Sun Joe Cordless Chainsaw Featured Image Reviews

Sun Joe 40-Volt 16-Inch Battery-Powered Chainsaw (iON 16CS): Product Review

Ease of use:
Cutting performance:
Final Thoughts

A saw that has a lot of potential once the stopping problems are resolved.

Overall Score 2.6

Available on Amazon

Buy It

How much wood would the Sun Joe cut if the Sun Joe had kept cutting? That’s the question we’re pondering after seeing what this saw could (and couldn’t) do. The Sun Joe 16 inch cordless chainsaw is a powerful tool, well balanced, with important safety features. However, its one flaw is that it kept stopping part-way through a cut.


Everything arrived in great condition and without a scratch. In the box was:

  • Cordless chainsaw
  • 40 V EcoSharp® battery
  • EcoSharp® battery charger
  • 16 in. (405 mm) Oregon chain (pre-mounted)
  • 16 in. (405 mm) Oregon guide bar (pre-mounted)
  • Cutting bar sheath
  • Manual with registration card
SunJoe Chainsaw packaging 1 small

Unboxing the Sun Joe Cordless Chainsaw.


Assembled Width 9.8 in
Assembled Height 30.3 in
Battery Voltage: 40 V (Volts)
Battery Capacity: 4.0 Ah (Amp hour)
Chain Size 16 in
Maximum Cut Diameter 14.6 in
Charging time 2.5-3 hours (full charge)
Power Source Cordless
Blade Length 16 in
Oil Tank Capacity 2.4 fl oz
Weight (chainsaw alone) 9.5 lbs
Weight (with battery installed) 12.8 lbs

Video Review

Now that you know the basic details of the Sun Joe iON 16CS chainsaw, you may be interested to see it in detail. Watch the video and then keep reading for full details.


Operating the cordless chainsaw is as easy as inserting the 4.0V 4.0Ah Lithium Ion battery into the battery compartment at the rear of the unit. Make sure to push it in tightly until you hear a click.

But before doing this, the battery must be charged to full capacity. It comes from the factory with a partial charge and takes about 2.0 to 2.5 hours to top off the battery before use. Don’t forget to do this! (Note: full charge from a dead battery is closer to 2.5-3 hours).

Sun Joe battery charger & battery small

The Sun Joe cordless chainsaw uses a Lithium-Ion Battery that needs to be charged before use

For complete details about Li-Ion batteries used in cordless chainsaws, see our Li-Ion Battery FAQ’s.

The battery also has a fuel gauge to let you know how much power is left.  With the push of a button you can easily read the three LED lights – one for empty, one for ½ charge, and the third for full charge.

Sunjoe Chainsaw Battery Life Indicator 1 small

The Li-Ion battery shows the amount of charge remaining

Sun Joe battery insertion small

Push the battery into the slot until you hear a “click”

Sun Joe insert battery small

The battery has a built-in thermal overload, so the chainsaw is not damaged. Keep this in mind later in the review as we discuss some cutting issues we encountered.


There are several safety features built into the Sun Joe cordless chainsaw. There is a safety button that must be pushed in before pulling the trigger or the chainsaw will not operate. Additionally, a hand guard protects your hands and acts as a chain break – if you touch the hand guard, the chainsaw automatically stops. There’s also a protective sheath to place over the blade during storage.

Sun Joe safety small

The safety button must be depressed before the saw can be operated


The Sun Joe 40V cordless chainsaw has very even weight distribution. This light chainsaw can be balanced on one finger without tipping to the front or the back. It moves fluidly and is easy to handle.

Sun Joe balanced small

The Sun Joe cordless chainsaw is evenly weighted, ensuring a smooth cut


Tools aren’t needed to adjust this chainsaw; there is a self-tensioning ring with an additional locking ring on the side that adjusts the bar and chain.

You’ll need oil to keep the chainsaw moving, so be aware that there is a spot to lubricate the chain on the side (oil isn’t included in the package so buy some before using the saw). The bar and chain oil reservoir was a cinch to fill up right before we tested it.

Sun Joe oil small

Filling the chain oil reservoir on the Cordless Sun Joe Chainsaw


The chainsaw “bucking” teeth are a great feature. On the Sun Joe chainsaw they’re made out of metal, whereas other saws have plastic bucking teeth that don’t bite into the wood as well. The chainsaw chain itself has low kick back, making it safer to handle.

Sunjoe Chainsaw bucking teeth small

The bucking teeth are made of metal, not plastic like other brands

Sun Joe Cordless Chainsaw Low Kickback

The Sun Joe chainsaw features a low kickback chain


Like the best roommates, this chainsaw is both quiet (reducing noise pollution), and clean (it advertises zero carbon emissions). ETL approved and Energy Star certified, you might just want to hug the tree after you’re done cutting it down.

Sun Joe in use small

The Sun Joe Chainsaw creates clean cuts – but has some flaws


The Sun Joe cordless chainsaw has amazing cutting power. It cut through large logs – but with some issues. The biggest concern we have about this chainsaw is the amount of times it stopped during cutting. Part way through cutting a log, the chainsaw would completely stop. Each time this happened we re-engaged the safety and the trigger and the saw would start up again. But when you’re constantly doing this just to cut through one log, it quickly becomes annoying.

Unfortunately, we had this same issue with the first model we tested of the Sun Joe 40V cordless chainsaw. The one tested in this review is an exact replacement (we returned the first one because of the stopping problems), but it still has the same issues. This could be an issue with the battery (perhaps overheating? It was warm to the touch) or the motor may be working too hard and a thermal overload switch kicked-in to protect the motor and its electronic components? I’m not too sure what the issue is – be sure to watch the video review to see this happen – multiple times.


From the owner’s manual: “To obtain a replacement part or product, please visit or email us at [email protected] for instructions. Please be sure to register your unit beforehand to speed up this process. Certain products may require a serial number, typically found on the decal affixed to the housing or guard of your product. All products require a valid proof of purchase.”


The 2-year warranty on the Sun Joe 40V cordless chainsaw covers “personal, residential use” only.


Your best best is to purchase the Sun Joe 40V cordless chainsaw on Amazon.

It’s also available online directly from Snow Joe for $299.99.


In summary, the chainsaw cuts well – until it stops. Both saws we tested stopped, on average, about once every 15 seconds while cutting, making it difficult to get the job done. If you’ll be cutting only smaller diameter branches, this is a good saw. But if you’ll be doing anything more heavy-duty you’ll likely end up frustrated.

Now over to you – have you tried a battery-powered chainsaw? What did you think? Share your thoughts in the comments below!

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Disclaimer – GPReview would like to thank Sun Joe for giving us a free sample to review. There was no expectation that it would be a positive review and we received no compensation for writing it. All opinions expressed here are those of the author based on personal experience using the product.

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