# What am I missing?



## Elextrovert (Dec 22, 2008)

Hi guys. I’m new to this forum, but I’m really pumped on converting a car to electric. I’ve done quite a bit of homework and, unfortunately, I’m coming to the conclusion that what I want to do may not be feasible with any kind of reasonable budget. I absolutely need to use this to commute to make it worthwhile. My commute is 23 miles each way with about 19.5 of it on interstate. Around here (Nashville), if you get on the interstate, you need to push 70mph or you get run over. I might be able to tolerate 60mph. No place at work to plug in (yet) so I need the round trip and some safety factor so I’m figuring 60 miles. Problem is, by the time I work out all the calcs, I need a battery pack with around 300 Ah. No such animal. Am I missing something? Are there ways to do this or is the technology not there yet? I’d appreciate any comments/suggestions.
Gary


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## chamilun (Jun 17, 2008)

as I live in and around Nashville, and have completed my conversion, I can tell you this:

the answer is, unfortunately, no. I never noticed how many hills there are in Nashville until driving my EV. So not only do you have to overcome the driving at interstate+ speeds, you have to be able to do so with a constant grade in the road. 

I can get about 26 miles on a charge to about 20% SOC. When I am driving on more flat roads, say around Gallatin, I could get probably 40. 

144V conversion with T1275 batts, 94 eclipse


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## Elextrovert (Dec 22, 2008)

Thanks for the quick reply, Chamilun. I'm hoping someone has a recommendation that will involve something other than converting a pick-up truck to haul all the batteries. My only other hope seems to be getting my company to provide electrical outlets in the parking lot! If I could make that happen, I might have an outside shot at it. My commute from Franklin is actually about as flat as you can get in this area, but you're right. It's never completely level.


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## madderscience (Jun 28, 2008)

You are missing nothing. It is a challenge to build a lead acid conversion that can do 40+ miles at highway speeds on a daily basis.

If you can afford lithum (doubling or tripling your overall budget, at least) it should be fairly easy to get enough battery on board.

If you don't want a pickup my next suggestion would be a geo metro. As one very prolific local converter around here has demonstrated you can cram twenty or more 6V golf cart batteries into a geo metro but it will take some fabrication skills to do it. Use a 8" motor, anything smaller will overheat on the freeway and anything bigger probably won't fit. Couple that setup with high pressure, low rolling resistance tires, lowering the car and adding an air dam or belly pan to reduce aerodynamic drag and stripping down the car of any unessential weight and you should have a car that can do 55 to 60 miles to 80% dod. 

While you might not get all the way there, I'd be shooting for a battery-to-vehicle weight ratio in excess of 40%, maybe more like 50%. And use good batteries, like interstate or trojan flooded. In the lead acid category I don't think anything else will be up to the job.

Look at this car for an example as its a good example of what you might want to do if you picked a geo:

http://voltrunner.com/default.aspx

The 101 mile range claim on the website included an extra battery pack that was added for the range rally competition where this distance was recorded, so with the car's normal battery pack (still very big for the size of the car) it probably would have made about 75 miles under the same conditions.

Good Luck.


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## Elextrovert (Dec 22, 2008)

Thanks for the link, Madder! Can I call you Madder? I'm very impressed with what they have accomplished using roughly 80 Ah! It shows that what I want to do is within sight. Maybe not quite as stylish as I was hoping for, but within sight. I took the opportunity to look at your site as well. Your performance is in the ballpark I'm trying to achieve with basically the same setup as the Metro, but a bit more stylish! I'll keep studying!


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## madderscience (Jun 28, 2008)

You can call me Madder. Or Brian.

Keep in mind the distance was achieved at 55mph, not 60+mph you said that you need, so that will negatively affect range too. And also the distance was achieved in a competition situation which meant we were all taking more risks than we might otherwise. The other big thing that helped the geo's range that I forgot to mention was that it has heated batteries, and for the range rally run they were heated up to 120 degrees which is too hot for daily use as it will cut the battery lifespans short. Normally batteries if heated are warmed up to 70-80 degrees. Heating the batteries will help range substantially in cooler temperatures.

I believe that the builder of the geo said that he had used a combined total of about 120AH at 126v off of the main pack, and 25AH at 132v of the second pack that was added for the range rally run giving him about 200WH/mile which is pretty darn good.

In the same range rally where the geo did 101 miles with the heated batteries and 2nd battery pack (1700lbs of lead, total) I got second place with 66 miles off of 1250lbs of lead and no battery heaters. (it was a 50 degree day, dry but a little windy). I did not have a watt hour meter like the geo, but if I make a reasonable estimate that I used 100AH off my cooler batteries at 126v I came in at a little under 200WH/mile as well.

