Pure Battery Electric Vehicles Research Articles

Assessing the Cross-Sectoral Economic–Energy–Environmental Impacts of Electric-Vehicle Promotion in Taiwan

Few studies have examined the cross-sectoral impacts of electric vehicles on the economy, energy, and the environment. This study adopted hybrid electric vehicles, plug-in hybrid electric vehicles, and pure-battery electric vehicles as research objects in establishing an input–output analysis framework of the electric-vehicle industry. Learning curves and scenario analysis were also used to explore the cross-sectoral economic–energy–environmental impacts of electric-vehicle promotion, using Taiwan as a case study. Our results indicated that by 2040, electric vehicles will create an output value of 157~186.7 billion NTD, while boosting employment and reducing energy expenditures but having a negligible impact on income. It is expected that by 2040, the adoption of electric vehicles will reduce energy consumption to 65~82% of the levels required for vehicles using internal-combustion engines. Electric vehicles are expected to reduce CO2 and NOX emissions but increase PM2.5 emissions, with little effect on SOX emissions.

Impact of cost-optimized dedicated hybrid transmission (DHT) constraints on powertrain optimal control

In the transition from internal combustion engines (ICE) based vehicles to pure battery electric vehicles (BEVs), the powertrain is becoming increasingly electrified (xEV). Based on their capability to recuperate brake energy in the legislative test cycles, intermediate xEV vehicles are classified as mild and strong electrified vehicles. Growing xEV sales currently pave the way for the application of cost-optimized dedicated components. The B segment vehicle analyzed in this work is currently equipped with a conventional coaxial transmission, which can offer multiple power sources (combustion engine, electric machine, or hybrid) in a single shift with an additional clutch. A cost-optimized dedicated hybrid transmission (DHT) is designed by eliminating the launch clutch, synchronizers, and redundant energy travel paths to replace the coaxial transmission. The DHT requires one shift for each energy path to connect the power source to the wheels. The flexible coaxial transmission requires only a low specific number of gear shifts to drive a typical test cycle. However, the DHT has constrained energy paths, leading to a high specific number of gear shifts to drive identical test cycles when applied with the standard Adaptive Equivalent Consumption Minimization Strategy (A-ECMS) optimal control. A one dimensional closed-loop simulation model for the passenger car longitudinal dynamics is used in this analysis. The vehicle velocity and evaluation criteria for the simulation are based on the Worldwide harmonized Light vehicles Test Procedure (WLTP). The loss maps from steady-state test bench measurements for the internal combustion engine (ICE), the electric motor (EM), and the transmission unit are used as inputs in building the simulation model. A drivability penalty approach is introduced in the standard A-ECMS optimal control to reduce the number of gear shifts. The work analyzes the gear shift behavior and the absolute CO2 emission between the cost-optimized DHT and the existing coaxial transmission for the considered vehicle application. Detailed power flow using a Sankey diagram from different onboard vehicle sources for the cost-optimized DHT solution is included in the results section. The developed model is validated with a prototype vehicle environment on the Urban Dynamometer Driving Schedule (UDDS).

A review of fuel cell technology for commercial vehicle applications

The demanding energy storage requirements of many commercial vehicle applications are extremely difficult to meet for pure battery electric vehicles (BEVs) due to the limited energy density of batteries. Fuel cells appear to be the only viable propulsion technology that is able to meet commercial vehicle powertrain requirements with zero local greenhouse gas emissions. Since almost all fuel cell vehicles (FCVs) contain a high voltage battery, some additional complexity is introduced since the hybrid energy storage system must be sized and controlled appropriately. An understanding of the strengths and weaknesses of each system is therefore essential in FCV design. The aim of this technology review is to provide an overview of fuel cell technologies in commercial vehicle applications including assessments of alternative powertrain and fuel cell types, advantages and disadvantages of fuel cell and battery systems and the implications of these on the powertrain sizing as well as control considerations of FCVs.

