Battery Technologies For Electric Vehicles Research Articles

Heat Transfer Performance Analysis of an E-Vehicle Cooling System Using a Hybrid Peltier System

Abstract: This research investigates the heat transfer performance of an electric vehicle (EV) cooling system utilising a hybrid Peltier as integrated system with advancements in EV battery technology, the demand for efficient cooling systems has become crucial for ensuring battery safety, longevity, and overall performance. Present research focus on the application of ethylene glycol as a coolant, exploring the thermal parameters, heat transfer rates, and overall effectiveness of the hybrid cooling system. A literature review highlights the significance of heat transfer enhancement techniques, emphasising the need for energyefficient methods in the automotive industry. The research methodology involves experimental work, analytical calculations, and the preparation of coolant samples to evaluate thermo-physical parameters. The results demonstrate the temperature drop, Overall heat transfer for different flow rates, Logarithmic Mean Temperature difference, and Comparative Power Consumption of different setup. The result showed that presence of ethylene glycol in water enhances the desirable temperature drop of the heat transfer fluid. The Overall heat transfer rate is increased by 58% for EG-100 sample as compared to pure water. Further an ANN model is also developed for prediction of temperature drop, the result showed 2 layer model with 8, 8 neurons as optimum model for prediction.

Cross-national and cross-sectoral dynamics of innovation policies: The case of lithium-ion battery technology for electric vehicles in the U.S. and China

Sustainable technology increasingly relies on highly complex basic science, and basic research policies play a dominant role in the long-term process of sustainable technology innovation. The formation of socio-technological systems around green technology is closely linked to both the sustainable and industrial targets of nations. However, there is currently no formal model that encompasses various technology and cross-national sectors, which is necessary for analysing collaboration in relation to new scientific knowledge and new sustainable technology. Nevertheless, empirical evidence suggests that such a dynamic is pervasive. Our study aims to resolve this issue by developing an analytical model that integrates scientific research policy and innovation policy. We demonstrate the effectiveness of this model by analysing the cross-sectoral and cross-national dynamics of U.S. and Chinese policies for high energy density lithium-ion battery technologies essential to electric vehicles. We apply our model to the case of how China was able to emerge as a frontrunner in commercialisation despite the U.S.' early head start by way of ‘legitimate free-riding’ and ‘complex cross-sectional policy’ mechanisms. This case study enables us to formalise novel methods of analysing technological innovation over time, opening the door for application to a wide range of additional cases moving forward.

Vibration-based performance analysis between lithium-ion and lithium-polymer batteries

This study aims to determine whether lithium-ion or lithium-polymer batteries are better suited for usage in applications with high levels of vibration, such as electric vehicles, by examining their responses to vibration. Both types of batteries were subjected to vibration testing according to the International Electrotechnical Commission (IEC) 62660-2 standard for a full 24 hours at a frequency range of 10-2000 Hz. Both types of cells were put through a 10-cycle cycling test before and after vibrations, during which they were charged and discharged repeatedly. According to the findings, both types of cells display a rise in Nyquist impedance and a drop in cell capacity. However, these effects were more pronounced in lithium-ion batteries than in lithium-polymer batteries. These results show that lithium-polymer batteries may be more robust to vibrations than lithium-ion batteries, which might have substantial consequences for selecting viable battery types for use in electric vehicles. Overall, the results of this research offer significant new insights into the performance characteristics of these two different types of batteries, and they contribute to the body of information already present in the area of electric vehicle battery technology.

Advancements in Battery Technology for Electric Vehicles: A Comprehensive Analysis of Recent Developments

Numerous recent innovations have been attained with the objective of bettering electric vehicles and their components, especially in the domains of energy management, battery design and optimization, and autonomous driving. As a result, the eco-system becomes more efficient and long-lasting, and the technology for electric cars of the future is advanced. Insights into cutting-edge e-mobility research and developments, including electric cars (EVs) and other novel, inventive, and promising technologies, are provided by this study. These developments may be feasible by 2030. Digital twins that are linked to the Internet in Things (Iota) are one example of an appropriate modelling and design strategy covered in this research. Thanks to the concept of the Internet of Things, autonomous vehicles could improve road safety, fuel efficiency, and supply drivers more time for other tasks. Additionally discussed in this article is the technology that allows a vehicle to leave a parking spot, drive along a lengthy roadway, and finally park at its destination. The information gathered for use on real roads is crucial to the advancement of autonomous vehicles. Proposals for intelligent, autonomous vehicles and research needs are also present. The description includes numerous societal problems, one of which is the reason of an accident involving an autonomous car. We quickly go over a smart gadget that can detect unusual driving habits and stop accidents in their tracks. Additionally, every area of study pertaining to electric vehicles is addressed, along with the anticipated difficulties and gaps in understanding in each. This includes areas such as environmental evaluation, market research, power electronics, powertrain engineering, and power battery material sciences.

