This paper presents a fast and effective approach to Li-ion battery performance modeling, particularly suited for automotive applications (i.e. HEV, PHEV, BEV). A second-order electrical equivalent circuit model made up by one voltage source, one series resistor and two series RC blocks (dual-polarization model), is here selected as the best trade-off solution for the task, addressing both acceptable levels of accuracy and complexity. While a lithium-iron-phosphate cylindrical battery cell is chosen for the purpose of the study, the presented procedure has broader validity and is mostly independent of Li-ion chemistry and/or cell format. The battery model is parametrized through a low timeconsuming current pulse test, performed during both charging and discharging, at different state of charge levels. The temperature and load-current effects on the battery performance are not considered for simplicity and lightness of the presented model. Validation is carried out by comparing measured and simulated results during the dynamic current pulse test, showing a high level of agreement between the two.

This paper describes the design procedure to enhance the damping properties of a multimaterial lightweight suspension arm for a C-segment vehicle. An innovative viscoelastic material has been used to join carbon fiber with steel that has a function of passive constrained layer damper and adhesive simultaneously. Therefore, the hybrid technology applied has been focused on reducing the LCA mass, diminishing the steel thickness, and adding a CFRP tailored cover without compromising the global mechanical performance. Particular attention has been paid to the investigation of the dynamic response in terms of vibration reduction, especially in the range of structure-borne frequencies of 0–600 Hz. Two different viscoelastic materials have been evaluated in such a way to compare their stiffness, damping, and dynamic properties. The experimental test results have been virtually correlated with a commercial FEM code to create the respective material card and predict the real behavior of the LCAs (original and hybrid). The experimental modal analysis has been performed and compared on both the arms highlighting a very good correlation between virtual and experimental results. In particular, the hybrid LCA allows an interesting improvement of damping ratio, about 3,5 times higher for each eigenmode than in the original solution.

This paper is focused on the design, analysis and testing of a multi-material (carbon fibre and steel) Lower Control Arm (LCA) of a McPherson suspension for a C segment vehicle. Therefore, starting from the existing component (made of steel), the LCA mass has been reduced by using a hybrid technology, diminishing the steel thickness and adding a carbon fiber tailored cover without compromising the mechanical performance in terms of stiffness and stress distribution. In so doing, it has been possible to evaluate the potential and the capabilities of the hybridization without re-designing the component totally. In particular, it has been developed a specific methodology that combines both virtual and experimental procedures to face the hybridization challenges of mechanical coupling, safety and lightweight. For these reasons, the multi-material lower control arm represents a noticeable case study in which this methodology has been applied, correlated and validated.

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Weight reduction and high mechanics performance are one of the challenges of the automotive industries future. A particular and interesting field is the application of carbon fibres in combination with structural foams. These allow to realize creative shapes for the car body but also strength and tough elements for the chassis, according to the necessity to combine style with design and engineering aspects. Nowadays, the problem of carbon fibre technology is the cost of production and the recyclability, so the major applications are in the racing field. One interesting application is the body of the prototype called IDRA, a low consumption vehicle which participated in the European Shell Eco-marathon. The chassis is a structural frame made with structural foam, the body is a part of the chassis and it is made of carbon fibre. The result is a well made car body integrated with all the sub-systems: steering, brakes, wheels, cockpit, electric wiring, controls, fuel cell, electric motor and transmission. The different design and production steps, from the concept phase and structural analysis made by means of finite element techniques to the production and the assembling of the monocoque, are discussed.

Abstract. In this paper, a lightweight suspension system for small urban personal transportation vehicle is presented. A CFRP (Carbon fiber reinforce polymer) beam spring has been used to efficiently integrate the functions of suspension control arm and anti-roll bar. Composites materials were chosen to tailor the required behavior of the beam spring and to reduce the weight. Furthermore, larger space for engine compartment has been provided thanks to the compact arrangement of beam suspension components. This suspension could be installed on electric/hybrid vehicles and conventional automobiles.

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This paper presents a set of time-domain electrical equivalent circuit models for battery voltage prediction under arbitrary current profiles. The circuit model is composed by passive electrical components like resistance, inductance and capacitance. The constant phase elements are introduced in the model, which are usually used in electrochemical impedance spectroscopy analysis to describe the electrical property of double layer capacitors between electrode and electrolyte. The aim of the paper is the modeling in the time-domain of the constant phase elements. Two models are proposed. Model's accuracy and run speed are evaluated by comparing experimental results obtained by an appropriate testbed and simulation results obtained by the implementation and the execution of the model using Matlab software.