The efficiency of the motor is just one small part of the overall system’s load upon the batteries. There are many other components and power costs. Tesla’s cost effective and power efficient thermal management is one example. HVAC is another. CoD, regen efficiency ... There are many more, and a lot of ways to lose 1% here and a % there to wind up with 45% less overall. Tesla has a 10+ year head start in finding those little cuts and figuring a cost acceptable resolution. This engineering is extremely difficult and Tesla is state of the art.

On the one hand, it means Tesla doesn’t have some magical technology lead that no one else can replicate. On the other, years of experience and refinement .... takes years to develop. Porsche has some work to do. 5 years behind Tesla appears to still put them 2 years ahead of everyone else ...

 

Oh, I have my ideas where several of Porsches problems are. I've shared a couple on these threads and gotten flamed as a result. So... we'll see.

Induction motors have been around since the 1890s, if not before. Nichola Tesla himself invented variations of them. But they were thought of as fixed speed AC motors and so really hadn't been used in EVs until the EV-1 in the 1990s. Though GM was playing with driving them with variable frequency/high power inverters as far back as in the 1960s (e.g. the Electrovair II prototype). They have advantages and disadvantages compared to DC brushless motors with magnets in them. Up until the Model 3, Tesla exclusively used induction motors. Now they use a PMSRM on one axle, and in dual motor cars, induction on the other. The PMSRM motor is a reluctance motor with some PM added to smoothen it out. (Sorry acoste but it is yet another variation from what is in the i3.)

 

Yeah, I was specifically replying to a post suggesting that motor inefficiency is the main cause of the Taycan's embarrassingly low range. I agree that it's probably a combination of a few handful of few % effects, plus the lower battery capacity and larger top/bottom buffers. I am perplexed that Porsche appears to have been surprised by the outcome - it just seems difficult to imagine that doing well on the standardized tests wasn't part of the development goals.

 

All of this has me thinking that Porsche should have stuck with what they are good add. Building a two seater sports car. Their first EV should have been the electric Boxster/Cayman. No one would have cared about range and efficiency. They probably could have made it less luxurious and lighter weight, using a smaller battery pack and therefore offered it for a lower cost as well. This would have been a better introduction and allowed them to work out the efficiency stuff over time. The Taycan crosses too much into the everyday driver market and this is where the range will really hurt it. Combine that with the ****ty charging infrastructure structure (read the article about charging issues with the E-tron) and they are setting themselves up for a lot of pissed off customers.

 

i think you need to look into Tesla’s acquisitions and their battery tech. They are much further ahead than 5 yrs ahead.

 

I disagree. That's too radical. Look at the furor on here about an electric 4 door, something not core to the Porsche brand. There are a lot of take it or leave it scenarios that can have people leave it if desired. Also, it's high price and somewhat low volume for Porsche. So they can afford to charge the customer for a little R&D cost, learn from "the fleet" data, and then step it up when they go to build the Macan EV. Because let's face it, that's their best seller by volume. They can't afford to boot that in any way. And then when the 718's get replaced by EV's, well, they had better have no excuses when they make an electric SPORTS CAR.

So while I do agree with some of your points, I think that those cars are too important to be the guinea pigs. Think about it, if they flub the electric 718, their entire idea of electric sports cars takes a huge hit. The idea of an electric Porsche in general takes a huge hit. The Taycan is super fast and comfortable and handles well. Porsche is likely embarrassed at the range and won't sell as many as they could have if it was better, but they will still get sales, and they will still learn how to make the next generation of EV's better. But without harming their core brand. And without losing money, since they are charging so much.

I think this path makes the most sense.

 

Agree - which is why it made sense to lead with the Taycan before releasing an EV Macan.

 

I kind of wish VAG would just buy Tesla - that would solve Tesla's manufacturing problems and VAGs range challenges.

 

i3 and Bolt is the same, permanent magnet assisted synchronous reluctance motor. As BMW says it "a proprietary hybrid synchronous motor designed to exploit both permanent magnets and the reluctance effect". https://www.greencarcongress.com/201...-20130812.html
Having said that BMW is moving back to AC induction motors from 2021 in order to avoid using rare earth materials.

There isn't much room for improvement left here.

 

Tesla says:

All Model S and X vehicles now benefit from Tesla’s latest generation of drive unit technology, which combines an optimized permanent magnet synchronous reluctance motor, silicon carbide power electronics, and improved lubrication, cooling, bearings, and gear designs to achieve greater than 93% efficiency.

https://www.tesla.com/blog/longest-r...s-even-farther

It is not clear to me what is included in the 93%. My understanding is that this is the whole drive unit's efficiency. Is the battery included? Probably not. (Round trip efficiency of the Model 3's battery is 95.5%) Transmission is possibly included, those are usually in the 99% range.

Now here is the BMW i3 that doesn't have the better SiC inverters yet unlike the Model 3 (GaN inverters are the best but I don't know anyone using them).

Notice that the Bolt motor is tuned in a way that efficiency drops with increasing torque while the i3's efficiency increases. BMW motor does not favor the EPA test cycle which contains light acceleration only.

 

Porsche has two optics problems

A $35k Tesla with 30% dead cells has more range than Taycan

a Model X towing a Taycan on a dolly has more range than a Taycan

The 4S with 225/275 tires is going to fare much better in EPA range

 

As any long-time EV owner knows when you account for the need to only charge the batteries up to 80% when using the car daily and not to damage or shorten the charging cycle of the batteries even the 4S will probably only do 129 miles on 80% power as a daily driver.... I will be canceling my order and going back to the MS

 

Since you are cancelling your order, are you losing your entire deposit? Or have you not actually placed an order and only have a refundable reservation slot? Either way, we will miss you greatly.

All long time EV owners also know that different vendors have different provisioning strategies to mitigate the impact of charging all the way up to (GASP!) 82 or 84 or even, heaven forbid 89%. There is nothing magical about 80% unless a company is really aggressively promoting range and has a small amount of under provisioning.

By the way, 80% of 200, is 160. So if you need an extra 31 miles on top of that, you are probably too conservative to drive a Porsche.

 

The 80% rule applies to cars with no top buffer. Both Audi and Porsche have top buffers, so daily charging to 100% is not a concern.

 

yeah I plan to charge to 100% each day - I'm also hopeful for a 5% "range boost" once porsche fleet data shows the battery management is too conservative