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Offline CliffordK

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What is holding back electric car technology?
« Reply #275 on: 11/09/2011 09:39:07 »
Ee by gum, theyl be trooble down't mill if this catches on.
http://www.bbc.co.uk/news/science-environment-14852073

I thought Lithium Ion Polymer batteries have been around for quite some time.

Is this just reinventing the wheel?

http://polymerprojecttopics.blogspot.com/2010/09/lithium-polymer-battery.html
http://www.buchmann.ca/article6-page1.asp
http://www.pmbl.co.uk/lithium_polymer.aspx

It sounds like in many cases, the dry cells are not as efficient as liquid cells.
« Last Edit: 11/09/2011 09:43:52 by CliffordK »
 

Offline CliffordK

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What is holding back electric car technology?
« Reply #276 on: 13/09/2011 10:32:35 »
I stopped by the local Biodiesel/Ethanol station today, and to my surprise, a Tesla Roadster was "filling up" there.  A bigger surprise that the license plates indicated that the car had traveled over 300 miles to get to the station.

There were a couple of guys sitting at the counter that looked like they might belong to the car, so I thought I'd talk to them a bit.

While many gas stations give you a free cup of coffee with a fillup... 
Apparently it is common for the EV's to give a free fillup with a cup of coffee!

The guy called I-5 "Tesla Highway", with charging stations located about every 100 miles or so from Canada through the USA down to Mexico.  I think he said that it takes about an hour of charging per hundred miles or so.  Sometimes they would pull into an RV park, plug into the "facilities" for the night and set up a tent.  It must be an interesting way to slowly tour around, having a cup of coffee every couple of hours and talking to the locals. 

Apparently the car could take something like 60A, 220V full power for charging, but not all stations provide the rapid charging.
 

Offline Geezer

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What is holding back electric car technology?
« Reply #277 on: 13/09/2011 17:08:58 »
Apparently the car could take something like 60A, 220V full power for charging, but not all stations provide the rapid charging.

For info, RV (that's caravan in the UK) hookups provide 110V at 30A so they are capable of powering an air-conditioner (or, as they say in "Strine", an eggnishna.)
 

Offline CliffordK

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What is holding back electric car technology?
« Reply #278 on: 27/09/2011 21:03:54 »
I mentioned a couple of days ago that I had bid on an EV.

I didn't get the Gizmo, but I did get an Electric Ranger Conversion for less than the cost of the battery pack.


I'll write up some comments in a few days... 

But, the question is what is holding back electric car technology. 

Two things... so far...  and I've only had the Electric Ranger for a day.

I just got an E-Mail from my Insurance company
Quote
Cliff,

I just got off the phone with an underwriter and found out that this vehicle is ineligible for coverage thru xxxxxxxxxx. So there would be no 14 day coverage extension. We do not cover vehicles that have been converted because a conversion of this type affects many internal systems. They feel the risk of something going wrong and causing an accident is too high. I asked if there was a place that she would recommend for insuring these and she did not have a resource. If I were you, I would contact the people at the auction or the previous owner to find out where they had it insured. It may be a high risk company.

I do apologize for the inconvenience, but wanted to let you know what I found out right away.

Had I gotten the Gizmo, it may have been insurable, but it would have been much less safe of a vehicle for me, the driver.  But, I suppose that isn't the insurance company's concern.  And, with a top speed of 40 MPH (on the level), it is unclear whether it would have been legal to drive it home. 

The other issue that I'm running into.  The range is limited to about 40 miles.  Just enough to get to town, do a little stuff in town, and head home.  Assuming all the batteries are still good.

I know of one EV charging station which actually gives free power with the purchase of a Coffee.  However, nearly 40 years into the "modern" EVs, and they're just now getting charging station connection standards out. 

I believe the station uses a TESLA charger, which uses a proprietary plug that I'm having troubles finding information about. 

