Battery Energy Density Chart
Compare the weight and volume energy density of every major battery chemistry. Understand why LiFePO4, NMC, and lead-acid differ — and which matters for your application.
Energy Density by Chemistry
The table below compares gravimetric (Wh/kg) and volumetric (Wh/L) energy density for common battery chemistries, along with the typical weight of a 12V 100Ah pack of each type.
| Chemistry | Gravimetric (Wh/kg) | Volumetric (Wh/L) | Typical Weight (12V 100Ah) | Notes |
|---|---|---|---|---|
| LiFePO4 | 90–160 | 200–350 | 10–14 kg | Best cycle life, safest lithium |
| NMC | 150–260 | 400–700 | 8–12 kg | Highest density, EV standard |
| NCA | 200–260 | 500–650 | 8–12 kg | Used in Tesla, high energy |
| Lead-Acid Flooded | 25–40 | 60–110 | 28–35 kg | Cheapest, heaviest, oldest |
| AGM | 30–45 | 70–120 | 25–32 kg | Maintenance-free lead-acid |
| Gel | 30–40 | 60–110 | 26–33 kg | Deep-cycle optimized, sealed |
Ranges represent typical commercial cells. Values vary by manufacturer, cell format (prismatic, pouch, cylindrical), and BMS weight.
Gravimetric vs Volumetric Density
Gravimetric energy density (Wh/kg) tells you how much energy you get per kilogram. This is the critical metric when weight matters — in EVs, drones, portable devices, and boats where displacement is a concern.
Volumetric energy density (Wh/L) tells you how much energy you get per liter of space. This is critical when space is constrained — in tight engine bays, under seats, in wall-mounted enclosures, or inside compact battery cabinets.
Weight Priority
Choose NMC or NCA when weight is the primary constraint. At 200+ Wh/kg, these chemistries deliver nearly 5–6× the energy per kilogram compared to lead-acid. Ideal for EVs, drones, and weight-sensitive marine applications.
Volume Priority
Choose NMC or LiFePO4 prismatic cells when space is tight. NMC offers 400–700 Wh/L, making it the most compact option. LiFePO4 prismatic cells are larger but compensate with longer cycle life and safety.
Practical Weight Comparison
The table below compares the actual weight and approximate volume of a 12V 100Ah (1,200Wh) battery pack for each chemistry. This is the most direct way to see the real-world impact of energy density differences.
| Chemistry | Pack Weight | Approx. Volume | Cost Range | Cycle Life |
|---|---|---|---|---|
| LiFePO4 | 10–14 kg | ~13–15 L | $400–$800 | 3,000–10,000 |
| NMC | 8–12 kg | ~5–8 L | $500–$1,000 | 1,000–2,000 |
| Lead-Acid Flooded | 28–35 kg | ~18–25 L | $100–$200 | 300–500 |
| AGM | 25–32 kg | ~16–22 L | $200–$400 | 400–800 |
| Gel | 26–33 kg | ~17–23 L | $250–$450 | 500–1,000 |
Cost ranges are approximate and vary by region, brand, and purchase volume. Cycle life assumes 80% depth-of-discharge.
Why Energy Density Matters
Energy density directly impacts system design, cost, and performance. The right chemistry depends on whether weight, space, or budget is your primary constraint.
RV & Camper
Weight impacts fuel economy and payload. A 400Ah LiFePO4 bank weighs ~50kg vs ~130kg for lead-acid. The 80kg savings means more gear, better mileage, and less wear on suspension. Space savings allow mounting in tighter compartments.
Marine
Every kilogram above the waterline affects vessel stability and handling. High-density batteries low in the hull keep center of gravity down. Lighter batteries also mean faster acceleration and better fuel economy for powerboats.
Electric Vehicles
Energy density determines range per kilogram of battery. A 75kWh NMC pack at 160kg gives 500km range. The same energy in lead-acid would weigh over 2,000kg — making the vehicle impractical. EV viability depends entirely on gravimetric density.
Try It
Use the Battery Pack Calculator to design a pack with the right chemistry, configuration, and total energy for your application.
Open Battery Pack CalculatorFrequently Asked Questions
What is the difference between gravimetric and volumetric energy density?
Gravimetric energy density (Wh/kg) measures how much energy a battery stores per unit of weight. Volumetric energy density (Wh/L) measures how much energy it stores per unit of volume. A battery with high gravimetric density is lightweight; one with high volumetric density is compact. LiFePO4 has moderate gravimetric density but lower volumetric density than NMC.
Why is LiFePO4 heavier than NMC for the same capacity?
LiFePO4 uses an iron-phosphate cathode, which is heavier per unit of stored energy compared to the nickel-manganese-cobalt (NMC) cathode. However, LiFePO4 offers significantly longer cycle life (3,000–10,000 cycles vs. 1,000–2,000 for NMC), better thermal stability, and no cobalt content — making it the preferred choice for stationary storage despite the weight penalty.
How does energy density affect RV and marine applications?
Weight and space are at a premium in RVs and boats. Higher energy density means more usable energy in less weight and volume. A 100Ah LiFePO4 battery at ~13kg replaces a 100Ah lead-acid at ~30kg — saving 17kg per battery. In a 4-battery bank, that is nearly 70kg of weight savings, which directly improves fuel efficiency and cargo capacity.
What is the energy density of the latest solid-state batteries?
Solid-state batteries are projected to achieve 400–500 Wh/kg gravimetrically, roughly double current lithium-ion cells. However, they remain in development or early commercial stages as of 2025. Current production batteries top out around 260 Wh/kg (NMC) for consumer applications and 160 Wh/kg (LiFePO4) for commercial/industrial cells.