If the remaining capacity/initial capacity=80% is used as the end point of the test, the current 1C cycle life of the lithium iron phosphate battery laboratory is more than 3500 times, and some reach 5000 times, while the 1C cycle life of the ternary lithium ion battery laboratory is 2500 times about. In terms of the true cycle life, the lithium iron phosphate battery pack has a much longer true cycle life than the ternary lithium ion battery. Under the same number of cycles, the remaining capacity of the lithium iron phosphate battery is much more than that of the ternary lithium ion battery.
According to laboratory data, the remaining capacity of the ternary lithium ion battery after 3900 cycles is 66%, and the remaining capacity of the lithium iron phosphate battery after 5000 cycles is 84%. The battery cycle life of the lithium iron phosphate material is higher than that of the ternary material lithium ion battery. Lithium iron phosphate batteries have obvious advantages.
Theoretically speaking, the life of a ternary lithium-ion battery is 2000 charge-discharge cycles. If we count it as one charge per day, it can last for more than 5 years. However, there is still a difference between actual use and theory. If 1,000 charge-discharge cycles are performed, the ternary lithium-ion battery has actually attenuated by 50%, which means that it can only run half of the original mileage on a full charge.
When the quality of the lithium iron phosphate battery is relatively good, the capacity degradation can be controlled within 5% in the first year and within 15% in the second year. The capacity attenuation of the ternary lithium-ion battery type decreases by 7-10% in the first year and 20-25% in the second year. Of course, the details are also related to the usage load and usage frequency. This is just a general expression.
Lithium iron phosphate battery packs have longer cycle life than lead-acid batteries and ternary lithium-ion batteries. The long life of lead-acid batteries is only about 300 times; the ternary lithium-ion battery theoretically can reach 2000 times, and the capacity will decrease to 60% when it is actually used about 1000 times; and the true life of lithium iron phosphate battery is 2000 times, at this time, there is still 95% capacity, and its ideal cycle life can reach more than 3000 times.
Based on various factors, the use characteristics of lithium iron phosphate battery packs can be roughly expressed as: relatively large size, poor low-temperature performance, and can maintain a relatively flat decay rate during the lifespan, generally about 8 years.
