Browse Topic: Vehicle charging

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A Fault Prediction Model for Electric Vehicle Charging Equipment Based on Adaptive Dynamic Thresholds2025-01-8117To be published on 04/01/2025
The surge in electric vehicle usage has expanded the number of charging stations, intensifying demands on their operation and maintenance. Public charging stations, often exposed to harsh weather and unpredictable human factors, frequently encounter malfunctions requiring prompt attention. Current methods primarily employ data-driven approaches or rely on empirical expertise to establish warning thresholds for fault prediction. While these approaches are generally effective, the artificially fixed thresholds they employ for fault prediction limit adaptability and fall short in sensitivity to special scenarios, timings, locations, and types of faults, as well as in overall intelligence. This paper presents a novel fault prediction model for charging equipment that utilizes adaptive dynamic thresholds to enhance diagnostic accuracy and reliability. By integrating and quantifying Environmental Influence Factors (EF), Scenario Influence Factors (SF), Fault Severity Factors (FF), and
Wang, Hao, Wang, Ning, Li, Yuan, Tang, Xinyue
Technical Paper
Lithium battery health status and lifespan prediction based on deep learning2025-01-8126To be published on 04/01/2025
Rechargeable lithium batteries are widely used in the electric vehicle industry due to their long lifespan and high energy density. However, after long-term repeated charging and discharging, various electrochemical reactions inside lithium batteries can lead to performance degradation and even cause battery fires. Estimating the health status and predicting the remaining life of lithium batteries can provide insights into their future operating conditions, which is crucial for achieving fault warnings and ensuring the safe operation of battery-related equipment. In terms of predicting the health status of lithium batteries, this paper proposes a method based on an improved LSTM for health status estimation. This method first employs nearest neighbor component analysis to eliminate feature redundancy among the multidimensional health factors of the battery. Then, the differential grey wolf optimization algorithm is used to globally optimize the hyperparameters of the LSTM. The
K, meng zi
Technical Paper
A framework for modeling mechanically induced thermal runaway in lithium-ion batteries2025-01-8134To be published on 04/01/2025
Battery safety is a paramount concern in the development of electric vehicles (EVs), as failures can lead to catastrophic consequences, including fires and explosions. Ensuring the reliability and robustness of lithium-ion cells under various conditions is essential for the widespread adoption of EVs. With the rapid global adoption of EVs, understanding how battery cells perform under extreme conditions such as mechanical or thermal abuse is crucial for ensuring safety. This study investigates the dynamic behavior of lithium-ion pouch cells under mechanical abuse conditions, focusing on improving safety measures in EV battery systems. Our research systematically examines the response of these cells at different states of charge (SOC), through controlled dynamic tests. These tests, which involve varying strain rates and punch geometries, offer significant insights into the mechanical thresholds that lead to cell failure. By analyzing the data, we gain a deeper understanding of the
Patanwala, Huzefa, kong, Kevin, Challa, Vidyu, Darvish, Kurosh, Sahraei, Elham
Technical Paper
Reducing Temperature-related Aging Inhomogeneities in Battery Modules Using a Switchable Thermal Management System2025-01-8167To be published on 04/01/2025
The operating temperature of lithium-ion battery (LIB) cells significantly influences their degradation behavior. In indirect liquid cooling systems, temperature variations within a Battery Electric Vehicle (BEV) LIB module are inevitable due to the increasing downstream temperature of the cooling medium as it absorbs heat. This leads to reduced temperature differentials between the cooling medium and the LIB cells. As a result, LIB cells located further along the flow path experience higher average temperatures than those at the front. Typically, a maximum average cell temperature difference of 5 K within LIB modules is considered acceptable. However, results from a conventional cooling system indicate that, when fast charging is exclusively used, this can lead to a 15.5 % difference in the total ampere-hours passed before the End-of-Life (EOL) is reached for the front and back LIB cells. To address this issue, a switchable thermal management system for the traction battery is
Auch, Marcus, Weyershäuser, Konstantin, Kuthada, Timo, Wagner, Andreas
Technical Paper
Development of Ceramic Humidity Regulator (CHR) Using Honeycomb Type PTC Heater to Improve Electric Vehicle Driving Range in Winter2025-01-8177To be published on 04/01/2025
With Rapid growth of Electric Vehicles (EVs) in the market, challenges such as driving range, charging infrastructure, and reducing charging time needs to be addressed. Unlike traditional Internal combustion vehicles, EVs have limited heating sources and primarily uses electricity from the running battery, which reduces driving range. Additionally, during winter operation, it is necessary to prevent window fogging to ensure better visibility, which requires introducing cold outside air into the cabin. This significantly increases the power consumption for heating and the driving range can be reduced to half of the normal range. This study introduces the Ceramic Humidity Regulator (CHR), a compact and energy-efficient device developed to address driving range improvement. The CHR uses a desiccant system to dehumidify the cabin, which can prevent window fogging without introducing cold outside air, thereby reducing heating power consumption. A desiccant system typically consists of two
Hamada, Takafumi, Shinoda, Narimasa, Konno, Yoshiki, Ihara, Yukio, Ito, Masaki
Technical Paper
Comparative Analysis of Mass Estimation Methods for Heavy-Duty Vehicles under Varying Payload Conditions2025-01-8209To be published on 04/01/2025
Accurate mass estimation is essential for commercial heavy-duty vehicles (HDVs), as fluctuating payloads significantly impact energy consumption. Precise vehicle mass estimates enhance the accuracy of energy consumption models, leading to more effective energy management systems and performance optimization strategies. For example, improved energy estimates can lead to more optimized routing and refueling schedules, improving operational efficiency and reducing costs. In the context of electrification, accurate mass estimates can inform battery sizing, range predictions, and charging requirements, enabling optimized charge scheduling and seamless integration of electric HDVs into existing operations. While direct mass measurements may be obtained through external weight-in-motion or specialized onboard weighing systems, this paper focuses on methods that use data from Controller Area Network (CAN) systems for alternative real-time predictions. The challenge lies in identifying a method