There is a new standard, J1772, and TESLA will likely incorporate that in their future cars.  But, then it just means more adapters, and retrofitting all of the charging stations that are already out there. 

If employers would allow one to charge the vehicles at work, or shopping malls would have charging stations so that one could charge while one shopped, then one could do well for around town driving, even with a very limited range.  Gas stations with an EV charger are fine, but who wants to sit in a gas station for a few hours? 

What this means is that one would need to build an infrastructure with businesses that ordinarily would not sell fuel.  And, monitor and maintain all the equipment.

The benefits of providing the charger isn't the cost of the power, but bringing the customer to one's business location.
« Last Edit: 27/09/2011 21:05:36 by CliffordK »
 

Offline Geezer

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What is holding back electric car technology?
« Reply #279 on: 27/09/2011 22:47:27 »
What's the total weight of the ranger? I hope they beefed up the brakes ;D
 

Offline CliffordK

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« Reply #280 on: 28/09/2011 04:27:17 »
Well...
The batteries weigh about 3/4 ton.
However, it kept the transmission, but no engine.  Obviously the electric stuff does weigh a bit, but I think it is lighter than the engine.  Does the Ranger come with Straight-4 and V-6 options?  With 8,000 miles, the 20 year old tranny still feels very tight.

Also, no coolant, and no gasoline.

So, I think that puts it EMPTY back at about the weight of the fully loaded Ranger (by specs...  one can put a lot more in them  ::) ).  Weight seems to be well distributed front to back.  However, this one has an enormous battery box in the middle of the bed.  One of the potential upgrades that I'm already considering is to put in a hydraulic dump bed (why not).  But, then build battery trays for under the bed, and possibly hide some batteries in the sides of the bed, and engine compartment.  This would lower the center of gravity which would be good, but would also probably distribute more weight towards the back (less than optimal).

The Ranger has power brakes which would be a problem as I believe they derive power from intake vacuum.  However, this pickup has an auxiliary vacuum pump that one hears turn on from time to time.

I haven't tried locking up the brakes, but it does seem to stop ok.

The other thing that it is lacking is regenerative braking.  I'll have to look at the motor and motor controller a bit more, but I would assume it would be relatively easy to reverse the power.  I assume the company that assembled the vehicle chose not to mess around with the hydraulic braking system.

The engine seems to do very poor engine braking.  I have to remember that for going down the driveway.  But, also I rarely using the parking brake since all my other vehicles have reasonably good engine/transmission braking.

Yesterday the charge indicator dropped to 1 tick below fully charged.
Today I did a 26 mile round-trip, and the charge indicator stayed at Fully Charged, although the recharging system certainly is sucking down some juice.  I'll have to do more tests with a longer range.  I've been carrying my bicycle, but I really need a tow dolly.

Hmmm, re-reading the insurance agent's e-mail, it is ambiguous on whether they will provide the customary 14 day grace period, at which point the insurance will not be extended any longer, or if they actually intend to cancel the grace-period too.

This vehicle was customized by a legitimate (but probably now defunct) business, and is essentially the same chassis that Ford later used to make their EV.  And it was owned and driven by the local electric company for two decades.  All the "safety" stuff works including the backup alarm.

I wonder if the insurance company would have dropped the insurance if I had installed a big-block V8 into the pickup?  What about the hot-rodded Model-T's that bear little resemblance to the original cars, and sometimes don't even use any stock body panels?
 

Offline Geezer

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What is holding back electric car technology?
« Reply #281 on: 28/09/2011 05:47:09 »
The Ranger comes with 4 and 6 cylinder options. (I had a four cylinder one for a while.)

I worked with a guy who had one of the electric Chevy S-10's that GM made. He never had any problems with it that I know of. Re. the braking, if you don't do a lot of city driving, I wouldn't bother trying to capture the braking energy in the battery, but you could implement a secondary retro-braking system as used on diesel-electic locomotives. They route the generated power to big fan-cooled resistor banks.
 

Offline peppercorn

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« Reply #282 on: 28/09/2011 11:53:23 »
You could look into adding a Range-extender to carry on the bed.
No idea what specs. you'd need for a truck that heavy. - You'd need to find out what power you're drawing at cruise on the highway.

Some time spent adding some aero mods might also be worthwhile. Smooth and seal the front end perhaps (should nothing like the air-flow through the engine-bay with only electric). A full belly-pan underneath plus lower ground clearance would also help a fair bit for higher speeds.
 

Offline Geezer

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« Reply #283 on: 28/09/2011 18:35:00 »

You could look into adding a Range-extender to carry on the bed.


Wouldn't he need a Ranger extender?  [:o)]
 

Offline CliffordK

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« Reply #284 on: 28/09/2011 19:11:24 »
The pickup has a digital ammeter.  I have to assume it is reasonably accurate.  I haven't taken it on the freeway yet, but will probably try that out sometime when I feel comfortable.

For ordinary driving up to about 45 MPH, I seem to suck down somewhere between 50A and 100A x 144V.  I see the power consumption spike to over 200A on hills and hard acceleration.  

It is the oddest thing driving a 5-speed transmission and an electric motor.  One gets used to downshifting to get more power.  But, I seem to get higher amp draw (and thus higher acceleration) with upshifting.

Deriving 100% of the power from a generator would take a pretty large generator.  However, if I targeted 50% of the power from the generator, and 50% of the power from the battery pack, then I should be able to do about 2-3 hrs of driving with a 5KVA generator.

Actually, the entire charging system seems to be designed around 30A 220V AC input.  But, the charger states 32A 220V input, 30A 144V output which doesn't make a lot of sense, so I really need to monitor the actual amp load.  Of course, 144V is just an estimate.  It is probably charging in excess of 15V per battery for a total of about 180V.  Anyway, that would give me on the order of a 6KVA generator requirement.  I would be reluctant to feed the system with a 20A 220V AC line voltage as it would undoubtedly trip the breaker.  However, a generator might not have the same limitation.  I just don't want to do anything to harm my charger.

The other option would be to find/make a 168V (12x14V) DC generator that I could feed directly into the battery pack.

Being a pickup, one could put a small generator & fuel tanks in the bed when needed, or it is already set up with a trailer hitch, and I believe even electric trailer brakes.

One other option to consider.  It is built around 144V with 2 banks of 12 batteries.

If I had a generator for road trips, I could dump one battery bank and save about 750 lbs.  That would pull more juice from one battery bank (and also have a higher recharge rate which could be hard on the batteries, but quicker for stops if I chose to recharge with line power).  But, the weight savings should compensate for the added generator.

The problem, of course.
On a home tinker's scale, it would be easy enough to load, unload, and rewire a dozen batteries. 
For a commercial application, the battery/generator changeover would have to be very easy.  I.E.  A way to drop (˝) the battery bank intact out of the bottom onto casters.

I'm trying to calculate the number of solar panels I could put on the hood, roof, and canopy.  It should be relatively easy to squeeze 500 to 1000W peak solar generating capacity.  If I compare that to my calculations for a generator, I'm down quite a bit...  but it would be FREE POWER, and might be enough to get one out of a bind once in a while.

streamlining would help...  I've thought about building a triangular shaped canopy rather than the typical box shaped canopy.  But, it may be something where one should just start with a designed-from-scratch car.
 

Offline CliffordK

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What is holding back electric car technology?
« Reply #285 on: 05/10/2011 21:38:39 »
I think the Electric Car technology is here.

We are now on the 4th generation of electric vehicles.

1st Gen, 1920's, Detroit Electric & others.


2nd Gen, 1970's, Comuta Car, Was the Sinclair Electric?  Plus a number of "converted" cars such as the Ranger pickup I bought.


3rd Gen, 1990's, early 2000's, EV1


4th Gen, Tesla, Nissan Leaf, etc.


