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Comment by jchw | Hacker News Reader

Question from somebody who does not know jack about automobiles: would electric vehicles last longer? Tesla was boasting its powertrain's longevity and it got me wondering if that was normally a limiting factor to a vehicle's lifespan and whether electric vehicles were better off. I mean, I'm guessing you've gotta replace the battery a fair few times, but are they as promising as they sound for longevity?

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It's hard to answer conclusively but early evidence is good. Their vague goal is a million miles on the drivetrain of the 3 but they warranty 100k miles, so the million is really an aspiration. There are people with 300k on their Ss already. No spark plugs, no oil to change. No fan belt, no transmission, no spark plugs or gas filter or muffler. Tires are the main thing people change. The early worries were about battery degredation. No degredation for me after almost 40k miles.

For the long term Tesla S owners, it looks like the battery degradation levels off asymptotically at around 90% and looks like the curve will stay mostly flat.

https://cleantechnica.com/2017/05/19/show-me-the-data-the-tr...

Is that battery running close to spec or does it have reserve capacity that it does not normally tap in to?

I wish I could answer. That's a better question for someone from Tesla.

Most Tesla owners charge the car only to 80%. The UI in the car for setting the limit encourages this by marking the zone from 60-80% as "Daily Usage" and the 80%-100% zone as "Trip".

When you purchase the car the default is also set to 80% and the delivery person tells you that you should usually have it set to 80% unless you are going to go on a long trip.

It's hard on lithium batteries to charge them up all the way and so Tesla and maybe some of the other car companies spreads the charge over more batteries to make their lives longer.

This seems amazing. Maintenance costs can easily overwhelm the average car-owner... if this is true, electric cars are more revolutionary than I thought they would be.

One major cost with Tesla is the insurance. I was quoted $380 a month on a model 3. I pay ~$700 for 6 months on 3 cars, 2 of them are 20 year old beaters and one is a new mini convertible.

Why is the insurance so high? I thought the safety features made it more safe == less insurance?

Anecdotally, my Tesla 3 costs the same to insure as my 2006 G35.

Just looked it up it’s $899 for the G35 and $913 per year for the Tesla.

It helps to not have had an accident or a ticket in over 10 years.

Same here - my insurance stayed exactly the same going from a 2010 Nissan Altima to a new Tesla Model 3.

Cost to repair and near absolute unavailability of non-OEM spare parts doesn't help.

It also seems like even moderate damage, which would NOT be a write off on an ICE vehicle, results in them totaling it because Tesla refuses to work on anything with even relatively insignificant damage (and they won't touch anything that has a salvage title, so never buy a used Tesla with a salvage title. Ever.).

A small part of it is the aluminum body panels, I think. Aluminum body panels can be repaired, similar to steel, but requires additional training/different tools. The Model S and X are majority Aluminum, whereas the Model 3 is mostly steel with a rear aluminum subframe. Basically if you get in a fender bender you need to go to a specialty aluminum body shop, which don't exist in high quantities outside of south bay.

Well, lower maintenance is the easy part, that's fairly obvious. The harder thing is making batteries at high rates and keeping them healthy and charging long term. One of Tesla's strengths is their battery heating and cooling system.

Honestly from my perspective as an ex-gearhead, older cars die from engine failure but newer cars just tend to wear out (assuming maintenance). The whole suspension starts to go (shocks, springs, ball joints, rubber bushings everywhere) and body welds, door joints, etc start to crack and sag. All of this is fixable, but at too high a cost. Thus electric cars won't really help this, to my eyes.

Although, it's very possibly a legacy of planned obsolescence (the good cost-saving kind) where the engine would last 200k so the rest of the car was only made to last 200k as well. Perhaps as engines start to last far longer, the rest of the car will be built to match.

> Although, it's very possibly a legacy of planned obsolescence (the good cost-saving kind) where the engine would last 200k so the rest of the car was only made to last 200k as well.

I think this is the answer. If a critical component of the car only lasts X miles, then building any other piece to last more than X miles is pure waste. As counterintuitive (and annoying) as it might seem, having all the parts of the car fail around the same time actually indicates that it was engineered perfectly.

