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Navigating the world of batteries can be complex, especially when it comes to understanding voltage levels and their implications. Our comprehensive guide to battery voltage charts demystifies this critical aspect of battery technology.
Whether you’re a tech enthusiast, a professional in the field, or simply someone keen to understand the health and efficiency of your batteries, this guide will provide you with essential insights into battery voltage, its measurement, and its significance in various applications.
What Is Battery Voltage?
Battery voltage is a fundamental electrical measure indicating the electric potential difference between two points of a battery. It determines how much electrical force the battery can deliver to a circuit.
Voltage is essentially the pressure from an electrical source that pushes electrons through a conducting loop, enabling them to power a light bulb or spin a motor.
The higher the voltage, the more power the battery can deliver to a device.
| 12V Battery Voltage | State of Charge |
| 12.70 | 100% |
| 12.50 | 90% |
| 12.42 | 80% |
| 12.32 | 70% |
| 12.20 | 60% |
| 12.06 | 50% |
| 11.90 | 40% |
| 11.79 | 30% |
| 11.58 | 20% |
| 11.31 | 10% |
| 10.50 | 0% |
What Is the State of Charge & Discharge?
A battery’s State of Charge (SoC) refers to its current energy level compared to its optimal capacity, expressed as a percentage. It’s like a fuel gauge for batteries, indicating how much charge remains before it needs recharging.
Conversely, the State of Discharge (SoD) measures how much of the battery’s energy has been used. Both are crucial for monitoring battery health and performance.
Understanding SoC and SoD helps in efficiently managing battery usage, ensuring longevity, and preventing over-discharge, which can harm the battery’s lifespan.
Different Types of Batteries & Their Voltages
Lead-Acid
Lead-acid is the oldest form of rechargeable battery chemistry and, for decades, was the traditional choice for consumer applications.
Common in gasoline or diesel-fueled vehicles, lead-acid batteries deliver the large bursts of energy needed for starting engines. While cost-effective, they have a lower energy density and shorter lifespan compared to newer technologies and require regular maintenance to ensure longevity.
Lead-Acid Battery Voltage Chart
| Capacity | 6V Sealed Lead Acid Battery | 6V Flooded Lead Acid Battery |
| 100% | 6.44V | 6.32V |
| 90% | 6.39V | 6.26V |
| 80% | 6.33V | 6.20V |
| 70% | 6.26V | 6.15V |
| 60% | 6.20V | 6.09V |
| 50% | 6.11V | 6.03V |
| 40% | 6.05V | 5.98V |
| 30% | 5.98V | 5.94V |
| 20% | 5.90V | 5.88V |
| 10% | 5.85V | 5.82V |
| 0% | 5.81V | 5.79V |
Lithium-ion
Lithium-ion batteries, popular in modern electronics, stand out for their high energy density and lightweight properties. They’re prevalent in portable devices and electric vehicles, offering longer lifespans and better performance than traditional batteries.
Efficiency and quick charging capabilities make Li-ion batteries a preferred choice for many applications.
Lithium-ion Battery Voltage Chart
| Capacity (%) | 1 Cell | 12 Volt | 24 Volt | 48 Volt |
| 100 | 3.40 | 13.6 | 27.2 | 54.4 |
| 90 | 3.35 | 13.4 | 26.8 | 53.6 |
| 80 | 3.32 | 13.3 | 26.6 | 53.1 |
| 70 | 3.30 | 13.2 | 26.4 | 52.8 |
| 60 | 3.27 | 13.1 | 26.1 | 52.3 |
| 50 | 3.26 | 13.0 | 26.0 | 52.2 |
| 40 | 3.25 | 13.0 | 26.0 | 52.0 |
| 30 | 3.22 | 12.9 | 25.8 | 52.5 |
| 20 | 3.20 | 12.8 | 25.6 | 51.2 |
| 10 | 3.00 | 12.0 | 24.0 | 48.0 |
| 0 | 2.50 | 10.0 | 20.0 | 40.0 |
Deep Cycle
Deep cycle batteries are designed to provide steady power over extended periods.
They improve on traditional lead-acid batteries for situations requiring a consistent energy output, such as in renewable energy systems or recreational vehicles.
Distinguished from traditional flooded lead acid (FLA) batteries, newer valve-regulated lead-acid (VRLA) deep cycle battery technologies like AGM and Gel have a greater depth of discharge. Typically, they have a longer cycle life and require less maintenance than FLA batteries.
