2021 TESLA MODEL 3 SR+ LFP BATTERY: Upgrade or Downgrade?
In China and in EUROPE, a LITHIUM IRON PHOSPHATE battery pack is standard for the lowest range variant of the Model 3, however the Standard Range Plus Model 3’s sold in NORTH AMERICA normally contain a Nickel-Cobalt-Aluminum battery pack. However, a few weeks ago, tesla contacted a number of Model 3 SR+ reservation holders and offering them a NEW variant of the SR+ with slightly less range and a LITHIUM IRON PHOSPHATE battery pack.
Unfortunately, there were only a limited number of these Standard Range Plus Model 3’s with the LFP battery packs available and the supply appears to be sold out. However, I do believe that Tesla was simply testing the waters in the North American market, and that they will soon offer this Lithium Iron Phosphate battery pack as standard in teh North American Standard Range Plus Model 3.
Here are a few of the benefits of a Lithium Iron Phosphate battery pack.
SAFETY:
While Tesla has had a very good track record for BATTERY safety, and their NCA packs are much less likely to catch fire than an internal combustion engine, Lithium Iron Phosphate batteries are considered EXTREMELY safe, do not tend to overheat and are not prone to thermal runaway!
MORE USABLE RANGE:
As Elon mentioned, LITIUM IRON PHOSPHATE batteries like to be charged to 100% (and from what I can tell actually need to be charged to 100% at least once a week to keep the range estimates accurate), and can be done safely without battery life degradation. In contrast NCA (Nickel, Cobalt, Aluminum) battery cells can suffer increased degradation in repeatedly charged to 100% - it is recommended to charge them up to 80% or 90% on a regular basis, and only to 100% for longer trips (or to occasionally reset the estimated range calculation accuracy).
This means that a 263 mi SR+ charged to 90% will give to around 237 miles of range – which is around 16 miles less than a 253 mi SR+ charged to 100%. So, in daily – real world use, the LFP battery actually has an advantage!
LONGER LIFE:
According to a 2019 tweet from Elon Musk, the 2170 battery cells (NCA chemistry) found in the existing Model 3s made at Fremont are expected to last around 1,500 cycles which translates out to somewhere between 300K to 500k miles of use. While this is plenty of battery life, CATL has developed some LFP battery cells that they claim could be good for over 1 million miles of use!
Whether or not these LFP packs that Tesla is putting the NEW version of the MODEL 3s is designed to last 1 million miles, likely the LFP cells found in the NEW MODEL SR+ variant will have a longer cycle life.
CHARGING SPEED
LFP batteries naturally have lower internal resistance so with the right BMS system, they should be able to sustain a slightly higher rate of power (kW) longer into the charge curve - thus leading to a faster charge. This was demonstrated in a Bjorn Nyland side by side charging test that he performed in June of this year, and he found that the NEW LFP battery does charge a little bit faster than the NCA version and is able to maintain a higher rate of power during the charging cycle.
There are a few potential downside as well that should be mentioned.
POOR COLD WEATHER PERFORMANCE:
The LFP chemistry does seem to be a little more susceptible to cold weather issues – in fact, the first MODEL 3’s with the LFP packs delivered in China and in Europe, suffered from COLD WEATHER performance issues – slow charge rates.
However, recent software updates have fixed many of the cold weather issues with the LFP cells by maintaining a higher battery temperature based on some initial tests from the GERMAN YouTube channel NEXTMOVE.
NOMINAL VOLTAGE
From what I have read, it is more difficult to calculate an accurate amount of battery charge left in an LFP battery cell, because there is less of a voltage fluctuation from a fully charged battery to nearly depleted battery. The car’s software uses this fluctuation in voltage along the charge and discharge curve to help determine how much charge is remaining in the battery – and this lower amount of fluctuation makes these calculations more difficult. Because of this, it is necessary to charge the battery fully to 100% regular (minimum one a week) in order to keep the estimates accurate. This is not a HUGE downside – but it is something to be aware of.
Let me know what you think. Did I miss any benefits or downsides? Which version would you rather have?
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Data Sources:
Million Mile Battery: https://www.greencarreports.com/news/1128429_battery-giant-catl-million-mile-batteries-tesla
BJORN Changing test: https://www.youtube.com/watch?v=S8XiDEFH1q4
Nextmove Charging Test: https://www.youtube.com/watch?v=hTXxfuSDv6c
https://insideevs.com/news/490909/tesla-update-solves-lfp-model-3-issues/
https://insideevs.com/news/514857/mic-tesla-model3-srp-charging/
https://www.torquenews.com/1/tesla-model-3-lfp-battery-has-cold-problem