The safety of LiFePO4 battery (lithium iron phosphate battery) under normal operation has been subjected to many technical tests and market tests. Its thermal runaway temperature is as high as 270°C (150°C for ternary lithium batteries), and even in an internal short circuit, the heat release rate is merely 0.2W/g (1.5W/g for ternary lithium batteries), which can effectively reduce the risk of fire. For instance, the certification test of UL 1973 found that the LiFePO4 battery merely reached 85°C under the needle-puncture test (the ternary lithium battery reached 420°C), and no open flame or explosion occurred. Based on the National Fire Protection Association (NFPA) statistics in 2022, the rate of accidents in LiFePO4 during lithium battery fires is merely 0.003% (0.12% for ternary lithium batteries).
Chemically, the cathode material of LiFePO4 battery (olivine phase) does not have oxygen release under overcharge or heat and the thermal decomposition temperature is ≥300°C (180°C for lithium cobalt oxide). 2021 tests at Tsinghua University showed that when the battery was charged to 150% capacity, only a 12°C rise (48°C in ternary lithium batteries) of the surface temperature and voltage oscillation were maintained within ±0.05V (BMS protection threshold) occurred. Besides, its electrolyte flash point is ≥200°C (the flash point of conventional lithium battery electrolyte is around 80°C), and no heavy metal (cobalt etc.) meets the RoHS environmental protection standard.
With the help of the battery Management System (BMS), the accuracy of voltage, temperature and current monitoring of LiFePO4 battery can reach ±0.5%, and the response time of overcharge/overdischarge protection is ≤50ms. For instance, a 200Ah LiFePO4 pack (48V system) is used in one particular power station of energy storage. BMS monitors individual cell voltage differences in real-time (≤0.02V), increasing cycle life to 6,000 times (retention rate capacity ≥80%), while out-of-control failure probability is merely 0.0001% (0.1% for lead-acid battery). As determined by German TUV in a report, the probability of safety accidents in LiFePO4 battery packs with BMS equipped is less than 0.001% in their 10-year period of service life.
Ensure the security by concrete application examples:
Electric vehicles: Tesla’s reports in 2023 show that the standard Model 3 with LiFePO4 batteries possesses 0.08 fire accidents per 100 million kilometers of operating mileage (0.34 for the model with ternary lithium batteries).
Home energy storage: Certain home energy storage devices (10kWh LiFePO4) in Europe experienced three outside short-circuit accidents in five years of use. The BMS successfully broke the circuit every time without causing any safety accidents.
In shipping: The DNV (Norwegian Classification Society) certified LiFePO4 Marine battery pack experiences a capacity loss rate of as little as 0.5% annually in the salt spray corrosion test (ASTM B117 standard) (3% for lead-acid batteries).
Environmental maintenance cost and flexibility: lifepo4 battery can usually operate between -20°C~60°C, with ≤80% capacity retention rate at low temperatures (the capacity of ternary lithium battery will decline to 60% at -10°C). In 2023, this battery was used by the Canadian Polar Research team to drive the equipment (load of 1kW) under ambient temperature of -30°C for 4 hours continuously without any failure, while lead-acid batteries failed after 1.2 hours under the same conditions. Also, its maintenance-free characteristic (no equalization charging or water topping up required) conserves a mean yearly maintenance expense of ¥200 (regular maintenance is necessary for lead-acid batteries).
Regulations and certification guarantee: LiFePO4 battery has received certificates such as UN38.3 (air transport), IEC 62619 (industrial application), and GB/T 36276 (Chinese national standard), which make the entire production chain and transportation secure. A 2022 report issued by the German Federal Environment Agency states that the recycling rate of LiFePO4 batteries is 98% (70% for ternary lithium batteries), and the recycling process does not release toxic gases, reducing environmental risk by 92%.
In short, LiFePO4 battery, with its superior thermal stability, intelligent BMS and strict certification, has greatly exceeded other lithium battery technologies in daily use safety. Furthermore, it enjoys superior long-term cost and environmental benefits, and is therefore the optimal energy storage solution for residential, transportation and industrial use.