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
Atlantic City, New Jersey, October 21-22, 2015
WEB: www.fire.tc.faa.gov E-MAIL: [email protected]
Richard E. Lyon, Richard N. Walters, Sean Crowley,
and *James G. Quintiere
Outline of Talk
Motivation: Safe Shipment of Batteries
Background: Lithium Ion Cells/Batteries
Methodologies
Findings
William J. Hughes Technical Center, Atlantic City, NJ
Fire Safety Research
Aircraft Fire Incidents Involving Li Batteries
• Fire erupted in a cargo plane that landed in Philadelphia on Feb. 7, 2006.
• A cargo plane with 81,000 lithium batteries caught fire and crashed after it left Dubai on Sept. 3, 2010.
• A cargo jet crashed into the East China Sea on July 28, 2011, after the crew reported a fire on board.
Objective: Measure Fire Hazards of LIBs
Passenger electronics
Typical
packaging
Bulk shipment as cargo
• Increasing applications
– More widely used
– Higher energy densities
• Modeling of Failure
(Thermal Runaway)
– Up to 6 decomposition
reactions
– CFD thermal-chemical-
electrical analyses
• Experimental Studies
– Component studies
– DSC, ARC studies
Applications and Industry Research
Electronics Cars
E-cigarettes
ARC
0
Lead-Acid
NI-Cd
Li-Titanate
NiMH
Li-Metal
(Non-rechargeble)
Zn-air (developmental)
Energ
y D
ensity,
kJ/c
m3
Specific Energy, kJ/g
Smaller
Lighter 0.5 1.0 1.5 2.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Energy Density and Cell Chemistry
Voluntary ban as cargo on
passenger flights by major airlines
Officially banned as cargo
on passenger aircraft by
FAA (2005) and
International Civil Aviation
Organization (ICAO) (2015)
Normal Discharge of Lithium Ion Cell
Copper Terminal
Graphite
Anode
Lithium Transition
Metal Oxide
Cathode
Aluminum Terminal
Electrolyte: Organic Ethers, Esters,Carbonates
(polymer = gel)
PE or PP
Membrane
Separator
Materials: Commercial 18650 LIB Cells
65 mm
18650 Rechargeable Cells ( 44 grams each)
18 mm
Causes of Battery Failure
• Electrical
– Overcharge
– Rapid discharge
• Mechanical
– Physical damage (puncture)
– Manufacturing defect or contaminant
• In Fires
– Separator melts due to high temperature causing internal short circuit that liberates heat.
– Contents mix, react and thermally decompose.
Thermal Runaway
• Auto-accelerating heat generation
• Rapid temperature increase
• Expulsion of flammable gases and liquids
< 1 second
Experimental Methods: Cell Charging
• Charge / Discharge 4 cells simultaneously
• Record: charge / discharge capacity
• Programmable for different states of charge
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
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)
• Standard Test Method for Gross Calorific Value of Coal and Coke
• 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
Cell Thermodynamics (see Paper)
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, ∆G
(Equal to cell potential (V) times
charge Q (A-s))
Depends on
cell chemistry
Baseline-Corrected Temperature History In Bomb
0
1
2
3
4
5
6
500 1000 1500 2000 2500 3000
Tem
pera
ture
Ris
e (C
)
Time (seconds)
100% 80%
50%
20%
0%
SOC
Generalized Energetics of Cell Failure
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 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)
SOC is a Poor Predictor of Energy Release 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
• 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)
Mass Loss
Temp. Rise
Maxim
um
Cell
Surf
ace
Tem
pera
ture
, T
ma
x (C
)
Tmax Tf Utotal
mcp
Adiabatic (Surface) Temperature Rise
0
200
400
600
800
1000
1200
1400
0 10 20 30 40 50 60
(R = 0.99528)
∆Utotal (kJ/cell)
LiCoO2 Cell
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, sec
Original Data
Corrected Data
HRR of 18650 LiCoO2 Cell in Cone
3 s
Venting Failure
HRR corrected for response time of cone calorimeter
3 s
Mass L
oss (
g/c
ell)
State of Charge, Q/Qmax (%)
Mass Loss of 18650 Cell in Fire Calorimeter Test
0
5
10
15
20
0 20 40 60 80 100
Gases Only
(from bomb calorimeter)
Gases + Liquids + Solids
(from fire calorimeter)
LiCoO2
Qmax = 2600 mAh
3.7V (nominal)
0
5
10
15
0 20 40 60 80 100
PH
RR
(kW
/cell)
or
HO
C (
kJ/g
-gas)
State-of-Charge/SOC (%)
Heat of Combustion
of Gases/HOC, kJ/g
Peak Heat Release
Rate/PHRR, kW/cell
PHRR and HOC for LiCoO2 18650 Cell
Flaming
Combustion of
Cell Contents
(75 kJ/cell)
Decomposition
Reactions
(14 kJ/cell)
Stored Electrochemical
Energy (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 LIB 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 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
Thermal Energy Released at Cell Failure of 18650 LIBs
(∆Utotal) is:
• Dependent on cell chemistry (voltage and capacity)
• Equal parts electrical (Q) and chemical (∆Urxn)
• Responsible for fire propagation
• Half of total fire hazard when combustion of contents is
included combustion.
Summary