Caring for Your Battery-Powered Chain Saw

As one might expect, the maintenance and care of battery-powered chain saws is easier and less expensive than that of their gasoline-powered counterparts. Other than bar and chain maintenance, which is essentially the same with a gas-powered saw, maintenance for battery-powered saws pretty much boils down to keeping the battery charged and properly cared for.

“Battery saws are much easier to operate and maintain,” says Mike Poluka, product manager with Stihl, Inc. “On the gas side, you have to mix fuel and oil, making sure the fuel is fresh and mixed with quality oil. Sometimes a member of the crew can forget to mix the fuel and oil or do it properly. On the battery side, it’s plug-and-play.”

Continuing, Poluka says, “With a battery saw, you do not have the effort and expense of replacing filters or plugs or cleaning the carburetor or performing any other standard maintenance that comes with traditional gas saws.

“There are, however, regular maintenance steps and intervals, and all recommended battery-saw maintenance is outlined in the instruction manual,” he explains. “With a battery saw, it is mostly visual inspection and cleaning. If a machine gets dirty with sawdust, it’s mostly about cleaning the cooling fins and keeping a sharp chain,” he says, adding, “If the chain is dull, performance falls off , which is true for either a battery or gas saw.

“Each Stihl model has a specified bar and chain, although some can be interchangeable between models, and the bar can be rotated 180 degrees to extend its life,” just as with a gas saw, Poluka notes. He stresses that, “Because there are so many different-quality chains and bars, we recommend only Stihl brands, which Stihl designs and produces.

“When it comes to chain adjustment, it’s intuitive and easy to do. On most (but not all) of the battery models, there is a toolless chain tensioner, but on the higher-end models the chain adjustment is similar to a gas machine,” he says.

Regarding inspection for bar wear, “That depends on use, not whether the saw is gas or battery. What to watch out for as you’re working is if the saw veers to the left or right on a crosscut. That’s an indication the bar is possibly worn.”

One of the most important things, Poluka says, is to, “Clean the saw at the end of the day. To clean off the machine, wipe it off , then clean the cooling fins.”

When asked if there is any danger in spilling bar oil onto or into the battery receptacle during maintenance, Poluka says that’s very unlikely. “The way the battery is positioned, you would have to intentionally pour oil onto the battery.”

Anytime one is working on a battery saw, Poluka says the first step should be to remove the battery to avoid inadvertent startup. “It’s a good practice to take the battery out of the machine when not in use to help prevent unintended consequences. For example, someone not familiar with the equipment could accidentally hit the throttle trigger.

“When you’re done using the saw at the end of the day, put the battery in a cool area and do not store the battery and saw outside,” he recommends, adding, “Most batteries are OK if they are exposed to rain when in use, but not when stored long term.”

Typically, during regular use, when the battery runs out of life, it’s also time for bar oil, he says. “When the battery goes dead, fill the chain-bar oil reservoir and get a freshly charged battery.”

He warns that batteries for Stihl’s pro series of saws are not interchangeable with consumer-saw products, and, for the pro series especially, there are specific batteries for specific saws. “That’s not to complicate the product line but to offer the best power options within the product range. It’s critical to use the approved battery for your chain saw, which is specified for power-to-weight ratio and ultimate performance.

“Stihl batteries should be stored out of the saw and with a 40% to 60% charge level to prevent a deep discharge, which can render a battery useless,” Poluka explains. “There are LED lights on the battery that tell you how much battery life you have.”

He says chargers are designed to charge up to 80% at a standard current rate, then at a trickle for the last 20%, which he says helps maintain battery life. “As soon as the battery is charged, the charging system shuts down. Also, the chargers communicate intelligently with the battery to monitor the charge level, and, if the battery gets too warm while charging, the system will wait until the battery is cool.”

Regarding use of the battery in extreme temperatures, Poluka says, “Our battery saws are officially approved to 122 degrees Fahrenheit. And we recommend operating at not lower than 14 degrees Fahrenheit.”

