Panasonic integrates standard safety mechanisms into the NCR21700T:
The Panasonic NCR21700T uses standard LiNiCoAlO2 (NCA) chemistry – similar to Tesla cells. Charging requirements:
| Parameter | Recommended | Absolute Max | |-----------|-------------|---------------| | Charge voltage | 4.20 V | 4.25 V (risk of plating) | | Standard charge current | 1.5 A (0.3C) | – | | Fast charge current | 3.0 A (0.6C) | 4.0 A (must cut off at 4.20V) | | Trickle charge (below 2.5V) | Do not apply – cell considered damaged | | | Temperature range | 0°C to +45°C | – | panasonic ncr21700t datasheet
Critical warning from the datasheet: Do not charge below 0°C. Lithium plating occurs, causing internal short circuits. Also, do not float charge – terminate when current drops to <100 mA.
| Parameter | Value | Reviewers' Take | |-----------|-------|------------------| | Nominal Capacity | 4800 mAh (0.2C discharge) | Excellent for 21700 format. Slightly above the common 4500-5000 mAh range. | | Nominal Voltage | 3.6V (3.7V typical) | Standard Li-ion. | | Max Discharge Current | 2C (9.6A continuous) / 4C (19.2A pulse) | Major limitation. This is a low-drain cell. | | Standard Charge | 1.4A (0.3C) | Very slow by modern 21700 standards. | | Fast Charge | 3.2A (0.67C) | Still slow. Compare to Samsung 50G or LG M50LT (1C+). | | Max Charge Voltage | 4.20V ±0.03V | Standard, not high-voltage (4.35V). | | Cut-off Voltage | 2.5V | Standard. | | Internal Resistance | ≤ 40 mΩ (AC IR) | Good, but not exceptional (high-power cells are ~10 mΩ). | | Weight | ~69g | Very light for capacity – good energy/weight ratio. | | Operating Temp | Charge: 0~45°C / Discharge: -20~60°C | Standard range. | | Parameter | Value | Reviewers' Take |
The cell utilizes the NCA (Nickel Cobalt Aluminum Oxide) cathode chemistry.
While many high-power cells have a flat discharge curve that drops sharply near the end, the NCR21700T offers a very smooth, gradual slope. This allows devices with simple voltage-based fuel gauges to estimate remaining capacity with reasonable accuracy. While many high-power cells have a flat discharge
Model: NCR21700T
Type: Rechargeable Li-ion (Nickel-Cobalt-Aluminum Oxide chemistry)
Nominal Voltage: 3.6 V
Typical Capacity: 4500 – 4800 mAh (depending on discharge rate)
Minimum Capacity: 4350 mAh
Energy: ~16.2 Wh