Criteria

Text:
Display:

Results

Viewing 1 to 30 of 188
2017-03-28
Technical Paper
2017-01-0157
Forrest Jehlik, Simeon Iliev, Eric Wood, Jeff Gonder
It is widely understood that cold ambient temperatures negatively impact vehicle system efficiency. This is due to increased friction (engine oil, transmission, and driveline viscous effects), cold start enrichment, heat transfer, and air density variations. Although the science of quantifying steady-state vehicle component efficiency is mature, transient component efficiency over dynamic ambient real-world conditions is less understood and quantified. This work characterizes transmission efficiency utilizing transmission heating technologies over various drive cycles and ambient conditions. Dynamometer testing over hot and cold ambient temperatures was conducted for two vehicles utilizing transmission warming technologies, and one vehicle using pads to pre-heat the transmission. For the vehicles with transmission heating technologies, tests were conducted with the systems both on and off to compare gains in efficiency.
2017-03-28
Technical Paper
2017-01-1210
R. Dyche Anderson, Regan Zane, Gregory Plett, Dragan Maksimovic, Kandler Smith, M. Scott Trimboli
A novel method of battery management was developed for large battery packs such as those used in Plug In Hybrid and Battery Electric Vehicles where the existing battery management system and DC/DC converter are replaced by an integrated, modular battery management-DC/DC converter system. The system contains of a number of small DC-DC converters in parallel with one or more cells. Differing loads through the DC-DC converters are used to differentially balance the various cells. This method has the increases battery life by reducing stress on the weaker cells in the battery. Simulations show life extensions of 30-50%, depending on the type of vehicle and the location. Different balancing strategies may be employed depending on the needs of the battery and vehicle. This method allows more range in older vehicles, as the range is no longer limited by the capacity of the weakest cell. The proposed system will not only allow a longer battery life, but the total system cost may be reduced.
2017-03-28
Technical Paper
2017-01-0186
Cory J. Kreutzer, John Rugh, Jeff Tomerlin
Increased market penetration of electric drive vehicles (EDVs) requires overcoming a number of hurdles including limited vehicle range and the elevated cost of EDVs in comparison to conventional vehicles. Climate control loads have a significant impact on range, cutting it by over 50% in both cooling and heating conditions. In order to minimize the impact of climate control on EDV range, the National Renewable Energy Laboratory has partnered with Hyundai America and key industry partners to quantify the performance of thermal load reduction technologies on a Hyundai Sonata PHEV. Technologies that impact vehicle cabin heating in cold weather conditions and cabin cooling in warm weather conditions were evaluated. Tests included thermal transient and steady-state periods for all technologies, including the development of a new test methodology to evaluate the performance of occupant thermal conditioning.
2017-03-28
Journal Article
2017-01-0868
Robert L. McCormick, Gina Fioroni, Lisa Fouts, Earl Christensen, Janet Yanowitz, Evgueni Polikarpov, Karl Albrecht, Daniel J. Gaspar, John Gladden, Anthe George
Reducing greenhouse gas emissions from the light-duty transportation sector will require both low-net-carbon fuels and significant improvements in vehicle and engine efficiency. More highly efficient engines will employ higher compression ratio, and higher power density turbocharged engines that enable smaller swept displacement volume (downsizing) and operation at lower engine speeds (downspeeding). These technologies can be pursued more aggressively with fuels that have greater knock resistance than fuels on the market today. We describe a study to identify potential biofuels that enable these spark ignition (SI) engine efficiency strategies. A list of potential biomass-derived blendstocks (both single components and mixtures) that can be produced thermochemically, biochemically, or by hybrid processes was developed. An online database of properties and characteristics of these bioblendstocks was created and populated.
2017-03-28
Journal Article
2017-01-0892
Eric Wood, Jeffrey Gonder, Forrest Jehlik
Increased access to large datasets of real-world drive cycles is driving demand for vehicle powertrain models capable of rapidly estimating real-world fuel economy. Whether for component design tradeoff studies or regulatory analysis, the need for powertrain models to achieve high levels of accuracy with low runtimes is critical. One approach is to develop simplified models that can be calibrated to controlled laboratory testing. However, many of the factors impacting real-world fuel economy are often left unexplored in the controlled laboratory setting. This paper seeks to quantify the ability of a simplified vehicle model, calibrated to laboratory test data, to accurately estimate real-world fuel economy in an uncontrolled, on-road environment. Model validation results from over 2,500 miles of on-road testing are presented for a representative, conventional gasoline, mid-size sedan equipped with laboratory-grade instrumentation.
