Can I put three 12-volt batteries in a 36 volt golf cart?
Yes, three 12V batteries wired in series can technically create a 36V system for a golf cart. However, standard 36V carts use six 6V batteries for higher capacity and longevity. Using 12V units reduces runtime by ~50% due to lower amp-hour (Ah) ratings and may void warranties. Always verify physical fit, terminal alignment, and BMS compatibility before switching configurations.
Is voltage the only factor when using 12V batteries in a 36V cart?
No—capacity (Ah) and cycle life are equally critical. Most 12V golf cart batteries have 80–120Ah ratings versus 180–225Ah in 6V deep-cycle models. This halves usable energy (3.6kWh vs 7.2kWh), reducing range by 40–60%. Pro Tip: Use a lithium upgrade (e.g., 36V 100Ah LiFePO4) for triple the cycles and 70% weight savings.
While voltage matches when three 12V batteries are series-linked, their lower energy density forces frequent recharges. For example, Trojan T-1275 12V batteries (150Ah) provide 5.4kWh in a 36V setup, whereas six T-105 6V batteries (225Ah) deliver 8.1kWh—50% more per charge. Mechanical compatibility also matters: 12V units are taller (10–12” vs 8–9”), potentially interfering with seat brackets. Always measure tray dimensions and terminal positions. Transitioning? Lithium batteries solve space issues but require voltage-specific chargers.
| Parameter | 3x12V Lead-Acid | 6x6V Lead-Acid |
|---|---|---|
| Total Voltage | 36V | 36V |
| Typical Capacity | 100–150Ah | 180–225Ah |
| Energy (kWh) | 3.6–5.4 | 6.5–8.1 |
How does battery chemistry affect performance?
Lead-acid and lithium-ion behave differently under load. Three 12V AGM batteries discharge at 80% efficiency versus 90% for lithium, wasting more energy as heat. They also sag below 10.5V under hill climbs, triggering low-voltage cutoffs. Pro Tip: Lithium maintains stable voltage, delivering consistent torque even at 20% charge.
Lead-acid batteries suffer from the “Peukert effect”—losing 20–40% capacity at high currents. A 36V cart pulling 100A will only get 70Ah from a 100Ah lead-acid pack versus 95Ah from lithium. Real-world example: Climbing a 15% grade for 10 minutes drains three 12V AGM batteries to 50%, while lithium stays above 80%. Transitionally, lithium’s flat discharge curve (36V to 30V) prevents motor power drop-offs. But remember: Mixing chemistries in series causes imbalance—never combine lead-acid and lithium in the same pack.
Fasta Power Expert Insight
FAQs
No—mixed voltages create imbalance, overcharging some batteries while undercharging others. This risks fires and permanent capacity loss.
How long will three 12V batteries last in a 36V cart?
If deep-cycle, expect 1–2 years with daily use versus 4–6 years for lithium. Shallow discharges (≤50%) can extend lead-acid lifespan by 30%.