Jayaprakash, Bharat, Eagon, Matthew, Fakhimi, Setayesh, Kotz, Andrew, Northrop, William
Technical Paper
Smart Boosting: A Control Strategy for Optimized Energy Management with Boost Converter in Hybrid Electric Vehicles2025-01-8580To be published on 04/01/2025
In hybrid electric vehicles (HEVs), optimizing energy management and reducing system losses are critical for enhancing overall efficiency and performance. This paper presents a novel control strategy for the boost converter in hybrid electric vehicles (HEVs), aimed at minimizing energy losses and optimizing performance by modulating to a higher boost converter voltage only when necessary. Traditional approaches to boost converter control often lead to unnecessary energy consumption by maintaining higher voltage levels even when not required. In contrast, the proposed strategy dynamically adjusts the converter's operation based on real-time vehicle demands, such as driver input, Engine Start-Stop (ESS) events, Active Electric Motor Damping (AEMD), entry and exit transitions for Engine Fuel Cut-Off (DFCO), Noise-Vibration-Harshness (NVH) events like lash-zone crossing and other specific operational conditions. The control strategy leverages predictive algorithms and real-time monitoring
Basutkar, Ameya, Berger, Daniel, Huo, Shichao, Sullivan, Claire, Tischendorf, Christoph
Technical Paper
A Minimalist High-Power Boost Charging Solution Integrated Into Electric Drives2025-01-8560To be published on 04/01/2025
The drive power and charging performance of leading electric vehicles (EVs) continue to advance, with high-performance EVs elevating their high-voltage platform ranges from below 500V to 800V and even 900V. To be compatible with existing public charging stations of lower voltage, vehicles with high-voltage platforms often equip a boost charge device. However, this boost charge device incurs additional costs, weight, and space requirements. Most mature solutions employ an additional DC-DC boost converter, which, however, results in low charging power at a high cost. Some new approaches utilize the power switching devices and motor inductance of electric drives to form a boost converter circuit, using a three-phase current in-phase control strategy for charging. This method requires external inductors to reduce charging current ripples. Alternatively, to minimize current ripple without external inductors, a two-phase parallel and one-phase series topology is used, albeit at the expense
Yuan, Baocheng, Ma, Yong, Xie, Xi, Liu, Shaowei, Guan, Tianyu, Ge, Kai, Zheng, Lifu, Xu, Xu
Technical Paper
Easy Bike Solar PV System Charging Station Design and Simulation2025-01-8119To be published on 04/01/2025
Design and Simulation of an easy bike charging station in Lubbock, Texas is discussed in this paper. This study outlines the utilization of an easy bike charging station integrated with solar photovoltaic (PV) and battery energy storage systems (BESS) to improve grid stability by regulating voltage and frequency. The charging station is designed to have 24 DC fast charging ports and charge each easy bike simultaneously having the capacity to charge up to 100 easy bikes daily. The integration of the battery energy storage system is to ensure consistent power availability at all times, even during periods of low solar radiation. The paper shows the aspects of grid stability, which includes voltage and frequency regulation. System Advisor Model (SAM) was used in this study, and IEEE standard compliance was ensured in all calculations
SHODIMU, ADEDOLAPO LATIFAT
Technical Paper
Telematics-based Managed EV Charging: A pilot case study for utility bulk and distribution grid services2025-01-8122To be published on 04/01/2025
Growth in the EV market is resulting in an unprecedented increase of electrical load from EV charging at the household level. This has led to concern for electric utilities' ability to upgrade electrical distribution infrastructure at an affordable cost and sufficient speed that can keep up with EV sales. Adoption of EVs in the California market has outpaced the national average and offers early insight for other regions of the United States. The Sacramento Municipal Utility District (SMUD) partnered with two Distributed Energy Resource (DER) aggregators, the OVGIP (recently formed as ChargeScape) and Optiwatt, to deliver a vehicle telematics-based active managed charging pilot. This pilot was launched in Summer 2022, with approximately 1,200 EVs enrolled over two years including Tesla, Ford, BMW, and GM electric vehicles. The goal of this pilot was to evaluate the business case for mitigating EV grid impacts and delivering additional grid services providing both EV drivers and the
Liddell, Chelsea, Schaefer, Walter, Dreffs, Kora, Moul, Jacob, Kay, Carol, Aswani, Deepak
Technical Paper
Investigation of Impedance Evolution for Lithium Plating Detection During Multi-Stage Constant Current Fast Charging of Lithium-Ion Batteries2025-01-8124To be published on 04/01/2025
The lengthy charging times of lithium-ion batteries for electric vehicles (EVs) significantly affect their acceptance. Reducing charging time requires high-power fast charging. However, such fast charging can trigger various side reactions, leading to safety and durability issues. Among these, lithium plating is a major concern as it can reduce battery capacity and potentially cause internal short circuits or even thermal runaway. Currently, multi-stage constant current charging (MCCC) protocols are widely adopted. However, the difficulty in effectively detecting lithium plating during the MCCC process significantly limits the charging power. Therefore, it is urgent to explore a method to detect lithium plating during the MCCC process. In this study, the impedance evolution during the MCCC procedure was first investigated. Then a method based on the impedance variation patterns was proposed to detect lithium plating. Besides, the corresponding mechanism was further investigated
Shen, Yudong, Wang, Xueyuan, Wu, Hang, Wei, Xuezhe, Dai, Haifeng
Technical Paper
User Satisfaction Classification and Service Optimization of Electric Vehicle Charging Stations: An Empirical Study Based on Amap Data2025-01-8115To be published on 04/01/2025
With the rapid expansion of the electric vehicle (EV) market, enhancing charging infrastructure and service quality has become critical in shaping the overall user experience. User satisfaction with charging station services plays a crucial role in promoting the widespread adoption of electric vehicles. Ensuring that users have access to reliable, fast, and convenient charging services is essential for the growth and success of the EV market. This study focuses on the Guangzhou Panyu District, where user data on charging station experiences was collected from the Amap API platform. The data includes users' comments, satisfaction scores, and charging station locations, providing valuable insights into the experiences of EV users across various equipment suppliers. By leveraging user reviews and satisfaction ratings, we applied a combination of Significance Testing in Linear Regression and K-means Clustering Analysis to quantify and categorize user satisfaction with charging station
