3.7V 21700 4000mAh 10C Lithium Ion Battery Cell INR21700 High Discharge Rate 40A
3.7V 21700 4000mAh 10C Lithium Ion Battery Cell | High Discharge 40A Power for E-Bikes, Drones & Vaping Devices
3.7V 21700 4000mAh 10C Lithium Ion Battery Cell (INR21700) delivers exceptional energy density, ultra-low internal resistance, and continuous 10C (40A) high discharge capability. Designed for E-bikes, drones, e-cigarettes, power tools, and high-performance electronics, this cell offers over 500 cycles with 80% capacity retention, up to 95% discharge efficiency, and minimal heat generation. Fully customizable in size, voltage, capacity, and OEM design, it’s the ideal power source for demanding applications requiring both endurance and stability.
21700 Cells Lithium Battery Specification
Model: 21700
Rated Capacity: 4000mAh
Minimal Capacity: 3950mAh
Energy: 14.8Wh
Energy Density: 214.5Wh/kg
Rated Voltage: 3.7V
Discharge Cut-off Voltage: 2.75V
Charge Cut-off Voltage: 4.2V
Cycle Life: More than 500 cycles
Dimensions: Φ21*70mm
Weight: 69g
Internal Resistance: Less than 10m Ω
Standard Discharge Current: 0.2C (800mA)
Standard Charge Current: 0.2C (800mA)
Max Continuous Discharge Rate: 10C (40A)
Max Continuous Charge Current: 2C (8A)
Charging Temperature: 0 to 45℃;
Discharge Temperature: -20 to 65℃
Storage Temperature:
- -20℃~25℃: 12 months
- -20℃~45℃: 3 months
- -20℃~60 ℃: 1 month
Key Features — 21700 li ion battery
High Energy Density in a Compact Size
The INR21700 4000mAh cell features high gravimetric and volumetric energy density, delivering more capacity in the same space compared to standard 18650 batteries. Its 3.7V nominal voltage and 4000mAh capacity provide reliable, high-output energy ideal for long-range and performance-demanding devices such as E-bikes, UAVs, and portable electronics.
Long Cycle Life (500+ Cycles @ 80% Capacity)
This high-performance lithium-ion cell maintains over 80% of its original capacity after 500 charge–discharge cycles, ensuring long-term durability and consistent performance. Designed with advanced electrode materials and optimized electrolytes, it guarantees stable cycling efficiency and low degradation.
10C Continuous High Discharge Rate (Up to 40A)
With a continuous discharge current of 40A (10C), the INR21700 battery excels in high-load applications. Its superior power output makes it ideal for:
Electric bicycles and scooters (E-bike packs)
Drones and RC models
E-cigarettes and vaping devices
Power tools and motorized equipment
Low Internal Resistance & High Efficiency
With low internal resistance design, this cell maintains up to 95% discharge efficiency, significantly reducing heat buildup during operation. This not only improves safety and performance but also extends the battery’s lifespan, especially under heavy continuous loads.
Custom Battery Pack Solutions
Cestpower offer OEM and ODM customization services to meet diverse technical and branding requirements:
Custom battery pack configurations (series/parallel)
Adjustable capacity, voltage, and dimensions
OEM printing, barcode labeling, sleeves, and packaging
Integration with connectors, plug types, and protection circuits (BMS/PCM)
Tailored designs for E-bikes, drones, vaping, medical, and industrial applications
Safety and Reliability
Built with high-quality INR chemistry, the cell provides excellent thermal stability, overcurrent protection, and low risk of swelling or leakage. Advanced manufacturing ensures compliance with UL, CE, and RoHS standards for dependable performance.
Frequently Asked Questions (FAQ)
What makes 21700 battery better than standard 18650 cell?
The 21700 format offers higher capacity and current output, improved thermal management, and greater energy density in a slightly larger size.
Can this cell handle continuous high-load usage?
Yes. With 10C (40A) continuous discharge capability and low heat generation, it performs reliably under constant high-power operation.
How long will this battery last?
It retains at least 80% capacity after 500 cycles, depending on the charging method and application.
Is this cell suitable for E-bike or drone battery packs?
Absolutely. The high discharge rate and low internal resistance make it ideal for E-bike, UAV, and high-power applications.
Do you offer OEM customization or private labeling?
Yes. Cestpower provide full OEM/ODM customization, including capacity, packaging, connectors, and branding to fit your specific project.
Related Battery
3.7V 21700 3000mAh Lithium Ion Battery Cell