Poluka recommends using regular power receptacles (outlets, not inverters) for charging for a standard, consistent and reliable voltage.

At Husqvarna, Ben McDermott, product manager for professional chain saws and accessories, calls battery-saw maintenance “a significant time saver.”

There are recommended plans for professional products – daily, weekly and monthly. Before each use, he advises, clean all external parts, ensure the power trigger and lockout mechanism function correctly, clean the chain brake and make sure it is operating properly, sharpen the chain if needed, check the drive sprocket and check the bar to see that it is clear of burrs. Clean the air inlet and check all hardware and connections, the guide-bar notch and battery connections. Check to see that the saw is operational.

“Weekly, make sure the guide bar is well maintained and free of burrs,” McDermott says. “Replace as needed. Monthly, clean the battery connections, fill the oil tank and blow through the battery and cooling slots with compressed air.

“Because there are significantly fewer moving parts – for example, with the Husqvarna-designed brushless motor – there is little maintenance. The chain is easy to adjust, similar to a gas saw, and some have a toolless adjusting feature.”

McDermott stresses the importance of a sharp saw, since “Husqvarna uses lighter, smaller chains, comparable to those on smaller-cc gas saws. Chain speed and acceleration tend to be higher for Husqvarna battery saws versus our gas models,” he explains.

“Regarding special attention, I would say the main issue is around charging, especially among professional users, to ensure they have enough battery power to get through daily tasks,” McDermott says. “In Husqvarna’s popular pro series, batteries are compatible with one another, and the higher-up series feature higher amp hours for longer run times.”

One of the features Husqvarna provides for optimal battery performance is a design to keep the power pack cool while in use. He adds, “We’ve also designed an internal battery-management system that maximizes up-time and protects from over current, under voltage and high temperatures.

“The user needs to clean and inspect battery terminals, and we do not recommend user disassembly; take the battery to a qualified service dealer,” McDermott recommends. “Batteries have a shelf life of 24 months new, and lifetime depends on application and care, yielding up to 1,500 charge/discharge cycles.

“Basic battery and charger maintenance is to keep them clean and dry. Do not keep a fully charged battery in the charger. Remove it from the saw when not in use, and store between 41 and 77 degrees Fahrenheit. Ambient charging temperature is 41 to 114 degrees, and ambient work-temperature range is 12 to 104 degrees. Storage in extreme heat can damage cells over the battery’s lifetime and reduce the number of recharge cycles. We do not recommend trickle charging.”

He stresses how important it is to, “Clean the battery and contacts. Debris can damage not only the battery but also the product.

“We do offer an inverter that allows for the battery to charge from a vehicle’s 12-volt DC system – any lead-acid battery – converting to 220-volt AV for your Husqvarna chargers,” McDermott says, adding, “We are investigating a solution for multiple-battery chargers for use in the field by professionals.

“We do not recommend restoring worn-out batteries; the chemistry does not lend itself to reconditioning,” McDermott says. “Since these are lithium batteries, they can be recycled only at permitted facilities, and we recommend checking local regulations.”

“The operating costs of a battery-powered saw compared to a gas-powered saw are lower in terms of not having to purchase fuel and mix oil to run it,” says Brad Mace, chain-saw product manager for Echo, Inc. Of course, he adds, “You also do not need to replace common-wear items like spark plugs, fuel lines, fuel filters or air filters. One factor to keep in mind with a battery-powered saw is that a second battery should be purchased to avoid downtime and/or recharge time when a battery loses its charge.

“Professional-grade, battery-operated chain saws have a side-access chain tensioner, which makes adjustment quick and easy – and done in the exact same manner as a gas-powered saw,” says Mace. “Over time, sawdust and chips will accumulate within the sprocket cover with either variety, and that portion of the saw should be inspected and cleaned on a regular basis to maintain peak efficiency,” he says, adding, “Slow cutting, small chips or fine dust and a feeling of forcing the saw through the wood are all signs that maintenance should be done on the saw, regardless of power source.

