5
water dripping from their roofs, an LIB could be exposed to
flooding due to water dripping onto a piece of equipment
for an extended period. In addition, some underground
mines have pools of water throughout, and water could be
splashed onto an LIB as the operator drives through the
water. In late 2022, flooding associated with Hurricane Ian
led to LIB-powered golf cart fires [30, 31]. As flood waters
receded, numerous golf carts caught fire due to internal
shorting or reactions caused by saltwater entering the golf
cart batteries. Fires were observed on October 16, 2022 and
November 19, 2022, destroying 71 of 72 LIB-powered golf
carts.
Extreme cold temperature tests subject the cell, module,
or pack to conditions that could lead to dendrite formation
[29]. Only U.S. Advanced Battery Consortium standard
SAND99-0497 calls for an extreme cold temperature test.
In this test, an LIB is charged at its normal charge rate and
subsequently discharged to 80%, 50%, 40%, 20%, and 0%
SOC at temperatures of -40°C (-40°F), -20°C (-4°F), 0°C
(32°F), and 25°C (77°F). The test is stopped if damage is
observed.
The research discussed above highlights several mining-
environment-related concerns for LIBs. LIBs are prone to
dendrite growth during charging, and dendrite growth
rate and morphology depend on charging temperature.
The presence of dendrites combined with high mechanical
shock and vibration levels could result in damage to the
separator, possibly leading to an internal short circuit and
TR. LIB vibration response is affected by SOC. Therefore,
the damage caused by mechanical shock and vibration
depends on SOC. Over time, mechanical shock and vibra-
tion could cause microscopic cracks that might allow mine
water to enter an LIB housing. Further, condensation on
an LIB in a cold, high relative humidity (RH) environment
might cause water droplets to form, and cracks in an LIB
case could allow dripping water to enter. In addition, an
LIB could be dropped when it is being installed or swapped
out. The shock and impact loading due to dropping the
battery pack could immediately damage internal compo-
nents or cause microscopic cracks in the LIB case. Based
on these concerns, LIBs intended for use in mine vehicles
should be subjected to a comprehensive test procedure that
includes a drop test mechanical shock and vibration tests
across ranges of SOC, temperature, and RH, and, possibly,
an immersion test. The immersion test should be applied to
an LIB after it has undergone the drop test and mechanical
shock and vibration tests because these tests could cause
cracks in a battery case that might allow water to enter.
ENVIRONMENTAL SUSCEPTIBILITY OF
MINE UTILITY VEHICLE AND RUBBER-
TIRED MANTRIP LITHIUM-ION BATTERIES
Due to the potential widespread use of LIBs in MUVs
and RTMs in the near future and concerns with adverse
mine-related effects on LIBs, the National Institute for
Occupational Safety and Health (NIOSH) is launching a
project to examine these concerns. The project is planned
as a four-year effort that started on October 1, 2023. The
objective of the project is to determine the susceptibility of
MUV and RTM LIBs to environmental factors associated
with mining, such as mechanical shock, vibration, temper-
ature, moisture, and immersion, and to provide informa-
tion related to protecting LIBs from these environmental
factors.
The MUV/RTM LIB project has five specific aims:
1. To characterize the environmental conditions that
LIBs would be exposed to while in use on MUVs
and RTMs
2. To identify existing environmental test standards
for LIBs that could be applied to LIBs used on
MUVs and RTMs
3. To develop an environmental test procedure to
evaluate LIBs used on MUVs and RTMs
4. To determine the susceptibility of MUV and RTM
LIBs to environmental conditions associated with
mining
5. To determine how to protect MUV and RTM
LIBs from the environmental factors associated
with the mining environment.
Each of the above will be discussed below.
Characterize MUV/RTM Environmental Conditions
Knowledge of the operating conditions for MUVs and
RTMs is critical to assessing LIBs’ ability to withstand min-
ing environment conditions. The project team will work
with collaborating mines, equipment manufacturers, and
battery suppliers to collect operating data in surface and
underground mines across all commodities. Collecting data
at mines across the country ensures that all mining condi-
tions are represented.
Environmental data recorders and rugged data acqui-
sition equipment will be used to collect operating data.
