Pacific Automotive Network lithium iron phosphate batteries are greatly affected by temperature, and thermal management of the battery is necessary to improve its efficiency. At a temperature of 0 ~ -20°C, the discharge capacity of lithium iron phosphate battery is equivalent to 88.05%, 65.52% and 38.88% of the discharge capacity at 25°C respectively, the average discharge voltage is 3.134, 2.963 V and; 2.788 V, respectively. The average discharge voltage at 20°C is 0.431 V lower than that at 25°C.
The minimum charging temperature of the lithium iron phosphate battery is -20°C. The battery will not exceed 20°C. If it is less than this value, it means it should be loaded. is greater than this voltage, it is basically almost full. Continuing to charge will cause the voltage to rise rapidly, the maximum voltage when full is 3.9V.
During dischargingge, the voltage drops quickly from 3.9 V to 3.2 V and remains stable until the end of the discharge. At the end, the voltage drops quickly by 3.2 V. At this point, the energy can be considered exhausted.
Generally speaking, discarded lithium iron phosphate batteries for electric vehicles still have nearly 80% of their capacity, and they still have 20% of their capacity remaining before the lower limit of 60 % of their complete disposal. be used for applications with lower electrical power requirements than cars, such as low-speed electric vehicles, communication base stations, etc., realize the step-by-step utilization of waste batteries. Lithium iron phosphate batteries removed from cars still have high usage value.
The process of phased use of power batteries is as follows: companies recycle worn-out batteries - dismantleage - testing and classification - classification by capacity - reorganization of battery modules. At the battery preparation level, the residual energy density of used lithium iron phosphate batteries can reach 60 ~ 90 Wh/kg, and the recycling life can reach 400 ~ 1,000 times. As the battery preparation level increases, the recycling life can be further improved; and energy Compared with lead-acid batteries with a service life of 45 Wh/kg and a service life of about 500 times, used lithium iron phosphate batteries still have performance advantages. In addition, the cost of used lithium iron phosphate batteries is relatively low, only 4,000-10,000 yuan/t, which is very economical.
(Images/Text/Photos: Pacific Automotive Network Q&A)
The operating voltage of ordinary lithium batteries is 3.7V and the voltage oftermination is 3.2V. The working voltage of lithium iron phosphate battery is 3.26V and the termination voltage is 2.5V. Lithium battery is a primary battery that uses lithium metal or lithium alloy as the negative electrode material and uses a non-aqueous electrolyte solution. It is different from rechargeable batteries, lithium-ion batteries and lithium-ion polymer batteries. The inventor of lithium batteries is Edison. Since the chemical properties of lithium metal are very active, the processing, storage and use of lithium metal are subject to very high environmental requirements.