Model S Motor And Volt Battery Go Together Like Peanut Butter And Jelly

A common project category on this site is “put a Raspberry Pi in it”. For people who wrench on their cars, a similarly popular project is the “LS Swap”. Over the past few years, the world of electronics and automotive hacking started to converge in the form of electric car conversions, and [Jalopnik] proclaims the electric counterpart to “LS Swap” is to put a Telsa Model S motor and a Chevy Volt battery into a project car.

The General Motors LS engine lineup is popular with petro heads for basically the same reasons Raspberry Pi are popular with the digital minded. They are both compact, very powerful for the money, have a large body of existing projects to learn from, and an equally large ecosystem of accessories to help turn ideas into reality. So if someone desired more power than is practical from a car’s original engine, the obvious next step is to swap it out for an LS.

Things may not be quite as obvious in the electric world, but that’s changing. Tesla Model S and Chevrolet Volt have been produced in volume long enough for components to show up at salvage yards. And while not up to the levels of LS swaps or Pi mods, there’s a decent sized body of knowledge for powerful garage-built electric cars thanks to pioneers like [Jim Belosic] and a budding industry catering to those who want to build their own. While the decision to use Tesla’s powerful motor is fairly obvious, the choice of Volt battery may be surprising. It’s a matter of using the right tool for the job: most of these projects are not concerned about long range offered by Tesla’s battery. A Volt battery pack costs less while still delivering enough peak power, and as it was originally developed to fit into an existing chassis, its smaller size also benefits garage tinkerers fitting it into project cars.

While Pi SBCs and LS engines are likely to dominate their respective fields for the foreseeable future, the quickly growing and evolving world of electric vehicles means this winning combo of today are likely to be replaced by some other combination in the future. But even though the parts may change, the spirit of hacking will not.

[Photo: by Jim Belosic of motor used in his Teslonda project]

55 thoughts on “Model S Motor And Volt Battery Go Together Like Peanut Butter And Jelly

    1. Well, the first Model S cars hit the market in Q3 2012 so they’re just about 7 years old now. In 2-4 years you should start to see a steady trickle of Tesla cars with functioning power electronics but dead batteries – once they hit their shelf-life.

      Some owners may have paid the $12k in advance for a replacement battery, but others are likely to swap for a cheaper EV. Word on the wire is that Tesla is charging $24k for a replacement Model S battery, so you have a choice of paying 2/3rds of the way to a Model 3 to keep your old car, or just buy the new car and sell the old one for the difference.

          1. On another point: so is my phone, but I will stop receiving software updates/upgrades well before the battery would be due replacement in about 2028, so the point is moot.

            Same thing applies to the Model S. It’s been made since 2012 and it needs a software upgrade to install a new battery the official way. The original production schedule was supposed to end around 2020, and they’re only legally required to provide support until the end of the warranty of the last car sold, so it’s likely that you won’t be able to buy a new battery anymore after 2028 because you can’t get Tesla to update the software to accept it. You have to hack it. This depends on whether Tesla will continue, and for how long, to sell the Model S and whether they’ll start dropping support for the earlier cars due to differences in hardware between the early and late versions of the same car.

          2. Coincidentally, Tesla has removed the clause where they offer lifetime software upgrades to the cars from their website, and are refusing to disclose for how long they will offer the updates, so it’s not clear whether it actually is covered under any sort of warranty or law in the first place.

            So it’s a bit of a loose noose anyhow. As long as they’re not saying this or that, they can pull it off at any time without legal repercussions.

          3. Go read the Tesla forums. If Elon drops support for the Model S, the loyal users will go “Thank you sir, it was our fault anyways”.

            I just read a long thread about a guy who asked what Tesla actually meant by “lifetime software updates”, i.e. can he rely on it in any sense – and everyone else in the forum just went “Hisss! You don’t ask that question!”

      1. The problem with that is that the batteries aren’t dying in droves. They seem to be holding up pretty well in the long run. It’s other stuff (like that ridiculous heavy logging/failing memory issue) or accidents that are killing them off.

        1. Consumer electronics get replaced well before you hit the shelf-life of lithium batteries, so you never see the problem. On the rare chance that you have used a cellphone or a laptop well past its warranty, and you’ve otherwise treated your battery right, you’ll have noticed that lithium-ion batteries start to peter out after 8-9 years and completely die after about 10 years.

