Okay, look, just hear me out: I’ve been going down a bit of a rabbit hole about Renault Estafette vans – did you know they were Renault’s first FWD vehicle, coming out in 1959, before the Renault 4? It’s true! Anyway, they’re fascinating machines and probably deserve a full story sometime on here, but for now, I just want to focus on one detail, and how it got me thinking. That detail is how the whole drivetrain just rolls out of the front of the van, on its own two wheels. What if we applied this idea to EV battery swapping?
Now, I know that a roll-out drivetrain wasn’t invented by Renault – in fact, I wrote about another van that did this with a rear-mounted drivetrain, the White Horse, and that one came out in 1939! But, it was when I saw that picture up there that I started to think about it.
So, as you can see, the whole longitudinal FWD drivetrain is an integrated unit up front there, and it just rolls out the front of the Estafette. So, let’s just play with this idea, what if that drivetrain was a big battery pack and an electric motor drive unit? And when the battery was drained you could just pull into a swap station, maybe the car drops some spring-loaded arms to support itself, and the drive unit, using a small amount of remaining electricity, creeps out of the car on its own power (stabilized by maybe a little drop-down caster), and then you can guide it to some recharging stall (that also checks things like the motor condition and tire wear) and a fresh, charged one then creeps out, ready to be guided to your car, where it backs itself into position and locks in, automatically?
You could have one of these units at the front and rear, and you can choose the type of units: full batteries and full motors, just battery, just motor, or just wheels and suspension. You could transform your car from AWD to FWD or RWD three times a week, if you wanted. Or, you could put motor/battery-less ones in both ends and be stranded, if that’s your kink.
This double-end approach may lend itself to some kind of underfloor cargo area, like a tour bus, where most EVs carry their batteries today.
You’d pay some sort of monthly fee for this privilege, but you’d also pay a lot less for your car, because you’re buying something without all of the complicated battery or motor or suspension parts. Hell, technically you wouldn’t even own wheels.
In return you’d get battery swapping and zero maintenance worries, because all of the major mechanical parts are swapped out, maintained by whatever companies – and I’m imagining these types of cars as an open standard, so any number of companies may make compatible drive/battery/wheel units that fit. A cheap entry into EVs, plus a monthly fee, plus battery swapping (I bet you could plug these in, too, if wanted) and zero maintenance or repair worries.
Sure, there would be some drawbacks, like not getting to pick your wheels or maybe not getting access to exactly the motors or batteries you want, but because it’s so easy to swap, it’s not that big a deal.
Maybe most days you just have the low-end FWD battery and motor pack, but then you decide to drive to Tail of the Dragon, so you splurge and get the most powerful RWD package you can get and – oh! – a motor and battery-less front end, but it has a weatherproof frunk built in instead! And then if the weather gets bad on the way home, you can stop and get motors/batteries at both ends for an AWD setup, though you’ll have to figure out where to stash all the stuff you had in that frunk.
The beauty of EVs is that this sort of thing is actually possible, and I suspect many, many possible EV owners would love something with mechanicals that they just don’t have to think about at all. Plus, as new battery and motor tech develops, that could be deployed into the pool of swappable drive units.
Who wants to fund a startup? You can pick any title you want, even King/Queen Emperor/Empress or whatever. It’ll be fun!
Love how the example of the electric car is drawn as a Renault 4 😀
For why it probably will never work, look at the history of Better Place, the Israeli company which for a brief while was the global leader in drive-in battery swap tech…
Basically the auto makers could not be bothered.
Volkswagen air-cooleds basically had this concept as well. The entire engine + transmission can come out as a unit and be swapped. There was a company that did this, RVEECO, Rebuilt Volkswagen Engine Exchange Company. The intent was to be able to quickly swap out an engine (and maybe transmission too, I can’t recall) for another one. With experience, this swap could probably take place within a couple of hours.
I thought I remembered this, from the Car & Driver article “Worth the Watt: A Brief History of the Electric Car, 1830 to Present” August 2022
“The Electric Vehicle Company (EVC) had more than 600 electric cabs operating in New York with smaller fleets in Boston, Baltimore, and other eastern cities. In New York, the downtime it took to recharge batteries was addressed by converting an ice arena into a battery-swapping station where a cab could drive in, have its spent batteries replaced with a recharged set, and move on out. Brilliant, but like many a startup, it expanded too quickly and ran into unforeseen conflicts among investors and partners, and the whole taxi venture had collapsed by 1907.”