I regularly drive my car around 30 miles at speeds around 55mph and the DOD usually stays above 50% though it will go below that on cold, windy, rainy days. If I were building the car for a 45 mile freeway round trip I'd throw out all pretenses and cram 3 more T-105s into the car: one more could go up front with some cajoling, and the trunk could hold 2 more sacrificing most of the remaining space. That would get me up to 144v and 1400lbs of lead. The MR2 would need yet heavier springs and beefier brakes in the back but otherwise could probably take the load.

Good Luck; definitely do your research.


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## Elextrovert (Dec 22, 2008)

Thanks, Brian. Yes, I realize that at best we're talking borderline for what I would like to do. This is....well....not good enough, because when I head off to work in the AM, I want to have some reasonable expectation of making it home in the PM. It means I'll need to have some success getting the company I work for to install an outlet or two in the garage for EVs. Based on what I've heard from you and Chamilun, the half-commute of 23 miles is very attainable with good safety factor. If I can get a good charge over 9 hours or so in the parking lot, I'll be set.

For what it's worth, the vehicle I'd like to do is the current body style Toyota Celica. Good aerodynamics. It's only slightly heavier than your MR2 in stock form and plenty of room for batteries since it has an expendable back seat (weight savings). Should be EZ to get 144V+ with appropriate controller. I'm looking at 6V golf cart batteries. Should be possible to approach the 40% battery/vehicle weight ratio you've suggested without opening up the transaxle, but competition flywheel and lighter wheels are definite considerations.

By the way, your website on your MR2 is excellent!


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## sailfish11 (Sep 15, 2007)

Another thing to try is to get your employer to let you charge at work. You should check your state to see if there are any incentives to help you -- or help your employer install a charging station. In NY, the state will chip in 50% of the cost of the charging station. That, coupled with some good PR for helping save the environment may convince your employer to help you out.


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## Tom Thomson (Jun 11, 2008)

Elex
When calculating range, don't fall into the same trap I did. The batteries which I used had an amp/hr rating based on a 75A discharge rate (I think others are similar) but in my Porsche conversion I am seldom under 120A. Some weird thing called the "Peukert effect" comes into play and reduces the amp/hrs which you can draw. There are fomulas which you can use to correct for the amp load you expect to use. My 192 AH Interstates suddenly became only 100 AH Interstates. 
tommyt


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## ElectriCar (Jun 15, 2008)

Elextro, I hate to rain on your parade hopes but you MUST know this about an EV and keeping warm! I've got an S10 144V, 33kw pack with electric 1500w heater. It puts out 2000w at 144V with the fan on Hi. You're in Knoxville, a little colder on average than my Spartanburg, SC. 

One thing not mentioned here or on this site much is the "COLD" factor. If you plan to drive in the winter up there you're going to have to use something other than electric heat, at least using lead and much more pack kw than on spring and summer days. 

I've got just 200 miles on mine, 8 days or so of driving! During that week it was warm the first few days and I got great mileage, even a trip of maybe 15 miles on the freeway, *warm daytime driving*. 

On one charge I had 30 miles of city driving, averaging 35-40mph and still reading at or near 144V pack voltage (I didn't have my SOC meter in then). Now I felt really confident of my range being maybe 50-65 miles/charge. And the batteries weren't even broken in (25-50 charges to do this I've read). 

Then it turned cold, 32-38 degrees for the last few days. After getting all pumped up due to excellent range on warm days I made three trips totalling about 28 miles, *at night*. I thought I could easily make it back to the shop for a recharge as all my lights but the headlights are LED now. So it appears that cold driving with the heat on and I'm getting maybe half or just over half my expected max range on warm days. 

On my way to the shop, it rather quickly begins losing power and within 1/2 mile of noticing, it dies. I'm near half way from my house, it's 5 more miles to the shop at this point. All this is night driving and I'm using my heater only as needed, I'd say 60% of the time.

Luckily batteries will rejuvenate after a few minutes and you can drive a little more. I had to do this about 4 times to get 3 miles to a place I could recharge a bit.

I know it's going to be colder where you are and on those long stretches you're going to have to go slow and use propane or such to keep warm. I've read that increasing from 50 to 65mph uses about double the power if I remember correctly. Using my truck and pack as an example, driving at 60mph your cutting your trip capacity close to half. Figure in a half reduction again due to the cold effect on the battery and you'll get maybe 15-20 miles using NO electricity for heat. 