Deep Cycle Battery Voltage Chart
| Capacity | 12V | 24V | 48V |
| 100% (charging) | 13.00V | 26.00V | 52.00V |
| 99% | 12.80V | 25.75V | 51.45V |
| 90% | 12.75V | 25.55V | 51.10V |
| 80% | 12.50V | 25.00V | 50.00V |
| 70% | 12.30V | 24.60V | 49.20V |
| 60% | 12.15V | 24.30V | 48.60V |
| 50% | 12.05V | 24.10V | 48.20V |
| 40% | 11.95V | 23.90V | 47.80V |
| 30% | 11.81V | 23.62V | 47.24V |
| 20% | 11.66V | 23.32V | 46.64V |
| 10% | 11.51V | 23.02V | 46.04V |
| 0% | 10.50V | 21.00V | 42.00V |
LiFePO4
Lithium Iron Phosphate (LiFePO4/LFP) batteries offer enhanced safety, faster recharge speeds, and a longer lifespan than standard lithium-ion batteries. T
With an exceptionally long cycle life, high depth of discharge, and a wide range of operating temperatures, LFP batteries are becoming the chemistry of choice in EVs and home backup battery systems like EcoFlow’s DELTA Series.
LiFePO4 batteries are more sustainably and ethically sourced than traditional Li-ion batteries. LFP requires no nickel or cobalt — 70% of which is mined under brutal labor conditions in the DRC.
LiFePO4 Battery Voltage Chart
| Capacity | 12V | 24V | 48V |
| 100% (charging) | 14.6V | 29.2V | 58.4V |
| 100% (resting) | 13.6V | 27.2V | 54.4V |
| 99% | 13.4V | 26.8V | 53.6V |
| 90% | 13.3V | 26.6V | 53.2V |
| 70% | 13.2V | 26.4V | 52.8V |
| 40% | 13.1V | 26.2V | 52.4V |
| 30% | 13.0V | 26.0V | 52.0V |
| 20% | 12.9V | 25.8V | 51.6V |
| 17% | 12.8V | 25.6V | 51.2V |
| 14% | 12.5V | 25.0V | 50.0V |
| 9% | 12.0V | 24.0V | 48.0V |
| 0% | 10.0V | 20.0V | 40.0V |
AGM
AGM (Absorbent Glass Mat) batteries, a subtype of lead-acid batteries, are known for their efficiency and durability. They require minimal maintenance and can handle extreme temperatures better than traditional lead-acid batteries. AGM batteries are commonly used in backup power systems and off-grid applications for their reliable performance and long service life.
AGM Battery Voltage Chart
| Capacity | 12V | 24V | 48V |
| 100% (charging) | 13.0V | 26.00V | 52.00V |
| 100% (resting) | 12.85V | 25.85V | 51.70V |
| 99% | 12.80V | 25.75V | 51.45V |
| 90% | 12.75V | 25.55V | 51.10V |
| 80% | 12.50V | 25.00V | 50.00V |
| 70% | 12.30V | 24.60V | 49.20V |
| 60% | 12.15V | 24.30V | 48.60V |
| 50% | 12.05V | 24.10V | 48.20V |
| 40% | 11.95V | 23.90V | 47.80V |
| 30% | 11.81V | 23.62V | 47.24V |
| 20% | 11.66V | 23.32V | 46.64V |
| 10% | 11.51V | 23.02V | 46.04V |
| 0% | 10.50V | 21.00V | 42.00V |
Frequently Asked Questions
Symptoms of a low-voltage battery in a vehicle include dimming headlights, slow engine cranking, and the inability to start your vehicle or power devices. Electronic malfunctions and frequent need for jump-starts are also telltale signs. Regularly experiencing these issues in your vehicle indicates a battery struggling to maintain its voltage.
A battery is generally considered “bad” or damaged when its output voltage drops below a critical threshold. For a 12V battery, a voltage below 10.5V under load is typically a sign that it has outlived its cycle life. Consistently low voltage readings often signal it’s time for a replacement.
Final Thoughts
Battery voltages can be complex, but understanding the essentials helps you make informed choices for your power needs.
From the diverse types of battery chemistries to recognizing the symptoms of decreased performance, this guide offers insights into the intricate dynamics of battery health.
For those seeking reliable, innovative power solutions, explore EcoFlow’s range of portable power stations.
Whether for off-grid outdoor adventures or as a dependable home backup, EcoFlow’s technology ensures you’re always powered up.
Discover more about EcoFlow’s Portable Power Stations.