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Comment by eikenberry | Hacker News Reader

What part of EVs is "rapidly advancing technologically"? The battery is the only thing that comes to mind and they should be replaceable if that was the bottleneck. Self-driving is also advancing, but that hasn't stabilized as a feature yet. EV motors have been around for a long time and the rest seems like general car stuff that would be common with ICEs.

Following that logic it seems to come down to old batteries which aren't as good both due to technological advances and battery aging. If so, why aren't used dealers just including a battery swap in the price?

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> If so, why aren't used dealers just including a battery swap in the price?

I think that is the main thing that needs to be figured out. I suspect the problem is that you need to get OEM battery replacements for older model cars and those aren't yet readily available or cheap. We are going to need aftermarket batteries to drive price competition in the market. The current car manufacturers aren't incentivised to support a secondary market when they are still focused on primary sales. Also not in the ICE market there is much more ability to scale capacity. The supply chain constraints for EVs, and batteries are much tighter, though that keeps getting better.

Battery swaps are never going to be a thing long term, even with Nio rolling it out in areas. It adds huge amounts of weight and complexity. You have to build electrical and coolant connectors which can handle large amounts of connects and disconnects, in areas that get mucky and interact with rain, salt, snow and ice. You have to build a chassis strong enough to take an impact but also support the additional weight and space that a removable battery takes up - think of how much bigger phones with removable batteries.

I have done 900 mile road trips in EVs with 150Kw charging (low by standards of newer EVs) and charging has been a complete non problem. In fact I have more problems with plugging my car in, going to the toilet and coming back finding that I've put more power into the car than I wanted.

Batteries are lasting 200k+ miles with 85-90% original capacity in so longevity is not a problem and charging is becoming a solved problems in an increasingly large portion of the world too.

You put this in the wrong place. "Battery swap" in this context should be read like "transmission swap". Hours of work replacing a permanent part. Nothing to do with detachable batteries.

Hybrids keep their value remarkably well. If each engine isn't spinning half the time they will obviously last longer. They could have a small enough battery that make hot swapping a lot more realistic.

Why not just have more rapid charging and do away with the ICE engine and small hybrid battery altogether.

> "What part of EVs is "rapidly advancing technologically"?"

Battery capacity, motor efficiency (getting more range out of the same battery), charging rate (800V architectures for example that let you charge > 150kW), battery chemistry (wider operating temp envelope, affects charging and driving efficiency depending on environment)... the list goes on.

The batteries are also getting cheaper - which is to say for the same $ you're now (generally) getting a larger battery.

> "If so, why aren't used dealers just including a battery swap in the price?"

Because the batteries are in fact not swappable from one gen to the next, because the power electronics around them are different, peak current draw is different (and that depends on the motor it's mated with!).

Like I know it's tempting and attractive to imagine EVs like regular cars with some giant-ass AA batteries installed on them, but that's not how they work! The battery is specced as a unit with the entire electrical system and drive motor options!

The battery electronics aren't necessarily all that complicated:

https://www.youtube.com/watch?v=sZHN3fjDtpc

The precharge resistor has to be reasonably matched with the devices connected to the battery though.

And of course there could be additional converting electronics for charging or whatever.

If you look at EPA efficiency in 2020 and 2025, it hasn’t really moved that much for the same class of vehicle.

> Like I know it's tempting and attractive to imagine EVs like regular cars with some giant-ass AA batteries installed on them, but that's not how they work!

Come on, we all know the big Christmas toys would always use those fat C batteries that we never had enough of.

Batteries need to be split into several replaceable modules, so the entire car isn't a write-off if there's a fault or damage affecting the battery

Ideally, these battery modules would be standardised and used across a wide range of vehicles.

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