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On today's TMC Podcast, we ask the question "What is the Tesla Cybercab?". Join us on YouTube live at 1PM and participate in the chat.
The Leaf batteries are probably the only commercial EV batteries I actually don't like, due to the lack of proper thermal management... most of the ones I've come across are heavily degraded, so I stopped even looking for or bothering with them. They can definitely have some life in something like a solar setup, but they're super hit or miss on quality. Definitely not a good choice for an EV, IMO.
Probably why someone wanted to dump 50 of them. Now they are just slowly degrading in a warehouse because they don't have built-in charge controllers.
Wait, wait, do you remember when EM said the Y would have FWD in a tweet? Those were suspiciously absent at the reveal.....
JRP3
Hyperactive Member
Thankfully. I'm not going to criticize Elon for learning not to make mistakes.
Wait, don't larger cells have a worse guts to surface ratio causing them to be less apt for high load applications?
I also wonder where the hot water goes. Will it be used for showering by someone? In the climate cult people love to obsess about the breathe of life that is CO2, but blatantly ignore the actual heat generated at the very same moment. Where does the heat go? No-one wants to know or talk about that. Rare to find a paper taking the heat itself into account in any sort of way.
I also wonder where the hot water goes. Will it be used for showering by someone? In the climate cult people love to obsess about the breathe of life that is CO2, but blatantly ignore the actual heat generated at the very same moment. Where does the heat go? No-one wants to know or talk about that. Rare to find a paper taking the heat itself into account in any sort of way.
We're seeing Model 3 taking a 3C charge, but not yet a 5.5C discharge. Are the cells as good at that as 18650s?
A 102.4kWh pack from 2170s, will that do as well with L loads? We've not seen it from Model 3 P as yet. Which doesn't mean these cells never will bring that, with smart fuses and the like.
And regarding affordable 300mi cars...
A 300mi battery for average motorist use is like getting yuor wife a hummer to go her daily groceries with so she doesn't have to take the bicycle anymore. Utterly wasteful and polluting. Batteries are not Elon's farts, they take a lot of processing and energy. It's not all green butterfly holograms.
A 102.4kWh pack from 2170s, will that do as well with L loads? We've not seen it from Model 3 P as yet. Which doesn't mean these cells never will bring that, with smart fuses and the like.
And regarding affordable 300mi cars...
A 300mi battery for average motorist use is like getting yuor wife a hummer to go her daily groceries with so she doesn't have to take the bicycle anymore. Utterly wasteful and polluting. Batteries are not Elon's farts, they take a lot of processing and energy. It's not all green butterfly holograms.
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Excellent work. We cannot start recycling batteries soon enough. If Tesla doesn't play nice offering replacing batteries at a competitive cost, they have this coming. And a car that can suffice on less batteries that it's got, is being wasteful.
One Tesla pack's cells could power 3 cars pretty well. A Tesla wreck without battery can't be very expensive. If custom modules could be added modularly over time or to facilitate a particular road trip, that'd be a win.
Well, one of my ongoing projects is being able to replace a Tesla battery pack with a non-Tesla battery pack.
Right now, I've been driving a Model S almost daily that has no Tesla battery pack (empty pack casing with a dummy coolant loop), that believes it has a Tesla battery pack, but instead is running off of one Chevy Volt battery secured in the trunk. I've completely reverse engineered the Tesla BMS, protocols, etc, and have the car convinced that it has a 15 kWh battery pack with ~50 miles of range... and it works pretty well so far. Onboard chargers work, and technically could make supercharging work if the pack were large enough. This is mostly a proof of concept.
In the end, I'll be able to make fully aftermarket Tesla battery packs with various targets (range or power or both), and they'll be just bolt-in replacements that any shop can do (no need to fiddle with firmware, the pack handles all of that).
Was trying to find a pic of a full charge, but don't have anything handy... and at the time this was taken, the BMS wasn't reporting energy usage to the counters that tally it for the UI yet, so 0 kWh used since last charge, lol.
I think Tesla could easily make a 2170 pack for the S/X in the same form factor, but they're not going to do it. I'll probably have to do it at some point... but first I need to make my 2100A discharge capable Model S battery.
Interesting Jason. I’m actually working on a battery swap too. I’m planning on taking Tesla S modules and putting them into my Tesla RAV4 EV. Idk if you've heard of me but I’m the guy who made the T-Rex. The range extending trailer. Ive been working on version 2 and that’s almost done. V2 Is a camper on top of a complete Tesla 85kwh pack.
I’ve begun testing and I’m pretty confident I’ll be able to install Model S modules under the RAV4 EV. The voltage range would be different because I’d be using a differently configured pack. I’m thinking I’m going to need a CAN spoofing box for that reason. We will see.
