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GB/T 38661-2020 (GB/T38661-2020, GBT 38661-2020, GBT38661-2020)
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GB/T 38661-2020: PDF in English (GBT 38661-2020)

GB/T 38661-2020
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 43.080
T 47
Technical Specifications of Battery Management
System for Electric Vehicles
ISSUED ON: MARCH 31, 2020
IMPLEMENTED ON: OCTOBER 1, 2020
Issued by: State Administration for Market Regulation;
Standardization Administration of the People’s Republic of
China.
Table of Contents
Foreword ... 3 
1 Scope ... 4 
2 Normative References ... 4 
3 Terms and Definitions ... 5 
4 Abbreviations and Symbols ... 6 
5 Technical Requirements ... 7 
6 Test Methods ... 15 
7 Inspection Rules ... 22 
Appendix A (normative) System Functional Status Level ... 26 
Appendix B (normative) Test Method for SOC Accumulative Error ... 27 
Appendix C (informative) SOC Error Correction Speed Test ... 30 
Appendix D (informative) SOP Estimation Error Test Method ... 37 
Appendix E (informative) Equilibrium Test Method ... 40 
Appendix F (informative) Typical Charging and Discharging Working Conditions
of Battery System ... 42 
Technical Specifications of Battery Management
System for Electric Vehicles
1 Scope
This Standard specifies the technical requirements, test methods and inspection rules
of power storage battery management system for electric vehicles (hereinafter referred
to as battery management system).
This Standard is applicable to li-ion power battery and nickel-hydrogen power battery
management system for electric vehicles. The management system of other types of
power storage battery may take this as a reference.
2 Normative References
The following documents are indispensable to the application of this document. In
terms of references with a specified date, only versions with a specified date are
applicable to this document. In terms of references without a specified date, the latest
version (including all the modifications) is applicable to this document.
GB/T 4365 Electrotechnical Terminology - Electromagnetic Compatibility
GB/T 17626.4-2018 Electromagnetic Compatibility - Testing and Measurement
Techniques - Electrical Fast Transient / Burst Immunity Test
GB/T 18384.3-2015 Electrically Propelled Road Vehicles - Safety Specifications - Part
3: Protection of Persons against Electric Shock
GB/T 18655-2018 Vehicles, Boats, and Internal Combustion Engines - Radio
Disturbance Characteristics - Limits and Methods of Measurement for the Protection
of On-board Receivers
GB/T 19596-2017 Terminology of Electric Vehicles
GB/T 19951 Road Vehicles - Disturbances Test Methods for Electrical / Electronic
Component from Electrostatic Discharge
GB/T 21437.2-2008 Road Vehicles - Electrical Disturbances from Conduction and
Coupling - Part 2: Electrical Transient Conduction along Supply Lines Only
GB/T 21437.3-2012 Road Vehicles - Electrical Disturbances from Conduction and
Coupling - Part 3: Electrical Transient Transmission by Capacitive and Inductive
Coupling via Lines other than Supply Lines
GB/T 27930 Communication Protocols between Off-board Conductive Charger and
Battery Management System for Electric Vehicle
GB/T 28046.1-2011 Road Vehicles - Environmental Conditions and Testing for
Electrical and Electronic Equipment - Part 1: General
GB/T 28046.2-2011 Road Vehicles - Environmental Conditions and Testing for
Electrical and Electronic Equipment - Part 2: Electrical Loads
GB/T 28046.3-2011 Road Vehicles - Environmental Conditions and Testing for
Electrical and Electronic Equipment - Part 3: Mechanical Loads
GB/T 28046.4-2011 Road Vehicles - Environmental Conditions and Testing for
Electrical and Electronic Equipment - Part 4: Climatic Loads
GB/T 33014.2 Road Vehicles - Component Test Methods for Electrical / Electronic
Disturbances from Narrowband Radiated Electromagnetic Energy - Part 2: Absorber-
lined Shielded Enclosure
GB/T 33014.4 Road Vehicles - Component Test Methods for Electrical / Electronic
Disturbances from Narrowband Radiated Electromagnetic Energy - Part 4: Bulk
Current Injection (BCI)
ISO 11452-8:2015 Road Vehicles - Component Test Methods for Electrical
Disturbances from Narrowband Radiated Electromagnetic Energy - Part 8: Immunity
to Magnetic Fields
3 Terms and Definitions
What is defined in GB/T 4365, GB/T 19596-2017 and GB/T 28046.1-2011, and the
following terms and definitions are applicable to this document. For ease of use, some
terms and definitions in GB/T 19596-2017 are repeatedly listed out.
