Notice2021-21416
Denial of Motor Vehicle Defect Petition
Primary source
Metadata and text below are from the Federal Register, a public-domain U.S. government work. Always verify the official published version before relying on it for any legal matter.
Published
October 5, 2021
Issuing agencies
Transportation DepartmentNational Highway Traffic Safety Administration
Abstract
This notice sets forth the reasons for the denial of a petition submitted on September 17, 2019, by Mr. Edward Chen (the petitioner), requesting that the Agency "initiate a Defect Investigation into the recent set of software updates, including software updates 2019.16.1 and 2019.16.2 and all subsequent updates issued by Tesla, Inc. to its Model S and Model X vehicles, which have been alleged to be issued by Tesla in response to the alarming number of car fires that have occurred worldwide." On October 1, 2019, ODI opened Defect Petition DP19-005 to evaluate the petitioner's request. After reviewing the information provided by the petitioner, information provided by Tesla in response to an information request letter from NHTSA, and field data regarding non-crash vehicle fires in model year (MY) 2012 through 2019 Tesla Model S and Model X vehicles, NHTSA has concluded that the issues raised by the petition do not warrant a defect investigation at this time. Accordingly, the Agency has denied the petition.
Full Text
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<title>Federal Register, Volume 86 Issue 190 (Tuesday, October 5, 2021)</title>
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[Federal Register Volume 86, Number 190 (Tuesday, October 5, 2021)]
[Notices]
[Pages 55108-55112]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2021-21416]
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DEPARTMENT OF TRANSPORTATION
National Highway Traffic Safety Administration
[Docket No. NHTSA-2020-0104]
Denial of Motor Vehicle Defect Petition
AGENCY: National Highway Traffic Safety Administration (NHTSA),
Department of Transportation.
ACTION: Denial of petition for a defect investigation.
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SUMMARY: This notice sets forth the reasons for the denial of a
petition submitted on September 17, 2019, by Mr. Edward Chen (the
petitioner), requesting that the Agency ``initiate a Defect
Investigation into the recent set of software updates, including
software updates 2019.16.1 and 2019.16.2 and all subsequent updates
issued by Tesla, Inc. to its Model S and Model X vehicles, which have
been alleged to be issued by Tesla in response to the alarming number
of car fires that have occurred worldwide.'' On October 1, 2019, ODI
opened Defect Petition DP19-005 to evaluate the petitioner's request.
After reviewing the information provided by the petitioner, information
provided by Tesla in response to an information request letter from
NHTSA, and field data regarding non-crash vehicle fires in model year
(MY) 2012 through 2019 Tesla Model S and Model X vehicles, NHTSA has
concluded that the issues raised by the petition do not warrant a
defect investigation at this time. Accordingly, the Agency has denied
the petition.
FOR FURTHER INFORMATION CONTACT: Mr. Kareem Habib, 202-366-8703,
Vehicle Defects Division--D, Office of Defects Investigation, NHTSA,
1200 New Jersey Avenue SE, Washington, DC 20590.
SUPPLEMENTARY INFORMATION:
1.0 Introduction
Pursuant to 49 CFR 552.1, interested persons may petition NHTSA
requesting that the Agency initiate an investigation to determine
whether a motor vehicle or an item of replacement equipment fails to
comply with applicable motor vehicle safety standards or contains a
defect that relates to motor vehicle safety. Upon receipt of a properly
filed petition, the Agency conducts a technical review (49 CFR 552.6)
of the petition, material submitted with the petition, and any
appropriate additional information. After the technical review and
considering appropriate factors, which may include, among others,
Agency priorities, and the likelihood of success in litigation that
might arise from a determination of noncompliance or a defect related
to motor vehicle safety, the Agency will grant or deny the petition (49
CFR 552.8).
