To boost the range of pure electric vehicles (EVs), automakers need more onboard energy. To get more energy, they need bigger battery packs.
That's why manufacturers such as Tesla Motors and BYD Automobile are rolling out vehicles with massive EV battery packs. Tesla's Model S offers a choice of three packs -- 40kWh, 60kWh, and 85kWh. The smaller packs have approximately 5,000 cells in them, while the bigger packs incorporate 8,000 cells, and weigh up to 1,200 pounds. Similarly, BYD's highly anticipated e6 will use a 1,400lb, 71kWh battery.
Not all automakers are building such massive packs. Nissan's Leaf uses a 24kWh model, while the Chevy Volt employs a 16kWh battery, and the Toyota Prius PHV (a plug-in hybrid) incorporates a 5.2-kWh unit. We've collected photos of a wide range of EV battery packs, ranging from production to research devices.
Click on the photo below to scroll through our EV battery slideshow:
The electric DeLorean's battery bay houses the vehicle's electric motor and half of its battery pack. (Source: DeLorean Motor Co.)
For further reading:
For a close-up look at GM's Chevy Volt, go to the Drive for Innovation site and follow the cross-country journey of EE Life editorial director, Brian Fuller. In the trip sponsored by Avnet Express, Fuller is taking the fire-engine-red Volt to innovation hubs across America, interviewing engineers, entrepreneurs, innovators, and students as he blogs his way across the country.
Very interesting slide show, Chuck. I loved seeing the different range of designs and options each of these EV players is bringing to the table. What strikes me, though, is that instead of making the battery packs larger to accomodate more on-board energy, shouldn't the innovation muscle be directed towards figuring out how to pack more power in a smaller space? There needs to be a page taken from the semiconductor space.
Well said and put in engineer terms. That was what I was alluding to. These giant batteries (ones weighing upwards of 1,500 lb--that's almost a ton) have to degrade range performance in the end. For more on-board energy, they need denser, more powerful battery packs--not physically bigger ones.
WOW! So, y'all mean that when the CHEVY VOLT grows to the physical size of a 1959 CADILLAC SEDAN de VILLE BROUGHAM, we'll have enuf energy storage that we'll be able to go to the local grocery store & back w/ the A/C & radio turned on, on a single charge? I can't wait!!!!! In the mean time, I'll stick w/ my trusty, ALWAYS reliable, TOYOTA, which consistently gets 35 mpg, and I can park in my garage!!!!
Generally speaking, the big problem with large batteries is that they horribly inefficient on short trips or when they are depleted. If you are driving an 800-lb depleted battery around, you're carrying dead weight. Same with a short trip to the store: Even if the battery is fully charged, why would you need an 800-lb battery to get a cup of coffee from your local Starbuck's?
The winner of the $5M 2011 Automotive X-Prize, Edison2, is taking a different and more practical track for their EV. They have focused on minimizing weight and aerodynamic drag, so that the energy requirements are minimized.
While their X-Prize winning car used an ICE, they found that venture capital was only avilable for EV's. So...they have paired their groundbreaking efficiency technology with electric power. Their spec's blow away any other EV I've ever seen (in terms of efficiency). The small battery reduces weight and cost, yet performs as well as large batteries spliced into rather conventional cars (Volt, Leaf, etc.).
What is so refreshing about Oliver Kuttner and his team is that they are 100% honest and transparent about their results, their successes and even failures. I followed his team's progress during the X-Prize, and had many email conversations with him. In short, they are taking an excellent ENGINEERING APPROACH to solving the core problem, instead of a MARKETING one where spin is created using half-truths and lies (like most current EV companies today).
If any EV is to be commercially successful, I think it needs to follow a path similar to theirs.
I think the Mitsubishi MiEV comes closest on that score (weight-wise), among the current crop of EVs. However, it's not cheap. The Mitsubishi cars web site lists it as "starting" at $21.6K and that's AFTER tax rebates/incentives. So on the cost curve versus gas cars, I don't see how it's cost effective. Electric cars won't take off until the same thing happens for driver as it did for factory, residential, and business owners. Namely, when energy becomes too expense, and you can reap real savings by going green, then people do it in droves. It's "follow the money," as opposed to the tree-hugger effect, which is really just early adopters. Now that gas is hitting $4/gal again, we'll see interest, but mainly in hybrids, which are now essentially mainstream. Plug ins still have a long way to go (economically speaking and I guess range-wise too :)
The current EV's being built are not economy cars but advanced tech, statment cars so should be judged by comparing them to BMW's, Lotus, etc, not with a Honda Fit. In that class they are rather inexpensive.
