How to find a good 6 Volt battery for $5

If you have the space to mount a 6 Volt golf cart battery, a $5 core could last for years on your tractor. When a golf cart can’t make it through the day without stranding the golfer, the pack is replaced. I have replaced many cart battery packs and found there is usually one bad battery and the rest are fine to use on my tractor. This is possible because the batteries in a golf cart are connected in series and the weakest battery in the pack limits the range of the cart.

The reason a golf cart battery core can be used on a tractor is the requirement to start a tractor is much different than powering a golf cart. If a tractor can start in about 10 seconds with a battery current of 100 amps, the Amp hours used are 100 times 10 divided by 3600 (seconds in an hour). This is less than 0.3 Amp hours. I have measured golf cart battery cores at more 50 amp hours. A new 6 Volt tractor battery is about 50 AH and a useable battery can be less than 10 AH. I have started engines on a battery with less than 5 AH.

A quick way to choose which core to buy is finding the battery with the highest voltage in the same pack. If they all were charged and discharged together the best battery will have the highest voltage. It may take a day or two to charge the battery before it’s ready for your tractor.

Wayne

This a discharge curve of an old 6 Volt battery logged with a BATTERY TEST SYSTEM I designed several years ago.

That is pretty good! Where would I be able to get a hold of these cores?

Informative academia. And the real world usefulness of the findings?

Dell

Check the phone book for local businesses selling golf cart batteries, golf cart repair, golf courses and recycling centers. I saw some guys at the local recycling center shoring a golf cart battery with a pipe just for fun. I may still have that battery on a tractor.

I bought a pair of new Interstate deep-cycle blemished batteries for my '98 Dodge Cummins three years ago. They were $40 ea from the Interstate warehouse.

I assume the golf cart batteries have the same construction. Most said they they wouldn't be satisfactory because they wouldn't have the required cold cranking amps.

Well, they work so well I took the extra battery from the Dodge 3500 and put it in my 660D. Both vehicles start fine on one deep-cycle storage battery even though both were equipped from the factory with duals.

Those deep-cycle batteries are very heavy and I suspect they will last a long time. They have fewer plates but those plates are considerably thicker and more durable. Probably similar to motorcycle batteries that can handle alot of heat and vibration.

I doubt if I will ever buy another automotive style battery.

Wardner,
Excellent information!
That is one of the nonsensical mysteries that has bothered me.
I could never grasp the reason a deep cell battery would not work perfectly fine in a land vehicle.
I have had salespeople actually refuse to sell me one after I told them I was going to use it in a pickup.
Dell

(quoted from post at 16:50:47 12/05/10) I bought a pair of new Interstate deep-cycle blemished batteries for my '98 Dodge Cummins three years ago. They were $40 ea from the Interstate warehouse.

[u:23be8839cd]I assume the golf cart batteries have the same construction. [/u:23be8839cd] Most said they they wouldn't be satisfactory because they wouldn't have the required cold cranking amps.

I doubt if I will ever buy another automotive style battery.

Click to expand...

A deep cycle golf cart battery provides more cranking amps than an automotive cranking battery or deep cycle marine battery. A deep cycle marine battery provides the lowest cranking amps. The popular US 2200, 6 Volt golf cart battery, has the capacity to crank a Farmall H for 1:20, at 100 Amps. provided the starter could be cooled to prevent damage. I have test data to validate the manufactures specified capacity of 232 Amp Hours.

Cranking a Farmall H for 1:20 is based on the published capacity chart, as well as my test data.
http://www.usbattery.com/usb_images/USB Capacity Chart.pdf

http://www.usbattery.com/usb_us2200xc.html

Automotive, and even so-called "deep cycle marine" batteries have the lead plates perforated full of holes. This does three things:

1. Increases the surface area for the chemical reaction, which increases the power the battery can put out (i.e. "cold cranking amps")
2. Reduces the weight of the battery. Lead is heavy.
3. Reduces the cost of producing the battery, using less material.

The battery will provide a quick burst of energy to start a car, but will not hold up well to long low draws and deep discharges. It works in a car because as soon as the engine fires, the alternator charges the battery back up.

Golf cart batteries have SOLID lead plates in them. That's why they are heavy for their size. They do not have as much surface area for the chemical reaction that produces electricity, so they don't provide as many cold cranking Amps.

The solid lead plates make them hold up better to vibration and rough treatment. Plus they last longer.

Most modern vehicles start easily enough that a golf cart battery has plenty of "cold cranking Amps."