Posted on 12/18/2019 11:09:28 PM PST by dalight
The article is comparing to current lithium ion batteries, not gasoline-powered devices. You may as well complain that it doesn’t provide as much energy as a nuclear reactor.
You have accidentally hit one of the big targets for this tech. Electric cars will be seen as a key market for the core claim of this tech. Current Lithium Ion tech means that an electric car is a death trap in an accident.
Grandtour - Season 2 - Episode 1 - Aired: Dec. 7, 2017 - Rimac Concept One - Crashes, burns for days. Funny as all heck. But, you have to watch the whole episode to understand why. Amazon Prime exclusive series. Richard Hammond had been torturing his buddies with “health food only resort.” so if you start the clip from the beginning, they are rejoicing having “real” food.
https://youtu.be/k6Hf0WGquNM?t=445
Uh.. no. Same energy density as Lithium Ion batteries.
You are on the money, 5 minutes to 80% makes it possible to actually pitstop an electric car. This would be huge.
The problem with all electric cars is that efficiency of the car is largely illusory. Power Plants are enormously efficient conversion mechanisms for heat into electic power, but lots of energy is lost along the path of getting it into the car vs. just burning the fuel and using it to crank the tires via heat expansion. And, the other little problem is that the Dems have been shutting down virtually ALL power plant construction since the 1980’s. This has left the vast majority of power plants in service more than 50 years old. The design lives of these plants were 30 years.. and no one sees a problem. This is largely due to the efficiency of Gas Turbine technology and fracking. But, would the Electrical Grid actually take an increase of 10% or 20% to really offer energy for a similar percentage of electric vehicles? Nah.
Unless there is battery technology that they are withholding, they can only fit so many electrons in batteries.
It still is an issue, even with batteries.
Thanks! Good to know. And Slick.. :) IS there anything fracking can’t do?
See the link here .. http://www.freerepublic.com/focus/chat/3801997/posts?page=62#62
Watch battery based supercar do the same..
What battery tech do you suppose resides in a Tesla battery pack?
https://en.m.wikipedia.org/wiki/Tesla,_Inc.#Batteries
These are good observations. The Tesla Battery comes in 65 kWh and 85 kWh. Lets assume that we are talking about the 65 kWh battery (which makes things look worse from the heat dissipation side)
According to your numbers, 150kW delivered for 40 mins = 100kWh so 35kWh of energy must be dissipated during charging.. Ouch! if this is an 85kWh battery than its only 15kWh which you can start to imagine in terms of 10+ Hair Driers, not so bad, but significant.
This is the part where they partially address this...
It has an energy efficiency (defined by IBM as “the ratio of the energy to discharge the battery over the energy to charge the battery”) of over 90%.
This means heat loss on both charging and discharging is combined to less than 10% Lets assume 5% each way. This would be one third of the heat loss required for the Tesla if this is an 85kWh model’s charge time, or one seventh of the loss for the 65kWh model if that is what these numbers represent.
So, we go back through the numbers. 480V is max available for most situations so this is going to be fixed, and frankly 480V is pretty dangerous regardless.
Still at 480V, if I haven’t screwed this up @ 95% efficiency you would need 1,625 Amps to push 68kWh into an 85kWh battery. (this is the 80% charge time) - It would require some sort of drive up Bus Bars that slide into notches under the car. A cable that would carry 600 Amps at 480V more than 2” in diameter. It would take 3 - 1x6 Copper bars to carry this current.. LOL.
Perhaps there is a patent here.. if one decided to pursue it.
Thank you. I was about to post that, but try to always check “replies” first...
My favorite real-life, personal example of folks who should leave most of that kind of thinking to the engineers:
“Why can’t we mount a small engine that runs a generator to power the electric car and charge the batteries?”
Seriously. This was a serious question - from a lawyer.
I was involved in a test of Firefly batteries once. It failed. No one I know was interested in doing a second test.
How big is an electron? How big is an atom? Lots and lots of electrons available.. certainly there is a limit.. its a calculation that involves Coulombs law and Avogadro constant and the specific density of the material proposed.
But, I am not interested in doing that at this moment.
480V is not dangerous it is used everyday in thousands of industrial warehouses as 3 phase 480V AC power I personally have plugged with my bare hands into a live 480V socket a 50kw motor its no more dangerous than plugging in a 120V appliance as long as common sense is used. This is besides the point the current supercharger standards all have dead plugs and terminals until a complex handshake and charge communication protocol has been negotiated between the vehicle and the charge station the user is never exposed to live current at the plug nor cable.
The current standardized Type 2 plug has 8mm DC pins and 6mm AC pins for THREE PHASE power at up to a standard of 600V and 160 amp on EACH OF THREE PHASES. 160x3x600 = 288000 watts or 280kw. The current model 3 Tesla can take up to 250kw level 3 supercharger rates as designed from the factory. 480V 3phase AC power is the backbone of light industrial power in the north American market it is available anywhere you have industrial AC power think every warehouse and light manufacturing plant or shopping mall. In Canada the standard is 600V. Put in realistic terms 480V 160amp 3 phase is 230kw of power and this is available nearly everywhere you have commercial power services.
The Type 2 standardized plug also accepts 250amps at up to a now standardized 1000V DC for a 250kw DC fast charge. Three phase moderate voltage AC charging is the future, google ChargeAll for what the future of EV architecture looks like. Steping up too 960V 3 phase is harder to come by but is used for heavy industry so the transformers are readily available. 960V at the same 160 amps in 3phase AC power is 460kw.
Given that most local power pole voltages are 15000 volt three phase AC the source of 960V 3 phase is already in the neighborhood. also given the standard allows a max 1000V DC over the type 2 plug architecture means 960V 3phase AC is an afterthought from a materials stand point.
As for heat dissipation battery packs are now all liquid cooled with the same ethylene glycol antifreeze that cools gasoline engines. Put into perspective a 180hp gasoline engine is dissipating 75% of its net output in heat 25% at most is output to the wheels sorry thats just thermal dynamics. This is a simple calculation a vehicle getting 30mpg is using 4133 btu per mile in chemical energy 124000btu/gal of E0 / 30 = 4133btu/mile there is 3412 btu in one kilowatt hour so that vehicle is using 1.21 kwh in raw chemical energy per mile traveled.
A Model 3 Tesla uses 230 watt hours to go the same distance this gives you an idea on how much actual energy it takes to move mass down the road as batteries are 90+ efficient as are electric drive trains. For simplicity 230/1211= .1899 or 18% gasoline efficiency vs electricity. Why go through this calculation? My ICE car avg 30mpg and weights less than a model 3 has comparable seating and trunk space so comparable frontal area and therefore aerodynamic drag,less mass moving down the road which by physics takes less energy to move less mass a given distance with similar aerodynamic drag.
The heat dissipation system in my ICE is capable of removing a net of 180hp worth of heat given that to get 180hp net you have to burn 720hp worth of heat energy again only 25% of gross makes it at best to the wheels. In a ICE motor half the heat goes out the exhaust system we will be generous and say 60% the rest is deposited into the oil and coolant systems. So 720hp gross chemical energy x .75 x .40 enters the coolant system at its max design point. Thats 216hp worth of heat into the coolant system 216hp x 745.7 watts to the hp = 161000 watts dissipation in the radiators.
Charging a 90% efficient round trip battery means 5 percent is lost to heat each way so 5 percent of 250kw charge rate is 250,000 watts x 0.05 = 12500 watts of heat not even a tenth of the heat dissipation of a typical electric fan cooled radiator under virtually every hood in America. This is why the Model 3 can charge at up to 250kw with a liquid cooled pack heat is a non sequitur.
Well that is bad news! LOL
I am not in favor of doing anything that will make liberals happy. I would prefer to keep them in a state of seething rage (this being the only time they are funny to watch).
Gas-powered ones, of course.
See the video in my previous post.
OMG.. 480V is the most dangerous voltage possible. And you are alive by the grace of God if you have played with it as you say. You can’t fix stupid.
That sure was a takedown.. folks pay no attention to this first paragraph. 480V is a killing voltage because of what it takes to destabilize the heart, 100 mA. Below this, you just get a good shock and above you are clamped and if they can get you loose and get you breathing, you probably are going to make it. But, 480V needs a defibrillator, or you are screwed.
However, beyond this crazy statement, yea 6mm for 600V could do 160 Amp. But you would need 2/0 AWG to get that for 480V (approx 9mm).
I have thought on this and 480V service just wouldn’t do for a “pit-stop” charging station for Electric cars. It would have to be at least 13kV. I was talking about a 5-minute charge cycle to make for a gas station like a pit-stop experience.
You say, “Put into perspective a 180hp gasoline engine is dissipating 75% of its net output in heat 25% at most is output to the wheels sorry that’s just thermal dynamics.” LOL.. a lecture on Thermo.. really? However, you are right about how much energy is delivered by the automobile IC engine, if not a bit optimistic. But you are way wrong about what the real thermodynamics are for the Electric car.
But, I like your numbers.. so we will run with them to a point.
You say a gas-powered car uses 4133 BTU per mile in chemical energy. Cool. Sounds good.
But to get 1kWh of electric power on the line at the Powerhouse, it takes approx. 10,000 BTU. I worked at one of the most efficient power plants in the United States and our heat rate was between 9,650 and 10,050 depending on the point in the Turbine overhaul cycle and anti-pollution loading based on the unit. So, 1.21kWh per mile racks up to be 12,100 BTU’s per mile vs. 4133 for the gas-powered clunker. You just don’t see it because that’s miles away. And, this is not allowing for any transmission losses.
Right now the US transmission system is about 94% efficient in delivering electric power from the power station to the end-user.
https://www.indexmundi.com/facts/united-states/indicator/EG.ELC.LOSS.ZS
So, instead of 12,100 BTU/mi for this electric car, we are now at 12,900 BTU/mi. This is roughly 3 times as much energy per mile than the gasoline car using your own numbers. Mmmmm. Now Hydroelectric or Nuclear power would have different numbers, but Hydro is limited in the US (Canada has lots) and Nuclear is still a few years up the road at least.
I really appreciate your effort and thought. But, don’t play with 480V, ever. Gloves, insulated shoes and make for darn sure the circuit is off, isolated and tagged.
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