Senchtec 21700 4000mAh 3.7V 15c Discharge Rechargeable Long Lasting Lithium Ion Battery

• Customization: Available
• Type: Li-ion Battery
• Cathode Material: NCM
• Rechargeable: Yes
• Size: 21700
• Standard Discharge Capacity: Min. 4000mAh-0.2c(800mA), 2.5V Cut-off
• Rated Discharge Capacity: Min. 3900mAh-10.0c(40A), 2.5V Cut-off
• Nominal Voltage: 3.7V
• Standard Charge: 0.5c(2A) Cc (Constant Current) Charge to 4.2V
• Rated Charge: 2c(8A) Cc (Constant Current) Charge to 4.2V
• Charging Time: Standard Charge: 140min / 80mA Cut-off
• Max. Continuous Discharge: 60A
• Max Pulse Discharge: 140A 5s
• Charge Cut-off Voltage: 4.2V
• Discharge Cut-off Voltage: 2.5V
• Cycle Life: Capacity ≥2, 400mAh @ After 600cycles
• Initial Impedance: Max 4MΩ
• Cell Weight: 70.0g Max
• Cell Dimension(with Tube): Height : Max 70.42mm, Diameter : Max 21.31mm
• Operating Temperature (Surface): Charge:-10 to 60ºC, Discharge:-30 to 75
• Transport Package: Plastic Lining, Carton Packaging
• Specification: 21x70mm
• Trademark: Senchtec
• Origin: China
• HS Code: 8507600090
• Production Capacity: 1, 000, 000 Units/Month

Product Description

21700 4000mAh 3.7V 15C High Discharge Rate Rechargeable Ternary Li-ion Lithium Battery Cell
Full-tab design, ultra-low internal resistance.
Low temperature rise, fast charging, long cycle life.
Supports -40°C-60°C low-temperature operation and high power.
Applications:Power tools,drones,model aircraft,FPV drones,agricultural drones,remote-controlled aircraft,model boats,model cars,robots,submarines,and more.

 

Charge Current:5A  Capacity:4.04Ah  Energy:15.57Wh

 

Discharge Current:10A  Capacity:3.97Ah  Energy:14.29Wh

 

Discharge Current:20A  Capacity:4.02Ah  Energy:14.12Wh

 

Discharge Current:40A  Capacity:4.04Ah  Energy:13.37Wh

 

 

 

SCT40 - Complete Technical Datasheet

1. General Specifications

Parameter	Value	Test Conditions
Model Number	SCT40	Manufacturer: Senchtec
Chemistry	Lithium-Ion (Li-ion)	Cathode: NCM811 / Anode: Silicon-Carbon Composite
Nominal Voltage	3.6V	Average voltage during 0.2C discharge
Rated Capacity	4000mAh (4.0Ah)	Discharged at 0.2C (800mA) to 2.5V, 25°C ±2°C
Minimum Capacity	3900mAh	Per manufacturer tolerance
Energy	14.4Wh	Calculated (3.6V × 4.0Ah)
Internal Resistance (AC)	≤3mΩ	Measured at 100% SOC, 1kHz AC impedance, 25°C
Weight	68g ±2g	Without terminals
Dimensions	21.1mm (D) × 70.1mm (H)	Tolerance: ±0.1mm

 

2. Electrical Performance

Parameter	Value	Test Conditions
Standard Charge	CC-CV, 4.2V, 4.0A (1C)	Cut-off: 0.05C (200mA) / Time: ~2.5 hours
Fast Charge	CC-CV, 4.2V, 8.0A (2C)	Cut-off: 0.05C / Not recommended for cycle life
Max Charge Current	12A (3C)	Limited by temperature rise (T ≤45°C)
Charge Temperature	0°C to 45°C	Optimal: 25°C
Continuous Discharge	45A (11.25C)	Max current without exceeding 80°C cell temperature
Peak Discharge (Pulse)	60A (15C) for ≤5s	25°C, 50% SOC
Discharge Cut-off	2.5V	Lower limit to prevent damage
Operating Temperature	Discharge: -20°C to 60°C	Charge: 0°C to 45°C

 

3. Cycle Life & Durability

Parameter	Value	Test Conditions
Cycle Life	≥1000 cycles	1C charge/discharge (4.0A), 100% DOD, 25°C (to 80% initial capacity)
Storage Life	12 months (25°C)	Capacity recovery ≥85% after storage at 50% SOC
Self-Discharge Rate	≤2% per month	At 25°C, 50% SOC

 

4. Thermal & Safety

Parameter	Value	Test Conditions
Thermal Runaway	>160°C	Catastrophic failure temperature (per UN38.3)
Certifications	UN38.3, IEC62133, CE, RoHS	Complies with global transport/safety standards
Protection Devices	CID + PTC	Current interrupt (CID) and thermal fuse (PTC) integrated

 

5. Discharge Performance

• Voltage vs. Capacity (25°C):

  • 0.2C (800mA): ~3.6V average, 4000mAh delivered.

  • 1C (4.0A): ~3.5V average, 3950mAh delivered.

  • 10C (40A): ~3.1V average, 3800mAh delivered.

• Energy Efficiency: ~92% at 5C discharge (25°C).

 

6. Key Advantages

1. Silicon-Carbon Anode:

   • Enables ≥4000mAh capacity with high-current support.

   • Reduced expansion vs. pure silicon (cycle life >1000 cycles).

2. NCM811 Cathode:

   • High energy density (≥270Wh/kg).

   • Optimized Ni content balances energy and thermal stability.

 

7. Comparison with Competing Cells

Model	Chemistry	Capacity	Max Continuous	Energy Density	Cycle Life
Ampace JP40	NCM811/Si-C	4000mAh	45A	270Wh/kg	1000 cycles
Samsung 40T	NCA	4000mAh	35A	252Wh/kg	500 cycles
Molicel P42A	NCM	4200mAh	45A	255Wh/kg	700 cycles

 

8. Application Notes

• Recommended Uses:

  • High-performance drones, power tools, EVs (secondary systems).

• Thermal Management:

  • Active cooling suggested for >30A continuous discharge.

• Storage:

  • Store at 30-50% SOC, 15-25°C for long-term health.
    
    
     

    Certificates: