High Performance Electric Vehicle Research Articles

Efficient tuning of active sound design in electric vehicles - An interactive validation approach

The implementation of active sound design models in a target vehicle requires careful tuning of all synthetic sound elements with respect to existent vehicle interior noise, current driving conditions and general driving styles. Besides the creative aspects in sound design, this tuning process is highly time-consuming. It must be ensured that load feedback, speed feedback and general interactivity with the synthetic sound meet the driver's expectations and match the intended emotional expressions of the sound concept. Testing the tuning parameters in real vehicles requires access to the vehicle prototype and all involved system components, which is often not granted in early development stages. A key approach to overcome this difficulty is the application of acoustic driving simulator technology, directly linked to the main tuning parameters. Combining this methodology with an efficient procedure for perceptive assessment of the sound design model, an interactive approach to active sound design is established. This paper discusses current progress in the field of efficient tuning of active sound design models, presenting a case study for a high-performance electric vehicle.

Analysis of Aluminum–Cerium Based Conductor Die-Casting Alloys for High Performance Electric Vehicle Powertrain Applications

Analysis of Aluminum–Cerium Based Conductor Die-Casting Alloys for High Performance Electric Vehicle Powertrain Applications

A novel instrumentation approach for achieving in-situ temperature sensing of a Li-ion cylindrical cell under immersion cooling

Battery thermal management systems are critical for high-performance electric vehicles, where the ability to remove heat and homogenize temperature distributions in single cells and packs are key considerations. Immersion cooling, which immerses the battery in a dielectric fluid, can improve cooling efficiency compared to air cooling. However, stringent instrumentation standards make in-situ monitoring under immersion cooling a difficult challenge. This study proposes a novel cell instrumentation method based on the integrated combination of three O-rings, which for the first time achieves in-situ temperature sensing of batteries under oil-immersed cooling conditions. Reliability of the sealing system and instrumentation methodology is ensured by leakage tests and oil corrosion assessment. Data such as cell impedance and discharge capacity also support the success and reliability of the instrumentation process without affecting the battery performance. Compared with natural air cooling, immersion cooling can reduce the temperature rise during battery operation by >10 °C under high C-rate discharge conditions. However, this is accompanied by an increase in radial temperature gradient. The temperature gradient of the cell with oil immersed reaches a maximum of >7 °C, while the temperature gradient under natural cooling under the same test conditions is only 3 to 4 °C. This leads to intensified temperature inhomogeneity of the cell, which may accelerate the local ageing and degradation. Our instrumentation approach contributes to a deeper understanding of the thermal behaviour of batteries under direct immersion cooling, aiding the development of more advanced cooling strategies and associated battery thermal management models.

Prelithiated Silicon Anodes for High-Energy and High-Power Lithium-Ion Batteries

Lithium-ion batteries (LIBs) are pivotal in powering modern electronic devices and next-generation land and air electric vehicles. Silicon-based anodes are considered the next technology to replace traditional graphite anodes due to their high theoretical capacity. However, the inherent challenges associated with their large volume expansion and high irreversible capacity loss (IRCL) limit their practical application. This abstract explores our patented strategy of prelithiation as a viable approach to mitigate the IRCL limitations of SiOx dominant anodes. Prelithiation involves the precise addition of supplemental lithium into the anode, mitigating the adverse effects of initial lithiation and enhancing overall cyclability, energy, power, and extreme fast charge capability for silicon oxide dominant LIBs. Various prelithiation techniques, including Li powder, Li slurry, Li-foil, and the chemical doping of SiOx are examined to evaluate their effectiveness in providing supplemental lithium. The effectiveness of the prelithiation process is assessed by examining the impact on the structural stability, cycling performance, power capability, and rate capability of SiOx dominant anodes integrated into high-capacity (~30 Ah) pouch cells. Our focus is to emphasize prelithiation as a practical and scalable solution to enhance the electrochemical performance of SiOx dominant anodes, contributing to the development of high-energy and high-power LIBs enabling advanced air mobility and high-performance electric vehicles. The findings presented in this abstract contribute to the growing body of knowledge aimed at advancing the fundamental understanding and practical implementation of prelithiation as an enabler for SiOx-based anodes in LIBs. Figure 1

Ionblox’s SiOx-Based, High-Energy, High-Power Li-Ion Battery for Performance Electric Vehicles and Electric Aviation

