and discharge cycles can lead to uneven temperature distribution, exceeding optimal operating limits (25 - 40°C) can significantly degrade battery performance and lifespan. This study presents a performance evaluation of a novel liquid-based Battery Thermal Management System (BTMS) featuring a dual-directional coolant channel configuration designed to enhance thermal uniformity and heat dissipation. The proposed configuration combines horizontal and vertical coolant passages in an indirect cooling layout to address the limitations of conventional serpentine-type channels. A comprehensive thermal analysis was carried out under realistic loading conditions using three coolant types: water, ethylene glycol- based G48, and graphene-enhanced water nanofluids. These were evaluated for thermal
Selvan, Arul Mozhi, Periyasamy, Muthukumar, R, Thiruppathi, Prasad S, Hari, Raghav, R, Boddu, Sriram Pydi Aditya
Artificial Intelligence and Cloud Synergy for Scalable Battery Management Systems2026-28-01192/12/2026
Due to the rapid transformation of EVs and the battery storage system, the battery management system (BMS) is essential to ensure optimal performance of the battery storage piles. A BMS monitors and controls parameters such as SOC, voltage, current, and temperature. A traditional BMS has a minimum support of analytics, and it’s limited to local processing. However, when the battery information is uploaded to the internet, it becomes easier to manage maintenance and track the battery’s performance from anywhere in the world. This Cloud-based system is easy and made earlier, thereby giving a system alarm before the issue becomes big. Managing many batteries at once saves a significant amount of money in places like EV charging stations and Energy Storage Systems (BESS). Software updates to the system can also be sent remotely. Also, a BMS connected to the cloud can be used to support weaker grids in an instant if it needs the reactive power support. Cloud integration of BMS with the grid
R, Rajarajeswari, N, Kalaiarasi, Francis, Elgin Calister
Integrated Side Fairing and Crash Protection System for High Voltage EV Battery Safety2026-26-00281/16/2026
This paper presents a novel structural solution for side impact protection of high-voltage battery packs in electric trucks. While electric vehicles offer benefits like zero emissions and independence from fossil fuels, in turn present challenges in meeting crashworthiness standards and safety regulations. The device addresses the critical need for effective battery protection & styling of battery electric vehicles. The integration of a hybrid corrugated panel system with plastic side fairings is innovative, combining crashworthiness with aerodynamic and aesthetic benefits. The crash protection features two hat-section steel channels at the top and bottom and corrugated steel sheet with alternating ridges is attached to these channels. Corrugated panels are enforced with help of backing strips. This assembly is mounted on shear plates at both ends, secured to the vehicle's frame rail. During a side impact event, the plastic side fairings absorb the initial impact, crumpling easily. If
Badgujar, Prathamesh, Devendra, Awachare, Hansen, Benjamin
Development of Busbar with New Locking Mechanism for High Voltage EV Battery Applications2026-26-01551/16/2026
In the development of high-voltage (HV) batteries, ensuring secure connections between HV conductors and maintaining the safety and performance of the battery pack is paramount. Therefore, In the pursuit of enhancing efficiency and reliability in electrical connections, this paper explores the innovative alternate for a traditional screwing method with a friction locking mechanism for connecting busbars. The novel design reimagines the busbar as a Friction clamp (Female part) that securely holds the male part of the Busbar, significantly increasing the contact surface area up to 50%. This enhanced surface area not only improves electrical conductivity but also addresses heat generation issues associated with traditional screw-based connection. By eliminating the need for screws, the new design streamlines the assembly process, resulting in reduced cycle times and improved overall assembly line efficiency. This study presents the design methodology, performance analysis, and potential
Venkatesh, Murali, Raghu, Arun, Bhramanna, Amol
Analysis of Second-Life Electric Vehicle Batteries Value Maximizing through Repurposing and Resale, Ways to Achieve Optimal Performance and Standardization Challenges for Testing and Certification2026-26-01931/16/2026
