Usually for these things nominal voltage is the standard. For lithium batteries that’s typically considered to be 3.7v/cell. From that perspective the model 3 is considered to be a 350v platform.
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Model 3 Highland Performance/Plaid Speculation [Car announced 04.23.2024]
- Thread starter Daniel L
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Yeah, volts on lithium are weird due to the broad changes over state of charge and load.
The Model 3 is a 96S architecture. At 4.2V (full charge) this is 403V. At "nominal" 3.65V this is 350V. Dead (3.0V) this is 288V. But the Model 3 motors are rated at 320V which is why I used it.
Plaid is 110S architecture, so it's 462V / 402V / 330V.
So at nominal a Model 3 is 350V and Plaid is 400V.
Note that at a fixed resistance, increasing voltage from 350V to 400V (14%) increases power by the square (30%).
What Voltage is the Model S LR? Is it the same battery as the Plaid? What motors does the current LR use?
According to the EPC, there is only one battery assembly for all S/X cars since Feb 2021:
The motors are different:
Front: Parts Catalog
Rear: Parts Catalog
This all aligns with the Model S manual as well:
Model S Owner's Manual | Tesla
Learn about the various subsystem components and their specifications in your vehicle.
www.tesla.com
It doesn’t matter what “people are asking for” I’m talking about one specific thing which is an acceleration boost on the P. You’re arguing with a straw man bringing up what everyone else is asking for. I can do all the “differentiating” I want with my current P3D; body kit, rims, brakes, tint, lights, wrap etc… there’s one thing I can’t differentiate and that is the acceleration. It is the same as every other P3D. So that’s what I’d prioritize differentiating. And yes I meant rotor. I never said it needs to be a model S plaid just a little faster than the current one to set it apart. I don’t mind factual pushback but you include a lot of speculation in your facts even if they are reasonable assumptions.
And honestly, It’s DOY 311 if you think 120 posts this year is a lot then don’t look at your count. It’s just a weird comment to make anyways, you basically admitted to taking the time to do an advanced search and count my posts based on an off hand comment I made to express my frustration with the attitudes I encounter on here. Do you think your actions support my frustration or serve as a fact check to it
? Did you graph it over time to see how this year compared to previous years? Did you look at it monthly to see if I’m trending up or down? Do I have long gaps where I stay away for a while then come back, get frustrated, then stay away again? How do you define “rarely”? Is that the kind of factual pushback you’re doling out?I'm still trying to understand voltage/architecture. Why isn't a Taycan with it's 800V architecture significantly more powerful than the Plaids? Seems like it would be very easy to just wire batteries in series instead of parallel for extra output.
Each cell is still more or less the same power output. Assuming you've got the wiring to handle the higher current at lower voltages, the total power output for a given number of cells will be similar (efficiency losses due to lower voltage notwithstanding).
Gauss Guzzler
Safety Score = 42
Exactly. For a certain *quantity* of battery material, you can get a certain amount of power. It doesn't matter if they're wired up in series or parallel for 4 Volts or 4 million Volts, the resulting power is the same. Nothing's free in this world.
Part of this deception is inherent, people just think mo' is better.
Part of it is inevitable. Makita uses 18650 cells just like anyone else so their 18V cordless drill is inherently more powerful than the 12V version - not because it has more Volts, but simply because it has more battery cells.
And part of it is unintentional. Engineers choose higher voltage systems to keep the wiring size down as Ohm's Law V=IR shows that you can trade current for voltage to get the same power thru a smaller (more resistive) wire. Higher voltages require less copper but more insulation so there's an optimum balance, which today seems to be around 400-800V for EV's.
Part of this deception is inherent, people just think mo' is better.
Part of it is inevitable. Makita uses 18650 cells just like anyone else so their 18V cordless drill is inherently more powerful than the 12V version - not because it has more Volts, but simply because it has more battery cells.
And part of it is unintentional. Engineers choose higher voltage systems to keep the wiring size down as Ohm's Law V=IR shows that you can trade current for voltage to get the same power thru a smaller (more resistive) wire. Higher voltages require less copper but more insulation so there's an optimum balance, which today seems to be around 400-800V for EV's.
Plaid has 3 motors and the Taycan has two. Just because you can produce a lot of power doesn’t mean you can utilize all of that power. The power has to have a place to go.
The most significant reason for Porsche having an 800V architecture is for charging - for input current to the battery pack. Not output.
You can visit Porches' website and easily find this explained in detail.
