BDS Overview

1. C
BD Battery Design LLC
Overview of Battery
Design S
Studio® with
Examples
Robert M. Spotnitz
M
rspotnitz@batdesign.com

2. C BD Battery Design Studio®
Battery Design LLC
y
A user-friendly interface
g
between battery designers
and users for costing, sizing,
and correlation of test data
to performance, safety, and
life predictions.
Development started APR1999
p
interface
i t f
Size
Lab Cost
Input
I t Power
Model Impedance
Output Data Life
Abuse, etc
Ab t
User
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3. Battery Design Studio®
C BD
Battery Design LLC
a standardized interface
Objective: Exchange of battery information.
Battery
Tests Designs
interface Data
D t
Analysis
Input
Input
Models
Output
Output
User Size, Cost, Power Colleague
Impedance, Life Battery developer
Abuse,
Abuse etc Cathode maker
Separator maker
Etc.

4. BDS Specification of Physical
C BD Design
Battery Design LLC
g
This is first attempt to standardize specifications for
lithium-ion battery components.

5. BDS is a platform for different
C BD models
Battery Design LLC
Different models can be applied to same cell design.

6. Example – Visualize data from
C BD different battery cyclers
Battery Design LLC
BDS provides tools to work with experimental and
simulated data.

7. C BD What BDS Provides
Battery Design LLC
Tools
• To analyze data
• To visualize cell designs
• To compare experiments with models
• To visualize model results
• Database
Standard platform for accessing design
programs and simulation models
A better way to design and develop
batteries
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8. C1)
2)
BD Features of BDS
Battery Design LLC
User-friendly interfaces for input of various cell designs (stack, spiral)
Visualization tools for examination of results
3) Cell sizing and costing
4) Database of components (active matls, electrolytes, separators, etc.)
5)
) Physics-based models
y
6) Circuit models
7) Testers – cycler, oven, ARC, DSC
8) Pack Design
9) Optimization/Regression routines for fitting model parameters to
experimental data - fits results from multiple cells and tests
simultaneously
10) Sensitivity Analysis – how parameter changes affect results
11) Verification – determine # of experiments necessary to obtain user-
specified confidence limit
12) Gap Analysis – determine suitability of a battery for an application
13) Security – encrypted files
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9. 1) User-friendly interface for
C BD
Battery Design LLC
cell design input
g p
Page 9

10. 2) Visualization tools for
C BD
Battery Design LLC
examination of results
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11. C BD
Battery Design LLC
3) Cell sizing and costing
) g g
Reports can be exported to Excel®
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12. C BD
Battery Design LLC
4) Database of components
) p
Create a new record
Save the current record
Delete the current record
Associate an information file w
when there is more detailed in
example, if a manufacturer’s d
l f t ’
as a pdf (or Word) file, that file
record.
Add notes about a record; te
00005 i
Multiple databases possible.
p p
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13. C BD
Battery Design LLC
5) Physics-based models
) y
Developers can add their own models.
p
Models can be proprietary.
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14. C BD Unit Cell Model (pseudo-2D)
Battery Design LLC
Anode Porous
(p )
Discharge Porous
Active Negative
N ti Separator Positive
φ2
Binder c
i2x
φ1 Li+
Cathode
Collector
Anode
Collector Cathode
Conductive
Active
Additive
cs jn 14
SEI

15. C BD Variables (c, i2, Φ2, Φ1, jn, cs)
Battery Design LLC
,
c − Liquid-phase salt concentration, mol m3
Liquid phase
i2 − Liquid-phase current density, A m 2
φ2 − Liquid-phase potential, Volts
φ1 − Solid-phase potential, Volts
p p ,
jn − Local current density at active surface, A m 2
cs − Solid- phase Li concentration, mol m3
Temperature will be considered later
15

16. C BD
Battery Design LLC
Liquid-phase ∂c
mass balanceε
Newman’s Dual Equations (c, i2,
Φ2, Φ1, jn, cs)
⎛ εD ⎞ i 2 ⋅ ∇t +
= ∇ ⋅⎜ ∇c ⎟ −
o
( )
⎛ d ln co ⎞
+ ajn 1 − t + , D = Do ⎜1 −
o
⎟
∂t ⎝ τ ⎠ F ⎝ d ln c ⎠
Solid-phase iset − i 2 = −σ∇φ1
Ohm’s law
2κRT ⎛ ∂ ln f A ⎞
Liquid-phase
i 2 = −κ∇φ2 +
F ⎝
⎜1 + (
∂ ln c ⎠
)
⎟ 1 − t + ∇ ln c
o
∂ (φ1 − φ2 )
Ohm’s law
1
Kirchoff’s law ajn + aC
Ki h ff’ l = − ∇ ⋅ i2
∂t F
Solid-phase
∂cs 1 ∂ r 2 N
= 2
( ), N = − Ds
∂cs
balance ∂t
mass b l r ∂r ∂r
α ⎧ ⎛ α Fη ⎞ ⎛ − α c Fη ⎞⎫
jn = Fk (c ) a (c1 − cs ) c (cs ) c ⎨exp⎜ a
α α
⎟ − exp⎜ ⎟⎬
Butler-Volmer ⎩ ⎝ RT ⎠ ⎝ RT ⎠⎭
η = φ1 − φ2 − U eq − jn Rsei
16

