How Long to Charge a Medium Racing Drone Battery (5S, 4,000 mAh)?
Charging a Medium Racing Drone Battery (5S, 4,000 mAh) from empty to full takes about 1 h 10 min with its standard 90W charger. The battery holds roughly 74 Wh, and this page estimates the time for every common charger wattage, using the Lithium-ion (Li-ion / Li-Po) chemistry it actually uses.
Charge time calculator for Medium Racing Drone Battery (5S, 4,000 mAh)
Estimated charge time
1 h 10 min
Includes the slower li-ion taper phase above 80%.
Charge time by charger wattage
| Charger | Power | Full charge (0-100%) |
|---|---|---|
| Slow charger | 45W | 2 h 19 min |
| Standard charger | 90W | 1 h 10 min |
| Fast charger | 140W | 45 min |
| Ultra-fast charger | 180W | 35 min |
Battery capacity: 74 Wh · Chemistry: li-ion
The Medium Racing Drone Battery represents a carefully calibrated balance between endurance and agility—the sweet spot for pilots who demand consistent flight times without sacrificing the snappy throttle response essential to competitive racing. Li-ion chemistry delivers the stable voltage curve that racing applications require, ensuring your drone maintains predictable handling characteristics throughout the flight window rather than experiencing the voltage sag that can compromise precision maneuvers during tight gate passes or high-speed pursuits. This makes the 5S configuration particularly popular among intermediate to advanced racers who've learned that a battery's personality matters as much as its capacity.
Proper charging habits directly influence both performance longevity and safety with this battery type. Li-ion cells thrive on regular, moderate charging cycles—avoiding complete depletion before recharging, and resisting the temptation to "top off" before every single flight, helps preserve the chemistry's natural lifespan. When not flying, store the battery in a cool, dry location at a partial charge state rather than fully depleted or fully topped; this simple practice reduces stress on the cells during downtime between racing seasons or extended storage periods. Always inspect the battery's connectors and casing before and after flights, as any sign of puffing, corrosion, or heat damage warrants immediate retirement of the pack.
With the fastest charger listed here (Ultra-fast charger, 180W) it takes about 35 min. With the slowest (Slow charger, 45W) it takes about 2 h 19 min. Mid-range racing battery balancing flight duration with responsive power delivery for competitive racing.
Frequently asked questions
- How long does it take to charge a Medium Racing Drone Battery (5S, 4,000 mAh)?
- From 0% to 100% with the standard 90W charger, it takes about 1 h 10 min. Using a faster charger shortens that; using a weaker one extends it, see the table above for exact numbers.
- Why does my racing drone feel less responsive toward the end of a flight with this battery?
- Even high-quality li-ion cells experience some voltage sag under the aggressive current demands of racing—rapid acceleration, tight turns, and sustained high throttle draw the battery harder than recreational flying. This is normal and expected behavior; it's simply the battery's chemistry responding to the electrical load. Knowing your battery's voltage curve allows you to land with a safe margin before performance degradation becomes dangerous, and swapping to a fresh pack ensures each race run starts with peak power delivery.
- How should I handle charging if I'm doing back-to-back practice sessions?
- Between consecutive heats or practice flights, resist the urge to charge the battery to absolute maximum—a partial top-up is often sufficient and gentler on the li-ion cells than repeated full-charge cycles within short timeframes. Allow the battery to cool for a few minutes after a hard flight before plugging it in; warm cells charging immediately can generate excess heat and stress. If you're running multiple packs in rotation, you'll naturally spread charging cycles across your fleet, which is ideal for overall longevity.
- How is this charge time calculated?
- We divide the energy needed (74 Wh times the percentage you're charging) by the charger's effective power, which is the charger's wattage times the battery chemistry's real-world charging efficiency (85% for Lithium-ion (Li-ion / Li-Po)). The same formula powers both this page and our API.
ChargeTimeCalculatorestimates are based on typical charger efficiency and battery chemistry, not a live connection to your device. Always follow your manufacturer's charging guidance.