Demands on land-based, high-performance electric vehicles (EVs) and electric aviation, by means of electric conventional takeoff and landing aircraft (eCTOLs) and electric vertical takeoff and landing aircraft (eVTOLs) demand more on a secondary cell chemistry than ever before. There are many secondary cells on the market that offer energy density, power density, fast-charge capability, or cycle life, but few, if any other manufacturing-ready cells, offer a combination of all four. IONBLOX has solved this by pairing it’s patented, Pre-lithiated SiOx anode with a high nickel, NMC cathode to produce cells exceeding 330 wh/kg. Herein we describe the performance of our 32 Ah cell, featuring high-energy density, high-power density, extreme fast charge capability, and good cycle life, within a package that is already in production.In particular, challenges for the eVTOL market will be addressed, which require peak power demand on the cell at low state-of-charge, without reducing the energy density. Methods for characterizing cells for such high-power applications will be further explored. DCIR pulse characterization and more customized testing like usable energy testing, which is important for identifying the applicable energy density for high-power use cases, will be demonstrated. Additionally, extreme fast charge capability is described on our large format cells with 5 min charge to >60% total cell capacity, over 1000 cycles. This shows such a cell is up to the expectations of a consumer familiar with the timing of a standard gasoline pump. Contribution from the information presented herein demonstrates the state of Si-based anode chemistry and can serve as useful guidelines to the academic community as future technologies are pursued for similar applications Figure 1

A Smart and Efficient Cooling System Design for High-Performance Electric Vehicle Battery Packs

A Smart and Efficient Cooling System Design for High-Performance Electric Vehicle Battery Packs

Design and optimization of a high-performance multi-barrier IPMS motor for an electric scooter and bicycle.

Acknowledging the growing importance of electric vehicles (EVs) in the face of environmental concerns and increasing mobility needs, this study focuses on enhancing the performance of the electric motor, a critical component in EVs. The electric motor of these battery-powered vehicles is expected to have optimal characteristics and efficiency. This paper presents a comprehensive investigation into the design and optimization of a multi-barrier interior permanent magnet synchronous motor tailored for e-scooters and electric bicycles. A multi-barrier rotor structure is proposed and analysed through finite element method simulations to optimize key design parameters. The parametric analysis examines the influence of geometric variables on key motor performance criteria, including efficiency, cogging torque and weight. A correlation analysis of the variables was conducted. A very high positive correlation (0.999) was revealed, especially between the 'magnet duct dimension parameter' and efficiency. A very high negative correlation (-1) was found between 'distance from duct bottom to shaft surface' and efficiency. The optimized motor design achieves a theoretical improvement of around 7% in efficiency, reaching an overall efficiency of 89.86%. This study highlights the consideration of multiple factors such as efficiency, cogging torque and weight in the design process for the development of sustainable and high-performance EV motor designs.

Energy Management Strategy with Regenerative-Breaking Recovery of Mixed Storage Systems for Electric Vehicles

Abstract The present paper addresses the energy management (EM) strategy between batteries and ultracapacitors (UCs) in a dual-propulsion urban electric vehicle (EV). The use of two propulsion machines proves advantageous for high-performance EVs facing spatial constraints. Allocating load power requirements among the propulsion machines and energy storage components poses a significant challenge in this design. In this paper, the control strategy presents managing the energy flow between the converters and the two brushless DC motors (BLDCs) motors via the DC link in order to maintain the energy demand of the EV coming from the dynamics of the latter. For this, power control is carried out by a management algorithm. This management is based on the power requested/generated by the two machines (BLDCs), the state of charge of the batteries (SOCBat) and the state of charge of the ultracapacitors (SOCUC). The bidirectional DC-DC converter is controlled with current to ensure the functioning of the motor or the generator of the vehicle. We also integrate the controls of the DC bus and BLDC. Additionally, the recovered energy during braking is stored in the battery or in the UC depending on the operating conditions.