Big auto doesn't want to build cheap ones because they make less and EV's last so long, cutting both replacement and ICE repair parts profits, a major money maker for them.
I agree with Charles a too big battery which I define as over 100 mile range as wasteful. But so is any 1 person in any 3k-4klb cars, EV or ICE.
90% of US trips can be done with an 80 mile range 2 seat EV! And safe, cost effective ones can be done in under 1,000 lbs if they can break from steel bodies/chassis and finally go composite.
I agree with the 'smaller, not bigger' approach but 90% of trip needs is a non-starter for most buyers.
A second more efficient car is practical to buy for a lot of consumers but the overhead of owning is not. If the Fed. government wanted to help (without these stupid subsidies) it would mandate that insurance companies and states not insure and license cars but drivers. I can't drive two (or more) cars any further than I can one.
While it would be nice to have a vehicle to match intermittent needs, could people justify multiple cars ? My 2009 Aspen Hybrid is excessive for my everyday use - 5.7 Hemi, 6,000 towing capacity, 8 passenger, all-wheel drive. Even my wife's Prius is excessive for her everyday use - 1.8 (Sterling cycle ?), 4 passenger. But neither of us could justify having something like the original Honda Insight for everyday - 2 passenger, high mileage - and then a third and fourth car for 'special' days. And there is always the what-if ; what if I take the 2-passenger but then need additional passenger or cargo capacity later the same day ? We both accept that our cars are not ideal, but we each are willing to accept the trade-offs of our hybrids.
Will we soon see the day when all-electrics must be based on a truck chassis to carry the weight? (Anybody remember the Briggs and Stratton company's electric attempt?) It seems we are fast approaching that point, if we haven't reached it already. This easy fix of "more is better" gives me an uneasy feeling, as it appears to have done with many of the posters here. Shows how far we have yet to go before the EV is ready for prime time with the vast majority of car owners.
Hey Jerry I hear some TRUE incite making it's way to this discussion group! I would agree with your comments as where we are in the state of the art, price, etc. I surely DON'T agree with those encouraging ANY standardization at the stage of the game, which I see as killing a competion that just got started!
So I ask everyone one following this channel:
What players have well focused designs NOT guided by marketing committes but, rather incitefull engineering leaders willing to advance the state of the art?
What players are ALSO rans?
What players are most capable of imaginative SCIENTIFIC energy break-thrus that history deams the making of a new world and closing of our current era. (YOU WILL HAVE TO GO OUTSINE THE CHANNEL FOR THIS ONE)
I agree. One of the biggest killers of electric technology wold be standardization at this stage although standardization of charging station technology would potentially be a big help.
Other blogs on Design News have mentioned the need for better batteries, etc. This is the challenge to today's designers. Current designs have to allow for big improvements in technology so they won't become orphans when that "super battery" comes down the road.
I agree with you, Alex. A USA Today poll last year showed that 57% of Americans claim they wouldn't buy an electric car, no matter the price of gas. But I have a hunch that if gas prices went up to $10 a gallon, those poll numbers would be completely different. If car owners were confronted with a $150 bill for re-filling their gas tanks, electric cars would start to look pretty good.
A small (10 - 20 HP) ICE w/ generator as a range extender/recharger makes SO much sense. It's light, allows use of smaller battery, would give unlimited range at in-town speeds, allow recharging while parked when trip is over 50% of battery range and totally eliminates 'range anxiety'.
BMW useded this in one of their recent prototypes. I thought it was brilliant.
It almost sounds like we're relearning how and why the internal combustion became dominant, doesn't it? It would be nice if you could just carry the amount of energy you need, and/or pick up more along the way in a quick and efficient manner. Gasoline is not going to carry us in the long term, and battery power (and everything else) brings challenges of its own.
45 years ago the Mallory Battery Company of Canada produced a highly specialized D size cell, the energy density of which at that time (1967) matched the lithium systems of today. It was a difficult cell to manufacture and was shelved because an alternative system provided a compromise solution for the application for which it was targeted.
An extrapolation of the technology today combining advances in chemistry; greater manufacturing sophistication and other advances made over the intervening years suggests that EV battery packs matching what exists today would be lighter, take up less volume and be about 53% less expensive.
I was talking to a vendor involved in circuit protection the other day, and I didn't realize what a global safety issue there is involving LiIon battery technology. From the spate of Chevy Volt fire stories a few months back, one could have been led to believe that GM was at fault. In reality, Lithium Ion is an inherently risky technology, insofar as fire hazard when cells rupture, overheat or overcharge.
