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Makita

Makita BL1840B 18V LXT Lithium-Ion 4.0Ah Battery, Black

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Availability: In Stock.
Fulfilled by Onkata
Arrives Saturday, Oct 24
Order within 23 hours and 27 minutes
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Size: 4.0Ah


Style: 1-Pack


Features

  • Integrated L.E.D. battery charge level indicator allows user to monitor battery charge
  • Provides up to 35% more run time per charge compared to BL1830
  • Reaches full charge in 40 minutes or less
  • Compatible only with Star Protection tools, indicated by the Star Symbol and/or Yellow Battery Receiver under the tool
  • Battery delivers consistent power and run time in extreme temperatures, even in winter (-4F/-20C)

Description

The Makita 18V LXT Lithium-Ion battery charges faster and works longer than standard lithium-ion batteries, giving you and your cordless tools unmatched performance and productivity to take on the most demanding applications. The Makita 4.0 Ah battery combines more run time (35% more run time per charge than the Makita BL1830 battery) with a category-leading charge time of only 40 minutes, so it spends more time working and less time sitting on the charger. For added convenience, it also features an L.E.D. charge level indicator to monitor battery charge. The 18V LXT 4.0Ah battery (BL1840) is compatible only with Star Protection tools, indicated by the Star Symbol and/or Yellow Battery Receiver under the tool. Makita 18V Lithium-Ion batteries resist self- discharge so they're ready for use even after long periods of storage. The Makita Rapid Optimum Charger (sold separately) is a smart-charging system that communicates with the battery during the charging process to monitor current, voltage and temperature. This advanced charging technology helps optimize battery life and deliver a faster charge. In addition, the Charger has a built-in fan to cool the battery for faster and more efficient charging, even in hot weather conditions. For improved tool performance and extended battery life, Makita created STAR Protection Computer Controls. STAR Protection is communication technology that allows the tool and battery to exchange data in real time and monitor conditions during use to protect against overloading, over-discharging and overheating. Makita, the innovation leader in cordless tool technology, has the world's cordless tool line-up powered by an 18V lithium-ion slide-style battery.

Number of Batteries: 1 Lithium Ion batteries required. (included)


Brand: Makita


Battery Cell Composition: Lithium Ion


Battery Capacity: 4 amp_hours


Recommended Uses For Product: Power Tool


Number of Batteries: 1 Lithium Ion batteries required. (included)


