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Re: Is all Common Sense Lost?
Powa-Master   9/19/2011 11:14:56 AM
Now that we are al being a bit pompous... As a power systems engineer ffo 29 years, and having worked in motive power and industrial battery chargers I can tell you that in 1997 the coal BTU to torque efficiency bback then was rated at about 6%... Since then if you consider breakthru switched mode power systems you might edge that number up to 10%, which is still behind the best gasoline to torque x time efficiencies of up to 23%. If 36.4 Kwh of power gives you about 8 Kwh you can back-up and figure that it takes about 80 Kwh equivalent power from the grid to give you equivalent to a gallon of gas... However, of that power the utilities eat the 50% line loss, causing the consumer to pay for 40 Kwh x 0.12, or about a $4.80 per gallon equivalent BEFORE you even get to amortizing the cost of battery and technology. Ergo the public hesitation to by E-cars or" Coal powered" cars as I call them. Now if the tree-huggers are taking tabs on environmental impact in an honest manner, the 50% line losses contribute to so-called "man-made global warming et cetera". Neither the consumer nor mamma nature may be happier with Electric cars in the end... And I am not even covering the continous environmental impact of battery construction and maintenance. Tell me where I am wrong.

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Re: Is all Common Sense Lost?
nicart56   9/19/2011 11:14:01 AM
Please explain in detail to me the cheaper alternative. Thank You!

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Li+ Battery
rosek   9/19/2011 10:34:27 AM
Having worked on high performance hybrid drive systems for the last 10 years or so, it is clear that the battery is the biggest problem.  The batteries we use are the large, cylindrical, format types and are indeed, pricey (we would change out bad cells in lieu of replacing the whole pack).  For the consumer market, basic transporation vehicle, perhaps we've finally met the limit of cheap, low-hanging fruit in the energy market.  Maybe future drivers will just have to pay more for the privilege of driving an automobile?

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Is all Common Sense Lost?
Common.Sense.1st   9/19/2011 10:04:23 AM
As a Physicist / Engineer who specializes in alternative energy sources/resources...(not wind, solar, hydro,etc.)  I am sorry to say this but, "HELLO....KNOCK-KNOCK is anyone up there?"

Is there no common sense anymore?  Although the article is based on a financial premise, why is it that noone is really laying down the non-financial numbers that are the basis of the topic.

Gasoline offers approx 124,200 BTU per gallon; 124,200 BTU = approx. 36.4 KWh of energy; and  1 KWh of Grid averages 12 cents per KWh.

So do some math based on energy first and then apply the real cost to EV Batteries, or even fuel-cells to really get to the point. When America went through this same issue back in the 1980's this was studied to the "hilt" then..and it was calculated the Batteries that could supply around 700 KW/h were what was needed for electric cars to be viable (hey, did you notice the relationship between the approx. 700 and 36.4?). Has everyone forgotten everything already???  The bottom-line here is there are only two battery chemistries that can do the job or actually "OVER-DO" the job...and we are simply not using them eventhough there material costs at retail are between 1/10 and 1/4 the price of Lithium....   The reason being we are still in a "GREED" based society of putting "Band-aids" instead of "fixes", so we try to solve the problems with the least possible upfront expense, even when a little more could "fix" everything. Sad, but oh, so true....






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Re: Round and round
Walt   9/19/2011 9:49:19 AM
The questions that have been going though my mind from the beginning of the EV push were 1. How long will these battery chemistries continue to hold an acceptible charge level in real-world applications (all battery chemistries are affected by charge/discharge patterns)? and 2. What will the end user replacement cost be when they need to be replaced - including installation?

We don't complain too much when our notebook computer battery packs only give us 1 hour per charge after a year or two of use, but when our EV will only travel 10 miles on a charge after a few years and we have to spend $2K or $3K to replace them - every few years - that's going to hurt, and it would quickly sour me on owning an EV...


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Oh, one more thing...
Ratsky   9/19/2011 9:45:11 AM
... or two!  Most estimates of total battery SUBSYSTEM costs (what is really important) have to consider other items and factors.  One large cost is the cost of the external charging station. For the typical "slow" charger (overnight recharge for 100% capacity) this would be a 2KW+ unit, with a very sophisticated charge management system; it requires at least a dedicated GP branch circuit (20A @117V US, 10A@220V EU).  Any quicker charge requires a special wiring arrangement (as much as a 50A one for 2-3 hour recharge).  Oh, and unless one is dreaming or using mind-altering substances, the vehicle will be a fossil-fuel hybrid (or share a garage with a fossil-fuel vehicle in most cases), so the unit has to be at least spark-free (or fully explosive atmosphere compliant, which believe me ain't cheap!).  factoring the installation costs, etc. this alone could easily average $2,500 or more.  Of course, the total cycle efficiency (KWH drawn from the grid divided into the usable KWH output of the battery pack) of no better than 85-90% has to be considered in the "mileage" obtained.  I'm afraid far too many engineers these days weren't required to take a full semester of thermodynamics in school, so they don't really appreciate that EVERY step of energy conversion and control is LOSSY.  These are also typically the proponents of the "hydrogen economy," never recognizing that hydrogen is an energy DISTRIBUTION mechanism, NOT a FUEL.

