Ryobi Battery RB18L40 18V One+
(8 reviews)
Compatible with every tool in the Ryobi One+ range, this genuine RB18L40 battery offers a 4Ah capacity at 18V for constant, reliable power.
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Characteristics
- Capacity: 4 Ah / 72Wh
- Voltage: 18V (Lithium+)
- Compatibility: Ryobi One+ tool range
- Constant power, fast charging, genuine Ryobi
Detailed overview: Ryobi Battery RB18L40 18V One+ - photo 2
The RB18L40 is a genuine Ryobi battery, compatible with the entire One+ range of cordless tools: drills, drivers, saws, grinders, sanders and many more. Thanks to Lithium+ technology, it delivers constant power throughout the discharge, fast charging and an excellent lifespan. With a 4Ah capacity (72Wh) at 18V, it suits both occasional DIY and more intensive use. An on-board 4-LED fuel gauge lets you check the remaining charge at a glance, so you are never caught out in the middle of a job.
This battery is not just for tools: paired with the Ryobi 18V One+ 150W inverter, it becomes a self-contained 230 V socket holding 72 watt-hours, enough to run a laptop or a lamp far from any mains supply.
Our tester's review: Yoni Marchal-Laporte
The RB18L40 keeps its most important promise: it powers over 200 tools across the One+ lineup without fuss, including older models, an argument few rival ecosystems can match. Its 4-LED indicator reads at a glance, and its 24-month warranty, extendable to 36 by registering the product, is reassuring. No independent measurement of its capacity or actual delivered energy was found, though, leaving buyers to rely on the manufacturer's own figures, and the price seen, around $65, runs noticeably higher than some comparison sites suggest. A newer generation, the RB1840X, is now found cheaper through the same channels. A pack left flat for months can also refuse to restart, a known lithium-ion limitation rather than a flaw specific to this battery. For anyone who already owns One+ tools, it remains a sound choice; for a first purchase, the generation question is worth asking first.
In-depth review Ryobi RB18L40 18V One+: our full review 4.0/5 Read our full review → Actual delivered capacity 3.7 Compatibility and ecosystem breadth 4.4 Reliability and long-term endurance 3.9 Charge time and tool runtime 3.9 Build and interface 4.0 Compatibility and camera recognition not measured Reliability and cycle count not measured Cell build and safety not measuredFrequently asked questions: Ryobi Battery RB18L40 18V One+ - photo 2
Yes, and that is the range's central selling point: Ryobi has not changed the One+ 18V mount since its launch, so a recent pack also powers a much older tool. Just check that your tool carries the One+ logo and not another of the brand's platforms.
Not necessarily. A pack left flat for several months drops below the threshold the protection electronics will accept, and the charger then refuses to start. That is sometimes recoverable with a brand charger, often not. To avoid it, store your packs at around half charge and top them up every six months: that is what makes the biggest difference to their lifespan.
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Published on 02/09/2026