Brand: Makita


Model Number: BL1840B


Model Name: Makita BL1840B 18V LXT® Lithium-Ion 4.0Ah Battery


Global Trade Identification Number: 49, 98


UPC: 088381463898 088381426749 088321463896


Manufacturer: Makita


Included Components: battery


Item Type Name: 18V LXT, Lithium Ion, 4.0Ah, Battery


Warranty Description: Warranty


Battery Capacity: 4 amp_hours


Voltage: 18 volts


Reusability: Rechargeable


Amperage: 4 A


Compatible Phone Models: Makita XPH10, XFD,14,06,12 XDT13,14,15,16,19


Unit Count: 1 Count


Battery Weight: 1 g


Item Dimensions: 3 x 6.75 x 6.5 inches


Item Weight: 0.64 kg


Antenna Location: Power Tool


Battery Cell Type: Lithium Ion


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Saturday, Oct 24

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Similar Products

Top Amazon Reviews

    • Great
Size: 4.0Ah Style: 1-Pack
Nothing negative to say about Makita batteries. Been using the 18v LXT platform for over a decade. Bought these specific 4ah about a couple years ago and they work great
Reviewed in the United States on May 31, 2026 by Robert
    • Great Makita Battery!
Size: 4.0Ah Style: 1-Pack
This battery is not inexpensive compared to the ones made overseas. But you get what you pay for. This Makita lasts for at least 30 minutes on my weedeater in low RPM mode, which is what I use 90%of the time. I purchased an off brand for half of what the Makita costs and it was junk. Run time was maybe 10 minutes and it died after only 2 months. I will only stick with brand batteries if you want long lasting and powerful performance. ... show more
Reviewed in the United States on June 22, 2025 by PETER STAPLES
    • Superior Design, Construction, and Performance
Size: 4.0Ah Style: 1-Pack
Excellent quality, run time, and ruggedness. Attaches/detaches quickly and easily from tools and charger, and charges fast. The remaining charge indicator on the back, and the built-in electrical protection against failure are nice features. T For those who don't already know, note that they are no more "powerful" than the 3 or 2 amp batteries, they just last longer on a charge. Also, they are the same physical size and approximate weight as the 3 and 5 amp batteries. Only the 2 amp battery is notably thinner and lighter (but they last surprisingly long in many tools). If given the choice, I would simply buy the 2 amp batteries for smaller projects, and 5 amp batteries for higher demand projects. But you can't really go wrong with any of them. ... show more
Reviewed in the United States on October 7, 2017 by KJAG
    • Moma don't Take my Makita Drill Away - 4.0ah Makita Battery - just more of a good thing?
Size: 4.0Ah Style: 1-Pack
Purchased this for my XDT08 impact drill, which originally came with a 3.0ah 18v battery. The package states that the battery fits Makita tools that have the star on the battery compartment OR a yellow colored battery receiver. It fits my drills just fine. The value is good for me, considering that a two pack of 3.0ah hour batteries was about $120 at the big orange store a year ago. I haven't seen these on sale retail lately, so it seemed prudent to get another battery before they go away. The first of some 18v 1.5ah batteries in our collection just died after about 2.5 years of light service (the ones that came with the black and white 18v tools). So far, all of our 3.0ah batteries that came with the black and teal colored Makita 18v tools are holding up great. Having the 18v impact driver tool has revolutionized the way we to the initial builds and mockups. Our little impact driver has driven many thousands of fasteners - from short to long deck screws up to longer structural wood screws without issues. It was also useful in deconstruction work. The 3.0ah hour batteries often go several days of moderate use and easily a day or two of heavy use in an impact gun. Longer runtimes of a regular Makita drill, such as mixing paint, generally drain any of the batteries much faster - we don't use the battery tools for mixing paint after the first couple of times. We'd feel a great loss to be without the Makita impact driver and its partner hammer drill / drill. If it doesn't break down, you'll have to pry it out of my cold, dead hand. Battery that we received was in factory retail Makita package, undamaged, and it is taking a charge just fine. If there are no issues in a few months, I will add a star, or report back with what happened. If it holds a charge, lasts, and works as well as the 3.0ah that came with the tools originally, I'm super satisfied. So far, so good! Update August 2018 Still charging, still powering well. No issues. Adding star. ... show more
Reviewed in the United States on November 10, 2017 by Alien Bitflipper
    • I Neede To Replace My Makita 18V Battery
Size: 4.0Ah Style: 1-Pack
The Makita battery I received was well packaged and original equipment. I charged it up and it works perfectly. Great product.
Reviewed in the United States on June 26, 2025 by Vernon H. Messer
    • Good deal.
Size: 4.0Ah Style: 1-Pack
Received it earlier than expected, not bad. Battery came in a plastic baggie, which I didn't care for at all, which is why I only gave it four stars. Took 75 minutes to charge. Fits my tools, no problem there. Overall a great deal for the money. Bill
Reviewed in the United States on April 12, 2025 by william furman
    • Battery Fit or Miss?
Size: 4.0Ah Style: 1-Pack
This purchase was to confirm a theory...Does this battery fit my angle grinder? The grinder uses 3 Ahr battery but not the 5 Ahr battery. The 4 Ahr is the same as the five and will not fit in the 3 Ahr tools. I will use the 4Ahr in my other power tools. My next purchase is going to be the 6Ahr battery... ... show more
Reviewed in the United States on February 20, 2026 by PaulnLA
    • I think these are actually real Makita batteries.
Size: 4.0Ah Style: 1-Pack
Time will tell, but these passed all the normal tests for being authentic. I think they're real.
Reviewed in the United States on May 4, 2025 by Justin

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