Tesla is fast

On 2022-04-17, Flyguy <soar2morrow@yahoo.com> wrote:
> On Saturday, April 16, 2022 at 12:59:46 PM UTC-7, Cydrome Leader wrote:
>> Ed Lee <edward....@gmail.com> wrote: 
>> > On Wednesday, April 13, 2022 at 2:52:18 PM UTC-7, lang...@fonz.dk wrote: 
>> >> onsdag den 13. april 2022 kl. 23.02.08 UTC+2 skrev Ed Lee:
>> >> > On Wednesday, April 13, 2022 at 12:52:45 PM UTC-7, RichD wrote: 
>> >> > > Today the electric cars are the quickest on the road.
>> >> > > The classic petrol muscle cars are vying for the silver medal. 
>> >> > >
>> >> > > Was it obvious to the designers, from day one, 
>> >> > > that this would be the case? Is it simply a power/weight calculation? 
>> >> > >
>> >> > > I'm congenitally leery of simple explanations -
>> >> > For one thing, it's easier to install and control multiple motors. For maximum performance, you can put one (or more) motor per wheel, which is hard to do with ICE.
>> >> And electric motors can usually handle quite a lot of extra power short term 
>> > 
>> > I am thinking in terms of trucking. Perhaps 18 motors for 18 wheelers. Smaller distributed motors might work better for heavy cargo.
>> 18 motors for an "18 wheeler" makes no sense at all. Look at the axle 
>> configuration for truck. It also makes no sense to try to add power to 
>> trailers where eight of the tires are.
>
> Lithium batteries don't perform well in the cold, which trucks have to deal with. At -20 C the capacity is about 75%; at -40 C it is less than half. So those Tesla semis operating during the wintertime could see their range reduced to under 150/250 miles (depending upon the version). Of course, they could insulate the batteries and use a part of their energy to heat themselves (which would also reduce range).

Avoiding those temperatures will not require any effort on the road
between Sydney and Melbourne. The technology may need tweaking for use
in other locations.

-- 
  Jasen.

On Sunday, April 17, 2022 at 5:24:10 AM UTC+10, RichD wrote:
> On April 13, Ed Lee wrote: 
> > > Today the electric cars are the quickest on the road.
> >> Was it obvious to the designers, from day one, 
> >> that this would be the case? Is it simply a power/weight calculation? 
> >
> > For one thing, it's easier to install and control multiple motors. For 
> > maximum performance, you can put one (or more) motor per wheel, 
> > which is hard to do with ICE.
> At the risk of asking a dumb question... how do they sync the 
> speeds of the various motors? Does the vehicle have a single 
> centralized servo controller, monitoring them all? 

Have you never heard of ABS braking?

https://en.wikipedia.org/wiki/Anti-lock_braking_system

The modern ones have a rotation rate sensor or each wheel, and that could provide the feedback to control the speed at which each wheel rotated. Of course when a car (or truck) is traveling around a curve the wheels on the inside of the curve have to rotate faster than the wheels on the outside (which is what differential joints cope with). Tizzying up the system with separate motors on each wheel means that you can cope with this inside the electronics.

> In which case, one might ask what's the failure mode,  if that controller goes on the fritz - 


There's just such a controller in every ABS. They don't seem to fail. If one of the sensors stopped working,  there may be a get yourself home carefully mode. but I never ran into it.