2.0 The Petition
In a September 17, 2019 letter, the petitioner requested that the
Agency ``initiate a Defect Investigation into the recent set of
software updates, including software updates 2019.16.1 and 2019.16.2
and all subsequent updates issued by Tesla, Inc. to its Model S and
Model X vehicles, which have been alleged to be issued by Tesla in
response to the alarming number of car fires that have occurred
worldwide.'' The petitioner's letter alleges that Tesla ``is using
over-the-air software updates to mask and cover-up a potentially
widespread and dangerous issue with the batteries in their vehicles.''
He associated the updates with a loss of range and requested that the
investigation include model year (MY) 2012 through 2019 Tesla Model S
and Model X vehicles:
``The fact pattern for most, if not all, of the affected owners is
the same and begin in or around late May 2019, where Tesla issued its
2019.16.1. and 2019.16.2 software updates. For most owners, it was
shortly discovered after updating their cars that the cars had suffered
from a sudden and significant decrease in the amount of rated miles
available. On average, affected owners have reported losing anywhere
between 25-30 miles, with 50 miles of range loss at the higher end of
the spectrum.''
``There is evidence to suggest that Tesla issued these updates in
response to an increasing number of battery fires that have occurred
worldwide. Tesla has taken the position and made statements to the
public regarding the same, that the updates were issued in order to
promote the health and longevity of their batteries. Additionally,
despite some media coverage and news outlets having covered the issue
and taking interest in the litigation, it is clear that there is
widespread confusion and uncertainty regarding the true purpose of the
software updates in question and the safety of the affected
vehicles.<SUP>1 2 3</SUP>''
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\1\ <a href="https://www.reuters.com/article/tesla-battery/tesla-hit-by-lawsuit-claiming-thousands-of-owners-lost-battery-capacity-after-software-update-idUSL2N25418A">https://www.reuters.com/article/tesla-battery/tesla-hit-by-lawsuit-claiming-thousands-of-owners-lost-battery-capacity-after-software-update-idUSL2N25418A</a>.
\2\ <a href="https://electrek.co/2019/08/08/tesla-owner-range-slashed-software-update-class-action-">https://electrek.co/2019/08/08/tesla-owner-range-slashed-software-update-class-action-</a> lawsuit/.
\3\ <a href="https://insideevs.com/news/364347/tesla-model-s-update-lawsuit/">https://insideevs.com/news/364347/tesla-model-s-update-lawsuit/</a>.
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In a class action lawsuit complaint submitted as an attachment to
the petition, the petitioner cited five non-crash fires in Tesla
vehicles summarized in Table 1.\4\
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\4\ Rasmussen v. Tesla, 5:19-cv-04596, United States District
Court for the Northern District of California, filed August 7, 2019.
[[Page 55109]]
Table 1--Fires Cited by Petitioner
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Date Vehicle Location
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June 15, 2018................... 2012 Model S 85... West Hollywood,
California.
April 21, 2019.................. 2014 Model S P85.. Shanghai, China
(Xuhui District).
May 3, 2019..................... 2014 Model S 85... San Francisco,
California.
May 12, 2019.................... 2015 Model S 85D.. Hong Kong, China.
July 30, 2019................... 2015 Model S 85D.. Ratingen, Germany.
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3.0 Analysis
On October 1, 2019, ODI opened Defect Petition DP19-005 to evaluate
the petitioner's request. On October 24, 2019, ODI sent an information
request (IR) letter to Tesla to gather information to assist the Office
in its evaluation of DP19-005. The letter included requests for
production data, over-the-air (OTA) firmware updates, non-crash fire
incidents, and Tesla's investigations related to the fires. In
evaluating the petition, ODI:
1. Analyzed the scope of the petition and the alleged defect;
2. Analyzed the non-crash fire incidents cited by the petitioner;
3. Reviewed over-the-air updates to the Battery Management System
(BMS) released by Tesla from May 2019 to date; and
4. Reviewed all relevant Vehicle Owner Questionnaires (VOQs)
received through August 2021.
3.1 Subject Vehicles
Tesla sold approximately 225,000 MY 2012 through 2019 Model S and
Model X vehicles in the United States. This petition evaluation will
focus on vehicles receiving the firmware update that could limit
maximum brick voltage.
