How to convert Club Car from lead acid to Lithium batteries

[Michael Eddie]

Let's dive into upgrading your Club Car golf cart from lead acid batteries to lithium. This is a popular upgrade for many golf cart owners these days and for good reason.

They’re lighter, which means your cart will be easier to maneuver and will have a better range since the motor doesn’t have to work as hard. They also have a much longer lifespan, sometimes up to 10 years, so while the initial investment is higher, you'll save money in the long run by not needing to replace them as often. Additionally, lithium batteries require significantly less maintenance compared to lead acid batteries, which need regular watering and equalization charges.

People are making the switch to lithium because of these benefits. They’re tired of the constant maintenance and shorter lifespan of lead acid batteries. Plus, lithium batteries charge faster and hold their charge longer, making them more convenient and reliable for those who use their carts frequently or for longer trips.

How do I upgrade my Club Car?

When upgrading, one common issue you might encounter is if your cart is equipped with an On Board Computer (OBC). The OBC, which came standard on most 48V Club Cars from around 1996 to 2014, manages the charging cycle of lead acid batteries. However, when you switch to lithium, the OBC often needs to be bypassed because it can't properly manage the new battery type. Without bypassing the OBC, you might face running issues.

For the best results, it's recommended to upgrade to a single 48V or 36V 105Ah lithium battery rather than using multiple individual 6V or 8V lithium batteries. This approach helps with better balancing which is important for longevity and efficiency of lithium batteries. When batteries are not properly balanced, certain cells may experience overdraw or overcharge, while others remain underdrawn or undercharged. This imbalance can result in reduced performance, shortened lifespan, and potential BMS lockout.

Two highly recommended brands for lithium batteries are Eco Battery and Trojan OnePack. These companies have proven themselves with high quality products and stellar customer support. Their batteries are backed by solid reputations and are designed to handle the demands of golf carts effectively.

Along with the new battery, you’ll need to upgrade your charger to one with a lithium charging algorithm. Lithium batteries require a different charging profile compared to lead acid batteries, and using the wrong charger can damage them. A Battery Management System (BMS) is also highly recommended. The BMS monitors the battery's health, verifying cells are balanced and protecting against overcharging, undercharging, and overheating. It's important to choose a battery that can handle up to 300 amps of draw for a reasonable amount of time to make sure your cart performs well without tripping the BMS. If the BMS trips, it shuts down the battery to prevent damage, which can leave you stranded or damage your cart’s electrical system.

Here's a list of components you’ll typically need for the upgrade:

1. 48V 105Ah Lithium Battery: $1,500 - $2,500
2. Lithium-Compatible Charger: $300 - $500
3. BMS (included with most high-quality lithium batteries): Typically included
4. OBC Bypass (if applicable)
5. Charger Interlock Bypass (if applicable)
6. Battery Mounting Hardware and Cables: $100 - $200

In terms of time and labor, if you’re handy with tools and comfortable working with electrical systems, you can probably do the upgrade yourself in a weekend. However, if you’re not as confident, hiring a professional might be worth the investment. Professional installation could cost anywhere from $200 to $500, depending on the rates in your area and the specific requirements of your cart.

Will lithium give my 36v cart more speed?

If you're currently running a 36V setup and seeking more speed, switching to lithium alone won't significantly boost your speed, except for a slight improvement due to weight reduction and increased range. For a noticeable increase in speed, upgrading to a 48V system is your best bet. Most 36V golf cart motors can handle the increased voltage, providing a substantial performance boost. However, to make this upgrade, you'll need a 48V battery pack, a compatible charger, a new 48v solenoid, and possibly a heavy duty forward/reverse switch to handle the increased power. It's also wise to check your controller's compatibility with 48V for smooth operation.

How about resistor carts?

Resistor carts, which utilize a series of resistors to control speed and power as opposed to electronic solid state speed control, are not recommended for lithium battery upgrades. This is because the resistor system is inefficient, wasting a significant amount of energy as heat and not taking full advantage of lithium's benefits like efficiency and longevity. Additionally, resistor carts maintain a consistently high amp draw even at slower speeds, which often conflicts with the operating range of most lithium Battery Management Systems (BMS). Upgrading a resistor cart to a solid state system is a more complex and costly endeavor. It typically requires a MCOR throttle sensor, a new controller, and other necessary parts such as solenoids and wiring. Given these extensive modifications, it might be more cost effective and less hassle to sell your current cart and purchase one that already has a solid state setup. This approach not only saves money but also ensures you get a more reliable and modernized system right from the start.