High-Performance Ni-Rich Li[Ni0.92−XCo0.04Mn0.04Alx]O2 Cathodes for High Energy Density Lithium-Ion Batteries

A high-performing Ni-rich Li[Ni1−x−y−zCoxMnyAlz]O2 (NCMA) is developed by comparing the electrochemical performance of Li[Ni0.92−xCo0.04Mn0.04Alx]O2 cathodes (x = 0, 0.01, 0.03, and 0.05). Excessive Al leads to the accumulation of Al on secondary particle surfaces and at grain boundaries, resulting in the refinement of the cathode microstructure. Increasing the Al content enhances the degree of refinement, including primary particle elongation and radial alignment. A well-refined microstructure effectively dissipates the strain caused by the rapid contraction of unit cells during the H2 phase → H3 phase transition near the charge end, thereby suppressing the formation of internal cracks. An Al content of 3 mol% provides optimal overall electrochemical performance. The full cell with an optimized Li[Ni0.894Co0.041Mn0.034Al0.031]O2 cathode exhibits excellent long-term cycling stability, retaining >90% of its initial capacity after 500 cycles and an energy density of 740 Wh Kg-1. In contrast, a Li[Ni0.91Co0.04Mn0.04Al0.01]O2 cathode, in which Li and Ni cation mixing is prevented, loses 38.3% of its initial capacity after 500 cycles. This research demonstrates that an NCMA cathode with the optimal Al content can surpass existing layered cathodes and represents a new class of Ni-rich layered cathodes suitable for high-performance electric vehicles.

Economic efficiency of high-performance electric vehicle operation based on neural network algorithm

The operation Economic efficiency of high-performance electric vehicles is relatively low. There are still certain limitations on the range of electric vehicles and the coverage of charging facilities, which affects the user experience and convenience. This paper aims to explore ways to improve the Economic efficiency of electric vehicle operation based on neural network algorithm. Based on the neural network algorithm, this paper establishes a prediction model for the operational Economic efficiency of high-performance electric vehicles. By analyzing and modeling the relevant data, we can predict the operational Economic efficiency of electric vehicles, and extract the influencing factors from it. In this paper, the operation Economic efficiency of high-performance electric vehicles is predicted and analyzed through neural network algorithm, and the methods to improve the operation Economic efficiency are proposed. These methods can provide certain reference and guidance for the development of the electric vehicle industry.

Optimal order quantities, buyback prices, and government subsidies for cars in a sharing economy environment

To reduce carbon emissions from urban transportation and increase the popularity of electric vehicles (EVs), many governments have provided purchase subsidies to incentivize customers to buy EVs. As the popularity of EVs increases, some governments have begun to provide battery recycling subsidies to car manufacturers. However, in a sharing economy environment, the mechanism under which the purchase subsidy and the battery recycling subsidy promote the popularity of EVs and the maturity of the EV sharing market is unclear. In this study, two commonly applied governmental subsidy policies are introduced: one considers only purchase subsidy (P-policy), and the other considers both purchase subsidy and recycling subsidy (P&R-policy). Under each policy, a stylized Stackelberg game model is constructed considering the forward and reverse supply chains in the car-sharing market. The objective of this study is to obtain the car-sharing platform’s optimal ordering quantities of EVs and fueled vehicles (FVs), the car manufacturer’s optimal buyback prices of used EVs and FVs, and the government’s optimal subsidies under the P-policy and P&R-policy. Through model-solving and analyses, it is found that both policies could increase the popularity of EVs in the car-sharing market, and the P&R-policy has a higher promotion effect on EVs than the P-policy. As for policy implementation, this study suggests that with the popularity of EVs, the subsidies under each policy should be decreased. Particularly, the declining rate of the purchase subsidy for high-performance EVs should be lower than that for low-performance EVs. The recycling subsidy for low-performance EVs should be reduced the most.

A Proposal for a Simplified Systematic Procedure for the Selection of Electric Motors for Land Vehicles with an Emphasis on Fuel Economy

The selection of the electric motor for the propulsion system in electric vehicles is a crucial step, as it determines the final performance of the vehicle. The design of the propulsion system of an electric vehicle, although similar in principle to that of a conventional endothermic engine, requires a change in vision. Indeed, the main problem in an electric vehicle is its range, which depends not only on the weight of the vehicle but also on the type of powertrain, type of transmission and engine, several factors that are difficult to assess at an early stage. In some cases, during the preliminary design phase of the propulsion system, one simply estimates the maximum power required by the vehicle, neglecting the calculation of the range. This evaluation is postponed to later stages, causing increased complexity and interaction during the propulsion system evaluation process. In this study, vehicle autonomy is taken into account from the outset with the aim to reduce this iteration. This paper proposes a preliminary electric motor selection method for land vehicles, highlighting the importance of smoothing the sampled data of driving cycles. A method for obtaining approximate efficiency maps of the electric motor is also illustrated, and it is shown how the total gear ratio affects vehicle energy consumption. Ultimately, this work makes a contribution to the design of more efficient and high-performance electric vehicles. This topic is more oriented to helping automotive manufactures choose in a fast and structured way electric motors for their vehicles.

