# Advise on new build



## Ziggythewiz (May 16, 2010)

Easily possible, not too tough. 144V (45) 0f 100AH cells would do what you want for ~$5500. 

The minimum you would need is 120V (38-40 cells) of 40AH cells (you'd have to limit the performance via the controller to go easy on the batteries), but it'd be better to do 60AHs and double them up when you can.


----------



## gblass1 (Dec 21, 2012)

Ziggythewiz said:


> Easily possible, not too tough. 144V (45) 0f 100AH cells would do what you want for ~$5500.
> 
> The minimum you would need is 120V (38-40 cells) of 40AH cells (you'd have to limit the performance via the controller to go easy on the batteries), but it'd be better to do 60AHs and double them up when you can.


Thanks for the reply. Unfortunately due to finances I'm going to have to go with lead. Would the same apply with lead ?


----------



## Ziggythewiz (May 16, 2010)

Before going with lead, consider getting a loan or something to go the lithium route. Lead costs lots more in the long run and really wastes a ton of time. You could get a small lithium pack that would easily meet your needs (not your wants) for $2k.

What is your budget for batteries? What kind of lead are you looking at?


----------



## Zappo (Sep 1, 2011)

gblass1 said:


> Thanks for the reply. Unfortunately due to finances I'm going to have to go with lead. Would the same apply with lead ?


With the short distance to work, you could get by with lead but I would advise against it.. If at all possible, you need to try to go lithium. You will never be completely happy with the lead. If you are like me, you will be grinning ear to ear every time you drive if you go lithium.


----------



## tomofreno (Mar 3, 2009)

gblass1 said:


> Thanks for the reply. Unfortunately due to finances I'm going to have to go with lead. Would the same apply with lead ?


Lead would easily work for this short commute. If you live where you have cold winters your range will suffer greatly with lead when cold, so you will have to size your pack with that in mind, or use heaters to keep the batteries warm (>50 F). If you don't push them hard, and you use traction, or golf cart, type batteries they may last you 3 -4 years. I think you will be lucky to get 1 - 1 1/2 year out of cheaper Sam's club or similar that are not made for traction applications. I use lithium cells myself, but if lead will work for you, and you realize the limitations, what the hey. If you want decent acceleration, 144V would be better. A 120V lead pack will be a bit slow reaching your > 50 mph, but will do it. Check around the "garage" here (tab at upper right of the screen), and on evalbum.com for saturns with lead batteries to see what kind of performance they get with different pack V's. You may find that a set of good quality traction batteries will not be that much less expensive than lithium, especially considering you will have to replace them in a rather short time.


----------



## gblass1 (Dec 21, 2012)

tomofreno said:


> Lead would easily work for this short commute. If you live where you have cold winters your range will suffer greatly with lead when cold, so you will have to size your pack with that in mind, or use heaters to keep the batteries warm (>50 F). If you don't push them hard, and you use traction, or golf cart, type batteries they may last you 3 -4 years. I think you will be lucky to get 1 - 1 1/2 year out of cheaper Sam's club or similar that are not made for traction applications. I use lithium cells myself, but if lead will work for you, and you realize the limitations, what the hey. If you want decent acceleration, 144V would be better. A 120V lead pack will be a bit slow reaching your > 50 mph, but will do it. Check around the "garage" here (tab at upper right of the screen), and on evalbum.com for saturns with lead batteries to see what kind of performance they get with different pack V's.


Thanks for the reply. At the current time lead is my only option if I'm going to do this conversion. My plan it's every week I'll take the money I would have spent on gas and put it aside. This way by the time the lead dies in 3-4 years I'll have the money for the lithiums.

I checked out the other Saturns and they are using 120-144 packs. To keep the weight down I'll probably go with the Trojan T-875. Any recommendations on a 110 volt ac charger ? I'm getting the impression the charger for lead is not as critical as for lithium.

Thanks
George


----------



## Zappo (Sep 1, 2011)

George,

You are correct. There are more options available for charging lead. Some people have even gone with individual chargers for each battery. It all comes down to how much you want to spend and how creative you want to get (and how much room you have to pack it all in, of course).


----------



## Ziggythewiz (May 16, 2010)

You'll want to look for a charger that can support charging for both the lead and the lithium since you plan to upgrade, or at least one that can be reprogrammed somehow.


----------



## gblass1 (Dec 21, 2012)

I don't know if this is crazy or not but yesterday when I was in Home.Depot they had a Ryobi inverter style generator for $600.00. Seeing as my lead pack will work for my daily commute but not much more would using this generator as an onboard power source to charge the batteries make sense for longer trips ? It weighs about as much as one battery and is 2000 Watts. I realize it won't keep up with the discharge rate from driving but it should help to slow down the discharge.

George


----------



## Ziggythewiz (May 16, 2010)

Then you would have an extra inefficient gas powered car.

If your car had a range of 15 miles with no generator, and you were driving at 45 mph...adding the generator would let you drive an extra 3 miles (assuming the generator is 2000 watts continuous and not peak).


----------



## gblass1 (Dec 21, 2012)

Ziggythewiz said:


> Then you would have an extra inefficient gas powered car.
> 
> If your car had a range of 15 miles with no generator, and you were driving at 45 mph...adding the generator would let you drive an extra 3 miles (assuming the generator is 2000 watts continuous and not peak).


So I am crazy lol. I'm trying to understand all the electrical stuff and reading everything I can find but I guess I'm just a mechanical guy.

Thanks again for pointing me straight

George


----------



## dragonsgate (May 19, 2012)

gblass1 said:


> Thanks for the reply. At the current time lead is my only option if I'm going to do this conversion. My plan it's every week I'll take the money I would have spent on gas and put it aside. This way by the time the lead dies in 3-4 years I'll have the money for the lithiums.
> 
> I checked out the other Saturns and they are using 120-144 packs. To keep the weight down I'll probably go with the Trojan T-875. Any recommendations on a 110 volt ac charger ? I'm getting the impression the charger for lead is not as critical as for lithium.
> 
> ...


I have been running 18 Trojan T-875 eight volt for years and have had no problems. I am moving 2,760 pounds and easily get 20 miles per charge and can squeak 30 if need be so lead is doable. In spite of what I just told you I would recommend that you go lithium while you are doing your build. If you use lead you will likely have to beef up the suspension. Then if you go lithium later you will have to readjust the suspension and probably redesign and build new battery boxes taking extra time and money.


----------



## tomofreno (Mar 3, 2009)

If you aren't already aware of it, there is another EV website, EVDL. This is a link to their forum:
http://www.evdl.org/archive/index.html


Seem to be more people there still using lead acid batteries, and knowledgeable on their care. For example they have some info on lead acid batteries, chargers, and monitors here (missing some of the newer charger offerings such as Elcon):
http://www.evdl.org/lib/index.html

I think the Elcon chargers are made by this company:
http://www.hztiecheng.com/english/

I have been using their sealed and isolated 400W DC/DC for 3 years without any problems.
Edit: Dealers on the RHS of the screen carry chargers, e.g: http://www.evolveelectrics.com/Elcon Chargers.html
They also carry Manzanita, which are more expensive but more flexible (adjustable CC/CV voltage and charge current. 


The Lee Hart batt bridge is a simple monitor. Gizmo added a voltage gauge to it:
http://2003gizmo.blogspot.com/2011/07/battery-pack-balance-monitor.html

Actually, I think flooded lead acid batteries are more trouble than LiFePO4 cells, due to things like corrosion, hydrogen gassing, regular checking of water level...but they have been used by many for many years in conversions and of course in many more forklifts. Some people report 6 years or more life if they baby them, which it sounds like you could with your commute.


----------



## dougingraham (Jul 26, 2011)

gblass1 said:


> I don't know if this is crazy or not but yesterday when I was in Home.Depot they had a Ryobi inverter style generator for $600.00. Seeing as my lead pack will work for my daily commute but not much more would using this generator as an onboard power source to charge the batteries make sense for longer trips ? It weighs about as much as one battery and is 2000 Watts. I realize it won't keep up with the discharge rate from driving but it should help to slow down the discharge.
> 
> George


To act as a range extender and keep the battery charged at highway speeds you need about a 20kw generator. With a 10kw generator, good planning and frequent stops you can make around 300 miles in a 10 hour day. With a 20kw generator you can pretty much drive as far as is physically possible. A $600 genset might do 2kw so you would need 10 of them to maintain your battery at highway cruising speed. I looked at home depot and see they have a 17500 watt gen set for $2700. I wonder what fuel consumption is at full rated output and how un green such a thing is?


----------



## gblass1 (Dec 21, 2012)

dougingraham said:


> To act as a range extender and keep the battery charged at highway speeds you need about a 20kw generator. With a 10kw generator, good planning and frequent stops you can make around 300 miles in a 10 hour day. With a 20kw generator you can pretty much drive as far as is physically possible. A $600 genset might do 2kw so you would need 10 of them to maintain your battery at highway cruising speed. I looked at home depot and see they have a 17500 watt gen set for $2700. I wonder what fuel consumption is at full rated output and how un green such a thing is?


Ok sounds like the generator was a bad idea lol.....like I said the electrical side of this is my weakness.

George


----------



## dougingraham (Jul 26, 2011)

gblass1 said:


> Ok sounds like the generator was a bad idea lol.....like I said the electrical side of this is my weakness.
> 
> George


If you want to think of it mechanically try this. What is the smallest possible ICE you could put in a car and still drive it on the straight and level at highway speed? Don't worry about acceleration because the electric drive system will handle that. You just need to be able to hold on the straight and level. Remember that you will need a fuel tank , starter system, some sort of cooling system, and an exhaust system and those have to go into the package. Then you need a generator. To give you an idea of the generator size think of the alternator on your car being able to produce 100 amps at 12 volts and this makes it a 1200 watt generator. So you need something about 16 times this size to be able to do 20kw continuous. 20kw is equal to about 27 hp. Because you would be running this thing full out all the time the cooling system is going to have to be the same size as on pretty much any car now because the power output is relatively the same in both cases for operation at highway speed. Actually in an ICE it needs to be a little larger for those hot days when you are climbing mountains.

Now once you have all of this to keep your batteries charged you will be running into overheating issues with the series DC motors because they can't shed all their waste heat for hours on end. A water cooled AC motor would be almost a requirement.


----------

