Samsung 25R 2500mAh 20A Button Top Battery 4-Pack with Nitecore UMS4 Smart Charger – High-Drain Power Kit with LCD Control for Flashlights & Power Tools
Description
What's in This Bundle
- 4x Samsung INR18650-25R, 2500mAh, Button Top
- 1x Nitecore UMS4 4-slot LCD USB-C charger
- Cable and manual included with the charger
A complete kit for anyone running a 4-cell high-drain device or building a small pack — four matched, genuine 25R cells paired with a charger that reports real per-cell health, not just charge status.
This listing is for Button Top. Looking for Flat Top? Click here to buy: Samsung INR18650-25R Flat Top + Nitecore UMS4 Bundle.
Why This Pairing Makes Sense
The 25R is one of the classic high-drain 18650 cells — moderate capacity, a strong 20A continuous discharge rating, and a long track record in mods, RC applications, tools, and custom packs. Four cells bought together as a matched set means consistent capacity and internal resistance across the group, which matters more for a high-drain cell like this one, where mismatched internal resistance between cells shows up faster under load.
The Nitecore UMS4 pairs especially well here because it doesn't just charge the cells — it measures and displays internal resistance for each slot with a "Good" or "Poor" health rating. For a high-drain cell where internal resistance directly affects real-world performance, that's a genuinely useful way to confirm all four cells are actually matched, not just similarly labeled.
Samsung 25R — Battery Specs
| Parameter | Value |
|---|---|
| Brand & Model | Samsung SDI INR18650-25R |
| Capacity | 2,500mAh standard discharge (2,450mAh rated at 10A) |
| Nominal Voltage | 3.6V |
| Full Charge Voltage | 4.2V |
| Discharge Cutoff Voltage | 2.5V |
| Max Continuous Discharge | 20A |
| Max Charge Current | 4A (standard charge: 1.25A) |
| AC Impedance | ≤18mΩ (1kHz, initial) |
| Terminal Type | Button Top |
| Protection Circuit | None (unprotected cell) |
| Weight | 45g max |
This is a genuine high-drain cell, verified against Samsung's official datasheet — not rewrapped or relabeled stock. The 25R is often run close to its current ceiling in real devices, so heat management in your build matters more here than it would with a lower-drain cell.
This listing is for Button Top. For Flat Top click here
Nitecore UMS4 — Charger Specs
| Parameter | Value |
|---|---|
| Input | DC 5V⎓2A / 12V⎓1.5A, 18W max |
| Output Voltage | 4.35V / 4.2V / 3.7V / 1.48V (±1%, auto-selected by battery type) |
| Fast Charge Mode | 3000mA×1 / 2000mA×2 / 1000mA×4 (max) |
| Standard Charge Mode | 2000mA×1 / 1000mA×2 / 500mA×4 (max) |
| Adjustable Settings | Charge current 300mA-3000mA, charge voltage 3.7V/4.2V/4.3V (manual override available) |
| Display | Backlit LCD — per-slot voltage, current, charge time, capacity, and internal resistance (mΩ) with Good/Poor health rating |
| Special Features | IMR-optimized charging profile, lithium battery repair function for over-discharged cells, activation for protected cells |
| Dimensions | 159mm x 107mm x 41mm |
| Weight | 255.4g (charger only) |
| Compatible Cell Sizes | 10440 through 26700 across Li-ion/IMR/LiFePO4, plus Ni-MH/Ni-Cd (AA/AAA/AAAA/C/D) |
| Safety | Reverse polarity and short-circuit protection (flashing "EE" alarm), automatic temperature control, PC fireproof housing |
A realistic note on charge time: with all four slots occupied, the UMS4's fast charge mode delivers roughly 1000mA per slot — well within the 25R's 4A max charge rating, so there's real margin here. Expect a full charge in roughly 2.5-3 hours for all four cells at once, genuinely quick for a 4-slot charger running this many cells simultaneously.