Just to add the point that weight in an electric car is not as negative a factor compared to non-electrics, due to regenerative braking, in fact if the regenerative braking was 100% efficient (that is if all kinetic energy was recovered back into the battery when braking) there would almost be no penalty with the added weight, plus the added stabily if the batteries can be located low and toward the center of the car, and the fact that cars with higher mass are safer in collisions, with all other things held constant. In the real world with say 75% efficent energy recovery, adding 20% to the cars weight (in batteries) would increase energy comsumption in stop and go (or uphill and downhill) driving by 5% maximum. In constant speed driving the only decrease in efficiency may be due to slight increase in rolling resistance due to the added weight.
"and the fact that cars with higher mass are safer in collisions, with all other things held constant."
Untrue. The reason why heavier vehicles have been safer is not due to the weight of the vehicle but rather the reason for the weight. Many of the specifically heaver cars are SUVs which are often intended for off-road use requireing a stronger chassis/body structure. Many others are Pickups, which lots of people making the engineering comments seem to forget are frequently the bets selling vehicles in North America. The Ford F150 is often the highest selling vehicle of the year. Trucks are built stronger to handle load hauling and also often have better crash surviveability.
If you put a 400CI V-8 engine in a Toyota Yaris is will be heavier but not better in a crash. The same thing is true of an electric vehicle with a 3/4 ton "gas tank."
Unsubsidized EVs simply don't sell because they don't match up to gas cars, weather we want to admit it or not.
In running into fixed objects, I think you're right. Mass alone doesn't help. But in collisions with other vehicles, conservation of momentum favors the heavier vehicle, simply on the relative delta-velocities experienced by the two. If you end up in the middle of the crumple zone, it won't help you, but mass does have a beneficial effect independent of stuctural design. Extreme example: a one inch rock and a ping pong ball collide. Both objects may survive with minimal damage, but I'd rather my brain experience the accelerations of the rock than those of the ping pong ball.
Now about your other comment about why unsubsidized EV's don't sell? I agree with you there. Liquid transportation fuels provide energy density and 're-charging' convenience thus far unmatched by plug-only EV's.
EV's will really take off when they become "drive-by-wire" where they will get their energy (and driving instructions) from the wires buried in the road (similar in concept to the streetcar or subway trains). Then there won't be any extra weight and there will be unlimited power to draw from. People won't develop anxiety when they need to travel farther than 100 miles.
Until then, it looks like hybrids and ICE will dominate with EV's being just a small percentage. The only other thing which may save EV's will be to standardize the battery packs (dimensions and connectors) so "Filling Stations" can be built where the entire battery pack is swapped out. Imagine gasoline cars if every different brand had their own unique way for delivering gasoline into the tank. Remeber the switch from leaded gas to unleaded? Doubtful that barcoding would have succeeded if every product required different equipment for scanning at the checkout. Or if every different railroad line had their own specs for track design (width). In a more simplified world, VHS vs Beta and DVD's vs (Pioneer) Laser disks didn't break out until the players got together and agreed on standards. Of course they were helped along by the porno industry which became the unifying force.
Until there is similar unified force for battery packs among the different car companies (Porno for battery packs?), EV's will continue to be a niche player. However I could be wrong.
Pass me my "Romancing The Bone" DVD. Turn it up, here comes my favorite part.
When considering EV or any other technology to a) save energy and b) lower carbon emissions efficiency is a key factor. Comparing EV to ICEV is not quite an apples to apples comparison. But there are some factors to look at.
Let's consider gas pump nozzle to flywheel efficiency for ICEV and mains plug to flywheel for EV.
With today's sealed fuel systems evaporative loss of energy is nil. So what goes in the tank comes out the flywheel minus inefficiencies. If an ICE is 40% efficient then 60% of the energy put into the tank is lost. For an EV there is charging loss (110% put into the battery to get 100% charge) converter efficiency (80-90%) and motor efficiency (90%). So worst case you have 65% of what went into the EV via the plug coming out the flywheel. If you add the efficiency of a plugless charging solution you have 49% coming out the flywheel. And if the EV sits for any amount of time there is self-discharge.
But there is an efficiency to obtaining the electricity at the outlet to charge the EV in the first place. Depending on how the power is generated the efficiency from lump of coal or therm of natural gas to the outlet is going to be 28% to 56% so the overall efficiency from burning hydrocarbons to the flywheel is 14% to 36%.
Admittedly these are all back of the envelope calculations. But the EV doesn't look so good when looking at the whole system. And the EV pollutes even when not running because it's generator, the coal fired plant cannot just shut down at the flip of a switch.
In addition to these considerations EV use will lead to an increased demand for power generation which will lead to smart power systems and Broadband over Power Lines (BPL) which will lead to a new form of pollution of the RF spectrum.