          Same thing applies to EVs. Long term testing so far as they have actually been done show a maximum lifespan of about 13 years under temperature controlled conditions with low charge/discharge rate (1/12 C) – but that’s for earlier generation batteries with lower energy density (lower self-reactivity). The quest for higher and higher energy densities makes any battery more unstable and maintaining a decade of shelf-life is a challenge.

          1. You’ve convinced me not to get a Tesla. I want reliability (no leaks with ev). But if my battery won’t last as long as my Camry, then I’ll buy Camry.

          2. This is at best uninformed. Reality is Tesla pack degradation is very low, actually slowing beyond the first couple of years. Eventual long term pack life is of course an unknown, but it can be extrapolated from accumulated data. Data says packs are lasting the lifetime of the vehicle with few exceptions. The new stuff is significantly more stable, not less. New packs this year have a design life of 1 million miles. The chemistry in use here is substantially different from older consumer electronics and anecdotes of cellphones petering out are not relevant to EV cells. Joel is absolutely correct in observing reality pack death just isn’t really a problem and were you to be an unfortunate outlier plenty of seconds hand packs from crash damaged vehicles are available.

          3. > Reality is Tesla pack degradation is very low, actually slowing beyond the first couple of years.

            Yes, that’s what lithium batteries do. When the battery gets old, it loses active materials to side reactions that inevitably happen over time and that makes the wear-out mechanism faster and faster. Cycles count more for an older battery than they do for a younger battery.

            The battery stabilizes for a while, and then it undergoes a rapid exponential destruction. This is observed with all lithium batteries regardless or chemistry or use. You can slow the process down by babying the battery with optimal temperatures and low charge/discharge rate, but it will happen anyways.

            It’s actually better this way than having a battery slowly fade away, because the range anxiety will kick in at some point and you’ll have to replace the battery anyways because it leaves you a mile short of your destination.

          4. >New packs this year have a design life of 1 million miles.

            Yeah. If you do it fast enough. A typical EV energy consumption is 250 Wh per mile. A million miles is therefore 250,000 kWh which for a 70 kWh battery is technically about 3,500 cycles. The new NMC chemistry developed by Tesla and others is capable of reaching this cycle life, but this says nothing about the calendar life.

            A regular driver will drive about 15,000 miles a year, so 150,000 miles in a decade. The battery will rot of old age before it gets through all the possible miles you -might- drive if all you were doing is driving the car day and night.

          5. > Eventual long term pack life is of course an unknown, but it can be extrapolated from accumulated data.

            That’s exactly wishful thinking that ignores the actual chemical processes that go on inside a lithium battery. It can’t be extrapolated from accumulated data because it is already known that lithium batteries don’t wear out linearly.

          6. Also note that when you are driving the car, the number of cycles you go through in a year is not constant but increasing due to the loss of capacity, because you have to charge it more often to drive the same distance. It doesn’t show up at first because the difference is just 1-2% but when the battery is worn down by age and use, and you’ve lost 20%, then it’s a different story because then each cycle operates on 20% less of a battery and you’re using 20% more cycles anyways for a combined 44% additional wear. In reality, the rate of decay accelerates faster than this because the poor condition of the electrodes causes further losses and side reactions that aren’t supposed to happen.

            As soon as you lose a little bit of capacity, it creates a self-amplifying spiral where the loss of capacity causes further loss of capacity, exponentially. This is why a battery is considered “dead” when it reaches 80% of its original design capacity – after that it’s going downhill, fast.

            And from the point of reliability, when you have a battery made out of 8,000 individual cells, even when the failure rate of an individual cell was 1 in 5 million, the probability that you’ll have an “incident” with at least one of the cells in the battery becomes 1-(1- 0.2*10-6)^8000 which is approximately 1:625. If just one tenth of those failures lead to fire, its still worse than the average rate at which cars burn down.

          7. I’ve never had a cell phone battery last more than about 2 years. My current phone is 3 years old and needs 2 or 3 charges a day. I’ll say EVs should have safer DOD on their batteries than my phone does though, so hopefully they’ll be more stable. Teslas seem to be holding up well so far, I remember reading an article on someone who has a fleet of them for a car service and they were doing very well with 400k+ miles on them.

      2. I think this is an issue that hasn’t been very well covered by the media – the whole price curve for used cars changes when one component is responsible for a very large part of the cost, and it is has a limited life span..

        This isn’t true for petrol cars, I have one car that is 25 years old and is still going fine (coming up to 300K kms..). Yes, it has probably dropped in value 15% per year (why I normally buy 3 year old cars) but it STILL works..

