Model: #OP4050A

4.5 | 552 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 BATTERY is rated 4.5 out of 5 by 551.
Rated 4 out of 5 by from Good Battery I bought this to get extra power for my chainsaw!!
Date published: 2023-11-26
Rated 5 out of 5 by from 40 volt battery review. I am very happy with this batteries performance.
Date published: 2023-10-13
Rated 1 out of 5 by from Junk batterys I got my mower last yr and the batterys are junk so do you replace them 2 battery op40501 Iam 69 and I can't keep buying bayyerys all the time I,have all kinds of ryobi tools I've had for a while. So can I get them replaced or do I go to a different brand.
Date published: 2023-10-06
Rated 3 out of 5 by from Make sure it fits Purchased 5v to replace one that no longer would charge (past warranty). Works fine but is a slightly different shape then previous battery. Cover on lawnmower will not fully close when the new battery is used. They say all 40v batteries work with all tools but that is not quite true. I have a 6 amp battery that does not fit in my blower.
Date published: 2023-09-22
Rated 5 out of 5 by from My Tool great product will buy more. so many usages and compact.
Date published: 2023-09-19
Rated 2 out of 5 by from Not as durable as older batteries . This was a replacement for a battery that stopped charging after less than 3 years. I have older model batteries that are still accepting charge with no problems.
Date published: 2023-08-20
Rated 2 out of 5 by from The plastic holding front of the battery cracked This battery appears to operate correctly but there’s a large crack in the plastic that’s holding the front of the battery to the clip. Not exactly sure how that happened especially since the battery appears to be pretty durable. This was one of my favorite batteries, now it feel unsafe to use. Attaching pictures for reference.
Date published: 2023-08-04
Rated 3 out of 5 by from Affordable and available! I would like to know why it’s cheaper to buy a tool with battery and charger? It seems the price would be significantly lower than having to buy another tool just so the battery isn’t outrageously priced. Comparatively, my ryobi chargers and batteries seem to give out super quick compared to my dewalt batteries. 20v versus 40v though. I wish my ryobi tools had a smaller much lighter weight battery. It would be easier for a woman to use or hold for long periods of time. I also wish there were a closer repair place to where I live instead of having to drive over an hour to get replacement batteries and chargers. My positive about my ryobi tools is that they are much more affordable for me than the higher end brands. And they have a great selection of tools and attachments, etc. Good ryobi tool specials. Would like more lawn type tools on special with battery packs .
Date published: 2023-07-28
Rated 1 out of 5 by from Does not fit older model chainsaw. I bought this battery for an older model Ryobi chainsaw and it will not physically fit into the battery compartment. I spent almost as much for this battery as I did for the chainsaw, and to have it not fit is very disappointing, to say the least.
Date published: 2023-07-13
Rated 1 out of 5 by from Two Died Right After Warranty Both this and my 4Ah died as soon as the warranty expired. I wouldn't be surprised if they are intentionally doing this with how they died extremely close to each other and after warranty time frame.
Date published: 2023-07-12
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