A sustainable process for conversion of petrol engine vehicle to battery electric vehicle: A case study

A clean environment and sustainable society can be achieved by reducing greenhouse gas emissions, which are measured by the amount of CO2 equivalents in the air. A major part of air pollution is attributed to the exhaust expelled by automobiles which can be reduced by converting existing vehicles to pure battery electric vehicles (BEV). This paper presents the process to convert a petrol-based vehicle (624 cc petrol engine vehicle) to a pure BEV suitable for the Indian automotive sector, aimed at minimizing the cost of conversion and operating cost of the vehicle. The main components used in the conversion of the vehicle are presented and their overall placement is also detailed in the paper. A three-phase brushless DC motor is used with a custom-made Li-ion battery pack along with a motor controller to realize the conversion. While carrying out the conversion process, the coupling of the motor to the gearbox was observed to be a complex task. Additionally, the development of a fool-proof circuit for effective control was observed to be a challenging task too. To tackle the circuitry issue, a novel circuitry was developed to make the connections between the motor, controller, and subsidiary parts for highly efficient vehicle operations. The prototype of the proposed conversion was also developed and tested for regular warehouse applications.

Microsimulation of electric vehicle energy consumption and driving range

In order to predict and study the effects of different parameters on performance characteristics of electric vehicles. A vehicle simulation model of pure battery electric vehicles equipped with single pedal control system is established and calibrated by the experimental data based on vehicle energy flow and driving range analysis, the simulation doesn’t include thermal aspect of the battery/vehicle. Next, the effects of different environmental and control parameters on energy consumption and driving range of pure electric vehicles are analyzed. The main findings are: (1) for the single driving cycle, the relative error of battery power and current is below 5%, and the absolute error of battery voltage is below 2.5 V. For the whole driving range, the absolute error of driving range is only about 5.75 km. (2) The main factors influencing energy consumption and driving range are average vehicle speed, running time and the frequency distribution of braking process, besides, the energy consumption of congested traffic with/without regenerative brake control system are 46.07 kW·h/100 km and 47.19 kW·h/100 km, respectively, meanwhile, vehicle with regenerative braking saves 2.43% energy under congested traffic. (3) The threshold of quitting the working condition of energy recovery for the motor can be set in a certain value based on the safety of driver in the emergencies and energy conversion. Further, the model and data in the paper can be applied to evaluate and optimize the energy consumption and driving range by changing different technologies or strategies in the future.

Examination on Classification of EVs and Energy Management Strategies of HEV

In recent days, the demand for petroleum and emission of pollutant gases continuously increase. This necessitates the electrification power train which replaces Internal Combustion Engine (ICE). Despite pure electric vehicles or Battery Electric Vehicle (EV) reduce the greenhouse gas emissions, there are some major hurdles for EVs to overcome before they totally relieve ICE vehicles form transport sector such as range anxiety, battery storage, economic fall down due to automobile industries, etc. This necessitates Hybrid Electric vehicle (HEV) which combines two different power sources to propel the vehicle. One of the challenges in HEV is how to control the power coming from the two different sources such as battery and ICE. The prime goal of an Energy Management Strategy (EMS) is to manage energy flow such that fuel consumption and emissions are minimized without affecting the vehicle’s performance. In this paper, the different structures of power train and energy management strategies are analysed.

A study on opportune reduction in greenhouse gas emissions via adoption of electric drive vehicles in light duty vehicle fleets

Electrified powertrain vehicles have the potential to bring about significant reductions in greenhouse gas (GHG) emissions in light-duty vehicle fleets as they replace conventional vehicles. Compared to electrified powertrains, a conventional vehicle (CV), whose driving power only comes from an internal combustion engine (ICE), is in many ways disadvantaged when in driven in conditions that involve frequent stops or idling. As a result, the amount of achievable reduction in GHG by replacing a CV with one that has an electrified powertrain can vary significantly depending on the driving patterns in which the vehicle is expected to be driven in. This work analyzes more than 65 thousand real-world trips from California household travel survey (CHTS) in order to highlight and quantify the differential benefit in opportune reduction of GHG emissions. Equivalent GHG emissions are estimated using a public-domain fuel economy simulations software for each trip if it was done on a mid-sized CV, a matching hybrid-electric vehicle (HEV), two different all-electric range (AER) plug-in hybrid electric vehicles (PHEVs), as well as a pure battery-electric vehicle (BEV). A clustering approach is used to discern sub-populations of vehicle samples in CHTS data set into four vehicle groups, ordered from least to most city-like driving patterns. Results show that replacing a CV in the group with city-like driving could reduce the GHG emissions by appreciably larger amounts (approx. two to three times) than in the group with less city-like driving.

Electric vehicles: solution or new problem?

