The Electric Vehicle Thread

[MRG]

In the 1970's, several friends and I used to camp out at the track Thursday through Sunday when the Formula One U.S. Grand Prix was held there the first weekend in October every year. Crazy times back then. And always a great race.

In 1973 Woodstock II was held at the track. My cousin, a local and still a little out of sorts from his free tour of SE Asia, put his motorcycle down going back to home. He wasn't carrying ID cause he wasn't planning on needing to go to the hospital.

His wife finally found him at the hospital. When she gets there he's still unconscious and she's asking about pain meds since he had broken a leg. "No lady there's a lot of people on drugs town this weekend and we don't know what he's taken". She assured them he wasn't on anything.

https://www.udiscovermusic.com/stories/bigger-than-woodstock-remembering-summer-jam/

 

[aja8888]

In 1973 Woodstock II was held at the track. My cousin, a local and still a little out of sorts from his free tour of SE Asia, put his motorcycle down going back to home. He wasn't carrying ID cause he wasn't planning on needing to go to the hospital.

His wife finally found him at the hospital. When she gets there he's still unconscious and she's asking about pain meds since he had broken a leg. "No lady there's a lot of people on drugs town this weekend and we don't know what he's taken". She assured them he wasn't on anything.

https://www.udiscovermusic.com/stories/bigger-than-woodstock-remembering-summer-jam/

What a story!

We went to the G.P. for about 4 years in a row in the mid and late 1970's and drove caravan style from Connecticut. Camping out was a nut show also. I had a 1971 VW bus, a friend had a pop up camper and a third had an old Chevy van. We set up camp on top of a hill a good ways from the track and had a 24 hour campfire (we brought the firewood) and enough beer to float a battleship. I had my Bultaco motorcycle and a friend has his Ossa for the muddy roads. It's an absolute wonder we survived the festivities and didn't get arrested as the NY State patrol was there (HA! trying to control 150,000 nut cases scattered throughout the racing site).

We actually did see some of the race too.

 

[NW-Bound]

Because of this thread, I spent quite a bit of time looking at info on the Nurburgring track, and learned a few interesting things (no, I don't plan to go there ).

There are a few car rental agencies right outside the start of the track. You can rent cars from a pedestrian VW Golf (240 euros/2 laps) to a Porsche 991 (5025 euros/10 laps).

Of course, there's insurance. I don't think your regular auto insurance will cover the damage you cause. You will need to buy special insurance, and it costs 500 euros, with a deductible of 30,000 euros. You can reduce the deductible down to 15,000 with a premium of 1,000 euros. That covers the damage you may cause to the track. Not sure if it covers towing or liabilities to other cars. I have not found out what it costs to cover the rental cars.

One rental agency rented a BMW M4 to Robert Kubica, who was a Formula One driver. Kubica rented the car for 36 laps. After just 468 miles of hard driving by Kubica, the agency examined the car, and found that all 4 wheel bearings had to be replaced. The brake pads which were new had worn down by about 1/2. The rental agency put on new tires at the 20th lap. Now all 4 tires needed replacement. No other damage to the car or unusual wear/tear was found.

The rental agency said Kubica's unofficial best lap time on the M4 was about 7:24. The official time of the M4 was 7:28.

 

[aja8888]

Because of this thread, I spent quite a bit of time looking at info on the Nurburgring track, and learned a few interesting things (no, I don't plan to go there ).

There are a few car rental agencies right outside the start of the track. You can rent cars from a pedestrian VW Golf (240 euros/2 laps) to a Porsche 991 (5025 euros/10 laps).

Of course, there's insurance. I don't think your regular auto insurance will cover the damage you cause. You will need to buy special insurance, and it costs 500 euros, with a deductible of 30,000 euros. You can reduce the deductible down to 15,000 with a premium of 1,000 euros. That covers the damage you may cause to the track. Not sure if it covers towing or liabilities to other cars. I have not found out what it costs to cover the rental cars.

One rental agency rented a BMW M4 to Robert Kubica, who was a Formula One driver. Kubica rented the car for 36 laps. After just 468 miles of hard driving by Kubica, the agency examined the car, and found that all 4 wheel bearings had to be replaced. The brake pads which were new had worn down by about 1/2. The rental agency put on new tires at the 20th lap. Now all 4 tires needed replacement. No other damage to the car or unusual wear/tear was found.

The rental agency said Kubica's unofficial best lap time on the M4 was about 7:24. The official time of the M4 was 7:28.

Driving street cars on that track is crazy. 99% of them are not set up or designed to be driven like that.

 

[RetireeRobert]

Son just bought himself a brand new Hyundai Sonata Hybrid. Pretty slick machine. It's full of technology and has all the bells and whistles. Even has solar panels in the glass roof to help keep it charged up. And he doesn't need to stop at the gas station all that often.