-- 
Bill Sloman, Sydney

On Sunday, April 17, 2022 at 10:55:09 AM UTC+10, Flyguy wrote:
> On Saturday, April 16, 2022 at 12:59:46 PM UTC-7, Cydrome Leader wrote: 
> > Ed Lee <edward....@gmail.com> wrote: 
> > > On Wednesday, April 13, 2022 at 2:52:18 PM UTC-7, lang...@fonz.dk wrote: 
> > >> onsdag den 13. april 2022 kl. 23.02.08 UTC+2 skrev Ed Lee: 
> > >> > On Wednesday, April 13, 2022 at 12:52:45 PM UTC-7, RichD wrote: 
> > >> > > Today the electric cars are the quickest on the road. 
> > >> > > The classic petrol muscle cars are vying for the silver medal. 
> > >> > > 
> > >> > > Was it obvious to the designers, from day one, 
> > >> > > that this would be the case? Is it simply a power/weight calculation? 
> > >> > > 
> > >> > > I'm congenitally leery of simple explanations - 
> > >> > For one thing, it's easier to install and control multiple motors. For maximum performance, you can put one (or more) motor per wheel, which is hard to do with ICE. 
> > >> And electric motors can usually handle quite a lot of extra power short term 
> > > 
> > > I am thinking in terms of trucking. Perhaps 18 motors for 18 wheelers. Smaller distributed motors might work better for heavy cargo. 
> > 18 motors for an "18 wheeler" makes no sense at all. Look at the axle 
> > configuration for truck. It also makes no sense to try to add power to 
> > trailers where eight of the tires are.
>
> Lithium batteries don't perform well in the cold, which trucks have to deal with. At -20 C the capacity is about 75%; at -40 C it is less than half. So those Tesla semis operating during the wintertime could see their range reduced to under 150/250 miles (depending upon the version). Of course, they could insulate the batteries and use a part of their energy to heat themselves (which would also reduce range).

The capacity you are talking about seems to be the capacity of the battery to deliver current, which does decline at low temperatures, rather than the energy stored in the battery  which is what determines range, and doesn't decline in lithium batteries.

As usual, you don't seem to know what you are talking about.

Once a battery is delivering power, it is also warming itself up. Think internal resistance. As soon as you have got the truck moving, the power available to keep it moving  will immediately increase. Using some of the power stored in the battery to warm it up might be necessary, if the truck needed lots of power to get moving at all, but that doesn't seem to be an actual problem.

Keeping the battery warm while you are recharging it does seem to be necessary, but it isn't going to use up much power or energy, and will have zero effect on range.

-- 
Bill Sloman, Sydney

On Saturday, April 16, 2022 at 8:31:00 PM UTC-7, Jasen Betts wrote:
> On 2022-04-17, Flyguy <soar2...@yahoo.com> wrote: 
> > On Saturday, April 16, 2022 at 12:59:46 PM UTC-7, Cydrome Leader wrote: 
> >> Ed Lee <edward....@gmail.com> wrote: 
> >> > On Wednesday, April 13, 2022 at 2:52:18 PM UTC-7, lang...@fonz.dk wrote: 
> >> >> onsdag den 13. april 2022 kl. 23.02.08 UTC+2 skrev Ed Lee: 
> >> >> > On Wednesday, April 13, 2022 at 12:52:45 PM UTC-7, RichD wrote: 
> >> >> > > Today the electric cars are the quickest on the road. 
> >> >> > > The classic petrol muscle cars are vying for the silver medal. 
> >> >> > > 
> >> >> > > Was it obvious to the designers, from day one, 
> >> >> > > that this would be the case? Is it simply a power/weight calculation? 
> >> >> > > 
> >> >> > > I'm congenitally leery of simple explanations - 
> >> >> > For one thing, it's easier to install and control multiple motors. For maximum performance, you can put one (or more) motor per wheel, which is hard to do with ICE. 
> >> >> And electric motors can usually handle quite a lot of extra power short term 
> >> > 
> >> > I am thinking in terms of trucking. Perhaps 18 motors for 18 wheelers. Smaller distributed motors might work better for heavy cargo. 
> >> 18 motors for an "18 wheeler" makes no sense at all. Look at the axle 
> >> configuration for truck. It also makes no sense to try to add power to 
> >> trailers where eight of the tires are. 
> > 
> > Lithium batteries don't perform well in the cold, which trucks have to deal with. At -20 C the capacity is about 75%; at -40 C it is less than half. So those Tesla semis operating during the wintertime could see their range reduced to under 150/250 miles (depending upon the version). Of course, they could insulate the batteries and use a part of their energy to heat themselves (which would also reduce range).
> Avoiding those temperatures will not require any effort on the road 
> between Sydney and Melbourne. The technology may need tweaking for use 
> in other locations. 
> 
> -- 
> Jasen.

