TEST & ANALYSIS
www.electrichybridvehicletechnology.com // July 2019 // 133
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this is the case, if it can be cured and what can
be done so that other cells do not succumb to
the same demise. Moreover, they want to
understand how new batteries can be designed,
optimized and operated diff erently to prevent
similar symptoms occurring,” says Brett.
An initial consultation will ensue, where as
much information as possible about the
battery’s history is ascertained and its past
testing records referred to. A perceived
symptom may point to a failure or abnormality,
but to move beyond the initial prognosis, the
EIL team will look for a group of symptoms,
which collectively identify a syndrome, from
which an accurate diagnosis can take place.
“Just as a medical doctor uses a stethoscope,
the EIL researchers use advanced
electrochemical tests to observe the battery.
Similarly, as an X-ray or ultrasound
examination is able to look inside a patient,
our scientists use X-ray computed tomography
and acoustic techniques to reveal the device’s
internal structure or material. A mass
spectrometry sample of the electrolyte is akin
to a blood test; a thermal imaging camera the
clinical thermometer; Raman laser
spectroscopy a retinal scan; or atomic force
micrograph a skin biopsy,” describes Brett.
The EIL’s approach is to identify the cause
of the problem and antagonize that mode of
stress or failure. For example, a battery
suspected of suff ering from temperatureaccelerated
degradation will undergo a series
of environmental chamber tests.
“To conduct the diagnostic
process eff ectively, the right tests
need to be done in the correct order
and over-testing needs to be avoided.
This triage process is guided by
process fl ow and fault-tree analysis
and the number of measurements
required minimized through
design-of-experiments,” Brett adds.
Sharing resources
While the EIL is one of the bestequipped
laboratories in the world
CHANGE OF SCALE
UCL is making a strategic investment
in research and training for the
electrification of transport through the
Advanced Propulsion Lab (APL), located
on the Queen Elizabeth Olympic Park in
Stratford and part of London’s US$1.3bn
(£1.1bn) East Bank project unveiled by
the Mayor of London last year. The
APL will be a world-leading, industryfacing
facility that will specialize in
battery and fuel cell R&D at technology
readiness levels from three and up,
and at scales of up to 1 MW. Dr Jay
Millichamp, who is designing the
facility, says that “facilities such as
dynos, environmental test chambers,
battery, fuel cell and electric motor
development suites will allow the
diagnostic metrology approach to be
extended to the entire powertrain.”
“Just as a medical doctor uses a
stethoscope, the EIL researchers
use advanced electrochemical tests”
Professor Dan Brett, co-director of the Electrochemical Innovation Lab
4. Post-mortem
examiniations of battery
modules at the
Electrochemical
Innovation Lab involve
extensive teardowns
5. The Advanced
Propulsion Laboratory
has access to testbed
vehicles for experiments
for electrochemical diagnostics, there will
inevitably be times where large facility
equipment is called for, or a second opinion
sought. The STFC Global Challenge Network
in Batteries and Electrochemical Energy
Devices, which is led by the EIL, provides
collaborative working with world-leading
scientists and access to synchrotron, neutron
and high-performance computing facilities,
such as those at the STFC Harwell Campus,
which has over US$2.5bn (£2bn) of research
infrastructure including the Diamond
Lightsource and the Isis Neutron and Muon
source.
“One of the most powerful ways in which to
gain a unique insight into operation, and
therefore accurate diagnosis, is the use of
correlative metrology,” says Dr Alex Rettie,
lecturer in advanced propulsion in the APL.
“The combination, often in real-time, of
multiple t 5 echniques enable the myriad
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