When it comes to powering high-performance RC drones, planes, and cars, 4S LiPo batteries stand out as a favorite among enthusiasts. These compact powerhouses deliver impressive voltage and capacity combinations that can transform how your RC machine performs.
Understanding the key specifications — especially voltage and capacity — isn’t just about technical knowledge; it’s about optimizing performance, extending battery life, and ensuring safety. Whether you’re new to LiPo technology or an experienced RC hobbyist, knowing what makes a 4S LiPo tick is essential to unlocking its full potential.
What Does 4S Mean in a LiPo Battery?
Before diving into numbers, let’s decode what “4S” means.
A 4S LiPo battery is made up of four individual cells connected in series. Each LiPo cell typically delivers:
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3.7V nominal voltage (average voltage during use)
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4.2V fully charged voltage
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3.0V minimum safe voltage
When these cells are connected in series, their voltages add up:
3.7V × 4 = 14.8V nominal voltage
4.2V × 4 = 16.8V fully charged
3.0V × 4 = 12.0V minimum safe discharge
This configuration gives the 4S battery its characteristic high voltage, which means more speed, torque, and overall efficiency for your RC setup.
Voltage Explained: The Power Pulse Behind 4S LiPo Batteries
Voltage determines how much electrical potential your battery can supply. In simple terms, it dictates how fast your motors spin and how much thrust your system can generate.
A 4S LiPo’s nominal voltage of 14.8V makes it more powerful than 3S (11.1V) packs while remaining compact enough for most RC applications.
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Fully Charged Voltage: 16.8V
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Nominal Voltage: 14.8V
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Minimum Safe Voltage: 12V
Why Voltage Matters:
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Higher voltage = more speed and power for RC vehicles.
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However, over-voltage can stress motors and ESCs if they aren’t rated for 4S.
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Low voltage (below 3.0V per cell) can damage or permanently degrade LiPo cells.
Pro Tip: Always use a balance charger to ensure all four cells charge evenly — this prevents cell imbalance, swelling, and voltage drift over time.
Capacity Demystified: Understanding mAh
Capacity, measured in milliamp-hours (mAh), determines how long your battery can supply current.
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A 1300mAh 4S LiPo is lightweight and perfect for racing drones that need quick bursts of power.
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A 5000mAh 4S LiPo offers longer runtime, ideal for RC cars or planes that prioritize endurance.
To understand capacity better:
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Higher mAh = longer runtime but adds extra weight.
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Lower mAh = lighter setup but shorter operation time.
Example Calculation:
A 4S 5000mAh (5Ah) battery rated at 25C can discharge:
5Ah × 25C = 125A of continuous current.
This means the battery can safely supply 125 amps to the motor — enough for most high-performance RC setups.
Voltage vs. Capacity: Finding the Perfect Balance
Both voltage and capacity work together to define how your RC system performs:
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Voltage affects speed and power output.
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Capacity affects runtime and endurance.
For instance:
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A 4S 1300mAh pack is excellent for FPV drones where agility matters more than flight duration.
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A 4S 5000mAh pack suits RC trucks or airplanes that demand longer operation times.
Choosing the right balance is key — too much capacity adds weight, while too little voltage limits performance.
Pro Insight: Match the battery specs to your motor and ESC ratings to ensure optimal efficiency without overloading the system.
C Rating: The Secret Behind Discharge Power
The C rating indicates how quickly a LiPo battery can safely discharge energy. It’s a multiplier of capacity that defines the maximum current output.
For example:
A 4S 2200mAh 30C battery can deliver:
2.2Ah × 30C = 66A continuous discharge.
A higher C rating means the battery can supply more current without overheating or losing voltage stability.
Choosing the Right C Rating:
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FPV drones: 60C–100C for fast bursts.
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RC cars: 40C–75C for sustained power.
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RC planes: 30C–50C for smooth discharge curves.
Tip: Always select a C rating slightly higher than your motor’s current demand to prevent stress and heat buildup.
