Sabine Arnold, Tam Nguyen, Sabine Arnold, Tam Nguyen, Sabine Arnold, Tam Nguyen, Sabine Arnold, Tam Nguyen, RagavendraRagavendraRagavendraRagavendra Arunachala, Andreas JossenArunachala, Andreas JossenArunachala, Andreas JossenArunachala, Andreas Jossen

Study of Inhomogeneity in Large Format Li-Ion Cells

with different Multiphysics Models

Study of Inhomogeneity in

Large Format Li-Ion Cells with

different Multiphysics Models

TUM CREATE Research Team

Sabine Arnold 2

Why Battery Cell Simulation

Sabine Arnold 3

• Understanding of battery

characteristics

• Insight into experimentally hard

to determine data

• Design of new cells:

• Easier

• Cheaper

• Safer

• Reduce time to market

Outline

Sabine Arnold 4

• Motivation

• Modelling Theory

• Experiment and

Model Validation

• Results & Discussion

• Conclusion & Outlook

Electrochemical Model

Sabine Arnold 5

Cathode Anode

Solid-state

diffusion

Reaction

kinetics

Charge

transfer

Solid-state

diffusion

Reaction

kinetics

Charge

transfer

Mass -

transport

Electrochemical potential

Electrochemical Model

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Layer Level

Reaction kinetics

Local current density

Electrode Potential

Electrolyte Potential

Ion transport in electrolyte

Ion transport in electrodes

Governing equationsGoverning equationsGoverning equationsGoverning equations

Anode: LixC6

Cathode: Lix(NikMnlCo1-k-l)O2

Electrolyte: LiPF6/EC/EMCCurrent Collectors: Al+/Cu-63Ah; 4.2V@SOC = 100%

LiLiLiLi----ion Pouch Cell Propertiesion Pouch Cell Propertiesion Pouch Cell Propertiesion Pouch Cell Properties TTTT---- & SOC& SOC& SOC& SOC----dependenciesdependenciesdependenciesdependencies

Thermal Model

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�����

��� �∆� � �

� � � ��� � ����

� ��� � ����������� ���� ��

���∆�

Energy balanceEnergy balanceEnergy balanceEnergy balance

Irreversible/ohmic heat Irreversible/entropic heat

Heat generation

Different Model Scales and Dimensions

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1D Newman 3D electrode

sandwich

Full 3D Model

(fully coupled and purely thermal)

Solver Settings

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Expected inhomogeneity Expected inhomogeneity Expected inhomogeneity Expected inhomogeneity

in domains in domains in domains in domains

� No average coupling

� Identity mapping

coupling operator

Highly nonlinear governing Highly nonlinear governing Highly nonlinear governing Highly nonlinear governing

equationsequationsequationsequations

� Relative tolerance:

1e-4

� Manually scaled

dependent variables

� Nonlinear method:

Constant (Newton),

Jacobian update on

every iteration

Full 3D and 3D ES CouplingFull 3D and 3D ES CouplingFull 3D and 3D ES CouplingFull 3D and 3D ES Coupling

Mesh

10

Mesh elementsMesh elementsMesh elementsMesh elements

1D Newman1D Newman1D Newman1D Newman 48

3D ES3D ES3D ES3D ES 5448

Full 3DFull 3DFull 3DFull 3D 195932

Thermal 3DThermal 3DThermal 3DThermal 3D 322524

Experiment and Validation

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CommandCommandCommandCommand ParameterParameterParameterParameter LimitLimitLimitLimit

Charge I = 1CA

U = 4.2 V

I< 0.05 CA

Pause 3 h

Discharge I = 0.5, 1, 2, 3 C

U= 2.7 V

I < 0.05 CA

Temperature T = 15, 25 & 40°C

Cell Voltage

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Surface Temperature Development

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Surface Temperature Distribution

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Surface measurement

Full 3Dcoupled

Full 3Dpurely

thermal

Normalized Current Distribution at t=1150s

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[A/m2]

Full 3D coupledcenter anode

Full 3D coupledtop cathode

3D electrode sandwichadiabatic discharge

anode

Temperature Distribution at end of 3C discharge

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°C

cell center top surface

Cross Plane Temperature Distribution at end of 3C discharge

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[°C]

with bottom cooling plate Convection boundary conditions

Computation

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Solution Solution Solution Solution

time [s]time [s]time [s]time [s]

Physical Physical Physical Physical

memory memory memory memory

[GB][GB][GB][GB]

Virtual Virtual Virtual Virtual

memory memory memory memory

[GB][GB][GB][GB]

Mesh Mesh Mesh Mesh

elementselementselementselements Model added valueModel added valueModel added valueModel added value GeometryGeometryGeometryGeometry

1D 1D 1D 1D

NewmanNewmanNewmanNewman 85 1.1 1.24 48

+ fast validation

electrochemical model

3D ES3D ES3D ES3D ES 1554 3.3 3.69 5448

+ in plane temperature and

current distribution

+ sufficient for adiabatic

conditions (coupled model

validation)

+ 10x faster than full model

Full 3DFull 3DFull 3DFull 3D 28097 70.44 75.94 195932

+ cross- and in- plane

temperature and current

distribution

Thermal Thermal Thermal Thermal

3D3D3D3D 28322 77.34 78 322524

- temperature only

- assumes uniform current

distribution

+ considers temperature

dependency of internal

resistance

Conclusion

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Simulation Models Simulation Models Simulation Models Simulation Models

provide hard to measure provide hard to measure provide hard to measure provide hard to measure

informationinformationinformationinformation:

• Cross plane

temperature

• Current distribution

• Inhomogeneity in Inhomogeneity in Inhomogeneity in Inhomogeneity in

current and current and current and current and

temperature cause temperature cause temperature cause temperature cause

• accelerated ageing

• performance

reduction

• safety issues

Thank you for your attention!