Types of lithium batteries

Lithium ion (Li-ion) and Lithium Iron Phosphate (LiFePO4) are two common types of lithium based batteries, each with distinct characteristics and advantages.

Lithium-ion (Li-ion) batteries are widely used in consumer electronics, electric vehicles, and various other applications. They are known for their high energy density, which means they can store a lot of energy relative to their size and weight. This makes them ideal for applications where space and weight are critical factors. However, Li-ion batteries can be sensitive to temperature extremes, require sophisticated battery management systems (BMS) for safety, and have a shorter lifespan compared to LiFePO4 batteries.

Lithium Iron Phosphate (LiFePO4) batteries, on the other hand, are a subtype of lithium-ion batteries that use iron phosphate as the cathode material. They are known for their excellent thermal stability, safety, and long cycle life. LiFePO4 batteries are less prone to overheating and are more chemically stable, reducing the risk of thermal runaway (a condition where the battery overheats uncontrollably). They also tend to have a longer lifespan, often exceeding 2,000 charge cycles. However, LiFePO4 batteries typically have a lower energy density compared to traditional Li-ion batteries, meaning they are larger and heavier for the same energy capacity.

What about upgrading the charger?

You'll need to upgrade the charger to accommodate the specific charging needs of lithium chemistry, which differs significantly from lead acid batteries. Lithium batteries require a charging algorithm that includes phases like constant current and constant voltage, while lead acid batteries typically undergo three main stages: bulk charging, absorption, and float. In contrast, lithium batteries require a different approach: they begin with a constant current phase, where the charger delivers a set current until a certain voltage is reached. This is followed by a constant voltage phase, where the voltage is maintained while the current decreases, allowing a complete charge without overcharging. The danger lies in using a lead acid charger with lithium batteries, where the end stage charge rate could be too high, potentially leading to overheating and overcharging.

For post 2014 Club Car models without an On Board Computer (OBC) such as those with ERIC PowerWise chargers, you can potentially continue using your existing charger by updating it with a lithium algorithm if available. This update allows the charger to properly charge lithium batteries adjusting its cycle to match their specific requirements.

What potential issues arise when bypassing the original charging port?

Upon upgrading to lithium, you may need to bypass the original charging port to connect your new charger. A interlock is a safety feature found in some golf carts charger port that prevents the cart from operating. It helps prevent driving away with the charger still attached by sensing the charger plug. However, when bypassing the original charging port or modifying the charging system of the cart, the charger interlock may need to be bypassed (if equipped). This is because lithium chargers may not be compatible with the original interlock mechanism. If the original charging port is removed, it may shut down the cart. Bypassing the charger interlock involves modifying or disabling the circuit that prevents the cart from being disabled. It allows the cart to operate normally without the original charging port.

Accommodating headlights and accessories

For golf carts equipped with original lighting systems, Club Car typically wired a 16v to 12v voltage reducer to two 8 volt batteries or avoids using a voltage reducer and instead wires directly to a single 12 volt battery if the cart has a 4x12 volt battery setup. However, when switching to lithium batteries, it's best to remove and install a 48 volt to 12 volt reducer. This allows the entire electrical system to be powered evenly and prevents any one battery from being drained more quickly than the others, which can lead to imbalances and reduced overall battery life. Using a 48 volt to 12 volt reducer allows all accessories to receive a consistent and stable voltage.

Technical Support

Overall, upgrading to lithium batteries is a fantastic way to improve the performance, reliability, and convenience of your Club Car golf cart. I always recommend taking advantage of the technical support offered by trusted companies like Eco Battery and Trojan when purchasing new batteries. Their exceptional customer support systems are invaluable for troubleshooting, optimizing performance, and helping with a smooth transition, especially when upgrading to technologies like lithium batteries. While cheaper alternatives may seem tempting, they often lack warranties and reliable support, leaving you vulnerable to potential issues without proper backup. Our community is also here to assist you every step of the way, feel free to post in the Club Car Electric Forum if you need any guidance or have questions during your upgrade.

