Currently, mainstream new energy vehicles in my country primarily use lithium iron phosphate or ternary lithium batteries as their cathode materials, each with its own advantages in the new energy bus and passenger vehicle sectors. So, which is better: lithium titanate batteries, lithium iron phosphate batteries, or ternary lithium batteries?
This requires discussing the performance of the three types of batteries. As we all know, the performance of lithium-ion batteries is mainly determined by the positive electrode, negative electrode, electrolyte, and separator. Among them, the positive and negative electrode materials have a significant impact on key battery indicators such as capacity, energy density, cycle life, safety, rate performance, and cost.
Although both lithium titanate batteries use ternary cathode materials, they break away from the traditional battery technology route of using graphene as the anode material, instead using lithium titanate, making them an outlier in the eyes of their peers. However, it is precisely the inherent properties of lithium titanate that give these batteries their distinctive characteristics.
Taking lithium iron phosphate-graphene, ternary-graphene, and ternary-lithium titanate batteries as examples, lithium titanate batteries are at a disadvantage in terms of energy density alone. A research report from Northeast Securities points out that the actual specific energy of lithium iron phosphate batteries is currently 100-120 Wh/kg, while ternary batteries are 150-200 Wh/kg. TSLA's nickel-cobalt-aluminum ternary battery even reaches 252 Wh/kg, while Yinlong's lithium titanate battery is only 90 Wh/kg, half that of some graphite-based anode material batteries.
From a cost perspective, lithium titanate batteries also lack an advantage. Currently, the raw materials for Yinlong's lithium titanate batteries include titanium hydroxide and lithium hydroxide, which are more expensive than graphite-based anode materials. According to a survey by my country Battery Network, the current cost of lithium iron phosphate and ternary batteries is between 1100 and 1200 yuan/kWh, while the cost of lithium titanate batteries is approximately 2-3 times that of ternary batteries.
With half the energy density and 2-3 times the cost, how can lithium titanate batteries compete in the market? Clearly, it is their unique advantages that have impressed some industry insiders.
First, considering the most important safety indicator of batteries, lithium titanate stands out.
Lithium titanate, when used as an anode material, has a high potential plateau of 1.55V, more than 1V higher than traditional graphite anode materials. Although this results in some loss of energy density, it also means the battery is safer. Technical expert Lu Languang stated that batteries require a lower anode voltage during fast charging, but if the voltage is too low, lithium-ion batteries are prone to depositing highly reactive metallic lithium. These lithium ions are not only conductive but can also react with the electrolyte, releasing heat, producing flammable gases, and potentially causing a fire. The 1V higher voltage of lithium titanate prevents the anode voltage from reaching zero, indirectly preventing lithium ion deposition and thus ensuring battery safety.
Because lithium titanate batteries can be used safely in both high and low temperature environments, they demonstrate a significant advantage in terms of wide temperature range (especially low temperature resistance). Currently, Yinlong lithium titanate batteries have a safe operating temperature range between -50°C and 65°C, while ordinary graphite-based negative electrode batteries begin to degrade in energy below -20°C, and at -30°C, their charging capacity is only 14% of the total charging capacity, making them unable to function properly in extremely cold weather.
Furthermore, because lithium titanate batteries exhibit only a 1% volume change even when overcharged, they are known as zero-strain materials, resulting in an extremely long lifespan. Yinlong Chairman Wei Yincang has stated that Yinlong's lithium titanate batteries can last up to 30 years, comparable to the lifespan of a car, while ordinary graphite anode material batteries have an average lifespan of only 3-4 years. From a full lifespan perspective, lithium titanate batteries are also more cost-effective.
The final advantage of lithium titanate is its strong fast charge and discharge capability and high charging rate. Currently, Yinlong's lithium titanate batteries have a charging rate of 10C or even 20C, while batteries using ordinary graphite anode materials only have a charging rate of 2C-4C.
Based on these technical characteristics of lithium titanate batteries, industry insiders believe they meet the needs of new energy buses and large-scale energy storage equipment. Taking buses as an example, a typical single trip is no more than 40 kilometers, and the interval between each stop and the next departure is at least several minutes. In this case, the low energy density of lithium titanate batteries does not affect the bus's operation; on the contrary, it highlights the benefits of fast charging. As public transportation, buses place higher demands on battery safety and durability.
