I used to think the same, but I'm starting to disagree.

Batteries aren't as "fungible" as something like gas or electricity is. (is that the right word to use for this?)

You can be reasonably sure that gas is gas, and electricity is electricity, but not all batteries are going to be the same. Some will be higher capacity, some will have greater life, some will be heavier or lighter, some cars or trucks will need bigger or smaller batteries, etc... Some could even be damaged and unsafe, which is something you don't really get with gas (sure bad gas could ruin your car, but gas from a pump isn't going to catch fire randomly and hurt you because it's bad)

At the end of the day, it's just too much variation for me to trust a random battery pulled from a depot of them.

The thought experiment that put me over the edge was imagine instead of batteries, we were talking about tires. What if it was deemed better to swap out your tire when you had to put air in it. So you brought it to your shop and they pulled the wheel and tire off, then put one that they had in-store on full of air, and they refilled the one you gave them and handed it to someone else.

Would you trust that? How would it change how we handle tires on cars? Would the public go for it? I really don't think they would, I know I wouldn't, and it's the same kind of feeling with car batteries.

I like your tire analogy. While it is probably true that the risks would be lower with battery swaps, it is also true that the marginal benefit isn't so great as people tend to perceive.

Would you take the marginal risk of a battery swap (plus the costs of all those batteries in inventory throughout the country) in order to save 60 minutes on a 600 mile trip?

And is the infrastructure to do all of that really less expensive than putting a charger at enough restaurants for you to just stop and eat while the car charges?

>Would you take the marginal risk of a battery swap (plus the costs of all those batteries in inventory throughout the country) in order to save 60 minutes on a 600 mile trip?

I honestly think I would for a trip like that. But at the same time I wouldn't want to be stuck with a potentially "sub-par" battery after that trip either. And those 2 things seem pretty at odds with one another.

Like in a perfect world I'd love to be able to have it as an option, but I'm not willing to give up "my" battery in my current (hypothetical!) car for one of unknown quality.

Perhaps a "booster" system would work then in this case? You don't swap out the actual battery in the car, but instead swap out batteries that go in your trunk or something and charge your actual battery while driving! Then you don't care about how shitty that pack is, you are only using it to "recharge" on the go!

600 miles is equal to about 10 hours of driving (very roughly). There are very few people who would do that trip without stopping at least a few times (bathroom, food, stretch, etc...) and if charging infrastructure is common enough (which it will be) than a good chunk of those 60 minutes can be done in concert with those stops. And compared to ICE vehicles, most would need about 2 re-fueling stops to make that trip[1]. So an aggressive ICE trip would still result in about 10-20 minutes of re-fueling time.

Another thing to consider, it is much more likely that we will see 400mi range electrics sooner and/or easier than we could roll out a large network of battery swap stations. I think the concept of battery swap is solid. Most batteries have BMS systems that prevent over/under charging and any physical damage can be detected. Plus the battery would likely be owned by a third party, so it would not be a big deal if you got stuck with a bad battery, you would just swap it out for another one. The main issue is logistics. Much harder to build a network of battery swap stations then it is to put some fast chargers in parking lots. And if we can get the range up to 400 miles, then a 600 mile trip could be done with 20-30 minutes of super charging.

[1] Assuming a ~300 mile ICE range, you need to fill up at the start, at the middle, and at the end (although one could wait till the next morning, but I think it should still count). Whereas electric, you start full (because you plugged in overnight prior to departure), and you end full (assuming you can plug in overnight at your destination). These are rough assumptions, but I think 2 fuel stops is a good approximation, but many would need 3 (including my own ICE car, which gets ~250 miles per tank).

> if charging infrastructure is common enough (which it will be) than a good chunk of those 60 minutes can be done in concert with those stops.

This was really the point that I was getting at. It is ultimately cheaper to put good chargers at every restaurant and bathroom stop than it is to put battery swap stations (with inventory) at enough locations.

If you or someone else can do it, I genuinely encourage you to! I do think that ideally battery swap tech could be a big benefit, but I just don't see it taking off for so many reasons.

