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Comment by akersten | Hacker News Reader

I think recharging is a transitory solution anyway. The real game changer will be automated battery swaps.

Imagine stopping at the charging station and having the entire battery pulled out and replaced with a charged one, pit-stop style. It completely neutralizes the #1 complaint about how long batteries take to charge, since there should always be a supply ready-to-go at the station.

This would be an automated, underground mechanism - you wouldn't even have to leave your car.

It will be faster than filling up a tank with gas.

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Nio has implemented battery swapping in China:

https://www.topgear.com/car-news/big-reads/power-shift-batte...

I don't see it catching on. It's too much logistical hassle. Battery packs can't be delivered as easily as fuel or electrons.

They’re not really delivered though, they’d be swapped and charged onsite ?

And then you'd have people who would try to rort the system by swapping a bad set of batteries with a good set from the station, and then sell it for a profit.

Why? If the modus operandi is to swap batteries instead of charging then you are effectively leasing the batteries and just buying the charge on them.

it's not convinient to fully disable charging at home, a lot of folks will revolt. and if you have people charging their cars at night, you always have a chance of swapping a worn out battery for a good one.

Of course. But if you know you don't really own the battery, and the swapping capability is in the price it is a non-issue. We already have something similar here, in Australia, for swapping LPG/propane gas bottles. You can refill if you want ( it is often cheaper) or swap with a full one. They are all dated so they also have "use by date"

And propane tanks are much cheaper than a large pack of litium batteries. Not worth it to steal a couple of dollars worth of metals from a propane tank, but the batteries are a large percentage of the cost of an electric car.

There would be measures in place to prevent this, of course. They'd have to be more robust than Redbox scanning for fake DVD returns, but you could sign the battery firmware, do challenge/response, etc. before allowing the swap to happen. All automatic of course. And if your battery turns out to be an elaborate fake - well, we know whose car it came from, considering they drove it to the station with a license plate attached.

> you could sign the battery firmware, do challenge/response, etc. before allowing the swap to happen

so either you're only allowed to swap batteries at these authorized stations (akin to today having a car that can only use petrol purchased from a particular brand of station), or it's trivially easy to swap it yourself (or with some easy to obtain equipment, like today's car oil change).

If it's the first case, then these cars are DRM'ed to hell and back. Not a good world for the consumer.

If it's the latter, then battery swapping will happen. It's https://en.wikipedia.org/wiki/Gresham%27s_law applied to batteries.

You could very easily have standards in place to ensure compatibility between garages ?

Yes, exactly. The batteries from customer cars will be recharged and re-used. You'd also have a reserve of extras for peak demand.

You could even automate health check-ups on the batteries this way too, and decommission the rotten ones from the fleet.

And stored and moved around. You have to have a stack of batteries ready to swap. You need someone to manage it whereas most chargers are unattended.

And when do you swap the battery? If you have 50% left but that's not far enough to get where you're going do you swap it out then or do you charge? And if you're charging anyway what's the value of the expense of the swapping system?

There’s always going to be some necessary repositioning in this kind of a logistic system. The LA Metro Bikes have the same kind of problem.

I think the problem is not going to be the technology, but the business model.

Electric vehicles as a financial proposition make much less sense when the cost becomes "and a $XXX dollar per month battery swap plan for as long as you plan on owning this vehicle". It also becomes problematic since batteries are the most depreciating major component on the vehicle. If you have a model where I can opt in to have my battery swapped for a brand new one without paying for the entire cost of the new battery, that business will not be solvent for very long.

Then there's the disposal/recycling costs. It's still not profitable to recycle the type of batteries we are putting in vehicles, so unless the government is implementing a new EV vehicle tax to help offset the recycling effort, any business model would have to account for that huge cost.

I think recharging is a transitory solution anyway. The real game changer will be automated battery swaps.

Battery swaps seem to have been a transitory solution. Battery forklifts and battery container shuttles at ports used to use battery swaps. But once batteries got good enough to run them all day, it was easier to just plug them in for a recharge when not in use.[1] Many electric cars can now go further without stopping than the driver can.

[1] https://www.liftway.ca/swap-your-forklift-batteries-for-the-...

Handling all those extra batteries would be complex and expensive. For one thing, batteries are not, and probably never will be, standardised between different makes and models of vehicle.

Most drivers, in most circumstances, would prefer to wait the extra 10 or 15 minutes to charge their own battery. After hours of driving, you probably want to stop for a snack or go pee anyway.

The technical problems might be easyish to solve, but I think the business/operational challenges will prove insurmountable:

- Need to standardize on a small set of form factors across manufacturers - Limitations to vehicle designs - How to prevent owners from swapping a battery with 1000 cycles of wear for one with 10 cycles (and vice-versa) - Getting the cost down to be comparable with plain charging (it would never be cheaper—the batteries need to be charged either way)

I think developments to fast charging will quickly negate any perceived benefit to battery swapping. Increases in capacity will also help, as will changes to expectations and habits for refueling (combining recharging with meals seems like an easy solution).

It will be interesting to see what wins out. I'm personally not optimistic that battery technology will get much better from a charging perspective than it already is. But that would be fine in my book too, if we reduced that to ~5 minutes. Anything longer feels like a regression compared to fossil fuels.

W/r/t standardization - yeah, mechanically there might be some interesting considerations like mounting points and common interfaces on the bottom of a car; but if the will is there, I'm sure there is a way.

Bad battery swapping isn't hard to discourage - if you poison the well, your vehicle is banned from the subscription battery program and you get to charge at home. Many ways a car can be tracked by the battery swapping station - especially if you have to sign in with your Tesla account/use an app to initiate the swap).

> Anything longer feels like a regression compared to fossil fuels

Not being able to fill up at home, or in the Target parking lot while I shop kinda sucks too - and those are much more common occurences than a 400 mile road trip. In reality, it's more of to a tradeoff than a regression...

The Cybertruck has a top end range listed of 500 miles. The solution in the end is going to be cars that last longer than the humans driving them (or the human passengers when we finally have autonomous cars), combined with ordinary charging stations in every parking location.

Battery swapping is complicated and capital intensive. It would have to solve an urgent need to catch on. But there isn't one.

Tesla tried this and interest was poor. It is also convoluted given you need to swap your battery out and put your battery back in.

problem is, batteries tend to degrade with time, and it's obviously not fair if you will change your worn out battery for an almost new one and only pay for a single charge.

I doubt it, we don't even have battery swap for smartphone.

It was already demoed by Elon and buried.

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