With the current efficiencies of gasoline engines they are still the viable way to reduce greenhouse gases when compared to EVs.
Bigger batteries are necessary because a lot of the curb appeal to EVs (barring the Prius) is high performance with a clean conscience. Charging an 85kWh battery in a reasonable amount of time is no mean feat with today's technology meaning it will be an overnight affair with a purpose wired high amperage connection.
1. Gasoline gets to the gas station much the same way coal gets to the power plant or natural gas gets to the turbo generator. That is a wash which is why I didn't mention it.
2. Exactly. When a gasoline engine is parked it is not burning anything.
3. Exactly, just like the 1999-2006 Honda Insight or the Prius. The Insight went 600 miles on 9 gallons. I know, I had one. At today's prices that is $45 worth of gas versus 6*$15=$90 worth of electricity.
4. Exactly, as does the Insight or Prius.
When comparing the cost of gasoline, discount the additional use taxes or figure the feds will add use tax when they get "smart meters" on residences and charging stations. Indiana even proposed charging additional tax at registration on Hybrids because of lost revenue due to the efficiency of that technology. It was ironic that my yearly registration cost more than my yearly gasoline bill for the Insight.
In Chicago, NY or LA electrics are a nice way to circumvent paying fuel taxes for now, but that will change.
The biggest argument for electrics is that we are past the tipping point in petroleum production.
TOP I do believe you need to reevaluate your position. My point in PAST replysIS, WE DON'T EVEN NEED a HV distribution GRID system IF we use NEW GENERATION methodes and forget the Grid!
Your statement 3&4 is ONLY true at this TIME, for WHERE/& TO WHOM, YOU PAID the BILL. It may go up, OR it may go away!
ONE SHOULD REALIZETHIS IS A TEST AND DESIGN PERIOD BEING DONE ON YOUR MONEY !!! I am sure DN readers aplaud you as I do for your early adoption efforts which we should all support if we ever want to use the improved technology and have the fical means to do so.
As a footnote I have 25 years of test information to tell you what I am eluding to is not only possible but EXTREEMLY afordable. Some firms ARE working to bring this to market cautiously here AND internationally.
If you buy a second car (electric ) to save the planet, you are now going to pay twice as much insurance even though you don't drive any more miles than you did with one car. You also increase the burden from sales tax and whatever the BMV demands from you. That alone keeps you from saving any money without even factoring in the inital price of the car.
I hear the horror stories about burning coal to charge the EV batteries. Then I hear the sad lament about having solar panels with nowhere to store the generated electricity. If I had an electric car, I would sure have solar panels to charge the battery. Then I would have to worry about Sun tax. We already have rain tax in Indiana.
Back in the 1970s, I built an electric riding mower and an electric motorcycle. No regrets.
Well PETE you need to let yorself be heard! Write your CONGERESSMEN! Let them know you dont want to pay for SUN especially when you can turn the power it creates off so easy; and ask them to JUSTIFY your rain tax?
FACTS: well run nuecler Fissionplants ARE (today) the greenest and lowest KWH cost generation @ about 1.5 cents, coal @ 3.0 cents /KWH, natural gas @5.4 cents/KWH, and oil @ 6.1 cents /KWH. Other Nano based nuecler FUSION derivites are NOW IN THE WORKS all yeild a CLEAN (NO ATOMIC radiation hazzards or polution product) 1 KWH @ 0.1 cents! This and other methodology is under investigation presently for automotive use.
Sorry I didn't buy an EV to save the planet. I bought an EV because I wanted an electric car and to save money. After 8,000 miles on the LEAF I am saving $0.20/mile in gas cost ($4.07 gas 17mpg and $0.14 KWHr @ 3.5mi/KWHr) so after 9 months I have $1,600 offset cost. If the battery goes 80K miles that's $16,000 for a new battery, if 160K miles it's a free car!
As for insurance the cost for the LEAF is the lowest for the 4 vehicles I pay insurance for. What else can I say?
So what's so bad about electricity? It can be made from many energy sources including coal, natural gas, hydro, and wind but my preference is to use nuclear based electric generation to power the planet and if you insist, you can use petrol to generate electricity at higher cost.
Instead of recycling or disposing the used LEAF battery (20KWHr remaining capacity), it can be charged by PV panels to store the electricity. I don't understand your taxing situations. There are many ways to tax EVs and I'm sure there will be additional ones soon.