2017-03-28
Journal Article
2017-01-0901
Alex Pink, Adam Ragatz, Lijuan Wang, Eric Wood, Jeffrey Gonder
Vehicles continuously report real-time fuel consumption estimates over their data bus, known as the controller area network (CAN). However, the accuracy of these fueling estimates is uncertain to researchers who collect these data from any given vehicle. To assess the accuracy of these estimates, CAN ­reported fuel consumption data are compared against fuel measurements from precise instrumentation. The data analyzed consisted of eight medium/heavy-­duty vehicles and two medium-­duty engines. Varying discrepancies between CAN fueling rates and the more accurate measurements emerged but without a vehicular trend—for some vehicles the CAN under-­reported fuel consumption and for others the CAN over­-reported fuel consumption. Furthermore, a qualitative real-time analysis revealed that the operating conditions under which these fueling discrepancies arose varied among vehicles.
2017-03-28
Technical Paper
2017-01-0191
Gene Titov, Jason Aaron Lustbader
Passenger comfort and vehicle component thermal management systems of advanced electric vehicles (EVs) can be highly integrated designs. While capable of substantially increasing the range, these systems are complex with a large number of possible modes of operation. Effective control strategies become a key in successful application of such systems while simulations in place of extensive testing may substantially reduce the cost of their development. The National Renewable Energy Laboratory previously developed a combined thermal management system simulation model in MATLAB/Simulink that included refrigerant and coolant loops, and validated its performance against bench test data. This paper provides details of control strategies developed for NREL’s combined coolant loop system concept. Simulation results over drive cycles demonstrate dynamic mode switching within the modeling framework. Results show the potential for significant energy savings, particularly for EV heating.
2017-03-28
Technical Paper
2017-01-0528
Eric Miller, Arnaud Konan, Adam Duran
Powertrain modeling is an invaluable tool for exploring energy saving potential in commercial vehicles. A robust, automated method to estimate parameters for these models can accelerate the pace of model development and calibration, while enriching existing data sets. A Bayesian technique to estimate mass, drag coefficient, rolling resistance and other vehicle characteristics was developed. The estimates were validated using dynamometer data, then applied to recorded vehicle CAN data. Individual vehicle results and database trends are presented.
2017-03-28
Journal Article
2017-01-0086
Matteo Muratori, Jacob Holden, Michael Lammert, Adam Duran, Stanley Young, Jeffrey Gonder
Smart technologies enabling connection among vehicles and between vehicles and infrastructure as well as vehicle automation to assist human operators are receiving significant attention as means for improving road transportation systems by reducing fuel consumption – and related emissions – while also providing addition benefits through improving overall traffic safety and efficiency. For truck applications, currently responsible for nearly three-quarters of the total U.S. freight energy use and greenhouse gas (GHG) emissions, platooning has been identified as an early feature for connected and automated vehicles (CAVs) that allows for significant fuel savings and improved traffic safety and efficiency without radical design or technology changes compared to existing vehicles. We propose a rigorous statistical analysis based on a large collection of real-world U.S. class 8 truck usage data to estimate the fraction of total miles that are technically suitable for platooning.
2017-03-28
Journal Article
2017-01-0581
Stephen C. Burke, Matthew Ratcliff, Robert McCormick, Robert Rhoads, Bret Windom
In some studies a relationship has been observed between increasing ethanol content in gasoline and increased particulate matter (PM) emissions from vehicles equipped with spark ignition engines. Ethanol features a greater enthalpy of vaporization (HOV) than gasoline and is commonly used in gasoline blends. In addition to increasing HOV, ethanol also influences vaporization by altering the liquid and vapor composition throughout the distillation process. A droplet vaporization model was developed to explore ethanol’s effect on the evaporation of aromatic compounds known to be PM precursors. The evolving droplet composition is being modeled as a distillation process, with non-ideal interactions between oxygenates and hydrocarbons accounted for using UNIFAC group contribution theory. Predicted composition and distillation curves were validated by experiments.