You can potentially charge a Porche much faster than you can charge other EV's IF and only IF you can find infrastructure that will allow you to do so. I feel safe in saying that you will be hard pressed to find many 800V charging infrastructures out there as they would be significantly more expensive to produce and may be ineffective in cost. It's not even at Porche dealerships. I was just at the Porsche dealership in Naperville Il and they flat out said that the dealer owner didn't want to flip for the cost of it. I was thinking that Porsche would want to pay for it and promote it...but I digress again.
The other more pronounced reason is to reduce the diameter of wire needed to deliver the current. Elon stated on many occasions that the cost of wiring in each vehicle is significant as it pertains to the cost of each vehicle. One of the reasons that Elon indicated that Tesla is moving to a 24V in fracture in their cars is the reduction of wiring size/cost. The larger the voltage - the smaller the current and wire size needs to be to deliver the same power. One of reasons that power lines across the US run voltages in the thousands is to reduce the necessary wiring size and current(amp) size ( as well as compensation for power loss over distance - but I digress).
At first Porsche was charging their battery pack at 800V (fast) but discharging (slower) at much lower which brought them in line with everyone else. I don't really care for Lucid but the CEO did a great job of explaining their battery infrastructure as it pertains to the motor design. There is a video. Tesla has done the same thing; however you would have to listen to a Sandy Monroe or Weber Auto for an Indepth explanation.
As many here have said - just because you have higher voltages and/or lower current - the end game might turn out to be the same depending on the design.
There's quite a few 800V chargers in Europe. Of course like anything, this is all a bit of a mess for infrastructure and charging speeds when you plug a 400V car into 800V or vice versa. It's like the Betamax and VHS or DVD-HD and Blu-ray where eventually one will win out. Pretty sure that's likely to be 800V so sooner or later Tesla will probably need to switch.
This is just not right. At sub-kV voltages, insulation thickness is about mechanical strength, not standoff voltage. Look at this table of insulation tickness. It STARTS at 5kV and only needs 2.3mm at 5kV: https://www.anixter.com/en_ca/resources/literature/wire-wisdom/insulation-levels.html
As it says:
No EV engineer has ever worried about the trade of the amount of metal vs the size of insulation. The insulation is identical on a 400V wire and an 800V wire. Plus, even if it wasn't, you can stand off the wires from one another farther with other mechanical separators, you don't have to rely on the insulation on the wire for all of your distance.
If you look into why 800V architectures weren't the first ones used, it's because of the semiconductors. Before EV's were popular, most power switching FET product lines maxed out at 600V, which leaves about 400V usable with reasonable design margin. In 2012, you flat out couldn't go to industry and just build a 800V EV with off the shelf electronics. But you could if you did 400V, so that's what Tesla did. And this applies just as much to the superchargers as it does to the onboard drivetrain stuff. It's only since 2018 or so that the semiconductor world has seen a market for 1000V parts that makes it realistic to build 800V cars without a ton of NRE on custom parts.
800V is not just about ohmic losses in wires. You have other things like switching losses and non-linear voltage drops in semiconductor junctions that also benefit higher voltages.
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Cybertruck is moving to 48V, not 24V. Once you decide to throw away 12V and being able to buy from standard automotive, you might as well go as high as you can. 48V is widely accepted as human safe- meaning you can touch/grab 48V with any part of your body and not be physically harmed. OSHA considers 50V or above as harmful, so everyone goes to 48. This is why Power Over Ethernet is 48V also.
This doesn't make any sense. The battery pack doesn't care about "input current." The individual cells are what charge. If I take a 100S100P pack, that's a pack with 10,000 cells, 365V at the pack level. If I put 250kW into this pack, I need to do it at 365V, 685A. Each cell during charging is at 3.65V, and 6.85A.
If I do this with a 200S50P pack, I have 10,000 cells. The pack is at 730V, and 250kW is 342A. But the cell current is still 6.85A.
The cells have no idea what voltage the pack is at, and don't care. And it's the cell chemistry that limits charge speed, not the pack design. If the pack design mattered than we'd say that charging an individual battery would take days because it's a 3.65V architecture. But you can generally charge a free standing cell faster than a cell in a pack due to being able to thermally manage it better.
I see the same dumb stuff online like "800V charges twice as fast as 400V" which is complete ignorance. The cells are the limit to charge speed, not the charger.
Does anyone really know why you can charge an 800V pack faster than a 400V, assuming you have the identical cells and number of cells in the pack, just in a higher S lower P configuration? Watts are watts, and each cell has the same voltage and current, so it generates the same heat under the same charge speed. Even weirder is that when you look at charge graphs most 800V architectures charge faster by maintaining the high power phase for longer, which is completely about the cell chemistry.