Guo, Haifeng, Ou, Shiqi(Shawn), Jing, Hao, Qi, Hao, Shi, Lanxin
Technical Paper
Optimal Energy Management of Parallel Electric-Hydraulic Hybrid Vehicles based on Dynamic Programming and Recurrent Neural Networks2025-01-8582To be published on 04/01/2025
This paper presents an approach for optimal energy management in parallel electric-hydraulic hybrid vehicles using recurrent neural networks trained through dynamic programming results. While electric vehicles are increasingly recognized for their sustainability and zero tailpipe emissions, their implementation faces critical challenges, especially in heavy-duty applications. The low power density of lithium-ion batteries limits their ability to effectively capture regenerative braking energy, particularly during short braking periods. In addition, high peak current loads due to heavy torque demands can accelerate battery aging. To address these challenges, a hybrid vehicle that combines electric and hydraulic systems has been proposed in the literature. This vehicle integrates a hydraulic pump/motor and a hydro-pneumatic accumulator with an electric powertrain, aiming to achieve both high power density and energy density while mitigating peak loads on the battery. Like other hybrid
Taaghi, Amirhossein, Yoon, Yongsoon
Technical Paper
Coupled Routing and Charge Schedule Optimization of Electrified Delivery Truck Fleets Feasibility Analyses2025-01-8602To be published on 04/01/2025
Electrifying truck fleets has the potential to improve energy efficiency and reduce carbon emissions from the freight transportation sector. However, the range limitations and substantial capital costs with current battery technologies imposes constraints that challenge the overall cost feasibility of electrifying fleets for logistics companies. In this paper, we investigate the feasibility via coupled routing and charge scheduling optimization of a delivery fleet serving a large urban area. To this end, we first build an improved energy consumption rate model for a Class 7-8 electric and diesel truck using a data-driven approach of generating energy consumption data from powertrain simulations on numerous drive cycles. We then conduct several analyses on the impact of battery size, cost, and electricity prices on the feasibility of fleet electrification at different penetration levels, considering availability of fast charging at the depot. Findings indicate that at typical energy
Wendimagegnehu, Yared Tadesse, Ayalew, Beshah, Ivanco, Andrej, Hailemichael, Habtamu
Technical Paper
Evaluation and Prevention of Brake Drum Freezing by Aerodynamic Measures2025-01-8775To be published on 04/01/2025
The use of drum brakes in Battery Electric Vehicles (BEVs) offers numerous benefits, including energy efficiency, reduced brake dust emissions, and reliable performance under challenging weather conditions. The capability of regenerative braking reduces the friction brake application frequency in BEVs and therefore the brakes can be prone to corrosion and performance degradation especially considering conventional disc brake systems. The closed design of a drum brake prevents corrosion of the friction-components by sealing out water, dirt or snow. A common sealing concept is performed with a labyrinth between the gap of the rotating drum and the axle mounted backplate. A hermetically isolation of water and snow ingress into the drum cannot be achieved with this concept, so additional aerodynamic measures are necessary to deflect the air/water path and protect the inner brake components. Additionally, interfaces like wheel cylinders, electric park brake parts, brake shoe pins, and axle
Hennicke, Tim, Kuthada, Timo, Bernhard, Adrian, Reichhart, Leander, Weber, Eugen, Moers, Michael, Rettig, Marc
Technical Paper
Study on Emergency Obstacle Avoidance Lateral Stability Control of Tractor Semitrailer Vehicles2025-01-8296To be published on 04/01/2025
As a crucial component of highway freight systems, tractor semitrailer vehicles play a key role in the transportation industry. However, their complex vehicle structure can lead to significant lateral instability during emergency obstacle avoidance, posing challenges to the vehicle's dynamic stability and safety. To enhance the emergency obstacle avoidance lateral stability of tractor semitrailer vehicles, a direct yaw moment lateral stability control strategy based on differential driving/braking is proposed. First, a 3-degree-of-freedom ideal linear dynamic model of the tractor semitrailer is established, and the accuracy of this model is validated. Subsequently, an emergency obstacle avoidance lateral stability control strategy for tractor semitrailer vehicles is proposed. The upper-level controller adopts a model-free adaptive control (MFAC) method to track the target yaw rate and vehicle sideslip angle, while the lower-level controller is designed to optimize tire load
Guo, Shaozhong, Dou, Jingyang
Technical Paper
Optimization of Electric Vehicle Battery Charging Strategy Based on Reinforcement Learning2025-01-8116To be published on 04/01/2025
The battery capacity of electric vehicles (EVs) is a critical factor influencing their overall performance. Selecting an appropriate charging strategy based on the EV driver’s travel behaviors can significantly mitigate battery capacity degradation and prolong its lifespan. This study integrated a physics-based battery degradation model with an EV powertrain system energy consumption model to enhance the prediction accuracy for the battery status under real-world driving conditions. In addition, it employed the Q-learning algorithm to provide suggestions on the driver’s charging behaviors, including charging start time, charging duration, and charger types. To create a reasonable reward function in the Q-learning algorithm, this study addressed the issue of car rental costs when the battery capacity is insufficient to support daily mileage. With the algorithm, this study modeled the 3-year use of an EV by an average driver sampled from the New England area in the U.S. The simulation
Wang, Jiayi, Jing, Hao, Ou, Shiqi(Shawn), Lin, Zhenhong
Technical Paper
Analysis of Geo-Location Data from Military Tactical Vehicles to Derive Wireless Recharging Requirements2025-01-8341To be published on 04/01/2025
As the military community considers the use of electrified tactical vehicles, wireless power transfer has emerged as a desirable method for recharging these vehicles. This technique enables multiple vehicles to recharge while in close proximity during motor pool or patrol base operations. A mobile wireless recharging platform could be deployed to these vehicle concentrations for recharging. This study evaluates the feasibility and requirements of such a system by examining the duration that vehicles remain close enough for effective power transfer. Vehicle geo-location data from the National Training Center for an infantry brigade combat team, encompassing over 400 tactical vehicles, is used to map vehicle movements. The study involves the extraction, cleaning, and analysis of this data to identify periods when vehicles are grouped closely enough to facilitate wireless recharging. The analysis quantifies the time vehicles spend in proximity and the average distance between them to
