Will my 36volt club cars controller handle a Lithium battery

[Porash]

I recently bought a 1994, 36 volt Club Car. At this point I don't have a manual or any electrical information about its internals.
I am thinking about converting to a 36volt 100ah lithium Lifepo4 battery.
How can I be sure that the controller will handle the lithium battery. Or should I be concerned with that?

[Porash]

After some searching I think I know the answer to my question.
the speed controller is resistor type. I was thinking something like a solid state electronic controller.

[Michael Eddie]

I think you're envisioning a solid state controller upgrade with a lithium conversion, but from your description, it appears that the cart currently has a resistor coil system. While both systems manage the speed of the cart, they’re actually quite different in how they handle power distribution and efficiency.

Resistor coil setups use a series of resistor coils to manage power, burning off excess energy as heat when you’re not at full throttle. This design is far less efficient and it doesn’t take advantage of the higher efficiency, longer lifespan, and low maintenance benefits that lithium batteries offer. In fact, lithium and resistor systems tend to conflict. Lithium batteries deliver constant power quickly and efficiently, while resistor systems are inherently inefficient and generate a lot of heat, which is a poor fit for lithium’s high performance specs.

Resistors pull a constant high current often between 50-100 amps even at low speeds. This heavy, unmanaged draw can quickly trip the BMS in lithium batteries which are built to handle efficient regulated loads that are often designed for high bursts only intermittently. Without the control precision of a solid state controller, resistor coil systems stress the lithium battery’s cells and the BMS leading to premature shutdowns and damage to the battery itself.

If you’re aiming to get the best from a lithium conversion, you might want to consider either upgrading from a resistor coil to a solid state controller (a more involved project) or selling this cart in favor of a model that already has a solid state system in place. It’s easy to see where the confusion might stem from though, the language around speed controls for older golf carts can sometimes blend together especially when discussing upgrades. When thinking about “controllers,” it’s natural to assume all carts have a modern solid state system, but older carts like yours often use resistor coils instead. Resistor coils and solid state controllers both control speed, but the methods they use to do so are fundamentally different. When it comes to upgrades, a lithium battery is perfectly suited for a solid state controller system, but pairing it with an older resistor setup will lead to issues.

[Porash]

Thank you for the comments.

Yes the cart has resistor coils.

I am contemplating the change over to solid state control with lithium battery.

My 6 volt batteries are requiring to be charged very often.
Some cells are weak and I had no luck in desuphating them.

I gave $1,500 for the cart.
My usage is only around the property. No hills involved.
Just a slight incline on the drive way near the road.
And basically I use the cart to take the trash to the pickup point on the road and get the mail from the box.

My thinking is, that I should be able to install a 36v lithium 100ah battery cheaper than I can replace the lead acid batteries.
Plus add the speed controller and items.

I don't plan on replacing the motor if I don't have to.
During the change over to lithium and solid state
I can take it apart and clean it up and put new brushes in it.


I need some guidance on selecting the speed control items though.

Do you think a Curtis motor controller would do the job? They are not expensive.

I have not found the throttle potentiometer that the throttle pedal linkage would connect to.

I just want to make the cart function better and and hopefully save $$ over the long term.

[golfcartg]

Thank you for the comments.

Yes the cart has resistor coils.

I am contemplating the change over to solid state control with lithium battery.

My 6 volt batteries are requiring to be charged very often.
Some cells are weak and I had no luck in desuphating them.

I gave $1,500 for the cart.
My usage is only around the property. No hills involved.
Just a slight incline on the drive way near the road.
And basically I use the cart to take the trash to the pickup point on the road and get the mail from the box.

My thinking is, that I should be able to install a 36v lithium 100ah battery cheaper than I can replace the lead acid batteries.
Plus add the speed controller and items.

I don't plan on replacing the motor if I don't have to.
During the change over to lithium and solid state
I can take it apart and clean it up and put new brushes in it.


I need some guidance on selecting the speed control items though.

Do you think a Curtis motor controller would do the job? They are not expensive.

I have not found the throttle potentiometer that the throttle pedal linkage would connect to.

I just want to make the cart function better and and hopefully save $$ over the long term.

Upgrading to a solid state controller and lithium setup can be more involved than it seems initially and costs can stack up in unexpected ways. Once you start down that road, you’re not just swapping batteries, you’re also factoring in the cost of a reliable high amperage controller, possibly a new throttle potentiometer (MCOR), updated wiring harness, and a lithium compatible charger. These components all add up often exceeding the initial price tag as you make adjustments to ensure everything works smoothly. Plus, once everything’s in place, the controller might also need programming to match lithium’s different discharge profile.

Considering the specific needs of your cart mostly for light property use on flat ground, a good quality set of trojan lead acid batteries could meet those needs comfortably. Plus they’re compatible with your cart’s current system which means no additional conversions or highcost upgrades are necessary to get everything running. This would bring the cart back to solid, reliable operation without going down the “rabbit hole” of a conversion project, which could end up costing nearly as much as buying a cart with those upgrades already built in I think.

1. Lithium Battery Pack (36V 100Ah)

• Recommended Specs: 36V lithium (LiFePO4) battery with at least 100Ah capacity.
• Look for a pack with a Battery Management System (BMS) capable of handling high amp draw for a certain timeframe (usually 300 amps or more for golf cart use).

2. Solid-State Motor Controller (36V)

• Recommended Brands: Curtis, Navitas, Alltrax.
• 300-400 amps for standard use; up to 500 amps if you plan to run higher speeds or more demanding terrain later.
• Some controllers require programming, either through software or an optional handheld programmer.

3. High-Amp Solenoid (36V Compatible)

• Make sure it’s rated for at least as many amps as your controller (typically 200-400 amps continuous).

4. Throttle MCOR or Throttle Sensor

• Converts pedal position to an electrical signal compatible with the solid-state controller.
• Make sure to choose one compatible with both your cart and the new controller (you may need a specific adapter if using Curtis or Alltrax controllers).

5. Lithium-Compatible Charger (36V)

• Confirm it has a specific charging profile for lithium (LiFePO4) to avoid damaging the battery. Some lithium chargers also have smart features like Bluetooth for monitoring charge levels via a phone app.

6. Battery Cables (Upgraded to Handle Higher Amperage)

• $50 - $100 for a set of high-quality 2-gauge or 4-gauge cables.
• Lithium batteries discharge at a higher current, so you’ll need cables capable of handling increased amperage to prevent overheating or resistance losses.

7. Battery Mounting Hardware and Insulators

• Secure the new battery properly; lithium batteries are typically lighter than lead-acid, so you may need different mounting brackets or stabilizers. Prevent accidental shorts by insulating exposed terminals.

8. DC-DC Converter (Voltage Reducer)

• Converts 36V battery voltage down to 12V for accessories (lights, horn, etc.).
• At least 20 amps output at 12V, if you plan on running lights or other accessories frequently.

9. Controller Mounting Plate

• If your original cart does not have a solid state controller, you may need a new mounting plate or bracket for your chosen controller.

10. Battery Meter

• A separate display or app to monitor lithium battery health, including state of charge, voltage, and individual cell balance. While lithium batteries have built-in BMS, an additional monitor can give you real time status updates and help prevent unexpected issues. Lithium battery meters should be shunt driven

11. Miscellaneous Installation Items

• Heat Shrink Tubing for added insulation on connections.
• Zip Ties or Mounting Straps to secure cables and keep everything tidy.
• Silicone Sealant to protect exposed connections from moisture and corrosion.

This list covers the basics, but keep in mind, there’s often much more to it once you get into the actual setup.

[Porash]

Thank you Golfcartg,
No doubt it is a big decision. A lot to think about.