Table 2--Petition Scope and Subject Vehicle Population
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Model
Voltage limiting firmware installed Model years -------------------------------- Total
Model S Model X
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Yes................................... 2012-2016............... 61,781 0 61,781
No.................................... 2016-2019............... 93,163 69,801 162,964
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Total............................. 2012-2019............... 154,944 69,801 224,745
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The subject firmware was installed in certain MY 2012 through 2016
Model S vehicles that were equipped with the first two generations of
the Panasonic 18650 battery cell (subject vehicles). Tesla sold
approximately 62,000 subject vehicles in the United States (Table 2).
The firmware update limiting maximum brick (defined below) voltage is a
dynamic algorithm that is enabled in vehicles with high Supercharging
use histories.<SUP>5 6</SUP> Through August 20, 2021, that firmware had
been enabled in approximately 2,062 vehicles, or about 3.5 percent of
the subject vehicles.
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\5\ When the firmware is ``enabled,'' the maximum cell voltage
is limited.
\6\ ``Supercharger'' is Tesla's name for its DC fast charging
network. The terms Supercharging and fast charging are used
interchangeably in this report.
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3.2 Subject System
The subject vehicles are equipped with high voltage (HV) battery
packs containing first- and second-generation nickel cobalt aluminum
(NCA) Panasonic 18650 form factor cells. The packs contain up to 16
modules, with each module containing 6 series elements (bricks)
comprising 74 cells connected in parallel.\7\ Each module in the
battery pack has a battery monitoring board (BMB) to monitor module
brick parameters. The battery cooling system distributes ethylene
glycol/water coolant to each module through front, left and right
manifolds. Coolant enters and exits the battery pack through
connections at the front of the pack. Each module has a single ribbon-
shaped cooling tube that snakes through the rows of battery cells,
placing the tube in contact with each cell in the module. The cooling
tubes for all modules are connected in parallel.
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\7\ The battery packs in the subject vehicles contain up to
7,104 cells.
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The BMS monitors system voltages, currents and temperatures to
control the HV battery within safe operating limits and maximize
battery capacity. The BMS receives information from sensors at the
brick and module levels, including voltage signals from each of the
BMBs and temperature signals from two sensors in each module. The BMS
controls a system of switches and resistors to manage current ``bleed''
from each brick to maintain the bricks in balance and maximize the
capacity the battery pack can provide.
The BMS in the subject vehicles has hundreds of diagnostic routines
to monitor for anomalies in the HV battery, including diagnostics for
state-of-charge (SOC) brick-to-brick imbalances.\8\ When anomalies are
detected, the BMS may initiate an internal compensation (e.g., to
balance brick voltages), trigger mitigations (e.g., range reduction or
limits on vehicle restart or charging), or trigger warnings, such as,
``Car needs service; Contact Tesla Service'' or, for the most serious
conditions, ``Car shutting down; PULL OVER IMMEDIATELY.''
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\8\ These diagnostics were part of the BMS prior to the release
of the subject firmware updates that are the focus of this defect
petition and have continued to be updated through Tesla's standard
practices in the months since the subject updates (see Section 3.5
``Tesla Updates'').
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At the cell level, the subject vehicles contain design features
that may disable the cells in response to certain short conditions,
including separator shutdown, Current Interrupt Device (CID)
activation, and cell interconnect fusing. Should single cell runaway
occur, the subject battery packs are designed to prevent propagation to
surrounding cells (Passive Propagation Resistance) by releasing the hot
gasses through the top of the initiating cell and venting them away
from the module.
