DIY Lithium Ion 56 Volt Golf Cart Battery Conversion
You know how you've been looking and looking for something, and you finally find a good bargain, but it isn't exactly what you wanted, and you really didn't know any better, but you start working on it and it takes on a life of its own, and you end up having a great time turning it into just what you really wanted, and learning a lot to boot?
If that sentence doesn't strike a familiar note, this thread probably won't be your cup of tea, LOL. But if it does, please read on.
About 2 years ago I bought a used 2002 Club Car DS 36 V-glide rheostat drive. Batteries needed to be replaced but the guy told me that. It was all waxed up and shiny. It was a bargain, and I had been looking for a cart for a long, long time. I got it home and the wife said it was cute, even though she was sure she was going to hate it. She liked the little hub caps. We needed something to get around on the property, back and forth to the garden, thru the woods, up and down steep hills, hauling the grandkids. Fun stuff. No speed needed, just chugging along.
I believe that everything can be made better. My wife says its a sickness. Incurable. And her burden to bear.
The first thing was a new set of six, 6 volt batteries. Only $600, actually less than I was expecting. Then 4 new tires, about $130. Changing little tires has always been such a pain that I finally broke down and bought one of those Harbor Freight lawn tractor tire changers. Money very well spent!! Next was a new D&D High Torque 42A motor for $500. D&D told me a lift kit would be required because the longer motor wouldn't fit between the frame rails. I bought the motor anyway, no lift kit. Wife didn't want a lift kit 'cause it wouldn't be cute anymore. And honestly, maybe more likely to flip on some of the off camber hills we drive on. So instead, I shifted the rear axle a couple of inches to one side, used an offset wheel on the other side, and the new motor fit nicely between the frame rails. Plus the rear track is now 4" wider.
Here's a picture of the middle of that project.
The motor was great, plenty of torque, but man, a little more speed would be nice coming up some of the long hills. The 42A motor has lots of torque and is good for a LOT more than 36 volts, so I considered going to 48 volts. Luckily, my wife pretends not to notice this sort of silliness. She just rolls her eyes, and checks on her flowers. Here it really starts to snowball. If I convert to 48 volts, none of the 36 volt stuff would be usable anymore, its 16 years old, anyway. New controller, solenoid(s), brakes, charger, meters, etc. Oh, and batteries. Hmm, squeeze in 2 more 6 volt batteries at 60 pounds each, or replace all the batts with new 8 volt ones. Neither sounded good.
Not to be hampered by common sense, I started accumulating parts and pieces from eBay for the 48 volt conversion. SPM controller. new heavy duty Curtis 48 v solenoids. One for ON, and one for Forward/Reverse. A little 48volt 6amp charger. Cheap enough where its ok if it doesn't work. Zero to 5 K pot for throttle. Fuse. Meter with shunt to monitor volts, amps, state of charge, watt hours, you name it. Cheap from Hong Kong. A real pedal type parking brake that the grandkids can't accidentally bump loose!
Just when I was about to purchase new lead acid batteries, a buddy of mine visited. He is an avid bicycler, and electric vehicle enthusiast (obsessed!) I was telling him about the new 48volt conversion and needing new Lead Acid batteries. He said, "Why not go to Lithium Ion batteries?" I gave him the deer in the headlights look and muttered something about "too expensive", "too complicated", "set the cart on fire." He said, "None of that is true. I built myself an electric bicycle using Nissan Leaf lithium ion battery modules and I've put over 4,000 miles on it. A hundred mile trip is nothing." The first paragraph in this thread.... he gets it, LOL.
So that was the beginning. With him throwing chunks of information in my direction, and me researching from there, golly, there is a WEALTH of knowledge about DIY Lithium Ion battery powered "vehicles" out there.
Basically, ALL of the parts and pieces I had accumulated for the 48volt conversion would be usable. Maybe not perfect choices, but plenty satisfactory.
The LITHIUM ION BATTERIES.
Lithium Ion modules from the 2013 and later Nissan Leaf are commonly available on the internet and really popular for this type of project. They are reasonably priced and seem to last forever. Each module is about 10 pounds, charges to about 8 volts, and is rated at about 64 AmpHrs. Because the Li batts can be discharged to about 20% of full capacity without any problem, they are pretty much equivalent to a single 8 volt lead acid battery. So, that is a 10 pound battery replacing a 60 pound battery.
The Nissan Leaf uses 48 of these 8volt modules, but I will be using only seven of them.
Cost of the 7 modules was $532, total, with free shipping.
What that gives, is the equivalent of 48 volts of lead acid batteries (approx. 390 pounds?) into a package that is about 10" x 13" x 14" that weighs only 70 pounds. Plus, the max voltage is really 56 volts, so plenty of reserve on the top end. That is a 300 pound weight savings. Plus, the max voltage is really 56 volts, so plenty of reserve on the top end.
Li batteries can also be repeatedly drawn way down and still survive thousands of cycles. But there are tricks to getting long life.
Here is a picture of 7 modules, stacked up for testing. I have been running them thru a discharge and re-charge cycle to see how their performance looks. So far, I am very impressed.
The conversion will be happening during the next few months and I think it will be a lot of fun.
Next time, I promise not to be so wordy, LOL. Lots more to come!!
Lloyd
P.S. If you made it all the way thru this post, thank you for bearing with me.
