40V 4AH Lithium-ion Battery

Model: #OP4040A1

4.7 | 649 Reviews
Compatible with all RYOBI 40V Lithium tools and chargers, the 40V 4.0 AH Lithium-ion Battery is the perfect addition to your RYOBI 40V tool collection. It's lithium-ion cells deliver fade-free performance from start to finish. The convenient on-board battery life indicator keeps you informed while you're out in the yard tackling your landscaping jobs. The 40V 4.0 AH Lithium-ion Battery's extra cell capacity is perfect for higher output tools like 40V mowers, blowers and chain saws. RYOBI 40V Lithium surrenders nothing but gas.


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This product is covered by a 3-year limited warranty.

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  • Voltage: 40
  • Amp Hours: 4.0
  • Cell Type: Lithium-ion
  • Compatibility: All RYOBI 40V Lithium Tools & Chargers
  • Weight: 4 lbs.
  • Warranty: 3 Year Limited


  • 40V 4.0 AH Lithium-ion Battery
  • Operator's Manual


40V 4AH Lithium-ion Battery
40V 4AH BATTERY is rated 4.7 out of 5 by 647.
Rated 5 out of 5 by from User friendly Very happy easy use me being a woman weed eater blower and vac
Date published: 2023-01-25
Rated 2 out of 5 by from Unreliable battery life Battery damages very quickly. I have two Ryobi equipments that use this 40v battery and had to ask for warranty on both batteries with less tha than 20 hours of use.
Date published: 2023-01-22
Rated 5 out of 5 by from Awesome Batteries I bought my mower about 3 weeks ago. The batteries are AWESOME!!! The power they put out REALLY SURPRISED ME!!! Talk about the "WOW" factor, this is Next Level !!! I have already mowed my yard twice and used only 1 of the 2 batteries.
Date published: 2023-01-17
Rated 5 out of 5 by from HRH Plano Have been using for several weeks now. Great product!
Date published: 2023-01-11
Rated 5 out of 5 by from Good Strong Battery received this as a Christmas gift - have had the opportunity to use it several times since - has very good battery life and charges a lot quicker than some of my older models
Date published: 2023-01-09
Rated 5 out of 5 by from A great battery! A great, long-lasting battery that fits a lot of the Ryobi products. I do recommend!
Date published: 2023-01-09
Rated 5 out of 5 by from Easy to charge Using for chainsaw and weed whip around my farm daily
Date published: 2022-12-29
Rated 5 out of 5 by from power to spare I have kept with the Ryobi tool platform due to the interchangeability of the tools with the battery, I have extended the platform by going 40 volt, my weedeater and now my chainsaw both use the 40 volt battery system, and the batteries last, soooo much easier than mixing oil, or pulling a rope on a tool that has been stored through winterclick them in and go!
Date published: 2022-12-19
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