QC/T 897-2011Technical specification of battery management system for electric vehicles (English PDF)

3.1 Battery electronics

It is an electronic device which acquires the data of battery monomers (integrated) or battery modules (integrated) related to electricity and heat and provides such data for the battery control unit.

3.2 Battery control unit

It is an electronic control unit which controls or manages the electrical or thermal performance of the battery system and is capable of information interaction with other control units in the vehicles.

3.3 Battery management system

It is an electronic device composed of battery electronics and battery control system.

3.4 Battery pack

It is the energy storage unit, including integration of battery monomers or battery modules, battery electronics, high-voltage circuit, low-voltage circuit, cooling unit and mechanical assembly.

3.5 Battery system

It is the energy storage unit, including integration of battery monomers or battery modules, battery management system, high-voltage circuit, low-voltage circuit, cooling unit and mechanical assembly.

4.1 General requirements

4.1.1 The battery management system shall be capable of detecting the data of batteries related to electricity and heat, at least including the parameters such as voltage of battery monomers or battery modules, current of battery group return circuit and internal temperature of battery pack.

4.1.5 When the battery management system is used in an electric vehicle with the plug-in charging function, it shall capable of controlling and managing the charging process by real-time communication or other signal interaction modes with on-board or off-board battery charger.

4.2 Technical requirements

4.2.1 Insulation resistance

The insulation resistance value between the live parts, which are connected with the battery management system and power battery, and the shell shall not be less than 2 M±.

4.2.2 Insulation voltage withstand performance

The battery management system shall be capable of withstanding the insulation withstand voltage test as required by 5.3, without disruptive discharges such as breakdown or flashover during the test.

4.2.6 Overvoltage operation

The battery management system shall be capable of operating normally at the supply voltage specified in 5.7, and shall meet the requirements of 4.2.3 for the accuracy for the measurement of the state parameters.

4.2.7 Undervoltage operation

The battery management system shall be capable of operating normally at the supply voltage specified in 5.8, and meet the requirements of 4.2.3 for the accuracy for the measurement of the state parameters.

4.2.12 Resistance to temperature changes

The battery management system shall be capable of withstanding the temperature change test specified in 5.13, and shall be capable of normal operation after the test, and shall meet the requirements of 4.2.3 for the accuracy for the measurement of the state parameters.

4.2.15 Resistance to vibration

The battery management system shall be capable of withstanding the vibration test specified in 5.16, and shall be capable of normal operation after the test, and shall meet the requirements of 4.2.3 for the accuracy for the measurement of the state parameters.

4.2.16 Resistance to power polarity reversal

The battery management system shall be capable of withstanding the power supply polarity reversal test specified in 5.17, and shall be capable of normal operation after the test, and shall meet the requirements of 4.2.3 for the accuracy for the measurement of the state parameters.

5.1 Test conditions

Unless otherwise specified, the test shall be carried out at an ambient temperature of 18°C to 28°C, a relative humidity of 4.5% to 75%, and an atmospheric pressure of 86 kPa to 106 kPa.

5.1.2 Test voltage

14V ± 0.2 V (nominal 12 V) or 28 V ± 0.4 V (nominal 24 V), unless otherwise noted or specific to the manufacturer.

5.1.3 Test instrumentation

All test instruments, equipment shall have sufficient accuracy and stability, whose accuracy is higher than the measured index accuracy by an order of magnitude or error is less than 1/3 of the measured parameter tolerance.

5.2 Insulation resistance

Measure the insulation resistance by applying a voltage of 500 V DC between the voltage-sensing circuit of the battery management system and its shell.

5.3 Voltage withstand performance insulation

A sinusoidal waveform AC voltage of 50 Hz is applied between the voltage sampling circuit of the battery management system (corresponding to the positive pole of the battery system) and its shell. The test voltage (effective value) is the maximum operating voltage that can occur in this circuit (if less than 550V, the test voltage is 550 V). It lasts for 1 min.

5.5 Accuracy for SOC estimation

5.5.1 General rules

5.5.2 Available capacity test

Conduct the test in accordance with the procedures as follows. […]

5.5.3 SOC Test

5.6 Battery fault diagnosis

Establish the triggering conditions for the fault items listed in Table 2 through the simulation system, and record the corresponding fault items and their triggering conditions. Conduct function check for the other fault diagnosis items in accordance with the requirements of the manufacturer's specifications.

5.7 Overvoltage operation

Adjust the power supply voltage to 16 V or 32 V, operate continuously under the power supply voltage, record the data acquired by the battery management system during the test (not less than 2 voltage acquisition channels and not less than 1 temperature acquisition channel for the monomers or modules), and compare it with the corresponding data tested by the testing equipment.

5.10 Low-temperature operation

Place the battery management system in the operating state into an incubator with the initial temperature of room temperature, lower the temperature to -25°C ± 2°C before maintaining it for 1 h, record the data acquired by the battery management system during the test (not less than 2 voltage acquisition channels and not less than 1 temperature acquisition channel for the monomers or modules), and compare it with the corresponding data tested by the testing equipment.

5.11 Resistance to high temperature

Place the battery management system into an incubator with the initial temperature of room temperature, and maintain the temperature for 4 h after reaching 85°C ± 2°C.

Make the battery management system start to work after recovering to room temperature, record the data acquired by the battery management system (not less than 2 voltage acquisition channels and not less than 1 temperature acquisition channel for the monomers or modules), and compare it with the corresponding data tested by the testing equipment.

5.15 Resistance to heat and humidity

Conduct the damp heat test for the battery management system in accordance with the specifications of GB/T 2423.4 (at the high temperature 55°C). The test lasts for 2 cycles (48 h).

5.16 Resistance to vibration

Fix the battery control unit and the control unit of battery electronics (if any) on the vibration generator in accordance with the actual installation state of the complete vehicle or substantially equivalent conditions thereof, and conduct the sweep frequency vibration test in the three directions including up and down, left and right and front and back. The test in each direction lasts for 8 h. The vibration waveform of the test is sinusoidal.

5.17 Resistance to power polarity reversal

Set the input power supply to the reverse voltage value before connecting the power supply of the battery management system, and then maintain it for 1 min. Make sure the power supply of the battery management system is normal after the test, determine whether it is in a normal operating state, and record the data acquired by the battery management system if normal (not less than 2 voltage acquisition channels and not less than 1 temperature acquisition channel for the monomers or modules), and compare it with the corresponding data tested by the testing equipment.

5.18 Immunity to electromagnetic radiation

Conduct the test in accordance with the specifications of GB/T 17619. During the test, record the data acquired by the battery management system (not less than 2 voltage acquisition channels and not less than 1 temperature acquisition channel for the monomers or modules), and compare it with the corresponding data tested by the testing equipment.

6.1 Inspection categories

The inspection can be divided into exit-factory inspection and type inspection.

6.2 Exit-factory inspection

6.2.1 The battery management system can only be delivered after it passes the inspection of the quality inspection department of the manufacturer, and shall be accompanies by the certificate of conformity.

6.2.2 Batch. the products produced each day is a batch.

6.3 Type inspection

6.3.1 A type inspection shall be conducted in one of the following cases.

6.3.3 In the type inspection, if there are unqualified items, the number of samples shall be doubled from the batch of battery management systems for a reinspection on the unqualified items; and if the reinspection fails to pass, then the type inspection fails to pass.