GB/T 36944-2026General technical specification for electric bicycle chargers (English PDF)

6.2 Charging Parameters

6.2.1 Starting charging voltage The initial charging voltage should not be lower than 50% of the rated voltage of the compatible battery pack.

6.2.2 Output Voltage/Current

6.2.2.1 The deviation between the measured maximum output voltage of the charger and its stated maximum output voltage should be within ±1%.

6.2.2.2 For lead-acid batteries, the primary charger should have temperature compensation functionality, and the maximum output voltage should be able to adjust according to the ambient temperature. Adaptive adjustment. the difference between the highest output voltage values measured at 0°C and 40°C should be greater than 2.0V; this is not required for a two-stage charger. Function.

Note. See Appendix A for temperature compensation for lead-acid battery chargers.

6.2.2.3 For lithium or sodium-ion batteries, the primary charger should have temperature compensation functionality, and the rated output current should be able to adjust according to the ambient temperature. Adaptive adjustments should be made; the rated output current at 40°C should not be less than twice the rated output current at 0°C. This is not required for secondary chargers. Function.

6.2.3 Work Efficiency A wired charger operating at its rated output current should have an efficiency of no less than 85%. Wireless chargers should operate at their rated output current and their efficiency should not be less than 80%.

6.2.4 Ripple Coefficient The output ripple of a wired charger should not exceed 1% of its maximum output voltage. The peak ripple factor of a wireless charger should not exceed 5% in the high-voltage charging area.

6.2.5 Reverse Current The reverse current of a wired charger should not exceed 2mA.

6.3 Noise When tested according to the method described in 7.3, the operating noise of the charger should not exceed 60 dB(A).

6.4 Salt spray resistance After testing according to the method described in 7.4, the charger's plastic casing should be free from cracks and deformation; it should function normally; and its insulation resistance value should be greater than [value missing]. Or equal to 5MOmega.

6.5 Immunity

6.5.1 Electrostatic Discharge After testing according to the method described in 7.5.1, the charger shall meet the requirements of performance criterion B in Chapter 6 of GB/T 4343.2-2020.

6.5.2 Electrical Fast Transients After testing according to the method described in 7.5.2, the charger shall meet the requirements of performance criterion B in Chapter 6 of GB/T 4343.2-2020.

6.5.3 Injected Current After testing according to the method described in 7.5.3, the charger shall meet the requirements of performance criterion A in Chapter 6 of GB/T 4343.2-2020.

6.5.4 Radio Frequency Electromagnetic Field Radiation After testing according to the method described in 7.5.4, the charger shall meet the requirements of performance criterion A in Chapter 6 of GB/T 4343.2-2020.

6.5.5 Surge After testing according to the method described in 7.5.5, the charger shall meet the requirements of performance criterion B in Chapter 6 of GB/T 4343.2-2020.

6.5.6 Voltage Sag After testing according to the method described in 7.5.6, the charger shall meet the requirements of performance criterion C in Chapter 6 of GB/T 4343.2-2020.

6.6 Wired Charger

6.6.1 Output interface of lead-acid battery charger The output interface of the lead-acid battery charger is shown in Figure 2.

6.6.2 Lithium-ion battery charger output interface The output interface of the lithium-ion battery charger is shown in Figure 3.

6.6.3 Temperature Change After being tested according to the method described in 7.6.3, the charger should function normally and the insulation resistance value should be greater than or equal to 5MOmega.

6.6.4 Plug insertion and removal fatigue test After testing according to the method described in 7.6.4, the contact resistance of the charger should not exceed 10mOmega.

6.6.5 Minimum Cross-sectional Area of Conductor The charger shall be tested according to the method described in

7.6.5 and shall comply with the requirements of GB 42296.

6.6.6 Communication

6.6.6.1 General Rules The charger communicates with the battery through its output circuit. The communication system should have functions such as fault identification, transmission, and fault reporting.

6.6.6.2 Identification Phase The charger should have the function of sending a charging identification request to the battery. Upon receiving the charging identification request from the charger, the battery should then process the identified information. The system matches and judges the communication messages sent during the process. If the match is correct, charging proceeds normally; if the match fails 3 times in a row or within 30 seconds, charging stops.

6.7.1 Human Safety

6.7.1.1 Location of Anthropometric Points Select the locations of the human body measurement points as shown in Figure

4.The test limits should meet the requirements of Table 2.

6.7.2 Charging Power and Frequency Low-power wireless chargers should not exceed 80W in power and should operate at frequencies between 100kHz and 148.5kHz or 6765kHz. The operating frequency should be within the range of 6795kHz and 13553kHz~13567kHz; the power of a high-power wireless charger should not exceed 22kW, and the operating frequency should be within the range of 6795kHz and 13553kHz~13567kHz. 79kHz~90kHz; the error range of charging power should be within ±10%.

