DESIGN AND OPTIMIZATION OF LIGHTWEIGHT LITHIUMION BATTERY PROTECTOR WITH 3D AUXETIC META STRUCTURES

• Main Author: Alfred Stephenson Biharta, Michael
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/54865
• Institution: Institut Teknologi Bandung

This research study involves the design and optimization of sandwich structure based on auxetic structure to protect the battery system for electric vehicle (EV) undergoing ground impact load. In this study, a pouch battery system is used due to great potential to be the next Li-Ion battery for EV due to its simplicity, higher energy density, and higher space efficiency compared to cylindrical or prismatic battery cells. However, just like the other form of Li-Ion battery, the pouch battery cells have a high fire risk due to the battery deformation. The sandwich structure is designed to prevent battery deformation due to ground impact. The core of the sandwich structure is filled with auxetic structure that has gone through optimization to maximize specific energy absorbed (SEA). Its performance is analyzed with non-linear finite element method. Five geometrical variables of the auxetic structures were analyzed using Analysis of Variance and optimized using Taguchi’s method. The optimum control variables are double-U hierarchal (DUH), the cross-section’s thickness = 2 ????????, the length of the cell = 10 ????????, the width of the cell = 17 ????????, and the bending’s height = 3 ????????. The optimized geometries are then arranged into three different sandwich structure configurations. The optimized sandwich structure has optimized DUH cell as the core that has been enlarged to 200% in length (single cell’s dimension 38 × 38 × 24 ????????), arranged in 11 × 11 × 1 cells resulting in total dimension and mass of 189 × 189 × 12 ???????? and 0.75 ????g. The optimized sandwich structure shows that the pouch battery cells are able to be protected very well from ground impact load with the maximum deformation of 1.92 ????????, which is below the deformation threshold for battery failure.