Samsung 40T Battery 21700 4000mAh 30A

Order dispatch date: dispatch the same working day for orders placed by 3pm

Price: €14.99

Regular price:

14.99

quantity UNIT

You gain 14 points [?]

product unavailable

Vendor: Samsung SDI

Description

Samsung INR21700-40T 4000mAh – 35A CDR | 45A (80°C Temp Cut)

The Samsung INR21700-40T is a high-drain lithium-ion 21700 cell manufactured by Samsung SDI. It combines strong usable capacity with high continuous discharge capability for regulated high-performance applications.

This is an unprotected industrial cell and must only be used in regulated systems equipped with appropriate battery management and protection circuitry.

Cell Identity & Core Specifications

View Core Technical Data

Parameter	Specification
Manufacturer	Samsung SDI
Model	INR21700-40T
Format	21700 Flat Top
Standard Discharge Capacity	≥ 4000 mAh
Rated Discharge Capacity	≥ 3900 mAh
Nominal Voltage	3.6 V
Max Charge Voltage	4.20 V
Cut-off Voltage	2.5 V

Discharge & Charging Parameters

View Current Ratings

Parameter	Specification
Max Continuous Discharge (no temp cut)	35 A
Max Continuous Discharge (80°C monitored)	45 A
Standard Charge (CCCV)	2.0 A
Fast Charge (CCCV)	6.0 A
Initial AC Internal Impedance	≤ 12 mΩ (1kHz)

For stable operation in consumer systems, treat 35A as the primary ceiling. The 45A value applies only when active thermal monitoring limits cell surface temperature to 80°C.

Dimensions & Weight

View Physical Specifications

Parameter	Specification
Diameter	Max 21.22 mm
Height	Max 70.30 mm
Weight	70 g max

Operating Temperature

View Temperature Limits

Condition	Range
Charge (ambient)	0°C – 45°C
Discharge (ambient)	-20°C – 60°C
Discharge (surface monitored)	Up to 80°C

Samsung 21700 battery safety guide infographic with charging temperature limits, 35A warning and 2.5V cut-off

Application Context

High-current 21700 cell designed for regulated systems where runtime and discharge capability must remain balanced without reliance on temperature-cut operation.

Battery Safety Notice

Never carry loose batteries in pockets.
Do not use cells with damaged wraps.
Avoid contact with metal objects.
Use dedicated 21700 lithium-ion chargers.
Discontinue use if overheating or abnormal behaviour occurs.
Use in unregulated systems requires full understanding of Ohm’s Law and battery safety limits.

Technical FAQ – Samsung INR21700-40T

Is 35A the primary continuous discharge rating?

Yes. 35A is the maximum continuous discharge rating without a temperature cut and should be treated as the primary operational ceiling for stable use.

What does 45A (80°C temp cut) mean?

45A is specified only when cell surface temperature is actively limited to 80°C. It is a temperature-monitored condition, not a general-purpose rating.

What is the difference between standard and rated capacity?

Standard discharge capacity is specified as ≥4000 mAh under low-current test conditions. Rated discharge capacity is specified as ≥3900 mAh under the rated test method and represents a tighter guaranteed minimum.

How can authenticity be screened quickly?

Check wrap and top insulator ring condition, verify dimensional tolerances, and compare behaviour against expected low-impedance performance. Significant anomalies can indicate non-original supply.

Recycling & Compliance – Ireland

Recycle according to Irish WEEE regulations.

WEEE Ireland – Battery Collection Points

This product is intended for adults aged 18+ in Ireland.

Last updated: 19 February 2026 – Verified against Samsung SDI technical documentation.