I'd like to save money. I get 24 MPG in my vans and run them to around 240,000 miles. I would have to have them for longer trips even if I owned an EV. The way I look at it, the $40,000 for an EV would buy a lot of gas. Factor in the extra insurance and plates and you could have bought even more gas. A hybrid would be better if it had the needed cargo room. I could get by with one vehicle. Sadly, 240,000 miles comes out to a lot of batteries. Even recharging it for free, It would be hard to come out money ahead. This is not to say that there won't be some fantistic discovery in the world of batteries down the road. Look how far LEDs have come from indicator lights to lighting warehouses. Or maybe it will be a super capacitor or solar panels to power the electrolisis that will harvest hydrogen from water so we will have hydrogen for fuel cells.
We don't understand our taxing situations in Indiana either. Where did wheel tax come from? As if the plates didn't cost enough already. And if you put up a tent for an event in Elkhart, you pay tent tax. From my lips to God's ears.
I'm not down on EVs, I've built two but not for long trips. Regards, Pete O.
What van / engine are you driving that gets 24 mpg ?
There is a hybrid option that might work for you: supposedly GM still makes the Tahoe and Escalade hybrid SUV's. My 2009 Chrysler Aspen was supposedly part of a joint venture with the Chevrolet Tahoe, Cadillac Escalade, and BMW X6. My Aspen has a 5.7 liter Hemi V8. I think the GM's have the 6.0 liter V8.
The problem is that these are more LUV than SUV = luxury utility vehicles, not really intended to be a truck or cargo van.
And as mentioned in other posts = Hybrids tend to be purchased by early adopters, as the hard calculations of ROI usually don't justify the premium price. Part of the premium price of early Prius' was the Nav / DVD / Sound system. My wife's 2010 Prius doesn't have 'all the toys'. which reduced the price to a palatable level.
My current van is 2005 Caravan with a 2.4 L 4 cyl. that gets 24 MPG around town. I just got rid of a 1998 Voyager with a 3.0 V-6 that got about 24.5 MPG around town and around 29 on the highway. I seem to remember our 1984 Voyager with a 5 speed stick and 4 cylinder engine getting 30 MPG in town. I have a 3/4 ton Chevy that gets 13 MPG so it's nice to be able to fit a bundle of conduit (10 foot) in the van. I only drive the truck 500 miles per year. I'm not for bells and whistles. I never had a car with working AC until I was 60.
My wife got an Outback that gets 24 MPG in town but it cost $10,000 more than the minivan. I can't drive anything but American out of respect for the boys still on the Arizona. The Suburus don't coast well. When I see a stop sign a half mile down the road, I take my foot off the gas and coast all the way there in the minivan. She can't do that in the Outback without putting it in neutral. That's too much trouble so she keeps her foot on the gas a while longer. Pete O.
o 52 mph - 2003 Prius with +90k miles (total approaching 150k)
o 52 mph - 2010 Prius with +26k miles
The trick is to maximize EV or coast in free-wheel operation until the engine reaches an efficient, thermodynamic temperature range. Then drive the Prius as you would any other car.
Traction batteries have their use but it is best applied to provide power until the engine reaches peak, thermodynamic efficiency . . . and then give the engine a break when it can't be efficient. Meet me at the gas pump if you have a different point of view. <grins>
At last, a company is showing some sense with incorporating their batteries. TESLA seems to be using the batteries to replace the floor structure so it is the battery weight minus the floor weight (picture 16). This location makes sense since it gives a low centre of gravity, it is in an area that is acceptable to be flat and simple, and is air cooled from below with the option of cooling through the structure. (see citroen 2CV chassis and lightweight body concept designed before WW2 and produced in 1948) It can also provides underfloor heating for the cooler countries. Now all the car needs is a light aluminium or composite body strong enough to resist a roll etc. Next step is the bulkheads to be made into batteries. Eventually body panels would be the batteries. Replace your old batteries and upgrade the car design, colour and possibly battery design at the same time. I thought this was common sense over a decade ago so it is good to see it beginning to become reality. May the technology evolve. Exciting - isn't it?
deux chevaux Appreciated your humor and mention of the fasinating Citroen 2CV chassis and lightweight body concept designed. Good NEW design is refreshing and should be rewarded as it was a short time ago when Tesla's JB Straubel received the Engineer of The Year Award.
The following is from the TESLA site bio on JB; thought you guys would like to read it.
"As Chief Technical Officer The story of JB's career started at a junkyard in Wisconsin, where, at the age of 14, he discovered a discarded electric golf cart and decided to rebuild it. Thus began a lifelong fascination with energy work and electric vehicles.
As a co-founder of Tesla, JB has overseen the technical and engineering design of the vehicles, focusing on the battery, motor, power electronics, and high-level software sub-systems. Additionally, he evaluates new technology, manages vehicle systems testing, and handles technical interface with key vendors.
