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Fire Hazards of Lithium Ion Batteries
FEDERAL AVIATION ADMINISTRATION
Aviation Research Division
William J. Hughes Technical Center
Atlantic City International Airport, NJ 08405
*Department of Fire Protection Engineering,
University of Maryland, College Park
International Aircraft Systems Fire Protection Working Group Meeting
Dresden, Germany, May 12-13, 2015
WEB: www.fire.tc.faa.gov E-MAIL: richard.e.lyon@faa.gov
Richard E. Lyon, Richard N. Walters, Sean Crowley,
and *James G. Quintiere
Objective: Measure Fire Hazards of LIBs
Passenger electronics
Typical
packaging
Typical bulk shipment as cargo
Causes of Battery Failure
• Thermal
– Separator melts due to high temperature causing internal short circuit that releases heat.
– Contents mix, react and thermally decompose.
• Electrical
– Overcharge
– Rapid discharge
• Mechanical
– Physical damage (puncture)
– Manufacturing defect or contaminant
All lead to auto-accelerating heat
generation and rapid temperature
increase (Thermal Runaway) leading
to fire and/or explosion
< 1 second
Materials: Commercial 18650 LIB Cells
65 mm
18650 Rechargeable Cells ( 44 grams each)
18 mm
Electrical Properties of Tested Cells
LiMn2O4-LiNiCoO2
LiCoO2
LiNiCoAlO2
Unknown
Cathode
Maximum
Capacity,Qmax
(A-s)
11,700
9,400
5,400
18,000
Rated
11,200
8,300
5,000
3,600
Actual
Cell Potential,
(V) -∆G, Qmax
(kJ/cell)
41
31
19
13
3.6
3.7
3.7
3.7
Nominal
4.1
4.1
4.1
4.0
Max.
State-of-Charge, SOC = Q/Qmax
Chemical Energy Available to Do Useful Work (Free Energy), ∆G = -Q
Experimental Methods: Cell Charging
• Charge / Discharge 4 cells simultaneously
• Record: charge / discharge capacity
• Programmable for different states of charge
Methods: Hazard Measurements
Thermal Effects of Cell Failure Purpose-Built Thermal Capacitance
(Slug) Calorimeter
Energetics of Cell Failure ASTM D 5865-14, Standard Test Method for
Gross Calorific Value of Coal and Coke
Fire Behavior of Lithium Cells (ASTM E 1354, Standard Test Method for Heat and Visible
Smoke Release Rates for Materials and Products Using an
Oxygen Consumption Calorimeter)
Bomb Calorimeter (ASTM D 5865)
• Parr Instruments Model 1341 Plain Jacket Oxygen Bomb Calorimeter
• Resistance heating to force thermal runaway of LIBs
• Nitrogen blanket (1 Atm) to prevent oxidation of contents after failure
• Temperature, voltage and current logged for all tests
Bomb and other components
for 18650 battery tests
Experimental Setup
Thermodynamics of Cell Failure
Energy released by mixing, chemical
reaction and thermal decomposition
of cell components.
UTotal Urxn Q
Total energy
released at cell
failure
(measured in bomb)
Electrochemical (Free) energy release
(Calculable from cell potential (V) and
charge Q (A-s))
Depends on
cell chemistry
Analysis of Bomb Calorimeter Data
0
10
20
30
40
50
60
70
80
0 500 1000 1500 2000 2500 3000 3500 Energ
y R
ele
ase a
t F
ailu
re (
kJ/c
ell)
Charge, Q (mAh)
Free Energy, ∆G (Q)
Total Energy
(∆Utotal) Energy of Mixing, Reaction
and Decomposition, ∆Urxn
∆Urxn 90% of Q
LiMn2O4-LiNiCoO2 LiCoO2 LiNiCoAlO2 Unknown
18650 Cell Chemistry
80
70
60
50
40
30
20
10
0 0 10 20 30 40 50 60
LiMn2O4-LiNiCoO2
En
erg
y R
ele
ase
at F
ailu
re (
kJ/c
ell)
60
50
40
30
20
10
0
-10 0 5 10 15 20 25 30 35 40
LiCoO2
40
30
20
10
0
-10 0 5 10 15 20 25
LiNiCoAlO2
Electrochemical Free Energy, Q (kJ/cell)
30
25
20
15
10
5
0
-5 0 5 10 15 20
Unknown
∆Utotal
∆Urxn
Energetics of Individual Cell Failure
∆Utotal
∆Urxn
∆Utotal
∆Urxn