2016-10-17
Journal Article
2016-01-2322
Michael Lance, Andrew Wereszczak, Todd J. Toops, Richard Ancimer, Hongmei An, Junhui Li, Leigh Rogoski, Petr Sindler, Aaron Williams, Adam Ragatz, Robert L. McCormick
Abstract For renewable fuels to displace petroleum, they must be compatible with emissions control devices. Pure biodiesel contains up to 5 ppm Na + K and 5 ppm Ca + Mg metals, which have the potential to degrade diesel emissions control systems. This study aims to address these concerns, identify deactivation mechanisms, and determine if a lower limit is needed. Accelerated aging of a production exhaust system was conducted on an engine test stand over 1001 h using 20% biodiesel blended into ultra-low sulfur diesel (B20) doped with 14 ppm Na. This Na level is equivalent to exposure to Na at the uppermost expected B100 value in a B20 blend for the system full-useful life. During the study, NOx emissions exceeded the engine certification limit of 0.33 g/bhp-hr before the 435,000-mile requirement.
2016-09-27
Technical Paper
2016-01-8134
Lijuan Wang, Adam Duran, Kenneth Kelly, Arnaud Koana, Michael lammert, Robert Prohaska
Abstract In this paper, researchers at the National Renewable Energy Laboratory present the results of simulation studies to evaluate potential fuel savings as a result of improvements to vehicle rolling resistance, coefficient of drag, and vehicle weight as well as hybridization for four powertrains for medium-duty parcel delivery vehicles. The vehicles will be modeled and simulated over 1,290 real-world driving trips to determine the fuel savings potential based on improvements to each technology and to identify best use cases for each platform. The results of impacts of new technologies on fuel saving will be presented, and the most favorable driving routes on which to adopt them will be explored.
2016-09-27
Journal Article
2016-01-8017
Eric Wood, Adam Duran, Kenneth Kelly
Abstract In collaboration with the U.S. Environmental Protection Agency and the U.S. Department of Energy, the National Renewable Energy Laboratory has conducted a national analysis of road grade characteristics experienced by U.S. medium- and heavy-duty trucks on controlled access highways. These characteristics have been developed using TomTom’s commercially available street map and road grade database. Using the TomTom national road grade database, national statistics on road grade and hill distances were generated for the U.S. network of controlled access highways. These statistical distributions were then weighted using data provided by the U.S. Environmental Protection Agency for activity of medium- and heavy-duty trucks on controlled access highways. The national activity-weighted road grade and hill distance distributions were then used as targets for development of a handful of sample grade profiles potentially to be used in the U.S.
2016-09-27
Journal Article
2016-01-8135
Robert Prohaska, Arnaud Konan, Kenneth Kelly, Michael Lammert
Abstract In an effort to better understand the operational requirements of port drayage vehicles and their potential for adoption of advanced technologies, National Renewable Energy Laboratory (NREL) researchers collected over 36,000 miles of in-use duty cycle data from 30 Class 8 drayage trucks operating at the Port of Long Beach and Port of Los Angeles in Southern California. These data include 1-Hz global positioning system location and SAE J1939 high-speed controller area network information. Researchers processed the data through NREL’s Drive-Cycle Rapid Investigation, Visualization, and Evaluation tool to examine vehicle kinematic and dynamic patterns across the spectrum of operations. Using the k-medoids clustering method, a repeatable and quantitative process for multi-mode drive cycle segmentation, the analysis led to the creation of multiple drive cycles representing four distinct modes of operation that can be used independently or in combination.
2016-05-16
Book
Ahmad A. Pesaran
This research focuses on the technical issues that are critical to the adoption of high-energy-producing lithium Ion batteries. In addition to high energy density / high power density, this publication considers performance requirements that are necessary to assure lithium ion technology as the battery format of choice for electrified vehicles. Presentation of prime topics includes: • Long calendar life (greater than 10 years) • Sufficient cycle life • Reliable operation under hot and cold temperatures • Safe performance under extreme conditions • End-of-life recycling To achieve aggressive fuel economy standards, carmakers are developing technologies to reduce fuel consumption, including hybridization and electrification. Cost and affordability factors will be determined by these relevant technical issues which will provide for the successful implementation of lithium ion batteries for application in future generations of electrified vehicles.
2016-04-05
Technical Paper
2016-01-0230
Gene Titov, Jason Lustbader, Daniel Leighton, Tibor Kiss
Abstract The National Renewable Energy Laboratory’s (NREL’s) CoolSim MATLAB/Simulink modeling framework was expanded by including a newly developed coolant loop solution method aimed at reducing the simulation effort for complex thermal management systems. The new approach does not require the user to identify specific coolant loops and their flow. The user only needs to connect the fluid network elements in a manner consistent with the desired schematic. Using the new solution method, a model of NREL's advanced combined coolant loop system for electric vehicles was created that reflected the test system architecture. This system was built using components provided by MAHLE Inc. and included both air conditioning and heat pump modes. Validation with test bench data and verification with the previous solution method were performed for 10 operating points spanning a range of ambient temperatures between -2°C and 43°C.