Mittal, Vikram, El Ouadi, Ameir
Technical Paper
A Multifunctional Integrated Three-Level Inverter for Electric Vehicle Application2025-01-8567To be published on 04/01/2025
This paper demonstrates a highly integrated 4-in-1 power electronics solution for 800V electric vehicle applications. combines the functionalities of on-board charging, DC boost charging, motor traction, and high-voltage/low-voltage power conversion, all within a single housing. A high level of integration is achieved by using motor windings for charging and a specially designed three-port transformer that magnetically couples high-voltage (HV) and low-voltage (LV) batteries while maintaining galvanic isolation. Additionally, the SuperBox system utilizes a three-phase open-ended-winding machine to facilitate both three-phase and single-phase AC charging. The dual-bank DC/DC architecture allows for the seamless integration of a redundant auxiliary power module, ensuring autonomous and functional safety. During AC charging mode, the T-type three-level (3L) inverter is repurposed as a Vienna three-phase Power Factor Correction (PFC) for three-phase on-board charging or as a totem-pole PFC
Wang, Yicheng, Taha, Wesam, Anand, Aniket
Technical Paper
DCFC EVSE Security2025-01-8118To be published on 04/01/2025
The rapid spread of electric vehicles (EVs) and EV charging stations requires an urgent focus on the security of the entire charging infrastructure. As EV charging stations are a major interface in the charging infrastructure, ensuring cybersecurity of the personal and private data transmitted to and from chargers is a key component to the overall security. To evaluate the security of a part of the EV charging ecosystem, researchers from Southwest Research Institute® (SwRI®) assessed the vulnerability of a DC Fast Charging (DCFC) EV Supply Equipment (EVSE)’s communication protocol and system. The researchers established an undetected Adversary in the Middle (AitM) between the EV and EVSE to examine the communication used between the two. They identified vulnerabilities that exposed critical data—such as the MAC address of both the EV and EVSE—either sent in plaintext or encrypted with a known algorithm. These values allowed for reprogramming of the non-volatile memory of Power-Line
Kozan, Katherine
Technical Paper
Driver-Centric Direct Current Fast Charging of Electric Vehicles via Energy Optimal Thermal Management2025-01-8374To be published on 04/01/2025
Charging a battery electric vehicle at extreme temperatures can lead to battery deterioration without proper thermal management. To avoid battery degradation, charging current is generally limited at extreme hot and cold battery temperatures. Splitting the wall power between charging and the thermal management system with the aim of minimizing charging time is a challenging problem especially with the strong thermal coupling with the charging current. Existing research focus on formulating the battery thermal management control problem as a minimum charging time optimal control problem. The current control strategy forces the driver to charge with minimum time and higher charging cost irrespective of their driving schedule. This paper presents a driver-centric DCFC control framework by formulating the power split between thermal management and charging as an optimal control problem with the goal of improving the wall-to-vehicle energy efficiency. Proposed energy-efficient charging
Gupta, Shobhit, Kang, Jun-Mo, Zhu, Yongjie, Lee, Chunhao, Zanardelli, Wesley
Technical Paper
SAE TOMORROW TODAY BRIEFS - Top EV Trends to Watch in 20251349601/16/2025
2024 saw several advancements in EV technology and charging capabilities including the rollout of the National Electric Vehicle Infrastructure (NEVI) program and the growing adoption of the J3400 charging standard. Looking ahead to 2025, new EV models and more affordable options are poised to make an impact, capturing public interest and continuing to drive adoption, even amidst current EV infrastructure challenges and the potential rollback of EV tax credits. To break down the key EV headlines of 2024 and what to expect in the year ahead, Roberto Baldwin, Sustainability Editor, SAE Sustainable Mobility Solutions, sat down with Patrick George, Editor-in-Chief of InsideEVs, the go-to online publications for all things electrification. For more information on the evolution of sustainability, head on over to sustainablecareers.sae.org. There, you can learn about the announcement of the universal plug and charge platform. We'd love to hear from you. Share your comments, questions and ideas
Hineman, Marcie
Podcast
SAE TOMORROW TODAY BRIEFS - How to Scale EV Charging at Gas Stations1349312/30/2024
As EV charging infrastructure grows and evolves, so too does the role of gas stations, convenience stores, and auto repair shops -- all of which are key players in a thriving mobility ecosystem. Enter Vontier, a global industrial technology company transforming fueling and charging infrastructure, convenience store technology and fleet management. By helping service station owners become "charge point operators," Vontier is a enabling a shift to better support consumers? needs and increase profitability in an evolving market. To learn more, Roberto Baldwin, Sustainability Editor, SAE Sustainable Mobility Solutions, sat down with Mark Morelli, CEO, Vontier, to discuss how his company is harnessing its market-leading expertise in mobility technologies to usher in a new era of convenience. For more information on the evolution of sustainability, head on over to sustainablecareers.sae.org. There, you can learn about the latest EV announcements from the LA Auto Show including the Hyundai
Hineman, Marcie
Podcast
Evaluation of Fast Charging Efficiency under Extreme Environmental Conditions in Brazil2024-36-008712/20/2024
Fast chargers are necessary for the success of vehicle electrification. These devices can achieve a battery charge rate greater than 4C, significantly increasing the amount of heat generated by the battery. Additionally, the operating temperature of the storage device directly influences the device’s efficiency and lifespan. Given the importance of operation temperature, the Battery Management System (BMS) plays a key role in mitigating heat generation and degradation effects. Despite BMS optimizing battery operation under all possible conditions, the use of fast chargers in extremely hot and cold environments still lowers overall efficiency. In these two worst-case scenarios, the thermal system must manage the ideal charging temperature by consuming part of the energy supplied by the charger. The present work aims to evaluate the charging energy efficiency and time with fast charger utilization, considering the Brazil’s minimum and maximum temperatures registered in 2020. In order to
Pires, Rodrigo Alonso, Pontes, Diego Augusto, Souza, Rafael Barbosa, Oliveira, Matheus Leonardo Araújo, Rodrigues, Luiz Fernando Alves, Fernandes, Heder, Maia, Thales Alexandre Carvalho
Technical Paper
A Method for HPR Critical Routes Identification and Evaluation2024-28-015012/05/2024
