Can You Use Three 12V Batteries in a 36V Golf Cart

A 36V golf cart system relies on batteries connected in series to deliver sufficient power. Typically, six 6V batteries are used, but three 12V deep-cycle batteries can also achieve 36V when wired in series. The system’s voltage depends on the sum of individual batteries, while capacity (Ah) determines runtime. Proper wiring and compatible batteries are critical for performance and safety.

36V 100Ah LiFePO4 Golf Cart Battery

What Are the Key Differences Between 6V and 12V Golf Cart Batteries?

6V batteries generally offer higher amp-hour (Ah) capacity and longer runtime compared to 12V batteries. Three 12V batteries provide 36V but lower total Ah, reducing range. Conversely, six 6V batteries maintain higher Ah, optimizing endurance. Physical size and weight also differ: 12V batteries are larger per unit but reduce total battery count, potentially simplifying installation.

When comparing 6V and 12V batteries, energy density and design purpose matter significantly. A Trojan T-105 6V battery delivers ~225Ah, while three 100Ah 12V units total just 100Ah in a 36V configuration. This capacity gap directly impacts operating time between charges. Thicker plates in 6V batteries enhance durability for deep discharges, whereas 12V models often use thinner plates optimized for shorter cycles. Spatially, six 6V batteries distribute weight more evenly but require more installation space. Cost per Ah also favors 6V batteries for heavy use despite higher upfront quantity.

Why Might Using Three 12V Batteries Affect Performance?

Using three 12V batteries in a 36V system may reduce runtime due to lower total Ah capacity. For example, three 100Ah 12V batteries yield 36V/100Ah, while six 220Ah 6V batteries produce 36V/220Ah. Additionally, 12V batteries not designed for deep cycling may degrade faster under frequent discharges, shortening lifespan and increasing long-term costs.

How to Safely Wire Three 12V Batteries in a 36V System

1. Connect the positive terminal of Battery 1 to the negative terminal of Battery 2.
2. Link the positive terminal of Battery 2 to the negative terminal of Battery 3.
3. Use the remaining positive (Battery 3) and negative (Battery 1) terminals as the system’s output.
4. Verify connections with a multimeter to ensure 36V total.

What Are the Long-Term Maintenance Implications?

12V batteries require regular watering (if flooded), terminal cleaning, and equalization charging. Improper maintenance accelerates sulfation, reducing efficiency. Ensure the charger matches the battery type (AGM, flooded, gel) to prevent overcharging. Monthly voltage checks and avoiding full discharges below 50% can prolong lifespan.

Maintenance intensity increases with 12V batteries due to their lower tolerance for deep cycles. Flooded models need monthly electrolyte checks—add distilled water when levels drop ¼” below plate tops. For terminals, scrub corrosion quarterly using a baking soda solution and apply anti-oxidant spray. Equalize every 60-90 days by charging at 15.5-16.3V for 2-3 hours, but skip this for AGM/gel batteries. Temperature extremes compound wear: capacity drops 1% per 1°F below 80°F. Always store carts in climate-controlled spaces when possible.

Expert Views

“While three 12V batteries can work, they’re rarely ideal for golf carts. At Redway, we recommend sticking with 6V batteries for higher Ah and durability. If using 12V models, prioritize deep-cycle variants and monitor performance closely to avoid premature failure.” — Redway Power Systems Engineer

Conclusion

Using three 12V deep-cycle batteries in a 36V golf cart is technically feasible but compromises runtime and longevity. For occasional use, this setup may suffice, but frequent riders should opt for six 6V batteries. Always consult manufacturer guidelines and prioritize batteries specifically designed for deep cycling.

FAQ

Q: Can I mix 12V and 6V batteries in my golf cart?

A: No. Mixing voltages disrupts the system, causing uneven charging and potential damage.

Q: How long will three 12V batteries last on a single charge?

A: Runtime depends on Ah capacity and load. A 100Ah pack typically lasts 1.5–2 hours under moderate use.

Q: Are lithium batteries a better alternative for 36V systems?

A: Yes. Lithium batteries offer higher Ah, lighter weight, and longer lifespans but at a higher upfront cost.