Since electric vehicles (EVs) have been recognized as a technology that reduces local air pollution while improving transport energy security, they have been promoted in many countries. Yet, mainly due to their high costs, especially in the case of pure battery electric vehicles, and a lack of proper infrastructure, the use of EVs is still very limited. In this paper, some of the major barriers and the future challenges are discussed. The current problems are mainly attributed to two categories: (1) the battery performances and costs, as well as battery production including issue of material availability and (2) environmental benefits of EVs depending on the sources used for the electricity generation and their carbon intensity. The major conclusions are that (1) research and development with respect to batteries has by far the highest priority and (2) it has to be ensured that the electricity used in EVs is generated largely from renewable energy sources.

Grid Load Contributions Through Electric Vehicles and Their Uncertainties

With the numbers of electric vehicles on the increase, their additional electricity demand can no longer be neglected. From a power systems’ perspective, it is the time dependent electricity consumption that matters. In particular, the peak demand is increased in the case of uncontrolled charging, imposing additional stress on the system. Unfortunately, since there is an absence of representative electric vehicle driving patterns, a quantification of such temporal charging requirements is challenging. To overcome this problem, we developed a detailed model, which maps combustion engine vehicles onto electric vehicle equivalents. The model’s main strengths are the consideration of the diversity within the vehicle fleet as well as the differentiation into the boundary cases of pure battery electric vehicles and plug-in hybrid electric vehicles. Applied to a German traffic study, load curves for these two cases were generated. In addition, the existing uncertainty in between was quantified using Monte Carlo method. We show that the peak energy demand through electric vehicles is much greater on working days than on weekend days. Moreover, we find that the distinction between pure and plug-in-hybrid electric vehicles matters, at least for the time being. Apart from the numerical results, the model is well suited to generate input for more sophisticated investigations of charging strategies within energy system simulations.

How might potential future plug-in electric vehicle buyers differ from current “Pioneer” owners?

The entry of various plug-in electric vehicles (PEVs) into the passenger vehicle sector provides novel opportunities to learn about the potential for future PEV markets. However, early PEV buyers (or “Pioneers”) can substantially differ from present conventional vehicle owners that have interest in purchasing PEVs in the future (or the “Potential Early Mainstream buyers”). To compare the characteristics, preferences, and motivations of Pioneers and Potential Early Mainstream buyers, we draw data from the Canadian Plug-in Electric Vehicle Study, a three-part mixed-mode survey with samples of PEV owners (n=94) and conventional new vehicle buyers (n=1754). We identify several significant differences in household characteristics, including income, education, and recharge access. In terms of preferences, Pioneers express extremely high valuation of PEVs and prefer pure battery electric vehicle (BEV) designs over plug-in hybrid electric (PHEV) designs. In contrast, Potential Early Mainstream respondents prefer PHEVs. Both Pioneer and Potential Early Mainstream respondents are similarly cautious about controlled charging programs, but Pioneers place five times as much value on using electricity generated from renewable sources than the Potential Early Mainstream. Pioneers also tend to have different motivations, including significantly higher levels of environmental concern, and higher engagement in environment- and technology-oriented lifestyles. Policymakers, automakers, and electric utilities that anticipate a transition to electric mobility ought to consider how potential future PEV buyers may differ in their vehicle preferences, usage and motivations relative to current PEV owners.

Acceleration-based design of electric vehicle auxiliary energy source

The battery electric vehicle (BEV) has disadvantages of high power loss during acceleration and poor regenerative braking energy recapture. Moreover, the battery is frequently exposed to repetitive high power demand, which consequently shortens the battery lifetime [1]. To overcome these problems, many parallel connections of energy sources have been proposed by scientists with the aim to reduce high peak power supply and repetitive power, as well as to save battery energy and lengthen its use [2], [3]. In this article, a parallel supercapacitors (SCs)- batteries scheme for battery hybrid electric vehicle (BHEV) and its control are proposed. The configuration consists of a parallel connection of batteries and SCs, which are connected to the inverter via a bidirectional dc-dc converter, as shown in Figure 1. This scheme intends to save braking energy for extending the driving range. In order to control the voltage and current of SCs, the control algorithms, composed of cascaded voltage and current loops based on the acceleration-based design (ABD), are developed. For efficiency validation, comparison of the core features between 3 different system configurations are proposed: the proposed BHEV with acceleration-based design (BHEV-ABD), BHEV with load-based design (BHEV-LBD) [4], and a pure BEV.

Does Transport Behavior Influence Preferences for Elektromobility? An Analysis Based on Person- and Alternative-Specific Error Components

The interconnection among different choices by the same decision-maker is fairly well established in the literature. Along this line, this paper aims to identify how preferences for electromobility are affected by mode choices for regular trips. With this purpose in mind, a framework based on person- and alternative-specific error components (covariances) is proposed. The method aims to include individual-specific error components associated with the alternatives of a given experiment into another, and to analyze how the preference for a certain alternative in a given choice situation affects the individual’s preferences in another choice situation. The data for the analysis originates from two discrete choice experiment conducted in Austria during February 2013 (representative sample). Here, individuals were asked to state their preferences in the contexts of transport mode choice and vehicle purchase situations. The results indicate the existence of a strong correlation between the individuals’ preferences in both experiments. This way, individuals favoring private transport also favor conventional vehicles over electric alternatives, while individuals preferring public or non-motorized modes ascribe a higher utility to electric vehicles, especially to pure battery electric vehicles.

Operational efficiency comparison on eco-friendly vehicles including dynamic wireless charging

Eco-friendly vehicle technologies for commercial bus applications, such as a plug-in series-hybrid electric vehicle (SHEV), a pure battery electric vehicle (BEV), and an electric vehicle (EV) with dynamic wireless charging electric vehicle (DWEV), are analyzed in view of operational efficiency by calculating the optimized energy consumption from simulation based upon derived specifications of each power drive system. By developing proper vehicle driving modelling and controllers to achieve the required performances of different types of commercial buses, energy consumption and efficiency analysis over NY Manhattan (NY), the High Speed Heavy Duty Diesel Truck (HHDT), and the actual measured ‘on-campus’ drive cycles are performed for equivalent and practical comparison. Typical driving behaviors, vehicle headways, and dynamic wireless charging phenomena associated with the on-board battery energy capacity are considered. For DWEV, several different schemes of installing an on-road powered track for stationary and dynamic on-road charging are compared. The overall operational efficiency of the BEV and the DWEV, in view of energy cost, showed higher than that of the SHEV. Compared with the baseline CNG-engine bus, the energy consumption reductions, in view of energy cost, were found to be 10% for the SHEV, 60% for the BEV, and 65% for the DWEV.

Adsorbed methane storage for vehicular applications

Abstract The methane storage properties of five benchmark high surface area adsorbent materials were studied at ambient temperature and up to 250 bar service pressure. Using adsorption and sample density data, we evaluated the potential of these materials to store methane in a 110 L pressure vessel. At 50 bar, the adsorbent materials significantly outperformed traditional compressed gas storage. Two materials, an activated carbon and a copper based metal–organic framework (Cu-BTC), also showed improvement over compressed gas storage at 250 bar. Driving ranges calculated from storage data show that with an adsorbent, a 110 L tank filled to 50 bar could have a driving range of up to 140 miles, more than three times the range offered by a plug-in hybrid electric vehicle when operating as a pure battery electric vehicle.

Comparative Study of Different Energy Management Strategies for Dual-Source Electric Vehicles

This paper presents a comparative analysis between a pure battery electric vehicle and a dual-source electric vehicle endowed with a multi-level energy management strategy. The energy management of multi-source electric vehicles is a crucial aspect to obtain an effective contribution of the power sources, namely one with high specific energy and another with high specific power. This issue is particularly relevant for electric vehicles subject to high accelerations, breaking and those performing a large number of start and stop in its driving cycle. A comprehensive energy management system architecture with different management levels is presented and compared with a rule-based strategy (power disaggregation) and a pure battery electric vehicle. Simulations have been performed for two different urban driving cycles (NYCC and ARTEMIS low power urban) in order to validate and compare the effectiveness of the strategies under study. The results obtained show the usefulness of the proposed multi-level energy management strategy based on an integrated rule-based meta-heuristic approach versus an energy management strategy directed by the power disaggregation concept. The proposed approach increases the electric vehicle performance due to a better usage of the sources, which leads to a reduced installed power capacity.

Why electric vehicles failed

China, Europe, Japan, and the US started with large public programs more than five years ago to make electric passenger cars popular. While China’s government aimed to create a strong Chinese car industry by leapfrogging to electric vehicles, Europe, the US, and Japan tried to compete with China, wanted to decrease the dependency on oil imports and to reduce \(\mathrm{{CO}}_{2}\) emissions from transportation. Today, we realize that all programs failed and electric vehicles are going to flop. One reason for that is insufficient information to customers. The article analyzes the acceptance of electric vehicles via an experimental design with comprehensive test drives. For the experiment, eleven plug-in electric vehicles were tested by 232 customers. The analysis is based on the Technology Acceptance Model and a literature based extension. A partial least squares approach with reflective and formative indicators was chosen as method. The main result of this study is that acceptance patterns change through increasing experience with the new product. For that, possibilities to test an innovation are absolutely essential. Electric vehicles can become part of the evoked set of new car buyers, if the customer is provided by sufficient individual information. Additionally, it is recommended to support the marketing of plug-in hybrids or range extended electric cars due to psychological concerns about the limited range of pure battery electric vehicles.

Optimal power management for fuel cell–battery full hybrid powertrain on a test station

In this study, a test station of fuel cell–battery hybrid powertrain is established for validating the control strategy and system components as a Hardware-in-the-Loop test platform. Firstly, a fuel cell and LiFeO4 battery pack full hybrid powertrain is presented and the structure and methods of the module-based test station are described. Secondly, a power management strategy is proposed for the hybrid powertrain, aiming to minimize the hydrogen consumption of the fuel cell stack with a limited power rising rate and meanwhile to obtain a given depleting value for the state of charge (SOC) of the battery pack over the ECE driving cycle. The strategy has been implemented in the Matlab/Simulink software and its effectiveness is evaluated by the simulation results and experimental data from the test station. Finally, it is deduced that the proposed fuel cell–battery full hybrid powertrain can bring about greater improvements in driving range than pure battery electric vehicle. Thus, it is confirmed that the full hybrid structure and optimal control scheme can be used to achieve specific objectives for fuel cell–battery hybrid powertrains.

Development of electric vehicles use in China: A study from the perspective of life-cycle energy consumption and greenhouse gas emissions

China has promoted the use of electric vehicles vigorously since 2009; the program is still in its pilot phase. This study investigates the development of electric vehicle use in China from the perspectives of energy consumption and greenhouse-gas (GHG) emissions. Energy consumption and GHG emissions of plug-in hybrid electric vehicles (PHEVs) and pure battery electric vehicles (BEVs) are examined on the level of the regional power grid in 2009 through comparison with the energy consumption and GHG emissions of conventional gasoline internal combustion engine vehicles. The life-cycle analysis module in Tsinghua-LCAM, which is based on the GREET platform, is adopted and adapted to the life-cycle analysis of automotive energy pathways in China. Moreover, medium term (2015) and long term (2020) energy consumption and greenhouse-gas emissions of PHEVs and BEVs are projected, in accordance with the expected development target in the Energy Efficient and Alternative Energy Vehicles Industry Development Plan (2012–2020) for China. Finally, policy recommendations are provided for the proper development of electric vehicle use in China.

Fuel Economy and Greenhouse Gas Emissions Labeling for Plug‐In Hybrid Vehicles from a Life Cycle Perspective

SummaryFuel economy has been an effective indicator of vehicle greenhouse gas (GHG) emissions for conventional gasoline‐powered vehicles due to the strong relationship between fuel economy and vehicle life cycle emissions. However, fuel economy is not as accurate an indicator of vehicle GHG emissions for plug‐in hybrid (PHEVs) and pure battery electric vehicles (EVs). Current vehicle labeling efforts by the U.S. Environmental Protection Agency (EPA) and Department of Transportation have been focused on providing energy and environmental information to consumers based on U.S. national average data. This article explores the effects of variations in regional grids and regional daily vehicle miles traveled (VMT) on the total vehicle life cycle energy and GHG emissions of electrified vehicles and compare these results with information reported on the label and on the EPA's fuel economy Web site. The model results suggest that only 25% of the life cycle emissions from a representative PHEV are reflected on current vehicle labeling. The results show great variation in total vehicle life cycle emissions due to regional grid differences, including an approximately 100 gram per mile life cycle GHG emissions difference between the lowest and highest electric grid regions and up to a 100% difference between the state‐specific emission values within the same electric grid regions. Unexpectedly, for two regional grids the life cycle GHG emissions were higher in electric mode than in gasoline mode. We recommend that labels include stronger language on their deficiencies and provide ranges for GHG emissions from vehicle charging in regional electricity grids to better inform consumers.

Auto-electrification [hybrid electric vehicle

Petrol-free passenger cars are no longer the sole province of small specialist manufacturers. Ford is one of many car-makers planning to target the growing market for hybrid and all-electric cars. The Ford strategy calls for the introduction of new hybrids, a plug-in hybrid electric vehicle (PHEV) and battery electric vehicles (BEVs) based on two new global product platforms. The plan calls for in 2011 a pure BEV - using lithium-ion battery technology - as a passenger car in North America.