As electric vehicle (EV) adoption accelerates globally, a growing volume of lithium-ion batteries are reaching an end-of-life in their primary automotive application—despite retaining 60 to 80% of their original capacity. This presents a significant opportunity to extend battery utility through second-life applications such as stationary energy storage, microgrid support, and commercial backup systems. This paper analyzes the strategies for maximizing the residual value of second-life EV batteries through repurposing and resale, while also addressing the challenges associated with performance optimization and standardization of testing and certification procedures. The study evaluates the techno-economic viability of second-life batteries compared to new systems, emphasizing cost savings, environmental impact, and emerging market demand. Techniques for enhancing second-life performance are examined, including advanced state-of-health (SOH) diagnostics, machine learning models for usage
Agarwal, Pranjal, Penta, Amar
Enhancing EV Battery Safety: Progressive Crushing and Energy Absorption Technique2026-26-01891/16/2026
A crash energy absorption technique and method improve the safety and structural integrity of electric vehicle battery packs during collisions, complying with global regulations. This analysis details an assembly featuring a battery housing for mounting battery cells, a crash member connected to the battery housing's periphery, and flexural members linked to the crash member. The flexural members are designed to absorb impact forces by deforming and storing potential energy during sudden impacts. This approach ensures energy is stored within the flexural elements and then transferred to the battery cells through progressive crushing. The design effectively delays intrusion, enhances battery safety, and minimizes cell-level damage. This solution improves occupant safety and prevents thermal runaway incidents while maintaining the battery's overall performance and reliability in EVs.
Amberkar S, Sunil, Lakshman singh, Meenakumari, Bodaindala, Anil Kumar
Dynamic Voltage EV System (DVEVS): Achieving Enhanced Electric Vehicle Efficiency and Performance through a Switchable Series-Parallel Battery Configuration2026-26-02031/16/2026
The electric vehicle (EV) industry is relentlessly pursuing advancements to enhance efficiency, extend driving range and improve overall performance. A notable limitation of conventional EVs is their fixed-voltage battery architecture, which necessitates compromises in powertrain design and can result in suboptimal efficiency under varying driving conditions. The Dynamic Voltage EV System (DVEVS) presents a transformative solution, allowing the battery pack to dynamically reconfigure its cells between series and parallel connections. This review explores the core principles of DVEVS, including battery topology, power-electronics-based switching, and the integration of hybrid energy storage solutions such as electric double-layer capacitors (EDLCs). We explore the foundational concepts of battery reconfiguration, delve into specific implementation strategies such as power-electronics-based switching and hybrid energy storage systems and address the critical need for adaptive thermal
Amberkar S, Sunil, Raool, Anuj Rajesh, M G, Shivanag, Rajapuram, Bheema Reddy
A Strategic Approach to the Selection of Switchgear and Busbars for EV Battery Packs2026-26-01651/16/2026
With the rising adoption of electric vehicles, the need for robust and efficient power distribution systems has become increasingly important. As the battery pack is the primary energy source for an electric vehicle (EV), the strategy of selection of switchgears and busbars is paramount. Currently, the design and selection of battery protection and conducting components, such as switchgears and busbars are carried out primarily focusing on the continuous current and the peak current capabilities of the battery pack. Despite this approach ensuring that the components can withstand extreme conditions, it often results in over-engineering. The sizing should be such that it does not overdesign, which would result in unnecessary cost and material weight addition to the pack, ultimately leading to performance deterioration. As the current discharge from a battery pack is dynamic in nature and fluctuates based on driving conditions and usage a real-time heat generation studies have to be
Soman, Anu, satheesh, Goutham, K, Mathankumar
A Comprehensive Analysis of Sealing Methods for EV Battery Packs - Trends and Insights2026-26-01801/16/2026