 

[Car-Guy]

I know that people like looking at the top speeds of these cars and are in awe.... but... they have nothing on a drag car...


I know this is true for an older corvette.... probably still true today... drag cars no longer drive 1/4.


SOOO, if you give a Corvette a 5 mile run so it can reach top speed when it hits the start line.... and the drag car has to sit there waiting for the Corvette to arrive doing 200 mph when it reaches the start line... the drag car WILL WIN the 1/4 mile race...


Yes, the drag car can start from zero, get to over 300 mph and pass the Corvette all within the 1/4 mile.. and less than 4 secs...





3.58 secs @ 386 mph



Fastest 1/4 mile ever 3.58 secs @ 386 mph (621.61 km/h)Santa Pod dragstrip is the venue in which the current world drag racing record, a time of 3.58 seconds

Interesting scenario... (I guess) But the Corvette doesn't need to rebuild it's engine every time it makes a 1/8 or 1/4 mile run either, like a top fuel dragster does...

So change the scenario a little bit... Example, my last Vette (totally stock) would run the 1/8 in mid to low 8's... (I'm guessing since I only timed/recorded the 1/4 and that was in the mid 11's) True a top fuel dragster runs the 1/8 in the mid 3's (much quicker)... But try it 25 times in a row, back to back in about an hour or so, and see who wins...

 

[NW-Bound]

... True a top fuel dragster runs the 1/8 in the mid 3's (much quicker)... But try it 25 times in a row, back to back in about an hour or so, and see who wins...

Or try to take a dragster outside of the track.

By the same token, you do not take a Formula One to Moab.

 

[NW-Bound]

I read that the hybrid Porsche 919 EVO used lithium cells from A123. And A123 is a well-known manufacturer of LFP or LiFePO4 (lithium iron phosphate) cells. It has been making LFP cells for many industrial uses.

The advantage of LFP chemistry is that the cell has a longer life than the other chemistries, and a life cycle of 2000 is common. It can also stand a full charge/discharge much better than the other chemistries, and a 100% discharge is tolerated, without severely impacting the cell life.

The main disadvantage of LFP is lower energy density, both volumetric and weight-wise. Hence, LFP has not been popular for consumer electronics, where the smaller size/lower weight/long run time of the other types are more important factors. LFP is also not common in EVs, due to the weight and range considerations. However, LFP cells dominate in energy storage applications, where size/weight is of a minor concern, and a long life is highly desirable. LFP chemistry also does not use expensive cobalt and nickel, just cheap iron.

It was the CEO of CATL, a Chinese LFP cell maker, who coined the term "million-mile battery", meaning the cells can be charged/discharged many cycles to last a million miles in a vehicle. Of course, the rest of the car falls apart before that, but that was the point he was making.

Tesla decided to start using LFP cells made by the Chinese, starting with cars built in its China factory. Musk has been raving about LFP cells. I have not been able to find out about the specs of these cars, to see how the use of LFP cells impacts the weight and range of Tesla cars made in China. I wonder if technology has helped in this area.

For energy storage, LFP is the chemistry to use. And the world including the US wants to go green, but China dominates in LFP manufacturing. It's a shame that no US industrial companies step up to the task. This technology is not rocket science, yet is a lot more important to our daily life than pie-in-the-sky space toys.

 

[NW-Bound]

Here's a video showing how powerful these A123 LFP cells are. This guy is doing something I would not do, by using 4 cells in series to start a car. Each cell is slightly larger than a C-size alkaline cell. I have some cells myself.

LPF cells have a nominal voltage of 3.2V, instead of 3.6V like the other lithium cells. Hence, 4 cells in series give you just the right voltage to replace a 12V lead-acid battery.

This guy is really abusing the cells which are rated at 120A max for 10 sec. I would not do what he did. However, the cells did not blow up.

PS. You can skip to 5:30 to see the real test. At 5:40, this guy did a very unwise thing, when he touched the two clips to show they were live. On more powerful packs, this would result in molten metal thrown in his face. He will learn that one of these days.

 

[Texas Proud]

Different competition...

A drag car does not have to take any turn. Race cars do.

And if acceleration is what it is all about, then a drag car has nothing on a rocket sled.

The world record for a rocket sled is Mach 8.5 (6416 mph). It is not revealed how many Gs it achieved, acceleration and deceleration too.

PS. The above supersonic rocket sled was obviously unmanned. Manned rocket sleds could not be that fast, without killing the test subjects.

The difference is that my comparison is that both are cars and both have ICE engine...


Yes, the cars are designed for different kinds of racing, but still a car... also both can be driven... a sled is just a fast item with no input from a driver...

 

[yakers]

PS. You can skip to 5:30 to see the real test. At 5:40, this guy did a very unwise thing, when he touched the two clips to show they were live. On more powerful packs, this would result in molten metal thrown in his face. He will learn that one of these days.

Sorta like welding

hey, maybe he can do field repairs

 

[NW-Bound]

Another advantage of LFP chemistry is its tolerance of abuses. Because they are safer than other types of lithium-ion batteries, some LFP batteries have been used in aviation applications.

The following video, which is representative of many posted by LFP makers, shows how an LFP cell and another lithium cell react to getting punctured.

Note that I would want to see the LFP cell being fully charged before getting punctured. A fully-charged battery reacts more strongly to abuses.

Here are some demos by Winston, an established LFP cell maker, where an LFP cell is punctured, severely overcharged, short-circuited, and set aflame with a torch. All these torturous abuses are big no-nos with other types of lithium cells.

PS. Here's another demo, where the lithium-ion cell was at 4.2V, and the LFP cell was shown at a voltage of more than 3.4V, meaning both were fully charged.

 

[oneill225]

Tesla Production About to Explode

For those interested, Tesla is on the verge of starting limited production at their Giga Austin and Giga Berlin factories. Full production will start early in 2022.

Good news for a company that is selling the Model Y and 3 faster than they can build them (currently sold out for the rest of 2021).

This is the Texas factory:

This is the Berlin factory:

 

[ERD50]

Here's a video showing how powerful these A123 LFP cells are. This guy is doing something I would not do, by using 4 cells in series to start a car. Each cell is slightly larger than a C-size alkaline cell. I have some cells myself.

LPF cells have a nominal voltage of 3.2V, instead of 3.6V like the other lithium cells. Hence, 4 cells in series give you just the right voltage to replace a 12V lead-acid battery.

This guy is really abusing the cells which are rated at 120A max for 10 sec. I would not do what he did. However, the cells did not blow up. ...

Interesting. The battery for our Honda CR-V is rated ~ 425 CCA, so 4 of those 120A cells in parallel would exceed that spec (with 4 in series to reach 12V, so 16 cells).

The CCA spec is for 30 seconds though, but in real life, a 10 second engine crank is a long time. Considering most times an engine starts in a second or two, with far less than the CCA rating, seems that 16 cells could be reliable?

Extrapolating a bit, the 6 mOhm spec, and 4 cells at 13.2 V dropping to 10.2 V at start would imply that a cell couldn't provide much more than that 120A anyhow - a 3 V drop and 4 * 6 mOhm = 125 Amps. I don't really trust his meter to give a peak reading, I think you'd need a scope across a length of the battery cable (calculate resistance) to do that.

At ~ $6 per, that's $96, cheaper than a lead-acid. But you'd need some kind of charge controller, and maybe a heater to charge below freezing (though starting the car would probably heat the battery a bit, then heat from alternator power, so maybe not a big deal)? A BMS could just shut off the low current stuff, which would prevent the starter from kicking in with no power to the ignition switch - so no need for a 500A switch.

-ERD50

 

[Koolau]

Interesting. The battery for our Honda CR-V is rated ~ 425 CCA, so 4 of those 120A cells in parallel would exceed that spec (with 4 in series to reach 12V, so 16 cells).

The CCA spec is for 30 seconds though, but in real life, a 10 second engine crank is a long time. Considering most times an engine starts in a second or two, with far less than the CCA rating, seems that 16 cells could be reliable?

Extrapolating a bit, the 6 mOhm spec, and 4 cells at 13.2 V dropping to 10.2 V at start would imply that a cell couldn't provide much more than that 120A anyhow - a 3 V drop and 4 * 6 mOhm = 125 Amps. I don't really trust his meter to give a peak reading, I think you'd need a scope across a length of the battery cable (calculate resistance) to do that.

At ~ $6 per, that's $96, cheaper than a lead-acid. But you'd need some kind of charge controller, and maybe a heater to charge below freezing (though starting the car would probably heat the battery a bit, then heat from alternator power, so maybe not a big deal)? A BMS could just shut off the low current stuff, which would prevent the starter from kicking in with no power to the ignition switch - so no need for a 500A switch.

-ERD50

While beating the battery sellers at their own game sounds intriguing, I'm at that age and temperament where I just want to replace my battery and go - no worries about reinventing the car battery.

One thing I've been lucky with in the Islands is finding a place that offers used lead-acid batteries for $30, installed. They are guaranteed for 30 days. I believe I've purchased 5 over the years and only one died shortly past the 30 days. The rest gave good service for several years. I wouldn't do it on the mainland because my car sits so long my buddy has to detach the battery to prevent phantom drain in between monthly starts. So YMMV.

 

[ERD50]

While beating the battery sellers at their own game sounds intriguing, I'm at that age and temperament where I just want to replace my battery and go - no worries about reinventing the car battery. ...

Yes, I wouldn't actually do this (though a little tempted, just as an exercise), it's more along the lines of thinking that this might become mainstream as LiFePO cost come down. They are lighter than Lead-Acid, and car makers are looking to reduce weight wherever they can.

