Battery Technical Info, Battery Usage Tip, Market Trends

Why are so many car companies interested in lithium iron phosphate batteries?

Car batteries

As the “Heart”of the new energy vehicle, the power battery can determine the driving range, safety and other vital properties of a pure electric vehicle . Under the previous policy, the market favored the Nickle Cobalt Managanese battery pack(NCM Battery) due to high energy density.However, since 2020, the installed capacity of the NCM battery cell began to decline and LFP battery pack installed capacity began to rise.

According to figures released by the China Automotive Power Battery Industry Alliance, China power battery sales totaled 65.9 GWH in 2020. Of these, 38.9 GWH(61.1%) NCM batteries were installed, cumulative decline of 4%. While 24.4 GWH (38.3%) of the lithium iron phosphate batteries were installed, cumulative increase of 20.6%, making them the only type of power batteries whose sales increased year on year.

There will also be more models loaded with lithium iron phosphate batteries in 2021, for example: In March, a golf cart factory announced new EV battery models for the G3 and P7, which will be equipped with lithium iron phosphate batteries, Ula also released three lithium iron phosphate versions in mid March. In addition to which, in early March, the Ministry of Industry and Information Technology (MIIT) issued the 342nd batch of “Road vehicle manufacturing enterprises and products announcement”, it release 22 types electric vehicle equipped with LFP b attery pack 72V 100AH LFP battery pack and 144V 200AH battery pack are our hot sell models.

Car batteries

Why are so many car companies interested in lithium iron phosphate batteries than NCM batteries?

lithium iron phosphate costs less, makes it easier to buy

According to a Bloomberg New Energy Watch Survey released in December,the global market for high quality NCM battery cell l is $180 per kWh, compared with $160 per kWh for lithium iron phosphate, a gap of $20.

At the moment, the battery capacity of most pure electric vehicles is 70 kwh. We calculate this capacity (not counting the cost of battery composition) , and the cost of using NCM battery cell is $12,600 (RMB 91,800) , a lithium iron phosphate battery costs just $11,200 (72,800) . The difference is around $1400, and the bigger the future battery, the bigger the difference.

That’s the main reason why the Model 3 Model will cost 249,900 RMB, down from 271,550 RMB, according to the application of LFP battery pack.

lithium iron phosphate, higher safety performance, more durable

The problem of spontaneous combustion of new energy vehicles has been paid much attention, it is understood that there will be more than 50 fire incidents in 2020, most of which are spontaneous combustion. Previously, Liu Peng, Deputy Secretary General of the National Big Data Federation of New Energy Vehicles, said that most of the new energy vehicle safety accidents occurred in a high SOC state, in which the NCM battery pack is more vulnerable to thermal failure because of its high energy density and high activity, decomposition and explosion can occur at temperatures ranging from 250 °C to 300 °C.

The lithium iron phosphate battery will decompose when the temperature exceeds 600 °C, which is more stable than the NCM electric vehicle lithium battery. In addition, the lithium iron phosphate battery can be charged 3,500 times before it decays to 80% of the mandatory replacement limit, which is estimated to last more than 10 years, while the NCM lithium battery has decays to the limit after about 2,000 times, this will only last about six years.

The shortcomings of lithium iron phosphate batteries have been reduced as technology matures

In 2019, the government raised the threshold of the subsidy policy. The energy density of the power battery needed to reach 105 Wh/kg, and the range of the battery needed to reach 250 km before the subsidy could be carried out. However, the technology was not mature enough at that time, low energy density lithium iron phosphate batteries difficult to obtain subsidies, many car companies choose a higher energy density NCM lithium-ion batteries.

But as Chinese battery technology matures, many power battery companies have developed ways to solve the problem of low energy density lithium iron phosphate, like the CTP technology which changes the battery pack’s internal layout structure, remove the module, the core will be directly composed of pack. This increases the volume utilization of the battery pack by 15-20% and the energy density by 10-15% .

electric vehicle lithium battery

In addition, there is another pack technology, the battery through the CTP (Cell to Pack) design ideas, directly removed the battery pack internal frame, through the lateral dense array of multi-row cells, will improve the utilization of internal space to about 60% . The result is an increase in the overall energy density and capacity of the battery pack. The battery pack, for example, has a total energy of 76.9 kwh and an energy density of 140 Wh/kg.

The new CTP design concept not only makes the blade battery in the performance parameters to reach the average level, due to the reduction of the battery assembly module end plate, side plate and used for fixing the module frame, bolts and other fasteners, it also reduces part of the manufacturing cost and improves the manufacturing efficiency.

How to choose between lithium iron phosphate battery and NCM battery?

Although the capacity of lithium iron phosphate battery is increasing, the battery is not completely replacing the NCM lithium battery, many car companies choose to use “Two legs”walk, the same model will release two different battery versions. Many consumers will wonder how to choose between the two versions.

In my opinion, the specific choice or need to be based on the car, we take the XiaoPeng P7 and Ula good cat to example.

The first is the Xiaopeng P7, the lithium iron phosphate version of the starting price has not changed, but in the range and configuration have been adjusted, which range from 586 km down to 480 km, in the configuration with the XPILOT 2.5 system. If you want to experience the current self-driving function and do not require very long driving range, I think the lithium iron phosphate version is more suitable, but if customers often use the new energy car to drive long-distance , a NCM battery is a better choice, since longer battery life can certain reduce range anxiety.

Then there’s Ula, the lithium iron phosphate version, which is identical to the NCM lithium lithium ion version in price, configuration and range. Therefore, for consumers needs to consider their own region when make a decision, although the current lithium iron phosphate car model as an auxiliary temperature control technology BMS, can minimize the problems caused by low temperature on the battery, but in the face of extreme cold or more or less will lead to a certain reduction in battery life, if living in the cold area in winter, I suggest you to choose NCM lithium battery will be more suitable.

At the end

After the improvement of technology, the advantage of lithium iron phosphate battery will be more prominent, from the electric vehicle installed capacity can see the rising development of lithium iron phosphate battery, but this does not mean the decline of NCM lithium battery. From SmartPropel opinion, these two different batteries, like the natural gas intake and turbocharging in the era of fuel cars, have their own advantages and disadvantages, which form a complementary way to cover a wider range of use scenarios and provide more choices for electric vehicle consumers.