17. BD Modifications to
C BD Dual Model
Battery Design LLC
Coupled to sizing programs
p gp g
Temperature and concentration
dependent solid-phase diffusion
solid phase
coefficients
Multiple active materials
Side reactions (lithium deposition, self
discharge)
di h )
Choice of kinetics expressions (linear,
Tafel, Butler Volmer)
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18. Energy Balance for Insertion
C BD Electrode
L.
L Rao and J Newman J Echem. Soc Vol 144(8) 2697 (1997).
Battery Design LLC
cp
dT &
J. J. Echem Soc., Vol.
− Q = − ∫ ∑ ain ,lU H ,l dv − IV
(1997)
dt v l
v : volume
&
Q :rate of heat flow to environment
d ⎛ Ul ⎞
U H ,1 :enthalpy potential = −T 2
⎜ ⎟ ≈ Ul
dT ⎝T ⎠ Energy
U l :local open-circuit potential balance
over entire
V :closed-circuit potential cell
in ,l :local current density for reaction l
I : cell current
18

19. C BD
Battery Design LLC
6) Equiv. Circuit Models
) q
PNGV Circuit Model
Five parameters
OCV, OCV’
OCV OCV , Ro, Rp, C
Page 19

20. C BD
Battery Design LLC
PNGV Equiv. Circuit Model
q
Page 20

21. 7) Testers mimic actual
C BD q p
equipment
Battery Design LLC
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22. C BD 8) Pack Design
)
Battery Design LLC
g
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23. C BD
Battery Design LLC
9) Optimization/Regression
) p g
The objective of an optimization can
be to maximize/minimize a value of
the Report tab of a cell (“build
( build
optimization”) or the result of a test
(“test optimization”).
Test optimization is typically used to
regress model parameters to
experimental data.
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24. C BD
Battery Design LLC
9.1) Build Optimization
) p
Select
termination
conditions
Select
parameters
to optimize
Select
Double-
parameters
click on
to
t vary andd
“Target” to
set range of
activate
values to
pop-up
explore
p
window
i d
with
options
(
(see next
page)
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25. C BD
Battery Design LLC
Parameters
9.2) Regression
) g
specific to a
cell (as
opposed to
those
common to
all cells)
can be
selected here
Multiple procedures can be used to fit parameters.
Double-clicking on the Output column for the
procedure brings up “Options for Procedure” dialog.
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26. C BD Examples
Battery Design LLC
p
High-Power Cell Fit (Dual model)
g ( )
High-Energy Cell Fit
• Dual Model
• Circuit Model (Nelson)
• Pack Simulation
Page 26

27. C BD HPPC Simulation
Battery Design LLC
Cycle 1
Cycle 9
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28. Rate Capability test at 20oC –
C BD simulation versus experiment
Battery Design LLC
p
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29. Discharge at –30 °C
C BD
Battery Design LLC
Cell Voltage / V
- not met
4.5
45
Simulation
4
3.5
3
2.5
2
0 100 200 300
Time / min
Requirement not met (1.21 Ah < 1.33 Ah)
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30. Lithium-Ion Simulation with
C BD
Battery Design LLC
Empirical Models
Nelson model - extended
p
GP26L
T = Temperature(K), I = Current(amps) ⎛ ⎞
R o (T, I) = R 0 + R1 ⋅ T + R 2 ⋅ e R 5 ⋅T
+ R3 ⋅ e R 6 ⋅abs(I)
+ R 4 ⋅ abs(I) ⎜ ∂E ⎟
− V ⎟ I + h(Tamb − T )
dT
cp = ⎜ E −T
τ 1 = T10 ⋅ I + T11 , τ 2 = T20 ⋅ I + T21 dt ⎜ 1 24 ∂T ⎟
⎜ 4E 3 ⎟
OCV(DODe), DODe = A ⋅ DOD B ⎝ tn ⎠
A(T, I) = A 0 ⋅ e A1 (T − A3 ) + A 2 + A 4 ⋅ I
B(T, I) = B0 ⋅ e B1 (T − B3 ) + B2 + B4 ⋅ I Energy balance solved
DOD= DOD t = 0 +
∫ Idt simultaneously
Q max
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31. Comparison of Model to Data
C BD Voltage for C Discharge at 25°C
Battery Design LLC
g g
GP26L Cell
R2=0.958
Average e o = 3
e age error 32.1 mV
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32. Temperature for C Discharge at
C BD 25°C - Model versus Data
Battery Design LLC
R2=0.923
Average error = 0.82 oC
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33. 6A Discharge
C BD -Voltage
Battery Design LLC
g
Page 33

34. 6A Discharge
C BD - Pack Temperature
Battery Design LLC
p
Page 34

35. Comparison of Model to
C BD Thermal Image (10 A at 2.8 Ah)
Battery Design LLC
50oC
g ( )
21oC
Page 35

36. Comparison of Model to
C BD Thermal Image (10 A at 5.3 Ah)
Battery Design LLC
61oC
g ( )
22oC
Page 36

37. Comparison of Model to
C BD Thermal Image (10 A at 7.0 Ah)
Battery Design LLC
66oC
g ( )
22oC
Page 37

38. C BD Conclusion
Battery Design LLC
Use of Battery Design Studio® as a common
platform f analysis of b tt
l tf for l i f battery d t provides an
data id
unprecedented opportunity to accelerate battery
development by providing
p yp g
Program Managers with a standardized,
consistent, accessible means to evaluate and
monitor programs
Developers/Researchers with a user-friendly
means to analyze data and present results
A means to distribute data and models
(encrypted)
Page 38