Prior to Tesla, JB was the CTO and co-founder of the aerospace firm, Volacom, which designed a specialized high-altitude electric aircraft platform using a novel power plant. At Volacom, JB invented and patented a new long-endurance hybrid electric propulsion concept that was later licensed to Boeing. Before Volacom, JB worked at Rosen Motors as a propulsion engineer developing a new hybrid electric vehicle drivetrain based on a micro turbine and a high-speed flywheel. JB was also part of the early team at Pentadyne, where he designed and built a first-generation 150kW power inverter, motor-generatorcontrols, and magnetic bearing systems.
Armed with a bachelor's in energy systems engineering and an master's in energy engineering from Stanford University, JB left the cold winters of Wisconsin for good. He now lives in Menlo Park, Calif., where he continues to indulge his passion for electric transportation: he built an electric Porsche 944 that held a world EV racing record, a custom electric bicycle, and a pioneering hybrid trailer system. JB is also an accomplished pilot.
Hi Charles, I am not aware of anybody doing research on body panels as batteries. I was intrigued about the emerging battery powered cars over a decade ago and as a design engineer and want-to-be 'futurist' I tried to predict how the technology would evolve and design with it. From memory, I first predicted that batteries would become part of a chassis structure where their weight doubles as poor quality structure for efficiency and low centre of gravity. I have now seen this in picture 16. Next other non cosmetic areas like bulkheads would be utilised as batteries. Eventually as battery technology develops they could cosmetically be overmoulded into complicated body shapes. If battery life stays at about seven years then these modular panels can be replaced to a later design of body or battery. If the battery/chassis design remains then you could change your pick-up to a five seater for a growing family. These panels do not need to be batteries, more recent thinking from a few years ago would possibly have them as super capacitors with seperate smart electronic modules to discharge them in a useful way. The panels would be more easily suited to layer lay-ups in a capicator type construction. I consider capicitor technology as not being far away, today, from this application. Batteries or capicitors could possibly be self charging with an invisible solar panel coating. Obviously battery technology needs to progress in the correct path for this application. In an accident we cannot have battery acid that will dissolve occupants or an impacted pedestrian, or heavy metals that will long term poison them. We also cannot have people being shocked or electrocuted. The panels need to be light and structural too. The panels will likely be thicker so lightness is important whereas strength will be easier due to thickness. My wife worked in carbon fibre lay-ups for aircraft. This is a strong method of construction like plywood and is analogous to capacitor lay-ups. Carbon fibre is a potential conductor for the devices and could be possibly grown into a latice shape (in a body panel shape) using nano technology. This would give strength and excellent surface area to a liquid or gel electrolyte. This is a long blog so I will leave it here. Thanks Charles for your interest.
I have a hunch that someone must be doing research on this idea, deux chevaux. As you point out, there are many technical issues to consider, but there are definite advantages to the idea. The biggest of those is the interior space challenge. Batteries that weigh 450-900 pounds inevitably take up too much cabin space because of the high floor. I've gotta think someone's looking into this, although I would imagine it would probably be a very long time before we would see it in concept form.
How about the opposite type of application for that 71KWH battery? Put it in an electric dragster and use all of hthose KWHs in 5 seconds.
The interesting thying is that with the best shut-off-and-coast technology it should be easy to double the miles per gallon performance of a vehicle without getting in anybodies way. Two things are needed that we don't presently have on most cars: A sut off and select neutral switch, and a smooth engaging starter motor. Probably driving the alternator like a motor would handle the starter, but the shut off and coast controls will be a bit more of a challenge.
This is SOP on Toyota-style "full" hybrids. There are two motor/generators. The smaller one revs the ICE up to 1,000 RPM before starting it, which is what allows the ICE to shut of at stops or while coasting. There's no mechanical neutral, but if both motors are off, the ICE puts no load on the drivetrain. In fact, there's a special "B" mode on a Prius transmission to allow the ICE to drag as an "engine brake", since ordinarily, it does try to coast when conditions permit.
Once going down a steep mountain in North Carolina, I drove for over a half hour without the ICE coming on once, in the 35-45mph range, and wound up at the bottom will a full battery.
