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WORX 4 Ah Lithium Ion (li-ion) Battery

20 Reviews
  • 4.0 Ah Lithium technology charges quickly and powers your cordless WORX tool through the entire job
  • Max Lithium batteries are lighter, more efficient, and charge with no memory effect
  • Recommended to use with WORX WA3742 20V Lithium charger, or WORX WA3868 20V Lithium quick charger


The WORX 20V 4.0 Ah max Lithium battery charges quickly and powers your cordless WORX tool through the entire job. Max Lithium batteries are lighter, more efficient, and charge with no memory effect. Includes an indicator system to quickly and easily determine how much battery life remains. Recommended to use with WORX WA3742 20V Lithium charger, or WORX WA3868 20V Lithium quick charger.
  • 4.0 Ah Lithium technology charges quickly and powers your cordless WORX tool through the entire job
  • Max Lithium batteries are lighter, more efficient, and charge with no memory effect
  • Recommended to use with WORX WA3742 20V Lithium charger, or WORX WA3868 20V Lithium quick charger
  • Great extra battery to have for WORX 18V or 20V Lithium tools
  • Includes indicator system for quick battery life review
Weight 1.48 lbs
Dimensions 6.5 × 3.54 × 9.65 in

Latest reviews

  1. Tierra

    I have had my Worx Trimmer for a few years now. Which I can’t go a day without. It’s absolutely amazing and gets the job done. My battery recently died on me and I needed a replacement quick. I visited the Worx webpage and notice they had a NEW 20v 4.0ah battery. Which provides 25% more runtime than the originally 20v battery can you say “AMAZING”? 1 battery and extra runtime is just what I needed. “YESSSSS”. I purchased and received my battery within a few days. Charged that bad boy up and tested it on my trimmer. Boy ol boy when I tell you I finished the job and still had power left in the battery actually shocked the heck out of me. One of the best accessories I purchased for my trimmer. One Happy Thrilled customer. You Guys At Worx Never Let Me Down.

  2. theMarmotGuy

    I bought a batch of Worx tools last month to do scheduled maintenance at properties where corded tools just “wouldn’t work”.

    So far I love the hedge-trimmer (WG261) and the bundled trimmer/blower package (WG155 & WG545). I’m less happy with today’s lawnmower purchase (WG761) as the fully-charged batteries died after mowing a little less than 3000 ft².

    My first question is: “in a pinch (as happened today), could I safely use two freshly charged 2 amp (WA3525) batteries to power my lawnmower (which takes the 4 amp WA3579) batteries through that final fifty feet that needed mowing?

    My second question is the converse: “can I hang a 4 amp battery on a 2 amp device without damaging either the device or the battery?”

    Thank you. So far…I love the ergonomics and workmanship of your tools.

  3. LGYC

    I bought the power washer with this battery included and used it a few times last summer. This April, I try to charge the battery and the Worx charger thinks it is fully charged (full green not full red) but the battery indicates one green light. No way to charge it even though the battery has been used only a few times.
    No apparent way to contact support either. Now I have a useless power washer without having to shell out money to get a new battery.

  4. Carlygrace

    I have several items and so I got the new 20, AH-MaxL Batteries that is awesome lets me finish the job in just a short time and easy changeable batteries snap off snap on and just minutes ready to use again! I would never go back to those endless cords draging them around the house down the side walks I just like my Worx great tools and great piece of work! I love the performance it gives! I love dove doing my yard work now and looks so great!

  5. Lawn robot owner

    Both extra batteries I additionally purchased overheat. The batteries have the same voltage but will not work. My landroid will leave the base then comes right back with 100 percent charge, then on the app it indicates the reason as battery is over temperature. When I take the battery out it was cool to the touch of my face. This happens only on my two additional batteries I purchased separately, my original battery works fine as far as I can tell.

  6. Suz11

    I have an older (7-8 years old) Words weed Wacker. The battery that came with it still works but the battery only lasts about 20 – 30 minutes Max.
    So I purchased this larger newer battery and so far it’s fantastic! Battery lasts almost an hour and my weed Wacker seems to have more power with this battery. It also fits and charges in the original charger. Enters and releases just lie it should.
    So, I am very glad I purchased it.

