# Re: [EVDL] Estimating costs: Check my logic



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Steve I think your logic is good but their are a ton more costs to add 
to the ICE that will really tip the balance in favor of your conversion.
Tune Up costs so many cents per mile.
Oil and Lube every 3 to 5,000 miles
Transmission check-up.
Radiator Flush
I'm just trying to remember what the Jiffy Lube guy tried to pull on me 
the last time I put my car in for a simple change.
He tried to run me a $300.00 bill when all I wanted was to have him 
change my transmisson fluid.

I'm sure there are more things but wear and tear on an ICE is one of the 
greatest hidden costs that everybody forgets to figure in. With all 
those moving parts and computer controls you need a real expert with 
expert prices sometimes to keep it all running. At least that's what 
the repair industry trys to sell. Your electric will most likely not 
have as many problems and most of the battery/cable problems you can fix 
yourself in an hour and with a lot less parts costs that say oh you need 
a new temp sensor or carb or distributor etc.. etc....

Lloyd Wayne Reece
1981 Lectra Centauri
Las Vegas, NV 




> Steve Kobb wrote:
> 
> >Here's a cost estimate for the energy that I'll use in my 2002 S10
> >conversion.
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

If you are going to factor in the EV's battery life/maintenance. Then you have to factor in the ICE's maintenance. Oil, plugs, wires, antifreeze, parts that wear out.

You should take it out to 100,000 miles so you can compare each over a long period of time so you can get all of the maintenance involved with an ICE.

Also you say work is 16miles away, so you should be using 32 miles a day. Unless you work a 24 hour shift. 


> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On
> Behalf Of Steve Kobb
> Sent: Thursday, May 01, 2008 12:34 AM
> To: [email protected]
> Subject: [EVDL] Estimating costs: Check my logic
> 
> 
> Here's a cost estimate for the energy that I'll use in my 2002 S10
> conversion.
> 
> Critiques and confirmations are both welcome.


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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Looks good to me, but you are not including some maintenance costs that are
particular to an ICE. How about oil changes, spark plugs and wires, air
filters, coolant changes, belts and hoses..etc
-- 
View this message in context: http://www.nabble.com/Estimating-costs%3A-Check-my-logic-tp16992820p16993235.html
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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Are you going to charge at work?

If not, your DOD will be around 48% which looks like somewhere around 
1200 cycles.

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Your logic is just fine; my short commutes mean that I
save very little as well. However, it doesn't take
into consideration the benefits that you provide to
human health, and the planet. Most of the time, we
only look at the bottom line that's _easier_ to
quantify.
peace,
(;-p



> --- Steve Kobb <[email protected]> wrote:
> 
> >
> > Here's a cost estimate for the energy that I'll use
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

I am kinda new to this. 

What is DOD, and why do the cycles drop the more you charge the battery? I assume a cycle is the number of times a battery will take a charge before it dies.



> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On
> Behalf Of Matt C
> Sent: Thursday, May 01, 2008 10:27 AM
> To: Electric Vehicle Discussion List
> Subject: Re: [EVDL] Estimating costs: Check my logic
> 
> Are you going to charge at work?
> 
> If not, your DOD will be around 48% which looks like somewhere around
> 1200 cycles.
> 
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev



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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

I agree. : )

For me it has never been about cost but less impact. : )

If it were bottom line only then I'd still be driving my old VW Beetle.





> Bob Bath wrote:
> 
> > However, it doesn't take
> > into consideration the benefits that you provide to
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

I do not use the cost of the batteries by it self in calculating the cost 
per mile. I consider the cost of the batteries as the cost of the equipment 
like the rest of the car.

Now if a person is going to change out there batteries after each drag 
racing, or once a year or once every two years, because they are driving a 
full discharge cycle per day or less, and you replace the battery pack that 
has a life shorter than the vehicle itself, then that person may consider 
the battery cost.

I lease a car, and I may change it once a year, just to get something 
different. This saves the wear and maintenance on my classic cars that I 
may only drive once in a while which all of them are over 30 years old.