Heavy-duty vehicles, particularly those towing higher weights, require a continuous/secondary braking system. While conventional vehicles employ Retarder or Engine brake systems, electric vehicles utilize recuperation for continuous braking. In a state where HV Battery is at 100% of SOC, recuperated energy from vehicle operation is passed on to HPR and it converts electrical energy into waste heat energy. This study focuses on identification of routes which are critical for High Power Brake Resistors (HPRs), by analyzing the elevation data of existing charging stations, the route’s slope distribution, and the vehicle’s battery SOC. This research ultimately suggests a method to identify HPR critical vehicle operational routes which can be useful for energy efficient route planning algorithms, leading to significant cost savings for customers and contributing to environmental sustainability
Thakur, Shivam, Salunke, Omkar, Ambuskar, Mandar, Pandey, Lokesh
Technical Paper
Cost Optimization Techniques for EV Charging Stations Based on Renewable Energy Sources and Grid Power2024-28-014612/05/2024
Adoption of Electric Vehicles (EVs) reduces air pollution by reducing harmful gas emissions. Such adoption, however, needs a reliable and convenient charging infrastructure, including smart EV charging. Renewable energy sources such as solar photovoltaic cells, battery and wind energy systems can address these infrastructural gaps which work in conjunction with main grid power supply thereby providing low-cost electricity. This paper introduces an energy management algorithm for integrated renewable and grid power sources available at charging stations across India that considers techno-economic and environmental factors. The current work proposes a supervisory controller model that manages the load power demand of the charging station. The controller effectively deploys low cost energy sources based on the status of all available power supplies and reduces the overall charging costs in real time. The energy management algorithm ensures adequate stand-alone energy generation and
Shukla, Ankit, Kushwah, Yogendra Singh, Suman, Saurabh
Technical Paper
A Comprehensive Review of Advancement in Anode Material with Modified Architecture for Lithium-Ion Batteries2024-28-014212/05/2024
Anode material, responsible for the critical storage and release of lithium ions during charge and discharge cycles, holds paramount importance. By strategically altering the material design and composition of the current graphite, researchers aim to significantly improve fast charging capabilities, energy density, cycling stability and overall electrochemical kinetics within Lithium ion battery. Anode materials operate through three primary mechanisms: insertion/de-insertion that is allowing for reversible lithium ion accommodation within the host structure; alloying, where lithium ions form chemical bonds with the anode material; and conversion reactions, involving the creation of new phases during charge/discharge cycles. This review delves into a captivating array of advanced anode materials with the potential to surpass the limitations of traditional graphite. Carbon-based nanomaterials like graphene and its derivative, reduced graphene oxide, offer exceptional conductivity and
Borkar, Shweta, Nahalde, Sujay, Ruban J S, Alwin, More, Hemant
Technical Paper
Battery Digital Twin with Edge Deployment2024-28-012012/05/2024
Today's battery management systems include cloud-based predictive analytics technologies. When the first data is sent to the cloud, battery digital twin models begin to run. This allows for the prediction of critical parameters such as state of charge (SOC), state of health (SOH), remaining useful life (RUL), and the possibility of thermal runaway events. The battery and the automobile are dynamic systems that must be monitored in real time. However, relying only on cloud-based computations adds significant latency to time-sensitive procedures such as thermal runaway monitoring. Because automobiles operate in various areas throughout the intended path of travel, internet connectivity varies, resulting in a delay in data delivery to the cloud. As a result, the inherent lag in data transfer between the cloud and cars challenges the present deployment of cloud-based real-time monitoring solutions. This study proposes applying a thermal runaway model on edge devices as a strategy to reduce
Sarkar, Prasanta, Pardeshi, Rutuja, Kharwandikar, Anand, Kondhare, Manish
Technical Paper
Automotive Engineering: December 202424AUTP1212/05/2024
Integrating sensor data: Selecting an ADAS decision-making process Exactly when sensor fusion occurs in ADAS operations, late or early, impacts the entire system. New fluids coming for EV thermal management Balancing low conductivity, corrosion resistance and optimum heat transfer in next-generation EV coolants while meeting new EV safety regulations. Inside the quiet, looming battle over automotive refrigerants R-1234yf is used in almost every new car sold in the U.S., but the EU is discussing a ban and the industry is investigating alternatives like CO2 and propane. Editorial China's warning signs Supplier Eye Ode to 2024: A critical year for the auto industry Battery analysis pioneer: North America has five years to catch China Lowering carbon emissions? What's being done for internal combustion engines What it takes to make tire data useful to non-engineers Experts: J3400 isn't just a plug, but a complete system Ford Engineering Lab turns 100, hosts new team Pure Lithium bets on
Magazine Issue
SoC Estimation for LFP Battery Using Extended Kalman Filter and Particle Filter with Adaptive Battery Parameters2024-28-022312/05/2024
In recent years, Lithium Iron Phosphate (LFP) has become a popular choice for Li-ion battery (LIB) chemistry in Electric Vehicles (EVs) and energy storage systems (ESS) due to its safety, long lifecycle, absence of cobalt and nickel, and reliance on common raw materials, which mitigates supply chain challenges. State-of-charge (SoC) is a crucial parameter for optimal and safe battery operation. With advancements in battery technology, there is an increasing need to develop and refine existing estimation techniques for accurately determining critical battery parameters like SoC. LFP batteries' flat voltage characteristics over a wide SoC range challenge traditional SoC estimation algorithms, leading to less accurate estimations. To address these challenges, this study proposes EKF and PF-based SoC estimation algorithms for LFP batteries. A second-order RC Equivalent Circuit Model (ECM) was used as the dynamic battery model, with model parameters varying as a function of SoC and
Ns, Farhan Ahamed Hameed, Jha, Kaushal, Shankar Ram, C S
Technical Paper
New fluids coming for EV thermal management24AUTP12_0212/01/2024