GM, and other companies set the development of the electric vehicles back by 10 or 20 years by fighting the California initiative so hard. 

The NiMH batteries from the 90's would have been sufficient to power the electric cars.  Perhaps even NiCd.  Everything I've read seems to indicate that the NiCd batteries got a bad rap, but can be made to be very long lasting batteries, and are better batteries than they are given credit for.

The NiMH & EV story is a sad one, and is a failing of our legal system, patent system, and anti-trust system. 

Some companies such as BP have invested in alternative energy (Solar). 

But, it appears as if Texaco and Chevron chose to inhibit the development of new battery technology.  But, now they're missing the boat because EV manufacturers are moving beyond NiMH to Lithium based batteries.

Anyway, so the Nissan Leaf has a range of about 75 miles.
The Tesla Roadster has a range of about 200 miles (apparently with gentle driving).
And the Tesla Model S is supposed to cost $57,000 and $87,000, and boast a range of about 320 miles.

If more electric cars come out with a 200-300 mile range, the electric vehicles should be able to replace ordinary cars for 99% of people's driving, assuming people can figure out how to keep it charged up (getting good home and commercial charging stations availability is still an issue).  I still think that motels, shopping malls, rest areas, etc, all need to add charging stations.

So...  then this all boils down to economics.

I've never quite understood the economics of an ordinary car.  Why is it economical to pay $30,000+ for a new car when a used car can be had for less than $5,000?

Anyway, if you consider a 200,000 mile extended lifespan of a vehicle (probably with 2 or 3 owners).

200,000 miles / 20mpg = 10,000 gallons of fuel.
10,000 gallons of fuel * $4/gallon = $40,000 to fuel the vehicle over its extended lifespan.

If the "fuel" for the EV fuel cost equivalent is about 100mpg, then that gives an equivalent of about 2,000 gallons, or a cost of about $8,000 and a savings of about $32,000.

So, over time, the Nissan Leaf should just about pay for itself, although it is a big chunk of cash up front.
If you subtract $32,000 from the cost of the Tesla S with the extended range battery pack, one still ends up with a $50,000+ car after the fuel savings. 

The Leaf would make an excellent commuter car, or a second vehicle for a family with 2 or 3 cars, but it still is quite a chunk of change to put out for a car that may never leave one's home town.
 

Offline peppercorn

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« Reply #286 on: 06/10/2011 18:55:03 »
The NiMH batteries from the 90's would have been sufficient to power the electric cars.  Perhaps even NiCd.  Everything I've read seems to indicate that the NiCd batteries got a bad rap, but can be made to be very long lasting batteries, and are better batteries than they are given credit for.

The NiMH & EV story is a sad one, and is a failing of our legal system, patent system, and anti-trust system. 

Some companies such as BP have invested in alternative energy (Solar). 

But, it appears as if Texaco and Chevron chose to inhibit the development of new battery technology.  But, now they're missing the boat because EV manufacturers are moving beyond NiMH to Lithium based batteries.

But at the end of the 'NiMH & EV' article it's more upbeat:
"On July 28, 2009, Automotive News reported that Cobasys would be bought from Chevron and Energy Conversion Devices by battery maker SB LiMotive, a joint venture of Bosch and Samsung. At the time of the 2009 Cobasys sale, control of NiMH battery technology transferred back to ECD Ovonics. In October 2009, ECD Ovonics announced that their next-generation NiMH batteries will provide specific energy and power that are comparable to those of lithium ion batteries at a cost that is significantly lower than the cost of lithium ion batteries."


It could also overcome some of the limitations in WW supplies of Lithium as mentioned by Misery-guts Geezer here:
On a more cheerful note:

"It's Time To Kill The Electric Car, Drive A Stake Through Its Heart And Burn The Corpse"

http://seekingalpha.com/article/289828-it-s-time-to-kill-the-electric-car-drive-a-stake-through-its-heart-and-burn-the-corpse?source=yahoo
 

Offline Geezer

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What is holding back electric car technology?
« Reply #287 on: 06/10/2011 22:10:23 »

It could also overcome some of the limitations in WW supplies of Lithium as mentioned by Misery-guts Geezer here:


Of course, there is a much better way, but you'll have to wait until I file the patent (don't say anything to Graham) before I can tell you about it.
 