Forget this idea the only subscription i am paying for is for my Autopian subscription.
Swappable batteries would be a great thing.
Batteries would then be seen as the gas/petrol/diesel ( so an operational expenditure in corporate terms ) and not a part of the car ( a capital expenditure in corporate terms ).
If you manage to get all the car maker to standardize battery size ( small, medium large and even XL ), location and wiring, you can get semi-automated refilling stations that will replace you battery in a matter of minutes ( like refilling a gas tank ) for a fee ( the fee to recharge the battery you’re leaving behind. )… It would even keep motorway station and stops relevant as they would move into the battery swapping/refilling business. ( they would have to have enough power to refill many batteries and have enough batteries to meet the needs, but there’s market experts on that kind of thing that can probably give hard numbers for each battery size at a given location )
Now on the Estafette side. While I didn’t know about the roll out drivetrain, though it explains why our alpinism club mechanic was able to replace the right front wheel ball bearing in less than a week on his own and in his garage. ( the cage around the balls broke, and I drove it from Gavarnie to Clermont Ferrand with crunshing/gratting noise every time I turned the wheel… Interesting time )
The idea is interesting, but I think it would be best suited in fleet or military applications, where the same entity owns and is fully responsible for all the hulls and power packs. There, I think the primary advantage of rapid redeployment of discharged, worn or damaged units might be worth the extra engineering.
I’d be happy if we just had torpedo batteries, like giant AAA cells that get shoved in through a port on one side, and perhaps even ejected from opposite side. Or inserted and removed from the rear.
It can’t be that hard, and cylindrical cells wouldn’t require any special alignment when putting them in.
I like this idea, but for artificial spouses.
How is this better than coming up with a swappable battery pack available in a couple of standard sizes?
It’s an interesting thought… but seems far more complicated than it would need to be to be practical.
Seems the ideal solution would be a battery chemistry that allowed extremely fast charging. That way manufacturers would be constrained by “standard” battery sizes.
Remember for each battery size/option you need inventory. How many of each size so you have enough to service customers while the dead returns charge. Also would you get credit for charge remaining on the trade ins?
Sounds great, but I suspect in practice you’d end up paying so much for the swap service that it wouldn’t be worth it. Exhibit A: Every car subscription service.
People like the idea of flexibility, but they don’t actually want to pay for it.
I thought I remembered my dad telling me that’s how the engine and front subframe was set up in his Hillman Imp, but I just had a quick look and I misunderstood. He’d remove the front clip, jack up the engine, disconnect everything, then roll the car back on all four wheels, leaving the engine in place.
Edit, it was rear engined, so reverse everything I said.
(My kingdom for an edit button!)
I wonder where the exhaust is routed? Or is it disconnected before you roll out the drive train?
Appears to be hanging down in the middle.
Get your minds out of the gutter!
It’s no good. You’re not just swapping the motor and batteries, you’re swapping major safety equipment like tires, brakes, and suspension. Unless someone is on site to thoroughly inspect every unit before it gets swapped in, there’s a very real risk of being given a unit with bald/flat tires, worn-out brakes, bad wheel bearings, etc.
I say go for it. it should have been like the universal charging cord for phones and cars designed around the pack swaps.
This concept is far from new though.
The major issues most will spout abut is the cost of the battery being the majority of the value, so who is ultimately responsible for it in a crash or if stolen (these would likely be the next cat converter to crackheads). there is also the question of home charging and how to properly handle that. then there is the liability should the battery catch fire? Car MFR, Battery MFR or Fuel Station?
I think easier and better would be to have all car companies make a standard range extender slot, kind of similar to a cordles power tool. you could put it on the bottom of the car so you can back into it and connect it or something, or just have a rolling cart. but the car should have enough programming to either pull that power to it’s battery or reserve the plug in battery for when the main battery is below a certain threshold and then flip to the aux battery. I think 50 miles for pack like that without water cooling or whatever would be ideal.
