GB/T 31467.3-2015Lithium-ion traction battery pack and system for electric vehicles - Part 3: Safety requirements and test methods (English PDF)

3.1 Battery electronics

Electronic device that collects and possibly monitors thermal or electric data of cells or cell assemblies. It may contain electronics for cell balancing, if necessary.

Note: The battery electronics can include a cell controller. The functionality of cell balancing can be controlled by the cell electronics or it can be controlled by the BCU.

3.2 battery control unit; BCU

Electronic device that controls, manage, detects or calculates electric and thermal functions of the battery system that provides communication between the battery system and other vehicle controllers.

3.3 Rated capacity

Total number of ampere-hours that can be withdrawn from battery pack or system for a specified set of test conditions.

3.4 Battery pack

Energy storage device that includes battery pack(s), battery management modules (BCU excluded), battery containers and accessories. It includes the units which can obtain and output power from external systems.

3.5 Battery system

Energy storage device that includes one or more of battery packs or accessories (management system, high voltage circuit, low voltage circuit, heat management devices and mechanical assemblies)

3.6 High voltage

A voltage with the maximum working voltage greater than 30 V a.c. (rms) and lower than or equal to 1000 V a.c. (rms), or greater than 60 V d.c. and lower than or equal to 1500 V d.c.

3.7 Low voltage

A voltage with the maximum working voltage greater than 30 V a.c. (rms) or not greater than 60 V d.c.

5.1 General conditions

5.1.1 Unless otherwise specified, the test temperature is 25°C±5°C and the test humidity is 15%~90%. The room temperature referred in this standard is 25°C±2°C.

5.1.2 A battery pack or system shall fulfill the relevant requirements in GB/T 18384.1 and GB/T 18384.3.

5.1.3 The necessary documentation for operation and needed interfaces connection to the test equipment (i.e. connectors, plug including cooling) shall be delivered together with the battery pack or system. The typical configuration of battery pack or system is shown in Annex A. The manufacturers shall prescribe the working limits of battery pack or system to ensure the safety of overall test process.

5.1.4 The protection level of battery pack and system shall fulfill the relevant requirements given in GB 4208.

5.1.5 As to the battery pack or system, the insulating resistance test shall be performed before starting all the tests. The test positions shall be at the positive electrode and casing OR the negative electrode and casing. The insulating resistance is required to be lower than 100 ohm/V.

5.1.6 When the target test environmental temperature is changed, all the test objects shall undergo the environmental adaptation before testing. The test objects shall be at the low temperature environment for at least 24 h and at the high temperature environment for at least 16h.

5.1.7 If the battery pack or system is not adaptive to some tests due to some reasons (i.e. dimension or weight), the subsystems of battery pack or system can be replaced as the test object to undergo all the tests or some of tests upon mutual agreement through friendly negotiation between supplier and purchaser. The subsystem as the test object shall comprise all the parts which fulfill the requirements of vehicle.

5.1.8 The method to adjust SOC to n% of the test target value. The battery pack or system shall be fully charged by the method prescribed by the manufacturer; stand for 1 h; then discharge at 1C for (100-n)/100 h. After the adjustment of SOC, the test object shall be tested for 30min before starting new test.

5.1.9 During the test, the internal response of battery pack or system shall be equilibrated. Therefore, certain time interval between test processes is required.

5.1.10 Discharging multiple-rate during the test shall be in accordance with the provisions of this Part. The charging mechanism and discharging shut-off conditions are prescribed by manufacturers.

5.1.11 The rated capacity of battery pack or system plays an important role in the test procedure. The deviation of the actual capacity of battery pack or system (6.2) and the rated capacity shall not exceed 5% of the rated capacity value.

5.1.12 Unless otherwise specified, all the test objects shall be tested under fully charged state as prescribed by manufacturer.

5.1.13 For the test items, article number of test method and test conditions of battery pack or system are shown in Annex B.

5.1.14 The symbol of discharging current of battery is positive, and the symbol of charging current is negative.

5.2 Accuracy requirements

5.2.1 The accuracy of measurement equipment shall be at least within the following tolerance.

5.2.2 During the test, the overall accuracy of externally controlled (actual) values relative to the target values shall be at least within the following tolerances.

5.3 Data record and the time interval for recording

Unless otherwise specified, the test data such as time, temperature, current and voltage shall be recorded at the interval of 1% of the predicted charging or discharging time.

5.4 Preparation for testing

5.4.1 Preparation of battery pack

Battery pack's high voltage, low voltage and cooling devices shall be connected to the test bench equipment. The passive protection of battery pack shall be activated. The working state and parameters of test bench equipment and battery pack shall fulfill the requirements and be tested according to test procedure as prescribed by the manufacturer of battery pack. The active protection shall be able to be activated through the shut-off of main connector of battery pack if necessary. The cooling device shall fulfill the working requirements of manufacturer. During the test, data is not exchanged between battery pack and test bench equipment. The parameter limits of battery pack shall be controlled by the test bench equipment. The current, voltage, capacity or energy parameters detected by the test bench equipment shall be served as the test results or the basis for calculation.

