3
them into thermal runaway. Most of the containers were
fabricated from schedule 80 steel pipe except for the largest
6-in diameter pipe which used schedule 40. The additional
containers include the 1.5-in, 2-in, 2.5-in, 3-in, and 4-in
diameter pipes (Figure 2). In addition, an insert was fab-
ricated for the 2-in pipe to accept the size of the 18650
cells and displace additional free space. The internal vol-
umes were measured by filling the containers with water,
including the fittings, and pouring out the water into bea-
kers (Table 2).
The threaded caps were drilled and tapped to include
compression fittings on the caps to allow for venting gases,
measuring pressure and voltage, and inserting thermocou-
ples. One cell was placed within each sealed container per
test. In addition, one set of tests used three cells wired in
series and placed in a 1,175-ml canister (Figure 3).
N-type thermocouples were placed on the outside wall
of the canister, and when enough space was available, they
were placed inside the canister to measure the temperature
of the gases and the surface temperature of the cell. Several
pressure transducers were used from 30 psi to 3,000 psi
maximum pressure depending on expected pressures. The
thermocouples, battery leads, and a pressure transducer
were connected to the ARC system and samples were taken
every 0.6 seconds. The pressure transducer connected to the
DataQ system met the requirement of the MSHA explo-
sion testing at 100 samples per second. Each set of test
conditions was conducted three times, resulting in 24 total
tests conducted. A diagram of the test setup is shown in
Figure 4.
RESULTS AND DISCUSSION
Cell Composition
The cell was examined to confirm the anode composi-
tion specified by the manufacturer and to evaluate other
components, including the cathode and separator. The
analysis of the anode showed that the major elements
were titanium and oxygen (Figure 5a) consistent with the
Figure 1. Accelerating Rate Calorimeter
Table 2. Internal volumes of various canisters
Canister Diameter, in. 1.5 2 +insert 2 2.5 3 4 6
Internal Volume, ml 71 109 185 284 702 1175 2795
Figure 2. Containers provided various amounts of free space
Figure 3. An example of a triple LTO cell test in the 1,175-
ml container
them into thermal runaway. Most of the containers were
fabricated from schedule 80 steel pipe except for the largest
6-in diameter pipe which used schedule 40. The additional
containers include the 1.5-in, 2-in, 2.5-in, 3-in, and 4-in
diameter pipes (Figure 2). In addition, an insert was fab-
ricated for the 2-in pipe to accept the size of the 18650
cells and displace additional free space. The internal vol-
umes were measured by filling the containers with water,
including the fittings, and pouring out the water into bea-
kers (Table 2).
The threaded caps were drilled and tapped to include
compression fittings on the caps to allow for venting gases,
measuring pressure and voltage, and inserting thermocou-
ples. One cell was placed within each sealed container per
test. In addition, one set of tests used three cells wired in
series and placed in a 1,175-ml canister (Figure 3).
N-type thermocouples were placed on the outside wall
of the canister, and when enough space was available, they
were placed inside the canister to measure the temperature
of the gases and the surface temperature of the cell. Several
pressure transducers were used from 30 psi to 3,000 psi
maximum pressure depending on expected pressures. The
thermocouples, battery leads, and a pressure transducer
were connected to the ARC system and samples were taken
every 0.6 seconds. The pressure transducer connected to the
DataQ system met the requirement of the MSHA explo-
sion testing at 100 samples per second. Each set of test
conditions was conducted three times, resulting in 24 total
tests conducted. A diagram of the test setup is shown in
Figure 4.
RESULTS AND DISCUSSION
Cell Composition
The cell was examined to confirm the anode composi-
tion specified by the manufacturer and to evaluate other
components, including the cathode and separator. The
analysis of the anode showed that the major elements
were titanium and oxygen (Figure 5a) consistent with the
Figure 1. Accelerating Rate Calorimeter
Table 2. Internal volumes of various canisters
Canister Diameter, in. 1.5 2 +insert 2 2.5 3 4 6
Internal Volume, ml 71 109 185 284 702 1175 2795
Figure 2. Containers provided various amounts of free space
Figure 3. An example of a triple LTO cell test in the 1,175-
ml container