Six 12 volt Gel Cells in a 36v TXT

[sportcoupe]

JohnnieB is right about range, I was very wrong when I said range would be reduced at 72v compared to 36v with the same batteries. I should have remember that too since I am running 72v golf cart.

FYI, my 36v motor held up to 72v ok but did run warm during extended rides.

[Commitclothing]

I'm all about speed! And if run time isn't significantly reduced by running at 72 volts, it's definitely an option I'm interested in. What should I expect to spend on a controller for 72 volt system? I hear a lot of people upgrading to the Altrax.... If I can pickup a decent controller for under $5-600, and all I have to do is swap out my cables, I'm down!!

I'd rather spend $150 bucks extra and have a cart that will blow the doors off of most everyone else's!!

Thanks again for your help everyone :)

Sean

[sportcoupe]

72v major parts list

1) New controller - Alltrax SMP 72400 with ITS throttle input $519
http://www.evdrives.com/product_p/con-spm72400.htm

2) New charger - GEM charger would work fine if you change plug or direct wire it

3) Main contactor - 72V $55
http://www.evdrives.com/product_p/sol-sw180s.htm
precharger resister
http://www.evdrives.com/product_p/kit-pcr-1kt.htm
diode
http://www.evdrives.com/product_p/kit-csd-3s.htm

My ezgo went 26mph at 72v on 22" tires with stock motor and the above Alltrax controller.

[Great white north]

I guess I'm old school I would stay with tried and true 6 volt Trojans or Crowns
Whether 36 volt or (8 -6 volt ) 48 volt for overall range
Cheers !

[JohnnieB]

Originally Posted by Commitclothing

I'm all about speed! And if run time isn't significantly reduced by running at 72 volts, it's definitely an option I'm interested in. What should I expect to spend on a controller for 72 volt system? I hear a lot of people upgrading to the Altrax.... If I can pickup a decent controller for under $5-600, and all I have to do is swap out my cables, I'm down!!

I'd rather spend $150 bucks extra and have a cart that will blow the doors off of most everyone else's!!

Thanks again for your help everyone :)

Sean

I said you would have about the same run-time with either voltage arrangement, but I didn't say it would be a good run-time.

It will be less than what a stock 36V cart would have.

---------
Like GWN, I'm old school too, but I also include Deka, Exide and US Battery on my list.

[sportcoupe]

Well if you can get alternative batteries for pennys compared to Tojans then that can be the great decision maker. For example my 180ah, 72v pack cost $36 and I have 21 miles range.

[JohnnieB]

Originally Posted by sportcoupe

Well if you can get alternative batteries for pennys compared to Tojans then that can be the great decision maker. For example my 180ah, 72v pack cost $36 and I have 21 miles range.

Not everybody has access to less expensive alternatives, but if you do, go for it.

For the rest of us, all we can do is comparison shop in our local area for the highest AH at the lowest price.

My comparison list currently has about three dozen entries for 6V batteries. (9 brands with 2 - 7 models per brand)

[sportcoupe]

I wouldn't make his cart 72v unless I knew the amp-hour rating of his GEM 12v gel batteries. If the OP can post pictures of said battery we can look up the spec.

For example, my 120ah, 72v pack only returned me a 12 mile range. Far less then a 36v cart with T-105 batteries.

[Commitclothing]

<br>
Charger I have:
<br>

[JohnnieB]

Looks like a Deka 8G31. (97.6AH @ 20Hr rate)
Here is a spec sheet for it.
Note the the VPC (Volts per Cell) is 2.30V to 2.35V.

Also attached is the charge curve the Lestronic II uses.
Note the voltage climbs into the 2.45VPC to 2.79VPC before it shuts off automatically.

That is a good charger for wet-cells, but goes too high for Gell-Cells.