∆Utotal
∆Urxn
Fre
e E
nerg
y,
Q (
kJ/c
ell)
State of Charge, Q/Qmax (%)
LiMn2O4-
LiNiCoO2
LiCoO2
LiNiCoAlO2
Unknown
0
10
20
30
40
50
60
70
80
0 20 40 60 80 100 0
10
20
30
40
50
0 20 40 60 80 100
State of Charge, Q/Qmax (%)
Stored
Electrochemical
Energy (Q)
Total
Energy
(∆Utotal)
LiMn2O4-
LiNiCoO2
LiCoO2
LiNiCoAlO2
Unknown
Tota
l E
nerg
y, ∆
Uto
tal (
kJ/c
ell)
State-of-Charge is Not a Good Predictor of Energetics for
Different Chemistries and Cell Potentials
Li-Ion 18650 Batteries - Post Test
Zero Charge 50% Charged 100% Charged
Gravimetric Analysis for Volatile Yield
0
1
2
3
4
5
6
0 10 20 30 40 50
Vola
tile
Yie
ld,
g/c
ell
Electrochemical (Free) Energy, Q (kJ/cell)
• Bomb weighed before and after venting
to atmosphere to determine volatile yield
• Volatiles are combustible
• Yield Q
LiMn2O4-LiNiCoO2
LiCoO2
LiNiCoAlO2
Unknown
Infrared Spectra of Gaseous Decomposition Products
LiMn2O4-
LiNiCoO2
LiCoO2
LiNiCoAlO2
Unknown
Thermal Effects of Cell Failure
J.G. Quintiere & S.B. Crowley, Thermal Dynamics of 18650 Li-ion Batteries, The
Seventh Triennial International Fire & Cabin Safety Research Conference,
Philadelphia, PA, 2013.
20 g
2 s
600C
2 s
Separator
Melts (150C)
Venting (200C)
Failure (250C)
0
10
20
30
40
50
0 10 20 30 40 50
Therm
al E
nerg
y q
b, kJ/c
ell
Stored Free Energy, Q (kJ/cell)
1
1
Thermal Energy Release (qb) Free Energy (Q)
Implies chemical reactions of electrolytes
(∆Urxn) take place outside of cell when
contents are ejected
0
200
400
600
800
1000
1200
1400
0 20 40 60 80 100
Maxim
um
Cell
Surf
ace
Te
mpera
ture
, T
ma
x (C
)
State of Charge/SOC (%)
Tmax Tf Utotal
mcp
Tf Urxn
mcp
Q
mcp
Contents
Ejected,
∆Urxn 0,
Tmeas < Tcalc
Adiabatic (Surface) Temperature Rise
250CUrxn
mcp
Qmax
mcp
*SOC
100
Fire Calorimeter Testing of Lithium Cells
Special holder designed to
prevent rocketing of cell at failure
Standard ASTM E 1354 Operation
0
1
2
3
4
5
6
80 90 100 110 120 130 140 150
HR
R, kW
/cell
Elapsed Time, seconds
Original Data
HRR Corrected for 3-
second Response Time of
Cone Calorimeter
(Deconvoluted)
Heat Release Rate in Cone Calorimeter
5s
Venting
Failure
Failure is so rapid that HRR must be
corrected for cone calorimeter response
5s
5s
Flaming
Combustion of
Cell Contents
(75 kJ/cell)
Decomposition
Reactions
(14 kJ/cell)
Discharge of Stored
Electrochemical Energy
By Internal Short Circuit
(14 kJ/cell)
LiCoO2 Cell at 50% SOC
Fire and Thermal Hazards of 18650 Cell
Total 103 kJ/cell = 2.3 kJ/g 1/20 jet fuel
= 109 J/m3
75 kJ/cell
6.62 x 10-5 m3/ cell qv =
HRR (t ) qv
dV
dt qv
dL(t )3
dt 3qv (L0
)3t 2
Analytic Model of 18650 Cargo Fire Growth
L(t)
L(t)
L(t)
Combustion
Volume at time t,
V(t ) = L(t )3
L (18mm)(65mm) 34mmEffective Length of 18650,
Constant linear fire growth rate,
L 0 L
L 2
mc / 3x104 m /s
Heat Release in Flaming Combustion, qv = 109 J/m3
0
200
400
600
800
1000
1200
0 10 20 30 40 50 60 70
Heat R
ele
ase R
ate
, H
RR
(kW
)
Time After First Ignition, minutes
Battery Fire t 2 Model
(LiCoO2 18650, 50% SOC)
Full Scale Test Data
LiCoO2 18650, 50% SOC
(from O2 consumption)
H. Webster, May 2013
Full-Scale Test (Before) Full-Scale Test (After)
Model Versus Full Scale Test Data
Class E
Main Deck
Cargo
State-of-charge is a poor predictor of fire hazard for
different batteries and cell chemistries.
Total energy at failure of Li Ion cells/batteries (LIB), ∆Utotal
is almost twice the stored electrochemical energy Q for
the 18650 cell chemistries of this study.
Summary
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