Balancing low conductivity, corrosion resistance and optimum heat transfer in next-generation EV coolants while meeting new EV safety regulations. Managing the heating and cooling of electric vehicle propulsion systems may seem to be an easy task compared with combustion engines. After all, ICEs run much hotter-the thermal optimum for a gasoline engine is around 212 F (100 C). By comparison, EV batteries normally generate (as a function of current during charge/discharge cycles) a relatively cool 59-86 F (15-30 C). And while motors and power electronics operate hotter, typically 140-176 F (60-80 C), they still run cooler than ICEs. But among the myriad complexities of EV thermal management are batteries' dislike for temperature extremes, new cell chemistries, heat-generating high-voltage electrical architectures and 800V fast charging. All are putting greater focus on maintaining stable EV battery thermal performance and safety. Experts note that compatibility among the cell chemistry
Brooke, Lindsay
Magazine Article
Komatsu employs ‘slick’ battery swapping for underground LHD machine24TOFHP12_1012/01/2024
Komatsu introduced its first battery-electric load-haul-dump (LHD) machine, the WX04B, at the MINExpo tradeshow in September. The WX04B is designed specifically for narrow vein mines in underground hard rock mining operations. Komatsu is pairing the electric LHD with its new OEM-agnostic 150-kW battery charger that was also revealed in Las Vegas. The 4-tonne WX04B LHD features what Komatsu claims is best-in-class energy density, offering up to four hours of runtime on a single charge. The Li-ion NMC (nickel-manganese-cobalt) battery from Proterra has a capacity of 165 kWh and nominal voltage of 660 V. Fewer charge cycles are needed compared to competitors, the company claims, which helps to maximize operational efficiency and minimize downtime. Proterra and Komatsu began their collaboration on the LHD's H Series battery system in 2021, long before Komatsu's acquisition of American Battery Solutions (ABS) in December 2023
Gehm, Ryan
Magazine Article
Liebherr, Fortescue reveal towering battery-electric T 264 haul truck24TOFHP12_1112/01/2024
Liebherr and Fortescue unveiled their first autonomous battery-electric T 264 haul truck at MINExpo 2024, garnering a steady stream of attendees eyeing and climbing on the giant machine. The truck is the culmination of nearly three years of development work and collaboration among the autonomy and zero-emission units of Liebherr and Fortescue. The T 264 electric hauler features a 3.2-MWh battery system, comprising eight sub-packs, developed by Fortescue Zero. Fortescue also developed a stationary fast-charging solution to support the new T 264. The charger will be available in both manual and robotic versions. An automated quick charger of up to 6 MW with two megawatt charging system (MCS) plugs can reportedly charge the current battery-electric T 264 in 30 minutes
Gehm, Ryan
Magazine Article
CATL expands battery range for heavy-duty trucks and buses24TOFHP12_0512/01/2024
Chinese battery manufacturer CATL (Contemporary Amperex Technology Co. Ltd.) completed the launch of its TECTRANS battery system for the commercial transport sector at IAA Transportation, which took place in September in Hanover, Germany. CATL added its heavy-duty truck and bus/coach battery ranges to the light-truck range that the company launched in China in July 2024. For heavy-duty trucks, CATL offers two alternatives: the TECTRANS - T Superfast Charging Edition and the TECTRANS - T Long Life Edition. As the name suggests, the Superfast Charging Edition is designed to offer rapid charging capability for operators needing to recharge during a duty cycle. CATL quotes a 4C peak charging rate, which would permit a charge to 70% in 15 minutes
Kendall, John, Gehm, Ryan
Magazine Article
Experts: J3400 isn't just a plug, but a complete system24AUTP12_0912/01/2024
The auto industry took the next step in the evolution of North American electric vehicle charging solutions today at The Battery Show in Detroit. That's where SAE International released its NACS J3400 Recommended Practice document. Technically called the “SAE J3400TM: NACS Electric Vehicle Coupler Technical Recommended Practice,” the RP can be considered a “blueprint to build” and should set off a stream of new products from suppliers that OEMs and third-party groups like UL will soon test, said Rodney McGee, chairman of the SAE J3400 NACS Task Force and a research engineer at the Transportation Electrification Center at the University of Delaware
Blanco, Sebastian
Magazine Article
Robust, Versatile and Safe Lithium-Ion Batteries for Military Vehicle Applications2024-01-401411/15/2024
ABSTRACT Rechargeable batteries needed for military applications face critical challenges including performance at extreme temperatures, compatibility with military logistical processes, phasing out of legacy battery technologies, and poor compatibility of COTS lithium-ion batteries with specialized military operational requirements and legacy platforms. To meet these challenges, CAMX Power has developed and is commercializing a lithium-ion battery technology, trademarked CELX-RC®, with high power and rapid charging capability, long life, exceptional performance and charge acceptance capability at extreme low temperatures (e.g., -60 ºC), excellent safety, capability for discharge and storage at 0V, and ability to be implemented in batteries without management systems. This paper describes CELX-RC technology and its implementation in prototype batteries. Citation: D. Ofer, J. Bernier, E. Siegal, M. Rutberg, S. Dalton-Castor, “Robust, Versatile and Safe Lithium-Ion Batteries for Military
Ofer, David, Bernier, Joe, Siegal, Edward, Rutberg, Michael, Dalton-Castor, Sharon
Technical Paper
FIRE PROPAGATION IN CYLINDRICAL LI-ION BATTERIES UNDER ULTRA-HIGH STRAIN-RATE DEFORMATION2024-01-396011/15/2024
ABSTRACT Abuse response of lithium-ion batteries has been extensively studied over several decades. Most studies on the onset and propagation of battery fires following mechanical deformation are focused on understanding the onset of thermal events following quasi-static loading. Using an array of cylindrical lithium-ion cells as example, we report results from ultra-high strain-rate deformation mechanical events (> 100 /s) that result in electrochemical short-circuits followed by thermal events. We present a methodology that takes stock of gas compositions as a function of state of charge and compute flammability limits. Finally, we discuss implications for flame lengths and propensity for propagation of thermal events. Citation: J. Kim, A. Mallarapu, S. Santhanagopalan, Y. Ding, “Propagation of Fire in Li-Ion Batteries under Ultra-High Strain-Rate Deformation” In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA, Novi, MI, Aug. 16-18, 2022
Kim, Jinyong, Mallarapu, Anudeep, Santhanagopalan, Shriram, Ding, Yi
Technical Paper
NMP–free Lithium Ion for Sustainable Manufacturing in Silent-Watch Applications2024-01-394611/15/2024
ABSTRACT PPG formulates N-methyl pyrrolidone free (NMP−free) cathodes for Li−ion batteries capable of delivering sufficient power for automotive starting, lighting and ignition (SLI) as well as adequate charge capacity for powering auxiliary electronics. In this paper, NMP−free energy cathodes and power cathodes were formulated using developmental binders, and refinement of carbon/binder ratio and slurry mix procedure. Learnings from the energy and power cathode development were conceptually combined in the formulation of capacity enhanced power cathodes. These cathodes were evaluated electrochemically via power capability and rate capability testing in battery coin cells, as well as in 0.5 Ah multilayer pouch cells. Carbon content was found to be a critical factor in attaining high cold crank performance. This work represents significant steps toward potential commercialization of NMP−free cathode coated foil for Li−ion batteries. Citation: S. Esarey, A. Kizzie, C. Woodley, I. Matts