3.1 Battery Electronics
Battery electronics refers to an electronic device that collects or simultaneously
monitors electrical and thermal data of secondary cells or modules. If necessary, it may
include electronic components used for secondary cell equilibrium.
NOTE: battery electronics may include secondary cell controller; the equilibrium between
secondary cells may be controlled by battery electronics, or, through battery
control unit.
[GB/T 19596-2017, Definition 3.3.2.1.5]
3.2 Battery Control Unit
BCU: Battery Control Unit
BMS: Battery Management System
FS: Full Scale
NOTE: FS refers to the absolute value of the maximum measurable value of the battery
management system.
SOC: State of Charge
SOP: State of Power
4.2 Symbols
The following symbols are applicable to this document.
C1: 1 h rated capacity (Ah).
I1: 1 h discharging current (A), whose value equals to the rated capacity.
5 Technical Requirements
5.1 Service Environment
5.1.1 Operating Temperature
-20 °C ~ 65 °C, or, negotiated and determined by OEMs and manufacturers in
accordance with the stipulations of GB/T 28046.4-2011, and the installation location of
the battery management system.
5.1.2 Storage temperature
-40 °C ~ 85 °C, or, negotiated and determined by OEMs and manufacturers in
accordance with the stipulations of GB/T 28046.4-2011, and the installation location of
the battery management system.
5.1.3 Operating humidity
5% ~ 95%, or, negotiated and determined by OEMs and manufacturers in accordance
with the stipulations of GB/T 28046.4-2011, and the installation location of the battery
management system.
5.2 Supply Voltage
The range of supply voltage is shown in Table 1, or, negotiated and determined by
OEMs and manufacturers.
should have SOP estimation and equilibrium function.
5.4 State Parameter Measurement Accuracy
5.4.1 Total voltage
The detection accuracy of total voltage shall satisfy ± 1% FS.
5.4.2 Total current
5.4.2.1 In terms of li-ion power battery, the detection accuracy of total current shall
satisfy ± 2% FS.
5.4.2.2 In terms of nickel-hydrogen power battery, the detection accuracy of total
current shall satisfy ± 3% FS.
5.4.3 Secondary cell (cell group) voltage
5.4.3.1 In terms of li-ion power battery, the detection accuracy of secondary cell (cell
group) voltage shall satisfy ± 0.5% FS; the absolute value of the maximum error shall
be not more than 10 mV.
5.4.3.2 In terms of nickel-hydrogen power battery, the detection accuracy of secondary
cell (cell group) voltage or module voltage shall satisfy ± 1% FS.
5.4.4 Temperature
5.4.4.1 In terms of li-ion power battery, within the range of -20 °C ~ 65 °C (including -
20 °C and 65 °C), the temperature detection accuracy shall satisfy ± 2 °C; within the
range of -40 °C ~ -20 °C and 65 °C ~ 125 °C (or the highest measured temperature
calibrated by the battery management system), the temperature detection accuracy
shall satisfy ± 3 °C.
5.4.4.2 In terms of nickel-hydrogen power battery, within the range of -20 °C ~ 65 °C
(including -20 °C and 65 °C), the temperature detection accuracy shall satisfy ± 3 °C;
within the range of -40 °C ~ -20 °C and 65 °C ~ 125 °C (or the highest measured
temperature calibrated by the battery management system), the temperature detection
accuracy shall satisfy ± 5 °C.
5.4.5 Insulation resistance
In terms of battery management system equipped with the insulation resistance value
detection function, when the total battery voltage (nominal) is above 400 V (including
400 V), the relative error of insulation resistance detection shall be -20 % ~ +20%;
when the total battery voltage (nominal) is below 400 V, the relative error of insulation
resistance detection shall be -30% ~ +30%.
When the insulation resistance is less than, or equals to 50 k, the detection accuracy
The battery management system shall be tested in accordance with 6.6.1. The
functional status shall reach Level-A specified in Appendix A.
5.8.2 Overvoltage
The battery management system shall be tested in accordance with 6.6.2. The
functional status shall reach Level-C specified in Appendix A.
