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Product Description:
The Samsung SDI INR21700-40T is a premium-grade 21700 lithium-ion battery cell engineered for extreme high-power, high-torque applications. This 2pcs bundle delivers a true 4000mAh capacity, an impressive 40A (10C) continuous discharge current, and an ultra-low internal resistance as low as 8mΩ (flat type), providing explosive, sustained power for the most demanding devices.
Manufactured by Samsung SDI, a global leader in battery technology, the 40T cell offers a 1000+ cycle life with ≥90% capacity retention. It features a built-in safety valve with an explosion-proof design, safely venting internal gases to prevent swelling or rupture. Every single cell is individually tested and measured before shipping to ensure genuine capacity and consistent 8mΩ internal resistance.
To suit your specific project needs, we offer 5 customized options:
Flat Top (2pcs): Standard 21mm x 70mm flat terminal (8mΩ IR).
Button Top (2pcs): 21mm x 73mm with a protruding nub for recessed contacts (~12mΩ IR).
Spot-Welded Tabs (2pcs): Pre-welded nickel strips for easy connection (8mΩ IR).
Wired (Red/Black) (2pcs): Pre-soldered positive and negative wires for plug-and-play convenience (8mΩ IR).
Built-in Protection Board (2pcs): Includes over-charge, over-discharge, and over-current protection (5A discharge limit; size: 21.5mm x 75mm).
Key Features:
2pcs of Authentic Samsung SDI INR21700-40T Cells: Premium-grade, top-tier 21700 Li-ion battery.
4000mAh True Capacity: Provides 4000mAh of reliable energy for extended runtimes.
40A (10C) High Continuous Discharge: Delivers an extreme 40A power output with minimal voltage sag.
Ultra-Low Internal Resistance (8mΩ Flat): Ensures virtually no heat generation and maximum power transfer efficiency.
Individually Tested Before Shipping: Every cell undergoes rigorous testing to confirm 8mΩ IR and true capacity.
1000+ Cycle Life (≥90% Retention): Offers excellent long-term value and durability.
Built-In Safety Valve: Explosion-proof design safely releases internal gases in extreme conditions.
Versatile 5 Options: Choose from Flat Top, Button Top, Welded Tabs, Wired, or Protected versions.
Product Parameters (Based on Provided Specs):
Brand: Samsung SDI
Model: INR21700-40T
Size: 21700
Capacity: 4000mAh (Typical) / 3900mAh (Minimum)
Nominal Voltage: 3.7V / 3.6V
Full Charge Voltage: 4.2V
Continuous Discharge Current: 40A (10C)
Internal Resistance: 8mΩ (Flat/Welded/Wired) / ~12mΩ (Button)
Weight: Approx. 68g
Cycle Life: ≥ 1000 cycles (≥90% retention after 1000 cycles)
Safety: Positive terminal safety valve, explosion-proof design
Dimensions (Based on Variant):
Flat Top / Welded / Wired: 21mm (Dia) x 70mm (H)
Button Top: 21mm (Dia) x 73mm (H)
Protected Board: 21.5mm (Dia) x 75mm (H)
Pack Quantity: 2pcs (Selectable)
Applications:
High-Torque Cordless Power Tools: Drives heavy-duty drills, impact drivers, and saws demanding 40A burst power.
High-Performance RC Hobbies & Drones: Sustained high-current power for high-torque RC cars and professional UAVs.
Electric Scooters & Light EV Conversions: Reliable high-power cells for e-scooter and e-bike battery packs.
High-Capacity Portable Power Stations: Ideal core cell for building high-power portable energy storage systems.
Professional Automotive & Industrial Equipment: High-performance reliability for demanding industrial machinery and tools.
Frequently Asked Questions (FAQ):
Q1: What is the discharge current of this 40T battery?
A1: The Samsung 40T is rated for an impressive 40A (10C) continuous discharge current, making it one of the most powerful 21700 cells available for high-drain applications.
Q2: What is the advantage of the 8mΩ ultra-low internal resistance?
A2: 8mΩ is an exceptionally low resistance for a 21700 cell. This means the battery generates virtually no heat and loses almost no energy during 40A discharge, maximizing performance and minimizing thermal stress on your equipment.
Q3: Is every cell tested before shipping?
A3: Yes. As shown in our product images, every single cell is individually tested before shipping. We measure and confirm the internal resistance (8mΩ) and capacity to ensure you receive the genuine product you paid for.
4Q: What kind of charger should I use for this battery?
A5: You must use a charger specifically designed for 3.6V/3.7V Li-ion batteries with a 4.2V cut-off voltage. A smart charger with over-charge protection is highly recommended.
Free Shipping: Enjoy free shipping on all orders over $65. For orders under $65, the shipping cost is $8.99.
Delivery Time: Once shipped, orders typically arrive within 7–15 business days.
Easy Returns: We want you to be completely satisfied. If you're not, you can return your product within 30 days of receiving your order. Please ensure the items are unused and in their original condition. For return instructions, please contact our support team.
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Samsung quality at its finest. 40T remains one of the best high-drain 21700 cells available.
40T offers more capacity than 30T with slightly less discharge. Perfect for my applications needing runtime.