5.4.2 Preparation of battery system

Battery system's high voltage, low voltage, cooling devices and BCU shall be connected to the test bench equipment. The active and passive protections of battery pack shall be activated. The test parameters and conditions of the test bench equipment shall fulfill the requirements prescribed in the test procedure; the working parameters of battery system shall be within the reasonable limit range. The value limits shall be transmitted to the test bench equipment by the BCU via bus communication. The cooling device shall be operational according to the controls of the BCU. If necessary, the BCU program can be changed by the manufacturer of battery system according to the required test procedure.

During the test of battery system, the battery system transmits the parameters of battery state and working limits to the test bench equipment via bus communication; then the test bench equipment controls the test process according to the battery state and working limits.

The current, voltage, capacity or energy parameters detected by the test bench equipment shall be served as the test results or the basis for calculation. The uploaded parameters of battery system shall not be taken as the test result or the basis for test.

6.1 Measurement accuracy of state parameters

6.1.1 The accuracy of the state parameters of electronics of battery pack or system and BCU shall be tested before the formal start of test in order to confirm the accuracy of parameters during test.

6.1.2 The measurement accuracy of the state parameters of electronics of battery pack or system or BCU shall be within the values prescribed in Table 1.

6.2 Pre-conditioning test

6.2.1 The battery pack and system shall be conditioned before starting real test, in order to ensure an adequate stabilization of the battery pack or system performance.

6.2.2 The pre-conditioning cycles shall be conducted under room temperature according to the test procedure in GB/T 31467.1-2015 or 6.1 of GB/T 31467.2-2015.

The battery pack or system shall be considered as pre-conditioned if the discharge capacity during two consecutive discharges does not change by a value greater 3% of the rated capacity. If the time interval between standard cycle and new test is greater than 24h, a standard charge to the battery pack or system shall be re-conducted.

7.1 Vibration

7.1.1 Vibration test for battery pack or system [See Page 26 -- 2017 Modification List. Hereafter the same]

7.1.1.1 Reference shall be made to the installation position of test object vehicle and the relevant requirements given in GB/T 2423.43. Put the test object on the vibration bench.

The vibration test shall be conducted in three directions, from z-axis firstly and then y-axis and x-axis. The test procedure given in GB/T 2423.56 shall apply.

7.1.1.2 As to the test object installed at the bottom part of vehicle's passenger room, test parameters shall be selected from the values given in Table 2, 4, 5 and Figure 1. As to the test object installed at other positions, test parameters shall be selected from the values given in Table 2, 3, 5 and Figure 1.

7.1.1.3 The test time for each direction is 21h. If two test objects are tested at the same time, time can be reduced to 15h. If three test objects are tested at the same time, time can be reduced to 12h.

7.1.1.4 The state of the smallest monitor unit inside the test object shall be monitored in the course of test, such as voltage and temperature.

7.1.1.5 The test object shall be observed for 2h after vibration test.

7.1.2 Vibration test for electronic devices of battery packs or systems

7.1.2.1 For the test object installed on the wheel suspension of vehicle, vibration test shall be performed according to the test procedure in Figure 2 and Table 6. As to the test objects installed at other positions, the relevant test procedure given in GB/T 28046.3 shall apply.

7.1.2.2 For random vibration, the test procedure given in GB/T 2423.56 shall apply. For each face of test object, the vibration test shall be continued for 8h.

7.1.2.3 The test object during vibration test shall fulfill the requirements prescribed in GB/T 28046.1-2011 and work in the mode in 3.2.

7.1.3 Requirements

7.1.3.1 Battery pack or system. During the test, no voltage change for the smallest monitor unit of battery pack or system (the absolute value of voltage difference shall not be greater than 0.15V). The battery pack or system shall maintain reliable connection and complete structure and not exhibit evidence of leakage, rupture, fire, or explosion. The insulating resistance value after the test shall not be lower than 100 ohm/v.

7.1.3.2 Electronics of battery pack or system. During the test, electronics maintain reliable connection and complete structure without looseness. The accuracy of the measurement accuracy of state parameters after test shall be within the values given in Table 1.

No. 1 Modification List (2017): replacement text for 7.1.1 and 7.1.2

7.1.1 Vibration test for battery pack or system

Reference shall be made to the installation position of test object vehicle and the relevant requirements given in GB/T 2423.43. Put the test object on the vibration bench. Battery pack or system shall be subjected to sine wave vibration for 15 min, and the vibration frequency is increased from 7 Hz to 50 Hz and then decreased to 7 Hz. This cycle shall be repeated 12 times in 3 h in accordance with the vertical direction of the installation location of the battery pack or system specified by the manufacturer.

The relationship between vibration frequency and acceleration is shown in Table 2.

