1. Insulation resistance test;
2. Constant voltage DC load test;
3. Vibration test;
4. Environmental testing;
5. Temperature cycle test;
6. External short circuit test;
7. 8. Mechanical impact test;
9. Thermal shock test;
10. Extrusion test;
11. Low pressure test;
12, overload test;
13. Forced discharge test;
14. High-rate charging protection test of battery core (lithium system); Forced internal short circuit test;
16. Testing the battery overload protection function;
17. Free fall testing of equipment.
The above is compiled by Younai Testing. I hope it will be useful to you. If you have further questions, you can consult Younai Testing
Analysis of common defective items and causes. 18650 batteries:< p>1. Zero voltage from a single batteryp> 1) If the battery has been over-discharged or reverse-charged (reverse the positive and negative poles of the battery or the positive and negative poles of the charger, the battery (this is equivalent to forced over-discharge during charging ); whether the circuit of the electrical appliance is normal 2) Whether the battery works continuously; overloaded by large current, causing the battery to expand and the internal positive and negative electrodes to directly contact and short circuit. 3) Has the battery been crushed or impacted from the outside, causing the battery's internal separator to pass through and the positive and negative electrodes to short circuit? --Visual inspection 4) If the packaging film is damaged, long-term exposure to air humidity, electrolyte failure --- visual inspection
6) Check the spot welded battery for signs of burning or spot welding has broken the diaphragm and short circuited--------Visual inspection
7) Internal micro-short circuit
Treatment method:
In addition to visual judgment:
1) Understand the specific use of the customer's battery situation;
2) Charge the battery of the same model and connect it to the electrical appliance to determine whether the electrical appliance is normal;< /p>
3) Charge the battery with 1C current for 30 minutes and leave it in open circuit for 10 minutes. If the battery's open circuit voltage is stable within the battery's normal voltage range, the battery can return to normal. If the battery has been damaged, voltage cannot be restored; if the battery has not been used and this phenomenon occurs, the voltage cannot be restored with a charge 1C and further analysis by professional technicians is necessary.
2. The battery or battery cannot be charged
1) Check if the battery or battery has zero voltage., battery at high internal resistance;
2)? Check the battery connection, electronic components and protection circuit for abnormality;
3)? Check the charging status of the charging equipment or charging circuit. Is there a charging voltage/current output?
4)? Check if the user circuit design has a low load voltage limit
5) Is the ambient temperature too high? in low charging efficiency (the maximum optimum temperature should not exceed 40℃);
Processing method:
1) Understand the customer's specific usage and conditions; battery ;
p> 2) Take a battery of the same model et a multimeter (current level) and connect them to the charging circuit. According to the value of the charging current, determine. whether the charging equipment is normal. 3) Repeat the analysis and processing of the tension-free step of individual cells; 4) Customers are recommended to choose charging equipment or charging circuits with better stability;
Phenomenon: After charging, the device cannot work when installed in the device, and the open circuit voltage of the battery does not change or changes little< /p>
1) ? Check the battery/Is the battery a zero voltage, high internal resistance battery?
2) Are the electronic components and protection circuits inside the battery damaged? > 3)? Check if the discharge circuitThe age of the equipment is normal.
4)? Does the customer's discharge current exceed the range allowed by specifications?
5? Is the ambient temperature too low, resulting in low charging efficiency (should the optimum temperature be reached? should not be lower than -20°C);
Solution:
1) Use a fully charged battery/battery pack of the same model to connect to the device to see if the device working properly;
2) Use a multimeter to check whether the electronic components and protection circuits inside the battery are normal.
3) Repeat the analysis and processing of the single battery zero voltage stage;
4) If the discharge circuit of the electrical appliance is abnormal, the customer is recommended to repair or replace the electrical appliance in time;
p>
5) If the customer has not modified the batteryby itself, specialized technical personnel are required for further analysis.
?4. Battery leak (leak)
? Phenomenon: battery cylindrical cap leakage, coin cell battery gasket leakage, polymer battery leakage of packaging film or tabs1) Check whether the battery/pack -battery is overcharged or over-discharged ---- Check customer usage records or test records
2) Check whether the battery/battery pack has been deformed or leaked due to of extrusion or impact--------Visual inspection
3)? scratched by foreign objects Break the packaging film----------------Visually check whether there are foreign objects or sharp protrusions in the space where the battery is installed in the electrical appliance
4) Check the battery. Is there an external short in the core and are there signs of burning in thetabs ---- Visual inspection
5)? too high, resulting in significant internal pressure leakage (optimum temperature should not exceed +60 ℃)
6)? the battery itself, and it must be sent back to the factory for analysis.
The analysis of the above reasons is based on common problems that occur in batteries. The analysis is applicable to lithium batteries from any manufacturer. I hope it will be useful. to you, thank you!