The document provides a non-academic perspective on applied battery research from a senior engineer. It discusses the differences between typical academic research and real-world battery development for electric vehicles. Key differences include scale of materials used, metrics prioritized like energy density versus cycle life, and the gap between theoretical lab experiments and practical battery performance in a vehicle. The document urges avoiding excessive extrapolation from limited lab studies and emphasizes the value of transparency, reproducibility, and collaboration between academia and industry to bridge this gap.

1. A non-academic perspective on
applied battery research
Matthew J. Lacey

2. This presentation is
heavily based on our
recent perspective
article in Nat. Commun.:
doi:10.1038/s41467-023-35933-2
James Frith and Ulderico Ulissi are
acknowledged for contributing material to
this presentation
Opinions expressed in this presentation
are personal and do not necessarily
represent the view of my employer
(or, indeed, anyone else)
A non-academic perspective on applied battery research - M. J. Lacey 2

3. About me
2004-08 MChem, University of Southampton, UK
First battery research project: synthesis of LiFe1-xCoxPO4 as positive electrode
2008-12 PhD, University of Southampton, UK
3D microbatteries, electrochemistry, polymer electrolytes
2012 Postdoc, University of Southampton, UK
Redox mediators for Li-O2 batteries
2012-19 Researcher, Uppsala University, Sweden
Li-S batteries, electrochemical methods
2019-present Senior Engineer, Scania CV AB, Sweden
Team leader for Battery Cell, Materials Technology
A non-academic perspective on applied battery research - M. J. Lacey 3

4. From lab to gigafactory… to vehicle SOP
A non-academic perspective on applied battery research - M. J. Lacey 4
Most academic
research
OEMs
(typically)
Different scales, different goals, different priorities…
“Valley of death”

5. Li-based batteries, TRL5 and up
A non-academic perspective on applied battery research - M. J. Lacey 5
Key Performance Indicators (KPIs), e.g., for EV
• Range (gravimetric and volumetric energy)
• Power capability (charge/discharge, pulse, IR)
• Efficiency (energy, coulombic)
• Lifetime (and available State-of-Charge)
• Cost per energy ($/kWh)
• Operating temperature and pressure
• Safety at the system level
• Overall system cost, including EOL
• CO2e emission to produce a pack (CO2e/kWh)
• with carbon taxes, CO2e = $
Lithium-ion cells are complex devices, and each
component will generally influence each KPI
• Other considerations (incl. socio-economic)
• Manufacturing, scalability
• Supply chain, geopolitical issues
• Capital investments required, “ESG” risks
• Thermodynamic versus technological limit

6. What does the state-of-the-art look like for battery
materials in EVs today?
A non-academic perspective on applied battery research - M. J. Lacey 6
Typical lab experiment Volkswagen id.3 battery cell (NMC721)
Energy density, rate capability
Energy density, cycle life/efficiency
Energy density, rate capability, cycle life/efficiency
Other differences include: active material quality, particle size/PSD, electrolyte composition/additives, separators,
coating/calendaring methods, effects of temperature changes, pressure, heterogeneity at large scale… etc etc
What is transferable from lab experiments to practical understanding?
Günter and Wassiliadis, J. Electrochem. Soc. 169, 030515 (2022)

7. What sort of findings might and might not transfer from
e.g. typical lab coin cell to EV cell?
Assuming typical lab coin cell means: thin electrodes, excess conductive additive/binder, higher
porosity, excess electrolyte, excess N/P (or huge excess of Li metal)…
A non-academic perspective on applied battery research - M. J. Lacey 7
Maybe:
• Relative effects of different limitations on
performance
• Material-specific insights (properties,
mechanisms, chemistries)
• Opportunities for further improvements
• …
Maybe not:
• Accurate predictions of specific
capacity/energy, energy density,
power capability, cycle life, efficiency,
resistance increase, thermal
behaviour, safety…

8. “When are we getting the super battery?”
A non-academic perspective on applied battery research - M. J. Lacey 8

9. “The risk of excessive extrapolation”
• Excessive extrapolation – inappropriate inferences of future
performance outside the scope of the experiment
• Can be the fault of editors, journalists, PR communicators… but often
starts in the journal article, often unknowingly (sometimes knowingly)
• Unfortunately, this is actively incentivised by journals, funding
agencies, universities…
Effects
• Excessive extrapolation – or hype – wastes time, misallocates
resources, misleads policy, harms the integrity and reputation of the
field and industry
• Science is not necessarily self-correcting, it is much harder to refute
hype than it is to create it
A non-academic perspective on applied battery research - M. J. Lacey 9

10. We (mostly) acknowledge this is extremely widespread,
but what are we going to do about it?
A non-academic perspective on applied battery research - M. J. Lacey 10
If industry (and other sectors) lose trust in academic research, real world impact (not measured by citations,
or JIF) will only decrease!
Some potential steps forward:
• Data reporting standards (as adopted by
some journals)
• Publication of raw datasets and analysis
scripts (using repositories such as Zenodo)
• Explicit “limitations of the study” section, as
adopted in other research fields
• …resist the temptation to make far-reaching
claims about the future!
Johansson et al., Batteries and Supercaps 4, 12, 1785 (2021)