6.7.1.1 Human Body Measurement Points. And

6.7.1.2 Test the position of the vehicle body measurement points and record the results.

7.7.2 Charging Power and Frequency Connect the power analyzer to the output of the wireless charger and record the output power of the wireless charger; bring the probe of the spectrum analyzer close to the wireless charger. The transmitting coil of the wired charger records the frequency value corresponding to the signal peak displayed on the spectrum analyzer.

6.7.3 Safety Performance

6.7.3.1 Input Overvoltage Protection Wireless chargers should have overvoltage protection. When the input voltage exceeds the overvoltage protection value, the wireless charger should immediately disconnect. The current output is cut off and an alarm is issued. The overvoltage protection value should not exceed 120% of the rated output voltage.

6.7.3.2 Input Undervoltage Protection Wireless chargers should have undervoltage protection. When the input voltage drops below the undervoltage protection value, the wireless charger should immediately cut off power. The current output is cut off and an alarm is issued. The undervoltage protection value should not be lower than 80% of the rated output voltage.

6.7.3.3 Receiver end no-load protection Wireless chargers should have no-load protection for the wireless receiver. When the charging receiver is disconnected from the load, the wireless charger should immediately cut off the current. Output and issue an alarm message.

6.7.3.4 Communication Control Unit Communication Interruption Protection During charging operation, if the wireless charger communication control unit is interrupted, it should automatically stop charging.

6.7.4 Dustproof and waterproof

6.7.4.1 Dustproof After the wireless charger is tested according to the method described in 7.7.4.1, the wireless charger should function normally.

6.7.4.2 Waterproof After testing according to the method described in 7.7.4.2, the wireless charger should function normally and comply with

5.2.2 of GB 42296-2022. Regulation.

6.7.5 Communication

6.7.5.1 General Rules The input and output terminals of a wireless charger should establish a two-way communication link, and the communication system should have functions such as fault identification, transmission, and fault reporting.

6.7.5.2 Identification Phase The wireless charger should have the function of sending a charging identification request to the battery. Upon receiving the charging identification request from the wireless charger, the battery... Afterwards, device identity authentication, power level matching, and safety status verification are completed.

6.7.5.3 Transmission Phase After the battery and wireless charger are successfully identified, normal charging begins. Resonant frequency tracking, impedance matching adjustment, and electromagnetic field strength adjustment should be implemented. Dynamic control of key parameters such as temperature monitoring is required; communication latency should not exceed 50ms; and data update frequency should not be lower than 10Hz.

6.7.5.4 Transmission Failure The wireless charger should stop charging when identification fails, the working status is abnormal, or the communication interruption exceeds.200ms.

7.2 Charging Parameters

7.2.1 Starting charging voltage Connect the charger to the power supply, electronic load, and regulated power supply. Select the current mode for the electronic load (with current display), and select the regulated power supply voltage. Start from 0 and gradually increase the voltage until the charger has an output current, then record the voltage value at this point.

7.2.2 Output Voltage/Current

7.2.2.1 Connect the charger to a power supply, a voltage-mode electronic load, or a regulated power supply. Adjust the regulated power supply voltage until the charger draws current. After outputting, turn off the regulated power supply; adjust the electronic load to make the charger's operating voltage reach the maximum output voltage, and record the voltage value. The test can use a corresponding battery to replace the electronic load.

7.2.2.2 Place the charger or its temperature sensor into the high and low temperature test chamber, and adjust the chamber temperature to bring the sample to 0°C. Place the sample in the test chamber for 1 hour; conduct the test according to method 7.2.2.1, and record the highest output voltage value at low temperature. Then adjust the test chamber to ensure the sample is in the test chamber. Place at 40°C for 1 hour; conduct the test according to method 7.2.2.1, and record the highest output voltage value at high temperature. Calculate the highest output voltage at both high and low temperatures. Difference.

7.2.2.3 Place the charger or its temperature sensor into the high and low temperature test chamber, and adjust the chamber temperature to bring the sample to 0°C. Place in the specified state for 1 hour. Connect according to method

7.2.2.1 to bring the charger to normal operating condition, adjust the electronic load to simulate the battery's state. Record the charging status in the high-efficiency charging zone and the low-temperature current value. Then adjust the test chamber temperature to allow the sample to be placed at 40°C for 1 hour, and press the above... The experiment was conducted using the method described above, and the high-temperature current value was recorded. The ratio of the high-temperature current value to the low-temperature current value was calculated.

7.2.3 Work Efficiency

7.2.3.1 Wired charger Connect one power meter to the charger's output terminal, then connect it to the electronic load. Connect another power meter between the charger's input terminal and the power supply. Connect the power supply; select current mode for the electronic load. Adjust the regulated power supply voltage; once the charger outputs current, turn off the regulated power supply; adjust the voltage... The current of the sub-load is adjusted, and the charger output current is adjusted to the rated output current; the input power and output power are recorded, and the charging current is calculated according to formula (2). Device working efficiency.

