LiFePO4 or ternary lithium battery, how to make a better choice between them

Solar Energy

LiFePO4 or ternary lithium battery, how to make a better choice between them

August 25, 2022
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10 mins to read

Which one is better, lithium iron phosphate (LiFePO4) or ternary lithium battery? What is the main difference between LiFePO4 and ternary batteries? Ternary and lithium iron phosphate are two common materials in the lithium battery market now, how can we make a better choice to get a better one?

In fact, Ternary lithium and LiFePO4 batteries have their own characteristics, there is no good or bad in technology, only fit or not fit. The best choice is to choose the right ones. Then which one is more suitable between LiFePO4 and lithium ternary batteries?

Lithium iron phosphate battery is often named as LiFePO4 battery

LiFePO4 battery, which refers to the lithium-ion battery with lithium iron phosphate as the cathode material. This type of battery is characterized by the absence of precious metal elements (such as cobalt, etc.). In actual usage, LiFePO4 batteries have the advantages of high temperature resistance, high safety stability, low price and better cycle performance. The price of raw materials is low, and phosphorus and iron exist in the earth's rich resource content, which means there will be no problems with its supplying.

The advantages of LiFePO4 battery

1. Safer to use.

The P-O bond in the crystal of LiFePO4 is stable and difficult to decompose, even at high temperatures or overcharging, the structure will not collapse and heat up or form strong oxidizing substances like lithium cobaltate, so it has good safety. LiFePO4 battery has undergone rigorous safety testing, puncture will not explode even in a collision.

2. Much longer lifespan.

LiFePO4 battery has a cycle life of more than 2000 times under its standard 100% charging and discharging. It only lasts 1 to 1.5 years for a lead-acid battery. While the cycle life will reach 7 to 8 years for LiFePO4 batteries which works in the same conditions.

3. Better in high temperature resistance.

The thermal peak of LiFePO4 battery can reach 350℃ -500℃, while the lithium manganate and lithium cobalt only in about 200℃. A wide range of operating temperature (-20℃ to -75℃), which is much greater in high temperature resistance.

4. Lighter in weight.

The same capacity of LiFePO4 battery volume is 2/3 of the volume of lead-acid batteries, and weight is only 1/3 of lead-acid batteries.

5. Environmentally friendly.

There is no pollution in the LiFePO4 battery comply with the European RoHS regulations, and it is absolute green battery.

6. Fast in charging.

High-current 2C fast charging and discharging, 1.5C charge in a special charger can be fully charged within 40 minutes, the starting current can reach 2C.

Disadvantages of LiFePO4 battery

1. LiFePO4 cathode vibration density is small, the density is generally in the 0.8 to 1.3 or so.

2. Poor electrical conductivity, slow diffusion of lithium ions, high times when charging and discharging, the actual capacity is low.

3. LiFePO4 batteries are not very good in its low-temperature performance.

Ternary lithium battery

Ternary lithium battery is a lithium battery that uses lithium nickel cobalt manganate (Li(NiCoMn)O2) ternary cathode material for the positive electrode and graphite as the negative electrode material. Ternary lithium battery voltage platform is very high, which means that in the same volume or weight compared with LiFePO4. Ternary lithium battery has greater specific energy, specific power. In addition, the ternary lithium battery also has great advantages in terms of large rate charging, and low temperature resistance.

Advantages of ternary lithium battery

1. High voltage platform.

The higher the voltage platform, the greater the specific capacity. For the same volume, weight, and even the same capacity of the battery, ternary material voltage platform is significantly higher than LiFePO4, its voltage line can reach 4.2 volts, the discharge platform can reach 3.6 or 3.7 volts.

2. High energy density, and high vibrational density.

Ternary lithium battery disadvantages

1. Poor in the safety.

2. Poor in heat resistance.

3. Poor in lifespan.

4. Poor high-power discharge.

5. The element is toxic, ternary lithium batteries high-power charge and discharge after a sharp rise in temperature, high temperature after the release of oxygen is very easy to burn.

The application range of LiFePO4 battery includes data centers, server room systems, communication base stations, emergency power, solar street lighting, EV bus and cars, industrial equipment, medical equipment, energy storage field and so on. The energy storage field will be the largest application of LiFePO4 market. Ternary lithium batteries are more suitable for EV cars.

