A LiFePO4 cell is 3.2 V nominal, charges to at most 3.65 V and is cut off at 2.5 V. That puts a 12.8 V (4S) pack at 10.0–14.6 V, a 25.6 V (8S) pack at 20.0–29.2 V and a 51.2 V (16S) pack at 40.0–58.4 V. Between roughly 30% and 90% charge the resting voltage barely moves, so a voltage chart gives a rough estimate, not an exact reading.

Key Takeaways

• EVE Energy’s LF105 specification lists a 3.2 V nominal cell with 3.65 V and 2.5 V charge and discharge cut-offs, and Battery University gives the same 2.5–3.65 V operating range.
• Pack voltage is the number of cells in series times the cell voltage, so a “48 V” LiFePO4 pack can be 15S (37.5–54.75 V) or 16S (40.0–58.4 V).
• The discharge curve is very flat, so voltage mainly shows “full” and “low”, according to Battery University.
• Measure resting voltage with loads and chargers disconnected, and confirm the middle of the range with a BMS or battery monitor.
• OEM buyers should ask for the cell datasheet, the series cell count and the BMS voltage thresholds, not just a “12V” or “48V” label.

What is the voltage of a single LiFePO4 cell?

A LiFePO4 cell has a nominal voltage of 3.2 V, a maximum charge voltage of 3.65 V and a discharge cut-off of 2.5 V. Battery University lists the nominal cell voltage as 3.20 V or 3.30 V with a typical operating range of 2.5–3.65 V.

The EVE Energy LF105 product specification (3.2 V, 105 Ah prismatic cell, version F) shows how one manufacturer states these limits:

• Nominal voltage: 3.2 V.
• Charge cut-off: 3.65 V. The standard charge is constant current to 3.65 V, then a hold at that voltage until the current falls below 0.05C.
• Discharge cut-off: 2.5 V at 25°C. The same document runs its −20°C discharge test to 2.0 V.
• Temperature windows: charge at 0–55°C and discharge at −20–55°C.
• Recommended SOC window: 10%–90%.

These are one maker’s limits for one cell. Other cells differ, so read the datasheet of the cell inside your pack.

What is the LiFePO4 voltage chart for 12V, 24V and 48V packs?

A LiFePO4 pack sits at roughly 3.3 V per cell for most of its charge, so a 12.8 V pack rests near 13.0–13.3 V through the middle of its range. The table below multiplies the per-cell bands by 4, 8 and 16 cells.

Only the maximum charge and discharge cut-off rows come from a datasheet (the EVE LF105 limits above). The resting rows are rounded planning bands, not Jetray test data. No standard publishes one universal LiFePO4 SOC table, and cells from different makers differ by a few hundredths of a volt.

Treat the charge percentages as rough bands. Use the table to spot a battery that is clearly full, clearly low or clearly out of range, not to read 55% versus 65%.

How do cell count and pack voltage match up?

Pack voltage equals the number of series cells times the cell voltage, so the same label can hide different cell counts. The table applies the 3.2 V nominal, 3.65 V maximum and 2.5 V cut-off to common series counts.

The “12 V” and “12.8 V” names refer to the same 4S pack: 12 V is the common shorthand and 12.8 V is the LiFePO4 nominal value (4 × 3.2 V). A chart or charger built for a 15S “48 V” pack will not match a 16S pack, so confirm the series count first.

For more on how a single cell fits into a pack, see Jetray’s 3.2V battery guide. For a wider voltage reference that also covers lead-acid, see the battery voltage and SOC chart guide.

What are the charging, float and cut-off voltages?

Charge a LiFePO4 pack to no more than 3.65 V per cell, which is 14.6 V on 4S, 29.2 V on 8S and 58.4 V on 16S. The exact setpoints should come from the battery maker.

• Absorption (constant voltage): many system designers set it a little below the maximum to leave margin. The correct value depends on the cell and the BMS.
• End of charge: the EVE specification ends its standard charge when current falls below 0.05C at 3.65 V.
• Float: the same specification does not describe a continuous float. Follow the battery maker’s float guidance, or ask the supplier before enabling it.
• Low-voltage cut-off: 2.5 V per cell at normal temperature (10.0 V on 4S). Systems often disconnect earlier to protect the cells.
• Cold charging: the EVE specification lists a 0°C lower charge limit, and Battery University warns that charging lithium-ion below freezing can plate metallic lithium and cause permanent damage.