The main parameters of interest are mechanical shock and
vibration, temperature, and relative humidity. In addition,
parameters such as travel speed and incline angle will also be
acquired. After installing the data acquisition equipment,
water dripping from their roofs, an LIB could be exposed to
flooding due to water dripping onto a piece of equipment
for an extended period. In addition, some underground
mines have pools of water throughout, and water could be
splashed onto an LIB as the operator drives through the
water. In late 2022, flooding associated with Hurricane Ian
led to LIB-powered golf cart fires [30, 31]. As flood waters
receded, numerous golf carts caught fire due to internal
shorting or reactions caused by saltwater entering the golf
cart batteries. Fires were observed on October 16, 2022 and
November 19, 2022, destroying 71 of 72 LIB-powered golf
carts.
Extreme cold temperature tests subject the cell, module,
or pack to conditions that could lead to dendrite formation
[29]. Only U.S. Advanced Battery Consortium standard
SAND99-0497 calls for an extreme cold temperature test.
In this test, an LIB is charged at its normal charge rate and
subsequently discharged to 80%, 50%, 40%, 20%, and 0%
SOC at temperatures of -40°C (-40°F), -20°C (-4°F), 0°C
(32°F), and 25°C (77°F). The test is stopped if damage is
observed.
The research discussed above highlights several mining-
environment-related concerns for LIBs. LIBs are prone to
dendrite growth during charging, and dendrite growth
rate and morphology depend on charging temperature.
The presence of dendrites combined with high mechanical
shock and vibration levels could result in damage to the
separator, possibly leading to an internal short circuit and
TR. LIB vibration response is affected by SOC. Therefore,
the damage caused by mechanical shock and vibration
depends on SOC. Over time, mechanical shock and vibra-
tion could cause microscopic cracks that might allow mine
water to enter an LIB housing. Further, condensation on
an LIB in a cold, high relative humidity (RH) environment
might cause water droplets to form, and cracks in an LIB
case could allow dripping water to enter. In addition, an
LIB could be dropped when it is being installed or swapped
out. The shock and impact loading due to dropping the
battery pack could immediately damage internal compo-
nents or cause microscopic cracks in the LIB case. Based
on these concerns, LIBs intended for use in mine vehicles
should be subjected to a comprehensive test procedure that
includes a drop test mechanical shock and vibration tests
across ranges of SOC, temperature, and RH, and, possibly,
an immersion test. The immersion test should be applied to
an LIB after it has undergone the drop test and mechanical
shock and vibration tests because these tests could cause
cracks in a battery case that might allow water to enter.
ENVIRONMENTAL SUSCEPTIBILITY OF
MINE UTILITY VEHICLE AND RUBBER-
TIRED MANTRIP LITHIUM-ION BATTERIES
Due to the potential widespread use of LIBs in MUVs
and RTMs in the near future and concerns with adverse
mine-related effects on LIBs, the National Institute for
Occupational Safety and Health (NIOSH) is launching a
project to examine these concerns. The project is planned
as a four-year effort that started on October 1, 2023. The
objective of the project is to determine the susceptibility of
MUV and RTM LIBs to environmental factors associated
with mining, such as mechanical shock, vibration, temper-
ature, moisture, and immersion, and to provide informa-
tion related to protecting LIBs from these environmental
factors.
The MUV/RTM LIB project has five specific aims:
1. To characterize the environmental conditions that
LIBs would be exposed to while in use on MUVs
and RTMs
2. To identify existing environmental test standards
for LIBs that could be applied to LIBs used on
MUVs and RTMs
3. To develop an environmental test procedure to
evaluate LIBs used on MUVs and RTMs
4. To determine the susceptibility of MUV and RTM
LIBs to environmental conditions associated with
mining
5. To determine how to protect MUV and RTM
LIBs from the environmental factors associated
with the mining environment.
Each of the above will be discussed below.
Characterize MUV/RTM Environmental Conditions
Knowledge of the operating conditions for MUVs and
RTMs is critical to assessing LIBs’ ability to withstand min-
ing environment conditions. The project team will work
with collaborating mines, equipment manufacturers, and
battery suppliers to collect operating data in surface and
underground mines across all commodities. Collecting data
at mines across the country ensures that all mining condi-
tions are represented.
Environmental data recorders and rugged data acqui-
sition equipment will be used to collect operating data.
The main parameters of interest are mechanical shock and
vibration, temperature, and relative humidity. In addition,
parameters such as travel speed and incline angle will also be
acquired. After installing the data acquisition equipment,