Esarey, Samuel L., Kizzie, Austin, Woodley, Christopher, Matts, Ian, Hellring, Stuart, Zhou, Zhilian, Terrago, Gina
Technical Paper
Study on the Electrohydrodynamic Performance of a Multiple Wire-Cylinder Ionic Wind Generation System2024-01-701011/15/2024
Electrohydrodynamic (EHD) technology, noted for its absence of moving mechanical parts and silent operation, has attracted significant interest in plane propulsion. However, its low thrust and efficiency remain key challenges hindering broader adoption. This study investigates methods to enhance the propulsion and efficiency of EHD systems, by examining the electrohydrodynamic flow within a wire-cylinder corona structure through both experimental and numerical approaches. A multi-wire-cylinder positive corona discharge experimental platform was established using 3D printing technology, and measurements of flow velocity, voltage, and current at the cathode outlet were conducted. A two-dimensional simulation model for multi-wire-cylinder positive corona discharge was developed using Navier-Stokes equations and FLUENT user-defined functions (UDF), with the simulation results validated against experimental data. The analysis focused on the effects of varying anode diameters and the
Huang, Guozhao, Dong, Guangyu, Zhou, Yanxiong
Technical Paper
CAM-7/LTO LITHIUM-ION CELLS FOR BATTERIES WITH HIGH CHARGE/DISCHARGE PERFORMANCE AT EXTREME LOW TEMPERATURE2024-01-336411/15/2024
ABSTRACT TIAX is developing laminated prismatic lithium-ion (Li-ion) cell technology capable of rapid charging at low temperature (to -50 °C) to replace current lead-acid vehicle batteries. The novel cells are based on TIAX’s high energy, high power CAM-7 cathode material, high rate capability lithium titanate (LTO) anode material, and novel electrolyte formulation, and target cell-level energy content greater than 90 Wh/kg and 250 Wh/l. CAM-7 cathode material promises significant boost in power and run time of Li-Ion batteries for a wide range of DoD applications, and is now being commercialized by a separate company, CAMX Power, which is scaling up production in a 50 metric ton per year plant installed in Massachusetts
Ofer, David, Dalton-Castor, Sharon, Nation, Leah, Pullen, Adrian, Rempel, Jane, Barnett, Brian, Sriramulu, Suresh
Technical Paper
Simulation of Microgrid and Mobile Power Transfer System interaction using Distributed Multiobjective Evolutionary Algorithms2024-01-347911/15/2024
Abstract Optimization of a microgrid interacting with mobile power transfer systems is a multiobjective problem that grows to be computationally expensive as components and fidelity are added to the simulation. In previous work [17] we proposed an optimization strategy relying on evolutionary computing. With an evolutionary computing approach, seeking a well-distributed set of solutions on the entire optimal frontier necessitates a large population and frequent evaluation of the aforementioned simulation. With these challenges, and inspiration from Roy et al. [14] distributed pool architecture, we propose an architecture for distributed pool evolutionary computing that differs from the Roy et al. design. We use this strategy with a microgrid and mobile power transfer system simulation to optimize for cost and relaibility. We find that the distributed approach achieves increased performance in raw system execution time, and in some cases converges faster than a non distributed version
Dunn, Andrew G., Mange, Jeremy B., Skowronska, Annette G., Gorsich, David J., Pandey, Vijitashwa, Mourelatos, Zissimos P.
Technical Paper
CAM-7®/LTO Lithium-Ion Cells for Logistically Robust 6T Vehicle Batteries2024-01-362911/15/2024
ABSTRACT CAMX Power is developing Li-ion pouch cells and batteries based on its proprietary CAM-7® cathode material and commercially available lithium titanate (LTO) anode material to provide high power, high charging rate capability, long life, safety and configurational flexibility in military vehicle batteries. The CAM-7®/LTO technology can be discharged to 0 V with no loss in performance, has excellent tolerance for cell voltage reversal and cell overcharge as well as having excellent elevated-temperature storage stability, making it ideally suited for batteries that can be logistically managed with little or no maintenance or environmental controls. These same properties make CAM-7®/LTO technology well-suited for implementing in damage-tolerant, minimally managed, batteries that are structurally distributed and integrated in military vehicles
Ofer, David, Kaplan, Daniel, Menard, Mark, Yang, Celine, Dalton-Castor, Sharon, McCoy, Chris, Barnett, Brian, Sriramulu, Suresh
Technical Paper
A FAST AND SAFE QUASI-OPTIMAL CHARGING STRATEGY FOR LI-ION BATTERIES2024-01-379311/15/2024
ABSTRACT This paper presents a fast and safe quasi-optimal multistage constant current (MCC) charge pattern optimization strategy for Li-ion batteries. It is based on an integrated electro-thermal model that combines an electrical equivalent circuit (EEC) battery model with a thermal battery model. The EEC model is used to predict the battery’s terminal voltage continuously as charging progresses, while its temperature rise is also estimated continuously by employing the thermal model. This integrated electro-thermal battery model is utilized to search for an optimal MCC charge pattern that charges the battery in minimum time, while simultaneously limiting its temperature rise to a user-specified level. The search for the optimal charge pattern is carried out on a stage-by-stage basis by using a single-variable optimal search strategy that can be easily implemented on a battery management system. The paper also includes some simulation results obtained from an integrated electro
Das, Manohar, Jarid, Saad, Xu, Meng, Wang, Xia
Technical Paper
Wireless Charging for Autonomous Electric Vehicles2024-01-388211/15/2024
ABSTRACT Charging an autonomous electric vehicle can be a challenge using the traditional cable and connector approach. This paper explores various methods for the charging of batteries used in autonomous electric vehicles. One such method, an alternative to the traditional “contact” approach, utilizes a non-contacting power transfer technology that is based on magnetic induction and resonance principles. The paper examines various methods for the application of battery energy replenishment. A proposed charging station with design objectives is discussed, along with how well each of the battery energy replenishment methods would meet the proposed autonomous electric vehicle charging station requirements. Citation: Oly Jeon-Chapman, Ron Fiorello and Ronnie L. Wright, Ph.D., “Wireless Charging for Autonomous Electric Vehicles”, In Proceedings of the Ground Vehicle Systems Engineering and Technology Symposium (GVSETS), NDIA, Novi, MI, Aug. 13-15, 2021
Jeon-Chapman, Oly, Fiorello, Ron, Wright, Ronnie L.