        Electric cars have a completely different curve, as the battery price is effectively a repair cost at a certain point. Nobody is going to pay a quarter of the original price at year 8 (which would be normal for a petrol car) if they have to pay 40% of the original car value to keep it working in 2 years time!

        So it’s going to be interesting to see what happens. I suspect – and I certainly have some ideas :-) – we will find other uses for the old motors – that should last way way longer than the batteries – that don’t include the very expensive batteries…

          1. Yes it can. Every year adds rust and little problems that cost the value of the car to fix, so they don’t get fixed, so the car keeps rotting until the most valuable parts are the wheels and the gasoline in the tank.

          2. After all, if your car is valued at $1500 and the alternator is due replacement in a year or two, the cost to get it replaced can easily be 15% of the car’s value, so anybody buying a used car would be looking forward and already betting that they need to pay about $225 in repairs to keep the car running the next year.

    1. Just to be slightly pedantic, the LS is a small block from GM that is used in many Chevrolet’s, but it is not the SBC. The “Small Block Chevy” was discontinued in 2003 after having all of its roles replaced by the LS.

      I say ‘slightly’ because it may seem like splitting hairs, but if you were trying to order parts or talk to a car guy and you called an LS a SBC, they would be very confused.

      1. Indeed it’s interesting that “Small Block Chevy” used to refer to a V8 Engine based on Chevy’s Small Block architecture, but with the LS engines having taken them over, SBC now refers to the architecture itself rather than the block make and size. This reminds me of what happens when somebody uses the name “new $oldthing” to differentiate it from that which it replaces, only to be replaced by another new thing some time later, at which point naming conventions fall apart and somebody ends up calling it “neo$oldthing” or some such silliness.

          1. Somewhere in there GM decided Ford had a Better Idea (TM) and finally gave up their silly old siamesed middle exhaust port. Their new head design was like they took a 351 Windsor head and modified it a bit to fit the 350 Chevy.

            Of course that made it even more likely that people would put Chebbby V8s in Ford hot rods because with the different exhaust port arrangement it’s more difficult to tell at a glance that a customized Ford has the wrong engine.

            If’n I had vast amounts of disposable income, I’d build a dozen different GM customs and hot rods, all with 100% Ford drivetrains, just because. I’d call it the Revenge Fleet. ;)

    1. It depends on the year model, but generally generation one and two are both 360V, but with different battery chemestry. Gen 1 uses a 16.5KW battery of which about 10.9KW are actually used, to preserve battery life, and a second Gen uses a 18.4KW battery of which only the middle 14KW is used.

        1. The software does not let the battery charge all the way to 100% or let the battery drain to 0% so the top and bottom appx 10% is unusable so you just use the middle 14KW

  1. I’ve hard this FUD about every commercial hybrid and EV so far and it’s never turned out true yet. Do you guys never give up?

    It’s like listening to cops talk about the “street value” of whatever contraband they just seized. The fantasy pricing is always hilarious.

      1. I suppose he’s referring to the battery price speculation.

        But it’s perfectly warranted. Tesla’s can now produce the plain cells at $150/kWh. Assume $120/kWh and multiply by 100 kWh = $12,000 per battery. Double the cost to get a profitable retail price and you’re at $24,000 replacement cost for a battery. There’s no incentive for Tesla to sell any lower because they want to sell new cars for more revenue, not maintaining a second hand market of Teslas that is directly competing with their own sales. Why would they?

        A 2013 Tesla can already be had for $30,000 and with 2-3 more years it’s going to be worth less than the cost of the replacement battery, so who’s gonna buy it? Nobody. People would rather spend the money on a new Model 3, which is the whole point.

        Look forward to very cheap Model S cars with dead batteries in a couple years.

        1. The speculation is warranted and Tesla buyers should go into the purchase with their eyes open.

          That being said, there are already 3rd party shops that swap out a degraded batteries. WK057 is the famous one. For $13,000 incl. installation he will take your degraded 60kwh battery and install a 90kwh replacement. Not so bad for a repair that includes a big range upgrade.

          The price is less than you expect because the degraded battery retains value. He salvages the good cells and sells them for off-the-grid home power etc.