Tell that to the Canadian part of Walmart, who has ordered 130 of them.

On Saturday, April 16, 2022 at 8:57:35 PM UTC-7, bill....@ieee.org wrote:
> On Sunday, April 17, 2022 at 10:55:09 AM UTC+10, Flyguy wrote: 
> > On Saturday, April 16, 2022 at 12:59:46 PM UTC-7, Cydrome Leader wrote: 
> > > Ed Lee <edward....@gmail.com> wrote: 
> > > > On Wednesday, April 13, 2022 at 2:52:18 PM UTC-7, lang...@fonz.dk wrote: 
> > > >> onsdag den 13. april 2022 kl. 23.02.08 UTC+2 skrev Ed Lee: 
> > > >> > On Wednesday, April 13, 2022 at 12:52:45 PM UTC-7, RichD wrote: 
> > > >> > > Today the electric cars are the quickest on the road. 
> > > >> > > The classic petrol muscle cars are vying for the silver medal. 
> > > >> > > 
> > > >> > > Was it obvious to the designers, from day one, 
> > > >> > > that this would be the case? Is it simply a power/weight calculation? 
> > > >> > > 
> > > >> > > I'm congenitally leery of simple explanations - 
> > > >> > For one thing, it's easier to install and control multiple motors. For maximum performance, you can put one (or more) motor per wheel, which is hard to do with ICE. 
> > > >> And electric motors can usually handle quite a lot of extra power short term 
> > > > 
> > > > I am thinking in terms of trucking. Perhaps 18 motors for 18 wheelers. Smaller distributed motors might work better for heavy cargo. 
> > > 18 motors for an "18 wheeler" makes no sense at all. Look at the axle 
> > > configuration for truck. It also makes no sense to try to add power to 
> > > trailers where eight of the tires are. 
> > 
> > Lithium batteries don't perform well in the cold, which trucks have to deal with. At -20 C the capacity is about 75%; at -40 C it is less than half. So those Tesla semis operating during the wintertime could see their range reduced to under 150/250 miles (depending upon the version). Of course, they could insulate the batteries and use a part of their energy to heat themselves (which would also reduce range).
> The capacity you are talking about seems to be the capacity of the battery to deliver current, which does decline at low temperatures, rather than the energy stored in the battery which is what determines range, and doesn't decline in lithium batteries. 
> 
> As usual, you don't seem to know what you are talking about. 
> 
> Once a battery is delivering power, it is also warming itself up. Think internal resistance. As soon as you have got the truck moving, the power available to keep it moving will immediately increase. Using some of the power stored in the battery to warm it up might be necessary, if the truck needed lots of power to get moving at all, but that doesn't seem to be an actual problem. 
> 
> Keeping the battery warm while you are recharging it does seem to be necessary, but it isn't going to use up much power or energy, and will have zero effect on range. 
> 
> -- 
> SNIPPERMAN, Sydney

No, YOU don't know what you are talking about. Lithium capacity AND current drop with temperature, SNIPPERMAN - LOOK IT UP! Using ANY energy of the battery for heating WILL effect range, idiot.

On Saturday, April 16, 2022 at 8:55:09 PM UTC-4, Flyguy wrote:
> On Saturday, April 16, 2022 at 12:59:46 PM UTC-7, Cydrome Leader wrote: 
> > Ed Lee <edward....@gmail.com> wrote: 
> > > On Wednesday, April 13, 2022 at 2:52:18 PM UTC-7, lang...@fonz.dk wrote: 
> > >> onsdag den 13. april 2022 kl. 23.02.08 UTC+2 skrev Ed Lee: 
> > >> > On Wednesday, April 13, 2022 at 12:52:45 PM UTC-7, RichD wrote: 
> > >> > > Today the electric cars are the quickest on the road. 
> > >> > > The classic petrol muscle cars are vying for the silver medal. 
> > >> > > 
> > >> > > Was it obvious to the designers, from day one, 
> > >> > > that this would be the case? Is it simply a power/weight calculation? 
> > >> > > 
> > >> > > I'm congenitally leery of simple explanations - 
> > >> > For one thing, it's easier to install and control multiple motors. For maximum performance, you can put one (or more) motor per wheel, which is hard to do with ICE. 
> > >> And electric motors can usually handle quite a lot of extra power short term 
> > > 
> > > I am thinking in terms of trucking. Perhaps 18 motors for 18 wheelers. Smaller distributed motors might work better for heavy cargo. 
> > 18 motors for an "18 wheeler" makes no sense at all. Look at the axle 
> > configuration for truck. It also makes no sense to try to add power to 
> > trailers where eight of the tires are.
> Lithium batteries don't perform well in the cold, which trucks have to deal with. At -20 C the capacity is about 75%; at -40 C it is less than half. So those Tesla semis operating during the wintertime could see their range reduced to under 150/250 miles (depending upon the version). Of course, they could insulate the batteries and use a part of their energy to heat themselves (which would also reduce range).

The fallacy here is that the battery temperature is what is important to the range, not the weather.  When charging a truck will keep the battery warm as a by product of the charging, just like an ICE provides waste heat to the passenger compartment for keeping the passengers warm.  This is also true when driving, the battery heats up from waste heat in the battery and motor.  

I don't know about other cars, but Teslas have a mode where they will schedule the charging to end at a time of choosing, for the start of a trip, ensuring the battery is up to temp.  No big deal. 

So unless the vehicle can't be charged immediately prior to use, this is not a problem. 

-- 

Rick C.

-+++ Get 1,000 miles of free Supercharging
-+++ Tesla referral code - https://ts.la/richard11209

On Saturday, April 16, 2022 at 11:57:35 PM UTC-4, bill....@ieee.org wrote:
> On Sunday, April 17, 2022 at 10:55:09 AM UTC+10, Flyguy wrote: 
> > On Saturday, April 16, 2022 at 12:59:46 PM UTC-7, Cydrome Leader wrote: 
> > > Ed Lee <edward....@gmail.com> wrote: 
> > > > On Wednesday, April 13, 2022 at 2:52:18 PM UTC-7, lang...@fonz.dk wrote: 
> > > >> onsdag den 13. april 2022 kl. 23.02.08 UTC+2 skrev Ed Lee: 
> > > >> > On Wednesday, April 13, 2022 at 12:52:45 PM UTC-7, RichD wrote: 
> > > >> > > Today the electric cars are the quickest on the road. 
> > > >> > > The classic petrol muscle cars are vying for the silver medal. 
> > > >> > > 
> > > >> > > Was it obvious to the designers, from day one, 
> > > >> > > that this would be the case? Is it simply a power/weight calculation? 
> > > >> > > 
> > > >> > > I'm congenitally leery of simple explanations - 
> > > >> > For one thing, it's easier to install and control multiple motors. For maximum performance, you can put one (or more) motor per wheel, which is hard to do with ICE. 
> > > >> And electric motors can usually handle quite a lot of extra power short term 
> > > > 
> > > > I am thinking in terms of trucking. Perhaps 18 motors for 18 wheelers. Smaller distributed motors might work better for heavy cargo. 
> > > 18 motors for an "18 wheeler" makes no sense at all. Look at the axle 
> > > configuration for truck. It also makes no sense to try to add power to 
> > > trailers where eight of the tires are. 
> > 
> > Lithium batteries don't perform well in the cold, which trucks have to deal with. At -20 C the capacity is about 75%; at -40 C it is less than half. So those Tesla semis operating during the wintertime could see their range reduced to under 150/250 miles (depending upon the version). Of course, they could insulate the batteries and use a part of their energy to heat themselves (which would also reduce range).
> The capacity you are talking about seems to be the capacity of the battery to deliver current, which does decline at low temperatures, rather than the energy stored in the battery which is what determines range, and doesn't decline in lithium batteries. 

