LFP longevity not panning out in the real world?

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In theory, LFP batteries should last for many more cycles than NMC, giving them a longer life.

However, I am increasingly hearing that this isn't always true in practice and I am curious if anyone has any more evidence on this.

The reasons put forward why LFP doesn't do as well in the real world compared to NMC:
  • Manufacturers use LFP batteries as a low-cost option with little or no "buffers" whereas NMC typically have significant upper and lower buffers (as much as 7-10%) to protect against degradation. So while LFP commonly drops to the low 90%ish range after 2-3 years, NMC can still be at 100% (just with smaller buffers).

  • NMC is typically charged to 80% most of the time, limiting the damage from high states of charge. LFP is typically charged to 100%, something it can tolerate much better, but which still causes some degredation (people do not typically know this), particularly when left at 100% for a long period of time.

  • NMC tolerates high discharge and charge rates much better, so even with the higher charge speeds possible with NMC, less damage may be done through lots of public charging.

  • LFP performs relatively poorly in cold weather, with more dramatic range drops than NMC, affecting real world range in colder climates.

  • Battery aging effects are more dominant than was expected for all types of chemistry, so the benefits are less than were predicted.

  • NMC real world ranges have held up better than all the predictions.

This is how the argument goes as I have heard it.

I accept that chemistry doesn't really matter that much and all battery types are good enough for most people. We will no doubt look back in a few years time and laugh at ourselves for being concerned with it, like debates on the type of oil we used to put in an ICE engine.

But I am curious nonetheless about how theory is translating into practice. All views welcome but particularly anyone with evidence to back them up.
 
My view is that you’re right, it’s unknown. My solution? A bet each way. My wife drives a LFP MG ZS EV and I have the NMC MG4. She always charges to 100%, I stop at 85% but often go higher for long trips. We may never see enough degradation to answer the point before we upgrade. I’ll let you know in a few years. We have often run our vehicles for 300k km (185k mikes) and both do high miles each year.
 
It is quite interesting. But as already been said, who knows. 🤷‍♂️ To be honest, I'm gonna charge me car, when I want and how I want. Not really bothered, how they tell you, it's supposed to be charged. Think they are guessing half the time.
That's my way of thinking anyway. 🙂👍
 
Far too many folk (influencers..) on the internet who just talk sh*** and expect folk to believe it. With batteries especially, not just EV but all batteries, misinformation just propagates and you cannot stop it.

e.g. the nonsense about batteries suffering from a 'memory effect' where if you only ever charge to ~80% they will come to think they are full at 80%. I've seen youtubers and others say that all kinds of lithium batteries suffer from it and it's just not true.
Way back, way way back when Nickle Cadmium batteries were a thing, THEY had that problem but no batteries since have had it. But then some talking head with followers says it's so and suddenly it's all round the globe.

Understandably there's a fair bit of worry about how you treat an EV battery, it's a darned expensive item after all. We're getting to the point now where we can see that the worry is not warranted and as long as you don't regularly mistreat yours it will last way past the lifetime of the car.
 
I saw a well evidenced report saying batteries are doing much better than expected - they think because the expectation is base don lab tests where the battery is continually charged up and discharged and that in the real world batteries spend more time sitting cold and not charging or discharging! I think most people don't charge their LFPO to 100% every day - they just don't need to so they leave it until it has run down a fair way unless they are off on a long trip. It has certainly been how we've charged. And I've seen a road test video of the LFP which achieved 27 miles after reaching zero% suggesting there is a buffer even on the LFP.. Most of what goes around is put out there by big oil to scare us. You just plug it in like your phone and it works.
 
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