72V batteries are high-voltage energy storage systems with a nominal voltage of 72 volts, optimized for electric vehicles (EVs) requiring sustained power and extended range. They utilize lithium-ion chemistries like LiFePO4 or NMC for higher energy density and thermal stability, making them ideal for golf carts, e-scooters, and heavy-duty EVs. Charging typically follows a CC-CV protocol with termination at 84V (for LiFePO4) to maximize cycle life.
What Are the Best 12V LiFePO4 Batteries with Built-in BMS in 2025?
What defines the core components of a 72V battery?
A 72V battery system combines series-connected cells, a Battery Management System (BMS), and thermal controls. Lithium-ion cells (LiFePO4 or NMC) are arranged in 24S configurations to reach 72V nominal. The BMS ensures voltage balancing, while cooling systems prevent overheating during high-current discharge cycles common in EVs.
Deep Dive: A 72V LiFePO4 pack typically uses 24 cells in series (3.2V each), achieving 76.8V fully charged. The BMS monitors cell-level voltages and temperatures, shutting down the pack if thresholds exceed 4.2V (NMC) or 3.65V (LiFePO4). Pro Tip: Opt for modular designs—replacing a single faulty cell is cheaper than discarding the entire pack. For example, a 72V 50Ah e-scooter battery can deliver 150A continuous current, enabling uphill climbs without voltage sag. However, mismatched cells can reduce capacity by 15–20% over 500 cycles.
How does 72V compare to 48V or 96V systems?
72V systems balance power density and cost-efficiency, outperforming 48V in torque and range while avoiding 96V’s complex safety requirements. They’re ideal for mid-sized EVs needing 50–100 km range at 45–60 km/h speeds.
Deep Dive: Doubling voltage from 48V to 72V cuts current by half for the same power, reducing copper losses and wire thickness. But what happens if you push to 96V? While efficiency improves further, insulation costs spike, and motors require rewinding. Pro Tip: For DIY projects, stick with 72V—controllers and chargers are widely available. Take electric dirt bikes: 72V models achieve 70 km/h with 65 km range, whereas 48V versions struggle beyond 50 km/h.
| Voltage | Typical Range | Ideal Use Case |
|---|---|---|
| 48V | 30–50 km | Light e-bikes |
| 72V | 50–110 km | E-scooters, cargo EVs |
| 96V | 80–150 km | High-performance EVs |
Why choose LiFePO4 over NMC for 72V batteries?
LiFePO4 offers safety and longevity (3,000–5,000 cycles) vs. NMC’s higher energy density but shorter lifespan (1,200–2,000 cycles). LiFePO4’s stable chemistry minimizes thermal runaway risks, crucial for passenger-carrying EVs.
Deep Dive: While NMC packs achieve 200–250 Wh/kg versus LiFePO4’s 120–160 Wh/kg, the latter tolerates overcharging up to 4.2V/cell without combustion. Practically speaking, delivery fleets prefer LiFePO4 for daily deep cycling, whereas racing EVs use NMC for weight savings. Pro Tip: Use NMC only with advanced cooling—cells degrade rapidly above 45°C. For example, a 72V 30Ah NMC pack weighs 9 kg vs. 14 kg for LiFePO4, but lasts half as many cycles.
What Is the Full Charge Voltage of a 12V LiFePO4 Battery?
What charging protocols suit 72V batteries?
72V batteries use CC-CV charging with voltage cutoffs tailored to chemistry. LiFePO4 charges to 87.6V (3.65V/cell), while NMC stops at 100.8V (4.2V/cell). Smart chargers adjust rates based on temperature and SOC.
Deep Dive: Charging starts with constant current (e.g., 0.5C) until reaching 80% SOC, then switches to constant voltage to prevent cell stress. But how do you avoid imbalance? High-quality BMS modules redistribute energy during CV phase. Pro Tip: For fast charging, limit to 1C—a 100Ah pack charges in 1 hour, but heat rises by 8–10°C. For example, a 72V golf cart battery charges fully in 4–5 hours using a 15A charger.
| Chemistry | Max Charge Voltage | Cycle Life |
|---|---|---|
| LiFePO4 | 87.6V | 3,000+ |
| NMC | 100.8V | 1,200–2,000 |
Redway Battery Expert Insight
FAQs
Yes, but they require a 72V-to-48V DC converter. Direct use is inefficient—most solar inverters max out at 48V input.
How long does a 72V LiFePO4 battery last?
3,000–5,000 cycles (8–12 years) at 80% depth of discharge. Storage below -20°C reduces lifespan by 40%.