11. Good science has lasting impact,
hype does not
A non-academic perspective on applied battery research - M. J. Lacey 11
• For example; first report of
LiCoO2 by Goodenough’s
group
• Single most significant
material development leading
to first Li-ion batteries?
• 7 pages, 4 figures, 1 table…
• No hype!
• Legacy: multi-billion dollar
industry, Nobel Prize
Mizushima et al, Mat. Res. Bull. 15, 783 (1980)

12. How can we
bridge the gap?
A non-academic perspective on applied battery research - M. J. Lacey 12
Image copyright: Blend Images - Fotolia

13. Critical, ‘big picture’ perspectives
A non-academic perspective on applied battery research - M. J. Lacey 13
Many good examples of academic reviews/perspectives which look at the trajectory of a
development of a technology and critique its prospects in an objective and balanced manner

14. Differences in scale
A non-academic perspective on applied battery research - M. J. Lacey 14
20xx-format coin cell, NMC/Li
• 15 mm diameter electrode
• 1 mAh/cm²
• ~11 mg CAM
Scania urban transport electric truck, 300 kWh
installed
How much more CAM than the lab coin cell?
• 4,500 ×
• 450,000 ×
• 4,500,000 ×
• 45,000,000 ×

15. The gap (and the difference) between theory and system
A non-academic perspective on applied battery research - M. J. Lacey 15
Representative example, based on graphite-SiOx || NCA cylindrical cells
2390
Wh/L
1865
Wh/L
675
Wh/L
270
Wh/L
theory ‘reversible’ cell battery pack
materials chemistry engineering

16. The gap between theory and system is not necessarily
the same for different chemistries
A non-academic perspective on applied battery research - M. J. Lacey 16
Image: Tesla Motors club user wk057
Image: BYD

17. Differences in metrics
A non-academic perspective on applied battery research - M. J. Lacey 17
KPI Common academic metrics Common industry-relevant
metrics
Capacity/energy mAh/g
Wh/kg (theoretical, material,
stack)
mAh/cm2, mAh/cm3
Wh/kg, Wh/L (cell, system)
Power C-rate (mA/g)
Z(ω) (Ω)
W
mA/cm²
DCIR/HPPC(I, t) (Ω)
Charging time C-rate Minutes/hours (e.g. 10-80% SoC)
Lifetime No. of cycles Full cycle equivalents (FCE)
Total energy throughput (MWh)
Storage time, days (100% SoC)
Cost $/kg (material) $/kWh (cell, system), incl. EoL
value
Safety Flammability test
J/g (DSC)
Decomposition temp (TGA)
EUCAR HL, propagation time,
maximum temperature, gas
volume/composition

18. Development is also affected by market factors and
government policy
A non-academic perspective on applied battery research - M. J. Lacey 18
• In 2019, China's subsidy regime was tightened, meaning EVs with a battery pack of less than 120Wh/kg, would
get no subsidy. This meant LFP packs, which had a max ED of 120Wh/kg, no longer received a subsidy.
• Even high energy density packs received a lower subsidy on a $ basis, as the total subsidy level was reduced as
well as the subsidy multiplier.
100% 100%
110% 110% 110%
0%
60%
100%
110%
120%
0% 0%
80%
90%
100%
90-105 105-120 120-140 140-160 160 and above
Wh/kg
2017
2018
2019
Chinese EV subsidy
BloombergNEF, China Slashes EV Subsidies by Half

19. Ultimately, it is always about the money
A non-academic perspective on applied battery research - M. J. Lacey 19
• Technological advances are generally only adopted if they are lower cost than the incumbent technology
or have a viable cost-down trajectory.
BloombergNEF, 2022 Lithium-Ion Battery Price Survey

20. What can we do?
As academics:
• Be critical about the use of metrics
• Make research as reproducible as
possible
• Don’t oversell! Be realistic,
transparent, communicate
honestly. Stop the hype!
As industry scientists:
• Look for opportunities to
communicate to the academic
community (patents, end-user
requirements…)
• Support curiosity-driven research
which addresses fundamental
understanding
A non-academic perspective on applied battery research - M. J. Lacey 20
Collaborate:
• Seek input from people outside your area/sector!
• Identify common goals, understand mutual expertise/capabilities, take
advantage of opportunities… understand limitations and prerequisites

21. Long-lasting academic-industry collaboration in Sweden
A non-academic perspective on applied battery research - M. J. Lacey 21
“Li-cluster” “Fast charging project” “ALINE” “HALIBATT”
2009 2026
• Now in its fourth phase, Swedish automotive industry and battery research groups have long
productively collaborated on understanding degradation mechanisms in practical batteries
Automotive LFP cells Fast charging of energy-
optimized automotive cells
Automotive cells w/ Ni-rich
NMC electrodes
Heterogeneous degradation
in large format cells
• Shared problems/common scientific goals, complementary expertise/capabilities,
progression of findings/experience into continuation projects
• Several participants from the academic side joined ultimately joined the industry
• Applied research not just about trying to develop new technology – also about better
understanding existing or imminent technology

22. Summary
• Battery research in the lab and batteries in EVs have a lot in
common, but a lot of differences
• Beware the risks of excessive extrapolation/hype!
• Efforts towards better transparency, reproducibility, integrity will
always be worth it
• You don’t have to be an expert in everything, but it helps to keep
the bigger picture in mind
• Academic-industrial collaboration is not just about
commercialising academic research
A non-academic perspective on applied battery research - M. J. Lacey 22

23. The correct answer…
A non-academic perspective on applied battery research - M. J. Lacey 23
~45,000,000 × more CAM in the truck than the coin cell!