The major one being your first paragraph. Charging tech is getting better every day, and we are already at the point where 15 minutes can get you a good chunk of charge with current batteries in some cars. I think things will change (no more "gas stations" (or places solely devoted to providing fuel), and a lot more charging spots at destinations that are worth spending 30 minutes at), the bit of charging time every few hours will begin to become a non-issue, and the whole complicated logistics nightmare of managing a fleet of physical battery packs at various depots across the country will go the way of the flying car. That thing that everyone thinks they wanted but it was just never practical to have.

You assume gasoline is fungible, right?

Gasoline is largely fungible because it's required by law to be. What can be called gasoline, what additives can (and are required to be) put into it, how much energy it has per liter, etc., are all regulated.

There was a time where gasoline brands mattered, and the gas you got from Esso might have been slightly different than the gas from Sinclair or Hess or whatever, but that was intentionally regulated into irrelevance because the benefit to consumers of a consistent product was more valuable than allowing brands to differentiate themselves.

It took several decades after the widespread adoption of the car (and gasoline as the dominant fuel) for this to happen, and during this time users had to struggle with varying fuels produced from different feedstocks, gumming of engines, dilution of crankcase oil, etc. (This is referred to in period motoring publications as "the Fuel Problem".) The automobile industries and the oil industries basically pointed fingers at each other until the US Bureau of Standards had to step in and mediate on a consistent set of standards that the refiners would produce fuel to, and the engine manufacturers would design their engines against. If this hadn't happened, and the market had been left to sort it out, I suspect you would have ended up having to fill your Ford car only at Sinclair stations, based on some Ford/Sinclair arrangement or whatever.

Unfortunately the 'solution' to the Fuel Problem in the 30s involved the introduction of tetraethyl lead, which mars what would have been a good example of mutually beneficial public-private cooperation and useful regulation.

to an extent that it matters, yeah.

Sure, I put 87 octane in our SUV and 89 in the audi, but yeah for the most part gas is gas, unless something is wrong.

Getting 2 random batteries to have less than 10% variance among them is going to be a lot harder (especially when battery health changes a lot depending on how they are treated. Users running them to near empty in cold weather is going to shorten the life a lot faster than the guy who only runs it to 50% before swapping out every time), and I have a feeling that the amount of "problem" batteries will be much higher than the amount of times i've ever had "problem gas" (which is basically 0 times so far).

Side note: is that a typo or do you really have 87 octane gasoline in the USA? Because it's 95 and 98 in the EU.

yes, but we use a different method of measuring than you do.

IIRC ours is the average of 2 different methods (it normally shows as R+M/2 on our pumps), whereas I believe the EU uses only the one that tends to be a lot higher (RON I think)

Most gas stations around me have 87, 89, and 91, and sometimes 93. I believe your octane numbers will be on average like 6 higher than ours for the same gas.

They're possibly different measures, RON vs MON. The wiki article has more including a photo of an offending US gasoline pump https://en.wikipedia.org/wiki/Octane_rating

I am assuming in a hypothetical battery swap world batteries would be rigorously tested before replacement. How hard do you think it would be (sincerely)? For the gasoline analogy, there are lots of ways to achieve an octane rating but I suspect most people only use the "do I hear engine knock" test. Similarly, I would be fine of a guarantee of if I have 300 mi of electric range (whether it's 300, 310, or 320) under normal driving conditions for a battery swap, as a trade off for convenience.

I really think it would be a lot harder than testing gasoline.

For starters, with gas and other things like it, there is a supply chain which is pretty tight. If one supplier starts giving bad gas, you can blacklist them and move on. With batteries you'd have to test them after every single use, because you don't know what the last user has done to them.

Then they need to be physically inspected, because a puncture or deep gouge or crack or something could cause big issues.

Then their actual capacity needs to be tested some how. I'll admit that I've been outside of the battery ecosystem for a while, but years ago it wasn't all that easy to "spot check" a random battery to find it's health and capacity. Most devices would gain that knowledge about a battery over a few charge cycles. You need to make sure you know it off the bat, and you can't be wrong or I'll lose faith in the company and the tech.