Used by major tool manufacturers. Proven reliability. The 21700 cell for serious power applications.
If you're rebuilding tool batteries, Samsung 40T is the best combination of power and capacity.
40A discharge with 4000mAh capacity. 8m times IR is incredibly low. Perfect for my high-drain power tools.
At OneAndes, we are committed to providing high-quality cylindrical lithium-ion batteries for your drones, vacuums, garden tools, and other power needs. If you are not completely satisfied with your purchase, we are here to help. Please read our full return policy below before initiating a return.
1. Return Window
You have 30 calendar days from the date you received your item(s) to request a return. Any return request submitted after 30 days will not be eligible for a refund or exchange.
2. Eligibility Conditions
To qualify for a return, all items must meet the following conditions:
Condition: Items must be unused, undamaged, and in the same condition that you received them.
Packaging: Items must be returned in their original packaging with all accessories, manuals, and protective covers intact.
Proof of Purchase: A valid receipt, order confirmation email, or proof of purchase must accompany all returns.
Non-Returnable Items:
Batteries that have been installed, used, or show any signs of wear.
Items marked as “Final Sale” or “Clearance” at the time of purchase.
Customized or special-order products.
Gift cards.
If a returned item fails to meet these conditions, we reserve the right to deny the return or charge a restocking fee.
3. How to Initiate a Return
Follow these steps to return your product:
Contact Us: Email our support team at support@oneandes.com with your order number and the reason for return. We aim to respond to all return requests within 24 hours on business days.
Receive RMA: We will provide you with a Return Merchandise Authorization (RMA) number and return instructions. Do not ship any item without an RMA number.
Pack Securely: Place the item in its original packaging, include all accessories, and clearly write the RMA number on the outside of the box.
Ship to Our US Warehouse: Ship the package to the following address:
OneAndes Returns
10320 6th St
Rancho Cucamonga, CA 91730
USA
*Important: Lithium-ion batteries are classified as hazardous materials (Class 9). Please follow the shipping guidelines provided in Section 4 below. We recommend using a trackable shipping service and purchasing shipping insurance, as we cannot guarantee receipt of your returned item.*
4. Return Shipping Costs
Defective or Incorrect Items: If the item you received is defective, damaged in transit, or different from what you ordered, OneAndes will cover the return shipping cost. In this case, we will provide you with a prepaid return shipping label.
Buyer’s Remorse / Non-Defective Returns: If you are returning an item for any other reason (e.g., no longer needed, ordered the wrong model), you are responsible for the return shipping costs. You must prepay the return shipping cost using a trackable carrier that accepts lithium batteries. We do not provide prepaid return labels for non-defective returns.
Lithium Battery Shipping Regulations: By law, all returns must be shipped in compliance with applicable dangerous goods regulations. We will provide guidance on proper packaging and labeling. Failure to comply may result in carrier refusal, seizure, or additional fees. We are not responsible for returned items lost or rejected by the carrier due to improper shipping.
5. Refunds
Once we receive and inspect your return at our Rancho Cucamonga, CA facility, we will notify you via email of the approval or rejection of your refund.
Approved Refunds: If approved, your refund will be processed to your original method of payment within 5 to 10 business days. Please note that depending on your bank or credit card issuer, it may take additional time for the credit to appear on your statement.
Partial Refunds: In certain situations, only partial refunds may be granted:
Items not in original condition, missing parts, or damaged for reasons not due to our error.
Items returned more than 30 days after delivery (reviewed on a case-by-case basis).
Non-Refundable Fees: Original shipping charges are non-refundable unless the return is due to our error (defective product or incorrect shipment).
Restocking Fee: We do not charge a restocking fee for defect-free returns, but we may deduct the return shipping cost, which will be deducted from your refund.
6. Exchanges
We replace items only if they are defective or damaged upon arrival. If you need to exchange a defective item for the same product, please contact us at support@oneandes.com. Exchanges are subject to product availability.
If you ordered the wrong battery size or model, please follow the standard return process above and place a new order for the correct item.
7. Damaged or Missing Items
If your package arrives visibly damaged, please take photos of the package before opening and contact us immediately. We will work with the shipping carrier to file a claim and arrange for a replacement or refund. Damaged or missing item claims must be reported within 7 calendar days of delivery. For immediate assistance, you may also call us at (213) 316-8849.
8. Order Cancellation
You may cancel your order without penalty if it has not yet been shipped. To cancel, email us at support@oneandes.com as soon as possible. If the order has already been processed or shipped, you will need to follow the standard return process upon receipt.
9. Warranty
All OneAndes batteries are backed by a 12-month limited warranty against defects in materials and workmanship. This warranty does not cover damage caused by misuse, improper charging, unauthorized modifications, normal wear and tear, or use outside of manufacturer specifications. For warranty claims, please contact our support team.
10. Contact Us
If you have any questions about our Return & Refund Policy, please reach out:
Email: support@oneandes.com
Phone: (213) 316-8849 (Mon-Fri, 9 AM – 5 PM Pacific Time)
Mailing Address: 10320 6th St, Rancho Cucamonga, CA 91730, USA
We aim to respond to all inquiries within 24 hours during business days. Please include your order number for faster assistance.
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