GB 43854-2024Safety technical specification of lithium-ion battery for electric bicycle (English PDF)

5.1 Cell safety requirements

5.1.1 Overcharge When tested according to the test method in 6.3.1, the cell shall not catch fire or explode.

5.1.2 Over discharge When tested according to the test method in 6.3.2, the cell shall not catch fire or explode.

5.1.3 External short circuit When tested according to the test method in 6.3.3, the cell shall not catch fire or explode.

5.1.6 Marking The cell shall be clearly marked with at least the following signs in a conspicuous location.

5.2.1 Electrical safety

5.2.1.1 Electrostatic discharge After the test according to 6.4.1.1, the overcharge protection and short circuit protection functions of the battery shall be normal.

5.2.2 Mechanical safety

5.2.2.1 Extrusion When tested according to the test method in 6.4.2.1, the battery shall not catch fire or explode.

5.2.2.2 Acceleration shock When tested according to the test method in 6.4.2.2, the battery shall not leak, rupture, catch fire or explode.

5.2.2.3 Vibration When tested according to the test method in 6.4.2.3, the battery shall not leak, rupture, catch fire or explode.

5.2.2.4 Free fall When tested according to the test method in 6.4.2.4, the battery shall not catch fire or explode.

5.2.2.5 Hander strength When tested according to the test method in 6.4.2.5, the hander of the battery shall not break, and the connection between the handle and the case shall not crack or fall off.

5.2.3 Environmental safety

5.2.3.6 Flame retardancy When tested according to the test method of 6.4.3.6, the non-metallic casing of the battery shall meet the requirements of V-0 level; the printed circuit board shall meet the requirements of V-1 level; and the insulation of the wires shall not contribute to the spread of flames.

5.2.4 Heat diffusion When tested according to the test method in 6.4.4, the battery shall not catch fire or explode within 5 minutes after the thermal runaway alarm is issued.

5.2.5 Mutual recognition and coordinated charging The battery shall have the function of mutual recognition and coordinated charging with the charging device. When tested according to the test method in 6.4.5, the battery shall first be mutually recognized and collaboratively identified with the charging device, and charging can only begin after the mutual recognition and collaborative identification are passed.

5.2.6 Data collection During the battery charging and discharging processes, at least the following data such as cell voltage, battery total voltage, temperature, and current, shall be collected in real time.

5.2.7 Marking The battery shall be clearly and durably marked with at least the following marks in a conspicuous location.

6.1 Test conditions

6.1.1 Environmental requirements Unless otherwise specified, the tests shall be carried out in the following environment. Temperature. (20±5) °C; relative humidity. not more than 85%; atmospheric pressure. 86 kPa~106 kPa.

6.1.2 Requirements for measuring instruments and equipment The accuracy of measuring instruments and equipment shall not be less than the following.

6.1.3 Single fault condition If it is required to apply simulated faults or abnormal operating conditions, they shall be applied sequentially, simulating one fault at a time. Faults directly caused by the simulated fault conditions (such as direct damage to the device) are considered to be part of the fault conditions.

6.2.1 Cell sample preparation

6.2.1.1 Standard charging If the company does not provide a charging method, the cell is charged using the following method.

6.2.1.2 Standard discharge Under the test environment of (23±2) °C, after the cell is charged according to the method in 6.2.1.1, it is discharged at a constant current of I2(A) to the end-of-discharge voltage.

6.2.2 Battery sample preparation

6.2.2.1 Standard charging If the company does not provide a charging method, the battery is charged using the following method.

6.3 Cell safety test

6.3.1 Overcharge test After the cell is fully charged according to the test method in 6.2.1.1, use a DC power supply to charge at a current of I2(A) to

1.5 times the limited charging voltage or the total charging time reaches

1.5 h, stop charging, and then let it stand for 6 h.

6.4.1 Electrical safety

6.4.3.3 Water immersion test After the battery is fully charged according to the test method in 6.2.2.1, it is immersed in a water tank at a temperature of (20±5) °C (based on the water submerging the top of the battery) for 48 hours, and then taken out and left to stand for 4 hours.

6.4.3.6 Flame retardancy test The non-metallic case and printed circuit board of the battery shall be tested in accordance with GB/T 5169.16; the wires shall be tested in accordance with Appendix A.

6.4.4 Thermal diffusion test

6.4.4.1 Trigger method Heating or overcharging is recommended as an optional method for thermal diffusion testing. Either method can be selected, but the selected method shall be able to trigger the thermal runaway of the cell.

6.4.4.2 Trigger object After the battery is charged according to 6.2.2.1, select a cell near the center of the battery or surrounded by other cells as the trigger object.

6.4.4.3 Heating trigger Heating-triggered thermal runaway method. Use a flat or rod-shaped heating device, and its surface is covered with a ceramic or insulating layer. 6.4.4.5; after installation, start the heating device within 24 hours and heat the trigger object with the maximum power of the heating device; the power requirements for the heating device are shown in Table 2, and the heating power can be increased if necessary to ensure that the trigger object has thermal runaway; stop heating when the trigger object has thermal runaway.

6.4.4.4 Overcharge trigger Overcharge triggered thermal runaway method. Charge the trigger object with constant current at the maximum current that the battery can continuously operate until thermal runaway occurs or the stage-of-charge of the trigger object reaches 3 times the rated capacity of the battery;

6.4.4.5 Monitoring point layout plan Follow the scheme below.

6.4.4.6 Judgment conditions for battery thermal runaway triggering The judgment conditions are as follows:

6.4.4.7 Records Record the time from when the battery issues a thermal runaway alarm to when it catches fire or explodes, as well as the battery status within 1 hour after the thermal runaway of the cell is triggered. If the battery does not catch fire or explode, it is considered that the battery has passed the thermal diffusion test.

6.4.5 Mutual recognition and coordinated charging test The test method for the mutual recognition and coordinated charging function between the battery and the charging device is as follows:

6.4.6 Data collection test Perform data collection and verification according to the communication method or host computer provided by the manufacturer.

6.4.7 Marking The marking test is carried out as follows: