40V 4AH Lithium-ion Battery

Model: #OP4040A1

4.7 | 634 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 632.
Rated 5 out of 5 by from Small and Powerful Great battery!!! Easy to store when not in use, and powerful enough to complete a job without recharging, Am really pleased with Ryobi quality.
Date published: 2022-11-17
Rated 5 out of 5 by from Good lasting battery I bought this as an extra battery for my ryobi tools. It keeps a good charge on it
Date published: 2022-11-06
Rated 5 out of 5 by from Great Holds charge. When used in Pole saw or trimmer it has more then enough power to complete the task.
Date published: 2022-10-31
Rated 4 out of 5 by from Solid performance Good battery, decent life. Chain saws eat it quickly, though...
Date published: 2022-10-24
Rated 5 out of 5 by from Great Battery! Very versatile and powerful, charge lasts a long time!
Date published: 2022-10-23
Rated 5 out of 5 by from Excellent battery life I bought this to avoid using gas, and was worried if it was going to have enough power to do my while yard, as I am on 1/3 of an acre, but the battery lasted the whole yard and still had power left over!
Date published: 2022-10-22
Rated 5 out of 5 by from Nothing better than Original I bought my lawn mower in 2016, so the battery had run its course, I bought a generic battery and the lawn mower had hardly any power or it would not last as long as before, so I thought my lawn mower was also bad (because it was old) and I use it very often, I was about to buy a new one when I decided to just buy an original battery and Yes best decision ever... Lawn mower is working like the day I bought it I can doo my whole yard with one charge and still 2 lights remain on the battery, Nothing beats Original I recommend this battery 100%
Date published: 2022-10-21
Rated 5 out of 5 by from Good performer Good performer And can be used on all my Ryobi products!
Date published: 2022-10-05
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