A very fun poem on the theme by Oliver Wendell Holmes (the father of the famed American jurist): http://holyjoe.org/poetry/holmes1.htm

Because second hand parts are worthless?

Yeah, this. Right around 2-300k you need to replace almost everything rubber in the suspension all at one.

Is this because of the rubber drying out?

My understanding is that this is why tires need to be replaced after 5-6 years and are not safetiable thereafter. The dried out rubber is much harder than when it was first made and no longer grips the road as strongly.

If you drive 10-15,000 miles a year (about average), your tires will probably be bald anyway in 5-6 years

Yes, largely, the rubber hardens or has otherwise become worn

Tires actually dry rot from ozone exposure, theoretically, if you store a tire in an airtight container - it won't have a problem.

Even brake pads will last longer due to regen braking. A mechanic told me just today he's seeing Priuses in his shop at 80-100k with original pads.

Or Toyota just makes high quality pads. The pads on our Sienna lasted 92k miles over 6 years.

Somewhere in the 2000's, cars became too computer-controlled. In the old days you had levers and dials and that sort of things, or even resistor boards and sensors. Too many HVAC systems can only be controlled by the touch screen these days, as well as all the other options of the car.

At least in the past, you could replace broken parts or rig them on/off, but now everything is controlled by a stereo or touch screen which is $2,500 from the dealer and good luck finding a replacement in 10-20 years.

Ya, I think early-mid 2000s are the sweet spot for cars:

The OBD port will tell you everything that went wrong, no SatNav and knobs/buttons everywhere.

I dunno, people have been saying this about electronics in cars for longer than I've been alive, and I'm not that young.

I mean, first? finding a weird part is finding a weird part... and you are totally right that the electronics are the new weird parts and that way too much of the system is in the head unit, but... there have always been weird parts... and if you don't have a machinist (or these days an EE) friend helping you out, if you have a car with a weird part, you spend time in junkyards. (or the modern equivalents. Ebay has made finding weird parts so much easier)

My impression is that this is all as it has always been, except that it is easier to find weird parts than it was, and that if you want to make/rig a part, these days, you call up your EE friend rather than your machinist friend (and I have far more EE friends than machinist friends)

Me personally, I'm more comfy swapping out broken electronics modules than I am swapping out bolted-on metal parts, but either way, it seems like a pretty similar sort of thing.

I fail to see how an EE would be able to fix the problem with a trashed ecu. Once it's gone, it's gone, and there is no way of replacing it with a similar element without the producer know-how. The SW in those things is huge and you have great interconnectedness between the different systems.

I also couldn't machine a part for your carburetor.

My understanding is that the ECU controls the fuel injector, though, and that most of the inputs and outputs are fairly well known; and I'm told that it's a pretty simple control loop with the oxygen sensor, the TPS and mass airflow sensor. All in all, if it came down to it, I think I'd have better luck building an ECU from scratch than building a carburetor from scratch, after having fixed carburetors and fuel injected systems. Machining to those tolerances is hard.

(To be clear, I wouldn't put money on me personally doing either one of those things. I fix computers for EEs, and I'm no machinist. I'm just saying, micro-controllers aren't that hard if you are trying to do a simple thing... machining to carburetor tolerances really is.)

My understanding is that most cars don't have any sort of encryption between the ECU and the sensors; it's all stuff that someone with basic ee training could figure out with 20 year old equipment. If you have a popular/fancy car, people will sell you aftermarket/performance ECUs that are not recommended for use by the manufacturer, so while it's possible that it's a lot harder to do than I think it is, there's existence proof for the possibility.

I work in automotive embedded. And yes, the field is bloated. Yes, things could be more efficient. But even if all those problems went away, I still don't think it's feasible building one-off ECU's for usage in a friend's car.

Those things take a great amount of effort and time. The complexity is pretty big. Granted, I mostly work on instrument clusters, and I believe they are one of the biggest systems in the car, but the complexity is huge. I found it hard to carry the mental model of the whole system in my head.

