[Oeva-list] conversion question?

Graunke, Gary gary.graunke at intel.com
Wed Jul 16 15:49:57 PDT 2008

I have a vehicle that is in the performance range that you desire, but
it will cost more up front--you get the payback from very low (by
comparison with ICE cars) operational costs.

It cost me about $10k to convert, but it would be more like $20K these
days. In addition, I have about $15K of batteries in it:  1380 A123
systems cells (derived from DeWalt batteries (not recommended), but it's
a ballpark $ estimate). The pack weighs a mere 200 lbs. It goes about 60
miles at 35-45 mph, and more like 48 at freeway speeds. (I have driven
48 actual miles before my low voltage alarm went off, and I drove 51
miles with extra to spare). This is the bad news.

The good news is that my AC drive will last longer than I will (at age
58), and won't need brushes. If you are driving over hills, regenerative
braking is very useful at maintaining your range. (Otherwise you lose a
lot of energy using regular brakes going downhill). AC motors always
have regen braking, but DC usually does not (check the motor AND
controller). I can easily add 4 more batteries to get to 100 mile range
weighing 330 lbs and 330V (super performance) for another $10K. The A123
have enough power for winning drag races (but my car is not set up for

The A123 systems cells are supposed to last 7000 cycles (24 years of one
cycle per day), losing about 5% every 1000 cycles, or a max shelf life
of 15 years. At 7000 cycles, 10KWH, 5 miles/KWH for freeway driving (my
Insight is very efficient), that is 4.3 cents per mile. The energy costs
are less than 2 cents per mile (10 cents/KWH divided by 5 miles/KWH).
This is extremely low compared to an ICE car (add up the fuel costs
(that's right--try to predict oil prices for the next 10 years or more)
AND the wear and tear plus oil changes, filters, etc over the total
lifetime miles).

Regular LiIon batteries may have less power, require a super BMS, and
some serious safety engineering (they explode when their insides are
exposed to air). The LiFePO chemistry does not require ventilation or a
BMS for safety (still a good idea to have something).

Your mileage will vary depending on the vehicle--look for a similar
vehicle on www.evalbum.com to find the mi/KWH. Make sure your batteries
have enough power. The voltage does not matter so much--you just get
more smaller batteries. It's the total KWH that gives you the range. 

-----Original Message-----
From: oeva-list-bounces at oeva.org [mailto:oeva-list-bounces at oeva.org] On
Behalf Of Tony McCormick
Sent: Wednesday, July 16, 2008 3:10 PM
Subject: Re: [Oeva-list] conversion question?

I'll have to let the next level up experts advise you on those 
questions.  My vehicle is a 35-40 mile range, freeway capable using 
120volts of 6 volt flooded, Curtis 1231C controller which I will be 
replacing soon with a new product and an 8" ADC motor, everything except

the batteries and the charger I bought used.   see my website for

Jess & Dennis Kaprielian wrote:
> It is round trip without the possibilty of charging at work. Ok so it 
> seems AC is to expensive. As far as a complete DC kit then it's 
> probably going to be on the upper end as far as cost for the speed and

> mileage needed right? I thought AC was more effecient and could get 
> more distance out of it. but did not realize the voltage needed. So 
> where should I go for a good price on a kit and which brand of motor 
> and controller do you suggest for my application.
> Also I was thinking of using 8 or 6 volt batt's, good idea or not?
> Thank you, Dennis
> On Wed, Jul 16, 2008 at 10:57 AM, Tony McCormick <tony at notebene.net 
> <mailto:tony at notebene.net>> wrote:
>     You should reply to the list for this thread.  You replied just to
>     me.  
>     AC systems from from Metric Mind are reasonably priced but need
>     240Volts or more work of batteries to get decent range an
>     performance.  At about $249 per battery for 12V Optima's (for
>     example) that's $5000,
>     The motor kits (very compete) are somewhere between $5-10K
>     depending on the motor size.   You are going to be closer to 20K
>     for what you want in AC.  50 miles is optimistic without NiMH or
>     Lithium which are both a lot more expensive.  Is that your one way
>     trip?  If this is a work/commute can you charge at work or nearby?
>     --Tony
>     Jess & Dennis Kaprielian wrote:
>         Hi thanks for the response,
>          well i'm not totally sure what to base my budget on yet but I
>         was thinking anywhere from 7,000 to 12,000. I see after that
>         doing some searching online that the 70 mile trip range may be
>         over doing it. But 50 mile range at least will be necessary
>          and I do want freeway  speeds.  And to narrow down the
>         vehicle type  I'm thinking a '91 Jetta. I was also thinking
>         about using an AC motor.?
>         Dennis
>         On Tue, Jul 15, 2008 at 5:47 PM, Tony McCormick
>         <tony at notebene.net <mailto:tony at notebene.net>
>         <mailto:tony at notebene.net <mailto:tony at notebene.net>>> wrote:
>            What is your budget?  For that kind of speed and range you
>            need fairly expensive equipment.   The sweet spot is about
>            miles range with mixed driving and 55-60 mph.
>            --Tony
>            Jess & Dennis Kaprielian wrote:
>                Hello. First time I am writing here. I was wondering if
>                someone can tell me what a good combo of
>                motor/controller/batteries will be good for a mid size
>                2door to small four door, to be able to do
>         approximately 70mph
>                and have a 50 to 70 mile range on a charge. And if
>         there is a
>                kit for the first time converter with the same range
>         and speed.
>                Thank you for your help.
>                Dennis "new e.v.'er"
>                _______________________________________________
>                Oeva-list mailing list
>                Oeva-list at oeva.org <mailto:Oeva-list at oeva.org>
>         <mailto:Oeva-list at oeva.org <mailto:Oeva-list at oeva.org>>
>                http://www.rdrop.com/mailman/listinfo/oeva-list
>            --    Tony McCormick
>            --------------------------------
>            http://www.notebene.net <http://www.notebene.net/> &
>            http://www.backporchrevival.com
>         <http://www.backporchrevival.com/>
>     -- 
>     Tony McCormick
>     --------------------------------
>     http://www.notebene.net <http://www.notebene.net/> &
>     http://www.backporchrevival.com <http://www.backporchrevival.com/>

Tony McCormick
http://www.notebene.net &

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