EVE INR21700-50E 5000mAh 10A 21700 Battery 4-Pack with Nitecore UMS4 Smart Charger – High-Capacity Power Kit for Home Backup Systems, Multi-Device Camping Setups & Portable Energy Storage
Description
Why This Bundle
The EVE 50E is an energy-focused 21700 cell built for runtime rather than extreme current — a genuine 5000mAh capacity with a 15A maximum discharge rating, making it a strong choice for long-runtime flashlights, moderate-drain battery packs, and electric mobility modules where capacity per cell matters more than chasing peak amps. A set this capable deserves a charger that can handle every cell at once while keeping close watch on their health. This bundle pairs 4 genuine EVE INR21700-50E batteries with the NITECORE UMS4, a QC-enabled 4-slot charger with a detailed LCD display, independent bay control, and multiple layers of protection — ready to use straight out of the box.
EVE INR21700-50E Specifications
| Item | Spec |
|---|---|
| Model | EVE INR21700-50E (Flat Top) |
| Nominal Capacity | 5000mAh |
| Minimum Capacity | 4900mAh (0.2C discharge) |
| Nominal Voltage | 3.6V |
| Max Continuous Discharge | 15A |
| Max Charge Current | 10A |
| Charge Cutoff Voltage | 4.20V |
| Discharge Cutoff Voltage | 2.5V |
| Initial AC Impedance (1kHz) | ≤18mΩ |
| Chemistry | Li-ion, energy-focused |
| Cell Size | 21700 (approx. Φ21.15mm × 70.15mm, approx. weight 68g) |
| Terminal Type | Flat Top only |
| Protection Circuit | None (unprotected cell) |
| Typical Use | Long-runtime flashlights, moderate-drain battery packs, electric mobility, portable power systems |
Note: This is an energy/runtime-focused cell, not a high-drain one — its strength is long runtime and stable capacity in a 5000mAh-class 21700 format, not extreme continuous current.
This is an unprotected cell — avoid mixing with batteries of a different brand, model, or charge state, and inspect the wrap for damage before every use to prevent short circuits.
The Charger: NITECORE UMS4
- USB-C input with QC support: up to 4,000mA total output; up to 3,000mA on a single bay with a QC adapter — a much closer match to the 50E's charging needs than a basic dual-slot charger
- QC Mode output: 3,000mA×1 / 2,000mA×2 / 1,000mA×4 — Standard Mode: 2,000mA×1 / 1,000mA×2 / 500mA×4
- Independent 4-bay control: charge and monitor up to 4 batteries separately, with each bay unaffected by the others
- Detailed real-time LCD display: shows battery health (Good/Poor), internal resistance, charging current, voltage, battery type, charged capacity, charging time, cut-off voltage, and charging mode
- 3 automatic charging modes: CC, CV, and -dV/dt, selected automatically based on battery type and charge level
- Manual adjustment: set charging voltage and current for specialized battery types
- Safety features: automatic internal resistance detection, reverse-polarity and short-circuit protection, overtime charging protection, and over-discharged battery activation/restoration
- Fire-retardant PC/ABS housing with built-in temperature regulation
- Universal power input: works with wall adapters, power banks, and solar panels via USB-C
NITECORE UMS4 – Supported Battery Types & Voltage
Compatible with 3.6V/3.7V Li-ion, 3.8V Li-ion, 3.2V LiFePO4, and 1.2V Ni-MH/Ni-Cd batteries, including the EVE 50E (21700) in this bundle:
IMR/Li-ion/LiFePO4: 10440, 14500, 14650, 16500, 16340 (RCR123), 16650, 17350, 17500, 17650, 17670, 17700, 18350, 18490, 18500, 18650, 18700, 20700, 21700, 22500, 22650, 25500, 26500, 26650, 26700 Ni-MH/Ni-Cd: AA, AAA, AAAA, C, D
Output current: up to 3,000mA per bay (QC mode) / 4,000mA total
Compatibility Notes
The UMS4 uses spring-loaded contacts and its bays are sized to comfortably fit 21700 cells like the 50E. Unlike a basic dual-slot travel charger, the UMS4's per-bay output (up to 3,000mA with a QC adapter on a single bay) charges a large 5000mAh cell like this considerably faster.
Note: With all 4 bays occupied, each will charge more gently at up to 1,000mA (QC mode) or 500mA (standard mode) — a safe, reasonable pace for four large-capacity cells at once, though it will still take a few hours for a full charge given the 50E's capacity.
What's Included
- EVE INR21700-50E Battery × 4
- NITECORE UMS4 4-Bay Charger × 1
- USB-C Charging Cable × 1
- User Manual × 1
Safety Tips
- Store batteries in a proper case, keeping them away from loose metal objects to prevent short circuits
- Never disassemble, puncture, burn, or submerge the batteries
- Charge only with a genuine, compatible charger such as the NITECORE UMS4
- The 50E is an unprotected cell intended for compatible, purpose-built devices — do not use it in unauthorized or modified equipment
- Never discharge below 2.5V or charge above 4.2V
FAQ
Q: Can the NITECORE UMS4 charge EVE 50E batteries safely? A: Yes. The UMS4 automatically detects Li-ion chemistry and applies the correct charging voltage (4.2V) and current for 50E cells, with real-time monitoring on its LCD display, and its higher per-bay output charges these large-capacity cells noticeably faster than a basic low-current charger.
Q: Is the EVE 50E a high-drain cell? A: No, it's an energy-focused cell — 15A is its maximum discharge rating, and it's better suited to long-runtime flashlights, moderate-drain packs, and electric mobility applications than to devices demanding extreme continuous current.
Q: Can I charge all 4 batteries at the same time? A: Yes. The UMS4 has 4 independent bays and can charge all 4 cells simultaneously — up to 1,000mA per bay in QC mode, or 500mA per bay in standard mode, when all 4 slots are used at once.
Q: Will 21700 batteries fit properly in the UMS4? A: Yes. The UMS4's bays and spring-loaded contacts are sized to accommodate 21700 cells like the 50E without any adapter.
Q: How do I know if a 50E battery is degraded? A: The UMS4's LCD display shows battery health as "Good" or "Poor" along with internal resistance readings, making it easy to spot cells that have aged or lost performance.
Q: Can I power the UMS4 with a power bank while traveling? A: Yes. The UMS4 has a USB-C input and works with wall adapters, power banks, and solar panels.
Q: What's in the box? A: 4 EVE INR21700-50E batteries, 1 NITECORE UMS4 charger, a USB-C charging cable, and a user manual.
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.