Offseason Storage

Storing lead acid batteries and lithium batteries for the off season requires different approaches due to their chemical makeup and care needs. Lead acid batteries need regular attention, they should be kept fully charged to prevent sulfation, where sulfate crystals form and reduce battery capacity. They also require proper ventilation and avoiding extreme temperatures to stay in good shape during storage. On the other hand, lithium batteries are easier to store because they typically have an on/off switch and a lower self discharge rate, meaning they can hold onto their charge longer without needing maintenance. It's best to store lithium batteries at around 50% charge in a room temperature, dry place to maintain their health over time. Unlike lead acid batteries, lithium batteries typically don't need regular checks or special charging routines, making them simpler to handle during periods of non use.

[Michael Eddie]

Check out this gallery featuring various lithium setups with different battery sizes and brands such as Roy Pow, Eco Battery, Allied, and Samsung. These pics showcase how each battery type looks when installed, providing a visual reference for choosing the right option and sizes for your needs.

[Michael Eddie]

Bypassing the OBC on Club Car Models

IQ and Excel Carts
For all years of IQ and Excel carts, the White and Blue wires generally work better for bypassing the Onboard Computer (OBC). In these models, the OBC is responsible for managing power distribution. To bypass the OBC, use the White wire with a 10-amp inline fuse if the White and Red/White wires are the same gauge. If the Red/White wire is a larger gauge, opt for the Red/White wire on the OBC side of the connector and maintain the fuse. This setup ensures that no power goes to the controller connector when the Tow/Run switch is in the Tow position, mimicking the original OBC functionality. Alternatively, using the Red wire would provide non-fused 48v power at the controller connector. Scroll down and take a look at post #8 for an alternative version.

Regen-2 and Similar Model Years
For Regen-2 and other model years where the Blue wire connects to the harness instead of the controller, the OBC directly powers the electrical system. In this case, follow the same guidelines as for IQ and Excel carts regarding wire choice and fuse usage. This method ensures that the power distribution is safely managed while bypassing the OBC, maintaining the vehicle's functionality without the OBC's power management.

Series Carts
In all model years of Series carts, the OBC provides the negative side of the solenoid using the Yellow wire. To bypass the OBC in Series carts, disconnect the Yellow wire that runs to the OBC and instead run it directly to the controller B- or another negative source like the pack negative. This direct connection effectively removes the OBC from the power distribution loop.

The attached guide can help you determine what drive system your Club Car has

[Michael Eddie]

Discharge Curve: Lithium vs Lead Acid

I wanted to touch base on understanding the differences in the discharge curves between the two battery types. This difference directly impacts how you measure and monitor your battery's state of charge (SoC). In a typical lead acid setup, the battery charge meter is wired to give a voltage based reading of the remaining capacity. This setup works reasonably well for lead acid batteries because their discharge curve is relatively linear. Voltage drops progressively as the battery discharges, allowing the meter to estimate the remaining charge with decent accuracy.

However, this same method does not work effectively with lithium batteries, and here's why. Lithium batteries have a much flatter discharge curve. Unlike lead acid batteries, where voltage steadily decreases as the battery discharges, lithium batteries maintain a higher voltage for a much longer period, only dropping sharply near the end of their discharge cycle. This means that a voltage based meter will give you a false sense of security, showing a high state of charge until the battery is nearly depleted, at which point the voltage will suddenly drop, leaving you stranded without warning.

To accurately read the state of charge of your new lithium setup, you'll need to upgrade to a shunt based state of charge meter

A shunt based meter operates differently from the traditional voltage based meters used with lead acid batteries. Instead of relying solely on voltage readings, a shunt measures the actual current flow in and out of the battery, allowing it to track the exact amount of energy being used and stored. This method gives a much more accurate representation of the remaining capacity of a lithium battery so that you're never caught off guard by a sudden drop in power.

Some high quality lithium golf cart batteries come with their own built in state of charge meters, designed specifically to work with the battery's unique discharge characteristics. However, if your lithium battery doesn’t come with one, installing a shunt based meter is a must. Many people mistakenly believe they can use their existing lead acid battery meter or simply swap in a new voltage based meter, but this will not provide the accurate, reliable readings you need with a lithium setup. I am attaching a chart to this post for a visual representation of the discharge curve for each battery type.

