An Electrothermal Model of an NMC Lithium-Ion Prismatic Battery Cell for Temperature Distribution Assessment

Charge time has become one of the primary issues restricting the development of electric vehicles. To counter this problem, an adapted thermal management system needs to be designed in order to reduce the internal thermal gradient, by predicting the surface and internal temperature responses of the battery. In this work, a pseudo 3D model is developed to simulate battery cell performance and its internal states under various operational scenarios such as temperature and convection conditions as well as the applied current during charge and discharge. An original mesh of the JR is proposed where heat exchanges in the three directions (radial, orthoradial and axial) are considered. The model represents one of the solutions that enable increasing the lifespan of batteries while decreasing charging time. It offers the opportunity to optimize operating parameters to extend battery life. In this paper, attention was paid not only to the core and non-core components, but also to the experiments required to parametrize the thermal and electrochemical models (heat generation). Unlike existing approaches documented in the literature, the model developed in this work achieves an impressive balance between computational efficiency and result accuracy, making it a groundbreaking contribution in the field of electric vehicle technology

Evaluation of Dual Side Cooling System for Prismatic Batteries for Vehicle Aplications

Today lithium-ion stands out among the various battery technologies in vehicle applications thanks to their good energy density, low self-discharge and the absence of the memory effect. Nevertheless, lithium-ion batteries pose many challenges such as driving range, lifespan, safety issues and also the charging time which is still significant. In order to reduce the charging time, it is necessary to inject a very high current into the battery which may drastically raise its temperature and thus reduce its lifespan. Today, in most cases, the battery pack of an electric vehicle is cooled through flat cooling plates, mounted either by the lateral or the bottom surfaces. These cooling plates can also be used to warm up the battery in cold weather. But during the fast charge, this configuration poses some problems and can be not efficient enough to cool or heat the batteries. In this study, a battery module is thermally managed not only by the bottom cooling plate but also by a second cooling plate placed on the busbars. According to simulations and experimental tests regarding one case study, this configuration makes it possible to not only cool the module more quickly by reducing the thermal time constant by 47% but also reduces the battery maximum pick temperature reached with a conventional cooling system by 6°C. It stands out that the top cooling plate acts like a thermal bridge which unifies the temperature inside the battery module and thus support the equal ageing process of the batteries