          1. I’ve no access to Reddit at the moment, so I apologise if this question is already answered there. How does the software config. work after the replacement? As I understand it the software also needs to be aware of the larger battery capacity. Or does it stay a 60kwh model, but just with a potential to “upgrade” 90kwh? But, I just assumed that a 3rd party battery replacement voids the support warranty and, thus, Tesla probably wouldn’t upgrade the battery capacity in the software, would they?

          2. >the degraded battery retains value

            That’s dubious. Tesla’s batteries aren’t the safest type in the first place, and sorting out the good from the bad cells is pretty much voodoo business since there are no reliable universal indicators – not even cell resistance/impedance can really tell you what the state of the cell really is except when it’s really going bad.

            So you got a “new” pack made out of salvaged cells from batteries that other people swapped in, which explains the low price. You lose whatever warranty you had left, and you can’t take the car to Tesla for service anymore even if you paid money because you’ve tampered with it. They’ll tell you to “pound sand” as the other commentator said.

            So what happens to the OTA software updates then? You lose them as well?

  2. What is the profit margin on a new model S/3/X? Why would they need to double the replacement battery cost to make money and keep their cars on the road? The used market would warrant a decent trade value(15%?), directly to Tesla of course, after 8 years with a brand new “power plant” that they can turn with the same drivetrain warranty offered now. There’s still money to be made on the original release models.

    1. >” Why would they need to double the replacement battery cost to make money and keep their cars on the road?”

      Because a) nobody sells at cost, b) the cell cost isn’t the full cost of manufacturing the battery, c) taxes, d)labor to install the battery.

      If your cost to make something is $1 and you sell it for $2 then your gross profit margin is $1. Then you pay taxes for 25 cents, labor costs for another 25 cents, other costs like marketing, legal department, warehouses, transportation…. etc. and pretty soon you’ll have 5 cents for profit.

      It’s a general rule of thumb to double the cost to manufacture something to arrive at a reasonable retail price that still makes profit. Often times a more realistic approach would be 3-4x the cost, and with some products it’s 10x (clothes mainly).

        1. I understand and can appreciate the basic business model but we aren’t talking about someone that normally operates within that scope. His general business practices fly in the face of what most would consider profitable, and I’m not 100% sold on their sustainability. I don’t know the answers but I can guarantee these questions have been asked and a plan is in place for such events.

          1. No, we’re talking about exactly someone who is operating within the scope. The whole point is that Tesla is bound by the same economic realities that any other company out there – what they’re doing is making you hope and believe they aren’t.

            His “general business practices” are not special. He’s just leveraging the hype and other excuses to pump investor money into the business to be able to operate at a loss for year after year. This is not sustainable in the least, and Tesla is at a point where they have to start making profit now or fold. They can’t keep selling at a loss forever.

            Now that they have the “people’s car” Model 3, they’ve met their self-defined targets of the three step plan as laid out by Elon Musk (or at least pretend to), and they can’t argue any more losses on development. This is it – it’s boom or bust. No more excuses.

          2. After all, it would be pretty embarrasing if the original “three” step plan of going from a sports car (Roadster), to an intermediate luxury car (Model S), to an affordable people’s car (Model 3) had to be extended even further from the extensions and side-tracks they’ve already had (Model X) (Model Y)(Cybertrick)….

            The Model S was already supposed to be a $50k car that goes 300 miles on a charge, but it turned out to be a $100k car that doesn’t go 300 miles on a charge except with later upgrades to the model that cost extra. Tesla has consistently promised twice and delivered half, and while the fanboys have excused the behavior on account of cognitive dissonance (“If I criticize Tesla, it won’t become true”), real investors got wise some years ago.

            So now it’s showtime. Expect Tesla to pull off some tough love on the customers as they have to re-structure from a dot-com-bubble type of scam company into a real business.

          3. Or, in case you haven’t noticed, the last moves from Tesla to get funding were pretty desperate. For example, they released $1.6 billion worth of senior notes, which is a plain IOU that simply says you’ll be the first in line to be paid back if the company folds.

            Of course, assuming there’s enough money left in the company to pay you back. If not, your slip of paper is worthless. This is the corporate equivalent to going on the street corner asking random people passing by to spot you a twenty, so you can buy gas to go to work. Promise to pay you back tomorrow – honest!

  3. so thanks to the almost ubiquitous Leaf swap, I am finally able to consider an ev build. But I was concerned about the extra work (and potential bump-steer issue) of using a fwd system to run a rwd conversion. Using a tesla rear end (which is still prohibitively expensive and not nearly as easy as the volt parts to source) means I can avoid that little engineering hassle!

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