Session: 12-04-01: Multiscale Models and Experimental Techniques for Composite Materials and Structures

Paper Number: 91702

91702 - Investigation of Crashworthiness of Electric Vehicle’s Battery Enclosure Made by Carbon Fiber Organosheets Using Finite Element Analysis 

In this research, a finite element analysis was used to analyze the strength of carbon fiber organosheets in the structural design of an electric vehicle’s battery enclosure. Demand for electric vehicles is increasing exponentially. One of the main limitations of current electric vehicles performance compared to traditional IC engine vehicles is its limited range. The use of carbon fiber organosheets for different parts of the vehicle reduces the overall weight of the vehicle resulting in increased range. This work focuses on the use of carbon fiber organosheets for manufacturing electric vehicles battery enclosure which is one of the large components currently made using Aluminum alloys.

Coupled simulations were performed for the thermoforming process of the enclosure panel and side pole impact test. Using a thermoforming simulation, carbon fiber layers are formed to the surface of a die representing the geometry of the desired battery enclosure. Carbon fiber orientation was considered during these simulations along with interactions of different organosheets with each other and with die/punch. Effect of temperature was also considered with organosheets pre-heated to 300 degrees, punch and die heated to 200 degrees and the whole assembly was considered to be in the room with an ambient temperature of 24 degrees. The viscosity of epoxy was also modeled, and it was varied with respect to temperature. Multiple simulations were performed with the different numbers of organosheets resulting in different part thicknesses from 1 mm to 4 mm. These simulations can help engineers to modify the design of the battery enclosure part so that defects such as thinning, wrinkling, jamming can be avoided. A sufficient relief angle was also provided for the safe and easy removal of the punch after the process is completed.

A side pole impact test was then simulated to test the crashworthiness of the battery enclosure for various impact speeds (25 miles/hour to 55 miles/hour). Side pole impact test is one of the standard safety tests all vehicles must undergo before mass production. Eclectic vehicle’s battery enclosure was found to be most vulnerable in this test due to its location. Hence this test was selected for our study. Fiber orientations obtained from thermoforming simulations were used in crash simulations by performing a draping operation. A non-structural mass was added to mimic the mass of the battery module inside the battery enclosure to increase the inertia. The behavior of enclosure obtained by the crash test was compared with the behavior of enclosure with the same geometry made from traditional Aluminum alloys and the crashworthiness of both materials was found to be similar for a wide range of impact speeds. A significant weight reduction was observed without a decrease in crashworthiness of the enclosure.

Presenting Author: Shank Kulkarni Pacific Northwest National Laboratory

Presenting Author Biography: Working at Pacific Northwest National Laboratory as Computational Scientist.

Authors:

Shank Kulkarni Pacific Northwest National Laboratory
Mohammod Taufique Pacific Northwest National Laboratory
Forrest Hale Pacific Northwest National Laboratory
Arnaud Dereims ESI NA
Ramesh Dwarampudi ESI NA
Ram Devanathan Pacific Northwest National Laboratory