Why the Internal Resistance Readout Matters Here
High-drain cells like the 25R are exactly where internal resistance differences between cells matter most — a cell with meaningfully higher resistance than its packmates will run hotter and sag more under load, dragging down the performance of a series or parallel pack even if its capacity looks fine on paper. The UMS4's per-slot mΩ readout and health rating let you actually check this instead of assuming four cells from the same order are automatically matched.
Where the 25R Actually Shines
- RC applications — cars, planes, and similar hobbies that need real current delivery
- Power tools and custom packs where discharge capability matters more than maximum runtime per cell
- Robotics and DIY builds needing dependable current under load, verified before assembly
Not the ideal pick if capacity or runtime matters more to you than raw discharge current — a cell like the 30Q or 35E will serve you better in that case.
Things Worth Knowing Before You Use This Kit
- The 25R is an unprotected cell. The charger enforces its own voltage and current cutoffs, but your device still needs to handle discharge-side protection.
- Don't mix these cells with older ones you already own, even if they're also 25R — the UMS4's internal resistance readout is exactly the tool for checking this before you combine batches.
- This cell runs warm at its rated ceiling. That's expected behavior for a 20A cell pushed toward that limit, not a defect — but ventilation and enclosure design in your build matter.
Frequently Asked Questions
Can this charger handle the 25R's full capacity safely? Yes. Even at the UMS4's fast charge rate of roughly 1000mA per slot with all four bays occupied, that's comfortably under the 25R's 4A max charge rating — a full charge takes roughly 2.5-3 hours for all four cells.
What does the "Poor" health rating actually tell me? It means that cell's measured internal resistance is elevated relative to what's expected for a healthy cell. For a high-drain cell like the 25R, that's worth taking seriously — a "Poor" rating suggests the cell may underperform or run hotter than its packmates under load.
Why does the 25R run hotter than lower-drain cells like the 35E? It's a direct consequence of the design trade-off — the 25R prioritizes current delivery (20A continuous) over capacity, and pushing more current through a cell generates more heat. This is expected and within the cell's rated tolerance.
Can I charge two different battery sizes at once? Yes — the UMS4's four slots operate independently, so you can mix cell sizes or even Ni-MH/Ni-Cd batteries across the slots if needed.
What does the lithium battery repair function do? When an over-discharged IMR lithium cell is detected, the display shows an "EE EE" prompt; pressing the V button attempts a controlled repair charge. It won't recover every over-discharged cell, but it gives borderline cells a real chance before writing them off.
In stock now. This bundle ships as a matched set of four genuine Samsung 25R Button Top cells with a verified Nitecore UMS4 charger — ready for mods, RC, tools, and other high-drain builds out of the box.
Shipping and Returns
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Free Shipping: Enjoy free shipping on all orders over $65. For orders under $65, the shipping cost is $8.99.
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Delivery Time: Once shipped, orders typically arrive within 7–15 business days.
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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.
Payment & Security
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Refund Policy
OneAndes Return & Refund Policy
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:
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Condition: Items must be unused, undamaged, and in the same condition that you received them.
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Packaging: Items must be returned in their original packaging with all accessories, manuals, and protective covers intact.
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Proof of Purchase: A valid receipt, order confirmation email, or proof of purchase must accompany all returns.
Non-Returnable Items:
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Batteries that have been installed, used, or show any signs of wear.
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Items marked as “Final Sale” or “Clearance” at the time of purchase.
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Customized or special-order products.
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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:
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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.
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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.
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Pack Securely: Place the item in its original packaging, include all accessories, and clearly write the RMA number on the outside of the box.
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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
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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.
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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.
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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.
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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.
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Partial Refunds: In certain situations, only partial refunds may be granted:
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Items not in original condition, missing parts, or damaged for reasons not due to our error.
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Items returned more than 30 days after delivery (reviewed on a case-by-case basis).
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Non-Refundable Fees: Original shipping charges are non-refundable unless the return is due to our error (defective product or incorrect shipment).
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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:
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Email: support@oneandes.com
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Phone: (213) 316-8849 (Mon-Fri, 9 AM – 5 PM Pacific Time)
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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.