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DEWALT FlexVolt 9.0Ah Battery (DCB609) vs Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

Head-to-head spec comparison to help you pick the right battery for your needs.

DeWalt

$152.49

Buy on Amazon
vs

Milwaukee

$67.99

Buy on Amazon
Deciding between a genuine pack and a cheaper aftermarket one? Read our honest genuine vs aftermarket batteries guide.Read the guide →

Spec Winner

Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

Wins on 3 of 4 spec categories

Spec-by-Spec Comparison

SpecDEWALT FlexVolt 9.0Ah Battery (DCB609)Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)
PlatformFlexVoltM18
Voltage20V/60V MAX18V
Capacity9 Ah5 Ah
Typehigh-outputhigh-output
Genuine OEMYesYes
Fuel GaugeNoNo
Warranty3 years5 years
Price$152.49$67.99
Rating8.7/108.8/10
Buy on AmazonBuy on Amazon

Pros & Cons

DEWALT FlexVolt 9.0Ah Battery (DCB609)

Pros

  • Genuine DEWALT FlexVolt pack backed by DEWALT's 3-year warranty
  • FlexVolt design auto-switches between 20V and 60V MAX tools
  • High capacity suited to demanding FlexVolt tools like table saws and mowers

Cons

  • Premium price point relative to standard 20V MAX packs
  • More capacity than needed for light-duty 20V MAX tools
  • No fuel gauge readout mentioned for this pack

Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

Pros

  • Genuine Milwaukee M18 pack backed by Milwaukee's 5-year warranty
  • Drops straight into any M18 tool — no adapters, no guesswork
  • 5.0Ah capacity gives solid runtime for daily-use M18 tools
  • REDLITHIUM cell design is Milwaukee's own in-house spec

Cons

  • No onboard fuel gauge — can't check remaining charge at a glance
  • Costs more than aftermarket M18-compatible packs
  • Only fits the M18 platform, not M12 or other brands

Our Verdicts

DEWALT FlexVolt 9.0Ah Battery (DCB609)

The DCB609 is DEWALT's genuine high-capacity FlexVolt pack — built for the cross-platform 20V/60V lineup, at a real premium over standard 20V MAX batteries.

Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

A genuine Milwaukee M18 pack is the safe first buy for anyone standardized on the M18 platform — real Milwaukee chemistry and the full manufacturer warranty, not a third-party guess.

DEWALT FlexVolt 9.0Ah Battery (DCB609)

$152.49

Buy on Amazon

Milwaukee M18 REDLITHIUM 5.0Ah Battery (48-11-1850)

$67.99

Buy on Amazon

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