Proposal: PhD
Title: The development of a thermal management system to pre-heat electric vehicle batteries for
use in extreme cold temperatures
Background and area of work
Performance of a hybrid electric vehicle (HEV) depends strongly on the performance of its highvoltage battery pack, which can be influenced by extreme temperature. In extreme cold
temperatures such as those found in Northern Europe, Scandinavia, Russia and North America a
battery pack performance is reduced as temperatures often reach minus 20 and below. Batteries
may suffer from slow start, reduced range and possible slow rate of charge. A solution is to pre-heat
the internal core, a module or an individual cell with electric heaters or a hot fluid. However, in order
to pre-heat and regulate possible thermal instabilities it is necessary to simulate winter conditions to
analyse and validate range of technological choices that guarantee consistent vehicle performance
and safety in cold conditions.
Is it necessary to examine how cold weather conditions affect the battery, notably in terms of:
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•
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Reduced Capacity: a cold battery will not fully charge and therefore range is reduced
Reduced Power: a cold battery cannot provide all the power required by the motor.
Therefore acceleration is reduced
Reduced Charge: a cold battery cannot be charged at the normal ‘fast’ charging station at
the usual charging time. This is affected by ‘street charging only’
To address the above issues a thermal management system needs to be designed, developed and
tested in extreme cold weather situations to:
•
•
Characterise the effect of temperature on battery performance, based upon the above
characteristics
Evaluate a novel method of controlling the temperature of the batteries that will not
introduce a parasitic load into the system and pre-heat the batteries to ensure capacity,
power, charge and safety are not compromised
Research problem and objectives of the research
The research would build upon the limited amount of research available to develop a new system
which could determine the current required to pre-heat the batteries to a desired temperature. In
order to achieve this it will be necessary to design/adapt a suitable heat exchanger to direct heat to
the batteries compartment held inside the environmental chamber. Each battery pack will be tested
at several temperatures and “driven” over a standard drive cycle. Telematics data will be collected
on battery condition as well as the demand imposed upon the pack by the drive cycle.
Using a specially developed environmental chamber to house the battery pack it is proposed to
reduce the ambient temperature around the pack to minus 35o C whilst introducing a heated
medium into the battery compartment either in the form of a gas or a fluid in order to manage the
battery temperature. The battery pack will then be connected to the EV Development Dynamometer
based at AMAP, University of Sunderland and subjected to loads via approved drive cycles. Using
telematics the performance of the batteries will be evaluated to determine how much heat will be
necessary to manage the performance of the batteries. Heat will be supplied by an innovative
system.
Applicable techniques
A system of thermal couplings or thermal detectors could be used to monitor the internal and
external heat range of the battery pack, this system would need to be connected to the in-car
system to determine the state of health of the batteries. A software system would need to be used
to monitor the battery, analyse the data and transmit the required information to the occupant via a
wireless system.
Outline Methodology
• Conduct research into current techniques used to monitor battery thermal management
systems
• Using a range of sensors, develop a system to monitor the required capacity (power, charge
and capacity) to ensure normal start conditions in cold weather
• Develop a new system to pre-heat the EV battery pack, based upon the above points
• Develop a software system to collect, store and analyse the data which must be connect to
the EV existing system
Skills and knowledge required by interested applicant
Essential
Engineering degree (preferably electrical). A certain amount of mechanical design
will also be required to design the ancillaries for the test rig.
Desirable
Knowledge of software development
Knowledge of sensor technology and applications
Knowledge of electric vehicle electrical systems
Knowledge of design issue
Contact details
Sponsor: Dr David Baglee
Project Manager and Senior Lecturer
Department of Computing, Engineering and Technology
Institute for Automotive and Manufacturing Advanced Practice
T: +44 (0)191 515 2869
E: david.baglee@sunderland.ac.uk
Research Student Applications
T: +44 (0)191 515 3546
E: cat-research-admin@sunderland.ac.uk