Design and modification of electric vehicle chassis frame for swapping mechanism of battery packs

Abstract

Automotive industries are moving towards the manufacturing of electric vehicles to reduce the consumption of fossil fuel and related harmful exhaust emissions from engines. In electric vehicle energy stored in the battery is the source of the energy to drive the electric vehicles. At the moment the size and the weight of the battery pack required for given mileage is very much high when compared to its counterpart IC engine. Size and shape of battery varies depending on the type of the battery selected and vehicle model. The electric vehicles impose additional requirements on chassis of the vehicle which is the load bearing frame of the vehicle. The chassis should be able to bear the heaviness of the battery pack and sustain load variation when swapping the battery. Provision of swapping electric vehicle battery helps in minimizing the wastage of vehicle time in waiting for charging the battery. The objective of this thesis work is to modify of the existing RAV4 EV 2014 electric vehicle chassis frame to swapping purpose rather than permanent battery pack on chassis frame. Material AISI 1020 and rectangular cross section in 80 mm x 40 mm x 4mm is selected to the electric vehicle chassis frame. The modeling was done by using CATIA V5 R20 the total deformation of chassis frame is 1.007 mm, equivalent stress is 115.88 MPa and the life of the chassis on full load is 130 days without deformation. In modal analysis and harmonic analysis there is no chance of resonance frequency existence in 10 modes of analysis after having this the weight of the electric vehicle battery pack is decreased from 383.51kg to 345.615Kg by shape minimization of the cooling plate and the BTMS fluid (water) inlet temperature is 20oC, outlet temperature of fluid is 38oC was done by transient analysis method on EXCEL. Finally prototype of a model of miniature size has prepared for exhibiting the shape of modified chassis.