2016-04-05
Technical Paper
2016-01-1190
Terry A. Johnson, Christopher Ainscough, Danny Terlip, Graham Meadows, Liam Quinlan, Brad Wong
Abstract With the introduction of more fuel cell electric vehicles (FCEVs) on U.S. roadways, especially in California, the need for available hydrogen refueling stations is growing. While funding from the California Energy Commission is helping to solve this problem, solutions need to be developed and implemented to help reduce the time to commission a hydrogen station. The current practice of hydrogen station acceptance can take months because each vehicle manufacturer conducts their own testing and evaluation. This process is not practical or sufficient to support the timely development of a hydrogen fueling station network. To address this issue, as part of the Hydrogen Fueling Infrastructure Research and Station Technology (H2FIRST) Project Sandia National Laboratories and the National Renewable Energy Laboratory along with a team of stakeholders and contractor Powertech Labs has developed the Hydrogen Station Equipment Performance (HyStEP) Device.
2016-04-05
Journal Article
2016-01-0705
Matthew A. Ratcliff, Jonathan Burton, Petr Sindler, Earl Christensen, Lisa Fouts, Gina M. Chupka, Robert L. McCormick
Abstract Several high octane number oxygenates that could be derived from biomass were blended with gasoline and examined for performance properties and their impact on knock resistance and fine particle emissions in a single cylinder direct-injection spark-ignition engine. The oxygenates included ethanol, isobutanol, anisole, 4-methylanisole, 2-phenylethanol, 2,5-dimethyl furan, and 2,4-xylenol. These were blended into a summertime blendstock for oxygenate blending at levels ranging from 10 to 50 percent by volume. The base gasoline, its blends with p-xylene and p-cymene, and high-octane racing gasoline were tested as controls. Relevant gasoline properties including research octane number (RON), motor octane number, distillation curve, and vapor pressure were measured. Detailed hydrocarbon analysis was used to estimate heat of vaporization and particulate matter index (PMI). Experiments were conducted to measure knock-limited spark advance and particulate matter (PM) emissions.
2016-04-05
Journal Article
2016-01-0836
C. Scott Sluder, James P. Szybist, Robert L. McCormick, Matthew A. Ratcliff, Bradley T. Zigler
Abstract The latent heat-of-vaporization (HoV) of blends of biofuel and hydrocarbon components into gasolines has recently experienced expanded interest because of the potential for increased HoV to increase fuel knock resistance in direct-injection (DI) engines. Several studies have been conducted, with some studies identifying an additional anti-knock benefit from HoV and others failing to arrive at the same conclusion. Consideration of these studies holistically shows that they can be grouped according to the level of fuel octane sensitivity variation within their fuel matrices. When comparing fuels of different octane sensitivity significant additional anti-knock benefits associated with HoV are sometimes observed. Studies that fix the octane sensitivity find that HoV does not produce additional anti-knock benefit. New studies were performed at ORNL and NREL to further investigate the relationship between HoV and octane sensitivity.
2016-04-05
Journal Article
2016-01-0885
Earl Christensen, Robert L. McCormick, Jenny Sigelko, Stuart Johnson, Stefan Zickmann, Shailesh Lopes, Roger Gault, David Slade
Abstract Adoption of high-pressure common-rail (HPCR) fuel systems, which subject diesel fuels to higher temperatures and pressures, has brought into question the veracity of ASTM International specifications for biodiesel and biodiesel blend oxidation stability, as well as the lack of any stability parameter for diesel fuel. A controlled experiment was developed to investigate the impact of a light-duty diesel HPCR fuel system on the stability of 20% biodiesel (B20) blends under conditions of intermittent use and long-term storage in a relatively hot and dry climate. B20 samples with Rancimat induction periods (IPs) near the current 6.0-hour minimum specification (6.5 hr) and roughly double the ASTM specification (13.5 hr) were prepared from a conventional diesel and a highly unsaturated biodiesel. Four 2011 model year Volkswagen Passats equipped with HPCR fuel injection systems were utilized: one on B0, two on B20-6.5 hr, and one on B20-13.5 hr.
