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DEWALT FlexVolt 9.0Ah Battery (DCB609) vs RYOBI 40V Lithium-Ion 4Ah High Capacity Battery

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

DeWalt

$152.49

Buy on Amazon
vs

Ryobi

$104.99

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

DEWALT FlexVolt 9.0Ah Battery (DCB609)

Wins on 2 of 3 spec categories

Spec-by-Spec Comparison

SpecDEWALT FlexVolt 9.0Ah Battery (DCB609)RYOBI 40V Lithium-Ion 4Ah High Capacity Battery
PlatformFlexVolt40V
Voltage20V/60V MAX40V MAX
Capacity9 Ah4 Ah
Typehigh-outputhigh-output
Genuine OEMYesYes
Fuel GaugeNoNo
Warranty3 years3 years
Price$152.49$104.99
Rating8.7/108.4/10
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

RYOBI 40V Lithium-Ion 4Ah High Capacity Battery

Pros

  • Genuine RYOBI 40V pack backed by RYOBI's 3-year warranty
  • 4Ah capacity suits RYOBI's outdoor power equipment lineup — mowers, trimmers, blowers
  • Fits the full RYOBI 40V platform

Cons

  • Listed as low stock at the time of this write-up — availability can be inconsistent
  • Mid-range price relative to smaller-capacity 40V packs
  • Only compatible with 40V tools, not ONE+ 18V

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.

RYOBI 40V Lithium-Ion 4Ah High Capacity Battery

A genuine RYOBI 40V pack for the outdoor-tool side of the lineup — solid capacity for mowers and trimmers, though stock availability has been inconsistent.

DEWALT FlexVolt 9.0Ah Battery (DCB609)

$152.49

Buy on Amazon

RYOBI 40V Lithium-Ion 4Ah High Capacity Battery

$104.99

Buy on Amazon

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