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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
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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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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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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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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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: Round and round
JRoque   9/19/2011 11:19:27 AM
Hi. So everyone here is convinced that OEMs cannot get volume discounts, eh? The $1/Ah figure is for quantity 1 and at full retail price. Don't you think OEMs can get better pricing for, say, 500K sets of 24kW packs? Please. For a fraction of the cost of a purchase like that they can buy the *entire* battery factory and then set their own cell price.

Further, how much does it cost to put a temperature and voltage sensor on each cell? Battery pack enclosures? Shouldn't most of that already be part of the vehicle's chassis? LiFePO4 cells do not need specialized cooling up to 70C. If anything, a cheap heat pad under the pack can keep them warm in temperatures below -20C. That OEMs have chosen a chemistry that needs cooling is of their own doing, they have a better option.

In my opinion, the added costs of bringing cells to OEM production requirements can be easily offset by their higher purchasing volumes. Watch how in a couple of years, when the Gov incentives run out, they suddenly figure this out and then say batteries are not that expensive. Right.

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Re: Round and round
bbix   9/19/2011 11:25:06 AM
If batteries are really "only" $250/kwh, I'd expect a small but growing market for conversion jobs making the more popular non-plug-in hybrids capable of much more electric only operation.  Also many people have electric dryer circuits or gas range circuits that are in use very seldom and could be used for high amperage charging of vehicles without that extensive of remodelling.  Those are dedicated circuits today but most household circuits have more outlets on them than you can utilize simultaneously and people cope with that.  I used to hear more about the potential for zinc-air batteries but not so much anymore.  There is lots of research ongoing and we may be surprised by what wins in the end, there will be lots of dead-ends (think Solyndra and Evergreen Solar that went down what looked like exciting new routes but ended up with bankruptcy) and maybe some new billionaires (research done by scientists at major companies usually don't make scientists rich, but sometimes university research becomes idependent and does), also like with Bill Gates, sometimes its the person with the drive and cutthroat business tactics that can take someone else's interesting idea (Xerox windows GUI) and mold it into an empire (MS Windows) 

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Cost per kw-hr
reader22   9/19/2011 11:51:39 AM
I have been looking at a similar problem with solar power systems for the home.  The installed cost for the PV panels, chargers and inverter system can be over $2,500 per kw-hr of capacity.  Assuming 90% efficiency for the PV panel, charger, battery and inverter, and if you get 15 years of service, your generation cost might be as low as $0.08 per kw-hr.  Maybe.

To store each kw-hr of electricity, you need 1.25x capacity (for 80% DOD batteries) to 2x capacity (for 50% DOD batteries).  A good flooded lead-acid battery might cost $200-$250 per kw-hr capacity and give you 1500 cycles at 50% DOD.  So you spend $250 for 0.5 kw-hr x 1500 times, or $0.33 per kw-hr.

So I'm at $0.41 per kw-hr (minimum) vs $0.12 per kw-hr utilities.  I really WANT to go solar, but right now the costs are quite high.  Same with the current offerings in electric vehicles.  Why pay the extra upfront cost and still be faced with a $2500 battery cost in 5 years?

Liquids fuels are still the densest form of energy storage and easiest to handle and transport.  Until the total life-cycle cost of battery storage gets down around $0.05 per kw-hr (and doesn't depend on exotic materials from a foreigh competitor), we need to focus on ways of turning sunlight (or wind) into liquids fuels.



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Re: Oh, one more thing...
TimJones   9/19/2011 11:58:28 AM
Everything you say here makes sense, except for the spark-free or explosive atmosphere compliant part. I do not believe that a garage with a gasoline powered vehicle in it qualifies as an explosive atmosphere. If that were the case, then things like washing machines, driers, and water heaters would need to be spark-free or explosive atmosphere compliant, as these things commonly share garage space with gasoline fueled cars. I'm pretty sure sparks and even open flames are not a hazard in most garages.  Unless you keep open buckets of gasoline in your garage, of course.

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