After-market ECU's are deff possible, because you do a couple thousands of units at a time. But doing it for one ECU, I think not. Not if you put an upper-cap on the effort you are willing to expend. You're probably better off just buying a new car at that point.

Electric cars are going to have way fewer engine/transmission/brake issues. The nature of regenerative breaking means that you don't use the actual friction pads/rotors much. The nature of the electric motor means there's usually no transmission, and way fewer moving parts (and way less heat/explosive energy) than an ICE engine.

Battery issues are going to be way more expensive on an electric or hybrid car than an ICE car, which I think would be the primary downside.

Not really. The lifetime of the drivetrain will be about equal all told - 600k-1m miles. Long Term, I suspect repair costs will end up being equal, because battery lifetime is proving to be about 250-350k (based on Toyota hybrids), meaning by the time the vehicle is fully worn out, you'd have replaced the battery pack 2-4 times (at around 5k each) In addition, while an electric car saves on oil changes, it still needs some form of lubrication, it still needs tires, windshield wipers, brakes, body system repairs (gauge cluster, electrical, comfort systems, radio, etc), the you also need to consider suspension wear, which becomes relevant right around 300,000 miles.

In the short term, Electric cars win, hands down, they're cheaper to run per mile, but over a 20 year lifetime for a vehicle, I think ICE vehicles will tie or prove slightly better than an electric vehicle for costs.

I'll put it this way, as we own both an electric and an ICE.

The maintenance costs we've paid keeping our ICE running would pay for a full replacement of our electric motor in about 3-4 years.

The maintenance for our electric so far has been new tires and windshield wipers.

What is the age/mileage of each?

That’s just an anecdatum. I’ve spent a fraction of that on my 20-year ICE.

Maintenance cost by brand: https://www.yourmechanic.com/article/the-most-and-least-expe...

(No data on electric vehicles - oh well)

Barring a major accident, powertrain failure tends to be what actually takes a car off the road. You may not want a beat up 20 year old car, but if it runs well, someone will drive it. Yet once the engine or transmission fails it is done.

As for electric car reliability, this is a "theory vs practice" question.

In theory electric cars should be vastly more reliable due to their simplicity. Electric motors have 1/10th the complexity of an ICE, and electric drivetrains tend to be simpler.

In practice we have a lot of experience in building well executed ICE cars. Regardless of the complexity I would bet that a Toyota beats a Tesla for any test of longevity.

Not to mention that nobody makes an EV that isn't chock full of bespoke electronics. Eventually the sheer number of components and MTBF will just start biting you in the ass all the time.

My leaf has manual seats, manual headlights, no cruise control... my 10-year-older volvo has all of those, plus various transmission modes, oil control systems, exhaust management systems, engine timing controller, a whole vacuum pump control system...

which bespoke electronics do you mean which are unique to EV? and do you really think their failure rate compensates for all those ancillary systems made redundant?

You know, Teslas. Marketed to rich tech geeks resulting in a computer that also happens to be a car.

> Yet once the engine or transmission fails it is done.

One of my cousins owns a transmission repair shop, and from what he says at holiday gatherings he always has more customers waiting in line than he can ever hope to get to. Seems like some people out there are rebuilding their transmissions.

> Yet once the engine or transmission fails it is done.

This is often an irrational short-term optimization; while it's often much cheaper to get a used beater with a functioning (for now) powertrain instead of replacing engine or transmission, replacement will often last far longer and with lower operating costs and downtime.

There are fewer moving parts in an EV, so I'd expect them to last longer with less maintenance. With moving parts, it's usually all about them being properly lubricated. Batteries are a problem, but they can be replaced.

What usually kills the body is corrosion. Eventually, fatigue damage will set in and the body will crack.

Electric vehicles would have fewer moving parts so in theory it should be possible to make them more serviceable, however as others have pointed out the trend is to make cars less serviceable so it's an unlikely outcome.

>would electric vehicles last longer? Tesla

Compared to something pre-a ton of electronics? Doubt it. All of those ICs and PCBs are individual failure points and likely to have fairly limited production runs. Then add in ever-changing battery technology...

