this post was submitted on 06 May 2024
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It’s tricky. It’s not like BMW locking heated seats, a trivial feature, to nickel and dime the owner out of $300.
Reducing the battery capacity severely alters the value of the car possibly dropping it into the range of more budget conscious buyers.
There are benefits too. Less wear on the battery by not using its whole range, faster charging to “100%,” and more potential value when it comes time to sell should the buyer want to unlock the extra range.
Leave it to Tesla though to bungle the PR and completely lose the narrative.
Yes it is; it’s exactly that.
Or they could not reduce it for the same production cost. No money is saved by tasking an employee to develop the battery nerf.
There are no benefits. You could simply unplug at 80%.
You misunderstand, having a larger battery that is not used to full capacity makes it last longer. If you unplug at 80%, you need to have paid the extra price for the bigger battery, if the battery size was actual physical battery.
There is no “larger battery”. It’s an identical battery with different software limitations on the charge level.
No consumer benefits from artificial limitations being imposed on them like this. It exists solely to extract more money from consumers. The fact people are defending this blows my mind.
No we agree on that, but when the market is so they can charge more, you still benefit getting the car cheaper with 80 Watt than an extra production line with a 70 watt battery. I agree it feels like cheating.
I'm not defending the practice, but you are arguing from a false assumption that the company would choose yo sell at the discounted price, instead of only having the full version at full price in this kind of cases.
If the choice is between making a model with an actual smaller battery that cost the same to make, the customer is actually better off getting the bigger battery without being able to use it 100%
There is no such advantage in the BMW example. Which was kind of the point.
Let’s just say it’s 50% battery capacity and range for simplicity.
As each cell dies, it can use another cell to replace that one, it would effectively double the life span of the battery.
That's...... not how battery packs work
That’s actually how the majority of batter packs operate, they have a margin of cells to replace when they start undercurrenting. It’s not quite THAT simple, but it’s not also that difficult when every pack has electronic controllers in them now.
How do you think they were able to do this battery capacity limitation if you couldn’t do something like that…?
No. The packs aren't like flash storage where they have spare blocks to use when one block wears out. Essentially switching in something that wasn't used at all before.
The cells are all connected physically, being charged and drained. They do not connect and disconnect cells when wear occurs. They have software limitations on how far to charge and discharge (at what voltage and c rating). Yes, a larger pack will last longer if the charge/discharge cycles aren't as "deep". But no, they don't have spare cells just to cover wear.
You realize you can also use a microcontroller to completely shutoff cells so they don’t get used until one dies yeah? There’s multiple tech in these packs now.
Some pieces of equipment allow you to put two batteries in it, so when one is depleted it automatically switches over to other one. Same kinda concept, just done at the cell level.
Think of a battery pack like a backpack, it’s lots of cells in series, to make larger batteries, you make the backpack larger and hookup more cells. A fancy controller can control which individual cells are active. Or even think multiple backpacks, now linked together.
No. Handwaving a microcontroller doesn't fix it unless you have two high current contactors per cell, and multiple intermediate busses and contactors, it's not going to work.
That's going to add a ton in transmission complexity, and weight, that doesn't really benefit the battery at all. Along with the fact that cells should be balanced in wear and cycles. It just doesn't make sense.
Again, most battery packs already do this. It’s the nature of the natural design it of it. A pack is collection of cells, wired together in different configurations for V and A…. It’s already a massive collection of tiny cells put together and put together and put together, and put together, put together, until you have what you want……
Huh? How so…? Wires are negligible weight and what complexity? It’s already wired and it’s just a micro controller an d programming….. so what added weight? The wires are already there and are only a fraction of a percent of the total weight….
Yes it absolutely benefits the battery…. it can double the life as previously explained, that’s a massive boon mate.
It’s okay to be wrong.
Most packs have only 2 contactors. Not 2 per cell. The only way to have spare cells that are not in active use all the time is to physically disconnect the cells from the rest of the pack. The only way to do that is to have contactors at each "end" of the cell, or cell pack, that you want to switch in and out.
Car packs are ~360-800v nominal depending on the car/pack. To get to those voltages with the normal cells (~3.2-3.7v nominal)you need between 95 and 250 cells in series (wired one to another directly, all the power goes through all the cells).
Let's do an example. The simplest pack possible. A 95s1p meaning 95 cells wired negative to positive in a single line. A contactor at each end to cut power to the car for safety.
This is the simplest pack. Also the lowest range and worst for cell wear.
So say you want to "double" the range? You "simply" build an entire separate pack, and drop it next to the first with it's own set of contactors, right?
But in that case you have doubled the amount of interconnect bus in the pack(the wires to get the high current out of the battery), as well as contactors.
You could get to the same power storage (range and longevity) by making a 95s2p pack with one set of contactors.
So instead of 2 lines of cells, you connect each cell to it's partner with a small piece of wire then connect that to the next cell in the pack.
This means you don't need the extra long wire from the back to the front of the pack for the second set. The tradeoff is you can't physically disconnect the second cells, but you don't need the weight and complexity of extra contactors, and the long wire for second cell set.
