Tesla Switches Battery Chemistry

Tesla Switches Battery Chemistry

Tesla is switching to a lithium-iron-phosphate (LFP) cathode battery chemistry in all of its standard-range electric vehicles, according to the automaker's third-quarter investor deck.

The move is most likely a strategy for Tesla to boost profit margins on its fully electric vehicles without having to hike prices. Tesla has been chastised in the past for its erratic vehicle pricing. At its Shanghai factory, the company is already producing automobiles with LFP chemistry. China, the Asia-Pacific region, and Europe are among the countries where it sells those vehicles.

According to materials researcher and consultant Roskill, China generally encourages the usage of this sort of battery. Around 95% of LFP cathode manufacture is done in China.

Tesla asked Model 3 reservation holders in the United States in September if they would accept a car with a battery produced using LFP cells rather than the Nickel Cobalt Aluminum Oxide (NCA) cells used in previous Model 3 sedans sold in North America.

Several manufacturers like as Ford Motor and Volkswagen have expressed interest in the battery chemistry for lower-cost models. It's also appealing for business cars such as delivery trucks that don't require a multi-hundred-mile range.

CATL and BYD are the two leading manufacturers of these battery cells. According to prior reports, Tesla is already buying batteries from CATL. Tesla make the announcement in its investor deck saying it is “shifting to Lithium Iron Phosphate (LFP) battery chemistry globally.”

What are Lithium iron phosphate batteries?

Lithium iron phosphate (LiFePO4 or "LFP" for short) is a chemical compound. LFP is one of the safest and most stable cathode materials available for lithium-ion batteries, with good electrochemical performance and low resistance.

Lithium iron phosphate batteries are a form of lithium-ion battery that stores lithium ions using lithium iron phosphate as the cathode material. Graphite is commonly used as the anode material in LFP batteries. LFP batteries have a high current rating, good thermal stability, and a long lifecycle due to its chemical makeup.

Four battery cells are connected in series in most lithium iron phosphate batteries. An LFP battery cell has a nominal voltage of 3.2 volts. When four LFP battery cells are connected in series, a 12-volt battery is created, which is an effective replacement for many 12-volt lead-acid batteries.

Different types of lithium-ion batteries are created by changing the chemical substance used in the cathode. Each of these battery types has its own set of strengths and drawbacks, making them suitable for a variety of applications. We can see where lithium iron phosphate batteries stand and which applications they are suited for by looking at their major qualities.

Among other lithium-ion kinds, LFP batteries have one of the highest specific power ratings. In other words, LFP batteries with high specific power can deliver large amounts of current and power without overheating.

On the other hand, keep in mind that LFP batteries have one of the lowest specific energy ratings of any battery type. LFP batteries have a lower specific energy than other lithium-ion choices, which implies they have less energy storage capacity per weight. This is usually not a problem because the capacity of the battery bank can be increased by connecting more batteries in series. This may not be good for applications requiring high energy density in a small size, such as battery electric vehicles.

The life duration of lithium iron phosphate batteries starts at around 2,000 full discharge cycles and grows depending on the depth of discharge.

The discharge rate is expressed as a multiple of the battery's capacity, therefore a 1C discharge rate for a 100Ah battery equates to 100A continuous discharge. Commercially available LFP batteries typically have a 1C continuous discharge rating, however depending on the battery management system, this can be exceeded for brief periods of time.


Safety Advantages

LFP batteries are one of the most stable lithium-ion chemistries available. Because of their stability, they are one of the safest choices for both consumer and industrial uses. Lithium titanate is the only other comparable safe choice, however it is often cost prohibitive and does not work at the necessary voltage in most scenarios for a 12V replacement.