# Battery Status After Two Years



## el ohmbre (May 28, 2009)

Hello,

My questions are at the end of the information.

I did a Chevy S-10 conversion two years ago and I've been driving it almost daily on my 12 mile round trip commute to work and errands on the weekends. The best range I ever got was 40 miles once and at the peak I normally got around 30 miles. Over the past two years the range has steadily declined to around 12 miles. I'm at the point where I feel the battery pack is near the end of its useful life. Or possibly, a few bad batteries are seriously affecting range.

Here are my details:

FB1-4001A Advanced DC Motor with dual shaft
1231C-8601 Curtis Controller
Elcon PFC 3000 Charger Dual Voltage
Trojan T-145 Batteries (20) 

You can see the entire project website at: www.elohmbre.com.

The finished vehicle weighs about 4,200 pounds without me in it. My commute is 6 miles each way and includes a little "up and down" driving with a total of about 50 feet elevation gain or loss depending on the direction. I hit about 15 traffic signals, top speed is 45 MPH. When I'm in areas that I know are slow, I stay in first gear, otherwise I start in first or second and shift to second. I start gently and coast whenever possible.

I've done the monthly battery maintenance as recommended and never discharged the pack below 70% capacity as recommended by Trojan. I'm a little bit disappointed with the 30 mile range but I can live with it. However, I now have two batteries with cells that show below 1.1 specific gravity after a full charge and one at 1.224. The remaining cells show above 1.3. I hesitate to replace the three batteries if the remaining batteries are going to start to fail. All the good batteries show voltage very near to 6.57 volts and the three "bad" batteries show in the range of 6.4 volts.

I charged daily if I drove the car and have fewer than 600 charging cycles accounting for days when I didn't drive at all for some reason. Trojan seems to think I should have gotten three times more cycles.

I have been in touch with Bob at EV America many times looking for things to test and every test has back negative. Everything seems to be performing within specifications.

Questions: 
1. In the group's expert opinions, should these batteries have lasted longer given these conditions or is this a normal "real-world" life span?

2. Should I replace the three bad batteries and see if the pack continues to function or should I replace the entire pack?

3. Should I consider some other battery technology besides lead acid?

Sorry for the long post but I needed to include the details to get an answer. Any help is sincerely appreciated.

Thanks
Tom
elohmbre.com


----------



## PTCruisin (Nov 19, 2009)

Questions: 
1. In the group's expert opinions, should these batteries have lasted longer given these conditions or is this a normal "real-world" life span?

Two years is about the limit for lead acid.


2. Should I replace the three bad batteries and see if the pack continues to function or should I replace the entire pack?

If you are going to replace, then replace them all. There is talk that Trojan Batteries are not as good as they used to be. I think they are being manufactured out of country now.


3. Should I consider some other battery technology besides lead acid?

Absolutely! LiFePO4 is by far a better chemistry for traction. Higher energy density, lower weight, and longer life. You could get a 120V, 100Ah pack for around $6000 and with your commute get 8 to 10 years of service.


----------



## ElectriCar (Jun 15, 2008)

Check my evalbum link below. I built an S10 in 08 and put 8500 miles on a pack of 24 US2200XC. I always added ONLY distilled water. Tap water from the sink or hose pipe has impurities in it which is detrimental to lead batteries. They performed about as good as they did when new when I pulled them. 

*The KEY to lead batteries I think is to have a quality charger to do an equalization charge frequently and only use distilled water in them. * Mine were still going strong with the exception of one that failed completely and one that lost one cell. 

I'm now about to fire up a set of lithium batteries. I felt I was approaching the end of life for them but honestly I didn't know how much longer they would last. As I said they were still doing very well but I really needed more mileage as I use mine in my business and need to make longer trips occasionally. Before I had to drive my diesel for those trips but now I won't except for the longest trips. 

If you can afford lithium, and ones large enough that you won't exceed the recommended discharge rate but occasionally, that is the way to go. Lead batteries are VERY INEFFICIENT, wasting a lot of energy in charging and discharging. In my case I tripled my mileage capability and reduced the battery weight by almost 50%!


----------



## tomofreno (Mar 3, 2009)

If you have not posted on EVDL, you should. Their are a number of people their with decades of experience with lead acid batteries. One, Roland, has gotten over 8 years out of a pack if I remember correctly. How long they last depends very strongly on how they are used and maintained.


----------



## WSJ (Sep 18, 2008)

I use a Link-10 to measure the capacity of my weakest pack batteries. Say you have one or two batteries at 30% capacity and the rest at 75% capacity, replacing the low capacity batteries could be a good choice. I use a 100 A Electronic load and the Link-10 low voltage alarm to control a solenoid, which disconnects the load at the 5.25 Volts and displays the battery AH. I have over 3.5 years on my US 8VGC pack and it’s still going strong.


----------



## dtbaker (Jan 5, 2008)

PTCruisin said:


> 3. Should I consider some other battery technology besides lead acid?
> 
> Absolutely! LiFePO4 is by far a better chemistry for traction. Higher energy density, lower weight, and longer life. You could get a 120V, 100Ah pack for around $6000 and with your commute get 8 to 10 years of service.



... what he said.  ditch the lead, you will be WAY happier, and for much longer, despite the initial sticker shock. 

If you replace lead, ya gotta do the whole pack, and consider a central watering system like flow-rite to keep water levels exact.... I have a set for sale since I have moved from lead!


----------



## el ohmbre (May 28, 2009)

Thanks everyone for the replies. I think over the long run I'll need to move to the LiFePO batteries. At the moment that's a bit expensive for my budget.

I can replace the whole pack with a different brand of batteries and see what sort of life span I get and as a very short term test, I could replace the 3 bad batteries and see how long before the remaining batteries start to fail. Either way, that's a short term solution. 

If I have 20 Trojan T-145 how do I calculate how much LiFePO battery power is equivalent? I wouldn't mind a bit better acceleration and more range if possible.

I'm committed to the electric vehicle in the long term. I've been happy with it so I don't mind investing but I just don't want to invest at the moment because of my lack of budget.


----------



## el ohmbre (May 28, 2009)

Wayne,

How many miles have you put on in 3.5 years? Is the Link-10 still available? I vaguely remember looking for one once and couldn't find it.

What type of batteries are US 8VGC?

Thanks,
Tom
http://www.elohmbre.com


----------



## el ohmbre (May 28, 2009)

Sorry for being dense but what is EVDL?

Thanks,
Tom


----------



## tomofreno (Mar 3, 2009)

> Sorry for being dense but what is EVDL?


http://www.evdl.org/archive/index.html


----------



## WSJ (Sep 18, 2008)

el ohmbre said:


> Wayne,
> 
> How many miles have you put on in 3.5 years? Is the Link-10 still available? I vaguely remember looking for one once and couldn't find it.
> 
> ...


Only 6,000 miles in 3.5 years, most trips are 10 -12 miles. I bought a back up Link-10 on eBay for about $80. I have the US 8VGC which is a 170 AH lead acid battery. It's rated for 5.6 hours at 25 amps. I can do 25 MPH @ 25 amps. 25 MPH for 5.6 hours is 140 miles.

A Lithium pack would be great, but at $12,000 with shipping and BMS I could buy 6 US 8VGC packs over a 24 year period.


----------



## peggus (Feb 18, 2008)

I would recommend that you do a load and capacity test of each battery after giving each a long slow equalization charge and water. 

Right now there is not enough data to determine what is really going on with your pack. Clearly something isn't right with the low SG cells but we don't know if the other batteries are any good. 

You could try removing the low SG batteries and testing if your range goes up.


----------



## el ohmbre (May 28, 2009)

WSJ said:


> Only 6,000 miles in 3.5 years, most trips are 10 -12 miles. I bought a back up Link-10 on eBay for about $80. I have the US 8VGC which is a 170 AH lead acid battery. It's rated for 5.6 hours at 25 amps. I can do 25 MPH @ 25 amps. 25 MPH for 5.6 hours is 140 miles.
> 
> A Lithium pack would be great, but at $12,000 with shipping and BMS I could buy 6 US 8VGC packs over a 24 year period.


How many batteries in your pack? You must get a good price on them.

Would I get more range using 8v batteries or less?

Thanks,
Tom


----------



## el ohmbre (May 28, 2009)

Thanks to everyone who replied. I decided to replace the one worst battery; the one with a completely dead cell. This was the easiest and cheapest choice so I thought I'd give it a try before trying one of the more expensive choices.

I bought a used equivalent rated battery because they didn't have any good used T-145s available. The results have been amazing. My range has almost doubled and it's almost back to where it was a year ago. I have five cycles on the "new" battery but things look good.

My goal is to see if the remaining batteries will last as long as Trojan suggests they should. I have about 600 cycles on the pack and Trojan says I should get 1,800 cycles.

Thanks again,
Tom
http://www.elohmbre.com


----------