7.2.3.2 Wireless Charger Perform the efficiency test according to the method described in 7.2.3.1.When the wireless charger is operating at its rated input voltage, perform the charging according to the manufacturer's specifications. The operating efficiency is tested at the electrical distance or at a distance of 30mm between the transmitter and receiver of the wireless charger, choosing the smaller value. Operating efficiency measurement... See Appendix B for the pilot program.

7.2.4 Ripple Coefficient Connect the circuit as shown in Figure

6.By adjusting the electronic load, test the charger when it reaches its highest output voltage. Adjust the oscilloscope to [range missing]. With a bandwidth of 20MHz, measure the peak-to-peak value of the charger's output voltage using the AC setting and record the output ripple.

7.2.5 Reverse Current Fully charge the compatible battery, and connect the ammeter in series between the output terminal of the wired charger and the input terminal of the compatible battery; connect the wired charger... Connect the input terminal of the device to a 220V AC power supply; disconnect the input wire of the wired charger and record the current value of the ammeter.

7.3 Noise Experiments were conducted in a semi-anechoic chamber.

a) Sound pressure level was measured using a first-class precision sound level meter;

b) Place the charger horizontally in the test area, with a vertical distance of 2m from its center at both the front and rear positions, and a height above the ground. One sound level meter was placed at a distance of 1.2m.

c) Under the charger's rated input voltage and normal operating conditions, record two sound level meter readings twice consecutively, and record the maximum reading of the sound level meter. Number (rounded to the nearest integer);

d) Then repeat steps

c) on the left and right sides of the charger;

e) At each measurement location, the difference between the sound pressure level of the sound source and the background noise sound pressure level is greater than 10 dB.

7.4 Salt spray resistance According to test method 3 in GB/T 2423.18-2021, the cycle period is 7 days. The test includes testing at (35±2)°C using... The test sample was sprayed with a neutral salt solution according to GB/T 2423.18-2021 for 2 hours, and then kept at (40±2)°C and (93±3)% relative humidity. The samples were stored under heat for 22 hours, repeated four times. Then, the samples were stored under standard atmospheric conditions at (23±2)°C and (50±5)% relative humidity. 3 days. After the test, the specimens were treated according to Chapter 10 of GB/T 2423.18-2021, and the insulation was measured according to the method described in

5.5 of GB 42295-2022. Insulation resistance.

7.5 Immunity

7.5.1 Electrostatic Discharge Perform electrostatic discharge testing on the charger according to the method described in Table 1 of section

5.1 of GB/T 4343.2-2020.

7.5.2 Electrical Fast Transients Charger electrical fast transient tests were performed according to the methods described in Tables 3 and 4 of section

5.2 of GB/T 4343.2-2020.

7.5.3 Injected Current The injection current test shall be performed according to the methods described in Tables 9 and 10 of section

5.4 of GB/T 4343.2-2020.

7.5.4 Radio Frequency Electromagnetic Field Radiation The charger's radio frequency electromagnetic field radiation was tested according to the method described in Table 11 of section

5.5 of GB/T 4343.2-2020.

7.5.5 Surge Charger surge tests shall be performed according to the method described in Table 12 of section

5.6 of GB/T 4343.2-2020.

7.5.6 Voltage Sag Perform the charger voltage sag test according to the method described in Table 13 of section

5.7 of GB/T 4343.2-2020.

7.6 Wired Charger

7.6.1 Output interface of lead-acid battery charger Check the charger casing or outer packaging markings to confirm the charger type and plug type. When there is no explicit label, the pin type can be measured using a multimeter in buzzer mode. Connect the black probe to the negative terminal of the charger, and the red probe to the corresponding pin. One pin emits a beep, which is the detection pin; the other pin is the communication pin. Alternatively, it can detect the voltage between the pins and the negative terminal. For chargers with communication capabilities, the signal is targeted accordingly. The negative terminal has a voltage of 5V. Record the location of the detection pins and communication pins, charger type, shorting method, and communication type. If voltage detection is involved, the voltage value must also be recorded.

7.6.2 Lithium-ion battery charger output interface Use the same method as in

7.6.1 to identify and confirm the charger type and plug type.

7.6.3 Temperature Change The charger was tested according to Test Nb as described in GB/T 2423.22.Low temperature TA was -20°C, high temperature TB was 55°C, and the holding time... The duration is 2 hours, and the number of cycles is 10; the rate of temperature change (decreasing or increasing) is greater than or equal to 1 K/min, and less than or equal to 1 K/min. 10K/min. After the test, the insulation resistance was tested according to the method described in section

5.5 of GB 42295-2022.