Offline peppercorn

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« Reply #288 on: 06/10/2011 22:53:09 »
Quote
Of course, there is a much better way, but you'll have to wait until I file before I can tell you about it.

Look forward to it [I think!?] !  (er, whatever it is!).
(as long as it's not the giant-springy boots I came up with in a dream last night!)
 

Offline CliffordK

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« Reply #289 on: 07/10/2011 04:03:39 »
But at the end of the 'NiMH & EV' article it's more upbeat:
"On July 28, 2009, Automotive News reported that Cobasys would be bought from Chevron and Energy Conversion Devices by battery maker SB LiMotive, a joint venture of Bosch and Samsung. At the time of the 2009 Cobasys sale, control of NiMH battery technology transferred back to ECD Ovonics. In October 2009, ECD Ovonics announced that their next-generation NiMH batteries will provide specific energy and power that are comparable to those of lithium ion batteries at a cost that is significantly lower than the cost of lithium ion batteries."
Yes, I noticed that. 

I think Cobasys/Ovonics shot themselves in the foot by not continuing making EV batteries.
Unless the Lithium based batteries fail miserably, I see more people moving towards Lithium batteries than returning to the NiMH.

In reality, after the California requirements were lifted, the demand for EV battery packs would have significantly fallen anyway.

It could also overcome some of the limitations in WW supplies of Lithium as mentioned by Misery-guts Geezer here:
On a more cheerful note:

"It's Time To Kill The Electric Car, Drive A Stake Through Its Heart And Burn The Corpse"

http://seekingalpha.com/article/289828-it-s-time-to-kill-the-electric-car-drive-a-stake-through-its-heart-and-burn-the-corpse?source=yahoo
Whew, a long article. 

I think the article missed on recycling.  While, a large quantity of aluminum cans aren't recycled, I would assume that over 90% of major auto components are eventually recycled. 

So, AA NiMH batteries may get into the waste stream.  However, NiMH or Lithium car batteries likely are virtually all recycled or reused. 

Let me know if you know of anybody throwing out a Nissan Leaf main battery pack, and I'll come and pick it up  :)

If one put a $1000 deposit on the battery packs, virtually all of them would get recycled.

Interesting point about the benefits to society of investing in many fuel efficient conventional vehicles vs investing in few 100% electric vehicles.
 

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Offline CliffordK

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What is holding back electric car technology?
« Reply #291 on: 13/11/2011 05:45:24 »
Oops.
http://news.yahoo.com/electric-car-battery-catches-fire-crash-test-182151795.html

It is hard to understand the actual cause of the fire.  They are recomending draining damaged batteries which is likely a good idea, but I would assume only under a very light load, so as to not heat up the batteries.

Quote from: Above Article
After the crash test, NHTSA found a coolant leak and moved the damaged Volt to a back lot, where it was exposed to the elements, said Rob Peterson, a GM spokesman who specializes in electric cars. Exposure to the weather caused the coolant to crystalize, and that, combined with the remaining charge in the battery, were factors, he said.

If a liquid coolant is involved, then it may not be an issue with vehicles that lack a liquid coolant.  Does the Tesla have a liquid coolant?

The other issue is that the battery packs often have very high voltages.  Mine runs at 144V, and that is somewhat low, with some packs at over 300V, and capable of putting out in excess of 1000A. 

In the event of an accident, don't grab the wrong wires!!!

I wonder if anybody has designed battery linkages that can be safely severed in case of an accident, perhaps isolating individual 24V cell packs.
 