The widespread adoption of electric vehicles (EVs) has introduced distinct engineering challenges, particularly in the design of battery packs, which are crucial for vehicle performance, safety, and longevity. A critical requirement is maintaining ingress protection (IP) ratings of IP67 or higher to protect the high voltage battery packs against water and dust exposure. These ratings are crucial for ensuring compliance with homologation standards and meeting the demands of diverse terrains and operating conditions. Consequently, achieving effective sealing of EV battery packs is a fundamental aspect of their design and engineering. This study presents a comprehensive analysis of sealing technologies employed in EV battery packs, focusing on four primary types: adhesive-based sealants, Formed-In-Place Gaskets, foam cut seals, and rubber gaskets. Benchmarking data collected from over 100 vehicle models across more than 50 brands provides insights into adoption trends, historical shifts
Varambally, Vishakha, Sithick basha, Abubakker, Chalumuru, Madhu, Yaser, K U Syed, Sasikumar, K
Battery Thermal Management Approach for Two-Wheeler Electric Vehicles – An Indian Case Study2026-26-01511/16/2026
India's electric 2-wheeler (E2W) market has witnessed fast growth, driven by lucrative government policies. The two-wheeler segment dominates the Indian automotive market, accounting for the largest share of total sales. Consequently, the manufacturers of 2-wheelers are developing new electric vehicles (EV) tailored for the Indian market. However, the Indian EV market has witnessed multiple fire accidents in recent years, raising safety concerns among consumers and industry stakeholders. These incidents highlight key weakness in battery thermal management systems (BTMS), particularly during charging. Most existing E2W BTMS relies on passive (natural) air cooling, which has been associated with fire incidents due to its inefficiency in heat dissipation, particularly during charging in India's high-temperature environment. Therefore, it is imperative to build thermally viable and economical BTMS for the growing E2W vehicles with fast charging capability. FEV is actively developing the
Raut, Ankit, Hiremath, Vinodkumar S, Emran, Ashraf, Garg, Shivam, Berry, Sushil
Simplified Simulation of Electric Vehicle Battery Packs Using Deep Learning Based Reduced Order Models2026-26-04031/16/2026
The increasing adoption of electric vehicles (EVs), efficient and accurate battery modeling has become crucial for reliable performance evaluation and control system design. However, maintaining high accuracy in simulations generally requires complex computations, which can limit real-time applicability and scalability. High-fidelity battery models often require significant computational time, making them unsuitable for real-time simulations and large-scale system integration. This paper presents the application of Simulink Reduced Order Models (ROM) to simplify the simulation of EV batteries while maintaining acceptable levels of accuracy. The EV simulation environment has been developed in MATLAB/Simulink to analyze Battery Management System (BMS) control system design and assess EV system level performance. This simulation platform consists of BMS and other important EV controller models and high-fidelity plant models for battery and powertrain systems. While these high-fidelity
Vernekar, Kiran
Accelerating EV Thermal Controller Development Using Rapid Control Prototyping on Speedgoat2026-26-06851/16/2026
In the era of Software Defined Vehicles, the complexity and requirements of automotive systems have increased knowingly. EV Thermal management systems have become more complicated while having multiple functions and control strategies within software frameworks. This shift creates new challenges like increased development efforts and long lead time in creating an efficient thermal management system for Electric Vehicles (EV’s) due to battery charging and discharging cycles. For solving these challenges in the early stages of development makes it even more challenging due to the unavailability of key components such as fully developed ECU hardware, High voltage battery pack and the motor. To address this, a novel framework has been designed that combines virtual simulation with physical emulation at the same time, enabling the testing and validation of thermal control strategies without fully matured system and the ECU hardware. The framework uses the Speedgoat QNX machine as the
Chothave, Abhijeet, S, Bharathan, S, Ananth, Gangwar, Adarsh, Khan, Parvej, Gummadi, Gopakishore, Kumar, Dipesh
Driving Performance Impact Analysis on EV Components for Efficient, Safe, and Intelligent Mobility2026-26-06551/16/2026