So what's the actual benefit of physically disconnecting the second set of cells?
When one battery dies in the 95s1p pack, the whole pack is useless, as all the power from the remaining 94 cells must travel through the one high resistance cell.
In a 95s2p pack each cell only has to take half the current of the entire pack (improving as you go up in parallel cell count).
You would be able to run one 95s1p dead, then switch to the other and keep driving till that is dead. But the efficiency of that is actually less than you get if you just had one 95s2p you ran from full till dead.
So again, being able to physically disconnect some cells in the pack only adds weight, complexity, and risk.
The Tesla car with "less range" that can be "unlocked" is literally just a software setting that limits the charge/discharge voltage of the entire pack, not switching in and out battery cells physically.
So... As you said
That’s a lot of words to say, what you said is absolutely how battery packs work to limit total failures.
Can you provide a link to a battery pack design that is one total massive cell like you’re saying instead of multiple individual? Other than some thing like a AA or AAA battery….
How much do you think a length of wire weighs compared to the weight of the pack? You’re making to seem like it will add 30% weight here or something, the weight is negligible, why are you even mentioning it?
Not sure where you're getting "one total massive cell" from anything I wrote.
Every pack is made of a bunch of smaller batteries. You can't get 400v without batteries in series, from batteries that only make ~3v.
Just saw your last paragraph edit. It's a car pack, every ounce matters, and doubly so when it only adds complexity, reduces efficiency, and reduces reliability.
And an estimate of weight of the extra interconnect.... let's say it's 8' from back to front of the pack, a 350v pack and a 250kw motor. This means minimum of 715 A. Busbar that is rated for 700-800A @30c rise has cross section of 1/4"x2". For the 8' length that means we have 48in^3 of copper. That is ~16lbs of copper alone. Not counting the contactors, insulation, etc.
So 1% of a 1600lb pack? Wow so detrimental….
It is, especially when the choice that leads to that extra weight is less reliable, less efficient, and more costly. All things you don't particularly want in a car
So let's get back to the real discussion on how the packs actually work. Can you explain how a microcontroller is supposed to put cells in and out of the circuit?
It kinda sorta is, but not exactly.
Yes, but perhaps some money is saved by not having to manage multiple production lines for multiple battery capacities and also having to predict how many of each capacity is going to sell so you're not stuck with cars nobody wants?
Right, after you just paid more for battery that you've decided not to use. The benefit is that it's cheaper for the customer.
It’s only cheaper because they inflated the price from a limitation they created. There is absolutely no reason to limit the battery capacity in software in this manner other than to create an artificial divide to upsell people on the “”higher”” capacity.
TIL Tesla has a 100% monopoly over the electric vehicle market space.
Tesla is offering a wider variety of products at more diverse prices to try to better fit the needs of a larger portion of customers. They must have determined that it was cheaper overall to do it this way rather than physically rip the batteries out of the vehicles or they wouldn't do it.
I mean, isn't not offering a cheaper version at all already upselling? When the F-150 Lightning came out, people had a really hard time finding the standard range version because dealers didn't want to sell a lower trim version of the car with lower commission.
Or, you know, just keep the capacity the same and lower the price without imposing a battery nerf. It costs the same to make. The only reason the nerf exists is to extract money from consumers.
You are not required to purchase your vehicle from Tesla. I mean, we're butting up against the primary tenets of capitalism here. I'm a socialist personally, but if there's one thing that capitalism is supposed to do well in theory, it's find market efficiencies. Tesla appears to have found one here. If anybody else could sell a non-software locked smaller-battery version of a similar vehicle for a lower price, people would buy that one instead.
If I own the car then either those are all my cells or someone else has abandoned their property in my car.
You don't have to buy the car. People aren't getting conned here... They would buy a more expensive version of the car with a higher range if they thought that would suit their needs.
If it's a profitable decision then it has the potential to become the de facto standard, so simply not buying it isn't enough.
The manufacturer using software to lock use of hardware in people's own cars is an attack on ownership rights.
When it comes to things that are trivial to include but locked behind exorbitant paywalls (i.e. heated seats), I agree.
However, range/battery capacity is the primary price differentiator for EVs and also the primary cost for manufacturing. Finding a way to offer options that suit the needs of different people at varying prices just allows more people to enter the market.
I feel like it might be nice to have a sliding scale of ranges available for people who have a sliding scale of needs. If I need a second car strictly for my 20 mile commute, it might be nice to have an option to pay less for 100 miles of range over 200. And I assume if a market is established for low-range EVs, manufacturers will compete with each other on how to deliver that for the best price. Perhaps if the market is large enough, Tesla will find it better to actually remove the extra batteries and put them in other cars.
If manufacturers made parts available for longer (or perhaps at all in some cases?) then 2nd-hand cars already make for a cheaper option.
I believe artificially limiting hardware is an unacceptable for a health society because proprietary software gives the developer power over their users. Even people with good intentions will be tempted to use that power at the user's expense. A software update could suddenly make that 20 mil commute no longer possible unless you agree to pay more for some subscription, or accept a new terms of service where you agree to forced arbitration if you don't want to lose access to even using your vehicle.