5.8.3 Superimposed AC voltage
The battery management system shall be tested in accordance with 6.6.3. When the
nominal voltage is 12 V, the system test severity level is 2. When the nominal voltage
is 24 V, the system test severity level is 3. The functional status shall reach Level-A
specified in Appendix A.
5.8.4 Slow drop and rise of supply voltage
The battery management system shall be tested in accordance with 6.6.4. Within the
range of the supply voltage, the functional status shall reach Level-A as specified in
Appendix A. Beyond the range of the supply voltage, the functional status shall at least
reach Level-C specified in Appendix A.
5.8.5 Transient changes of supply voltage
The battery management system shall be tested in accordance with 6.6.5. The
functional status shall reach Level-C specified in Appendix A.
5.8.6 Reverse voltage
The battery management system shall be tested in accordance with 6.6.6. The
functional status shall reach Level-C specified in Appendix A.
5.8.7 Short-circuit protection
The battery management system shall be tested in accordance with 6.6.7. The
functional status shall reach Level-C specified in Appendix A.
5.9 Environmental Adaptability
5.9.1 Sinusoidal vibration
The battery management system shall be able to endure the vibration test specified in
6.7.1. After the test, it shall be able to normally function and satisfy the requirements
for state parameter measurement accuracy in 5.4. In addition, it shall pass visual
inspection and there shall be no falling-off of components and parts.
5.9.2 Random vibration
The battery management system shall receive the salt mist resistance test in
accordance with 6.7.8; no saltwater is allowed to enter the housing. Under the
operating mode specified in GB/T 28046.1-2011 in 3.2, the functional status shall reach
Level-A specified in Appendix A. For test objects completely placed in the passenger
compartment, luggage compartment or cargo compartment, the salt mist resistance
test is not required. For test objects installed inside the battery compartment, if the
compartment’s protection level reaches IP 67, the salt mist resistance test may not be
performed.
5.9.9 Damp heat cycle
The battery management system shall receive the damp heat cycle test in accordance
with 6.7.9. The functional status shall reach Level-A specified in Appendix A.
5.10 Electromagnetic Compatibility Performance
5.10.1 Conduction disturbance
The battery management system shall be tested in accordance with 6.8.2. If OEMs
and the manufacturers do not have special stipulations, the limit value of conduction
disturbance shall comply with the requirements of Level-3 specified in GB/T 18655-
2018.
5.10.2 Radiation disturbance
The battery management system shall be tested in accordance with 6.8.3. If OEMs
and the manufacturers do not have special stipulations, the limit value of radiation
disturbance shall comply with the requirements of Level-3 specified in GB/T 18655-
2018.
5.10.3 Transient conduction immunity of power line
The battery management system shall be tested in accordance with 6.8.4. If OEMs
and the manufacturers do not have special stipulations, the requirements for functional
status in the test result are shown in Table 4.
Table 4 -- Requirements for Transient Conduction Immunity of Power Line of
Battery Management System
5.10.4 Transient conduction immunity of signal line / control line
The battery management system shall be tested in accordance with 6.8.5. If OEMs
Test Pulse
System’s
Functional Status
6.2.4.1 In terms of li-ion battery, at -20 °C ± 2 °C, 25 °C ± 2 °C and 65 °C ± 2 °C (or, it
may be determined by OEMs and the manufacturers through negotiation in
accordance with the practical application), respectively detect 1.5 V, 3 V and 4.5 V
secondary cell voltage (the number of channels is not less than the number of sampling
units of one independent power supply). Compare the data collected by the battery
management system with the data monitored by the detection equipment.
6.2.4.2 In terms of nickel-metal hydride battery, at -20 °C ± 2 °C, 25 °C ± 2 °C and
65 °C ± 2 °C (or, it may be determined by OEMs and the manufacturers through
negotiation in accordance with the practical application), respectively detect module
voltage n  1.0 V, n  1.2 V, n  1.6 V (n is the number of secondary cells connected
in series in the module, where the number of channels is not less than the number of
sampling units of one independent power supply). Compare the data collected by the
battery management system with the data monitored by the detection equipment.