Lithium-Ion Battery Technologies for Electric Vehicles: Progress and challenges

Electric Vehicle (EV) sales and adoption have seen a significant growth in recent years, thanks to advancements and cost reduction in lithium-ion battery technology, attractive performance of EVs, governments’ incentives, and the push to reduce greenhouse gases and pollutants. In this article, we will explore the progress in lithium-ion batteries and their future potential in terms of energy density, life, safety, and extreme fast charge. We will also discuss material sourcing, supply chain, and end-of-life-cycle management as they have become important considerations in the ecosystem of batteries for the sustained growth and adoption of EVs. With significant government and private sector investments in research and development, processing, and manufacturing and advances in anodes (lithium and silicon), cathodes (high nickel), designs, supply chain development, and the circularity of lithium-ion batteries, lithium-based batteries are on track to make EVs mainstream, addressing climate concerns of fossil-fueled vehicles.

Comparative sustainability assessment of lithium-ion, lithium-sulfur, and all-solid-state traction batteries

PurposeTraction batteries are a key component for the performance and cost of electric vehicles. While they enable emission-free driving, their supply chains are associated with environmental and socio-economic impacts. Hence, the advancement of batteries increasingly focuses on sustainability next to technical performance. However, due to different system definitions, comparing the results of sustainability assessments is difficult. Therefore, a sustainability assessment of different batteries on a common basis considering the three sustainability dimensions is needed.MethodsThis paper investigates the sustainability of current and prospective traction battery technologies for electric vehicles. It provides a common base for the comparison of the predominant lithium-ion batteries with new technologies such as lithium-sulfur and all-solid-state batteries regarding the environmental and socio-economic impacts in their supply chain. A life cycle sustainability assessment of ten battery types is carried out using a cradle-to-gate perspective and consistent system boundaries. Four environmental impact categories (climate change, human toxicity, mineral resource depletion, photochemical oxidant formation), one economic performance indicator (total battery cost), and three social risk categories (child labor, corruption, forced labor) are analyzed.ResultsThe assessment results indicate that the new battery technologies are not only favorable in terms of technical performance but also have the potential to reduce environmental impacts, costs, and social risks. This holds particularly for the lithium-sulfur battery with solid electrolyte. The environmental benefits are even amplified with a higher share of renewable energy for component and battery production. Nevertheless, hotspots related to the high energy demand of production and the supply chain of the active materials remain.ConclusionsThis article emphasizes the need to evaluate different battery technologies on a common basis to ensure comparability of the results and to derive reliable recommendations. The results indicate that the lithium-sulfur battery with solid electrolyte is preferable since this battery has the best indicator scores for all impact categories investigated. However, all-solid-state batteries are still under development so that no conclusive recommendation can be made, but further development of these battery technologies appears promising.

State of Research & Development in Electric Vehicle Battery Technology

Sustainable storage solutions are crucial to achieving deep decarbonization of the transport sector in the future, and substantial investment is being poured into research and development of battery based solutions worldwide. Efforts directed at reducing battery cost, increasing energy density, improving durability and lifetime, among other improvements, are being ramped up in a bid to rapidly enhance battery performance and affordability. This report presents a summary of commercially available EV battery technologies, as well as battery research focused on developing alternative technologies, and provides recommendations on how to strengthen industry–academia collaboration in the country.