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« Reply #292 on: 13/11/2011 06:12:06 »
Do not worry about your lead-acid batteries. Lithium-ion batteries are a bit different. Their contents can ignite.
 

Offline CliffordK

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« Reply #293 on: 13/11/2011 20:17:22 »
Do not worry about your lead-acid batteries. Lithium-ion batteries are a bit different. Their contents can ignite.

I was hoping to find a battery pack from a wrecked NISSAN Leaf.   :-\

Perhaps this will lead us back from Lithium to NiMH technology.

I still have the issue of a lot of power in the battery pack, and some relatively high voltage wires going from the back of the vehicle up into the engine compartment.  One could design spring-loaded knife blade links to isolate compartments of the battery bank in case of an accident.
 

Offline Geezer

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« Reply #294 on: 13/11/2011 20:37:02 »
Do not worry about your lead-acid batteries. Lithium-ion batteries are a bit different. Their contents can ignite.

I was hoping to find a battery pack from a wrecked NISSAN Leaf.   :-\

Perhaps this will lead us back from Lithium to NiMH technology.

I still have the issue of a lot of power in the battery pack, and some relatively high voltage wires going from the back of the vehicle up into the engine compartment.  One could design spring-loaded knife blade links to isolate compartments of the battery bank in case of an accident.

Yes, your batteries could start a fire, or even explode and spray acid all over the place, but I imagine there a fusible links that will pretty much rule that out.

I don't think this case with the Volt will slow things down much. Actually, I think it's a really good thing because it's getting everyone's attention before there are many vehicles on the road. I'd be interested in seeing the root cause analysis, if it's ever made available.
 

Offline CliffordK

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« Reply #295 on: 13/11/2011 22:11:50 »
Yes, your batteries could start a fire, or even explode and spray acid all over the place, but I imagine there a fusible links that will pretty much rule that out.

I don't think this case with the Volt will slow things down much. Actually, I think it's a really good thing because it's getting everyone's attention before there are many vehicles on the road. I'd be interested in seeing the root cause analysis, if it's ever made available.
You would need about a 500A x 144V DC fuse.  That is a lot of power...  It is likely that one could get a short that wouldn't trip the fuse, but would still be quite dangerous.

As far as fusible links...  does torching the lead battery posts count?

Ahhh...  here is an interesting article about removing the lithium from a battery.
http://periodictable.com/Stories/003.2/index.html

So, water and Lithium don't mix well.

Keep in mind that an ordinary car (including the Chevy Volt) carries an ample supply of flammable liquids.  I wonder what happens if the Volt has a gasoline leak that catches on fire, which then might spread to the battery pack.
 

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« Reply #296 on: 13/11/2011 23:23:45 »
You would need about a 500A x 144V DC fuse.

Fuses don't care about voltage; they only care about current. The power dissipated in a conductor is i squared R, so a "pinch point" in a circuit does not have to have much resistance to heat up really fast  :)

It also helps if the conductor happens to have a relatively low melting point as that speeds up the disconnect.
 

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What is holding back electric car technology?
« Reply #297 on: 16/11/2011 00:14:06 »
Quote
Fuses don't care about voltage; they only care about current.
Not true. A 100 amp ac fuse, rated a 110 volts ac, will not rupture properly if it ruptures in a 1000 v dc circuit. It will explode or arc over. Voltage rating is critical for fuses.
« Last Edit: 16/11/2011 00:15:53 by johan_M »
 

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« Reply #298 on: 16/11/2011 03:40:09 »
Quote
Fuses don't care about voltage; they only care about current.
Not true. A 100 amp ac fuse, rated a 110 volts ac, will not rupture properly if it ruptures in a 1000 v dc circuit. It will explode or arc over. Voltage rating is critical for fuses.

Quite right. We wouldn't want them arcing over, but they only care about voltage after they have fused. The fusing process has nothing to do with voltage (other than the small voltage drop across fuse's resistance of course.)
 

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Re: What is holding back electric car technology?
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