Both the time&bull;current and the voltage is reduced reducing energy.  You should know this from physical chemistry.  That's where I learned it, also every battery discharge curve I've ever seen. 

https://www.scirp.org/journal/paperinformation.aspx?paperid=80512


> As usual, you don't seem to know what you are talking about. 
> 
> Once a battery is delivering power, it is also warming itself up. Think internal resistance. As soon as you have got the truck moving, the power available to keep it moving will immediately increase. Using some of the power stored in the battery to warm it up might be necessary, if the truck needed lots of power to get moving at all, but that doesn't seem to be an actual problem. 

The battery also self heats when being charged.  Tesla allows you to specify your trip starting time and will charge the battery so it is just done when you are ready to leave.  This should be easy to do for trucks as well. 


> Keeping the battery warm while you are recharging it does seem to be necessary, but it isn't going to use up much power or energy, and will have zero effect on range. 

It's also free since the battery will self heat. 

-- 

Rick C.

+--- Get 1,000 miles of free Supercharging
+--- Tesla referral code - https://ts.la/richard11209

On Saturday, 16 April 2022 at 12:24:10 UTC-7, RichD wrote:
...
> At the risk of asking a dumb question... how do they sync the 
> speeds of the various motors? Does the vehicle have a single 
> centralized servo controller, monitoring them all? 
> 
The main control parameter is torque not RPM. The RPM largely takes care of itself except when the ABS or the electronic stability control is active.

After all when going round a corner the outside wheels have to rotate faster than the inside ones and tire wear will also affect rotational speed.
...
kw

On Sunday, April 17, 2022 at 4:32:21 PM UTC+10, Flyguy wrote:
> On Saturday, April 16, 2022 at 8:57:35 PM UTC-7, bill....@ieee.org wrote: 
> > On Sunday, April 17, 2022 at 10:55:09 AM UTC+10, Flyguy wrote: 
> > > On Saturday, April 16, 2022 at 12:59:46 PM UTC-7, Cydrome Leader wrote: 
> > > > Ed Lee <edward....@gmail.com> wrote: 
> > > > > On Wednesday, April 13, 2022 at 2:52:18 PM UTC-7, lang...@fonz.dk wrote: 
> > > > >> onsdag den 13. april 2022 kl. 23.02.08 UTC+2 skrev Ed Lee: 
> > > > >> > On Wednesday, April 13, 2022 at 12:52:45 PM UTC-7, RichD wrote: 
> > > > >> > > Today the electric cars are the quickest on the road. 
> > > > >> > > The classic petrol muscle cars are vying for the silver medal. 
> > > > >> > > 
> > > > >> > > Was it obvious to the designers, from day one, 
> > > > >> > > that this would be the case? Is it simply a power/weight calculation? 
> > > > >> > > 
> > > > >> > > I'm congenitally leery of simple explanations - 
> > > > >> > For one thing, it's easier to install and control multiple motors. For maximum performance, you can put one (or more) motor per wheel, which is hard to do with ICE. 
> > > > >> And electric motors can usually handle quite a lot of extra power short term 
> > > > > 
> > > > > I am thinking in terms of trucking. Perhaps 18 motors for 18 wheelers. Smaller distributed motors might work better for heavy cargo. 
> > > > 18 motors for an "18 wheeler" makes no sense at all. Look at the axle 
> > > > configuration for truck. It also makes no sense to try to add power to 
> > > > trailers where eight of the tires are. 
> > > 
> > > Lithium batteries don't perform well in the cold, which trucks have to deal with. At -20 C the capacity is about 75%; at -40 C it is less than half. So those Tesla semis operating during the wintertime could see their range reduced to under 150/250 miles (depending upon the version). Of course, they could insulate the batteries and use a part of their energy to heat themselves (which would also reduce range). 
> > The capacity you are talking about seems to be the capacity of the battery to deliver current, which does decline at low temperatures, rather than the energy stored in the battery which is what determines range, and doesn't decline in lithium batteries. 
> > 
> > As usual, you don't seem to know what you are talking about. 
> > 
> > Once a battery is delivering power, it is also warming itself up. Think internal resistance. As soon as you have got the truck moving, the power available to keep it moving will immediately increase. Using some of the power stored in the battery to warm it up might be necessary, if the truck needed lots of power to get moving at all, but that doesn't seem to be an actual problem. 
> > 
> > Keeping the battery warm while you are recharging it does seem to be necessary, but it isn't going to use up much power or energy, and will have zero effect on range.  
> 
> No, YOU don't know what you are talking about. Lithium capacity AND current drop with temperature, Sloman - LOOK IT UP! 

