SAE J3125_202211

This SAE Information Report is specific to integration of rechargeable energy storage systems (RESS) into electrification of buses of all types which comprehends safety, performance, life, etc., utilizing worldwide standards and regulations as references in order to maximize existing work. This document applies to both purpose-built electric buses and retrofit electrified buses at an original equipment manufacturer (OEM). This document does not comprehend retrofitting of buses outside the OEM manufacturing environment. The global electrified bus market is growing rapidly to meet the demands of abating environmental impact of fossil fuel-based propulsion systems. This rapid electrification is happening at an accelerated rate with many manufacturers taking design technology to limits, or not understanding the full scope of proper engineering protocols in designing these sophisticated electrified systems. Both of these scenarios may create safety, performance, life, and cost concerns to the manufacturer and to large civic exposure (the passengers of these machines). It is the intent of this SAE Information Report to create a comprehensive information report which provides guidance in areas which are known to create safer performing machines with life expectancies and cost value which provides maximum benefit to the general public. This document will draw information from worldwide standards to provide guidance in design of electrified bus products. It is not the intent of this document to comprehend the entire bus design, but to provide guidance to those design aspects impacted by rechargeable energy storage system (RESS) integration. This SAE Information Report will provide a compilation of design philosophies in current practices for the bus electrification industry. This will provide industry professionals guidance in key aspects of bus electrification that are important and where to seek further information. This SAE Information Report is a precursor to an SAE Recommended Practice, which will follow within 18 months of this document’s publication date. It is intended to become a historic document for the preservation of design philosophy with current state of the art in electrified bus design. This document creates the consensus knowledge base of participating members who represent the bus industry, battery industry, and ancillary components used in the electrification of buses.