2016-04-05
Journal Article
2016-01-0258
Jason Aaron Lustbader, Bidzina Kekelia, Jeff Tomerlin, Cory J. Kreutzer, Skip Yeakel, Steven Adelman, Zhiming Luo, John Zehme
Abstract Annual fuel use for sleeper cab truck rest period idling is estimated at 667 million gallons in the United States, or 6.8% of long-haul truck fuel use. Truck idling during a rest period represents zero freight efficiency and is largely done to supply accessory power for climate conditioning of the cab. The National Renewable Energy Laboratory’s CoolCab project aims to reduce heating, ventilating, and air conditioning (HVAC) loads and resulting fuel use from rest period idling by working closely with industry to design efficient long-haul truck thermal management systems while maintaining occupant comfort. Enhancing the thermal performance of cab/sleepers will enable smaller, lighter, and more cost-effective idle reduction solutions. In addition, if the fuel savings provide a one- to three-year payback period, fleet owners will be economically motivated to incorporate them.
2016-04-05
Journal Article
2016-01-0262
Matthew A. Jeffers, Larry Chaney, John P. Rugh
Abstract When operated, the cabin climate control system is the largest auxiliary load on a vehicle. This load has significant impact on fuel economy for conventional and hybrid vehicles, and it drastically reduces the driving range of all-electric vehicles (EVs). Heating is even more detrimental to EV range than cooling because no engine waste heat is available. Reducing the thermal loads on the vehicle climate control system will extend driving range and increase the market penetration of EVs. Researchers at the National Renewable Energy Laboratory have evaluated strategies for vehicle climate control load reduction with special attention toward grid-connected electric vehicles. Outdoor vehicle thermal testing and computational modeling were used to assess potential strategies for improved thermal management and to evaluate the effectiveness of thermal load reduction technologies. A human physiology model was also used to evaluate the impact on occupant thermal comfort.
2016-03-14
Journal Article
2016-01-9072
Janet Yanowitz, Robert L. McCormick
Abstract Spark-ignition engine fuel standards have been put in place to ensure acceptable hot and cold weather driveability (HWD and CWD). Vehicle manufacturers and fuel suppliers have developed systems that meet our driveability requirements so effectively that drivers overwhelmingly find that their vehicles reliably start up and operate smoothly and consistently throughout the year. For HWD, fuels that are too volatile perform more poorly than those that are less volatile. Vapor lock is the apparent cause of poor HWD, but there is conflicting evidence in the literature as to where in the fuel system it occurs. Most studies have found a correlation between degraded driveability and higher dry vapor pressure equivalent or lower TV/L = 20, and less consistently with a minimum T50. For CWD, fuels with inadequate volatility can cause difficulty in starting and rough operation during engine warmup.
2015-09-29
Technical Paper
2015-01-2739
Sean Lopp, Eric Wood, Adam Duran
Abstract Commercial vehicle fuel economy is known to vary significantly with both positive and negative road grade. Medium- and heavy-duty vehicles operating at highway speeds require incrementally larger amounts of energy to pull heavy payloads up inclines as road grade increases. Non-hybrid vehicles are unable to recapture energy on descent and lose energy through friction braking. While the on-road effects of road grade are well understood, the majority of standard commercial vehicle drive cycles feature no road grade requirements. Additionally, the existing literature offers a limited number of sources that attempt to estimate the on-road energy implications of road grade in the medium- and heavy-duty space. This study uses real-world commercial vehicle drive cycles from the National Renewable Energy Laboratory's Fleet DNA database to simulate the effects of road grade on fuel economy across a range of vocations, operating conditions, and locations.
2015-09-29
Technical Paper
2015-01-2773
Lijuan Wang, Kenneth Kelly, Kevin Walkowicz, Adam Duran
Abstract The National Renewable Energy Laboratory's (NREL's) Fleet Test and Evaluations team recently conducted chassis dynamometer tests of a class 8 conventional regional delivery truck over the Heavy Heavy-Duty Diesel Truck (HHDDT), West Virginia University City (WVU City), and Composite International Truck Local and Commuter Cycle (CILCC) drive cycles. A quantitative study analyzed the impacts of various factors on fuel consumption (FC) and fuel economy (FE) by modeling and simulating the truck using NREL's Future Automotive Systems Technology Simulator (FASTSim). Factors included vehicle weight and the coefficients of rolling resistance and aerodynamic drag. Simulation results from a single parametric study revealed that FC was approximately a linear function of the weight, coefficient of aerodynamic drag, and rolling resistance over various drive cycles.