Cool idea, Jason, but I think it’s much too complicated and fraught with potential problems. I’d much rather just recharge the battery like I do now – it’s not that big a deal. But If we’re going towards a post ownership society, then I’d much rather just swap the entire vehicle. Drive in with my dead battery car, grab all my shit and pick out a different fully charged car, and drive away. Or, drop off the 2 wheel drive car in October and pick up an AWD car or truck to use for the winter. All included for the price of one monthly subscription.
Near that time period(1960), Renault Dauphines were used by National Union Electric company to make a conversion called the Henny Kilowatt. It was not designed with battery swapping in mind, unfortunately.
There were two versions. The first was a 36V system that topped out at 40 mph and got a 40 mile range. The next iteration used a 72V system, and could top out at 60 mph, getting a 60 mile range. A 7 horsepower GE series-wound DC motor was used, with a contactor controller running it(not a true controller, but a series of contactors, relays, and diodes that switch the battery configuration around depending upon position of accelerator pedal to adjust speed). They had a weight between 2000 lbs and 2135 lbs depending upon variant.
All the pieces of technology were there. With help from Renault, there could have been an electric Renault with a swappable battery back then.
But where would be put the frunk?
Was the drivers seat in those vans really that thin?
I would assume that people would ‘subscribe’ to a car service instead of owning the car… otherwise, imagine tracking of warranty issues, the tire and brake wear and of course the liability. If you are subscribing to a car service, it would be much easier to pull into the charging station and just switch to a different, fully intact vehicle. Drop of a truck, drive away in a sedan. Why piss around with all the complexity of switching components?
Adding on nlpnt’s comment. I think subscribing to a battery service would be more practical. The station would probably just use a forklift to insert and remove batteries from the side of the vehicle. The concept would be similar to switching batteries in a rechargeable tool, just on a bigger scale.
I loved Renault Estafette when she was in the Miami Sound Machine!
Is that what DoYouHaveAMomentToTalkAboutRenaults is on about?
FeelTheIdleOfTheRenaultGettingStronger
HeyThere’sAnElectricHonda
Beat!
Did you forget about VWs effort in the 50s for EV battery swapout? This was both elegant and simple, Although heavy. Think VW single Cab and Double Cab “treasure chest” area. Using standard electrical connectors of the time. 1. Disconnect Battery pallet. 2. Remove small pallet of Lead Acid Batteries 3.Insert new pallet of charged batteries. 4. Reconnect Battery pallet. Drive away.
Sure they were heavy and limited range. But, it worked dead simple. Perfect for warehouse areas or places where sparks of ICE were dangerous.
I suggested a modular design for EVs in a discussion here the other day – using two high-performance motors for track days, reconfiguring to one motor for long-range road trips, etc. – so I tend to agree with your approach.
People are (rightly) not happy with manufacturers charging subscriptions to activate features like heated seats, but for the modular motor/battery approach you describe it makes sense.
I remember seeing that the (I think) Chinese were doing swappable batteries at pay-stations for their box trucks and such. It was in one of the deep dives that was on here a while back.
I like the idea of a fully swappable drivetrain, but I fear you’d get into some severe logistical issues.
Knowing my luck, I’d get a mostly bald set of tires right before a snowstorm.
You’re onto something, Jason, but why can’t the swappable/modular batteries be under the car and *not* include motors, wheels and tires? There’d be some kind of hoist at the swap station – standardization would be a good idea here – and latches rather than bolts would hold the batteries in their underslung position, with the latch releases inside the car and designed in such a way they can’t really be thrown without the battery being supported. Maybe some sort of interlock with the key transmitter?
Release would be a two-person job, one of whom has to have access to the car interior; at an official swap station only one tech would be needed with the car owner releasing the latches from inside, but theft would be made as clumsy, time-consuming and conspicuous as possible to deter it.
Check out this article from July that details all of the battery swapping attempts in China: https://www.theautopian.com/china-is-already-doing-ev-battery-swapping-and-heres-everything-you-need-to-know-about-it/
I’ll make you a deal, you find me a way to roll those Renault assemblies under a Tesla instead and then we’ll talk.