A Systematic survey on Estimation of Electrical Vehicle

Due to the gasoline crisis, electric vehicles are growing in popularity. The usage of electric and battery-powered automobiles is being encouraged worldwide. This campaign also heavily relies on the usage of renewable energy sources to provide electricity. In order to build electric vehicles, engineers use static and dynamic equations. Around the world, competitions are being held to design high-performance electric vehicles. The automotive industry and businesses are transitioning a portion of their fleet from gasoline-powered vehicles to batteryoperated electric vehicles. Most vehicles today offer good performance at slightly increased costs to the consumer. The battery technology is improving andhence enhancing the range of vehicles. The movement of use of electrical vehicle will strengthen as more people are getting involved in the design and use of electric vehicle.

Analytical Routes to Chaos and Controlling Chaos in Brushless DC Motors

This study examines the dynamics in a brushless DC motor (BLDCM) and methods used to control potentially chaotic behavior or behavior similar to chaotic processes in these systems. Bifurcation diagrams revealed complex nonlinear behaviors over a range of parameter values. In the resulting bifurcation diagram, period-doubling bifurcation, period-three bifurcation, and chaotic behavior can clearly be seen. We used Lyapunov exponents and Lyapunov dimensions to show the occurrence of chaos in a BLDCM. We then used the state feedback method to control chaos behaviors in the same BLDCM. Numerical simulations show the feasibility of the suggested means. Analysis of robustness against parametric perturbation in a BLDCM was performed from the perspective of Lyapunov stability theory and by using numerical simulations. We believe that studying the nonlinear dynamics and controlling chaos in BLDCMs will help to advance the development of high-performance electric vehicles.

Periodically aligned channels in Li[Ni0.5Co0.2Mn0.3]O2 cathodes designed by laser ablation for high power Li ion batteries

Lithium-ion batteries are widely used in electric vehicles (EVs) owing to their high energy density and cycling stability. However, achieving high driving mileage per charging time under high electrode mass loading remains a significant challenge for high performance EVs. Herein, a new strategy to improve the rate capability of thick electrodes is proposed based on the laser ablation, which generates periodically aligned channels in the electrodes. To investigate the effect of porosity and interfacial area on the power performance, Li[Ni0.5Co0.2Mn0.3]O2 cathode-based laser-processed electrodes (LPEs) are fabricated by adjusting the spacing and depth of channels. Comparing the relative capacity of C16C/C0.25C, LPEs shows improved value of 19.83%, whereas the conventional electrodes (CEs) of 0.08%. Furthermore, the rate capability of LPEs is superior to that of CEs under the same mass loading, arising from the formation of the channels rather than the mass loss evolved during the laser ablation. The exceptional rate capability of LPEs is attributed to the alleviated activation/concentration polarization, enhanced Li-ion diffusion kinetics, and reduced tortuosity. The laser ablation is an effective strategy, as it can be compatible with any cathode and anode materials.