the clean energy of electric cars mostly originates from coal fired power plants, when the coal gasoline is economically cheaper than petroleum at about 35 dollard a barrel. The oligopoly of oil and a corrupt government prevent technology from making the most economocally justified decision to use coal refined gasoline to power our cars, bypassing the burning of coal which is indirectly responsible for thousands of deaths annually each year. Electric cars powered by coal fored power plants by far the dirtest source of aoutomotive power---however out of sight is out of mind,,,,,,rest peacefuly in your electric car with the delusion of clean energy, oh yes, one last thing, ask why the EPA, overpowered by the oligopoly of petroleum based gasoline, refuses to allow coal to gasoline refineries at the coal mines mouth, (domestic energy) further reducing the point when coal gas is superior to electric cars. How stupid can you be thinking a car powered by eletricity fdrom extremely toxic sources is clean energy, just because the advertisments advertise it as clean energy---the law of advertising, states that advertising is just an offeer top do business, and an advertisor can actually lie in his adds DUH, but its legal " let the buyer beware" don't fall for the electric car gimmick. or fall for it, and watch football, basket ball, golf, hocky, etc become a talk football player, while the government stuffs slavery down your eonomic system posing as free trade, and globalization which means the slavers get most of the income, and reduces you to a real fool, or not who gives a s--t abput your children and their children, or the nation for tht matter, just keep up on whos who in the talk football world and maybe you could become president, and claim criminals as your children, 17 year olds without an allowance but, permitted burgler toold, the path to an allowace, and if anyone bothers them then make a hoody race card as a new addition to the deck of affirmative action biggotry, ha ha ha
"the burning of coal which is indirectly responsible for thousands of deaths annually" - that's a low ball estimate and some are not so 'indirect'. So many people run off on this tangent - the problem is not the electrification of vehicles: the problem is dirty power generation and an industry that has been allowed to compete with exemptions to many environmental laws that othe industries must meet - even the auto industry. The current configuration of the US power industry is a choice not a necessity - there is always the opportunity to make other choices; there is even the opportunity to use coal much more efficiently and cleanly but then you have Republican fanboys that go entirely the other way proclaiming that the EPA and/or the environmental regulation should be scrapped. As it stands you have smog in Yosemite and Grand Canyon. Burning fossil fuels in motor vehicles is a very inefficient means of converting latent energy into motion: there are ways to improve on this but as you can see from comments by tucsonics and many others, it's all about what's cheapest and ignoring the fact that technology always rides an experience curve with the cost of a capability declining in proportion to cummulative sales - thank heaven for early adopters who choose value over cost. Dirty power is a choice made by every American: compare the reduction in emissions and improvements in fuel economy achieved by auto manufacturers as compared to the fossil fuel power sector over the last few decades - only one has made great advances; there is no excuse.
GeorgeG, I keep hearing that statistic about burning coal and I wonder about where it comes from because nobody except those who wish to attack seem to use it. So where are these poor folks dying and what is the actual mechanism of their demise? I realize that coal mining is a dangerous profession and in China much more so. Or is thgat statistic 9one of those numbers invented by somebody who claims to b able to predict reality based on a very small set of data? That would be my guess, based on the general hysteria that goes along with those folks.
Seriously this whole battery thing is so far off unless someone has a creditable unforeseen revelation up there auto-technical selves. Nuclear or atomic generators the size of a shoebox and an electric motor and your in business. The Power supply would be moved from vehicle to the next and may be passed on after the owner expires. After all the power supply would last several lifetimes anyway. Totally green. No pollution, no danger not anything. You couldn't make it into a bomb and it wouldn't over heat and it would be regulated. It would just work totally efficient. You could bring the PS into your home and run you home with it to some degree. I mean really this is not so farfetched as the car itself in the 1800s. Just get over it and do it.
don't forget the waste heat which is a huge component of global climate change and the possibility of of a rupture, the potential for the crazies to make a dirty bomb if the radioactive material becomes readily available
If you're proposing the "nuclear batteries" (RTGs, radioisotope thermal generators) used in spacecraft like Curiosity, I agree about the "can't be used to make a bomb" part only to a small extent... you can't make an A-Bomb or an H-Bomb. But a couple of these would make a dandy dirty bomb. The one on Curiosity uses Pu-238, which is the most effective material; Sr-90 is also an option, though with a lower power density (actually higher in pure form, but it's super reactive with water and oxygen, so it's always used in some compound form, like strontium flouride. And even better dirty bomb potential -- Sr-90 is a bone seeker, and the most dangerous component nuclear fallout.
These batteries are a pretty simple concept... the hot nuclear material is surrounded by thermocouples, which turn a temperature gradient into electricity. The problem is efficiency... thermocouples are always below 10% efficient, to date.
You'll see about 90% of the original power level from the cell after 10 years, about 50% after about 90 years (87.7 years, the half life of Pu-238). They don't last forever. The power density is about equivalent to Li-ion cells.. about 0.57kW per kg. The fact it's useful for a thermal battery is relatively rapid decay. Sr-90 has about 1/3 the half-life of Pu-238, though it's cheaper to make.
