Precedent 2008.5 DIY Lithium build

[Bbbbrass]

My friend lives in a nearby beach town and has a rental condo that he also includes a golf cart with. His renters drain the cart, and have killed the lead acids. My experience with my cart and the cost delta have convinced him to build his own Headway pack with me for about $800, rather than replace with new PBs. (Please note, I advised him the cheapest option is the tested Hawker AGMs that Palmetto Battery Pros sells. That would have been under $400. They claim it won't fit 4 in the tub, it will. Anyways...)
I'll try to do some pics of the process and improvements as we go, both as a resource and to track what we do!

[augiedoggy]

Nice thing about lithium is the bms can be set to shut the battery down at whatever percentage of state of charge a person desires.

[Bbbbrass]

Cart as it stands currently.

Not sure why those are sideways, they aren't on my computer...

[Bbbbrass]

Originally Posted by augiedoggy

Nice thing about lithium is the bms can be set to shut the battery down at whatever percentage of state of charge a person desires.

Exactly. Desire is to limit capacity that renter can use, so we can just log into BMS and back to charge.

[Bbbbrass]

Out with the heavy old 4x12 setup. Those things are beasts! My regular PB battery removal handle didn't seem to line up securely, so a little ratchet strap work and presto I had a shoulder strap to lift with! (Not pictured yet)

One of the batteries was only a year old, and still great. 2 others were 3 years old, and after desulfating and long charging still only hold at 12.5V. They will join the scrap pile with lucky battery 4 that has a literal hole in it. Picture to be added later....

These cables will have the ends chopped, be assessed for corrosion, and get new terminals when I find a use for them. New 4 or 2AWG going in!

[augiedoggy]

at least the scrap price for batteries has gone up... I got over $60 for my old batteries when I dropped them off at an interstate battery a couple month ago..

[Bbbbrass]

Here is a list of what is going in the cart, please understand some items may be a different brand/model slightly. This is all stuff I've used before and know works. One consideration is that with the location, salt air and water intrusion is a much higher likelihood that may be regularly considered. (I have zero affiliation or sponsors to be clear. I make no money in any way from these links. Please consider using a site sponsor, particular shoutout to Cory at Palmetto Battery Pros!)

Charger - CC/CV Power Supply will be mounted in the cart, so it can recharge anywhere. Only 8Amps so it doesn't need additional cooling, will be set and glued in place at 57V to maximize cell health. This item is also useful for individual cell testing/top balancing.


Plug for charger - Ok, I haven't used this one before but it was recommended by people here on BGW as fitting well.

48V-12V DC-DC Converter - I prefer 13.8V models, but this one is keyed to ignition so renters can't accidentally run things down as easily. I also haven't used this exact model before, so I'm hoping it's fully potted like the 4 wire model I have.

48V Bus Bars - The key to a clean and easy to work on install. Be careful of Amazon ones. I've used several with success, but they are often only rated at 70A per stud, and list the total (like 250A) in the listing. These guys are way more solid, but you do pay for shipping (Dexter from CC is also awesome).

12V Fuse Block - Makes it easy to add on more accessories later, and keeps you from starting fires on accident. This is one where close to saltwater matters. I've gotten cheap versions that claim to be for marine use, and they rust in a few months.

12V Wiring - Don't cheap out here either! Get ABYC approved stuff.

Primary Wiring - I don't have a link for all my old welding ground cables I scored, but these are the smallest stuff I use.

BMS - Don't even talk to me if you don't use one. And it better have low temperature disconnect. I know Headway claims they can charge at -10C, we ain't gonna test that. I really like the JBD/Xiaoxiang BMS. Make sure you get the LiFePO4 version! The Overkill (another great guy) app is even better. This is a larger version of what I have used, and is seriously beefy! They upped the contactor, added a precharge resistor, and now include a fuse. I would have no issues pushing 300A continuous and max of 500A in this. We won't peak above 250A, and I don't constant load will ever exceed 100A for more than 25 seconds.

Cells - For under $500 you can get 40AH that can push 600A continuous.

[augiedoggy]

your links arent working for me.

I do use that same bms with good results so far..
with different 90ah prismatic cells I got for a bit more at $620 shipped

you might even want to consider adding one of these to that bms
https://www.aliexpress.us/item/32568...andl_shipto=US
I find it easier at times then messing with the bms app

I looked hard at those headway cells before too..
Just shows there more than one way to skin a cat while on a budget.

[jasonojordan]

Links did not work for me either but I picked out the part numbers from the link that was generated to find most of what I believe you had intended to link.

This is the shore charging port I used for my conversion on my Club car. Has worked pretty well for me and has a nice cap to protect the connection points while not in use.

https://www.amazon.com/dp/B009ANV81S...roduct_details

Originally Posted by Bbbbrass

Here is a list of what is going in the cart, please understand some items may be a different brand/model slightly. This is all stuff I've used before and know works. One consideration is that with the location, salt air and water intrusion is a much higher likelihood that may be regularly considered. (I have zero affiliation or sponsors to be clear. I make no money in any way from these links. Please consider using a site sponsor, particular shoutout to Cory at Palmetto Battery Pros!)

Charger - CC/CV Power Supply will be mounted in the cart, so it can recharge anywhere. Only 8Amps so it doesn't need additional cooling, will be set and glued in place at 57V to maximize cell health. This item is also useful for individual cell testing/top balancing.


Plug for charger - Ok, I haven't used this one before but it was recommended by people here on BGW as fitting well.

48V-12V DC-DC Converter - I prefer 13.8V models, but this one is keyed to ignition so renters can't accidentally run things down as easily. I also haven't used this exact model before, so I'm hoping it's fully potted like the 4 wire model I have.

48V Bus Bars - The key to a clean and easy to work on install. Be careful of Amazon ones. I've used several with success, but they are often only rated at 70A per stud, and list the total (like 250A) in the listing. These guys are way more solid, but you do pay for shipping (Dexter from CC is also awesome).

12V Fuse Block - Makes it easy to add on more accessories later, and keeps you from starting fires on accident. This is one where close to saltwater matters. I've gotten cheap versions that claim to be for marine use, and they rust in a few months.

12V Wiring - Don't cheap out here either! Get ABYC approved stuff.

Primary Wiring - I don't have a link for all my old welding ground cables I scored, but these are the smallest stuff I use.

BMS - Don't even talk to me if you don't use one. And it better have low temperature disconnect. I know Headway claims they can charge at -10C, we ain't gonna test that. I really like the JBD/Xiaoxiang BMS. Make sure you get the LiFePO4 version! The Overkill (another great guy) app is even better. This is a larger version of what I have used, and is seriously beefy! They upped the contactor, added a precharge resistor, and now include a fuse. I would have no issues pushing 300A continuous and max of 500A in this. We won't peak above 250A, and I don't constant load will ever exceed 100A for more than 25 seconds.

Cells - For under $500 you can get 40AH that can push 600A continuous.

[jasonojordan]

Originally Posted by augiedoggy

I looked hard at those headway cells before too..
Just shows there more than one way to skin a cat while on a budget.

They defiantly would work well for someone who does not drive a ton of distance at one time.