Total Thermal Management of Battery Electric Vehicles (BEVs)

2018-37-0026

05/30/2018

Features
Event
CO2 Reduction for Transportation Systems Conference
Authors Abstract
Content
The key hurdles to achieving wide consumer acceptance of battery electric vehicles (BEVs) are weather-dependent drive range, higher cost, and limited battery life. These translate into a strong need to reduce a significant energy drain and resulting drive range loss due to auxiliary electrical loads the predominant of which is the cabin thermal management load. Studies have shown that thermal sub-system loads can reduce the drive range by as much as 45% under ambient temperatures below −10 °C. Often, cabin heating relies purely on positive temperature coefficient (PTC) resistive heating, contributing to a significant range loss. Reducing this range loss may improve consumer acceptance of BEVs. The authors present a unified thermal management system (UTEMPRA) that satisfies diverse thermal and design needs of the auxiliary loads in BEVs. Demonstrated on a 2015 Fiat 500e BEV, this system integrates a semi-hermetic refrigeration loop with a coolant network and serves three functions: (1) heating and/or cooling vehicle traction components (battery, power electronics, and motor) (2) heating and cooling of the cabin, and (3) waste energy harvesting and re-use. The modes of operation allow a heat pump and air conditioning system to function without reversing the refrigeration cycle to improve thermal efficiency. The refrigeration loop consists of an electric compressor, a thermal expansion valve, a coolant-cooled condenser, and a chiller, the latter two exchanging heat with hot and cold coolant streams that may be directed to various components of the thermal system. The coolant-based heat distribution is adaptable and saves significant amounts of refrigerant per vehicle. Also, a coolant-based system reduces refrigerant emissions by requiring fewer refrigerant pipe joints. The authors present bench-level test data and simulation analysis and describe a preliminary control scheme for this system.
Meta TagsDetails
DOI
https://doi.org/10.4271/2018-37-0026
Pages
7
Citation
Chowdhury, S., Leitzel, L., Zima, M., Santacesaria, M. et al., "Total Thermal Management of Battery Electric Vehicles (BEVs)," SAE Technical Paper 2018-37-0026, 2018, https://doi.org/10.4271/2018-37-0026.
Additional Details
Publisher
Published
May 30, 2018
Product Code
2018-37-0026
Content Type
Technical Paper
Language
English