40V 4AH Lithium-ion Battery

Model: #OP4040A1

4.7 | 673 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 671.
Rated 5 out of 5 by from Excellent Batyery Excellent battery. Holds charge well. Always reliable for all my Ryobi tools.
Date published: 2023-05-22
Rated 1 out of 5 by from Out of box failure I bought this yesterday and it is dead on arrival!
Date published: 2023-05-17
Rated 5 out of 5 by from Good battery Good battery. Works well and has a good amount of runtime.
Date published: 2023-05-12
Rated 3 out of 5 by from Short life Died in one season… Approximately 12 uses… But the company stood by it and sent me a new one… this is the second time this has happened … product is descent but the batteries don’t last… The company is at least willing to stand by it though.
Date published: 2023-05-10
Rated 5 out of 5 by from Works great It works great and I no longer have to mix gas and oil together
Date published: 2023-05-07
Rated 5 out of 5 by from Excellent run time I have 3 batteries and they give great life performance and recharge quickly.
Date published: 2023-05-07
Rated 2 out of 5 by from Great tools, garbage batteries. I and my wife have bought 2 40v 14" chainsaws, a 40v weedeater and a 40v blower and every one of them has had the battery fail in less than 6 months 2 of the replacement batteries have also failed.. The tools are terrific but the batteries are garbage! I bought the blower with battery for $179.99 because it was cheaper to get the blower than just a battery for $179/99 at Home Depot. ! I have had to call
Date published: 2023-04-24
Rated 4 out of 5 by from Works with my Lawnmower. I got this with a trimmer so I'd have an extra battery that works with my Lawnmower. It worked okay but was surprised how it did not last as long as expected. I used for 10 minutes on the trimmer than used on the mower after my 6ah battery died. It lasted maybe 20 minutes run time. I was surprised how much difference there is between the 4 & 6 ah batteries. My 6 ah battery lasted an hour run time last year, but it was new. This year It ran maybe 45 minutes.
Date published: 2023-04-20
Rated 3 out of 5 by from Too long for my mower I bought this to use in my tools and it works fine in my blower and trimmer. However, it was too long to fit in my mower. It’s about a half inch longer than the battery that came with my mower.
Date published: 2023-04-18
Rated 1 out of 5 by from Ryobi 40 v batteries I have two which I bought two 14" Chainsaws. One does not work after 6 months and 5 hours of use the other after 8 months last 20 minutes. Don't buy this product. There are others with better battery life.
Date published: 2023-04-16
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