I don't know if you were joking or not, but there have been much written about the heat island effect cities create from waste heat. Though the total amount of heat humans create is tiny compared to the amount of heat from the sun that is trapped in the atmosphere and a fair bot of heat radiates back into space on a clear night.
Also the heat generated by EVs is a minuscule percentage of heat generated by cars. The EVs with radiators have very tiny radiators compared to ICE and the coolant loops on cars take much more stress than an EV's cooling system. When you aren't driving hard or supercharging the radiators can even be shut down on an EV.
The only ICE that can go more than a few miles without fluid in the radiator have oversized oil circulation systems that act as a secondary radiator. Most ICE will crack the engine block without a couple of miles without radiator fluid.
Oh and the reason Tesla settled on the 2170 form factor is because it's the best trade off between energy density and efficient cooling. When battery cells get bigger it gets harder to keep the center within a good temperature range and smaller has too much wasted space.
At least in the US Tesla wrecks tend to be very expensive. I don't know his last name, but there is a guy with a YouTube channel called Rich's Rebuilds who started posting here on this forum when he bought a flooded Model S and put it back on the road. Due ot the success of his videos and stories about the rebuild, the prices for wrecked Teslas have gone off the peg.
Tesla has said they will recycle batteries when the time comes. Ultimately it will be cheaper than using raw materials. However there aren't enough worn out Tesla batteries yet to make it worthwhile to do it on anything but a very small scale. The EVs with the worst record for longevity are Leaf batteries because they are so poorly cooled.
The issue is the commute. Replacing the ICE vehicle with a (relatively) emissions free vehicle is a must. But root cause is the excessive distances traveled. Not only is the long commute an environmental issue, it is a time waster, something that is finite for all of us.
Most of my employment has been local, so perhaps I'm fortunate and also able to walk / cycle to work is a tremendous benefit both environmentally and physically. I feel for those less fortunate that have to work two part time jobs and get kids to school and run a home.
My issue is that why haven't we seen secondary uses for batteries, rather than recycling? For example, if we have a use case scenario that need xx amount of kilowatts, we simply build a pack that meet that criteria with used batteries. The degradation will continue as normal, but perhaps we over-provision so that the effect is felt less or eliminated during the usage lifecycle.
JRP3
Hyperactive Member
Secondary use is exactly what has been happening with wrecked Tesla's. Other than that we don't have large volumes of used Tesla packs lying around to be recycled.
Nissan and Renault have their battery recycling initiatives.
I commented on the heat ICEVs produce, not the most rabid climate warner will address that. It's all about the CO2. Which is plant food. Heat just IS. And blocked by the greenhouse, if I have to go by climate warners.
Yes, seriously. Those V3 cables are thin and flexible. They will create a significant heat loss. Where does the water go? It an external cooling system powered to cool it, or is the heat lost in a radiator? Hot water just pumped into the sewer? Or is it hot enough to extract energy from? In my opinion, it's worth trying to use that heat for applications where heat would have to be sourced otherwise. All about climate change, huh? We can hold Tesla to high standards. The world needs us to hold everyone to high standards. Neighbor, you never leave the city, why do you have a long range EV? That's wasteful, you should have kept the gas car an just chip tune it, maybe experiment with HHO on demand, see what you can do there.
I mentioned this trade-off in cell because wk057 thought the larger cells would cool better due to that larger surface area which according to my info is inverse of reality. Double the diameter of a cell, double the surface area, quadruple the content and thus heat...
I commented on the heat ICEVs produce, not the most rabid climate warner will address that. It's all about the CO2. Which is plant food. Heat just IS. And blocked by the greenhouse, if I have to go by climate warners.
Yes, seriously. Those V3 cables are thin and flexible. They will create a significant heat loss. Where does the water go? It an external cooling system powered to cool it, or is the heat lost in a radiator? Hot water just pumped into the sewer? Or is it hot enough to extract energy from? In my opinion, it's worth trying to use that heat for applications where heat would have to be sourced otherwise. All about climate change, huh? We can hold Tesla to high standards. The world needs us to hold everyone to high standards. Neighbor, you never leave the city, why do you have a long range EV? That's wasteful, you should have kept the gas car an just chip tune it, maybe experiment with HHO on demand, see what you can do there.
I mentioned this trade-off in cell because wk057 thought the larger cells would cool better due to that larger surface area which according to my info is inverse of reality. Double the diameter of a cell, double the surface area, quadruple the content and thus heat...
There are some people building them into stationary storage systems.
