Regarding the claim that lithium iron phosphate batteries perform poorly in winter, it's true that lithium iron phosphate batteries do experience slightly greater range degradation than ternary lithium batteries in low temperatures, but the difference is not significant. Under the same conditions, a vehicle equipped with a ternary lithium battery might see a 25% reduction in range due to low winter temperatures, while a lithium iron phosphate battery could potentially see a 30% reduction. The difference is minimal and not as large as some online rumors suggest. Furthermore, this difference is not entirely determined by the inherent properties of the batteries themselves.
Comparison of Lithium Iron Phosphate and Ternary Lithium Batteries
1. Energy density
Battery energy density is an index that affects the driving range of new energy vehicles. The energy density of lithium iron phosphate battery cells is only around 110Wh/kg, while the energy density of ternary lithium battery cells is generally around 200Wh/kg. This means that for the same weight of battery, ternary lithium batteries have 1.7 times the energy density of lithium iron phosphate batteries, enabling new energy vehicles to achieve longer driving ranges.
2. Safety
Lithium iron phosphate (LFP) batteries currently boast the best thermal stability among power batteries, offering a significant safety advantage over ternary lithium batteries. LFP batteries have a peak thermal temperature of up to 350℃, and their internal chemical components only begin to decompose at 500-600℃; in contrast, ternary lithium batteries exhibit only moderate thermal stability, starting to decompose around 300℃.
3. Charging efficiency
Ternary lithium batteries are more efficient. Experimental data shows that there is little difference between the two when charging below 10°C, but the difference becomes significant above 10°C. When charging at 20°C, the constant current ratio of ternary lithium batteries is 52.75%, while that of lithium iron phosphate batteries is 10.08%, with the former being five times that of the latter.
4. Cycle life
Lithium iron phosphate batteries have a longer cycle life than ternary lithium batteries. The theoretical lifespan of ternary lithium batteries is 2,000 cycles, but their capacity typically decreases to 60% after about 1,000 cycles. Even Tesla, a top performer in the industry, can only retain 70% of its capacity after 3,000 cycles, while lithium iron phosphate batteries can still retain 80% of their capacity after the same number of cycles.
In comparison, lithium iron phosphate batteries are safer, have a longer lifespan, and are more resistant to high temperatures; ternary lithium batteries are lighter, have higher charging efficiency, and are more resistant to low temperatures. Therefore, the differences between the two lead to their respective time- and location-dependent adaptability, which is the reason for their coexistence.