Of course, Pu-238 is also extremely rare. NASA bought a total of just over 16kg from Russia, but Russia has stopped making it. The DOE is gearing up to make 1.5kg per year in the USA. Without this, we stop exploring space much beyond Mars. And there is no way in the world you'd really want large amounts of Pu-238 rolling around on the highways. Take a small BEV like the Nissan Leaf, which is driven by an 80kW motor. So to back this motor, you'd need 140kg of Pu-238. Even if you decided that the thermal battery only needed to actually supply 1/4 peak power (perhaps draining it constantly into a conventional battery or some advanced supercapacitor), that's still 35kg or Pu-238 per vehicle. Again, this ain't Mr. Fusion. The spacecraft powered by these use a few hundred watts.. nothing like a car.
Based on the costs of making Pu-238, a 50W supply runs about $1,000,000, so your 90-year Nissan Leaf would cost $400,000,000 - $1,600,000,000 for the power supply, and it would take the USA 23 years just to make enough Pu-238 for one car. Strontium is an abundant element, but Sr-90 too is manmade; with a 28.8 year half-life, you don't find it in nature. It's a more plentiful byproduct of nuclear fission than Pu-238, but not dramatically so.
There are actually Tritium batteries available commercially... Tritium has a 12-something year half life. These run in to the thousands for a battery that put out power in the microwatt range, but again, for a really long time if you only need a few microwatts... you don't even want to go there in terms of cost for a BEV... even a cellphone battery would run $20 million on this technology. Today. These are actually "beta batteries"... they're capturing the electrons released due to beta decay, not using thermal means. M
But any old EV is likely to have enough power for your house. The average home in the USA has 100-200Amp service at 220Vac, which is only 22-44kW, and you're rarely if ever going to run your home at peak.
I'm always leery of brute force approaches. As the batteries get bigger, more % of the cost of the vehicle, it's a brute force solution. It will die of bloat, overweight if not disinterest as the hybrid, a more sensible approach, takes over. Even the hybrid is overpriced and overweight. You have to look at the cost of ownership, not just the mpg. If you drive 10k miles per year at $3.85/gal and 25 mpg, you pay $1540. The car may cost $10k less than the hybrid equivalent. So you have six years of gas keeping your 25 mpg car. It's a huge premium to pay for the hybrids. Will electrics and hybrids depreciate less? Maybe, but you had to pay up front for an overpriced vehicle to begin with. I see electrics with battery bloat as an exercise in futility. Will history prove me right? IMHO yes.
I completely agree with you, Tusconics. Big batteries get depleted, and then you're driving around with a 1,200-pound dead battery in the back, which wastes energy. The wild card in all this is the emergence of government mandates. Automakers are going through this exercise because they fear the imminent 54.5-mpg mandate, which is supposed to take effect in 2025. I can't provie it, but I think a lot of people in the auto industry are waiting to revisit the 54.5-mpg topic in 2018, and maybe ratchet it down a bit.
The point most people miss in the whole discussion -- a Toyota style hybrid simply lasts longer, and has a much lower cost of maintainence. The three-phase AC motors will outlive the life of the car. At least coming on 200,000 miles on my 2003 Prius, the traction battery shows every sign of doing likewise... and I'm also approaching twice the useful life of any other car I've owned. There's no transmission or conventional starter motor to wear out. The ICE is always run at optimal efficiency, far lower RPMs than in a conventional vehicle, so it lasts long. My first tuneup was at 120,000 miles.
I agree that full BEVs are a far tougher nut to crack well, given the lack of fast charging, widespread charging infrastructure, current battery power to weight ratios, and battery life when run full cycled (hybrids only use a 40-60% charge/discharge cycle, which keeps the batteries going indefinitely).
But progress has already been significant, and it's not such a bad thing that this is a generational transformation. After all, at current personal vehicle use rates, the electric power output of the USA would need to double for everyone to go BEV. And that's before you consider commerical and industrial vehicles.
The great thing about internal combustion engines is that one of the two reactants needed to create mechanical energy, namely oxygen, does not have to be stored in the vehicle - it's in the air. Battery power, on the other hand, requires that both reactants be stored. The result is the huge payload of batteries that must constantly be transported in the vehicle.
I think there should be some kind of metric that compares the incremental cost to build an EV, (in terms of oil/energyequivalents), to the savings in the cost of energy over it's life. I suspect that this would be a small and possibly even negative number for most EVs today and probably for many green energy projects. Note that as energy costs go up any savings do not increase significantly since the cost of making the vehicles and batteries will be higher also. Finally, a proportion of the cost savings today is really just the difference between the delivered cost/watt of coal generated electricity and the cost of a watt produced by a gasoline or diesel engine.
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