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Comment by maeln | Hacker News Reader

We should always take marketing number with a huge grain of salt, so the 10 to 98% in 7 minutes remain to be seen. Also, there is the question of if it lowers the battery lifespan faster than charging at lower power. It is does, there might still be a point in battery swap, especially for public transport systems (for bus). A public transit operator might want to have more battery than vehicle, so that they can rotate the battery regularly and charge them at lower power, to diminish and distribute the wear on battery. But that's obviously a big if and a more niche usage.

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> there might still be a point in battery swap, especially for public transport systems

There isn't. Buses aren't really size- or weight-constricted and don't drive at highway speeds, so building one with enough battery capacity to last most of the day isn't a big deal. Plenty of cities have already transitioned to a 100% electric bus fleet, after all.

A big thing to remember is that people don't travel at the same volume at every moment of the day, so you don't need to run buses at the same frequency the entire day either. You can run buses at 10-minute intervals during commute hours, 15-minute intervals in the middle of the day, and 30-minute intervals in the early mornings and late evenings. This means that there is plenty of time between the morning rush and the evening rush for some buses to go off-duty and charge for a few hour. They are going to sit idle anyways, so why not make use of it?

There are many cases where the EV busses have been abandoned. Busses typically do not do their route and stop, so getting a significant amount of charging for any busses requires extra busses that can be rotated on/off duty. If you design the system to depend on that charging then you need extra busses and you're effectively stuck with a sparse schedule. That is not a constraint to consider with petrol-powered busses. They can run nonstop as much as needed.

There is another thing cities should consider in all this: EV busses are totally unsuitable in emergencies. They cannot be charged fast enough, especially in extreme weather. You should consider this before buying an EV as well. At least, have a plan to arrange alternate transport with a reliable petrol vehicle.

> There are many cases where the EV busses have been abandoned

Source?

> Busses typically do not do their route and stop, so getting a significant amount of charging for any busses requires extra busses that can be rotated on/off duty.

Yes. But like I said: this was already the case with diesel buses. Nothing changes here. The duty rotation is demand-driven, not supply-driven.

> EV busses are totally unsuitable in emergencies.

Emergencies are the exception, and there are very few cases where regular city buses (of any kind) are going to be the backbone of a last-minute evacuation plan. And even in that case: usually you only need to drive a dozen miles / kilometers to get out of immediate danger - which should be perfectly doable.

> You should consider this before buying an EV as well.

I completely agree. Leaving a few dozen miles / kilometers of range in the battery not only is a sensible preparation for any kind of (natural or personal) emergency, but it is also better from a charging speed and battery longevity perspective.

the life span stat with the current battery tech is mostly useless for a normal car. 300 mile range most people will need to top up 2 times a week 100 times a year 1000 times in 10 years. The battery degradation is not that bad in the first place.

> most people will need to top up 2 times a week 100 times a year 1000 times in 10 years.

When it comes to as-fast-as-possible charging, I think you can divide that number by at least 10. Slow charging while parked overnight or during the day should still be the most common case by far for most users. Very fast charging is important for road trips, but it is not the usual case.

First, with range decreasing, number of charge cycles per mile, and therefore rate of wear, will increase.

Second, average age of car on the road is above 10 years in most countries; and those that drive old cars definitely do not have €26,500* spare to swap their EV's battery for a new one.

*That's what Audi charges here for e-tron 50 battery replacement, which are already starting to fail for many owners

Western car manufactures scamming their customer should not be what you look at for costs. Batteries pack costs have gone from $130-150/kwh in 2023 $80-90/kwh in 2026. Price for a pack will likely be under $50/kwh in another 3-4 years. Ie battery packs are becoming competitive with engines already and will be cheaper by 30-40% ie replacing a battery will be cheaper than replacing an engine/

No car manufacturer actually sells battery packs for $80-90/kWh or anywhere near that. That's what it costs THEM, not service customers.

> First, with range decreasing, number of charge cycles per mile, and therefore rate of wear, will increase.

By 10% over 10 years, assuming the worst case of nothing but ultra-fast charging. This seems minor.

Old cheaper cars could be 10% less convenient to use for very long trips. This should not shock anyone.

Rather than an expensive battery swap, sell it on at a lower price to someone who doesn't need 100% range.

That's a theoretical / marketing number. In real life I am yet to see meet an EV owner who reports >80% of range after 5 years / 100 000 km of mostly-at-home charging. I see those on internet forums, but on internet forums, anyone can write anything, so I do not take those reports too seriously.

From my personal family anecdotes: my mothers' 4 year old Hyundai Ioniq 5 had complete battery failure. Thankfully under warranty. And my fathers' 5 year old Audi e-tron 50 already has <80% range remaining, with very rare fast charging.

> Also, there is the question of if it lowers the battery lifespan faster than charging at lower power.

This kind of fast-as-possible charging rather than overnight or "while parked at the mall for hours" slow charging should be the exception rather than the rule, i.e. it is useful when road-tripping long-distance, but is not not the daily case. Battery lifespan should not be based on assuming that it's the only thing that you ever do.

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