One thing I don't know much about though is taking a generator along. How much that would help and would it be worth it? 

You're likely going to have to go with a LI pack or best case recharge at the office all day while you work. But then again you must consider, what if you get to work and have to leave quickly and return home? You know you'll have to go home early at some point due to weather, family emergency or such.

Best of luck and keep us posted with your progress if you proceed. EV knowledge and experiences is of utmost importance to us DIYers.


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## chamilun (Jun 17, 2008)

I'll second that. my 26 mile range was in the dead of cold, so 35-40 is attainable without opportunity charging.

as far as keeping warm, consider using the liquid heater instead of the ceramic. you can preheat the car, and stay remarkably warm.

I have two offices, and just need to figure out a way to get a plug to the car. Maybe an extension cord, but that just seems too messy.


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## Elextrovert (Dec 22, 2008)

To be honest, I was planning on no heat or A/C and being a "fair weather" commuter. To me, that means 60 degrees and up. However, I might also shy away from 90 degrees and higher just to keep my...uh...."personal aroma" in check. I was figuring colder weather would cut the range, but I wasn't figuring cutting it in half! Anyway, if I stick to fair weather and get my company to supply some electric, I should be OK.

The issue I'm dealing with now is to convince myself that it's worthwhile to spend a bunch of man-hours (fun) and ~$13k (not so much fun) to convert a car that I don't own yet to full electric. All to reduce the vehicle's performance and utility to questionable levels. I like the idea of being "greener". I'm just not sure I want to be that green. I'm not trying to spark a debate or argument here. I'm just wrestling with that internally.


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## Technologic (Jul 20, 2008)

Elextrovert said:


> The issue I'm dealing with now is to convince myself that it's worthwhile to spend a bunch of man-hours (fun) and ~$13k (not so much fun) to convert a car that I don't own yet to full electric. All to reduce the vehicle's performance and utility to questionable levels. I like the idea of being "greener". I'm just not sure I want to be that green. I'm not trying to spark a debate or argument here. I'm just wrestling with that internally.


 
That seems awfully high priced... for any conversion.

I hate to say it, but maybe you should be looking into building a ground up, super light, purpose built lithium car for this duty... Afterall the one I intend to make will cost almost HALF that much, and get a 120-150mile range.

Granted it's going to be about 10 times the work for me.


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## ElectriCar (Jun 15, 2008)

Technologic said:


> That seems awfully high priced... for any conversion.
> 
> I hate to say it, but maybe you should be looking into building a ground up, super light, purpose built lithium car for this duty... Afterall the one I intend to make will cost almost HALF that much, and get a 120-150mile range.
> 
> Granted it's going to be about 10 times the work for me.


I've seen some electric kits that are super light but are they interstate worthy? I'd like to be wrapped pretty good in steel on that road! 

RE $, I've got 11G in the conversion alone on mine using 24 LA US2200 batteries. The extras like rebuilding the tranny, new sound and paint job etc have run the bill to around 15G. One thing I paid extra for was a 240V charger so I could recharge quickly but you can't opportunity charge. 

I'm also working on a BadBoy charger. It's basically a drop cord, bridge rectifier with a heat sink and an extra cord, maybe put it in a box with an amp meter to help determine the extra cord needed to keep the amps down. I've used it when it died in the cold weather a few weeks ago. It's just rigged now but it got me to the office!

Re *driving with no heat*. You could use an oil filled heater which I understand are very good at holding heat long enough to make your trip to work. I've picked up one but I got to take it back. It's the Honeywell at Wal-Mart with an electronic control. It won't work with a timer. They have a cheaper one with a manual knob I'm going to get.

Merry Christmas, Happy Honnakah or whatever holiday you celebrate!


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## jstack6 (Jul 26, 2007)

size and weight. If you want a low cost high miles per charge you have to pick a very light efficient vehicle. Some 3 wheelers like the aptera are a great goal, they are only $26 K but only sold in California so far. A bicycle is also a choice.

As you increase size and weight the cost goes up. That why some of us have to drive a hybrid. It's all the advanced batteries we can afford at this time. 

So you have small light vehicles, or hybrids. No wonder Toyota has sold over 1.5 million prius vehicles. They aren't perfect but get better with every version.

The 2010 (avail Jan 2009) is 30% better mpg than the last models. 

My bicycle is 100% lithium and goes over 50 miles on a charge for 8 cents. The bicycle only cosst $799 at Rmartin in Austin Texas !


