Model: #OP4050A

4.5 | 470 Reviews
Compatible with all RYOBI 40V Lithium tools and chargers, the 40V 5.0 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 5.0 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: 5.0
  • Cell Type: Lithium-ion
  • Compatibility: All RYOBI 40V Lithium Tools & Chargers
  • Weight: 4 lbs.
  • Warranty: 3 Year Limited


  • 40V 5.0 AH Lithium-ion Battery
  • Operator's Manual


40V 5AH LITHIUM-ION BATTERY is rated 4.5 out of 5 by 463.
Rated 5 out of 5 by from Great Products After four complete cuts of my medium size yard. My 40V /5ah continues to impress me. After the mower use I put the same battery on my Ryobi trimmer and finish off the job! Oh Yeah. After that, I blow off the sidewalk and driveway with my 40V blower. When done I still have enough battery life to do even more. Impressive to say the least. One piece of advice. I store my three 40V Ryobi batteries in the house, not in the garage. Florida heat can really harm any kind of battery. My oldest battery is close to 3 years old and stills performs as it did "out of the box". I could not be happier with my Ryobi tools (4) and batteries (3)!
Date published: 2018-04-09
Rated 1 out of 5 by from Battery charging Bought this 40 volt a couple of years ago and as the years went on the Batter has failed or decreased in charging to a point that it eventually will not charge at all. Looks to me that I might be the first customer here at this site with a negative review. If you want to see more bad reviews go to the Home Depot reviews and you will find many more like mine. These batteries are too expensive to having to keep buying at 99$ with a 3 year warranty and sometime less. Really wish Ryobi could do something about this. Many pieces of equipment use this and the 18 volt which I do not seem to have a problem with. Hope this gets to the right people because the tools are very good. The Batteries not so much.
Date published: 2017-04-25
Rated 4 out of 5 by from Battery Problems - Excellent Warrantee & Service I purchased three of the tools that use these batteries - love the tools (edger, weed eater and blower) but the batteries have been an issue. So far, both batteries received with the tools failed within a matter or weeks. The good news is that Home Depot and Ryobi backed these failures 100% and made good on the 3-year warrantees. Both batteries and their chargers were promptly replaced. Having spoken to Ryobi's excellent customer service, I am hopeful that the battery issues have been fixed. Its been several weeks now, and the replacement batteries and chargers seem to be holding up just fine.
Date published: 2017-06-11
Rated 5 out of 5 by from Green means go! This battery is pretty sweet. However, I did have to exchange the one that was included with my 40V 20" Lawnmower kit. According to Ryobi OPE customer support the one included in my kit was defective and HD exchanged it for a new one no questions asked. The battery is powerful and the run time aligns with the spec sheet when powering the lawnmower. I was able to run the mower for about 40ish minutes, then switched to the string trimmer for about 10 min and still one indicator light illuminated. It is powerful and gets the job done but I do wish it charged faster. If you plan on mowing first thing Saturday morning, I suggest you charge it the night before. It took a LONG time, hour +.
Date published: 2017-04-25
Rated 2 out of 5 by from Great Battery if you can get one that works Along with a 20" mower I bought a second 5AH battery , and initially both batteries were defective causing me to return the mower for a replacement. The second mower had a good battery and without a doubt it's a very good tool, however the spare battery would quit after ~1minute even while showing full charge. The 1st warranty replacement did the same , I'm waiting on a 2nd replacement now as well as a replacement charger. ( all though the good battery has no issue with the existing charger) If I had gotten good batteries, this review would have been a 5+.
Date published: 2017-06-07
Rated 5 out of 5 by from Good as gas! Been using this battery for over a month to mow my mid-size yard, it holds a good charge even when the grass is fairly tall. It has no problem providing enough juice to cut through the thicker areas of grass. I can easily mow my front yard and start on my back yard without worry of the battery going dead. Typically, I can use two of these batteries to mow, weed eat, and blow. They charge quick and the charge indicator button is an easy way to check how much time you have left before needing to swap out. I've always swore by gas law equipment, but the convenience and ease of using these batteries has been well worth the switch to electric!
Date published: 2018-09-11
Rated 5 out of 5 by from EXCELLENT CHARGE RETENTION I got 40V 5.0 AH battery 6 weeks ago after the original 40V 2.6 AH battery couldn't get me through the weed trimming and blowing the clippings off the driveway, patio and sidewalks without needing recharged. I have used the new battery twice weekly during this time and I am very impressed with the 40V 5.0 AH battery because now I can trim for several hundred feet - plus blow all the clippings and still have half of the charge left in the battery ! Also, the power of this battery rivals any gas powered string trimmer I've ever owned. I suggest Ryobi should make the 40V 5.0 AH battery the standard battery included with their line of 40V tools - it's that good !
Date published: 2018-09-22
Rated 5 out of 5 by from 40V 5.0 AH Lith-Ion Battery I am a senior citizen, live in the South where it gets unbearably hot in the summer months. As I have moved all my shop and yard tools to the RYOBI systems, I have discovered that battery-powered tools contribute to a healthier old age posture! Being a work demon, I have always went full-tilt boogie on a job until it was done. Dow-un heah, the Palmetto State's summer heat, kin absolutely kill ya, but I find that now I work until my battery runs out, then I pour some lemonade, have some gingerbread and set a spell. I have back-up batteries, but the life of one 40v battery in my mower or trimmer is a good warning sign to this ol' timer that it's to take a breather.
Date published: 2017-10-17
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