As Rick C has also pointed out, this is known and has been measured. He seems to think that physical chemistry comes into this, and Gibbs free energy does depend on temperature, but not much.

https://www.scirp.org/journal/paperinformation.aspx?paperid=80512

The paper he cites blames it all on the battery impedance changes, which means that when the battery self heats in operation, the effect goes away

> Using ANY energy of the battery for heating WILL effect range, idiot.

But not much, You are a simple-minded idiot who can't do quantitative thinking, which does lead you to make moronic blanket claims, and to ignore what's actually going on.

-- 
Bill Sloman. Sydney

On Sunday, April 17, 2022 at 9:38:02 PM UTC-4, ke...@kjwdesigns.com wrote:
> On Saturday, 16 April 2022 at 17:55:09 UTC-7, Flyguy wrote: 
> ...
> > Lithium batteries don't perform well in the cold, which trucks have to deal with. At -20 C the capacity is about 75%; at -40 C it is less than half. So those Tesla semis operating during the wintertime could see their range reduced to under 150/250 miles (depending upon the version). Of course, they could insulate the batteries and use a part of their energy to heat themselves (which would also reduce range).
> All modern EVs can heat or cool the batteries as needed. So after a short period of driving they will be at optimum temperature so they can be at full performance. 

Not trying to be pedantic, but not *all* BEVs heat/cool the batteries.  I know this is an issue in the Nissan Leaf, but then you did say, "All modern EVs".  They neither heat nor cool and the cooling can be a real issue at times, like when fast charging.  I met someone who has one and he talked about several times when he was worried about the temperature, but continued to charge.  Some of his stories were pretty desperate, like Ed Lee, trying to reach the next level 2 charger.  What a crappy way to drive! 


> The batteries are insulated and can use waste heat both from the batteries themselves and the motors to keep within a reasonable temperature range so minimizing the battery power they need to use. They can also use wall power to condition the batteries to setting out. 

I don't think the batteries are insulated.  I know my Tesla is not.  The batteries have a lot of thermal mass, so driving will heat them up, but it's not a fast process.  Likewise, charging will heat them up too, but again, not real fast.  Home charging with a level 2 connection can warm them, but it will take some time for them to reach optimum temperature, which I think is around 90°F.  Even bringing them up from Freezing to a temp where the regen braking works fully takes a while. 


> Tesla's are very popular in Norway even in low temperatures. 

Yeah, I'm not sure how much to read into that.  Norway is not as cold as some places in the US and Canada unless you are in the far north end.  Most people live in the southern end. 

-- 

Rick C.

+--+ Get 1,000 miles of free Supercharging
+--+ Tesla referral code - https://ts.la/richard11209