3.3 China Fires
On April 21, 2019, a 2014 Model S experienced a battery fire in a
parking garage in the Xuhui District of Shanghai, China, shortly after
recharging the HV battery. Tesla's investigation of the fire identified
several factors in common
[[Page 55110]]
with other non-crash battery fires in China, including a fire in a 2015
Model S in Hong Kong, referenced by the petitioner, that occurred three
weeks later. First, each of the fires occurred shortly after completing
a Supercharging session to a high SOC. Second, the fires occurred when
the vehicles were parked with the cooling systems off and the HV
batteries remaining at high SOCs. Third, the vehicle histories showed
high percentages of fast charging, average depth of discharge (DoD),
and other stress factors for the HV battery packs (e.g., ``top off''
charging \9\ above 90 percent SOC).\10\ Lastly, the vehicles were
equipped with battery packs using first or second-generation battery
cells. Reviews of the Shanghai-Xuhui and Hong Kong fire investigations
are provided in the following summaries:
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\9\ ``Top off'' charging refers to the practice of re-initiating
charging from a very high SOC after the system has completed the
initial charge.
\10\ Tesla also noted other unique factors in the China non-
crash fires, including a broken AC compressor in one vehicle and a
remanufactured battery pack with a recent fault detection in
another.
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Shanghai-Xuhui Fire. On April 21, 2019, a 2014 Tesla Model S P85
caught fire in a parking garage approximately 75 minutes after
completing a Supercharging session to 96 percent SOC.\11\ The vehicle
had a high percentage of fast charging use (78 percent). Tesla's
investigation, conducted in conjunction with China's safety regulators,
did not find a root cause. However, the company believed the fire
likely resulted from a combination of factors, including charging
history and thermal conditions following a Supercharging session.
Battery charging histories that include high stress conditions such as
Supercharging increase the likelihood of developing internal cell
failures that can lead to ``weak short'' conditions.\12\ Thermal
conditions following the Supercharging session may create conditions in
which a single cell failure may propagate to neighboring cells,
resulting in thermal runaway of the affected module.
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\11\ Tesla provided ODI with a technical review of its
investigation of the China fires on June 12, 2019.
\12\ Frequent fast charging, high SOC, large swings in SOC
(e.g., going from a high depth of discharge to a high SOC), specific
patterns of rest intervals at low SOCs, and ``top-off'' charging all
result in high stress to the HV battery.
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Hong Kong Fire. On May 12, 2019, a 2015 Tesla Model S 85D caught
fire in a parking garage approximately 74 minutes after completing a
Supercharging session to 96 percent SOC. The vehicle's charging history
was almost exclusively fast charging (94 percent). The vehicle had
previously been repaired as part of a unique process in China and Hong
Kong in which a vehicle's battery pack is removed, remanufactured and
reinstalled.\13\ The vehicle had triggered a warning ``car needs
service'' and a voltage fault was confirmed at a Tesla service center.
However, the issue was not considered urgent and the repair was
scheduled for the week after the fire occurred. The incident vehicles'
battery charging history and recent Supercharging session increase the
likelihood that it may have shared characteristics with the Shanghai-
Xuhui fire.
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\13\ This process is not used in the United States.
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3.4 Other Non-Crash Vehicle Fires Cited by Petitioner
Apart from the incidents in China, Tesla stated that it is not
aware of any non-crash HV battery fires associated with fast charging
in the United States or any other country. The three incidents cited by
the petitioner that did not occur in China include one HV battery fire
that was not related to fast charging and two that were external to the
HV battery. Reviews of the investigations of each of those incidents
and a fourth non-crash fire incident that occurred in December 2018
\14\ are provided in the following summaries:
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\14\ <a href="https://electrek.co/2018/12/19/tesla-model-s-fire-towing/">https://electrek.co/2018/12/19/tesla-model-s-fire-towing/</a>.
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West Hollywood Fire. On June 15, 2018, a 2012 Tesla Model S 85
experienced thermal runaway in Module 14 while driving on Santa Monica
Boulevard in West Hollywood, California.\15\ Unlike the China fire
incidents reviewed by ODI, there was no fast charging event prior to
this fire, the vehicle was driving with the cooling system in operation
when the fire occurred, and the vehicle had no fast charging in its
service history.\16\ Tesla's investigation evaluated multiple potential
causal factors in the affected module, but was unable to determine a
root cause. Tesla has advised the Agency that it has not seen another
similar fire. Because there was no fast charging prior to the incident
and no history of fast charging, this incident is not believed to be
related to the 2019 fires investigated in China.