Sabine Arnold 20

Do not hesitate to contact me:

sabine.arnold@tum-create.edu.sg

References

M. Doyle, T.F. Fuller, J. Newman, Modeling of Galavanostatic Charge and Discharge of of the Lithium/Polymer/Insertion Cell, J. Electrochem. Soc.,

140140140140, 1526-1533 (1994)

J. Newman, K.E. Thomas-Alyea, Electrochemical Systems, 535ff. John Wiley & Sons Inc., Hoboken, New Jersey (2004)

D. Bernardi, G. Pawlikowski, J.Newman; A General Energy Balance for Battery Systems; J. Electrochem. Soc., 132132132132, 5-12 (1985)

P. J. Osswald, S. V. Erhard, J. Wilhelm, H. E. Hoster, and A. Jossen, Simulation and Measurement of Local Potentials of Modified Commercial

Cylindrical Cells: I. Cell Preparation and Measurements, J. Electrochem. Soc. 162(10)162(10)162(10)162(10), A2099-A2105, (2015)

C. Wang V. Srinivasan, Computational battery dynamics (CBD)–electrochemical/ thermal coupled modeling and multi-scale modeling, Journal of

power sources, 110110110110, no. 2, 364–376 (2002)

V. Srinivasan, C. Wang, Analysis of Electrochemical and Thermal Behavior of Li-Ion Cells, J. Electrochem. Soc., 150150150150, (1) A98-A106 (2003)

G.-H. Kim, A. Pesaran, and R. Spotnitz, A three-dimensional thermal abuse model for lithium-ion cells, Journal of Power Sources, 170, no. 2, 476-

489, (2007)

R. Arunachala, S. Arnold, L. Moraleja, T. Pixis, A. Jossen, J. Garche; 2015; Influence of Cell Size on Performance of Lithium Ion Battery; Oral

presentation at Advanced Battery Power Conference Aachen (2015)

S. G. Stewart, V. Srinivasan, J. Newman, Modeling the Performance of Lithium-Ion Batteries and Capacitors during Hybrid-Electric-Vehicle

Operation, J. Electrochem. Soc., 155155155155, (9) A664-A671 (2008)

M. Ecker, S. Käbitz, I. Laresgoiti, D. U. Sauer, Parameterization of a Physico-Chemical Model of a Lithium-Ion Battery, J. Electrochem. Soc., 162162162162, (9)

A1849-A1857 (2015)

L. O. Valǿen, J. N. Reimers, Transport Properties of LiPF6-Based Li-Ion Battery Electrolytes, J. Electrochem. Soc., 152152152152, (5) A882-A891 (2005)

M. Safari, C. Delacourt, Modeling of a Commercial Graphite/LiFePO4 Cell, J. Electrochem. Soc., 158,158,158,158, (5) A562-A571 (2011)

S. Du, M. Jia, Y. Cheng, Y. Tang, H. Zhang, L. Ai, K. Zhang, Y. Lai, Study on the thermal behaviors of power lithium iron phosphate (LFP)aluminum-

laminated battery with different tab configurations, International Journal of Thermal Sciences, 89,89,89,89, 327-336 (2015)

A. Nyman, M. Behm, G. Lindbergh, Electrochemical characterisation and modelling of the mass transport, Electrochimica Acta, 53,53,53,53, 356–6365 (2008)

T.G. Zavalis, M. Behm, G. Lindberg, Investigation of Short-Circuit Scenarios in a Lithium-Ion Battery Cell, J. Electrochem. Soc., 159159159159, (6) A848-A859

(2012)

Sabine Arnold 21

Summary

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Solution Solution Solution Solution

time [s]time [s]time [s]time [s]

Physical Physical Physical Physical

memory memory memory memory

[GB][GB][GB][GB]

Virtual Virtual Virtual Virtual

memory memory memory memory

[GB][GB][GB][GB]

Mesh Mesh Mesh Mesh

elementselementselementselements Model added valueModel added valueModel added valueModel added value GeometryGeometryGeometryGeometry

1D 1D 1D 1D

NewmanNewmanNewmanNewman 85 1.1 1.24 48

+ fast validation

electrochemical model

3D ES3D ES3D ES3D ES 1554 3.3 3.69 5448

+ in plane temperature and

current distribution

+ sufficient for adiabatic

conditions (coupled model

validation)

+ 10x faster than full model

Full 3DFull 3DFull 3DFull 3D 28097 70.44 75.94 195932

+ cross- and in- plane

temperature and current

distribution

Thermal Thermal Thermal Thermal

3D3D3D3D 28322 77.34 78 322524

- temperature only

- assumes uniform current

distribution

+ considers temperature

dependency of internal

resistance