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Ancient_Persimmon t1_ja0rt9a wrote

LFP chemistry has been evolving pretty quickly, but generally speaking, they charge slower than a Nickel based pack.

One large enough for an F-series should be able to beat the current Lightning's 150kW rate though.

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sbradford26 t1_ja1fx0e wrote

So the individual cells may have a slower max charge rate but I believe LFP generates less heat so at a pack level they most likely can hit higher charge rates without hitting thermal limits.

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[deleted] t1_ja3l1of wrote

[removed]

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sbradford26 t1_ja3vfsz wrote

So the energy density at the cell is lower, but due to better thermal performance you can get similar pack level energy density.

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mikasjoman t1_ja3rm84 wrote

Dude, that's not the chemistry being discussed.

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sbradford26 t1_ja3uqqr wrote

LiFePo4 and LFP are the same just different abbreviations.

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Steakosaurus t1_ja1o0cs wrote

LFP struggles with range and cold weather performance. The energy density of the chemistry is very poor compared to high nickel based chemistries, and leads to very heavy and expensive packs to meet range targets (more cells to hit the same energy).

It's primary advantages are in it's comparatively better thermal propagation performance and in cost - although the need for additional cells to meet range and the piss-poor recycling economics (LFP costs more to recycle than it's individual components are worth) eat into this financial advantage.

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Black_Moons t1_ja1ux3i wrote

Lifepo4 have amazing life though. Iv got a 15 year old pack still at 50%+ capacity.

I mean, 50% sucks, but most other packs would be refusing to charge by now, or sagging too much to run the load. Means 5 year old 2nd hand trucks might be usable without a new battery if the owner doesn't need more then 75% range.

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Ok-Welder-4816 t1_ja1zj7u wrote

The essentially infinite recycling potential of nickel packs is better for the planet, though. And since they can be recycled easily, you should be able to get more money for a dead pack.

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Okiekid1870 t1_ja1zrxk wrote

Currently battery is warrantied to 70% for 8yr or 100k mikes.

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Steakosaurus t1_ja2xheh wrote

> Iv got a 15 year old pack still at 50%+ capacity.

That may be a selling point for a small niche of drivers, but telling someone that their vehicle will degrade to roughly half the already low range is going to be a hard sell.

LFP struggles to hit something like 300 miles in very large packs, degrading to ~150 miles in a few years and having further reduced performance when it's cold out is a really hard sell.

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bigmark14 t1_ja3gx50 wrote

15 years is not a few years

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Steakosaurus t1_ja3rr7x wrote

The battery did not degrade to 50% capacity in 15 years, unless it was barely used and babied for the entirety of that time.

Capacity degradation happens over the life of the cell and you can see substantial loss in 3-5 years of normal use.

So when you're starting with a chemistry that's already poor on range, and then reducing that range by 20-30% within the first 5 years of it's life, you can see where customers would be unhappy with the performance.

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Muvlon t1_ja39sdf wrote

Another benefit is safety - LFP batteries do not react nearly as catastrophically to overcharging, overheating and physical impact as NCA or NMC.

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Steakosaurus t1_ja3sm26 wrote

Yeah and those are really functions of the energy density of the chemistry.

I would argue that things like overcharge and impact/crush are less of a concern as we move forward, since overcharge has been largely made a nonfactor by more sophisticated charging software and impact is largely addressed with proper pack design, but LFP definitely remains an attractive option from the safety point of view.

Primarily, the relatively good thermal prop performance is what many are interested in. High nickel chemistries have a lot of latent energy and volatile electrolytes that make battery fires aggressive and dangerous. LFP, having far lower latent energy, is much less prone to a runaway reaction - in which the becomes hot enough to self perpetuate an ignition burning through it's electrolyte and active material - which means it's far less likely to propagate to nearby cells and cause a chain reaction that we see as a massive EV car fire.

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weaselmaster t1_ja1muzz wrote

Wait - nickel? Like nickel cadmium? Isn’t that shit toxic?

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Steakosaurus t1_ja1n4se wrote

Nickel, like Nickel-Cobalt-Aluminum (NCA) or Nickel-Cobalt-Manganese (NCM).

It's shorthand for the cathode chemistry.

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