Battery Box is the housing unit for the Batteries in an automobile. The primary functions are to hold batteries in position and to assist periodic battery servicing. This unit contributes to vehicle curb weight considerably; it weighs in the range of 80-100 Kg for heavy duty commercial vehicles. Typically, battery box is rarely designed with regards to weight, cost and inherent fool-proofing measures during serviceability.This study provides a methodology adopted to design the Battery Box and its fixation with respect to Vehicle Dynamics and loading conditions. Brief discussions emphasizing design Root Cause Analysis for Field Failure in the Battery Box, selection and optimization of counter measures are enunciated in this paper. In this paper also provided the scope of improvement in existing design without increasing the total cost (Part Manufacturing and Assembly cost), this Optimal design outcome of Battery Box and Fixation assembly conformed to the standardized durability.