The amount of driving I do a day with the EV, which may be 5 to 15 minutes 
per day at a average speed of 15 mph which is all in residence areas, it 
takes me a month or more to complete one discharge cycle.

I normally top off the batteries about once a week which they may be still 
be above 20% DOD and charge them to only to the maximum voltage setting and 
have the battery charger shut at 5% DOD.

At once a month I may take them to 0% DOD. According to the cycle life 
chart, my batteries would last me 29 years. The last set lasted me 12 
years, but I change them, because I wanted something different.

Many people replace there vehicle every 5 years, because they wanted 
something different.

I think I still have some of that $0.33 a gallon gas in one of the tanks in 
one of my cars which I freshen up with a pint of the new stuff about once a 
year.

Distill water is now $0.59 a gallon which I use about one gallon per 100 
miles. Now, would that not be 100 miles per gallon.

Roland






----- Original Message ----- 
From: "Steve Kobb" <[email protected]>
To: <[email protected]>
Sent: Wednesday, April 30, 2008 10:33 PM
Subject: [EVDL] Estimating costs: Check my logic


>
> Here's a cost estimate for the energy that I'll use in my 2002 S10
> conversion.
>
> Critiques and confirmations are both welcome.
>
> *********************************************
>
> My office is 16 miles from my home. I drive there and back 5 days a week.
>
>
> It takes approximately 300 watt-hours to drive 1 mile.
>
>
> 300 wh per mile * 16 miles = 4800 wh
>
> Green Mountain Energy charges me approximately $0.15 per killowatt-hour.
>
>
> I have to put in a little more energy than what I take out for driving, 
> just
> because of the inefficiencies of energy transfer.
>
>
> 4.8 * $0.15 = $0.72 * 1.1 overcharge factor = $0.792 consumed power per 
> trip
>
> My pack consists of twenty-six 6-volt batteries -- a total of 156 volts.
> Manufacturer: US Battery Model: US2000. This pack cost me $3384.
>
>
> Pack capacity is 129 amp hrs at the 2-hr rate, according to a US Battery
> table entitled "Ampere Hour Capacity".
>
> This table is available at
> http://www.usbattery.com/usb_images/USB%20Ampere%20Chart.pdf
>
> 4800 wh divided by 156 volts = 30.77 amp-hours.
>
> 30.77 ah divided by 129 ah = 23.85% DOD (Depth of Discharge).
>
>
> 23.85% DOD results in a projected longevity of 2800 cycles, according to a
> US Battery chart entitled "Expected Cycle Life vs. DOD".
>
> This chart is available at
> http://www.usbattery.com/usb_images/cycle_life.xls.pdf
>
> $3384 divided by 2800 cycles = $1.2086 battery cost per trip
> Total energy cost of trip = $0.792 consumed power + $1.2086 battery cost =
> $2.00 per trip (or cycle)
>
> $2.00 divided by 16 miles per trip = $0.125 per mile
>
> vs.
>
> Using mileage figures from http://www.fueleconomy.gov/:
>
> My 1999 Infiniti gets 19 mpg city and 26 mpg highway.
> I'll use 20 mpg.
>
> 16 miles divided by 20 miles per gallon = 0.8 gallon per trip
>
> Current average local price as reported by 
> http://www.houstongasprices.com/:
> $3.49 per gallon
>
> At $3.49 per gallon, one trip has $2.792 fuel cost.
> $2.792 divided by 16 miles per trip = $0.1745 per mile
>
> Per mile cost differential: $0.0495
>
> 32 miles per day times 5 days per week times 50 weeks = 8000 miles per 
> year
> 8000 times $0.0495 = $396 fuel savings per year (assuming that gas stays 
> at
> $3.49).
>
>
> -- 
> View this message in context: 
> http://www.nabble.com/Estimating-costs%3A-Check-my-logic-tp16992820p16992820.html
> Sent from the Electric Vehicle Discussion List mailing list archive at 
> Nabble.com.
>
> _______________________________________________
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> 

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*



> Chad Gray wrote:
> 
> > What is DOD, and why do the cycles drop the more you charge the
> > battery?
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

DOD = Depth of Discharge
SOC = State of Charge

It is a characteristic of all lead-acid batteries AFAIK that
deeper discharge equates to fewer cycles. Also there is a phenomenon
called Peukert's Effect such that high rate of discharge (high amp
draw) results in less available power in the cycle.



