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Nitecore F21i iSeries Battery Charger and USB-C Powerbank
NITECORE F21i iSeries Battery Charger and USB-C Powerbank

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Price: $19.95

Availability: Usually Ships in 24 Hours
Product Code: CHG-NITE-F21I

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1x Nitecore NL2150HPi 5000mAh Battery [Add $25.95]



  • Multiple protection safeguards
  • Ultra compact and lightweight
  • EPDM elastic band
  • Touch sensor power display

Included in the Box

  • F21i
  • USB-C charging cable

iSeries Battery Charger & Powerbank

The Nitecore F21i turns your iSeries battery such as NL21500HPi into a minimalist battery charger and power bank. The F21i features a USB-C port that functions both as a battery charger when connected to a power adapter and as a power bank when connected to a device. The 3-dot blue indicator beneath the USB port flashes to indicate the charging progress. Supporting Quick Charge and Power Delivery (QC, PD) protocols, F21i delivers an incredible 18W of fast charging output. The F21i is a mini multi-functional battery charger and power bank as well as a must-have backup battery and accessory for any iSeries tactical flashlight.

Tough and Light

The F21i is ultra-compact, durable and safe to use. It is about 2 inches long when stowed away and only 4 inches long when fully stretched. Its rigid battery cap is made from fire retardant polycarbonate. It also comes with the same comprehensive safeguards as the other Nitecore chargers: overcharge protection, overcurrent protection, over-discharge protection, short-circuit protection, thermal protection, and overvoltage protection. Always be prepared by pairing a F21i with a iSeries battery for emergency power.


Input USB-C:5V⎓2A / 9V⎓2A
Output Battery:4.2V⎓4A (MAX) USB-C:5V⎓2.4A / 9V⎓2A / 12V⎓1.5A
Dimensions L-4.43"xW-1.08"xH-1.08"
Weight 0.78oz

Compatible Power Sources

Nitecore 21700 i Series 21700 3.6 Y (Recommended)

*Battery Not Included
Nitecore F21i
Average Rating: Average Rating: 5 of 5 5 of 5 Total Reviews: 12 Write a review »

  0 of 0 people found the following review helpful:
5 of 5 State-of-the-art Battery Charger. January 23, 2022
Reviewer: Jerry Davis from Lemooree, CA United States  
This Charger takes all Battery's that you have. It has four slots, Two for fast charging and two for regular charging. But it is a Hi-Tech charger. I am so glad I purchased it. Everyone that owns a Nitecore flashlight needs this charger.

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  0 of 0 people found the following review helpful:
5 of 5 Nitecore Delivers as Advertised January 7, 2022
Reviewer: Blake Hendrickson  
Just added these components to my growing collection of Nitecore resources.

Useful for both tactical and practical situations.

The battery bank helps out in a low phone scenario as well as powering digital cameras and audio recorders while capturing media outside of the studio.

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  0 of 0 people found the following review helpful:
5 of 5 Great compact power bank December 29, 2021
Reviewer: Mike United States from PA  
The F21i is a good power bank that can be expanded by ordering more batteries and is very compact

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  0 of 0 people found the following review helpful:
5 of 5 Neat product December 18, 2021
Reviewer: RobertRobert Honeycutt from MadisonTenneessee, USA, TN United States  
This charger/power bank is a must have if you already use Nitecore products that use i series battery. Very small convenient charger and power bank functions work very well. Thanks Nitecore!

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  2 of 2 people found the following review helpful:
5 of 5 F21i lives up to its specifications! October 22, 2021
Reviewer: Jim from Texas  
I bought the F21i as the LIGHTEST 5000 mAh powerbank that supported BOTH max 18W output AND max 18 input which has been commonly called "fast charging."  My F21i weighs 99 g with its battery and lives up to its specs as I personally tested with a USB multimeter and a USB load tester.  I will remind readers that the F21i has only a single USB-C port, so one will need adapters for devices that have USB-A and microUSB connectors, but the F21i does the proper handshaking for low-power devices.  As a bonus the F21i flawlessly charges with power from a small solar panel even if power cuts out intermittently due to shadows from clouds, trees, and other sun blockers.

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