During a talk about Tesla, my friend asked if the 2016 Model S I might buy has LFP or lithium-ion batteries. I didn’t know what LFP meant, so I searched online. I found out that LFP stands for lithium iron phosphate. One thing I learned is that LFP batteries can be charged up to 100% without damaging them, unlike lithium-ion batteries which shouldn’t be fully charged unless necessary.
I wonder if this is true. Also, if LFP batteries degrade less, what are their downsides? I know lithium-ion batteries are very common, and Tesla has started using them too. I just want to understand the science behind it a bit more.
LFP is lithium-ion. When you say Li-ion, you probably mean NMC. Yes, LFP degrades a lot less than other lithium chemistries, and you can charge them daily to 100%, while you shouldn’t with most other types. The drawbacks of LFP are lower energy density (heavier batteries) and poorer performance in very cold conditions. However, they are better in terms of being cheaper, safer, and longer-lasting. As for Tesla, only the Model 3 Standard Range has LFP, as far as I know. Definitely not the S, and not a 2016 S, since they started using LFP only 2 or 3 (or maybe 4) years ago.
LiFePO4 batteries surpass comparable lithium-ion batteries in many aspects. They exhibit reduced susceptibility to combustion and thermal runaway, enhancing safety, particularly for domestic applications. Additionally, their extended cycle life ensures that LiFePO4 batteries outlive lithium-ion counterparts by up to five times.
Tesla began equipping their standard-range Model 3 vehicles with LFP batteries in late 2021. To my knowledge, no other Tesla models have used LFP batteries.
The reason behind this decision is that the standard-range Model 3 was always designed to use the same physical battery pack as the long-range version, which contains significantly more battery cells. As a result, the standard-range pack had a lot of unused space. Tesla utilized this empty space by adding the extra cells needed to compensate for the lower energy density of LFP batteries. In contrast, the long-range vehicles do not have this available space in their packs, so they continue to use NMC chemistries.
These batteries are indeed known for their ability to be charged up to 100% without significant degradation, which is one of their advantages over traditional lithium-ion batteries.
LFP batteries, compared to standard lithium-ion batteries, offer superior safety, a longer lifespan, and excellent thermal stability. The chemistry of LFP batteries is such that they are less prone to overheating and thermal runaway, which are risks associated with lithium-ion batteries.
However, LFP batteries do have some downsides:
They have a lower energy density than lithium-ion batteries, which means they can store less energy per unit of volume or weight.
This can translate into a shorter range for electric vehicles or a larger battery size for the same range.
They also have a lower voltage per cell, which can affect the power output and efficiency in some applications.
Lithium iron phosphate (LFP) batteries stand out from traditional lithium-ion ones with their robustness and longevity. The 2016 Tesla Model S, however, is equipped with lithium-ion cells that have a different chemistry. LFP batteries can safely charge to full capacity, avoiding the degradation that often plagues other lithium-ion batteries. They last longer due to their stable makeup but trade-off with lower energy density, meaning they hold less power relative to their size. They also operate at lower voltages and may not perform as well in the cold. Understanding these nuances can guide your decisions regarding electric vehicles and their batteries.