> Chad Gray <[email protected]> wrote:
> > I am kinda new to this.
> >
> > What is DOD, and why do the cycles drop the more you charge the battery? I assume a cycle is the number of times a battery will take a charge before it dies.
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Doug Weathers wrote:
>


> Chad Gray wrote:
> >
> >
> >> What is DOD, and why do the cycles drop the more you charge the
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

We all have different lifestyles, and different reasons for doing the EV 
thing. For me, it's all about costs and the ease of maintenance; not that I 
don't care about the enviroment, but that is not a big deal to me. So I 
appreciate the cost analysis from Steve, or anyone else.

Joseph H. Strubhar

Web: www.gremcoinc.com

E-mail: [email protected]
----- Original Message ----- 
From: <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Thursday, May 01, 2008 7:15 AM
Subject: Re: [EVDL] Estimating costs: Check my logic


>I agree. : )
>
> For me it has never been about cost but less impact. : )
>
> If it were bottom line only then I'd still be driving my old VW Beetle.
>
>
>
>


> Bob Bath wrote:
> >
> >> However, it doesn't take
> >> into consideration the benefits that you provide to
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

You've made a few mistakes:

> I have to put in a little more energy than what I take out for driving,
-snip-
> 4.8 * $0.15 = $0.72 * 1.1 overcharge factor = $0.792 consumed power per

Looks like you are assuming that charging the batteries is 90% efficient. 
This is no where near accurate.
A typical charger might be about 85% efficient and batteries are about 70%
once you factor in equalization. This makes the total charge efficiency
about 60%

So 300wh per mile / .6 = 500 wh at the outlet.
That's $0.075 per mile or $1.20 each way or $2.40 per day assuming you are
paying for the electricity when charging at work.

> Manufacturer: US Battery Model: US2000. This pack cost me $3384.
Ouch! I think you could have got them cheaper if you bought them directly
from USBattery. They've quoted me $2268 for 20 US125 delivered to my
door.

>4800 wh divided by 156 volts = 30.77 amp-hours.
Umm, your voltage is going to sag under load, you have to calculate for
this. Probably will average around 146-148V while driving.
4800 wh / 147 = 32.65 AH
It's something to keep in mind, but not really significant to this
calculation

> Pack capacity is 129 amp hrs at the 2-hr rate, according to a US Battery
> table entitled "Ampere Hour Capacity".

Using the 2 hour rate is only valid if you are driving at an average speed
of 32 mph. I.e. it takes you 30 minutes to get to work. If it takes less
than that (higher average speed) then you should use the 1hr discharge
rate.
Again not terribly significant.

> $3384 divided by 2800 cycles = $1.2086 battery cost per trip
> Total energy cost of trip = $0.792 consumed power + $1.2086 battery cost =
> $2.00 per trip (or cycle)
>
> $2.00 divided by 16 miles per trip = $0.125 per mile

$1.20 (corrected value from above) + $1.21 = $2.41 per trip or about $0.15
per mile.
This works out to a cost savings (using your figures) of about $0.0245 per
mile.

> 8000 times $0.0495 = $396 fuel savings per year
$196 assuming you ignore the cost of maintenance on the ICE which is
typically several hundred dollars per year.

> (assuming that gas stays at $3.49).

That seems very unlikely. My guess is that we will see a slow but steady
increase in gas prices.


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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Thanks Doug for the excellent explanation! Now for my fuzzy logic. I have a feeling it is really fuzzy. I show better performance then Steve's numbers.

So you want to have a low DOD and this will allow you to charge the pack more often, but does it give you more miles over the packs lifetime?

So according to the chart if you drain you batteries every time (DOD 100%) they will only last about 500 charges (cycles). 

So if you get 50 miles for a DOD of 100% the battery pack will last 25000 miles.

If you do a DOD of 40% (40% of 50 miles is 20 miles) so 20 miles * 1475 cycles (according to the chart) = 29500 miles

If you do a DOD of 20% (20% of 50 miles is 10 miles) so 10miles * 3300 cycles (according to the chart) = 33000 miles

Say I drive to work for a year, 9-5 M-F 10 miles each way. That is 4840 miles a year (two weeks vacation included). 
100% DOD will get me 5.2 years on a battery pack.
40% DOD will get me 6 years on a battery pack.
20% DOD will get me 6.8 years on the battery pack.

I drive about 10 miles to work so if I build something with a range of 50 miles i would want to charge at work and at night so I get the 20% DOD and 3300 cycles or 33000 miles.


Is ok for me to say that a DOD of 20% of 50 miles is 10 miles? Do batteries discharge linearly?



> -----Original Message-----
> From: [email protected] [mailto:[email protected]] On
> Behalf Of Doug Weathers
> Sent: Thursday, May 01, 2008 10:56 AM
> To: Electric Vehicle Discussion List
> Subject: Re: [EVDL] Estimating costs: Check my logic
> 
> 
>


> Chad Gray wrote:
> >
> > > What is DOD, and why do the cycles drop the more you charge the
> > > battery?
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

You very much have to look at it from the impact perspective.

I haven't seen anyone put into the equation their time with some value
added. Makes the batteries look cheap.

Mark Grasser



-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf
Of [email protected]
Sent: Thursday, May 01, 2008 10:16 AM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] Estimating costs: Check my logic

I agree. : )

For me it has never been about cost but less impact. : )

If it were bottom line only then I'd still be driving my old VW Beetle.





> Bob Bath wrote:
> 
> > However, it doesn't take
> > into consideration the benefits that you provide to
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*



> John A. Evans - N0HJ wrote:
> 
> > This is where I always get confused. DOD is measured from the top,
> > correct? i.e., If I use my battery pack just a little, my DOD could be,
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Hi Joe and All,

----- Original Message Follows -----
From: "joe" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Subject: Re: [EVDL] Estimating costs: Check my logic
Date: Thu, 1 May 2008 07:45:27 -0700

>We all have different lifestyles, and different reasons for
>doing the EV thing. For me, it's all about costs and the
>ease of maintenance; not that I don't care about the
>environment, but that is not a big deal to me. So I 
>appreciate the cost analysis from Steve, or anyone else.

I too agree it's about costs. And any well built as
an EV will beat the pants off an ICE in costs/mile easily.
Conversions? Most need much more battery, EV drive
costs which makes it hard to justify them on cost grounds
but other things like fixing it yourself thus saving time,
money for a mechanic to fix it are. I built the Ewoody
because I had to put in a thermostat on my mother Pontiac
6000 which took me 4hrs for what should have taken 10
minutes, I said I could do better. My Ev's as most are, can
be repaired in 30 minutes or less. 30 minutes to rebuild the
motor!! Now if you can do brakes, some electrical you never
need a costly mechanic or have to wait to get your car
repaired!! 
And as Roland has shown, the way to low battery
costs is a long range pack!! Because you have so much range,
you only need to charge it a couple times/wk and
equalization every week or 2 greatly increases battery life
to the 7-10 yr range in some cases.
Unlike Roland I go for a lightweight EV so a 50%
battery weight EV isn't that much, just 2 golf cart packs
does the job if you can build get a glider under 700lbs. 
Some kitcars and VW bug, Karmen Ghia's , MG's, oldest
mini-pickups, ect can be very cost effective, converted for 
$2-4k and very easy on running costs under $.10/mile for
electric, batteries, ect. These with work and not driven too
fast can get 100wthrs/mile which equals about 350mpg cost
wise for fuel now. With better aero like the Karmen Ghia,
some kitcars, they can go fast too.
I'd like to say that charging lead batts right is
not as bad as Peter says. First most chargers are at least
85% eff, many PFC ones hitting 95%+. With some caps,
inductors you can even make the 85% eff ones into the 90%
range. 
Next with a good charge profile batts are much more
eff, 95% early in life, 90+% eff most of it's life and only
falling during the last 10-15% of usable, 70% range left,
life is the only time Peter's rate is correct. My guess is
he over equalizes/charges them. But most change packs before
then. So real charging eff is fairly good, at least 80-90%,
not 60% if done right. And since batts are so much of the
cost, you should make sure your batts are charged right!
But to be honest it's not supporting Big Oil, Auto,
Opec, terrorist and supporting National, economic security,
that I mostly do it. Saving money is just a nice benefit
among many others EV's can give. 
Jerry Dycus


>
>Joseph H. Strubhar
>
>Web: www.gremcoinc.com
>
>E-mail: [email protected]
>----- Original Message ----- 
>From: <[email protected]>
>To: "Electric Vehicle Discussion List" <[email protected]>
>Sent: Thursday, May 01, 2008 7:15 AM
>Subject: Re: [EVDL] Estimating costs: Check my logic
>
>
>>I agree. : )
>>
>> For me it has never been about cost but less impact. : 
>>) 
>> If it were bottom line only then I'd still be driving my
>>old VW Beetle. 
>>
>>
>>


> Bob Bath wrote:
> >>
> >>> However, it doesn't take
> >>> into consideration the benefits that you provide to
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Mathematically you have everything correct.
However, real life is a bit different.

In real life, most folks that try to push to 100% DoD on each discharge
experience FAR less than the manufacturers claimed life cycle.
There is a really simple reason for this. The manufacturer considers the
battery worn out when it can no longer produce more than 80% of rated
capacity.
If you need 20 miles of daily range and you build an EV that has a max
100% DoD range of 20 miles, the batteries will only be able to go 16 miles
when they have 500 cycles on them (80% of 20 miles).
Uh oh, you can't make your trip anymore. In fact after about 50-60 cycles
you will drop below 20 miles.

Second problem, as the battery approaches 100% DoD the amount of current
you can safely pull from it drops.

Third problem, and this one complicates the second problem, as the DoD
falls the batteries voltage ALSO falls. This means that to get the same
power out of the battery you have to pull MORE current.

So as you get closer to 100% DoD the pack voltage drops, so you have to
pull more current, only less current is available. Aghh!!

Acceleration suffers, your top speed drops, you have to keep one eye on
the volt meter to make sure you don't reverse a cell, and even if you're
careful you run the risk of reversing a cell anyway.
You end up having to creep along just to get to 100% DoD.

Now consider what happens when you design the vehicle to go 20 miles while
only pulling 50% DoD. when the batteries reach then end of their cycle
life and can only produce 80% rated capacity, you can STILL make your trip
with room to spare.
If you're really cheap, and don't mind the diminishing performance, you
can continue to use the batteries long past the end of their cycle life. 
This is how many folks manage to get 10 years out of a pack of batteries.

The problem with designing a vehicle to use only 20% DoD is that you end
up carrying a LOT of extra weight in batteries. This causes you to use
more energy for your daily commute and can have a negative impact on
handling and braking.
On the other hand, you do get lots of extra range, if you need it, and
your batteries will most likely die of old age rather then wearing out.

> Thanks Doug for the excellent explanation! Now for my fuzzy logic. I
> have a feeling it is really fuzzy. I show better performance then Steve's
> numbers.
>
> So you want to have a low DOD and this will allow you to charge the pack
> more often, but does it give you more miles over the packs lifetime?
>
> So according to the chart if you drain you batteries every time (DOD 100%)
> they will only last about 500 charges (cycles).
>
> So if you get 50 miles for a DOD of 100% the battery pack will last 25000
> miles.
>
> If you do a DOD of 40% (40% of 50 miles is 20 miles) so 20 miles * 1475
> cycles (according to the chart) = 29500 miles
>
> If you do a DOD of 20% (20% of 50 miles is 10 miles) so 10miles * 3300
> cycles (according to the chart) = 33000 miles
>
> Say I drive to work for a year, 9-5 M-F 10 miles each way. That is 4840
> miles a year (two weeks vacation included).
> 100% DOD will get me 5.2 years on a battery pack.
> 40% DOD will get me 6 years on a battery pack.
> 20% DOD will get me 6.8 years on the battery pack.
>
> I drive about 10 miles to work so if I build something with a range of 50
> miles i would want to charge at work and at night so I get the 20% DOD and
> 3300 cycles or 33000 miles.
>
>
> Is ok for me to say that a DOD of 20% of 50 miles is 10 miles? Do
> batteries discharge linearly?
>
>
>
>> -----Original Message-----
>> From: [email protected] [mailto:[email protected]] On
>> Behalf Of Doug Weathers
>> Sent: Thursday, May 01, 2008 10:56 AM
>> To: Electric Vehicle Discussion List
>> Subject: Re: [EVDL] Estimating costs: Check my logic
>>
>>
>>


> Chad Gray wrote:
> >>
> >> > What is DOD, and why do the cycles drop the more you charge the
> >> > battery?
> ...


----------



## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

If you discharge only to 50%, isn't it 1 cycle every 2 days?

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Huh?
DoD is totally unrelated to cycle frequency.

> If you discharge only to 50%, isn't it 1 cycle every 2 days?
>
> _______________________________________________
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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

In calculateing life of a pack, the person was talking about
dischargeing to 50% each day
Is that 1 cycle per day or 1 cycle every two days.
> Huh?
> DoD is totally unrelated to cycle frequency.
>
> 
>> > If you discharge only to 50%, isn't it 1 cycle every 2 days?
>> >
>> > _______________________________________________
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>> >
>> 
>
>
>
> 

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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

1 Discharge + 1 Charge = 1 cycle

As you can see there is no "day" in that equation.

If I discharge today and charge next month, it's still one cycle (a really
bad method, but still a cycle)

> In calculateing life of a pack, the person was talking about
> dischargeing to 50% each day
> Is that 1 cycle per day or 1 cycle every two days.
>> Huh?
>> DoD is totally unrelated to cycle frequency.
>>
>>
>>> > If you discharge only to 50%, isn't it 1 cycle every 2 days?
>>> >
>>> > _______________________________________________
>>> > For subscription options, see
>>> > http://lists.sjsu.edu/mailman/listinfo/ev
>>> >
>>>
>>
>>
>>
>>
>
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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

It goes roughly like this....if you have a battery that is supposed to get 300 cycles at 100% dod, and you only discharge it to 50% then you will get 300 cycles at 100% or 600 cycles at only 50% and 1200 at 25% dod...

THeory and real world results often differ....if you stay within all the manufacturer's specifications for discharge rate, and everyday has exactly the same weather conditions....if you hold your mouth just right, you may get the stated number of cycles....

If you abuse the batts by pulling too much current out of them at once, or charge them into oblivion...you will likely get fewer cycles than the theoretical value...

IF you discharge them and recharge them conservatively, have a battery management system with good monitoring, and cell balancing....you might get more...
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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*



> Peter VanDerWal wrote:
> > 1 Discharge + 1 Charge = 1 cycle. As you can see there is no "day" in
> > that equation.
> >
> ...


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## EVDL List (Jul 27, 2007)

*Re: [EVDL] Estimating costs: Check my logic*

Yes but it's still one cycle.



> > Peter VanDerWal wrote:
> >> 1 Discharge + 1 Charge = 1 cycle. As you can see there is no "day" in
> >> that equation.
> >>
> ...


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