6.2.5 Temperature
At -20 °C ± 2 °C, 25 °C ± 2 °C and 65 °C ± 2 °C (or, it may be determined by OEMs
and the manufacturers through negotiation in accordance with the practical application),
simultaneously place the probe of the temperature measurement device of the battery
management system and the probe of the sensor of the detection equipment at -40 °C,
0 °C, 25 °C, 40 °C and 125 °C (or the highest measured temperature calibrated by the
battery management system); measure the temperature value. Compare the data
collected by the battery management system with the data monitored by the detection
equipment.
6.2.6 Insulation resistance
Under 50%, 75% and 100% full-scale voltage, respectively connect the total positive
to ground and the total negative to ground of the battery to the insulation resistance
array. In accordance with 80 /V, 100 /V, 300 /V, 500 /V and 2 /V, respectively
control the insulation resistance array to different resistance values. Compare the data
collected by the battery management system with the actual resistance value of the
insulation resistance array.
6.3 SOC Estimation Accuracy
In this Standard, SOC estimation accuracy test includes SOC accumulative error test
and SOC error correction speed test. SOC accumulative error test shall be conducted
in accordance with Appendix B. SOC error correction speed test may be conducted in
accordance with Appendix C. SOC estimation error test caused by battery aging or
other factors shall be negotiated by OEMs and the manufacturers.
6.4 Battery Fault Diagnosis
Through the simulation system, establish triggering conditions that satisfy the fault
Or, DC test voltage may also be applied; the equivalent DC test voltage is 1.41 times
of the AC voltage value.
6.6 Electrical Adaptability
6.6.1 DC supply voltage
In accordance with the stipulations of 4.2 in GB/T 28046.2-2011, conduct DC supply
voltage test.
6.6.2 Overvoltage
In accordance with the stipulations of 4.3 in GB/T 28046.2-2011, conduct overvoltage
test.
6.6.3 Superimposed AC voltage
In accordance with the stipulations of 4.4 in GB/T 28046.2-2011, conduct
superimposed AC voltage test.
6.6.4 Slow drop and rise of supply voltage
In accordance with the stipulations of 4.5 in GB/T 28046.2-2011, conduct supply
voltage slow drop and rise test.
6.6.5 Transient changes of supply voltage
In accordance with the stipulations of 4.6 in GB/T 28046.2-2011, conduct supply
voltage transient change test.
6.6.6 Reverse voltage
In accordance with the stipulations of 4.7 in GB/T 28046.2-2011, conduct reverse
voltage test.
6.6.7 Short-circuit protection
In accordance with the stipulations of 4.10.2 in GB/T 28046.2-2011, conduct short-
circuit protection test.
6.7 Environmental Adaptability
6.7.1 Sinusoidal vibration
In accordance with the stipulations of GB/T 28046.3-2011, conduct sinusoidal vibration
test. The test method and test level shall be determined by OEMs and the
manufacturers in accordance with the installation location of the battery management
system through negotiation.
resistance test. In accordance with the requirements of Table 4 and Appendix A in GB/T
28046.4-2011, and the installation location, determine whether salt mist resistance test
shall be conducted.
6.7.9 Damp heat cycle
In accordance with the requirements of Table 4 and Appendix A in GB/T 28046.4-2011,
and the installation location, determine whether damp heat cycle test shall be
conducted in accordance with the stipulations of 5.6.2.2 in GB/T 28046.4-2011; the
maximum temperature is 65 °C; cycle for 5 times.
6.8 Electromagnetic Compatibility
6.8.1 General rules
6.8.1.1 The battery shall be provided by the manufacturer of the battery management
system; constitute a basic test unit together with the battery management system to
simulate the actual installation for tests.
6.8.1.2 During the test process, record the data collected by the battery management
system (the number of secondary cell or cell group voltage acquisition channels is not
less than the number of sampling units of one independent power supply; the number
of temperature acquisition channels is not less than 2). Compare it with the
corresponding data detected by the detection equipment.
6.8.1.3 Isolation devices shall be used to isolate auxiliary equipment (such as: upper
computer and monitoring software).
6.8.1.4 Charging and discharging current shall be not less than 2% of the full scale of
current measurement of the battery management system.
6.8.2 Conduction disturbance
In accordance with the test method in GB/T 18655-2018, and specific test object, select
the voltage method and the current probe method to conduct conduction disturbance
test.
6.8.3 Radiation disturbance
In accordance with the test method in GB/T 18655-2018, conduct radiation disturbance
test.
