Stage 1: Constant Current (CC) | Stage 2: Constant Voltage (CV) (Current is capped; Voltage rises) | (Voltage is locked; Current drops) --------------------------------------|------------------------------------ Current (A) : [====== Capped ======] | Current (A) : [== Tapering Down =>] Voltage (V) : [== Rising to 4.2V ==] | Voltage (V) : [==== Locked 4.2V ===]
The headline feature of the NCR21700T is its . In the world of cylindrical cells, this represents the upper echelon of energy density.
The 21700 designation refers directly to the mechanical dimensions of the cylindrical cell: Represents a diameter of 21 millimeters. 70: Represents a length of 70 millimeters. 0: Explains the standard cylindrical shape.
Frequently draining the cell completely down to 2.5V stresses the chemical structure. 5. Safety Protocols and Environmental Limits panasonic ncr21700t datasheet
| Parameter | Value | |---|---| | | NCR21700T | | Manufacturer | Panasonic / Sanyo | | Format | 21700 (Cylindrical) | | Nominal Capacity | 4,800 – 5,000 mAh (varies by source) | | Typical Capacity | 5,000 mAh | | Minimum Capacity | 4,900 mAh (some variants) | | Nominal Voltage | 3.6 V – 3.7 V | | Maximum Charge Voltage | 4.20 V ± 0.05 V | | Discharge Cut‑off Voltage | 2.50 V – 2.75 V (depending on variant) | | Standard Charge Current | 2 A (CC‑CV) | | Maximum Continuous Discharge Current | 10 A – 20 A (see discussion below) | | Maximum Pulse Discharge Current | 12 A – 35 A (pulse duration dependent) | | Internal Resistance | ≤ 14 mΩ (typical) | | Cycle Life | > 700 cycles (to 60 % capacity retention) | | Operating Temperature (Charge) | 0 °C to +45 °C | | Operating Temperature (Discharge) | −20 °C to +60 °C | | Diameter | 21 mm (± 0.2 mm) | | Height | 70 mm (± 0.3 mm) | | Weight | 66.8 g – 70 g | | Terminal Type | Flat‑top (positive terminal) | | Protection Circuit | Not integrated (PCM not present) |
Would you like a comparison of this cell against Samsung 50G or Molicel P42A for your specific project?
| Parameter | Specification | Notes | | :--- | :--- | :--- | | | NCA (Nickel Cobalt Aluminum) | LiNiCoAlO₂ / Graphite | | Nominal Capacity | 4800 mAh (4.8 Ah) | Standard discharge (0.2C) | | Minimum Capacity | 4750 mAh | | | Nominal Voltage | 3.6 V | Average operating voltage | | Charging Voltage | 4.20 V | Max voltage | | Discharge Cut-off | 2.50 V | Minimum voltage | | Max Charge Current | 4850 mA (approx. 1C) | Standard charging | | Max Discharge Current | 15 A (Continuous) | Temperature dependent | | Weight | Approx. 69g – 71g | | | Dimensions | Diameter: 21.15mmHeight: 70.15mm | Excluding terminals | | Energy Density | ~250 Wh/kg (Gravimetric) | Calculated based on weight | Stage 1: Constant Current (CC) | Stage 2:
Micro-cracking in the nickel-rich cathode and the growth of the Solid Electrolyte Interphase (SEI) layer on the anode gradually increase internal DC resistance (DCR) over time.
| Parameter | Specification | | :--- | :--- | | | NCR21700T | | Chemistry | Li-ion (NCA - Nickel Cobalt Aluminum) | | Nominal Capacity | 5000 mAh (5.0 Ah) | | Minimum Capacity | 4850 mAh | | Nominal Voltage | 3.6 V – 3.7 V | | Maximum Voltage | 4.2 V | | Cut-off Voltage | 2.5 V | | Maximum Continuous Discharge | 10 A (Typical recommended) | | Maximum Pulse Discharge | 15 A – 20 A (Short duration) | | Weight | Approx. 70g | | Dimensions | Diameter: 21.1mm | Height: 70.3mm | | Operating Temp (Charge) | 0°C to +45°C | | Operating Temp (Discharge) | -20°C to +60°C |
When integrating the NCR21700T into a project, the electrical and physical limits defined by the manufacturer must be strictly observed. Below is the data compiled from the official Panasonic datasheet. Electrical Characteristics Specification Typical capacity at standard discharge Minimum Capacity Guaranteed minimum rating Nominal Voltage 3.6V – 3.7V Mid-point of the discharge cycle Charging Voltage 4.20V ± 0.03V Maximum safe upper voltage limit Discharge Cut-off Voltage Minimum safe lower voltage limit Standard Charging Current 1.5A to 2.4A Recommended for maximum cycle life Max Continuous Discharge Current 10A to 15A Dependent on thermal management Physical Dimensions & Weight Diameter: 21.1 mm (Maximum) Length: 70.4 mm (Maximum) Weight: Approximately 68.0 grams Terminal Type: Flat top (Unprotected industrial cell) 3. Charging and Discharging Behavior Standard Charge Profile 70: Represents a length of 70 millimeters
For battery pack engineers, the physical dimensions and thermal behavior are just as important as electrical specs.
Because the NCR21700T prioritizes capacity (5000mAh) over high discharge rates, it is best suited for devices requiring long-lasting energy.
What is the required by your application?