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FLEX 24V 8.0Ah Lithium-Ion Battery - FX0221-1, Grey/Black

  • Based on 103 reviews
Condition: New
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$219.99 Why this price?

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Availability: In Stock.
Fulfilled by Amazon

Arrives Mar 12 – Mar 26
Order within 23 minutes
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Style: 8.0Ah Lithium-Ion


Features

  • THE FLEX ADVANTAGE - 24V Lithium Technology
  • THERMA-TECH HEAT MANAGEMENT - Innovative cooling system minimizes heat for 25% longer runtime
  • POWER IQ - Intelligent power management monitors and optimizes the cells for overload protection and higher power
  • DROP, DUST, AND WATER RESISTANT - Engineered with a shock-resistant design and sealed electronics
  • PATENTED DUAL-SIDED FUEL GAUGE - Quickly view battery charge from multiple angles
  • FASTER CHARGING - Up to 50% faster charging - 160W Fast Charger Charge Time: 90 Mins, 280W Rapid Charger Charge Time: 50 Mins
  • BATTERY LOCK SYSTEM - Durable design prevents accidental disconnection during recharging
  • FLEX 24V CROSS-COMPATIBILITY - Compatible with all FLEX 24V batteries, chargers, and tools
  • FLEX 5-YEAR LIMITED WARRANTY - Register your new FLEX tool, battery, or charger within 30 days of purchase to receive a 5-year limited warranty; 3-year limited warranty without registration

Description

The FLEX 24V Lithium battery platform brings power output to the next level. It combines intelligent battery management with THERMA-TECH™ cooling technology to deliver a driving force that's up to 20% higher than anything you've already seen out there.

Number of Batteries: 1 Lithium Ion batteries required. (included)


Brand: FLEX


Battery Cell Composition: Lithium Ion


Battery Capacity: 8 Amp Hours


Unit Count: 1.0 Count


Manufacturer: ‎FLEX


Part Number: ‎FX0221-1


Item Weight: ‎3 pounds


Product Dimensions: ‎5.6 x 3.5 x 2.8 inches


Item model number: ‎FX0221-1


Batteries: ‎1 Lithium Ion batteries required. (included)


Size: ‎8.0Ah


Color: ‎Grey/Black


Style: ‎8.0Ah Lithium-Ion


Finish: ‎Brushed


Material: ‎Blend


Pattern: ‎Solid


Shape: ‎Rectangular


Power Source: ‎hand_powered


Voltage: ‎24 Volts


Item Package Quantity: ‎1


Included Components: ‎8.0Ah Lithium-Ion Battery


Batteries Included?: ‎Yes


Batteries Required?: ‎No


Battery Cell Type: ‎Lithium Ion


Battery Capacity: ‎8 Amp Hours


Warranty Description: ‎Limited Lifetime Warranty with Registration


Date First Available: January 1, 2024


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Mar 12 – Mar 26

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

  • Klarna Financing
  • Affirm Pay in 4
  • Affirm Financing
  • Afterpay Financing
  • PayTomorrow Financing
  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Top Amazon Reviews


  • Battery works great
Style: 8.0Ah Lithium-Ion
Good quality battery
Reviewed in the United States on January 4, 2026 by Tim

  • Great for high powered tools.
Style: 12.0Ah Lithium-Ion
This battery is amazing. It feels like it lasts forever and is my go to battery for my higher powered tools like the grinder and circular saw. It is heavy and bulky but it's worth it for the high power tools compared to swapping the smaller ones nonstop.
Reviewed in the United States on October 23, 2025 by Timothy

  • Awesome battery
Style: 8.0Ah Lithium-Ion
Awesome battery, I want to purchase more!!! I am building my own home. Dang good batteries with a very long charge! They last all day long.
Reviewed in the United States on January 8, 2026 by Amazon Customer

  • Good deal
Style: 8.0Ah Lithium-Ion
Very well priced, works great on my wet or dry vacuum. Lasts over an hour of continues. Good deal for me.
Reviewed in the United States on August 28, 2025 by MS

  • Flex
Style: Lithium-Ion Starter Kit (5.0Ah + 160W)
Build like a tank and powerful
Reviewed in the United States on January 4, 2026 by Ali Peters

  • Flex
Style: 8.0Ah Lithium-Ion
Good Value and strong battery!
Reviewed in the United States on September 27, 2025 by woodchucker

  • Nice
Style: 12.0Ah Lithium-Ion
Great battery get what you pay for
Reviewed in the United States on December 26, 2025 by Kory Arceneaux

  • Battery leakage
Style: 8.0Ah Lithium-Ion
There was black gunk running out of the battery and was inside the package as well. The battery had the same issue the batteries that came with the Flex tools. I have flex tools and no battery that will function. I have since changed tool brands that seem to know how to make a battery. The tools were great, the battery had a lot to be desired. ... show more
Reviewed in the United States on October 21, 2025 by Charlie

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