Lithium-ion cells are remarkably finicky and fragile. There's no clear cut-off that demarcates "over-charged" or "over-discharged", you're just increasing the stress on the cell. A highly stressed cell has a much shorter cycle life, so there's a tradeoff between durability and capacity. The 0% and 100% you see on the charging icon are essentially arbitrary lines, chosen by the product designer to best exploit this tradeoff.
Drone racers will often charge their cells beyond 4.3v and discharge them below 3.2v to eke out every last joule of energy. These cells will lose 20% of their capacity within a few dozen charge cycles and might fail catastrophically due to dendrite formation. A perfectly reasonable tradeoff in this application, but a disaster in an electric car.
For obvious reasons, electric car manufacturers lean strongly on the side of durability. Nobody will care about an extra 20 miles of range if their battery fails after 40,000 miles. Consumer electronics manufacturers started using more conservative battery management profiles when non-replaceable batteries became the norm - by sacrificing a bit of capacity, they could double or triple the cycle life of the battery.
Note: this explanation is grossly over-simplified in the interests of brevity. Battery chemistry is ludicrously complex.
There are some advantages in having a s/w locked down battery rather than a physically limited battery. Since the battery charges slower when it is above 80% capacity, you can recharge to "100%" much faster with a software limited battery. Similarly, charging to 100% is supposed to cause more battery wear, so in a real 75 you don't want to do that very often. But in a 60, its no problem, since 100% is really 80% of the physical capacity.
So doesnt that make this update a little late and kind of useless?
The evacuation order was days ago. People have already left their homes--where they would have charged their cars. They already made it to where they were going on the 60kw charge they had or they didn't. The hurricane has already reached FL. http://media.miamiherald.com/static/testdir/weather/storm-ra...
This is a thing in OBD2 ICE cars as well and has been for years, particularly the VW series of cars in the 2000s. The GTI had most of the same parts as the Golf but the GTI had an ECU "tuned" to maximize performance.
Hondas were not that much different, though not as egregious. The rise of Hondata and scavenging JDM parts overseas is a testament to that.
"Software" just feels different. But it really isn't, whether it's firmware (ECU) or a few extra holes/different tolerances in the machinery.
In the case of the tesla, they're taking something good and just tuning it down.
I wonder how people would react if they did this with the next iphone - i.e. it only charges to 80% unless you pay for an upgrade.
I just wish I could pick these modes for my phone, especially if it's a non-repairable battery. My Lenovo laptop actually has something like this - it puts the laptop to sleep at 20% and only charges to 80%, unless I choose otherwise.
In the case of the Golf/GTI, there wasn't. The hardware is virtually the same in both, the only difference was ECU tuning. This is the same as the Tesla, it's not tuned up or tuned down... it's identical, just rolls off the line with a different body, accessories, and ECU.
>>In the case of the tesla, they're taking something good and just tuning it down.
That's exactly what VW and car makers have been doing for decades. And Intel, AMD, Western Digital....
>>I wonder how people would react if they did this with the next iphone - i.e. it only charges to 80% unless you pay for an upgrade.
Probably about as poorly as this is being received, even though it's been going on forever.
Tesla gets to sell a car it otherwise wouldn't get to sell, and a consumer gets a vehicle they otherwise couldn't afford. Why is that lame? That's capitalism.
That's a fundamental problem we've been having for a long time, then - you own the device, they own what you can do with it.
It's the very same issue a lot of us have fought tooth and nail for, for the last decade and a half.
Edit: someone replied - then deleted - that effecitvely this is a free market issue. I agree with that, and I by no means think that government needs to get invloved. Still, as a consumer of such devices/cars, I still feel uneasy (to say the least) about this scheme/business practices. It's "lame" for the reasons I outlined.
[0] https://motherboard.vice.com/en_us/article/xykkkd/why-americ...
It's lame because the value change is one-sided.
The value is being adjusted by taking away options from a good which has the same intrinsic material value as another to change the market value of the good.
It's capitalism, sure, but it's not one of the better parts.
I don't know the details of Tesla's batteries exactly, but I'm pretty sure they're just use a ton of 18650s. If too many of them won't hold a charge, then instead of fixing it they can just call it a 60 rather then a 75.
https://electrek.co/2016/07/26/tesla-upgrade-software-limite...