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\15\ Tesla provided ODI with a technical review of its
investigation of the West Hollywood fire on September 6, 2018.
\16\ The vehicle had completed a slow AC charge at the owner's
residence earlier in the day and then driven to a SOC of less than
89 percent at the time of the fire incident.
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Los Gatos Fire. On December 18, 2018, a 2018 Tesla Model S
experienced runaway in Modules 13-16 after being towed to a tire repair
shop in Los Gatos, California.\17\ The vehicle was not at a high SOC
when the incident occurred and the vehicle had a low frequency of fast
charging in its history (13 percent). In addition, the incident vehicle
was equipped with a battery pack using later generation cells, putting
it outside the scope of the subject vehicles for this petition
evaluation. Tesla's investigation was unable to identify a root cause,
but could not rule out physical damage. This incident is not relevant
to this petition because it used different cells than what is at issue
in this petition.
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\17\ Tesla provided ODI with a technical review of its
investigation of the Los Gatos fire on June 12, 2019.
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San Francisco Fire. On May 3, 2019, a 2014 Tesla Model S 85 caught
fire while parked in a residential garage.\18\ Tesla's investigation
determined the that the fire originated in the rear drive unit. The
fire did not originate in the HV battery and is not relevant to this
petition.
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\18\ Tesla provided ODI with a technical review of its
investigation of the San Francisco fire on June 12, 2019.
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Ratingen, Germany Fire. On July 30, 2019, a 2015 Tesla Model S 85D
caught fire in Ratingen, Germany while parked in a parking lot. The
vehicle was at a low SOC (approximately 40 percent) and had been parked
for at least 14 hours when the fire occurred. The cause of the fire is
undetermined, but Tesla has determined that the origin of the fire was
external to the HV battery pack.
3.5 Tesla Updates
As background, Tesla provides regular OTA updates to add new
features or enhance existing functions to systems throughout the
vehicle, including updates to optimize charging rate, charging
capacity, and thermal management of the HV battery.\19\ The updates are
numbered by the year and week of release and wave.\20\
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\19\ <a href="https://www.tesla.com/support/software-updates">https://www.tesla.com/support/software-updates</a>.
\20\ The Safety Act imposes an obligation on manufacturers of
motor vehicles and motor vehicle equipment to notify NHTSA when they
determine vehicles or equipment they produced contain defects
related to motor vehicle safety or do not comply with an applicable
motor vehicle safety standard. See 49 U.S.C. 30118. This notice,
referred to as a Safety Recall Report, must be filed no more than
five working days after the manufacturer knew or should have known
of the defect or noncompliance. See 49 CFR 573.6(b); see also United
States v. General Motors Corp., 656 F. Supp. 1555, 1559 n.5 (D.D.C.
1987). NHTSA recognizes that over-the-air updates are issued for a
variety of reasons including to offer new product features, fix
software bugs, and to optimize vehicle performance. NHTSA, however,
expects any manufacturer issuing an over-the-air update that
mitigates a defect that poses an unreasonable risk to motor vehicle
safety to file an accompanying Safety Recall Report pursuant to 49
CFR part 573.
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[[Page 55111]]
In May 2019, while continuing its investigation of the Shanghai-
Xuhui fire, Tesla issued OTA firmware updates 2019.16.x revising fast
charging and thermal management strategies at high SOCs for all Model S
vehicles. Tesla has indicated that these changes were implemented as
improvements to battery health, longevity and safety. In addition, OTA
2019.16.1, released May 15, 2019, included a dynamic algorithm that
enables a limit on maximum brick voltage if the vehicle has a high
ratio of DC fast charging in its history. This update was limited to
vehicles equipped with first and second-generation battery cells. Tesla
stated that the cell voltage limit was implemented as a precaution
while Tesla continued to investigate the causes of the fires in China.
