The technical datasheet outlines the foundational boundaries of the NCR21700T. Understanding these absolute ratings ensures optimal performance and prevents premature cell degradation. Physical Dimensions 21700 (Cylindrical) Diameter: 21.1 mm (Maximum) Length: 70.4 mm (Maximum) Weight: Approximately 68.0 grams Electrical Capacity and Voltage Nominal Capacity: 4800 mAh (Typical) Minimum Capacity: 4700 mAh Nominal Voltage: 3.6V – 3.7V Charging Voltage: 4.20V ± 0.05V Discharge Cut-off Voltage: 2.5V Current and Discharge Ratings Standard Charge Current: 1.5A to 2.4A
The Panasonic NCR21700T uses standard chemistry – similar to Tesla cells. Charging requirements:
Panasonic is very clear on this: The NCR21700T is designed for spot-welded nickel strips. Soldering irons transfer too much heat into the cell, melting the internal separator and causing an internal short. If you see a loose NCR21700T with solder blobs on it, run away.
This article is for informational purposes only. It is based on the technical specifications typically associated with the Panasonic NCR21700T cell. Always consult the official manufacturer datasheet for precise engineering data before designing battery packs or electronic devices.
While the cell boasts a high nominal capacity of 4800mAh, its internal resistance is optimized to support high-drain applications. It can comfortably sustain continuous discharge currents up to 15A without significant voltage sag. Under controlled thermal conditions (where cell temperature does not exceed 60°C), peak bursts or elevated continuous discharge up to 20A can be achieved, though this may accelerate cycle degradation. Environmental and Temperature Limits panasonic ncr21700t datasheet
The charger applies a steady current (typically 2.3A for standard longevity) until the cell voltage reaches 4.2V.
If you are currently engineering a battery pack with this cell, let me know you are planning (e.g., 10S2P, 13S4P), the maximum continuous current draw your system requires, or what type of cooling/housing you plan to use so we can optimize your thermal and electrical design.
Charge at 2500mA (0.5C) until the voltage reaches 4.2V.
The Panasonic NCR21700T is a 21mm x 70mm cylindrical lithium-ion battery with a nominal voltage of 3.6V and a capacity of 4000mAh. The battery is designed to provide a high level of energy density, making it an ideal choice for applications where space and weight are limited. Charging requirements: Panasonic is very clear on this:
I can provide specific or thermal management advice based on your needs. Share public link
How does the Panasonic NCR21700T compare to alternatives? Here’s a quick reference table:
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), some voltage sag will occur, causing the discharge curve to shift downward. Designers must account for this by configuring low-voltage cut-offs within the BMS to avoid premature system shutdowns under heavy load. Cycle Life Expectancy When cycled under standard conditions ( discharge down to ), the cell retains roughly This article is for informational purposes only
Used in residential solar battery banks and off-grid power stations due to its long shelf-life and density.
Immediate disconnection in the event of an external short. 6. Primary Applications
Deep Dive: Panasonic NCR21700T Li-ion Battery Datasheet Explained
The cell offers a volumetric energy density of approximately 775 Wh/l and a gravimetric density of 263 Wh/kg , making it highly efficient for its weight and size.