Saving global platinum demand while achieving carbon neutrality in the passenger transport sector: linking material flow analysis with integrated assessment model

Securing the supply of platinum-group metals (PGMs) is crucial for the development of fuel cell vehicles (FCV), which are among the most promising low-carbon vehicle technologies in the future. Existing research has evaluated the worldwide demand and supply of platinum-group metals in this century with bottom-up models on the competing battery technologies for electric vehicles. However, it is important to evaluate the material efficiency for emission reduction if an aggressive transition towards net-zero carbon emissions is pursued at the global scale due to the geochemical scarcity of platinum-group metals on earth. This research aims to bridge this gap by linking the material flow analysis (MFA) and a bottom-up integrated assessment model, namely, the Integrated Model of Energy, Environment and Economy for Sustainable Development (IMED|TEC). Through this cutting-edge integrated approach and taking passenger cars as a case study, we attempt to evaluate the nexus between platinum and the emission reduction in CO2 in the use phase of cars under the progressive electrification scenarios towards carbon neutrality within half a century. The results show that the uneven market penetration of battery electric vehicles and fuel cell vehicles can lead to geographical disparity in supply and demands for platinum, which will reshape the world material flows. The material efficiency for emission reduction in the use stage of cars during the progressive adoption of carbon-neutral automotive technologies highly relies on the alignment of the recycling sector with the global automobile production network. Global coordination is needed to enhance the material efficiency for rare metals in the transition towards a carbon-neutral future.

Inhibiting Li Plating on Graphite Electrodes during 4C Fast-Charging with Atomic Layer Deposition

The ability to increase the charging rate of lithium-ion batteries (LIBs) is of critical importance to the widespread commercialization of electric vehicles (EVs).1 One of the primary factors limiting the fast-charge ability of state-of-the-art LIBs is the tendency for plating out of metallic Li on the graphite electrode during charging.2 This phenomenon leads to rapid capacity fading of the cell, consumption of the electrolyte (cell drying), and the potential for short-circuit from dendrites penetrating the separator.To prevent/mitigate these effects, we implement a surface coating on post-calendared graphite anodes. To date, the vast majority of atomic layer deposition (ALD) coatings that have been investigated as electrode coatings are simple binary metal oxides that have very low ionic conductivity. This has limited the maximum usable thickness due to high impedance. In contrast, the ALD coating used in this work is a lithium borate-carbonate (LBCO) solid electrolyte film. The film has previously been shown to exhibit ionic conductivities above 2*10-6 S/cm and excellent electrochemical stability, including with Li metal.3 Full graphite-NMC 532 cells with ALD-coated graphite electrodes exhibit dramatic improvements in performance during 4C fast-charging, enabling fast-charging of high loading (>3 mAh/cm2) electrodes in 15 minutes with minimal Li plating. This resulted in >40x improvement in the cycle life to 80% capacity retention in 7x10 cm pouch cells.The cells with LBCO-coated electrodes demonstrated improved Coulombic efficiency, decreased interfacial impedance, decreased cell polarization, improved rate capability, improved cycle life, and dramatically reduced Li plating during fast charging. The properties and performance of the coating will be examined using electrochemical impedance spectroscopy (EIS), x-ray photoelectron spectroscopy (XPS), differential voltage analysis, and electron microscopy. This work represents a significant advance in the state-of-the art of electrode coatings for fast-charging of LIBs with high electrode loadings. It also demonstrates the critical role of the SEI in fast-charging, and the opportunity it presents for achieving enhanced performance. References (1) Zeng, X.; Li, M.; Abd El‐Hady, D.; Alshitari, W.; Al‐Bogami, A. S.; Lu, J.; Amine, K. Commercialization of Lithium Battery Technologies for Electric Vehicles. Adv. Energy Mater. 2019, 9 (27), 1900161. https://doi.org/10.1002/aenm.201900161.(2) Gallagher, K. G.; Trask, S. E.; Bauer, C.; Woehrle, T.; Lux, S. F.; Tschech, M.; Lamp, P.; Polzin, B. J.; Ha, S.; Long, B.; Wu, Q.; Lu, W.; Dees, D. W.; Jansen, A. N. Optimizing Areal Capacities through Understanding the Limitations of Lithium-Ion Electrodes. J. Electrochem. Soc. 2016, 163 (2), A138–A149. https://doi.org/10.1149/2.0321602jes.(3) Kazyak, E.; Chen, K. H.; Davis, A. L.; Yu, S.; Sanchez, A. J.; Lasso, J.; Bielinski, A. R.; Thompson, T.; Sakamoto, J.; Siegel, D. J.; Dasgupta, N. P. Atomic Layer Deposition and First Principles Modeling of Glassy Li3BO3-Li2CO3 Electrolytes for Solid-State Li Metal Batteries. J. Mater. Chem. A 2018, 6 (40), 19425–19437. https://doi.org/10.1039/c8ta08761j.

Higher 2nd life Lithium Titanate battery content in hybrid energy storage systems lowers environmental-economic impact and balances eco-efficiency

Energy exchange technologies will play an important role in the transition towards localised, sustainable energy supply. Hybrid energy storage systems, using different energy storage technologies, are currently under investigation to improve their technical performance and environmental sustainability. However, there is currently no exploration of the environmental benefits and economic feasibility of hybrid energy storage systems combining 1st and 2nd life batteries and battery electric vehicles. To determine the environmental and economic impacts of this type of hybrid energy storage system, this research employs a three-tier circularity assessment incorporating Life Cycle Assessment, Techno Economic Analysis and an Eco-Efficiency Index, from cradle-to-grave, of 43 techno-hybridisations of four 1st and 2nd life battery technologies; Lithium Titanate, Lead-acid, Lithium Iron Phosphate and Sodium-ion, with battery electric vehicles. The results of the life cycle assessment and techno-economic analysis show that a hybrid energy storage system configuration containing a low proportion of 1st life Lithium Titanate and battery electric vehicle battery technologies with a high proportion of 2nd life Lithium Titanate batteries minimises the environmental and economic impacts and provides a high eco-efficiency. The results of the eco-efficiency index show that a hybrid energy storage system configuration containing equal proportions of 1st and 2nd life Lithium Titanate and BEV battery technologies is the most eco-efficient. This research highlights the environmental and economic benefits of the use of Lithium Titanate battery technologies within novel hybrid energy storage systems.

Evolution of Global EV Battery Technology Based on the Main Path of Patent Citation

Based on the patent data collected from European patent database search, this paper firstly analyzes the general situation of electric vehicle battery field in terms of patent application trend, regional distribution and technology field distribution, then constructs patent citation networks in different development stages and identifies the main path of patent citations by SPC algorithm. Finally, the technological evolution process in the field of electric vehicle battery is analyzed by combining visualization mapping and patent texts. The research results show that the evolution direction of electric vehicle battery technology gradually converges, and fuel cell technology is the most critical technology in the whole technology development process.

Improvements in electric vehicle battery technology influence vehicle lightweighting and material substitution decisions

Demand for battery electric vehicles (BEVs) has grown over the past decade as a result of climate action targets and energy policies globally. To improve driving range and minimize battery costs, BEV manufacturers have adopted lightweight materials with the objective of reducing energy requirements and enabling the use of smaller, less expensive batteries. However, improvements in battery energy density and electric motor technologies have enhanced vehicle performance and lowered costs independently. Thus, the need for expensive lightweight materials for mass savings could diminish as these technologies rapidly advance. This study evaluates lightweight material substitution cost tradeoffs and their changes over time for an advanced high strength steel and aluminum BEV design. Process-based cost modeling methods assess cost tradeoffs for body and closures and mass scaling estimations inform costs in the battery and motor, chassis, and other vehicle systems. Under current conditions, a steel design costs $595 less per vehicle than aluminum, where steel’s cost advantage is in body and closures manufacturing and aluminum’s advantage is in battery, motor, and chassis manufacturing cost. As lightweighting advantages of battery and motor costs decline over time, the cost gap grows wider, with a $743 per vehicle cost advantage for steel. These results underscore the importance of accounting for technological advancements and learning when projecting BEV costs. This material substitution decision ultimately has implications for energy systems and long-term profitability of BEV business models. As BEV performance and costs improve, there will be an increase in demand for BEVs, electricity, and charging infrastructure.

Evaluation of Ageing and Degradation for Lithium-Ion Batteries By Using Electrochemical Harmonic Analysis (EHA)

Lithium-ion cells show a significant degradation in performance with time (1). This occurs as a result of physical and mechanical changes over time that impacts the electrochemical properties and operating parameters throughout the battery lifetime. These can affect the battery performance in terms of a rise in battery impedance and change in the potential difference that are known as a result of nonlinear electrochemical processes of batteries (2, 3). Therefore, the method of observing nonlinear behaviours have been outstanding to understanding and optimising battery performance (1, 3).In this research, the influences of battery ageing and degradation on harmonic distortion in lithium-ion batteries are investigated to understand nonlinear behaviours of batteries by using Electrochemical Harmonic Analysis (EHA). The study analysed the effects of wide range of temperatures, C-rates and state of charge on battery ageing and degradation. For this purpose, aged and pristine cells are tested in order to analysis harmonic distortion at a specific frequency range between 100mHz and 10kHz.The comparison of harmonic distortion at the same frequencies for aged and pristine cells illustrates that there is a relationship between ageing phenomena and harmonic distortion. The level of distortion increases proportionally according to the effects of ageing on the battery over time. The distortion was mostly seen in lower frequencies, which were in the range of 100mHz to 10Hz. This distortion proceeded directly from the diffusion process of lithium-ion cells. The findings indicate that lower levels of state of charge and higher temperatures have a decrease in total harmonic distortion (THD).The principal conclusion of this study is that the difference in the behaviour of aged and pristine cells clearly indicates that EHA technique can be used to identify the degree of ageing and degradation on lithium-ion cells. Keywords: Electrochemical Impedance Spectroscopy (EIS), Harmonic Analysis, Total Harmonic Distortion (THD), Distortion Integral (DI), Ageing, Degradation, Lithium-ion Battery, Temperature Effect, C-rates, State of Charge (SoC), State of Health (SoH). N. Harting, R. Schenkendorf, N. Wolff and U. Krewer, Applied Sciences, 8, 821 (2018).J. Vetter, P. Novák, M. R. Wagner, C. Veit, K.-C. Möller, J. Besenhard, M. Winter, M. Wohlfahrt-Mehrens, C. Vogler and A. Hammouche, Journal of power sources, 147, 269 (2005).M. Danzer, V. Liebau and F. Maglia, in Advances in Battery Technologies for Electric Vehicles, p. 359, Elsevier (2015).

Commercialization of Lithium Battery Technologies for Electric Vehicles

AbstractThe currently commercialized lithium‐ion batteries have allowed for the creation of practical electric vehicles, simultaneously satisfying many stringent milestones in energy density, lifetime, safety, power, and cost requirements of the electric vehicle economy. The next wave of consumer electric vehicles is just around the corner. Although widely adopted in the vehicle market, lithium‐ion batteries still require further development to sustain their dominating roles among competitors. In this review, the authors survey the state‐of‐the‐art active electrode materials and cell chemistries for automotive batteries. The performance, production, and cost are included. The advances and challenges in the lithium‐ion battery economy from the material design to the cell and the battery packs fitting the rapid developing automotive market are discussed in detail. Also, new technologies of promising battery chemistries are comprehensively evaluated for their potential to satisfy the targets of future electric vehicles.

All-Climate Battery Technology for Electric Vehicles: Inching Closer to the Mainstream Adoption of Automated Driving

The year 2017 was when electric vehicles (EVs) came of age. EV sales, according to Macquarie Bank, climbed from 740,000 vehicles in 2016 to 1.1 million, an increase of 51%. In terms of market shares, EVs accounted for 1.7% of new car sales in 2017, up from 1.1% in 2016. Although still small in the grand scheme of things, the growth rate was exceptional. All market movers are now taking EVs seriously, as evidenced by a flurry of announcements last year about the plans of major automakers for the EV market. Should these plans come to fruition, we are foreseeing roughly 400 models and 25 million sales of EVs by 2025.

Selection of Lithium-ion Battery Technologies for Electric Vehicles under China’s New Energy Vehicle Credit Regulation

Electric vehicle, as the most promising innovative solution for energy transition, has gained high priority globally. The newly issued Chinese new energy vehicle (NEV) credit regulation is expected to have a dramatic impact on the development of Chinese and even global electric vehicle market as well as energy structure. This paper focuses on the development of Li-ion batteries for electric vehicles under the regulation and establishes a bottom-up model to compare different batteries from the perspective of credit cost-effectiveness. The results suggest that small BEVs will always have the highest credit cost-effectiveness and midsize BEVs can obtain the highest credit quickly before 2020. As for different Li-ion batteries, the LFP battery is losing superiority compared to NCM batteries, and the NCA battery is slightly inferior to NCM811 because of the technical difficulties through 2020. Under the guidance of policies, the larger the vehicle and AER, the higher nickel batteries will be applied. It’s predictable that with the rapid development of batteries, the credit cost-effectiveness will be higher and higher. Moreover, the capacity of high nickel batteries will continue to expand, which will have a great influence on the demand and price of different materials.

