The Trojan TE35 I looked at on line appears to be flooded
battery? There is a TE35-Gel which is a seal battery. You might want to check
and make sure the TE35 is really sealed.
If I had a choice and had to use a lead battery it would a
gel. They have more cycle life and stay in balance better. You do need a
charger that has an algorithm for gel or you will cook them.
LiFePo4 should have four times the cycle life but I very highly doubt
this would provide 32 years of calendar life. NiMH had a projected
calendar life of 10 years but there are 15 year old NiMH batteries still going
strong. Lithium has some projecting a calendar life 10 to 15
years. This could vary a lot by how deeply you cycle the pack and how many
cycles you run. I have also heard 20 years but there is no way of knowing. Also
warmer temperatures shorten all battery chemistries calendar life. There
are many factors that affect overall performance.
I have a good friend who installed a pack of the older CALB SE 100AH
cells in an OEM Ranger EV.
He has over 30,000 miles but has not noticed any capacity loss. Before he
used LiFePo4 his best performance using lead was 15,000 miles with
significant loss of capacity before reaching that mileage. Also lost a few
batteries during that time. The actual useable capacity was far less
and the cost of the lead is 50% of the LiFePo4. So now all his use is all
costing no more then he would have paid for lead at 30,000 miles. This
does not factor in all the other advantages. He has reach his point of
payback.
When you size a lead pack you should figure not going less then 50% on
discharges for maximum cycle life. If you do your cycle life will be
significantly reduced.
What is misleading with lead is the AH claims by manufacturers. 200 amp
hours at a 5 amp load is just not how most people use batteries. With
significant loads your 200AH rated lead is really closer to 100AH. If you expect
to get close to the claimed cycle life with lead your use should be 50% of that.
So 50AH of capacity DOD would be your best chance at maximum success.
You could do about the same thing with a CALB 60AH cell. Your cost would be
reduced by 40% of the 100AH cells and it is highly likely to still way
out last the lead pack.
What is the amp load and for how long?
Don Blazer
In a message dated 8/18/2013 9:34:14 A.M. Pacific Daylight Time,
roberttroll hotmail com writes:
Just a few quick points.
I just pulled prices off
Google for a simple comparison.
The trojans TE35's are sealed so one
should not have to worry about acid damage.
A typical set of
trojan batteries last upwards of 8 years depending on how well they were cared
for. If there is indeed a 4x improvement in life-cycle between the two
batteries that would mean one battery CALB should last 32 years in standard ET
use?
No matter how much we all love our ET's the odds of our
tractors having a useful life at the age of 72 is slim.
I would
be interested in knowing what your cost is. Please send me a PM. Right now my
I-5 needs a new pack and i am looking at spending a low of $480 for a sams
club pack, to a high of $900 for some interstates. If i could get 10 new
england winters out of the CALB pack i would be more then happy. Heck if i can
keep the ET going another 10 years i would be happy. It just bothers me that
these are made in china as i like to keep my money local.
>
> To compare value its not that simple as adding up the
initial costs.
>
> The CALB 100AH cell has 114AH of capacity.
This would be taking the cell to
> 2.5 volts which I don't recommend.
If you only go down to 3 volts a cell,
> you will still have 100AH of
capacity and less then a 90% discharge. For
> long life a 80% DOD would
be better, about 3.1 volts to provide about 2000
> cycles until your
capacity is around 90AH.
>
> When a battery is no longer able to
provide 80% of its rated capacity most
> use this as the end of its
service life. Myself I would not replace a 90AH
> battery.
>
> I have not been able to find the data sheets on the T35 that provide
much
> cycle life information.
>
> It would appear about
600 cycles in the T35GEL if used at 80% SOC. They do
> not state what
the end of cycle life capacity is. I have seen some lead
>
manufacturers use 60% for end of service life. I have never seen very high
> lead cycle life, with deep discharges, or heavy loads.
>
> If your using lead under cold conditions your not going to have any
where
> near the rated capacity. At 40 degrees (F) your useable
capacity is 80% at
> 20 degrees it drops to 60%. As your useable
capacity drops your loads have a
> much greater impact on cycle life.
If your in a warm area with lead you
> will have more capacity but less
cycle and calendar life.
>
> Also flooded lead has a much higher
self discharge rate. So your
> maintenance is also greater when not in
use.
>
> Need more information but I would expect at least a 4X
improvement in
> LiFePo4 cycle life over lead. So your 1200 dollar lead
pack in the long run is
> really 4800 dollars. In time, using lead, you
far exceed the cost of
> LiFePo4.
>
> As far as
recycling. Yes right now since LiFePo4 has such a long service
> life
there is not going to be a lot of recycling. However with all the cell
> phones, lap tops and all the other portable electronics. There is
going to
> be a lot of lithium recycled. Not that you should throw it
away but lithium
> batteries are not as hazardous as lead acid.
>
> On hazards I would be careful as not all lithium is safe. We
had painted
> the OSU solar car and provided a pack of A123 cells all
at no cost. The next
> year they wanted more capacity so they did not
use LiFePo4 cells. I advised
> them at the time this is a great risk.
>
> Here are the results
>
>
http://www.gazettetimes.com/news/local/osu-student-gets-out-just-in-time/art
>
icle_803a17e6-afd8-11e0-bedd-001cc4c03286.html
>
> Since then
A123 became a sponsor of them. We did refinish their replacement
> car
at no charge. I was glad to see no one was killed in an EV.
>
>
Don Blazer
>
=
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