A subsequent update, released in August 2019, restored some of the
voltage capacity to affected vehicles.\21\
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\21\ OTA 2019.28.x.
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Staggered updates, released to targeted sub-populations of subject
vehicles in November 2019 and December 2019, activated a new ``weak
short'' detection algorithm designed to identify shorts months before
they could potentially result in cell runaway. Vehicles in which the
voltage limiting firmware had been enabled have received further
incremental restoration of maximum-allowed brick voltage after
receiving the ``weak short'' detection update.
3.6 VOQ Analysis
Through August 2021, ODI identified 67 complaints from consumers
alleging reductions in battery capacity or charging speed in Model S
and Model X vehicles, all but 4 of which were received after DP19-005
was opened.\22\ Six of the complaints involved Model S or Model X
vehicles that are not in the scope of the subject vehicles (i.e.,
vehicles equipped with battery packs using later generation battery
cells that were not affected by the firmware update with the algorithm
that could limit maximum brick voltage). Of the 59 complaints involving
subject vehicles through December 2020, 52 alleged reductions in
battery capacity and driving range after receiving the subject OTA
updates and 7 alleged reduced DC fast charging speeds.
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\22\ The three complaints received before DP19-005 was opened
were submitted by the petitioner or his client (see NHTSA complaint
ID's 11240787, 11246770 and 11246771).
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Data provided by Tesla indicate that the maximum brick voltage
firmware had been enabled in 30 of the 52 vehicles alleging reduced
charging capacity. Of those vehicles, by the end of August 2021, Three
had received a new battery under warranty, 26 had received full
restoration of maximum brick voltage, and 4 continued to have maximum
brick voltage limited at approximately 93 percent.\23\ None of the
vehicles have reported any thermal incidents or other safety hazards
related to the HV battery.
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\23\ No data was available for two vehicles due to a lack of
recent communication with Tesla's remote diagnostics.
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4.0 Manufacturer Position
Tesla's investigation of the non-crash fires in China did not
identify a root cause or positively link the incidents to any design or
manufacturing defect conditions.\24\ The company identified a potential
concern with internal cell shorts that may occur within a narrow range
of resistance values that were below BMS diagnostic thresholds. Tesla
stated that while such shorts occur very rarely, they can be caused by
multiple factors and high-stress use can contribute to their formation
and growth. Internal cell shorts usually result in cell failure without
leading to a thermal incident, but can progress to cell runaway.
According to Tesla, under certain thermal conditions most likely to
occur shortly after completion of a Supercharging session, cell runaway
may overcome the passive propagation of the system and lead to module
runaway. Tesla indicated that the latter has only been observed in
China.
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\24\ Tesla's investigation included forensic analysis of battery
packs from incident vehicles and reviews of cell manufacturing
process issues that may affect intercalation kinetics during fast
charging.
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Tesla released several OTA firmware updates to improve the thermal
management, fast charging strategy, and BMS diagnostics to detect early
signs of internal cell shorts. Per the company, the updates will
improve the durability and health of batteries subjected to high-stress
use conditions, as well as providing an added margin of safety.
5.0 Observations
ODI's analysis of the petition allegations, information provided by
Tesla, and information contained in consumer complaints finds the
following:
<bullet> The voltage limiting firmware that is the focus of the
petition was installed in just 27 percent of the vehicles cited by the
petitioner and enabled in less than 1 percent.
<bullet> The subject OTA firmware is a dynamic algorithm that may
limit maximum brick voltage based on battery usage stress. The voltage
limit is based on fast charging history. Frequent fast charging is
recognized as a stress factor that can adversely affect battery health,
longevity, durability, lithium plating aging conditions and overall
safety of lithium-ion batteries.\25\
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\25\ A. Tomaszewska, Z. Chu, X. Feng, S. O'Kane, X. Liu, J.