That's a bit silly. I suppose in someways it is nice for the consumer that they have the 60kwh version if they're basically selling it close to a loss with the hope that you'll pay for the battery upgrade, but obviously it begs the question why the 75 model can't just be the same price.
Because Tesla would make less off of each 75, which is no good when you need cash to expand operations. Have to squeeze every dollar out of each sale, manufacturing and R&D costs money!
There usually isn't anything notable about a business approximating a rational economic actor.
Definitely not true. The parts are the same, the support contracts are not.
Price discrimination is bad for consumers.
The vast majority (in the US at least) of price discrimination instances are cases where anyone is free to choose the cheaper option. Rich people can clip coupons too, they just decide it's not worth it for them. Heck, the whole reason for a Tesla Model 3 and Model S is price discrimination. I think it's a great thing I'll be able to get a Model 3 while richer consumers can choose a Model S if they care to.
Let me give you an extreme example.
Imagine that a company perfectly knew the exact maximum amount of dollars that you personally are willing to pay for their product. Then, they offer you that product for 1$ less than your maximum.
This is called perfect 1st degree price discrimination, and results in ~zero consumer welfare, because consumer welfare is the difference between actual price paid, and max willingness to pay price, which in this case are both ~equal to one another.
Alright, then there is no 60 kWh version of the car. Is that a better version of capitalism?
That's implicit short-term thinking which I find strange given the speed at which such technology improves nowadays.
Even assuming the government made a law against artificial software lockdown punishable by death, this luxury vehicle would still come down in price and improve in quality well within the lifetime of most of the people who are currently drooling over it.
That's not an argument for making such a law, just a refutation against what is probably a false dichotomy between car and no car.
Price discrimination is horrible for consumers.
Why? 75 kWh version requires a more intensive support contract, more warranty repair, and more service.
Easier to validate and build one powertrain on the assembly line than 2-3 variants.
but I don't know of any ICE models where the difference is solely software that locks features down (or, as you said, drilling a hole somewhere to limit functionality). They may share parts like bodies or engine blocks (not sure, I'm not a mechanic) - but there's a lot of additional hardware that makes it safe for them to beef things up via software.
not sure though - can you think of any two ICE models where difference between the two is solely locked down via software? or the only difference is a hole drilled in a cylinder, etc etc. It may exist and I'm just not aware of it.
https://www.whatcar.com/bmw/1-series/hatchback/review/on-the...
b) I'm on mobile, cannot find exact models now, but yes, there were two engines having the same engine block&head, acessories, turbo, powertrain and were only tuned differently in ECU. Not sure now if it was for the same model of the car itself, though, maybe it was used across different model series. And a pretty common practice in European diesel cars with average power, loading ECU maps from higher versions - although often, the car would have smaller brakes or less Nm rated powertrain.
Diesel trucks tend to be like this too. If I recall they put the same 7.2L engine in a bunch of F-250 to F-550(although there your also paying for better built frame/suspension) models.
This is done all the time in other industries - aircraft engines are derated, SSDs are over-provisioned, all to preserve longevity. It's also done with CPUs, perfectly good cores disabled in lower performance models.
It's annoying, but on the other hand it would be kind of neat to avoid paying for the upgrade until the first day you find you need it. Maybe you never do?
What’s wrong with blurring the lines between hardware and software? We do in app purchases all the time, and if standardising hardware across all product levels makes things more efficient anyway, why not?
https://en.wikipedia.org/wiki/BMW_N47
There are two basic versions of that engine both have four cylinders, a 1.8L and a 2.0L, that's only a difference in sleeves and pistons but it is not just a software change.
There is no 2.3L version of that engine and I'm not aware of a 323d.
The next level up is a six cylinder version:
https://en.wikipedia.org/wiki/BMW_M57
Which comes in three different displacement variants.
For a couple hundred quid you could "chip" the engine to match or exceed the rated power of the BMW version. They even installed it in such a way that the chip could be removed before you took it in for a service so as to avoid warranty concerns etc.
it just seems perverse in this situation though. vehicles have more of a 'life and death' component than a digital camera
As pointed out multiple times in these comments, Tesla is not the first company to do this. VW, Honda, and many others have been doing this for decades.
Does anyone know exactly how this is done? does the battery just never charge up all the way? does it claim it's empty when there's actually more charge left? Are some of the cells locked down and just don't charge? How does it impact the health of the battery (since not being able to charge or discharge completely would presumably affect the health of the cells)