Tesla, BYD have to get involved, lithium iron phosphate battery advantages? Why will "return"

Remember when the domestic new energy market first emerged, the industry is filled with a large number of pure electric vehicles using lithium iron phosphate batteries. In recent years, along with the new energy market continues to upgrade and change, once represented the "low-end" lithium iron phosphate battery seems to be gradually forgotten, ternary lithium batteries are more car companies and consumers favor, become the mainstream of the market.

However, some time ago, the domestic Tesla Model 3 confirmed the use of lithium iron phosphate batteries and BYD's "Blade Battery" appeared, which made the lithium iron phosphate batteries back to the consumer's field of vision. So, is the use of "low-end" lithium iron phosphate battery technology "regression"? What are the advantages and disadvantages of this technology? Why would it choose to "return" at the present time node? With these questions, the surfer today and everyone to talk about.

In the field of power battery, ternary lithium and lithium iron phosphate are two commonly used lithium-ion batteries. Ternary lithium batteries for the cathode material using lithium nickel cobalt manganese acid or lithium nickel cobalt aluminum acid and other ternary polymer lithium-ion secondary batteries, while lithium iron phosphate batteries because of the cathode material for the lithium iron phosphate and named. "Ternary" contains a precious metal - cobalt, since 2017, the global price of cobalt material has continued to soar, the price of ternary lithium batteries has also risen. In contrast, lithium iron phosphate batteries will be simpler to manufacture, the cost of materials used is also lower, does not contain nickel, manganese, aluminum, cobalt, such as price fluctuations in the metal elements, its manufacturing cost compared to the ternary lithium batteries is about 20% lower.

According to the data of true lithium research, as of the end of 2019, the unit price of domestic ternary lithium battery packs is 1.05 yuan / Wh; lithium iron phosphate battery packs are 0.8 yuan / Wh. Tesla will use lithium iron phosphate batteries in the domestic Model 3 as well as in many future models after reaching an agreement with Ningde Times, and all these can effectively reduce costs. Compared with the status quo, Tesla will reduce the cost by at least 10% after replacing the lithium iron phosphate battery. In this way, not only the localization process of parts can be accelerated, but also with the price reduction will help Tesla to seize more market share.

In addition to the cheap cost, lithium iron phosphate batteries also have good stability and high security features. The electrochemical performance of the cathode material of lithium iron phosphate batteries is relatively stable, and the structure of the battery will not change during the charging and discharging process. Characteristically, it is more secure than the ternary lithium batteries, even in short circuit, extrusion, puncture and other special conditions, is still not easy to explode. This point from the previous period, BYD "blade battery" safety test can also be seen.

It is reported, lithium iron phosphate battery thermal runaway temperature is generally more than 500 ℃, ternary lithium battery is less than 300 ℃, some high nickel ratio of ternary lithium battery thermal runaway temperature is even less than 200 ℃. In addition, because it does not contain heavy metals and rare metals, lithium iron phosphate battery will be relatively environmentally friendly, but also more conducive to recycling. So in the early years, after the comprehensive cost, technology and other factors, lithium iron phosphate battery will become a new energy vehicle ride preferred.

Looking at it this way, lithium iron phosphate batteries seem to be a "good quality and cheap" choice, so why the "silence" for so long?

After experiencing the "subsidy fraud" and uneven product quality of the new energy development of the initial stage, the state subsidies will be more and more biased in favor of long range, high energy density of the battery system models; for the average consumer, a longer range, often also can bring more comfortable car experience. As a result, automakers have been moving their products in the direction of "high range".

But the lower energy density and the difficulty in improving range is the biggest "disadvantage" of lithium iron phosphate batteries. The lithium ternary battery has gradually become the mainstream of the industry with its high energy density and longer range. Although the use of ternary lithium batteries, the cost will increase a lot, but the intuitive range improvement, user mileage anxiety reduction, coupled with policy subsidies and support, ternary lithium batteries will undoubtedly be a better choice. In addition, through the optimization of material modification, surface coating and adjustment of electrolyte and other initiatives, security can also be a good guarantee.