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## Technologic (Jul 20, 2008)

ElectriCar said:


> I've seen some electric kits that are super light but are they interstate worthy? I'd like to be wrapped pretty good in steel on that road!
> 
> RE $, I've got 11G in the conversion alone on mine using 24 LA US2200 batteries. The extras like rebuilding the tranny, new sound and paint job etc have run the bill to around 15G. One thing I paid extra for was a 240V charger so I could recharge quickly but you can't opportunity charge.
> 
> ...


Sure there's tons of kits that can go 70mph... hell there's tons of ideas in my head for super sleek 2 seaters that could acheive 90-100mph with a Cd of like 0.1 ( less than a 1/3 of the drag of a normal sedan), obviously drag on a normal sedan is a waste of energy and space.

I know what you mean by Nashville running you over, I went there recently from NC, it's terrible traffic and people are suicidal.

You could use a ton of different heating methods, and cooling ones... using heated/AC seats is actually extremely efficient for body temp and also take like 1/5th the wattage a car does...

Not to mention the most horribly inefficient heaters still only use 1kwh... for a hour of heating. Meaning you'd still have about 10 times that amount in reserved power.... By this summer or fall I should be offering fiberglass and kevlar reinforced crumble zone kits from the molds I make... just for the hell of helping the EV community.

Don't count on buying out of the box in the next 5 years from any company, Aptera included. I'd rather be surrounded by kevlar tensionally reinforced fiberglass than steel anyday.

$11k in batteries just makes me vomit a little. I could do so so so much if I had that kind of money right now... I could get like 300 miles per charge out of this 2 seater I've been blueprinting up, and still have enough to make an extra clone of it


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## Bottomfeeder (Jun 13, 2008)

Technologic said:


> Not to mention the most horribly inefficient heaters still only use 1kwh... for a hour of heating.


I don't think there is such a thing as an inefficient heater. Every watt of electricity put into a heater most certainly leaves as heat.


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## Technologic (Jul 20, 2008)

Bottomfeeder said:


> I don't think there is such a thing as an inefficient heater. Every watt of electricity put into a heater most certainly leaves as heat.


 
Sure there's lots of inefficent resistive heating methods... induction is vastly more electrically efficient than resistance heaters.

Efficiency in this is how much BTU's is produced per watt... which can fluctuate widely between heater designs.


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## Bottomfeeder (Jun 13, 2008)

Technologic said:


> Sure there's lots of inefficent resistive heating methods... induction is vastly more electrically efficient than resistance heaters.
> 
> Efficiency in this is how much BTU's is produced per watt... which can fluctuate widely between heater designs.


I guess I don't understand. What form does the energy take if not heat for those "inefficient" designs? Is it increasing potential energy somehow instead?


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## Technologic (Jul 20, 2008)

Bottomfeeder said:


> I guess I don't understand. What form does the energy take if not heat for those "inefficient" designs? Is it increasing potential energy somehow instead?


 
Say you had a heater that was using 1kw

While another heater that was using 200 watts via induction. Induction heating uses magnetism to heat a core... while resistive heating runs it through a resistive wire (often some kind of iron) that then uses it's own resistance to cause heat.

Induction is almost free, very few losses, and the energy is transfered nearly perfectly through the wire (ideally you'd want to use superconductors for this)...

Where the energy "goes" is just purely into inefficiency (heating elements that are resistive often have 360 degree heating, which is almost pointless for a car heater). Likewise heating via. magnetism allows you to shove up the switching rating (which doesn't necessarily cost more energy) which actually heats it faster and more efficiently. It's odd how magnetism works like this, but really there's no real wattage requirement just magnetic "power" which comes from both amperage, number of turns in the coil, and frequency of the switching.

Using magnetism is almost one of those "free energies" in physics. It's like gravity and appears to be wholly forceful without necessarily any entropy.

Ie. if you super heated a bar of steel to 1000 degrees F (a low wattage induction heater could do this in 1-2 seconds) you could then just recycle the air through the car past this coil, once every 2-4 minutes or less...

This would be far more efficient than pumping air over a heating element... far far far more.

Also inductive heaters can be one directional if you need them to be (ie. not heating the cold air on the back side of this recycling but only next to the fan itself.

Also heavily electrically insulative things (besides ceramics of course) tend to be very thermally insulative... harming their abilities to "give their heat" to the air.

In induction you're using the magnetism of the steel itself as energy to produce heat... steel also is fairly heat conductive (far more than resistive wires).