7.6.4 Plug insertion and removal fatigue test The charging plug insertion and removal fatigue test sequence is as follows:

a) Secure one end of the charger plug with a clamp;

b) Clamp one end of the plug socket with a force tester at a distance of 20mm from the insulating support;

c) The force tester inserts the plug into the charger plug at a uniform speed of 10 times/min, before reaching the expected stopping position. Previously, a force of less than 100N was continuously applied;

d) Then pull the charger plug out a certain distance in a straight line (not completely pulled out, maintaining some coupling at the end);

d) 1000 times for each sample;

f) After the test, let it stand for 24 hours, and then test the contact resistance according to the method described in

5.3.4 of GB 42295-2022.

7.6.5 Minimum Cross-sectional Area of Conductor Compare the manufacturer's stated upper limit for current limiting protection of the main circuit or secondary circuit with the measured value, and select the larger value to determine the conductor's current-limiting capacity. The maximum current to be carried is determined by referring to Table 1 in section

4.3.2 of GB 42295-2022 to determine the cross-sectional area of the conductor, and then according to GB/T 3956-2008. The method described in Chapter 7 for measuring the line resistance of a conductor shall be applied to the test results according to the temperature correction factors in Table A.1 of GB/T 3956-2008. Correction. Compare the corrected measurement results with Table 3 to determine whether the conductor resistance is qualified.

7.6.6 Communication Test using the testing tools provided by the manufacturer.

7.7 Wireless Charger

7.7.1 Human Safety When the wireless charger is operating at its rated input voltage, the time and frequency domains are measured using an electromagnetic field measuring instrument, according to section

7.7.3 Safety Performance

7.7.3.1 Input Overvoltage Protection When the wireless charger is operating at its rated input voltage, gradually increase the input voltage. When the input voltage exceeds the overvoltage protection value, observe the circuit. Does the corded charger cut off the current output and issue an alarm?

7.7.3.2 Input Undervoltage Protection When the wireless charger is operating at its rated input voltage, gradually reduce the input voltage. When the input voltage falls below the undervoltage protection value, observe the operation. Does the corded charger cut off the current output and issue an alarm?

7.7.3.3 Receiver end no-load protection When the wireless charger is operating at its rated input voltage, disconnect the load from the charging receiver and observe whether the wireless charger cuts off the current output. And issue an alarm.

7.7.3.4 Communication Control Unit Communication Interruption Protection When the wireless charger is operating at its rated input voltage, observe whether the charger cuts off power when communication between the transmitter and receiver is interrupted. Output stream and issue an alarm.

7.7.4 Dustproof and waterproof

7.7.4.1 Dustproof The test shall be conducted in accordance with the IP5X specification in section

13.4 of GB/T 4208-2017.

7.7.4.2 Waterproof The sprinkler head and sprinkler system conforming to the IPX5 specification and the methods described in GB/T 4208-2017 were tested. This test is now complete. Afterwards, let it stand for 10 minutes, and then test the electrical strength according to the method described in

6.2.2 of GB 42296-2022.

7.7.5 Communication Test using the testing tools provided by the manufacturer.

8.2 Factory Inspection

8.2.1 Inspection Plan According to the factory inspection items specified in Table 4, each product should be inspected before leaving the factory, and all of them should be qualified.

8.3 Periodic Inspection

8.3.1 Inspection Plan According to GB/T 2829-2025, a single sampling plan is adopted, and samples are drawn from the factory-inspected qualified products for inspection. The specific details of the test items, discrimination level (DL), nonconformity classification, rejection quality limit (RQL), sample size (n), and decision array should conform to Table 5. Or as required by Table 6.

9.1 Marking The contents of section

7.1 of GB 42296-2022 should be clearly marked on the charger body. Wired chargers should also be labeled as either a Level 1 charger or a Level 2 charger. A Level 1 charger should be marked "Level 1," and a Level 2 charger should be marked "Level 2." The character should be classified as "Level 2" and its height should not be less than 3.7mm.

9.2 Packaging

9.2.1 Products leaving the factory shall be accompanied by a product certificate, packing list, and product description.

9.2.2 Products should be individually packaged, with an outer cardboard box or other box, and securely bundled. In special circumstances, this may be done according to the buyer's (contract) requirements. Sure.

9.3 Transportation Packaging boxes containing products should be loaded, unloaded, and transported according to the packaging and storage diagrams. Handle with care during transport; do not throw. During transportation, it should not be exposed to sunlight or rain, and should not be transported together with flammable materials or active chemicals.

9.4 Storage

9.4.1 The product should be stored in a dry, well-ventilated indoor environment, protected from rain and snow. It should not be stored with corrosive substances such as acids and alkalis, or with dusty materials. The boxes containing the products should be placed properly and raised off the ground, with a minimum distance of 100mm from the ground, and the stacking height should not exceed 2m.

9.4.2 The shelf life of the product is usually 2 years.