Looks like 76 grams per * 16 = 1216 grams, about 2.7 pounds, compared to ~ 27 pounds for lead-acid.

-ERD50

 

[NW-Bound]

With the LFP cells being so powerful, you would think every car maker would throw away the lead-acid battery in order to save weight.

Ah, not so fast!

LFP cells and other lithium cells would not last long under the hood of the car where it's that hot. Maybe a couple of days. And even if you put it inside the passenger compartment, you still have a problem in cold climate, where the interior of the car gets below freezing overnight.

You don't win!

 

[NW-Bound]

If it were not for the temperature problem, one could contemplate a potential use of these small LFP cells for emergency.

The capacity of each 26650 cell shown in the video is a mere 2,500 mAh. You can carry a small battery made of 8 cells in a 2P4S configuration for emergency use. If the battery charge happens to be low, you can charge it up with a small solar panel.

A small flexible PV of a couple of square feet and that can be rolled up like a mat will charge up the battery to a useable state in 1/2 hour or less. Such a small portable PV can put out 2A at 12V easily.

PS. For emergency engine starting by accumulating charge from a small solar panel, one can also use supercapacitors. A bank of them in series would be the same size as the LFP 26650 cells. Perhaps these supercapacitors have a larger temperature operating range, but I am not sure.

I just found out that there are capacitor jump starters on the market already. One just needs to add a small solar panel for backup charging.

 

[NW-Bound]

One thing I've been lucky with in the Islands is finding a place that offers used lead-acid batteries for $30, installed. They are guaranteed for 30 days. I believe I've purchased 5 over the years and only one died shortly past the 30 days. The rest gave good service for several years...

What is their source for these good used batteries? Are they thrown out after a certain time, just to ensure reliability, such as for rental cars?

 

[Koolau]

What is their source for these good used batteries? Are they thrown out after a certain time, just to ensure reliability, such as for rental cars?

Honestly, I keep thinking I'll ask them, but always forget. Wild guess is scrap yards.

 

[ERD50]

With the LFP cells being so powerful, you would think every car maker would throw away the lead-acid battery in order to save weight.

Ah, not so fast!

LFP cells and other lithium cells would not last long under the hood of the car where it's that hot. Maybe a couple of days. And even if you put it inside the passenger compartment, you still have a problem in cold climate, where the interior of the car gets below freezing overnight.

You don't win!

Can you expand on that temperature issue- the sources I looked at were all over the map and not clear regarding storage temps vs usage temps, and I know you are well informed on this with your solar/LiFePO4/AC set up.

-ERD50

 

[ERD50]

With the LFP cells being so powerful, you would think every car maker would throw away the lead-acid battery in order to save weight.

Ah, not so fast!

LFP cells and other lithium cells would not last long under the hood of the car where it's that hot. Maybe a couple of days. And even if you put it inside the passenger compartment, you still have a problem in cold climate, where the interior of the car gets below freezing overnight.

You don't win!

Also, I will take another look at this for my sump pump battery backup. It's a 12V AGM, installed in 2019, so maybe good for another 3 years (rated 75 AH)? By then, the price of LiFePO4 should be competitive (not sure what the BMS would cost)?

(checking price again....) Arghhh, for 75AH, still big $$$ - those $6 cells are just 2.5AH, so need 30 in parallel! Times 4 for the 12V is 120 cells, so $720! Though 75 AH is maybe overkill. The pump is ~ 15A, 5 hours continuous simple math (de-rate by quite a bit at that current though). But the pump should not need to run continuous, and a 10% duty cycle would provide over a day of back up. If I had that long of a black out, I would run my inverter from my car, power one of the other pumps, and charge the battery.

When the price drops in half, that could be worth it. The BMS would not need to handle the 20A fuse rating, only the charge current of 1.6A - the low voltage cut-off could just break the connection to the float, which is a low current sensor.

-ERD50

 

[ncbill]

You can buy premade LFP batteries (with BMS) already configured for 12VDC applications.

The UPS/alarm backup sized ones (12VDC, ~7ah) are now cheap enough for me to consider...larger sizes, e.g., 100Ah are still too $$$ for me, though.

 

[explanade]

I just tried to get some quotes for Rav4 Prime.

Local dealers want $3500 markup.

Even regular cars, the dealers are insisting because of chip shortage they will have their dealer mark up and will ignore terms on the manufacturers' websites.

 

[Sunset]

What is their source for these good used batteries? Are they thrown out after a certain time, just to ensure reliability, such as for rental cars?

My old chemistry professor told me , he used to take old batteries, open them up, clean out the crap at the bottom put them back together and refill with fresh acid.
The stuff that accumulates at the bottom will eventually touch and short out the plates.
He would then sell the batteries.