Single-Crystalline Ni-Rich layered cathodes with Super-Stable cycling

Robust single-crystalline Ni-rich cathodes with increasing Ni proportion, LiNi 0.83 Co 0.11 Mn 0.06 O 2 (SC83), LiNi 0.88 Co 0.06 Mn 0.06 O 2 (SC88), and LiNi 0.95 Co 0.03 Mn 0.02 O 2 (SC95) were successfully designed with molten salt-assisted method, and the correlation between the Li + storage properties, particle microcracking, surface phase transitions, and Ni fraction in the single-crystalline Ni-rich cathodes have been profoundly investigated. • -crystalline Ni-rich cathodes with increasing Ni proportion were designed with molten salt-assisted method. • The single-crystalline LiNi 0.83 Co 0.11 Mn 0.06 O 2 cathode presents superior structural stability and cycling durability. • Performance degradations were attributed to the aggravated Li/Ni mixing and H2 ↔ H3 phase transition. • It provides approach for designing high-energy density and stable single-crystalline Ni-rich cathodes. Further commercial development of polycrystalline Ni-rich layered cathode is severely hindered by the deep-rooted particle microcracking, mainly initiated among the randomly orientated grain boundaries of the primary particles. Herein, robust single-crystalline Ni-rich LiNi 0.83 Co 0.11 Mn 0.06 O 2 (SC83) prepared by molten salt-assisted method shows the enhanced structure stability and cycling durability. It’s found that the particle microcracking is effectively removed for SC83 cathode during prolonged cycling helped with its eliminated grain boundaries and slight crystal shrinkage, leading to superior capacity retention of 92.8% after 100 cycles. Notably, the discharge capacity and energy density are effectively boosted with increasing Ni fraction majorly based on the more available Ni 2+ /Ni 3+ redox, giving rise to high capacities of 211.2 and 219.4 mAh g −1 for LiNi 0.88 Co 0.06 Mn 0.06 O 2 (SC88) and LiNi 0.95 Co 0.03 Mn 0.02 O 2 (SC95) cathodes, respectively. However, the particle microcracking is progressively exacerbated owing to the aggravated Li/Ni mixing and H2 ↔ H3 phase transition with Ni proportion higher than or equal to 88% in SC cathodes, resulting in severe structure collapse and capacity fading during high-rate cycling, in which a poor capacity retention of 51.8% after 250 cycles at 5C is observed for single-crystalline SC95cathode. This work sheds light on the rational design of single-crystalline Ni-rich cathodes, and highlighted the trade-off between the energy density and cycling durability, facilitating the extensive applications of single-crystalline Ni-rich cathodes in high-performance electric vehicles (EVs).

Implementation of additive manufacturing technologies in the design and build process of a two-seater high-performance electric vehicle

This paper seeks to document the implementation of additive manufacturing (AM) technologies in the Electric Vehicle (EV) design cycle. AM has been known to shorten prototyping phases and provide an edge in small volume or customised product manufacturing in most product design. It also opens more possibilities for generative design methods in computer aided design (CAD) for better weight saving optimisations and organic form aesthetics. In more mature engineering fields, such as automotive engineering, we start to see companies implementing AM technologies not just to their prototypes, but also to final parts and components of their products. Insights on how effective 3D printing technology can assist the automotive industry in simplifying their processes, speed up design timeline, as well as any improvements on their design aesthetics and performances will be covered in this paper.

Design of ultrafine silicon structure for lithium battery and research progress of silicon-carbon composite negative electrode materials

As demand for high-performance electric vehicles, portable electronic equipment, and energy storage devices increases rapidly, the development of lithium-ion batteries with higher specific capacity and rate performance has become more and more urgent. As the main body of lithium storage, negative electrode materials have become the key to improving the performance of lithium batteries. The high specific capacity and low lithium insertion potential of silicon materials make them the best choice to replace traditional graphite negative electrodes. Pure silicon negative electrodes have huge volume expansion effects and SEI membranes (solid electrolyte interface) are easily damaged. Therefore, researchers have improved the performance of negative electrode materials through silicon-carbon composites. This article introduces the current design ideas of ultra-fine silicon structure for lithium batteries and the method of compounding with carbon materials, and reviews the research progress of the performance of silicon-carbon composite negative electrode materials. Ultra-fine silicon materials include disorderly dispersed ultra-fine silicon particles such as porous structures, hollow structures, and core-shell structures; and ordered ultra-fine silicon, such as silicon nanowire arrays, silicon nanotube arrays, and interconnected silicon nano-films. The article analyzes and compares the composite method of ultrafine silicon and carbon materials with different structural designs, and the effect of composite negative electrode materials on the specific capacity and cycle performance of the battery. Finally, the research direction of silicon-carbon composite negative electrode materials is prospected.

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Modelling of Brushless DC Motor Drive for Electric Vehicle Application

In Electric vehicle, motor plays a significant role. In wheel, motor improves the efficiency and safety of high-performance Electric vehicle. There are a lot of motors available in market, out of all considering their advantages and disadvantages Brushless DC motor is chosen as an efficient motor for Electric vehicle propulsion. The reason behind to choose BLDC motor is because of its desired torque vs speed characteristics, cost of maintenance is low, efficiency is high and has high power density. In this model simulation of an accurate and precise BLDC drive for Electric vehicle application is done and Simulation results such as speed, Electromechanical torque, and various phase voltages graphs are obtained.