With the subsidies for new energy vehicles at the end of June 2019, the cost has become one of the primary factors for EV companies to consider. The gradual decline of subsidies, and then completely disappeared, seems to be only a matter of time. In this way, car companies in order to maintain the competitiveness of the products of the models, the choice of power batteries, cost and revenue considerations will need to return to "rational", the relatively low cost of lithium iron phosphate batteries and "return" to the vision of car companies and consumers.

At the same time, along with the continuous development of technology, lithium iron phosphate batteries used to be "poor range" disadvantage has gradually been improved. A few years ago, the energy density of lithium iron phosphate battery cells on the market in the 120-140Wh/kg or so, the energy density of the battery system after sealing the package in the 90-100Wh/kg or so. On the contrary, ternary lithium battery, Tesla 21700 battery cell energy density of up to 300Wh/kg. and in recent years, BYD, Lixin, Guoxuan and other battery manufacturers to discuss the production of lithium iron phosphate battery cell single energy density has been able to reach 190Wh/kg, and is expected to reach 220Wh/kg.

And the recent hot BYD "Blade battery" is actually a battery technology called CTP (Cell To Pack), that is, the cell directly into the pack. Due to the flattening of the core, multiple monomer "blade" cells are arranged together in an array, and the length can reach 2500mm; the reorganization efficiency of the core has been greatly improved, and the volume and energy density has been increased by 50% compared with traditional lithium iron phosphate batteries, and the whole life of the vehicle can reach more than one million kilometers. BYD Han EV, for example, the energy density of its battery system reached 140Wh/kg, NEDC standard range of up to 605km; compared with a number of models using ternary lithium batteries, its range is not at all inferior.

Taking a similar route is also Ningde Times, at the end of 2019 Ningde Times and BAIC New Energy released the CTP battery pack. Ningde Times' CTP technology allows battery pack volume utilization to be increased by 15-20 percent, production efficiency to be increased by 50 percent, the number of battery pack parts to be reduced by 40 percent, and system energy density to be increased by 10-15 percent, up to a maximum of more than 200Wh/kg.

At the same time, along with the growing maturity of the new energy market, in addition to the need for Tesla Model 3 and BYD Han EV, such as relatively "high-end" models, moderate range, cost-effective electric mobility scooter will become the market's new demand. In this regard, the long cycle life and lower cost of lithium iron phosphate batteries are more suitable for this type of vehicle than lithium ternary batteries.

After reading the above text, many people may have questions: Is it accompanied by technological development, lithium iron phosphate batteries will become the market "mainstream" again? Will it form a competitive situation with lithium ternary batteries?

While the current method of reducing the weight of the battery pack and improving the overall energy density of the battery pack, so that lithium iron phosphate batteries can compete with lithium ternary batteries, but lithium iron phosphate batteries ultimately have limitations in terms of materials; the energy density of its battery cell monomer is difficult to leapfrog the development of the energy density of the ternary lithium batteries have a greater breakthrough space. In short, ternary lithium batteries have a significant increase in the range of the possibility of lithium iron phosphate battery will appear more difficult.

In addition, lithium iron phosphate battery resistance to low temperatures is also much worse than the three yuan lithium battery. According to experiments, in -20 ℃ environment, lithium iron phosphate battery capacity will have nearly 50% shrinkage, three yuan lithium battery capacity will shrink to 75%. At the same time, the ability of lithium iron phosphate fast charging is not as good as ternary lithium batteries. Comprehensive, lithium iron phosphate battery will be in the low-end products gradually "return". But on the contrary, if the pursuit of more use scenarios (cold and fast charging) and stronger performance, lithium ternary batteries in the future will still be relatively mainstream application technology.

I believe that after reading the above text, we all have a certain degree of understanding of the lithium iron phosphate battery "return". Its return and the improvement of packet technology are the embodiment of the market's gradual rationalization. Accompanied by the acceleration of subsidies and the intensification of market competition, I believe there will be more new technologies. Such as fuel cells, all-solid-state batteries and quaternary lithium batteries, etc., all make surfer full of expectations. Finally, as a consumer, what do you want to say about the "return" of lithium iron phosphate battery? Welcome to interact with us in the following message.

This article comes from the author of the automobile home car, does not represent the views of the automobile home position.