Ideally you're right, but photons and other things are given off in large quantities by resistive wires, as well as waveforms... not to mention the whole thermally insulative thing I've just discussed.


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## peggus (Feb 18, 2008)

Technologic said:


> Sure there's lots of inefficent resistive heating methods... induction is vastly more electrically efficient than resistance heaters.
> 
> Efficiency in this is how much BTU's is produced per watt... which can fluctuate widely between heater designs.


Inductive heating is only more efficient because it applies the heat directly in the object to be heated. So perhaps if you have a metal plate in your ass, an induction heater in the seat would be more efficient. By the way, induction heating IS resistive heating.

That said, since we're talking about cabin heating here, it does not matter much what method is used to heat the heating element. It is always going to be at worst 100% efficient, well, unless it's glowing in which case you're loosing some energy in the form of light.

How that heat is then applied to heating the cabin/driver does affect efficiency, i.e. leaky ducts, circulate air vs outside air, seat heaters etc.

Now I said at least 100% efficient; heat pumps such as A/C units can exceed 100% since we define efficiency in this case as (heat energy output) / (electrical energy input). Heat pumps use electrical energy to pump heat from one place to another.


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## Technologic (Jul 20, 2008)

peggus said:


> Inductive heating is only more efficient because it applies the heat directly in the object to be heated. So perhaps if you have a metal plate in your ass, an induction heater in the seat would be more efficient. By the way, induction heating IS resistive heating.
> 
> That said, since we're talking about cabin heating here, it does not matter much what method is used to heat the heating element. It is always going to be at worst 100% efficient, well, unless it's glowing in which case you're loosing some energy in the form of light.


 
Please reference my post on heat transfer to air from the heated element itself. The nickel elements often used are going to lose a lot of electricity into resistive gains from the heat insulation as well.

In either case the point was, that heated/cooled seats is the best way, as it makes people warm/cold the fastest, most efficiently, and without losing tons of it into the air of the cabin and out of the windows of the car. Especially in the case of air conditioning, cooling the sweat on your body via A/C'd seats is probably the best way to feel "cold" during the summer.

I wouldn't call induction heating resistive... magnetism is a different kind of "resistance". Granted magnetism and electricity are sorda the same thing.


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## peggus (Feb 18, 2008)

Ah, yes. Magical magnetic power and free energy....

For reference Inductive heating works by a rapidly changing magnetic field inducing electrical currents in the object to be heated. The object has to be conductive, this is why a inductive stove does not burn you. The induced electrical current gives rise to IIR losses which heats up the object in question.



Technologic said:


> Say you had a heater that was using 1kw
> 
> While another heater that was using 200 watts via induction. Induction heating uses magnetism to heat a core... while resistive heating runs it through a resistive wire (often some kind of iron) that then uses it's own resistance to cause heat.
> 
> ...


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## Technologic (Jul 20, 2008)

peggus said:


> Ah, yes. Magical magnetic power and free energy....
> 
> For reference Inductive heating works by a rapidly changing magnetic field inducing electrical currents in the object to be heated.


 
Hmmmmmmm how do you figure it's electrical current and not the magnetic polarity itself that's causing the heat, which is why steel heats up vastly faster than copper/aluminum in an induction heater. The magnetism and rapid polarity shifts cause heat, at least this is what I have always read. Back EMF from the coil causes the other metals to heat up in the coil from what I understand.

I didn't mean to imply free energy, since the energy comes directly from the power in the coil, however, this kind of heating is often extremely efficient, in the mid 90% range usually (vs. say 25% range for a heating element). 

There is a difference between magnetism and electricity, granted the difference is similar to the difference between lasers and light, however, that doesn't mean they're the same thing (in fact they're very different).

While magnetism can make electricity and visa versa, that doesn't make electric resistivity the same as magnetic heating from polarity shifts.

Transforming AC into another frequency is actually realitively easy, I've also read information that seems to suggest the higher the switching you can get the quicker/hotter/better induction works, at least with steel.

Anything can be heated in an induction coil btw, electrically conductive or not... there's super conducting coils that can levitate frogs etc, yet they aren't heated in such a structure (because it's not switching).

However, overlooking the entire point once again, that steel and the surface area of the piece in an induction heater could be made to heat up/give off it's heat EXTREMELY efficiently. Say a honeycomb with air running between it inside an induction coil.


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## peggus (Feb 18, 2008)

You're right, there is also magnetic hysteresis losses in ferromagnetic materials such as steel contributing to the heating. However since copper and aluminum etc are not ferromagnetic it is purely resistive heating taking place in most metals.


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