6.8.4 Transient conduction immunity of power line
In accordance with the test method in GB/T 21437.2-2008, conduct transient
conduction immunity test of power line. The test severity shall be Level-III.
6.8.5 Transient conduction immunity of signal line / control line
Appendix B
(normative)
Test Method for SOC Accumulative Error
B.1 General
B.1.1 In accordance with the requirements of normal operation, assemble the battery
system to be tested (the smallest battery system suitable for the battery management
system may be selected), or, adopt the battery simulation system.
B.1.2 At three temperature points: -20 °C ± 2 °C, 25 °C ± 2 °C, 65 °C ± 2 °C,
respectively conduct the test. During the test, place the battery management system
and its accessories related to ampere-hour integration under the selected test
environment and temperature conditions; the battery pack may be placed at room
temperature through the negotiation by OEMs and the manufacturers. Firstly, the
battery system shall carry out the test content specified in B.2, then, the test content
specified in B.3.
B.1.3 In addition to the environmental adaptation process, when it is placed still during
the test, in accordance with the manufacturer’s technical specifications, it can be
determined whether the battery management is in the operating state.
B.1.4 When the battery system is tested at a low temperature or other situations where
the conditions are not met, the charging and discharging rate may be appropriately
reduced. However, at the same time, the charging and discharging time needs to be
adjusted, so as to ensure smooth progress of the test.
B.1.5 When the target ambient temperature of the test changes, before the test, the
battery system needs to complete the environmental adaptation process: the battery
management system and accessories of the test object must be placed still for at least
1 h in the new test environment; the battery pack must be placed still in the new test
environment, till the difference between the surface temperature of the secondary cell
in the battery pack and the ambient temperature is less than 2 °C, then, it can be
considered that the environmental adaptation process of the battery system is
completed. During the process, the battery management system shall be in a non-
working state.
B.1.6 If the calculation mode of SOC submitted value is different from the actual
definition of SOC, before the test, the manufacturer shall explain the mapping
relationship.
B.1.7 The differential content of the test conditions must be stated in the test report.
B.2 Available Capacity Test
Appendix C
(informative)
SOC Error Correction Speed Test
C.1 General
C.1.1 In accordance with the requirements of normal operation, assemble the battery
system to be tested (the smallest battery system suitable for the battery management
system may be selected).
C.1.2 Within the range of -20 °C ~ 65 °C, OEMs and the manufacturers shall, in
accordance with the practical application, select at least three temperature points and
respectively conduct the test. In principle, low temperature (≤ 15 °C), normal
temperature (25 °C ± 5 °C) and high temperature (≥ 35 °C) need to be included.
C.1.3 In addition to the environmental adaptation process, when it is placed still during
the test, in accordance with the manufacturer’s technical specifications, it can be
determined whether the battery management is in the operating state.
C.1.4 When the battery system is tested at a low temperature or other situations where
the conditions are not met, the charging and discharging rate may be appropriately
reduced. However, at the same time, the charging and discharging time needs to be
adjusted, so as to ensure smooth progress of the test.
C.1.5 When the target ambient temperature of the test changes, before the test, the
battery system needs to complete the environmental adaptation process: the battery
management system and accessories of the test object must be placed still for at least
1 h in the new test environment; the battery pack must be placed still in the new test
environment, till the difference between the surface temperature of the secondary cell
in the battery pack and the ambient temperature is less than 2 °C, then, it can be
considered that the environmental adaptation process of the battery system is
completed. During the process, the battery management system shall be in a non-
working state.
C.1.6 When calculating SOCtrue value (SOCtrue value), Q0 is obtained through the available
capacity test in B.2. If the calculation mode of SOC submitted value is different from
the actual definition of SOC, before the test, the manufacturer shall explain the
mapping relationship.
C.1.7 The manufacturer may, in accordance with the differences in the type of vehicle
used in the battery system, the rate of charging and discharging capacity of the battery
and the temperature of the test environment, select the charging and discharging
working conditions in Appendix F, or negotiated and determined by OEMs for tests. In
charging and discharging capacity Q1 (charging is negative; discharging is
positive) of the test equipment; real-time SOC true value shall be calculated
by ;
n) During the full test process, calculate SOC error. The formula for the
calculation of SOC error is .