Electric vehicles (EVs) are the cornerstone of sustainable transportation, but their performance and component longevity are heavily influenced by driving behaviors. This study proposes a comprehensive analytical framework to assess how different driving styles affect the operational health of key EV components such as the battery pack, motor, and DC-DC converter. Various driving styles such as aggressive, moderate, and economical are discriminated against using dynamic vehicle operation signatures including acceleration and braking intensity, turning profiles, and load variations. These behavioral patterns are reflected in the electrical responses, namely current and voltage waveforms across power electronic systems. By analyzing these electrical signatures, a range of KPIs can be estimated for each component, offering insights into their operational stress and degradation trends. Experimental analysis using real-time EV datasets validates the framework’s ability to predict and
Deole, Kaushik, Kumar, Pankaj, Hivarkar, Umesh
Performance Evaluation of Battery Pack With E-Rickshaw on Chassis Dynamometer by Using In-House Developed Driving Cycle2026-26-01481/16/2026
The present work highlights a case-study that aims to determine the performance (power input/output) and battery temperature on in-house developed e-rickshaw battery pack. With the rise of e-rickshaws in Indian market, the demand for the batteries have also increased and being the largest state-run energy company of India, R&D Centre of Indian Oil Corporation Limited (IOCL) has developed a chemically modified nanomaterial-based lead acid battery. The lab scale experiments, which are not presented in the study due to confidentiality and intellectual property obligations, indicated that the nanomaterial doped lead acid battery pack performs better than the control (reference) and leading commercial batteries in terms of lifecycle, capacity etc. Subsequently, this paper highlights the performance with IOC R&D Centre manufactured 12V/100AH chemically modified (nanomaterial) lead acid battery pack for e-rickshaw on duty cycle developed indigenously based on the city driving experiences. The
Saroj, Shyamsher, Sithananthan, M, Kumar, Prashant, Arora, Ajay, Sundaram, P, Kalita, Mrinmoy
Integrated Simulation of Electric Vehicle Model Using the ROM Approach2026-26-03691/16/2026
The growing demand for Electric Vehicles (EVs) has highlighted the importance of efficient and accurate simulation tools for design and performance optimization. The architecture of electric vehicles is distinct from that of internal combustion engine vehicles. It consists of on-board charger, DC-DC converter, Lithium ion battery pack, Inverter, electric motor, controllers and transmission. The battery pack supplies electric current to the traction motor, which then converts this electrical energy into mechanical energy, resulting in the rotational motion needed to drive the vehicle. Wide range of Multi-physics is involved in the simulation which involves Power electronics, Electromagnetics, Fluid Mechanics, Thermal engineering. This paper presents an integrated simulation and range prediction methodology for Electric Vehicles (EVs) using the Reduced Order Model (ROM) approach. The methodology includes simulation in both 3D and 1D domain. CFD simulation is performed to understand the
Shandilya, Anand, Kumar, Vivek
Optimizing Busbar Design by Investigating Critical Parameters and their Influence on Electrical and Thermal Behaviors for Reliable Electric Vehicle Battery Packs2026-26-04741/16/2026
With the rise of EVs, researchers are focusing on optimizing busbar design to meet the demands of high energy density, fast charging, and compact battery packs. The busbar design starts by selecting the material and the cross-sectional area required based on the rated current requirement. The width matches or may exceed the battery cell terminal size, whereas the length is optimized such that it is packaged within the given space constraints. The research also highlights the risk of busbars to oxidation and corrosion, which increases resistance and decreases conductivity for which plating/coating techniques are applied to improve the surface finish, overall durability, conductivity and in some cases the surface hardness, while minimizing the heat loss. Using simulations and experimental validation, the study examines three key design parameters: the weld diameter for busbar welded joints, electrical resistance, and contact resistance. A detailed analysis investigates how the weld
Nogdhe, Yogesh, Singh, Shobit Kumar, Paul, Jibin, Mishra, Mukesh, Menon, Praveen
