Lithium iron phosphate battery detection method and standard analysis

1. Lithium iron phosphate battery charge detection is under the condition of 20℃±5℃, the lithium iron phosphate battery is discharged with 1 (A) current until the battery voltage reaches 2.0V, stand for 1h, and then under the condition of 20℃±5℃ 1 (A) Constant current charging, when the battery voltage reaches 3.65V, switch to constant voltage charging, and stop charging when the charging current drops to 0.1. After charging, let it stand for 1h. Lithium iron phosphate battery 2. Lithium iron phosphate battery 20℃ discharge capacity a) Lithium iron phosphate battery is charged according to 1.1 method. b) The lithium iron phosphate battery is discharged at a current of 1 (A) at 20°C ± 5°C until the discharge end voltage is 2.0V. c) Calculate the capacity (in A.h) with the current value of 1 (A) and the discharge time data. d) If the calculated value is lower than the specified value, you can repeat steps a) and c) until it is greater than or equal to the specified value, allowing 5 times. During the inspection, its capacity should not be lower than the rated value specified in the technical conditions supplied by the company, and the capacity should not be higher than 110% of the rated value specified in the technical conditions supplied by the subsidiary. 3. Discharge capacity of lithium iron phosphate battery at -20°C a) Charge the lithium iron phosphate battery according to the method 1.1. b) Lithium iron phosphate battery is stored at -20℃±2℃ for 20h. c) The lithium iron phosphate battery is discharged at a current of 1 (A) at -20°C ± 2°C until the discharge end voltage is 2.0V. d) Use c) current value and discharge time data to calculate capacity (in A.h) and express it as a percentage of discharge capacity at 20°C. During the experiment, its capacity should not be less than 70% of the rated value 4, -40℃ discharge capacity a) Lithium iron phosphate battery is charged according to 1.1 method. b) Lithium iron phosphate battery is stored at -40℃±2℃ for 20h. c) The lithium iron phosphate battery is discharged at a current of 1 (A) at -40°C ± 2°C until the discharge termination voltage is 2.0V. d) Use c) current value and discharge time data to calculate capacity (in A.h) and express it as a percentage of discharge capacity at 20°C. During the experiment, its capacity should not be less than 50% of the rated value. Note: 1-3h rate discharge current, its value is equal to C3/3. C3-3h rate rated capacity (Ah). 5. High temperature charge retention and capacity recovery capability: a) Lithium iron phosphate battery is charged according to 1.1 method. b) Lithium iron phosphate battery is stored at 60℃±2℃ for 7 days. c) After the lithium iron phosphate battery is recovered at 20℃±5℃ for 5 hours, discharge it with 1 (A) current until the discharge termination voltage is 2.0Vd) Use the current value of c) and the discharge time data to calculate the capacity (in Ah), The charge retention capacity can be expressed as a percentage of the rated capacity. e) The lithium iron phosphate battery is recharged according to method 1.1. f) The lithium iron phosphate battery is discharged at a current of 113 (A) at 20°C ± 5°C until the discharge end voltage is 2.0V. g) Use the current value and discharge time data of f) to calculate the capacity (in A-h). The capacity recovery capacity can be expressed as a percentage of the rated capacity. During the experiment, the normal temperature and high temperature charge retention rate should not be less than 92% of the rated value, and the capacity recovery capacity should not be less than 94% of the rated value. 6. Cycle life a) Then charge at a constant current of 9I? (A) at 20℃±5℃, switch to constant voltage charging when the battery voltage reaches 3.65V, and stop charging when the charging current drops to 0.1Is. After charging, let it stand for 1h. b) The lithium iron phosphate battery is discharged at a current of 91 (A) at 20°C ± 2°C, and then left to stand for 15 minutes after discharge. c) The lithium iron phosphate battery is charged according to a) method. d) Repeat steps b)-c) for lithium iron phosphate batteries several times. e) Check the capacity according to 1.2 method. If the capacity of the lithium iron phosphate battery is less than 92% of the rated capacity, terminate the experiment. f) The number of repetitions of steps b)-e) under specified conditions is the number of cycle life. During the experiment, its cycle life should be no less than 300 times. 7. High-temperature full-charge storage a) The battery is charged according to the method 1.1. b) Store the battery in an environment of 85℃±2℃ for 24h, and observe the condition of the battery. During the experiment, the battery cap CID (CurrentInterruptDevice) cannot be broken or the cap explosion-proof valve cannot be opened. 8. AC internal resistance detection detection conditions: temperature 20℃±2℃, AC frequency: 1KHZ. During the experiment, its AC internal resistance ≤ 10m. Disclaimer: Some pictures and contents of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous article: Do you know what battery Tesla uses?