Thermal-Mechanical-Electrochemical Coupling Simulation for Electric Vehicle Batteries

The major trend toward vehicle electrification intensifies the need for increased battery energy densities. During the development of new electric vehicle battery technologies, it has become clear that thermal, mechanical, and electrochemical coupling effects play an important role in battery performance, degradation, and response to abusive conditions. The macro-homogeneous Dualfoil model, which solves ion transport and charge transfer dynamics, predicts the electrical response of a single small battery cell. However, when considering large cells or assembled battery modules and packs, inhomogeneity of electric potential and temperature throughout the cell volume becomes severe enough to impact battery performance. Cell expansion and contraction during charge/discharge cycles further increase such inhomogeneity, and the resulting potential and temperature imbalances cause non-uniform current distribution in the cell. Heavily cycled cell regions generate additional heat and stress, causing severe degradation in the performance and life of the battery. Given the strong coupling between thermal, mechanical, and electrochemical phenomena, it is imperative to integrate multiple physical models in the simulation of complete battery packs. In this work, a modified Dualfoil electrochemical model is coupled to a thermo-mechanical finite element solver to represent such multiphysics coupling effects. Outputs from the 3D thermo-mechanical solver, such as temperature and stress, are supplied as inputs to the Dualfoil model, which in return computes the electrochemical response and provides the local heat generation rate and Li intercalation induced volume change to the thermo-mechanical solver. Using this coupled multiphysics simulation framework, the impact of external mechanical loading under different charge/discharge profiles was investigated. The transient, non-linear behavior of internal variables, such as SOC, overpotential, and current density, during and after cycles, was obtained in the entire 3D battery pack domain. This information provides good insights for design and optimization of battery packs with high performance and long life time.

Dynamic Chemical X-Ray Microscopy on Energy Storage Materials

The shift from fossil fuels toward clean, renewable energy will require significant improvements in rechargeable battery technology for electric vehicles. Current battery technology limits electric vehicles to a short travel range, slow recharge, and costly price tag. Li-ion batteries promise the high specific capacity required to replace the internal combustion engine with a number of possible earth abundant electrode materials; however, setbacks such as capacity fading hinder the full capability of these rechargeable batteries. In the search for better electrode materials, high resolution chemical imaging during typical battery operation is vital in understand and overcoming the failure mechanisms of these materials. By combining X-ray absorption spectroscopy with high resolution, hard X-ray transmission microscopy (TXM), we have tracked the chemical changes of electrode material in real time during typical battery operation (Figure). [1, 2] We will discuss recent results tracking electrochemical and morphological changes in cathode materials during cycling, including LiFePO4,[3] LiCoO2, and Li2Cu0.5Ni0.5O2. Finally, we will discuss how ptychography, an emerging X-ray microscopy technique that promises sub-5 nm resolution, has the potential to image batteries during cycling at resolutions that rival in situ TEM with liquid cells. [1] J.N. Weker, X. Huang, M.F. Toney, 2 (2016) 14-21. [2] J. Nelson Weker, M.F. Toney, Advanced Functional Materials, 25 (2015) 1622-1637. [3] J. Nelson Weker, Y. Li, R. Shanmugam, W. Lai, W.C. Chueh, ChemElectroChem, 2 (2015) 1576-1581. Figure 1

Technology Forecast for Electrical Vehicle Battery Technology and Future Electric Vehicle Market Estimation

Electric Vehicle (EV) battery technologies is a limiting factor for the wide spread diffusion of electric vehicles. EV battery’s energy density compared to fossil fuels is still very low, thus EV’s have still stringent driving range with voluminous, heavy and high cost batteries. Automotive OEM’s are trying to estimate the future of batteries to do their plans related to electric vehicle manufacturing. This article attempts to estimate the future of EV batteries and mainly that of Li_Ion, Li_S and Li_Air Technologies which seem to be the most promising Technologies as of today. The article explains in detail the methodology used, and the results with an estimation of future EV market as a result of the EV battery development time scale.

A three-stage decision-making model for selecting electric vehicle battery technology

This study proposes a three-stage decision-making model for the selection of electric vehicle battery technology. Data used for analysis include surveys completed by 45 technology experts from industry, academia, and research throughout Taiwan. A three-stage model that includes developing multiple-criteria during the first stage, integrating the importance of criteria assessment using the fuzzy analytical hierarchy process in the second stage, and using patent analysis tools to further identify the patent portfolio of the technology selected by experts in the third stage are employed. The empirical results indicate that power source management technology and battery module technology are the key technologies for development by the electric vehicle industry. Battery energy storage management and cooling technology are found to be the key for building patent portfolios. When faced with substantial technical and market uncertainty, multiple-criteria for research and development (R&D) selection and stage-wise integration of decision tool must be employed by battery firms to effectively allocate the resources for R&D decisions.