Design and Validation of UDS Application Software for Fuel Cell Electric Vehicle within AUTOSAR Framework2026-26-02531/16/2026
Affordable and clean energy has been one of the major objectives adopted by United Nations under the 2030 Agenda for Sustainable Development. In this direction, fuel cell electric vehicles have gained popularity in recent times due their efficiency and environmental friendliness. Fundamentally, it uses compressed hydrogen from the vehicle-mounted tank and combines with ambient air to generate DC electricity. Water is created as a by-product and expelled through the tailpipe. The technology being integrated on powertrain architecture, along with battery pack can prove to be an efficacious approach for zero emission automotive system. However, hydrogen being the primary fuel, and being stored at high pressure, the system involves handling and potential hazards of hydrogen, and possibility of explosions due to hydrogen leaks. Hence, safety is the key issue in handling fuel cell vehicles. This paper discusses about role of Unified Diagnostic Services (UDS) in providing safety and
PRASAD, Dr. P SHAMBHU, Jacob, Joe, Hadke, Tanmay, Wagh, Priyanka, Achanur, Mallappa
Predictive Modelling of Battery Behaviour for Enhanced Energy Management in Electric Vehicles2026-26-03851/16/2026
The transition to electric vehicles is a significant change as the world moves toward sustainable objectives, and thus the effective usage of energy and batter functioning. However, accurate battery modelling and monitoring is still challenging due to its highly nonlinear behaviour because of its dependencies with temperature variations, aging effects, and variable load conditions. To address these complexities, there are smart battery management systems that monitor the key parameters like voltage, current, temperature, and State of Charge, ensuring safe and efficient battery operation. At the same time, this may not completely capture the battery's dynamic aging behaviour. Here, digital twin emerges as the powerful solution, which replicates the complete physical system into a virtual platform where we can monitor, predict and control. This research paper shows the digital twin solution framework developed for the real-time monitoring and prediction of key battery parameters and
G, Ayana, Gumma, Muralidhar
Optimisation-Driven Framework for Heterogeneous Battery-Pack Mixing in Fleet Applications2026-26-02091/16/2026
Fleet owners often encounter significant logistical and financial problems when dealing with battery packs of different ages and conditions. The standard industry practice is to replace old batteries with identical new ones. This process is inefficient because it costs a lot, creates too much inventory, and eliminates battery packs that are still useful too soon. The problem worsens when manufacturers stop making older battery models, which can force a vehicle to retire early. This paper puts forward a framework for mixing different types of battery packs to deliver the performance needed for a vehicle’s mission. We show how this works in three everyday service situations: 1) Repair, when a single damaged pack needs replacing; 2) Life Extension, where aged packs are combined with newer ones to meet mission range; and 3) Performance Restoration, which uses next-gen packs when the original parts are obsolete. The study shows that a vehicle can complete its required missions by
Nair, Sandeep R., Ravichandran, Balu Prashanth, Hallberg, Linus
State of Health Estimation Based on Dynamic Cell Behaviour in EVs2026-26-01831/16/2026
In electric vehicle (EV) applications, accurate estimation of State of Health (SOH) of lithium ion battery pack is critical for ensuring its performance, reliability, operational safety and user confidence. SOH is a key parameter monitored by Battery Management System (BMS) to check the remaining usable life of the battery and to make informed decisions regarding charging, discharging, power delivery, and maintenance scheduling. In traditional SOH estimation techniques commonly rely on simplistic full-cycle charge-discharge data or single-parameter tracking (such as voltage or internal resistance) and other method like coulomb counting. Kalman filter, model based method such as equivalent circuit modelling, data driven models etc. This methods not consider variable field conditions such as partial and full state of-charge usage condition, dynamic load profiles, and non-uniform aging. As a result, these methods can produce significant deviations in SOH estimation, potentially causing
Nikam, Ashish, Tiwari, Awanish Shankar, Sodha, Nirav, Hariyani, Ganesh, Ambhore, Yogesh Gajanan
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