Then throw in the complication of different sizes, different shapes, different technologies, different requirements (this isn't just the "gas" part of fuel, it's also the "gas tank", so one size will never fit all), and now you are maintaining huge banks of different kinds of batteries all while charging them to the right amount without degrading them, and checking that users didn't run them in below freezing to almost 0 percent which would reduce the lifetime and aren't damaging them in any way which would be very unsafe.

In an ideal world, it sounds like a great idea, but I just don't trust that it can be pulled off without making the user's life worse than if they didn't do it.

A couple of things: when I think about it, I implicitly think about it as a vendor specific thing. Like Tesla supercharger stations. Agree that battery standards across makers likely impossible. Second, I think the major upside is removing a large potential liability from each vehicle - as hybrid vehicles are entering "old used car" ages/mileages, all your points about assessing the health of the battery apply to 2ary buyers and ability for people to monetize their old vehicles.

Bringing it back around to the topic, I don't know that we can wait on solid state and this represents a work around while smarter people that I can figure that out.

If you investigate the way gasoline is distributed in the US you will see that it is extremely fungible.

Sure, but my point is that you have gasoline being produced by many companies and production facilities, from many different/blended inputs (heavy oil with low gravity, NGLs, ethanol mixture, et al), and with proprietary additions.

There's no reason that batteries can't be checked that the meet spec before they are replaced in your car in the same way.

I'd be surprised if each battery couldn't come with a little computer that tracks charge times, cycles and power output over time. It would make it trivial to monitor whether or not a battery is currently serviceable (or whether it will expire prematurely).

For EV fleets we used to only be able to do this per vehicle (not by battery) while the vehicle was home and charging, by shipping the fleet battery metrics to a central aggregator. But that is overkill for consumer vehicles.

With Tesla, every single cell has a computer chip monitoring its performance on a variety of issues. And the aggregate data for that is all called back to HQ on a regular basis. Tesla knows better than you ever possibly could as to how well each and every cell in your battery packs is doing.

Yea, worth noting that the small-tank propane market also works like this. When you go to a supermakert or gas station, you just swap an empty tank for a full one. Refill is done after hours at scale.

Notably, 10 years ago I could swap a butane or propane tank from one vendor with one of another vendor at any place that sold butane/propane.

The last time I tried to do that (6 months ago) they rejected it. I had to go to the original supplier, as they were no longer refilling each others branded containers. In spite of standard fittings/sizes/etc. They've become significantly less fungible, and I can no longer just go to the nearest or cheapest supplier based on my needs.

Even worse, I've just realised that I now effectively have two un-refillable tanks, as Homebase just shut down all my local branches. Which I paid deposits on when I bought them, obviously. Nice ...

uhaul will generally fill propane tanks. When you swap tanks you get substantially less than what uhaul will fill to.

Yep. They also over-charge for propane, sell the tanks not fully-filled, and don't compensate you for propane left in the tanks when you return them. All to increase convenience slightly (I can get the swap tanks at the supermarket or Home Depot, but I have to go to a specific gas station to fill the tanks I own). I strongly prefer the non-swap solution.

It works almost the same for bottled oxy/fuel/shielding gas used for cutting and welding operations across the country.

Oh, that guy. I met the Better Place CEO once. Good looking, great talker, knew many national leaders, totally unworkable business plan. Along the lines of "take over the world, with 10x growth per year." In a business where you actually have to build stations and cars, not just distribute software, and the margins are low. I wouldn't go all the way to "con man", but it was close. More like someone who bought into their own hype.

Automated battery swapping takes tight standardization. It's in use for some industrial robotic AGVs.[1][2][3] Mechanically, it works, but all the vehicles have to be very similar. A taxi fleet, maybe.

[1] https://www.youtube.com/watch?v=lvqbw0UT5pM [2] https://www.youtube.com/watch?v=uKg8Zxmmpv4 [3] https://www.youtube.com/watch?v=vJwtwdeAXhM