You know how you've been looking and looking for something, and you finally find a good bargain, but it isn't exactly what you wanted, and you really didn't know any better, but you start working on it and it takes on a life of its own, and you end up having a great time turning it into just what you really wanted, and learning a lot to boot?
If that sentence doesn't strike a familiar note, this thread probably won't be your cup of tea, LOL. But if it does, please read on.
About 2 years ago I bought a used 2002 Club Car DS 36 V-glide rheostat drive. Batteries needed to be replaced but the guy told me that. It was all waxed up and shiny. It was a bargain, and I had been looking for a cart for a long, long time. I got it home and the wife said it was cute, even though she was sure she was going to hate it. She liked the little hub caps. We needed something to get around on the property, back and forth to the garden, thru the woods, up and down steep hills, hauling the grandkids. Fun stuff. No speed needed, just chugging along.
I believe that everything can be made better. My wife says its a sickness. Incurable. And her burden to bear.
The first thing was a new set of six, 6 volt batteries. Only $600, actually less than I was expecting. Then 4 new tires, about $130. Changing little tires has always been such a pain that I finally broke down and bought one of those Harbor Freight lawn tractor tire changers. Money very well spent!! Next was a new D&D High Torque 42A motor for $500. D&D told me a lift kit would be required because the longer motor wouldn't fit between the frame rails. I bought the motor anyway, no lift kit. Wife didn't want a lift kit 'cause it wouldn't be cute anymore. And honestly, maybe more likely to flip on some of the off camber hills we drive on. So instead, I shifted the rear axle a couple of inches to one side, used an offset wheel on the other side, and the new motor fit nicely between the frame rails. Plus the rear track is now 4" wider.
Here's a picture of the middle of that project.
The motor was great, plenty of torque, but man, a little more speed would be nice coming up some of the long hills. The 42A motor has lots of torque and is good for a LOT more than 36 volts, so I considered going to 48 volts. Luckily, my wife pretends not to notice this sort of silliness. She just rolls her eyes, and checks on her flowers. Here it really starts to snowball. If I convert to 48 volts, none of the 36 volt stuff would be usable anymore, its 16 years old, anyway. New controller, solenoid(s), brakes, charger, meters, etc. Oh, and batteries. Hmm, squeeze in 2 more 6 volt batteries at 60 pounds each, or replace all the batts with new 8 volt ones. Neither sounded good.
Not to be hampered by common sense, I started accumulating parts and pieces from eBay for the 48 volt conversion. SPM controller. new heavy duty Curtis 48 v solenoids. One for ON, and one for Forward/Reverse. A little 48volt 6amp charger. Cheap enough where its ok if it doesn't work. Zero to 5 K pot for throttle. Fuse. Meter with shunt to monitor volts, amps, state of charge, watt hours, you name it. Cheap from Hong Kong. A real pedal type parking brake that the grandkids can't accidentally bump loose!
Just when I was about to purchase new lead acid batteries, a buddy of mine visited. He is an avid bicycler, and electric vehicle enthusiast (obsessed!) I was telling him about the new 48volt conversion and needing new Lead Acid batteries. He said, "Why not go to Lithium Ion batteries?" I gave him the deer in the headlights look and muttered something about "too expensive", "too complicated", "set the cart on fire." He said, "None of that is true. I built myself an electric bicycle using Nissan Leaf lithium ion battery modules and I've put over 4,000 miles on it. A hundred mile trip is nothing." The first paragraph in this thread.... he gets it, LOL.
So that was the beginning. With him throwing chunks of information in my direction, and me researching from there, golly, there is a WEALTH of knowledge about DIY Lithium Ion battery powered "vehicles" out there.
Basically, ALL of the parts and pieces I had accumulated for the 48volt conversion would be usable. Maybe not perfect choices, but plenty satisfactory.
The LITHIUM ION BATTERIES.
Lithium Ion modules from the 2013 and later Nissan Leaf are commonly available on the internet and really popular for this type of project. They are reasonably priced and seem to last forever. Each module is about 10 pounds, charges to about 8 volts, and is rated at about 64 AmpHrs. Because the Li batts can be discharged to about 20% of full capacity without any problem, they are pretty much equivalent to a single 8 volt lead acid battery. So, that is a 10 pound battery replacing a 60 pound battery.
The Nissan Leaf uses 48 of these 8volt modules, but I will be using only seven of them.
Cost of the 7 modules was $532, total, with free shipping.
What that gives, is the equivalent of 48 volts of lead acid batteries (approx. 390 pounds?) into a package that is about 10" x 13" x 14" that weighs only 70 pounds. Plus, the max voltage is really 56 volts, so plenty of reserve on the top end. That is a 300 pound weight savings. Plus, the max voltage is really 56 volts, so plenty of reserve on the top end.
Li batteries can also be repeatedly drawn way down and still survive thousands of cycles. But there are tricks to getting long life.
Here is a picture of 7 modules, stacked up for testing. I have been running them thru a discharge and re-charge cycle to see how their performance looks. So far, I am very impressed.
The conversion will be happening during the next few months and I think it will be a lot of fun.
Next time, I promise not to be so wordy, LOL. Lots more to come!!
Lloyd
P.S. If you made it all the way thru this post, thank you for bearing with me.