Matching Specs to Real-World Applications
Different applications require different power profiles:
For FPV Drones:
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Prefer lightweight 4S packs (1300–1800mAh, 75C+).
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Prioritize high discharge rate for quick response and acceleration.
For RC Cars:
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Opt for higher capacity batteries (4000–6000mAh).
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Medium to high discharge rating (50C+) for consistent torque delivery.
For RC Airplanes:
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Aim for a balance: 2200–3500mAh, 40C range for smooth, long-duration flights.
How to Read 4S LiPo Labels Like a Pro
Let’s decode an example battery label:
“4S 5000mAh 50C 14.8V LiPo”
| Spec | Meaning |
|---|---|
| 4S | 4 cells in series |
| 5000mAh | Battery capacity |
| 50C | Discharge rate |
| 14.8V | Nominal voltage |
When shopping, verify that all these specs align with your device’s motor, ESC, and charger requirements.
Safety First: Handling 4S LiPo Batteries Responsibly
LiPo batteries are powerful but must be handled carefully.
Charging Tips:
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Always use a LiPo balance charger.
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Never exceed 4.2V per cell.
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Avoid fast-charging beyond manufacturer recommendations.
Storage Guidelines:
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Store at 3.8V per cell (15.2V total).
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Keep in a fireproof LiPo bag or metal box.
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Avoid extreme heat or cold.
Warning Signs of Damage:
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Swelling (puffing)
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Excessive heat
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Cell imbalance or rapid voltage drop
If you notice any of these, stop using the battery immediately and recycle it responsibly.
Common Misconceptions About 4S LiPo Batteries
🚫 Myth 1: Higher voltage always means better performance.
✅ Reality: Only if your system is rated for it. Otherwise, it may cause overheating or component damage.
🚫 Myth 2: Any charger can charge a LiPo battery.
✅ Reality: Only use LiPo-specific balance chargers for safe and even charging.
🚫 Myth 3: Capacity only affects runtime.
✅ Reality: Capacity also influences discharge rates, battery stress, and flight balance.
Choosing the Right 4S LiPo for Your Needs
| Application | Recommended Capacity | C Rating | Nominal Voltage |
|---|---|---|---|
| FPV Drones | 1300–1800mAh | 75C | 14.8V |
| RC Cars | 4000–6000mAh | 50C | 14.8V |
| RC Planes | 2200–3500mAh | 40C | 14.8V |
Match your choice to the motor draw, flight style, and weight capacity for best results.
Conclusion: Mastering the Power of 4S LiPo Batteries
Understanding voltage and capacity specs of 4S LiPo batteries helps you make smarter choices that directly affect performance, safety, and longevity.
The voltage (14.8V nominal) gives your motors the energy they need, while the capacity (mAh) dictates how long you can enjoy your flight or drive. Combined with the right C rating and charging practices, you can ensure maximum power delivery and reliability every time.
In short — know your specs, treat your battery well, and your RC performance will soar.
FAQs
1. What is the nominal voltage of a 4S LiPo battery?
A 4S LiPo has a nominal voltage of 14.8V (3.7V × 4 cells).
2. How much voltage does a fully charged 4S LiPo have?
A fully charged 4S LiPo battery reaches 16.8V (4.2V per cell × 4).
3. Can I use a 4S LiPo instead of a 3S?
Yes, but only if your ESC and motor support higher voltage. Otherwise, you risk damaging your electronics.
4. How long will a 4S 5000mAh battery last?
Runtime ≈ (Battery Capacity ÷ Current Draw) × 60.
For example: 5000mAh ÷ 25A ≈ 12 minutes of operation.
5. What happens if a LiPo battery is over-discharged?
Dropping below 3.0V per cell can cause permanent damage, swelling, or complete failure.
6. What’s the best C rating for a 4S LiPo?
For most RC drones and cars, 40C to 75C offers a good balance between performance and safety.
7. How should I store a 4S LiPo battery?
Store at 3.8V per cell (15.2V total) in a cool, dry place inside a fireproof container.