[Bkmac59]

I have a 2022 club car witch has a converter for 16:12.3 106v to 12 2 leads out of it so I’m guessing I have to unhook the 16 lead and just have the 106 for the 48 v lead

Edit: I wanted to share that I was able to find the answer to my question in this post here, thank you to everyone who contributed to the discussion!

[Michael Eddie]

Understanding the Risks of Wiring Multiple Lithium Batteries in Series

I thought it might be worth taking a moment to really talk about a common pitfall some folks run into when upgrading to lithium, the choice to wire multiple smaller lithium batteries in series. After all, most lead acid setups are wired in series, so it seems natural to assume that lithium batteries could work the same way. It’s a tempting option for those making the jump, but there are some important considerations here that often go overlooked.

Individual 6V, 8V, or 12V lithium batteries are often marketed for solar applications and can look like a cost effective option for anyone browsing for an upgrade. It seems like a smart choice. Their prices can be significantly lower than specialized golf cart batteries, and they’re widely available. For many, the savings alone make it a tempting path to lithium power. In light of this, why not make the switch to lithium for less?

But while this setup might seem perfect on paper, these 6v, 8v or even 12v lithium batteries aren’t made for the high demands of golf carts. Each individual lithium battery comes with its own internal Battery Management Systems (BMS) designed to protect them from overcharging, undercharging, overdraw, and overheating. Now, here’s where things get tricky. Each BMS in a series setup is programmed to cut out under certain conditions, and while that works well in the solar world, it doesn’t play out so smoothly in the demanding environment of a golf cart. If even one battery’s BMS trips under load, the entire pack goes down, and with it, your cart’s ability to run. Picture yourself unexpectedly stranded on the course or far from home, waiting to plug in just to reset things, it's a disruption that quickly outweighs any initial savings.

A single 36V or 48V lithium battery is designed to handle the unique power profile of golf carts. With a single, unified BMS calibrated specifically for the demands of driving, this approach not only keeps your system reliable but allows you to enjoy the true benefits of lithium without the frequent interruptions that come from mismatched components. Instead of troubleshooting and restarting separate units, a single pack maintains smooth, steady power throughout your drive. It’s these real world demands and efficiencies that make purpose built lithium golf cart batteries such a valuable investment in the long run.

[aquamusic]

Thanks for your information. Total "Cart Newby" here, with some electrical knowledge. I have acquired a 2003 Club Car, DS Elec IQ 48V Regen (s/n AQ0316-274702). Starting to convert to lithium.

I have a new lithium battery charger and 54V to 12V converter.

Attached is the correct wiring schematic for this model, I hope! The colors do not seem to match your info on bypassing the OBC. Which wires on this schematic need to be joined/severed?

Also the gray wire from OBC (with inline fuse) is not connected to anything. Looks like it should go to the Fuse and Receptacle.

Thanks much.

[Michael Eddie]

Thanks for your information. Total "Cart Newby" here, with some electrical knowledge. I have acquired a 2003 Club Car, DS Elec IQ 48V Regen (s/n AQ0316-274702). Starting to convert to lithium.

I have a new lithium battery charger and 54V to 12V converter.

Attached is the correct wiring schematic for this model, I hope! The colors do not seem to match your info on bypassing the OBC. Which wires on this schematic need to be joined/severed?

Also the gray wire from OBC (with inline fuse) is not connected to anything. Looks like it should go to the Fuse and Receptacle.

Thanks much.

This is a common place where things can get a little tricky as there are actually 2 ways to do this with this setup. To bypass the OBC with your setup you’ll need to jump a few wires. Specifically, you’ll need to join the light blue wire and the white wire together. The light blue wire which comes from the controller needs to get the full 48V power, and the white wire will be coming from the Tow/Run switch. This is important because when the cart is in Tow mode, the white wire will drop to 0V. But, in Run mode, you see the light blue wire receive pack voltage.

Next, find the 10 gauge negative wire and run it directly from the back of the charger receptacle to the pack's negative terminal. This will allow your charger to charge the lithium battery properly even though the OBC is bypassed. Once that’s done, you can disconnect the 6 pin OBC connector and then jump the white and blue wires together on the harness side as described earlier. This will effectively remove the OBC from the charging circuit and allow your lithium setup to function correctly.

[aquamusic]

This is a common place where things can get a little tricky ....

Thanks much! I'm on my way....