Nitecore UI2 – Dual-Slot Portable USB Li-ion Battery Charger
Powerful and compact, the Nitecore UI2 is a dual-slot portable USB lithium-ion battery charger that reaches a maximum charging current of 800mA per slot and accepts 18650, 18350, 20700, 21700 and dozens of other Li-ion and IMR cell sizes. Two independent bays mean you can top off a pair of 18650s at once. At 2.8 oz and 4.94" long, the Nitecore UI2 still fits in the palm of your hand.
Its USB input works with wall adapters, power banks, solar panels and car chargers, making the Nitecore UI2 a practical field charger for camping, overlanding and emergency kits as well as a compact everyday charger for 18650 flashlight users.
Key Features
- Dual-slot portable USB Li-ion battery charger
- Maximum charging current of 800mA per slot
- Intelligent charging mode selection (constant current and constant voltage)
- Power indicator shows real-time battery level and charging status
- Safeguards against reverse polarity, overcharging and overheating
- Charges large-format cells including 20700 and 21700
- Lightweight and portable for outdoor charging
Specifications
| Model |
Nitecore UI2 |
| Slots |
2 |
| Input |
DC 5V/2A 10W (USB) |
| Output Voltage |
4.2V ±1% |
| Output Current |
800mA x 2 (max) |
| Compatible With |
Li-ion / IMR: 10340, 10350, 10440, 10500, 12340, 12500, 12650, 13450, 13500, 13650, 14430, 14500, 14650, 16340 (RCR123), 16500, 16650, 17350, 17500, 17650, 17670, 18350, 18490, 18500, 18650, 20700, 21700, 22500, 22650, 25500, 26500, 26650 |
| Dimensions |
L-4.94" x W-2.34" x H-1.26" |
| Weight |
2.8 oz |
| In the Box |
1 x Nitecore UI2 charger, 1 x USB charging cable |
Frequently Asked Questions
What batteries does the Nitecore UI2 charge?
The Nitecore UI2 charges rechargeable Li-ion and IMR cells including 18650, 21700, 20700, 18350, 16340 (RCR123), 14500, 26650 and more than two dozen other sizes. It is a Li-ion charger only — do not use the Nitecore UI2 with NiMH or alkaline batteries.
Can the Nitecore UI2 charge two batteries at the same time?
Yes. The Nitecore UI2 has two independent charging bays, each delivering up to 800mA, so a pair of 18650 cells charges simultaneously at full current rather than sharing one supply.
How fast does the Nitecore UI2 charge?
Each slot on the Nitecore UI2 delivers up to 800mA at 4.2V ±1%. On a 3400mAh 18650 that is roughly four to five hours from empty, with the charger switching automatically between constant-current and constant-voltage modes.
Is the Nitecore UI2 safe to leave charging?
Yes. The Nitecore UI2 protects against reverse polarity, overcharging and overheating and terminates the charge automatically when each cell is full. As with any lithium charger, use it on a hard non-flammable surface.
Can you power the Nitecore UI2 from a power bank or solar panel?
Yes. The Nitecore UI2 draws DC 5V/2A over USB, so it runs from a power bank, solar panel, car adapter, laptop port or wall adapter — which is what makes the Nitecore UI2 useful for camping, travel and emergency kits.
How big is the Nitecore UI2?
The Nitecore UI2 measures L-4.94" x W-2.34" x H-1.26" and weighs 2.8 oz — a little wider than the single-slot Nitecore UI1 to make room for the second bay, but still pocketable.
Where can I buy the Nitecore UI2?
You can buy the Nitecore UI2 dual-slot USB Li-ion battery charger here at Going Gear, an authorized Nitecore dealer, so you receive genuine Nitecore stock backed by the manufacturer's warranty.