C.2.2 30% < SOC < 80%
C.2.2.1 In accordance with the following steps, test the error correction speed and
accuracy of upper biased estimated value when SOC is close to 80%:
a) In accordance with the charging specifications adopted in B.2, charge the
battery system;
b) Place it still for 30 min, or the shelving time specified by the manufacturer;
c) The test equipment begins to accumulate cyclic charging and discharging
capacity;
d) With 1 Q0 (A), discharge for 15 min;
e) Place it still for 30 min, or the shelving time specified by the manufacturer;
f) Modify the submitted SOCBMS value of the battery management system into
90%;
g) Adopt specific working conditions (see Appendix F, or, be determined by
OEMs and the manufacturers through negotiation); discharge, till the actual
SOC is 30%;
h) Place it still for 30 min, or the shelving time specified by the manufacturer;
i) In accordance with the charging specifications adopted in B.2, charge the
battery system, till the actual SOC is 80%;
j) Place it still for 30 min, or the shelving time specified by the manufacturer;
k) Repeat g) ~ j) twice;
l) During the test, implement real-time recording of the submitted SOCBMS value
of the battery management system;
m) During the test, implement real-time recording of the accumulative cyclic
charging and discharging capacity Q1 (charging is negative; discharging is
positive) of the test equipment; real-time SOC true value shall be calculated
SOCTrue Value
calculation of SOC error is .
C.2.2.3 In accordance with the following steps, test the error correction speed and
accuracy of upper biased estimated value when SOC is close to 30%:
a) In accordance with the charging specifications adopted in B.2, charge the
battery system;
b) Place it still for 30 min, or the shelving time specified by the manufacturer;
c) The test equipment begins to accumulate cyclic charging and discharging
capacity;
d) With 1 Q0 (A), discharge for 39 min;
e) Place it still for 30 min, or the shelving time specified by the manufacturer;
f) Modify the submitted SOCBMS value of the battery management system into
50%;
g) Adopt specific working conditions (see Appendix F, or, be determined by
OEMs and the manufacturers through negotiation); discharge, till the actual
SOC is 30%;
h) Place it still for 30 min, or the shelving time specified by the manufacturer;
i) In accordance with the charging specifications adopted in B.2, charge the
battery system, till the actual SOC is 80%;
j) Place it still for 30 min, or the shelving time specified by the manufacturer;
k) Repeat g) ~ j) twice;
l) During the test, implement real-time recording of the submitted SOCBMS value
of the battery management system;
m) During the test, implement real-time recording of the accumulative cyclic
charging and discharging capacity Q1 (charging is negative; discharging is
positive) of the test equipment; real-time SOC true value shall be calculated
by ;
n) During the full test process, calculate SOC error. The formula for the
calculation of SOC error is .
C.2.2.4 In accordance with the following steps, test the error correction speed and
SOCTrue Value
SOCTrue Value
Appendix D
(informative)
SOP Estimation Error Test Method
D.1 General
D.1.1 In accordance with the requirements of normal operation, assemble the battery
system to be tested (the smallest battery system suitable for the battery management
system may be selected).
D.1.2 Within the range of -20 °C ~ 65 °C, and the interval of 0 ~ 100%, OEMs and the
manufacturers shall, in accordance with the practical application, select at least three
temperature points. The three SOC points shall respectively receive pulse charging
and discharging test. In principle, the temperature points need to include low
temperature (≤ 15 °C), room temperature (25 °C ± 5 °C) and high temperature (≥ 35 °C).
SOC points need to include high end (≥ 80%), low end (≤ 30 °C) and intermediate
interval (30% < SOC < 80%). Under the selected test conditions, conduct the test
content specified in D.2.
D.1.3 In addition to the environmental adaptation process, when it is placed still during
the test, in accordance with the manufacturer’s technical specifications, it can be
determined whether the battery management is in the operating state.
D.1.4 When the target ambient temperature of the test changes, before the test, the
battery system needs to complete the environmental adaptation process: the battery
management system and accessories of the test object must be placed still for at least
1 h in the new test environment; the battery pack must be placed still in the new test
environment, till the difference between the surface temperature of the secondary cell
in the battery pack and the ambient temperature is less than 2 °C, then, it can be
considered that the environmental adaptation process of the battery system is
completed. During the process, the battery management system shall be in a non-
working state.
D.1.5 During the test, if the......
 
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