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Re: Round and round
melllowfelllow   9/18/2011 2:15:31 AM
Congratulations Charles! Getting David Swan's input and observations presented what some of us see as a 'real world balance' to the pontifications of inward looking industry experts.

As I sit in front of my computer late at night and type my anonymous thoughts under the guise of a pseudonym, I concur with David Swan's comments. Engineers [and others] are notorious for taking the price of a BOM, or in the battery pack cell case - a subset of the BOM, and declaring that is what the subassembly should cost without any testing, qualifying, handling, labor, support/warranty, or manufacturing cost consideration. I do not see any significant problem with cell prices vs. pack prices.

We live in an age where a large percentage of folks know just enough to be dangerous in their quest for data and projections. Many of us have become spoiled during the last 20 years of technology advances. Although a great many new products have been 'hatched' during that time, we have been able to 'hang our hat' on some future projections [both technology-wise and cost-wise] for the new products by using a certain amount of historical extrapolation. If we go back to the time frame of the Intel 8008 [which ironically was designed under a contract to be the heart of a single board desktop computer], folks did not have the ability to project future microprocessor or memory costs [or future technical capabilities]. IMO, automotive electric power technology [batteries today] is at an equivalent stage of maturity in the vicinity of the 8080/8085/80186. We will need battery power/size/cost advances and packaging/assembly/testing advances to reach a 'generally acceptable price point' - the problem is that some of these require actual R&D.

<warning-rerun>One issue that many folks cannot get their head around is the s-l-o-w EV ramp. If folks are not demanding EVs [you will not see them lined up all night, around the block, and anxiously awaiting the new model EVs]. The slow demand ramp will result in a slow 'price improvement ramp'... <end warning>

Ivan Kirkpatrick
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Fuel cells?
Ivan Kirkpatrick   9/16/2011 3:41:36 PM
Maybe fuel cells can substitute for batteries.  They are a little more efficient I think than an IC engine.    Better in terms of some but not all emissions.  Same problems though in terms of cost.  That would at least allow usage of the new wheel motors and whatever else came along.

As for electrified roadbed, that would take a a lot of infrastructure changes and limit the utility.  I think in similar terms whenever I look at a large NASA rocket.  All that fuel  and mass just to get a pretty small fraction of the total vehicle weight up to orbital speed, 17,500 mph.  An electrified horizontal launcher would not have to carry the fuel in along with the payload. 

The simple matter is, we need better batteries that cost less.  I just don't see a silver bullet here.

Charles Murray
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Re: Energy Storage is the Heart of the EV
Charles Murray   9/16/2011 3:20:41 PM
You're definitely correct that economies of scale will drive costs down. So -- brace yourself -- we have to go back to the experts for projections on this. When we talked to Michael Holman, research director at Lux Research two weeks ago, he said: "Through 2020, we see the cost falling to around $400 or $500 per kilowatt-hour. It will bottom out no lower than $400." As is always the case, however, there is no complete argreement on this. In 2009, the National Academy of Engineering projected that lithium-ion battery prices would hit bottom at $500/kWh in 2030. The question is: If your 40-kWh electric car battery costs $20,000, or even $16,000, is that low enough?

TJ McDermott
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Re: Energy Storage is the Heart of the EV
TJ McDermott   9/16/2011 3:17:21 PM
You are not wrong, but it's a Catch-22.  Increased demand will reduce costs, but to increase demand costs must be lower.  "That's some catch, that Catch-22" to quote Yossarian from the movie, and you can't say it any plainer than that.

All that you mentioned (motor refinements, manufacturing & chemistry improvements) are all evolutionary steps to existing technology.  None of them will help break the Catch-22.

To make EVs become solidly popular, a power source with the energy density of gasoline is necessary.  Batteries do not have that.

Maybe a fresh look at the problem is necessary.  What if the electrical power were available in the road-bed (think slot cars on twin tracks at Christmas time).  Then you don't need to carry a large battery around; a small one would be enough to permit crossing from charge track to charge track.  There's no need to plug in to recharge, because the cars are always "plugged in".  The concept bypasses the energy density problem entirely.


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