Before you answer thinking you know, read this thread, where this was discussed and nobody actually knows: 400 volts vs 800 volts charging speeds question
There is a very good chance that the answer is that 400V and 800V can charge equally fast, but that the current 800V cars have superior cooling, cell chemistries, or they keep a ton of overhead in the pack rated power (Porsche does this for sure). But instead of trying to market that, it's easier for the marketing departments to sell "800V is better" than explain why when the real reason has nothing to do with 800V (at least for charging speeds).
And of course the final irony is that in a real car in 2023, 800V is slower since most chargers can't hit 800V at high amps.
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I don't do back and forths on forums however there is a lot here that needs to be responded to.
Firstly Yes, I do know how this works and so does Porsche.
The charging infrastructure of a car can be varied in many ways. It's all up to the BMS systems/Temperature management/etc. and how they are designed. I never said it was up to the batteries and NO....Tesla's battery packs are nothing like Porches. They are NOT the same.
There is a reason why Tesla's battery pack pre-conditions before charging. I give seminars on thermal management as it pertains to electron flow.
The discharge of a battery cell/pack also varies as much as the charging. I am not trying to get into the weeds of technicals about how this all works however I can. I'm trying to be general as this isn't the topic of this thread.
These things I definitely know about here. If you want to talk offline of this thread, I am more than willing to do so or you can come to one of my seminars on this subject.
Seriously people acting like uprated motors cost 10k when Tesla has been known to throw higher spec motors in lower spec cars all the time. If it was that big of a cost difference that would never happen.
The way I read this, I was right that the 800V vs 400V isn't the important part. It's more fundamental to overall pack design, and a cell doesn't know or care what the pack voltage is. 800V and 400V is just marketing.
This is a money/weight optimization, not a technical limit on battery charging rate.
You sure have a lot of "you can go find it somewhere else" without actually citing your sources. It's not very helpful to the discussion. Care to provide a single link to any one of your references? I read everything I could find on Porsche's site and it convinced me that 400V vs 800V has nothing to do with charge speed, and was pretty empty on technical details.
Are your "seminars" free? If not, do you promise me a full refund if after listening you have not actually explained how an 800V architecture fundamentally allows an individual battery to charge faster than 400V does, assuming the charger can deliver the same peak watts, the batteries are the same, and the pack has the same capacity?
FYI, if we're gonna throw around unsubstantiated technical expertise one-upsmanship, I design electric aircraft for a living, am highly involved with battery management in thermal, electrical, and chemical areas, and am well aware of the multitude of tradeoffs with lithium chemistries. I give "seminars" to the FAA on the future of electric flight. So feel free to get into the technical weeds with me of how 800V vs 400V fundamentally changes how fast you can charge a vehicle at the cell level, because I can't figure it out. What I can figure out (as I posted earlier) is that more advanced overall architectures could support faster charging, but this has nothing to do with the pack level voltage or wire sizes.
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If you aren't going to post me correctly.... then I bow out of this discussion
my seminars are for college credit.
I'm here to learn about the technical aspects and details as they're fascinating. It'smuch better than the back and forth speculation without any expertise. If you'd like to chime in, I'm sure I wouldn't be the only one interested.
Thanks Daniel. I agree with you. You are too kind.
I'm going to bow out of this discussion. My apologies.
There is only one way to stop what's happening here.
There is one thing I have always been excited about though. I remember when our cars didn't pre-condition the batteries before charging. The charging times were much longer. Then our testing showed that we could effectively reduce the charging time with temperature management alone. We started heating up the pack to 212F then chilling it down as soon as the charging started thereby reducing the time at the charging station without any adjustment in battery chemistry. It was exciting to see those Ions intercalate so quickly. I know that's nerdy stuff but...anyway.
You can see this for yourself with a free app called scan-my-tesla. There is a device you need to plug into the CAN buss (simple to do) and watch the battery temp rise when you set your car to have a destination of a supercharger. If you have a dual motor vehicle...you can also see the front motor disengage and start spinning to create heat for this exercise.
Its these kinds of things that afford themselves ONLY to Tesla as the thermal management of everything feeds itself through the same device using things like heat exchangers and the like. Other OEMs didn't seem to go this route and have separate thermal management systems for each subsystem bringing up the price of the vehicle as well as repairs. Anyway.
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Has never once happened with something fundamentally different as a carbon wrapped rotor. The only time it's happened is on motors that are just slight uprates with the same mechanical design.
Half the point was that the car would already be more expensive due to the other changes (wheels, body shape, interior, brakes, shocks) that they couldn't also throw in much more expensive motors and just rely on enough people buying a software unlock.
All this goes triple if the M3P requires a different battery to support the higher powers.