2015-09-29
Technical Paper
2015-01-2812
Lijuan Wang, Adam Duran, Jeffrey Gonder, Kenneth Kelly
Abstract This paper presents multiple methods for predicting heavy/medium-duty vehicle fuel consumption based on driving cycle information. A polynomial model, a black box artificial neural net model, a polynomial neural network model, and a multivariate adaptive regression splines (MARS) model were developed and verified using data collected from chassis testing performed on a parcel delivery diesel truck operating over the Heavy Heavy-Duty Diesel Truck (HHDDT), City Suburban Heavy Vehicle Cycle (CSHVC), New York Composite Cycle (NYCC), and hydraulic hybrid vehicle (HHV) drive cycles. Each model was trained using one of four drive cycles as a training cycle and the other three as testing cycles. By comparing the training and testing results, a representative training cycle was chosen and used to further tune each method.
2015-04-14
Technical Paper
2015-01-1708
Tibor Kiss, Jason Lustbader, Daniel Leighton
Abstract Electric vehicles (EVs) need highly optimized thermal management systems to improve range. Climate control can reduce vehicle efficiency and range by more than 50%. Due to the relative shortage of waste heat, heating the passenger cabin in EVs is difficult. Cabin cooling can take a high portion of the energy available in the battery. Compared to internal combustion engine-driven vehicles, different heating methods and more efficient cooling methods are needed, which can make EV thermal management systems more complex. More complex systems typically allow various alternative modes of operation that can be selected based on driving and ambient conditions. A good system simulation tool can greatly reduce the time and expense for developing these complex systems. A simulation model should also be able to efficiently co-simulate with vehicle simulation programs, and should be applicable for evaluating various control algorithms.
2015-04-14
Technical Paper
2015-01-1688
Eric Wood, Jeremy S. Neubauer, Evan Burton
Abstract With support from the U.S. Department of Energy's Vehicle Technologies Office, the National Renewable Energy Laboratory developed BLAST-V-the Battery Lifetime Analysis and Simulation Tool for Vehicles. The addition of high-resolution spatial-temporal travel histories enables BLAST-V to investigate user-defined infrastructure rollouts of publically accessible charging infrastructure, as well as quantify impacts on vehicle and station owners in terms of improved vehicle utility and station throughput. This paper presents simulation outputs from BLAST-V that quantify the utility improvements of multiple distinct rollouts of publically available Level 2 electric vehicle supply equipment (EVSE) in the Seattle, Washington, metropolitan area. Publically available data on existing Level 2 EVSE are also used as an input to BLAST-V. The resulting vehicle utility is compared to a number of mock rollout scenarios.
2015-04-14
Technical Paper
2015-01-1687
Eric Wood, Jeremy S. Neubauer, Evan Burton
Abstract The disparate characteristics between conventional (CVs) and battery electric vehicles (BEVs) in terms of driving range, refill/recharge time, and availability of refuel/recharge infrastructure inherently limit the relative utility of BEVs when benchmarked against traditional driver travel patterns. However, given a high penetration of high-power public charging combined with driver tolerance for rerouting travel to facilitate charging on long-distance trips, the difference in utility between CVs and BEVs could be marginalized. We quantify the relationships between BEV utility, the deployment of fast chargers, and driver tolerance for rerouting travel and extending travel durations by simulating BEVs operated over real-world travel patterns using the National Renewable Energy Laboratory's Battery Lifetime Analysis and Simulation Tool for Vehicles (BLAST-V). With support from the U.S.
2015-04-14
Technical Paper
2015-01-1196
Jeremy S. Neubauer, Eric Wood
Abstract Fast charging is attractive to battery electric vehicle (BEV) drivers for its ability to enable long-distance travel and to quickly recharge depleted batteries on short notice. However, such aggressive charging and the sustained vehicle operation that results could lead to excessive battery temperatures and degradation. Properly assessing the consequences of fast charging requires accounting for disparate cycling, heating, and aging of individual cells in large BEV packs when subjected to realistic travel patterns, usage of fast chargers, and climates over long durations (i.e., years). The U.S. Department of Energy's Vehicle Technologies Office has supported the National Renewable Energy Laboratory's development of BLAST-V-the Battery Lifetime Analysis and Simulation Tool for Vehicles-to create a tool capable of accounting for all of these factors. We present on the findings of applying this tool to realistic fast charge scenarios.
Viewing 1 to 30 of 188

Filter

  • Range:
    to:
  • Year: