A little help on a 48 volt upgrade path please.

[Sir Nuke]

Originally Posted by Great white north

If you want maximum range and life of battery go with 8 -6 volt set up
Best way to go I have 260 amp /hr .Crowns .. ... Yes. You have a little extra weight
But that is offset with life of battery and range .. ... I would not even consider going 8 volt
Go with DPI charger ... And auxiliary 12 volt battery in bag well

[Great white north]

If you have a winch you will not want a voltage reducer ... A separate auxillary battery is still the best bet

[h20fow1er]

Originally Posted by Great white north

If you want maximum range and life of battery go with 8 -6 volt set up
Best way to go I have 260 amp /hr .Crowns .. ... Yes. You have a little extra weight
But that is offset with life of battery and range .. ... I would not even consider going 8 volt
Go with DPI charger ... And auxiliary 12 volt battery in bag well

So you have both the accesory and number 8 battery in the bagwell? I'll be honest, I like that area for storage. Also with the rear seat I have getting to that battery to water it will be a PITA. I'll go look and see if I can find your build for more ideas.

Thanks for the thoughts. Anyone else?

[scottyb]

Unfortunately some of the mathematical gains from eight batteries is lost due to the additional weight.

[JohnnieB]

Originally Posted by scottyb

Unfortunately some of the mathematical gains from eight batteries is lost due to the additional weight.

The bottom line is that there are trade-offs that should be taken into consideration when deciding on pack voltage and what voltage (and AH) batteries to use.

Not everybody has the same needs or desires or setup, so what works well for someone may not work as well for someone else.

I went with seven 6V-245AH batteries to get the range I wanted, but the local laws changed and I can no longer get to where I wanted to go on my cart, so I no longer need a 30+ mile range.

By pure chance, I discovered that 42V maxes out the RPM for my motor with the tire height I'm running, so going to 8 x 6V for 48V meant I'd be able to spin the motor fasted than the manufacturer's max recommended RPM.

Then the Alltrax introduced the XCT controller family that has the option of user selectable RPM limiting and if and when they release EZGO version, I'll be able to go to 48V and limit the max RPM with the controller.

By going to a 6 x 8V 48V pack, I'll loose a few pounds in battery weight and gain some mid-range torque, so the cart won't slow as much on steep hills.

I'll gain low and high end torque (speed) also, but I've already got more low end torque than my tiny turf tires have traction so I'll have to do some tweaking to compensate for it and with a controller that limits RPM, a speed increase due to more high end torque, is more or less a moot point.

So when my current set of batteries need to be replaced, I'll probably go with a 8 x 6V pack, or maybe Lithium (if the prices come down enough).


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The above gibberish is a rough overview of the various factors I'm taking into consideration while making plans for the inevitable battery replacement that is hopefully a couple years down the road.

[scottyb]

I prefer 6/8v T890. The gains in efficiency allow such a pack to go a bit farther than the original 6/6v pack. and you drop (about) 135 pounds. The power to weight ratio is always at work in these little carts.

[Great white north]

I understand power to weight ratio is a consideration ..Scotty ... . But for life span of battery ... And range ... Also ease of charging ( 6 volt chargers easily available if you have a low pack ... And need to charge one ... or two -- 12 volt.
Easily available ... Have yet to see a 8 volt or 16 volt charger ) I'll take the hit
On a little extra weight ... In my case I still see loads of range .. And when or if I upgrade motor .. I'll see more gains
Oh and by the way all my 6 volt batts are under the seat , only auxiliary 12 volt batt in bagwell
Cheers!

[scottyb]

Cheers

[h20fow1er]

So the Trojan 890 simply do not seem to be available in my area. I've reached out and called Kansas City, Colombia MO, and even reached into St Louis. The Trojan T875's rule the market I am in.

I did find the Crown CR-190's. they are about $15 cheaper than the trojan 875's. How much difference is there between the QUALITY of the crown and trojan batteries? Using Johnnies cheat cheet above, the crown seems like a no brainer. Especially when you look at an almost 12% gain and a $90 savings.

What am I missing?

[scottyb]

I like the Crown batteries