7.1.2 Requirements

7.1.2.1 During the test, the minimum monitoring unit of the battery pack or system has no voltage sharpening (the absolute value of the voltage difference is not greater than 0.15 V). The battery pack or system remains reliable connection and intact structure, the battery pack or system is free from leakage, enclosure rupture, fire or explosion. The insulation resistance after the test is not less than 100 ohm/V.

7.1.2.2 After the test, the battery pack shall be capable of completing a standard cycle as specified in 6.2 of GB/T 31467.1-2015 or 6.2 of GB/T 31467.2-2015 without interruption.

7.1.2.3 After the test, observe for 1 h at the ambient temperature of the test, the minimum monitoring unit of the battery pack or system shall have no voltage sharpness (the absolute value of the voltage difference is not more than 0.15 V). The battery pack or system remains reliable connection and intact structure, the battery pack or system is free from leakage, enclosure rupture, fire or explosion. The insulation resistance after the test is not less than 100 ohm/V. [see No. 1 modification list]

7.2 Mechanical shock

7.2.1 The test object is battery pack or system.

7.2.2 Apply the half sine shock waveform shock of 25g, 15ms at the axis directions to the test object for 3 times. The test object shall be observed for 2h.

7.2.3 Requirements. Battery pack or system shall not exhibit evidence of leakage, rapture, fire or explosion. The insulating resistance value after the test shall not be lower than 100 ohm/v.

7.3 Falling

7.3.1 The test object is battery pack or system.

7.3.2 The test object shall be fallen at the direction where the object may most likely be fallen during real maintenance or installation. If the direction cannot be confirmed, drop the object along the direction of Z-axis at the height of 1m to the cement ground. The test object shall be observed for 2h.

7.3.3 Requirements. Battery pack or system shall not exhibit evidence of leakage, rapture, fire or explosion.

7.4 Rotation

7.4.1 The test object is battery pack or system.

7.4.2 The test object is rotated around X-axis by 360° at the speed of 6°/s; then rotated at the increment of 90°. Keep for 1h for each increment of 90°. If it is rotated for 360°, stop it. The test object shall be observed.

7.4.3 The test object is rotated around Y-axis by 360° at the speed of 6°/s; then rotated at the increment of 90°. Keep for 1h for each increment of 90°. If it is rotated for 360°, stop it. The test object shall be observed.

7.4.4 Requirements. Battery pack or system shall not exhibit evidence of leakage, rapture, fire or explosion and maintain reliable connection and complete structure. The insulating resistance value after the test shall not be lower than 100 ohm/v.

7.5 Simulated collision

7.5.1 The test object is battery pack or system.

7.5.2 The test object shall be installed on the trolley with holder horizontally. The impulse as specified in Table 7 and Figure 3 shall be applied to the trolley The impulse as specified in Table 3 and Figure 1 shall be applied to the trolley [see No. 1 modification list] according to the actual environment (the driving direction of vehicle is X-axis, and the other direction vertical to the driving direction is Y-axis). The test object shall be observed for 2h.

7.5.3 Requirements. Battery pack or system shall not exhibit evidence of leakage, rapture, fire or explosion. The insulating resistance value after the test shall not be lower than 100 ohm/v.

7.6 Squeezing

7.6.1 The test object is battery pack or system.

7.6.2 The test object shall be squeezed according to the following conditions.

- Form of squeezing plate. A semi-cylinder with the radius of 75mm and the length longer than the height of test object but not exceeding 1m.

- Squeezing direction. X- and Y-axis (the driving direction of vehicle is X-axis, and the other direction vertical to the driving direction is Y-axis).

- The degree of squeezing. Stop squeezing when squeezing force reaches 200 kN squeezing force reaches 100 kN [see No. 1 modification list] or the deformation due to squeezing reaches 30% of the overall dimension at the squeezing direction. Maintain for 10 min.

- Observe for 1h.

7.6.3 Requirements. Battery pack or system shall not exhibit evidence of leakage, rapture, fire or explosion.

7.7 Temperature shock

7.7.1 The test object is battery pack or system.

7.7.2 The test object shall be at the high and low temperature alternating environment of (-40±2)°C~(85±2)°C for not more than 30 min. The test object shall be at the extreme temperature environment for 8h which shall be cycled for 5 times. The test object shall be observed under room temperature for 2h.

7.7.3 Requirements. Battery pack or system shall not exhibit evidence of leakage, rapture, fire or explosion. The insulating resistance value after the test shall not be lower than 100 ohm/v.

7.8 Thermal shock cycling

7.8.1 The test object is battery pack or system.

7.8.2 The test procedure given in GB/T 2423.4 shall apply. Db and variables are shown in Figure 4 variables are shown in Figure 2 [see No. 1 modification list]. The maximum temperature is +80°C. The test shall be cycled for 5 times. The test object shall be observed under room temperature for 2h. Key. […]