With its vast size and complex climate, the earth is rich in temperature variations from the northernmost to the southernmost tip. Take for example like Beijing, China, it’s the main market of electric vehicles, the maximum temperature in Beijing in summer is around 40℃, while in winter, it is basically kept around -16℃ or even lower. Such a temperature range is clearly suitable for low temperature performance of ternary lithium batteries. While LiFePO4 batteries runs better on high-temperature performance which seems a little weak in Beijing's winter.

How to evaluate the performance of a power battery

As we all know, lithium-ion battery are composed of four parts: cathode material, anode material, diaphragm and electrolyte, of which the cost of cathode material reaches 30%, which is also the key to enhance battery performance, according to the use of different materials are divided into lithium titanate, lithium cobaltate, lithium manganate, lithium iron phosphate, nickel cobalt manganese and nickel cobalt aluminum six, the latter two of which are the famous ternary lithium batteries, also known as ternary polymer batteries. Industry insiders pointed out that power battery performance indicators are mainly energy storage density, cycle life, charging speed, resistance to high and low temperatures and safety five dimensions, of which energy storage density and safety are the two main needs, lithium titanate and lithium manganate battery because the storage density is too low and was abandoned, lithium cobaltate is too poor safety and put on the shelf, leaving only lithium iron phosphate and ternary lithium batteries among the mainstream market, respectively, used in EV bus market and EV car market.

Ternary lithium battery VS LiFePO4 battery

In fact, we can’t say that ternary lithium and LiFePO4 these two kinds of batteries are absolute good or bad, but have their own characteristics, where the ternary lithium battery has its advantages in the energy storage density and resistance to low temperature.

Firstly, in the energy storage and density, because of the high voltage and its energy density can reach 240WH/kg, ternary lithium battery is almost 1.7 times of LiFePO4's 140WH/kg. At the same time, compared with NCA (nickel-cobalt-aluminum) and NCM (nickel-cobalt-manganese) batteries, NCA performance is more excellent, but because of the lower thermal escape temperature, high requirements for the production process, high costs and technology which are in the control of Japanese and Korean companies, therefore, we mainly develop NCM batteries, which are currently divided into 111, 523, 622 and 811 according to different ratios of ternary materials, of which the 881 high nickel battery has become the key breakthrough direction, because it is the key to enhance the energy density of the cell.

Secondly, the resistance to low temperature. Ternary lithium battery has a limit of -30℃, but the LiFePO4 is -20℃, more advantageous, while in the same low-temperature conditions, the ternary lithium battery winter attenuation is less than 15%, which is significantly higher than the LiFePO4 attenuation of up to 30%, more suitable for the northern market. That is why BYD sells well in the south, but it is difficult to open the market in the north.

However, LiFePO4 also has advantages in 3 aspects

First, LiFePO4 battery is higher in safety. Because LiFePO4 battery thermal runaway leads to failure temperature is generally more than 500 degrees, ternary lithium batteries are less than 300 degrees, some high nickel battery thermal runaway temperature is even less than 200 degrees, and the risk of spontaneous combustion of LiFePO4 in the process of high-speed car driving and rapid charging is low.

Second, LiFePO4 battery has a much longer lifespan. Because LiFePO4 charge/discharge cycles greater than 3500 times before it begins to decay, which means that its service life of about 10 years, but the number of charge/discharge cycles of ternary lithium batteries is only 1000 times, meaning that its service life is only 3 years, so the difference between their lifespans are really big.

Third, LiFePO4 battery’s manufacturing cost is lower. There are no precious metals in LiFePO4 battery, therefore its production costs are much lower. In contrast, ternary lithium batteries need cobalt metal, 70% of its reserves are in the Congo, Africa, which makes its import prices have soared, the current price has reached 200,000 yuan/ton, compared to an electrolytic nickel price of only 110,000 yuan/ton, which is the battery companies are forced to take LiFePO4 Lithium iron phosphate route is another key reason.

LiFePo4 battery is an ideal choice for solar lighting industry

There is currently no single solution that is better than another for all situations, but LiFePO4 battery systems offer better cost of ownership in a few situations, specifically hot climates, despite the higher initial cost. Together with its features of safer to use, much longer lifespan, lighter in weight, environmentally friendly and fast in charging etc., LiFePO4 battery has been already the best choice for solar street lighting industry, and it is helping the solar lights to be lasting longer, working safer and most importantly environmentally friendly to our nature.