  7. Gem1

    Do you don’t have any collum or space where anyone can ask questions about your certain products? Just like Review and Questions & Answers in other merchandise products’s website now days. It looks you are too behind in web ads to give full info about your product. Sorry, I could”t remain to say this. Now I want to this 20V 4.0 AH MaxLithium Battery (WA3526) is come with its charger? Is WA3526 is compatible with charger WA3733?

  8. Granny54

    We bought this battery along with the 1 hr dbl charger, WOW what a time saver!! Not only does this battery last at least twice as long as the 20V 2.0Ah batteries, it charges just as quickly! Now we never run out of battery power! This last longer in the Blower we got also. So glad we found this!! Great product!! While it is slightly heavier than the smaller batteries, it isn’t enough so to cause any problems.

  9. Hetty

    I have been collecting Worx batteries since 2013. When I get a new battery, I date it and give each one an identification a b c etc. My 2013 battery still holds a charge and has decent run time. These new 4.0 Ah batteries have been very handy. Usually 2 charged batteries will work for all morning and at noon during lunch go on the charger, then with an hour charge be ready for all afternoon.

  10. cleod5

    We work our Worx products pretty hard, and need a little more power to get all the work done. The 20V Power Share 4.0 Ah Battery definitely helps with that issue. We used to have to switch out batteries before completing our tasks, but now, the battery out lasts us. It’s nice to be able to upgrade a product to fit the individual needs of each customer. Good job Development Team.

  11. Buddyv69

    I was really needing this battery to go with the other battery that i had so I could have enough juice to mow my yard. I have a total of 4 batteries to get the yard cut. I am very pleased with the run time on them they do last a while plus they stay charged once they get charged up. I would recommend Worx products to anyone without question or doubt. Very durable products!

  12. always ready to trim

    I bought my second 20V 4.0 battery to keep on hand when trimming. What a blessing to be able to continue trimming and not wait on charging. I charge one while trimming and then recharge the first one. While some might say one battery should last that is just not the case for me as I’m very OCD about weeds, edging etc.
    Just love my trimmer and my yard looks perfect!

  13. Monte Jr

    I bought this to supplement my supply of Worx equipment and I have been very satisfied with the power delivered through an extended cycle. This enables more efficient lawn work without having to stop and replenish power supply. Whether trimming grass, hedges, or powerwashing with my HydroShot this battery does the trick to keep me on the job so I can finish early!

  14. Cabj

    Great battery. This is a 2nd one I bought. So one can charge while I use other it’s easy to connect and disconnect.

  15. AnnRG

    Not sure what to do, I bought a trimmer brand spanking new from a retail store two days ago. I put battery on charge for approximately 24 hours until I used it today….I went about thirty feet and battery died…..???? I don’t know what to rate it as this is my first time using it! It worked really well and loved not being tethered to power cord……

  16. jagxjsv12

    tHIS 4.0 AH battery is perfect for 20v tools. I have 4 and 2 more coming that are included with the cordless mower just ordered. 6 batteries altogether will be more than enough to mow a large yard, trim hedges, blow sidewalk without charging. Every now and then you make a good purchase that does as advertised. This is certainly one of those purchases.

  17. BradQ

    Maybe because it is new, I had one on the leaf blower over the weekend. The blowing power felt stronger. The running time definitely felt more than 2X the 2.0Ah battery. I tried to deplete the battery, but eventually gave up after sweeping the front and backyard 2 times. Previously it typically take three 20V, 2.0Ah batteries to do the job. Love it.

  18. LadyHandyman

    It is well worth the money to purchase the higher power batteries. The 2.0 would only allow me to power wash about 1/4 of my small deck at a time, but the 4.0 allowed me to power wash the entire deck, plus the steps. It makes a big difference to have more long-lasting power, especially when wanting to get a power wash task done before it rains.

  19. Jazzyess70

    I was a first-time customer when in March 2021, I purchased a 14″ Cordless Mower that came with 2 20V Li-ion (4.0AH) Batteries. I have used the mower for 6 months, cutting my lawn once or twice a month and now one of the batteries (W3578) is dead! I am an unhappy customer since I had put my trust in the Worx name and their products.

  20. SteveLA

    The battery life seems to be very good under all sorts of uses. No matter what load I place it under it works extremely well and lasts it time under a full charge. I always feel confident taking extra batteries with me when I go to help out family member with yard work and clean up.

    Very pleased with this product,

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