The amount of heat energy put into the atmosphere now by cars is about 12.7 TW (12 X 10^12) a day. Assuming all the energy in the gasoline is turned into heat. Not all is turned into heat, but about 80-90% is in one way or another. Solar radiation hitting the Earth is 174 PW (174 X 10^15) a day. About 30% is reflected back by the atmosphere, but the rest is absorbed by the atmosphere and Earth itself. That would be 121 PW absorbed. At the worst case scenario (100% of all the gasoline burned in cars being converted to heat), that's 0.01% of the heat the Earth absorbs from the sun every day.
Human beings produce between 100 and 150W of heat an hour. That's 16.8 TW a day (at 100W of heat). More than cars produce now. There are quite a few more animals than humans in the world and the warm blooded ones are all producing heat. The cold blooded ones produce some heat too.
Electric vehicles are significantly more heat efficient than cars. Even a power hungry EV like a Model S is 4X more energy efficient than an economy ICE car and only a small fraction of it's energy is turned into heat. The heat from superchargers is likely going to be more than for the cars themselves, but the number of cars fast charging on a given day is a small fraction of the total fleet and that is unlikely to change ever.
But there are many, many stationary systems producing as much or more heat than superchargers. Every large building has one or more giant air conditioners unit on the roof, quite a few industrial processes involve heat, in the winter every occupied home has heat escaping through the walls (insulation just slow down heat loss, it still gets into the atmosphere), and in warmer climates home air conditioner units put off heat in the summer.
The amount of heat put into the atmosphere from cars now is so low compared to the sun that nobody is worrying about it. Worrying about the effect from switching to a transportation that produces significantly less heat is getting into OCD territory.
CO2 is plant food, but if Earth's atmosphere didn't trap heat we'd all be dead long before we had to worry about no food. Earth is a good place for life because of the atmosphere's ability to hold heat from the sun overnight (without holding too much). In places with no atmosphere like the Moon, it can be deadly hot in direct sunlight and deadly cold in shadows only inches away.
Now the amount of stresses each human puts on the system both directly or indirectly is pretty large. Humans need to eat, so we have a footprint for that. We need transport, shelter, heat when it's cold, etc. And all that impacts the environment. Even when there were 2 billion of us the Earth could decently manage the impact, but we're over 7 billion now and the Earth is creaking under the strain. I've felt for years the biggest problem is not the CO2 we're generating but the total size of the human population, CO2 is just one of the effects. The Earth would be better off if we got down to about 2 billion of us, but doing that in less than 1+ centuries goes down roads that only monsters would contemplate.
If the atmosphere wasn't venting heat, life would be impossible as well.
There are allegations of geo engineering that's supposedly helping revert global warming to actually do the opposite. Afternoon overcast generation from con trails (if you ever look up, you've seen it) to lock in solar heat over night. Whatever causes it for which reason, it really doesn't help if you decide to measure AIR temperature.
CO2 is seen in high temperature Earth, I'm not convinced the causation relationship has been sold to us in the correct direction. Obviously, we are consuming too much of everything. And we're herding too many animal for meat production. Forcing us to grow crops just for them, destroying edible calories as cattle turns it into heat and manure. Deforestation to grow these cattle feeding crops. Not just lost CO2 sequestration but also less oxygen production and less biomass.
The whole warming debate around CO2 is so beside the point considering the power and mood swings and proximity of our sun while there is significant crust and volcanic activity. Dinosaurs roamed The UK. It used to be great weather there for a long time. The ice reached all the way South to the Alps and beyond as well after than time. And we didn't start farming until most of that was melted. Climate changes. It just does.
Anyway, slightly on topic I am disappointed in Tesla that we now see more than halved Q on Q S/X sales and it'all because they lied and didn't keep them as technology leaders. Super inefficient rear motors, costly imported cells that seem to not like 250kW charging, thin cabling to match. A few long overdue changes could have kept S/X production capacity limited. Just keep the cars relevant. Not having competition is apparently not everything. If you do less well than we know you can, you're not getting a high grade. Just like the smart kid in school that didn't really try on a test.
If they can find it in their hearts to simply MAKE the 120kWh 210 pack already, at 3C that's 360kW charging right there. Or a nice long 300kW flat line at least. 50% more than Model 3PD will do just fine, no need for smarter fuses or anything costly. Heck, send it to dual M3 rear motors. Ideally the same thing once on the front. Those motors would not heat up any time soon.
Tesla has been holding out on us and consumer hit back by not ordering S and X. The "production limited" rhetoric had died now, that's significant and scary.
SucreTease
Teslarian
Physicist here: All of these rates are nonsensical. TW, PW, and W are already rates. To say a rate per hour or per day is meaningless (e.g. 60 mph per day is nonsensical).
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