For charger stages in more detail, see Jetray’s battery charging guide.

How do you measure LiFePO4 voltage correctly?

Measure the resting voltage with every load and charger disconnected, then compare it with the bands in the table. Follow these steps:

1. Disconnect loads and chargers. Inverters, DC-DC chargers and monitors all pull current and distort the reading.
2. Let the battery rest. Battery University says a battery must rest in the open-circuit state for at least four hours before its voltage is a reliable charge reference. A shorter rest gives a rough reading only.
3. Measure at the battery terminals. Use a multimeter on DC volts. Long cables and fuses add voltage drop if you measure elsewhere.
4. Note the temperature. Battery University notes that heat raises the voltage reading and cold lowers it.
5. Compare with the datasheet. Use the maker’s curve or thresholds first and a generic table second.

Why is voltage a poor state-of-charge gauge for LiFePO4?

Voltage is a poor gauge because the LiFePO4 discharge curve is very flat. Battery University says voltage “only indicates full charge and low charge” for lithium iron phosphate and similar chemistries, so the middle of the range cannot be read accurately.

• Flat curve: a few tens of millivolts per cell cover a large share of the capacity.
• Load: voltage sags under load and recovers when the load stops, so a loaded reading looks lower than the true charge level.
• Temperature: the same charge level reads differently when the cell is hot or cold.
• Cell balance: pack voltage is a sum. Battery University notes that LFP self-discharge can unbalance cells as a battery ages, so one weak cell can trigger protection while the pack total looks normal.

Current counting works better. Battery University says coulomb counting “works well, especially with Li-ion”, although it still needs periodic calibration. A BMS or battery monitor that counts current in and out, and uses voltage only to correct at full and empty, gives a steadier reading.

Can you use a lead-acid voltage chart for LiFePO4?

No, a lead-acid voltage chart does not fit LiFePO4. The two chemistries have different nominal voltages, different charge and cut-off limits and different curve shapes, so a lead-acid table will misread the charge level and can lead to wrong charger or low-voltage disconnect settings.

Use a LiFePO4-specific table, such as the one above, or the cell maker’s curve. Keep any lead-acid reference separate.

What should OEM buyers check?

OEM buyers should check how a pack’s voltage window, BMS thresholds and state-of-charge reporting are defined before they design a charger or display around it. Ask the supplier for:

• Cell datasheet: nominal voltage, charge and discharge cut-offs, temperature windows and any recommended SOC window.
• Series cell count: the “S” number sets the whole voltage range (see the cell count table).
• BMS thresholds: over-voltage, under-voltage and recovery points, per cell and for the pack, plus the low-temperature charge limit.
• SOC method: whether the reported charge level comes from current counting, voltage or both, and how it is recalibrated.
• Charger and inverter profile: the charge voltage and low-voltage disconnect your equipment must match.
• Documents: copies of the test reports and certificates for your specific model, with scope and validity dates.

How does Jetray approach this?

Jetray lists a voltage window on its LiFePO4 product pages, and those windows follow the cell-count math above. The figures below are as listed on each page, not independent measurements.

• 12V 100Ah LiFePO4 Lithium Battery: Jetray lists a 12.8 V nominal voltage, a 10–14.6 V operating voltage and charging at 0–45°C.
• 48V 100Ah LiFePO4 Lithium Battery: Jetray lists a 37.5–54.75 V operating range. That matches 15 cells at 2.5–3.65 V, though the page does not state the cell count.

For custom packs, Jetray’s Customized Service page lists BMS design that controls charge and discharge and reports SOH and SOC, with real-time operating data available, plus CAN, RS485, Bluetooth and WiFi communication options. Jetray also lists LiFePO4 packs from 12V to 72V in its LiFePO4 battery pack range.

Sources and data checked in October 2026: EVE Energy LF105 product specification (version F, 2019-12-02, third-party hosted copy), Battery University BU-205 (Types of Lithium-ion), BU-903 (How to Measure State-of-charge) and BU-410 (Charging at High and Low Temperatures). Resting-voltage bands are rounded planning values, not test data.