Technical Paper
ELECTRIC VEHICLE CHARGING CYBERSECURITY2024-01-397911/15/2024
ABSTRACT Electric vehicles (EVs) are growing in popularity in both the defense and commercial sectors, with mandates and directives helping to inspire greater adoption. This increased popularity requires testing of an EV’s connected systems to ensure security against cyberattacks. The research efforts presented in this paper show that the EV battery management system (BMS) and SAE J1772 charging standard are susceptible to cyberattacks. Spoofing attacks on the vehicle’s J1772 charging interface can be used to limit or prevent charging of an EV’s battery. Penetration testing of an EV’s BMS shows how vulnerabilities can be exploited to successfully attack an EV through the Controller Area Network (CAN) bus on the vehicle. This paper also discusses the implications of these attacks from a defense standpoint with high-level protections also discussed
Dodson, Austin, Saenz, Patrick
Technical Paper
TACTICAL VEHICLE TO GRID AND VEHICLE TO VEHICLE DEMONSTRATION2024-01-359111/15/2024
ABSTRACT The roll-up roll-away Tactical Vehicle-to-Grid / Vehicle-to-Vehicle (V2G/V2V) system provides a plug-and-play, very fast forming, smart, aggregated, and efficient power solution for an emerging (including austere) contingency base that is ready to generate up to 240kW of 208 VAC 3-phase power in less than 20 minutes. The system is designed to provide grid services (peak shaving, Volt/VAR control, power regulation, and current source mode) beneficial to emerging and mature grids (CONUS or OCONUS). The system uses vehicle Transmission-Integrated Generators (TIGs) to produce 600VDC power for use by vehicle hotel-loads (electrification) and off-board loads (tents/shelters, communications centers, or other electrical loads). Each vehicle is equipped with a Vehicle Communication Module (VCM), which provided the communication capability prior to initiation of transfer of up to 100kW of power via the J1772 SAE Combo Connector between vehicles (V2V) and/or for export power off-vehicle
Hancock, Janie, Kolhoff, Steven W., McGrew, Dean Z., Masrur, M. Abul, Skowronska, Annette G., Vandiver, James, Gatherer, Jim, Palmer, Jason, Wood, Robert, Curtiss, Peter, Dorflinger, Max
Technical Paper
GLOBAL STRATEGIES FOR OPTIMIZING THE RELIABILITY AND PERFORMANCE OF U.S. ARMY MOBILE POWER TRANSFER SYSTEMS2024-01-341311/15/2024
ABSTRACT As the U.S. Army develops its 30-year science and technology strategy for ground systems, these systems are seen more as mobile power generation systems than just semi-autonomous mobile protection systems. As ground systems continue to have greater levels of electrification, they are perceived as key to providing power not only to the propulsion and mobility systems, but to protection systems, communications, information systems and a complex, ever-increasing suite of auxiliary power systems which are not limited to the vehicle platform itself, but to external systems and platforms. All power systems can be connected wirelessly, or through a microgrid. Therefore, optimizing the overall ground system along with an external suite of loads and sources through a power grid, as a system of systems, becomes crucial in vehicle design. This optimization problem for performance and reliability is complex when considering the outside grid and a mix of other sources and loads with
Skowronska, Annette G., Gorsich, David, Mange, Jeremy, Dunn, Andrew, Pandey, Vijitashwa, Mourelatos, Zissimos P.
Technical Paper
A MODEL PREDICTIVE CONTROL-BASED OPERATION OF VEHICLE-BORNE MICROGRID CONSIDERING BATTERY DEGRADATION2024-01-401611/15/2024
ABSTRACT Microgrids have garnered attention as they facilitate the integration of distributed renewable and non-renewable energy resources and allow flexibility to connect to the grid whenever required. When power is required for temporary missions or an emergency search and rescue mission, a vehicle-borne microgrid can supply critical power needs. In this paper, a vehicle-borne mobile microgrid consisting of a diesel generator, a battery storage system and solar panels mounted on the vehicle exterior is considered, and an operational control that minimizes the total fuel consumption and the battery degradation is formulated based on model predictive control. A simulation study is carried out considering a forward operating base mission scenario where the microgrid supplies the charging power to unmanned ground and aerial vehicles deployed in the mission. The result shows that the proposed approach is robust against uncertainties associated with renewable generation and the charging
Paudel, Saroj, Zhang, Jiangfeng, Ayalew, Beshah, Castanier, Matthew, Skowronska, Annette
Technical Paper
SOME INSIGHTS IN FAST CHARGE METHODS FOR NCA CELLS2024-01-401311/15/2024
ABSTRACT Low charge times are very desirable for battery electric vehicles. Lithium Nickel Cobalt Aluminum (NCA) chemistry is used in vehicles like the Tesla Model S for their energy density and also used in several consumer applications. Investigators used state of art NCA cells to conduct research into the tradeoffs between charge time, life and safety. Eight different charge profiles were compared. These included the standard CC-CV strategy and the state of the art Tesla Model S profile. Impact of temperature is also embedded in the selection of charge profiles. A non-dimensional charge metric is proposed as a composite of the impacts of charge time, effective charge stored, aging, overcharge sensitivity and lithium plating sensitivity. This metric is computed for all tested charge profiles and the best candidates are identified. Citation: Bapiraju Surampudi PhD, Ian Smith, Terry Alger PhD, “Some Insights in Fast Charge Methods for NCA Cells,” In Proceedings of the Ground Vehicle
Surampudi, Bapiraju, Smith, Ian, Alger, Terry
Technical Paper
THE ‘GUILLOTINE’ AN ADAPTIVE, ROBOTIC, ANTI-TANK PRECISION ATTACK SYSTEM2024-01-399311/15/2024
ABSTRACT Main Battle Tanks (MBTs) remain a key component of most modern militaries. While the best way to ‘kill a tank’ is via the employment of another tank, matching enemy armor formations one-for one is not always possible. Light infantry lack organic armor and their shoulder launched anti-tank capabilities do not defeat the latest generation of MBTs. To compensate for this capability gap, the U.S. Army has employed precision guided anti-tank munitions, such as the “Javelin.” However, these are expensive to produce in quantity and require risking the forward presence of dismounted Soldiers to employ. Mine fields offer another option but are immobile once employed. The ‘Guillotine’ Attack System proposes to change the equation by pairing an AI enabled, adaptive unmanned delivery system with a shaped charge payload. Guillotine can loiter for hours, reposition itself to hunt for targets, and- when ready- deliver a precision shaped charge strike from the air. Citation: “The ‘Guillotine
Dooley, Matthew, Lacaze, Alberto
Technical Paper
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