NITECORE UI2 USB-C Dual-Slot Portable Li-ion Battery Charger | Smart CC/CV Charging, Compatible with 20700/21700
Description
USB-C Dual-Slot Portable Li-ion Battery Charger
Broad Compatibility · Smart CC/CV Charging · 1000mA per Bay · Multiple Safety Protections
Key Features at a Glance
| Feature | Description |
|---|---|
| USB-C Input | Compatible with any 5V power bank, solar panel, or USB adapter — charge anywhere, anytime |
| Automatic CC/CV Charging Mode | Intelligently selects the most suitable charging mode (constant current / constant voltage) |
| Independent Dual-Bay Control | Each of the 2 bays charges independently without affecting the other |
| Trickle Charging | Automatically switches to trickle mode when battery voltage is below 2.9V, protecting the battery and extending its lifespan |
| Over-Discharge Battery Activation | Automatically detects and reactivates batteries that have over-discharged due to storage or improper use (for protected Li-ion cells) |
| Multiple Safety Protections | Reverse-polarity/short-circuit protection, intelligent temperature control, and overcharge protection — four layers of safety |
| Lightweight & Portable | Just 79.5g, 125.5 × 59.5 × 32.1mm — easy to carry anywhere outdoors |
| Fire-Retardant Housing | Built with PC fire-retardant material to handle demanding outdoor charging environments |
Broad Compatibility for 3.6V/3.7V Li-ion Batteries
Charges 20700 and 21700 cells, along with the following battery models:
10340, 10350, 10440, 10500, 12340, 12500, 12650, 13450, 13500, 13650, 14430, 14500, 14650, 16500, 16340 (RCR123), 16650, 17350, 17500, 17650, 17670, 18350, 18490, 18500, 18650, 20700, 21700, 22500, 22650, 25500, 26500, 26650
Automatic CC/CV Charging Mode
The UI2 intelligently selects the most suitable charging mode for each battery, switching flexibly between constant current and constant voltage to balance charging efficiency with battery safety.
Up to 1000mA per Bay
Supports trickle charging to effectively protect batteries and extend their lifespan.
- When a battery with voltage below 2.9V is inserted, the charger automatically enters trickle charging mode at 100mA
- When a battery with voltage above 2.9V is inserted, the charger switches to standard charging mode with a maximum current of 1000mA
Clear Charge-Level Display
Built-in indicator lights let you check battery charge level and charging status at a glance, in real time.
Over-Discharge Battery Activation
If a battery has over-discharged due to storage or improper use, the UI2 automatically detects and reactivates it, bringing "dormant" batteries back to life. (This feature applies to protected Li-ion cells.)
Multiple Protections for Safe Charging
- Reverse-Polarity & Short-Circuit Protection: If a battery fault or short circuit occurs, all three indicator lights flash to alert the user
- Fully Automatic Intelligent Temperature Control: When ambient temperature rises too high, the UI2 automatically adjusts current to protect both the charger and the battery
- Overcharge Protection: When a battery is fully charged, all three indicator lights turn solid and charging automatically stops
Built with PC Fire-Retardant Material
Premium materials ensure safety, letting you charge confidently in complex and variable outdoor environments.
Certified for Peace of Mind
CE and FCC certified for guaranteed quality.
Lightweight & Portable, Charge Anywhere
- Dimensions: 125.5mm × 59.5mm × 32.1mm
- Weight: 79.5g
Compact and lightweight — slips easily into a backpack or pocket for hassle-free outdoor carry.
Specifications
| Item | Spec |
|---|---|
| Model | UI2 |
| Input | DC 5V/2A 10W |
| Output Voltage | 4.2V±1% |
| Output Current | 1000mA×2 (max) |
| Compatible Batteries | Li-ion/IMR: 10340, 10350, 10440, 10500, 12340, 12500, 12650, 13450, 13500, 13650, 14430, 14500, 14650, 16500, 16340(RCR123), 16650, 17350, 17500, 17650, 17670, 18350, 18490, 18500, 18650, 20700, 21700, 22500, 22650, 25500, 26500, 26650 |
| Dimensions | 125.5mm × 59.5mm × 32.1mm |
| Weight | 79.5g |
FAQ
Q1: Which battery types are compatible with the NITECORE UI2?
A: The NITECORE UI2 offers broad compatibility for all 3.6V/3.7V Li-ion and IMR batteries. Supported sizes include: 10440, 14500, 16340 (RCR123), 18350, 18490, 18500, 18650, 20700, 21700, 22500, 22650, 25500, 26500, 26650, and more.
Q2: Does it use a USB-C port, and how can I power it?
A: Yes, the UI2 features a standard USB-C input. It can be powered by any 5V/2A (10W) USB wall adapter, power bank, solar panel, or car USB port. This makes it incredibly portable and perfect for outdoor or travel charging.
Q3: What is the charging speed? Can both slots charge at max speed simultaneously?
A: The UI2 provides a maximum output of 1000mA (1A) per slot. The two bays are fully independent, meaning both bays can charge simultaneously at up to 1A without affecting each other. If a battery voltage is below 2.9V, it will automatically enter a 100mA trickle charge mode to protect the cell.
Q4: Can the UI2 revive over-discharged batteries?
A: Yes, in most cases. The UI2 features an over-discharge battery activation function. When it detects a battery that has been over-discharged due to long-term storage or improper use, it automatically attempts to reactivate the cell. (Note: This applies to protected Li-ion cells).
Q5: How do I know when the battery is fully charged?
A: The UI2 features a clear LED indicator. When the battery is charging, the light will flash. Once the battery reaches the full 4.2V charge, the indicator light will stay solid (stop flashing), and the charger will automatically stop charging to prevent overcharging.
Important Safety Notice:
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Always use a 5V/2A or higher USB power adapter for optimal performance.
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Do not attempt to charge non-rechargeable batteries (e.g., alkaline) or damaged batteries that cannot be activated below 2.9V.
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During charging, place the charger in a well-ventilated area, away from high temperatures and flammable materials.
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
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Security
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.