Professional Tool Reviews for Pros
Around here, we primarily focus on the tools and gear surrounding the construction industry. That makes the 21700 vs 18650 lithium-ion battery cell conversations incredibly relevant to us. After all, these lithium-ion power sources reach far beyond the latest cordless tools. They’re driving innovation in Teslas, hoverboards, the vaping community, and so much more.
21700, 18650, 20700 and others simply refer to the physical size of the lithium-ion cell. For 18650, it’s an 18 mm diameter x 65 mm length. 21700 is 21 mm x 70 mm. While the explanation is simple, the difference is profound. It’s easy to see with a quick volume calculation.
An extra 5 mm of length and 3 mm of diameter gives us 47% more volume. That’s a little more than 7,700 cubic mm of space to pack with energy-delivering anode, cathode, and electrolyte material.
The most obvious benefit of going with 21700 vs 18650 is that the extra density means there’s more available energy in them to run your tools and gear longer. Batteries that we see using 18650 cells for power tools range from 1.5Ah (1500mAh) to 3.0Ah (3000mAh) in each cell. 18650 cells on the higher end of that scale have reported issues and 2.5Ah (2500 mAh) cells seem to be where most manufacturers settle at the top.
On the other hand, 21700 cells start around 3.0Ah (3000mAh) and go up to 4.0Ah (4000mAh) for power tool batteries. It’s why we see compact (1P) packs that have 3Ah or 4Ah designations all the way up to 12Ah (3P) big boys.
From the perspective of comparing 21700 vs 18650 in power tools, you’re looking at a 50%–100% runtime gain over today’s standard 18650 packs. Outside the power tool industry, some of these cells reach 5.0 Ah (5000mAh).
Batteries like the Bosch Core18V, Milwaukee M18 High Output, and Metabo LiHD packs do more than just take advantage of longer runtime. They improve their packs’ cooling abilities and build them with better materials that reduce resistance (ohms). The result is a battery with much greater power available.
Take Bosch, for example. Their standard 18V batteries can produce up to 800 watts of power output. When they upgraded to Core18V, it went up to 1440 watts—an 80% power increase! Other brands report significant power gains as well.
It gives them the ability to produce cordless tools that we didn’t think we’d ever see without a cord just a few years ago. And many of them are outperforming their corded counterparts now.
Power tools are hardly the end product. Outdoor power equipment for lawn care and landscaping, battery-powered inverters, and battery-powered construction equipment are all starting to have cordless options thanks to 21700 lithium-ion battery cells.
On the clock, Kenny dives deep to discover the practical limits and comparative differences for all kinds of tools. Off the clock, his faith and love for his family are his top priorities, and you'll typically find him in the kitchen, on his bike (he's an Ironman), or taking folks out for a day of fishing on Tampa Bay.
If you’re a contractor who appreciates great workmanship, getting away from the 9:00 to 5:00 (or 7:00 to 7:00) opens up the opportunity to experience some of the best architecture America has to offer. The nice thing is, excellent architecture tends to be close to great food and entertainment, making it easy to take along your […]
After reviewing power tools and hand tools for well over a decade, we get asked the Lowes vs Home Depot question a lot. To determine whether Lowes or Home Depot is a better store we need to cover a lot of ground. Looking at the two home improvement warehouses I don’t think you can truly […]
What is an impact driver and what do you use it for? It’s a question we all had to learn the answer to at some point and we’re glad to help you out! Whether you’re adding to your personal tool collection or you’re new to the construction industry, they are incredibly useful tools and are […]
Milwaukee Tool announced the opening of a new Engineering Design and Innovation Space or “Technology Office” in Chicago, Illinois. Which begged the question: What is this multi-billion dollar tool company planning for this downtown location? The Big Deal Behind Milwaukee’s Chicago Office Milwaukee Tool invested over $14 million dollars in this new facility. They renovated […]
Another suggest for a video: It would be great to see which tool lines, both 12v & 18 (20)v are using which battery cells. Maybe just a quick rundown or listed on your site. Thanks as always!
Here’s my question: A 18v 4.0ah with 21700 cells is going to be larger and weigh more than one with 18650 cells – Am I right? If I am, then it is a trade-off between physical size and power/run time -Yes? We are seeing with Milwaukee M12 Fuel and even now Skil PowerCore 12 incredible power and run-time in a much smaller package with those 21700 cells – Nearly or even better then 18v packs with the standard 18650 cells. So to me that is a sweet spot. There is a reason I bring this up. We have Pedego Electric… Read more »
Avec des si on refait le monde, déjà y a une belle évolution de charge rapide sans trop de chauffe, après d’ici la vaut peut être mieux couplé avec des supercondencateur pour un stockage encore plus rapide et une decharge lente
If I were a flashlight manufacturer, I would offer flashlights that use 26650 cells instead of 21700 cells. This would let customers use either a higher capacity 26650 cell or a 18650 cells (that they often already own) with a sleeve type adapter.
Than again, this makes too much sense because it uses existing parts instead of proprietary parts that are not backward compatible.
When is Makita going to get on the 21700 bus?
As an Amazon Associate, we may earn income when you click on an Amazon link. Thanks for helping us do what we love.
See our Privacy Policy and Terms & Conditions.
Pro Tool Reviews is a successful online publication that has been providing tool reviews and industry news since 2008. In today’s world of Internet news and online content, we found that more and more professionals researched a large majority of their major power tool purchases online. That piqued our interest.
There’s one key thing to note about Pro Tool Reviews: We’re all about the professional tool user and tradesman!
Copyright ©2008-2022 Pro Tool Reviews, LLC. All rights reserved.
Professional Tool Reviews for Pros