Agree here, but that's a much larger issue than just this particular pricing structure.
Is the artifical segmentation pricing structure possible without lockout software? Software has wide applications but in the end this is about freedom.
I would like an EV but I want an old dumb car converted as I don't want the modern car computing systems (unless there's one that runs a free OS).
You are 100% right it improves the lifespan, and when selling it, a battery in better condition makes the car worth more.
I think somehow some people misunderstand your post? Or they don't get how it can be an advantage to have a bigger battery than you pay for?
Mind you I don't condone this business model, which to me feels like cheating.
It's funny how frequently this business model is used in the digital space, but when it comes to physical hardware, people freak.
Like look at movies. Does anybody really think it costs substantially more to deliver the 4K version of a product over the HD version? Everything, Everywhere, All At Once is $12 on Blu-ray on Amazon. It's $20 on 4k UHD.
The movie was mastered at 4k or higher, so why not just give you the UHD version with the Blu-ray version? The physical disc can't cost more than a few cents to manufacture.
It's because some people have decided they don't need 4k and are happy to take a shittier version of the product for a lower price.
Don't get me started how much people hate when content is included on the game disc locked behind a paywall yet somehow have less of an issue when there's day 1 downloadable content also locked behind a paywall.
None of those other behaviors you describe are any less shitty. “Look, Tesla is doing the same shitty things as other corporations, they’re not so bad!” What a terrible argument.
For the record I pirate my content for the reasons you describe; I also don’t fuck with AAA games with day 1 DLC or paywalled content. Those get pirated or purchased on a heavy discount later.
Got any compelling argument as to why this software nerf should exist?
Sure:
It's cheaper to manufacture and maintain a single version of a product. It's cheaper to ship and store a single version of a product. It's also easier to adapt to quickly changing market needs if you don't need to spend six months spinning up a production line for a different version of a product.
Also, the existing market for low-range EVs might not be large enough to justify the expense of maintaining a separate line.
If there is competition in the space, it's safe to assume that some portion of these savings are passed on to the customer to better edge out competitors over price.
If you want to be very charitable: wealthier people who can afford the full-range version are partially subsidizing the lower range (tighter margin) version for more budget-conscious consumers.
Edit: Especially when talking about the structural battery of the Model Y, it may help to understand how these packs are made: https://www.youtube.com/watch?v=ozesI3OZEG0
The batteries themselves maintain the rigidity of the pack. If they removed some, they'd have to slide some dead weight in there. Also, once the packs are sealed, it's impossible to remove a portion of the batteries without destroying the pack. These are designed features developed to reduce the overall weight and cost of manufacturing the pack.
If they can sell the same battery, just one has a software limitation, they can just forgo the limitation altogether and sell full battery capacity models at the reduced limited capacity price. The only reason this limitation exists is to juice customers and it’s bullshit. They are going out of their way to make a product worse that costs them exactly the same regardless of if the limitation is there or not. You cannot convince me that the software limitation they impose is anything but hostile to consumers.
I mean, they can just give the batteries away for free too, but most businesses have a vested interest in making money. In Tesla's case, they also have an interest in paying back the massive investment it took to get the first car off the lot.
Saying "they can sell the same battery" is ignoring the fact that they would not be able to sell the limited capacity version of the battery if nobody was buying the full capacity version.
Perhaps typical people can more easily understand how a physical device might work. People probably understand gears and electricity more so than "software" (never even heard of source code or binaries).
That just means they could be selling the full range version cheaper. You're getting the same hardware. It's insane. Not "tricky".
No. The additional price of the full-range version is partially subsidizing the lower priced version. People are willing to pay the current price for the longer range version, why would they lower the price?
That makes it even worse!
Why does that make it worse?
Because they are over charging people for the same hardware. Everyone is receiving the same product except for the fact that the cheaper one is hamstrung by an unnecessary software change. If it wasn't for that all these cars would be identical. If they can sell it cheaper then do so. If they can't don't. If you want to have different price tiers make a version with more actual features. How are you not seeing this as a bad thing?
Because there is no inherent link between the cost of manufacturing a product and the price at which it’s sold.
So if Tesla develops new technology that allows them to produce cars cheaper, should they be required to lower the sale price of their vehicles?
No, they price them based off tons of factors. I understand that. What I'm saying is they've demonstrated that they can sell the vehicle at that cheaper price point so do it. If it only works because the people paying more are subsidizing the cheaper ones then the price should probably be somewhere in the middle. When they are selling two identical vehicles those should be the same price. What they are doing is the same as if they were selling a "headlights" version and "no headlights" version and accomplishing that by just smashing the headlights on the latter as they roll of the line. It's dishonest, stupid, and wasteful.
They’re not destroying anything. The car can still be upgraded by either the current owner or the next one.
Ironically, you’re advocating for going through the effort of physically removing batteries to sell at a lower price. That’s closer to your headlight analogy. The car was designed to have a specific battery size, and the equipment is already built to make that size. It is not easy to physically alter the batteries at scale.