Just look at Tesla, they will not work on (or provide parts for) anything with a salvage title and look at the first roadster, completely different batteries than they currently use that if allowed to discharge 'completely' are ruined and need to be replaced.

So for an EV you probably have individual computers/chips for anti-lock brakes, traction control, parking assist (if applicable), charging, multiple diagnostic chips, transmission, infotainment, ignition just off the top of my head. With Teslas you'll also have driver assist stuff, all of the chips involved with it phoning home and collecting/reporting data back to Tesla as well. Those are all failure points using components that are likely mostly in-house and not available from OEM sources with Tesla too.

I imagine Tesla has some control over your vehicle too if you attempt to circumvent some things not unlike how their power wall will disable itself if it can't contact the servers within a relatively short period of a few days (I believe it's a few, it might be 24 hours) so if they ever for some reason go out of business that may severely impact usability. The original roadsters are a different battery than being used in current-production Tesla vehicles and I doubt in 10 years they're going to go "Sure thing, we can custom make the 2 of you that are still driving your roadsters new batteries".

How often is IC & circuit board failure a thing in cars although? I've had 20 year old cars, and the only components that failed in that category were micro switches on boards for windows and the ignition, and I was able to buy new replacement parts for them. Another common failure point in car electronics are connectors & cables, another thing that doesn't seem that hard to replace or have clones made by chinese manufactures.

>How often is IC & circuit board failure a thing in cars although? I've had 20 year old cars,

The stuff in a car coming off the line today is generations more complicated than what was being put in a car 20 years ago.

I never had problems with anything electrical related until owning a 'modern' carn, my 2013 impala which has had multiple faulty sensors, a wiring harness that would randomly turn stabilitrack on and off while driving, would randomly fire abs while breaking, throws off 3 check engine lights from various emissions systems any time humidity is up, etc.

N=1 but most of the issues I've had with my Impala Chevy has had across multiple generations of multiple vehicles in the past decade from cars and trucks. One of the emission sensors that is faulty in my car is used in at least 2 generations of 3 different models and a search of one of the codes it throws comes up on a dozen plus forums.

A quick google on just ECM/ECU/PCUs make it seem it's common enough for them to fail in vehicles and those are usually programmed to your VIN. Looks like corrosion from moisture, cracked traces, vibration damage, etc are all common causes.

Hell, even TPMS sensors fail regularly enough and some of those can get a little pricey and will throw codes until you replace them.

I think your issue is you got a GM car, which has had a decades long reputation for some of the worse reliability and quality issues.

Except for a quick Google as previously stated brings up every manufacturer under the sun.

Modern vehicles are full of cheaply made electronics that fail.

Another quick Google query shows that the average age of a modern vehicle is 11.4 years. Sticking with Tesla, the vehicles are only warrantied for 4 years or 50k miles and the batteries and powertrain for 8 or 100-120k miles

And as I stated previously they've already completely changed their battery tech once meaning the supply chain for new batteries for the original Roadster is effectively non-existent and given they are now 10 years old, they are outside of warranty and Tesla has zero obligation to manufacture replacement batteries, with ICEs it's extremely unlikely diesel or gasoline will suddenly be controlled by one supplier and be cut off from the market.

With ICE cars you have multiple people manufacturing secondary market parts (even for stuff like ECUs), with the most well known electric car company you have the manufacture as the only one making parts AND they do not sell them to consumers and they will not work on anything with a salvage title.

Working on an EV is also not really something you can do yourself if you do have access to parts. ICE vehicle you can realistically work on any part of the vehicle yourself, at home, with rented tools and a repair manual or YouTube videos from rebuilding an engine or transmission, replacing ball joints, changing brakes, replacing fuel line, completely rewire the vehicle, anything.

Sure on an EV you could change a ball joint or a suspension, but you can't work on the powertrain. You can't work on the power plant. You can't really work on any of the wiring either. The most important parts of the car pose potentially fatal shock if start monkeying with them.

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