Document ID: NHTSA-2020-0104-0003
Agency: nhtsa
Document Type: Notice
Title: Denial of Motor Vehicle Defect Petition
Posted Date: 2021-10-05T04:00Z

[Federal Register Volume 86, Number 190 (Tuesday, October 5, 2021)]
[Notices]
[Pages 55108-55112]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[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.1 2 3''
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    \1\ https://www.reuters.com/article/tesla-battery/tesla-hit-by-lawsuit-claiming-thousands-of-owners-lost-battery-capacity-after-software-update-idUSL2N25418A.
    \2\ https://electrek.co/2019/08/08/tesla-owner-range-slashed-software-update-class-action- lawsuit/.
    \3\ https://insideevs.com/news/364347/tesla-model-s-update-lawsuit/.
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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.5 6 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\ https://electrek.co/2018/12/19/tesla-model-s-fire-towing/.
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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\ https://www.tesla.com/support/software-updates.
    \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:
     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.
     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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     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.
     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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     There are many potential causes of non-crash battery fires 
in vehicles equipped with lithium ion batteries.27 28 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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     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.
     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.
     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.
     There have been no fires in the United States related to 
the subject condition.
     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