Chen, et al. (2019). Lithium-Ion Battery Fast Charging: A Review.
eTransportation. 100011. 10.1016/j.etran.2019.100011.
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<bullet> Approximately 80 percent of the vehicles in which the
firmware limiting maximum brick voltage was enabled have had the
maximum voltage restored by August 2021 and almost all the remaining
vehicle population had the maximum voltage partially restored to 93
percent or higher.
<bullet> A small number of vehicles have received new battery packs
after receiving alerts triggered by the new ``weak short'' detection
algorithm.\26\
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\26\ The weak short alert algorithm is independent of charging
history. HV battery pack replacements have occurred in vehicles with
the brick voltage limiting firmware enabled and in vehicles where it
had not been enabled. The likelihood of receiving an alert was
higher in the vehicles with the maximum brick voltage firmware
enabled.
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<bullet> There are many potential causes of non-crash battery fires
in vehicles equipped with lithium ion batteries.<SUP>27 28</SUP> ODI
looks for indications of a common cause or pattern of incidents when
assessing evidence of a potential defect that may warrant
investigation. While a pattern of fires occurring shortly after
completing Supercharging sessions was observed in China, no similar
fire incidents have been identified in the United States.
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\27\ Brewer, J., Nasser, A., Hommes, Q.V.E., Najm, W., Pollard,
J., & Jackson, C. (2018, November). Safety management of automotive
rechargeable energy storage systems: The application of functional
safety principles to generic rechargeable energy storage systems
(Report No. DOT HS 812 556). Washington, DC: National Highway
Traffic Safety Administration.
\28\ Stephens, D., Shawcross, P., Stout, G., Sullivan, E.,
Saunders, J., Risser, S., & Sayre, J. (2017, October). Lithium-ion
battery safety issues for electric and plug-in hybrid vehicles
(Report No. DOT HS 812 418). Washington, DC: National Highway
Traffic Safety Administration.
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<bullet> The available data indicate that non-crash battery fires
in Tesla vehicles are rare events. The fires occurring in vehicles
parked at high SOCs shortly after completing Supercharging sessions
have only been observed in China. High stress use factors appear to be
more common in China. For example, the population of subject vehicles
in China is approximately 6 percent that of the United States, but
China has 51 percent more vehicles with fast charging histories of 80
percent or greater.
<bullet> The three fires cited by the petitioner that occurred
outside China include two that did not originate in the battery (San
Francisco and Ratingen) and a third that is unrelated to a fast
charging event.
<bullet> No fires related to the subject condition have been
observed globally
[[Page 55112]]
since three fires in China and Hong Kong over a 48-day period from
late-March to mid-May 2019.
<bullet> There have been no fires in the United States related to
the subject condition.
<bullet> ODI will continue to monitor the battery performance of
the subject vehicles.
6.0 Conclusion
NHTSA is authorized to issue an order requiring notification and
remedy of a defect if the Agency's investigation shows a defect in the
design, construction, or performance of a motor vehicle that presents
an unreasonable risk to safety. 49 U.S.C. 30102(a)(9), 30118. Given the
absence of any incidents in the United States related to fast charging,
and the absence of any such incidents globally since May 2019, it is
unlikely that an order concerning the notification and remedy of a
safety-related defect would be issued due to any investigation opened
as a result of granting this petition. Therefore, upon full
consideration of the information presented in the petition, and the
potential risks to safety, the petition is denied. The denial of this
petition does not foreclose the Agency from taking further action if
warranted, or the potential for a future finding that a safety-related
defect exists based upon additional information the Agency may receive.
Authority: 49 U.S.C. 30162(d); delegations of authority at CFR 1.95
and 501.8.
Joseph Kolly,
Acting Associate Administrator for Enforcement.
[FR Doc. 2021-21416 Filed 10-4-21; 8:45 am]
BILLING CODE 4910-59-P
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This is legal information, not legal advice. Laws vary by jurisdiction and change frequently. Always verify current law with official sources and consult a licensed attorney in your jurisdiction for advice on your specific situation.