“Some battery-operated saws feature built-in batteries and some have removable batteries. Echo’s 58V model features a removable battery, and it’s very important that only the model battery that is shipped with the unit be used to operate the saw. By and large, batteries are not interchangeable with other brands,” Mace stresses.

“Batteries and their accompanying chargers should be stored and operated at temperatures recommended in the manufacturer’s operator’s manual. Extremes of heat and cold should be avoided to prolong battery use and peak efficiency. For long-term and even short-term storage, batteries should be kept at full charge,” he says, adding, “Clean the battery’s case with cloth. Avoid touching the battery’s contacts.”

One of the beauties of a battery-powered saw is that “they are largely maintenance free,” states Mike DeMaira, product manager for Ego, a manufacturer of cordless outdoor equipment and new TCIA Corporate Member based in Naperville, Ohio.

Unlike some other saws, “All Ego chain-saw batteries are interchangeable. Saws come with a 5-amp battery, but can be upgraded to 7.5 amps. We also have a 2.5-amp battery; it is not recommended for pro work,” DeMaira says, adding that a 10-amp battery is in development.

Maintenance, he says, is largely a matter of checking the operating features and cleaning the saw before and after use. “Simply wipe or brush the saw down.” He warns not to use sharp brushes or cleansers and to check the company’s online cleaning video.

“The method of removing and adjusting the chain is much easier than with a gas saw, which usually involves a dual bolt and a wrench. With our system for the 18-inch saw, the auto tensioning is easy – turn the tensioner a quarter-turn backward and forward, and the auto tensioner kicks in. For the 14- and 16-inch battery saws, it is toolless. Simply turn a dial to loosen or tighten.”

DeMaira says Ego opts for a low-profile chain for improved cutting efficiencies and, consequently, more run time.

Ego offers two chargers, one a standard charge time and one faster. Both, he notes, will charge to full capacity, shutting off automatically to prevent overcharging. Recommended charge temps are 41 to 104 degrees, with optimal storage at 50 to 80 degrees. “In winter, I do not keep my batteries in the garage, not because it is not safe, but so they are definitely ready to go. The equipment will start with old batteries, but not as efficiently. Same goes for overheating.”

Speaking of overheating, “All our electronics are smart. If the saw starts running at too high a temperature, it will not start or will shut off to prevent overheating,” DeMaira says, noting Ego employs a patented technology that draws heat away from overheated battery cells.

Chad Bishop, product manager for Greenworks Commercial, another manufacturer of battery-operated power equipment and a new TCIA Corporate Member based in Mooresville, North Carolina, echoes the refrain that, “Battery-powered saws are low maintenance compared to gas. There is no carburetor, no gas, no air filter and no pull cord. A battery charge costs anywhere from four cents to eight cents, which is far less than a tank of gas.”

Regarding the chain, “We use the same system as professional gas saws, and utilize the same sharpening and care techniques used on a gas saw,” says Bishop, adding that chains used on Greenworks saws are commonly found on gas saws.

He states that, “Not all cordless saws run at gas-chain speeds. Our GS181 runs at 20 meters per second, which is equivalent to a gas under no-load. However, when under a cutting load, where a gas saw will slow down, our GS181 will maintain a high chain speed, resulting in faster cut time.

“Lithium-ion batteries are affected by extreme temperatures,” Bishop says. “For best performance, we recommend discharging between 20 and 110 degrees Fahrenheit.”

Testifying to the stoutness of battery-powered saws, Bishop contends, “Battery saws are just as rugged as gas saws. We do recommend storage in a dry environment.

“All of our batteries are removable, so we add flexibility for our end users to utilize the battery across multiple tools. It provides the end user the ability to switch out the battery and replace it with another battery for extended run time,” he says, warning, “You should only use Greenworks-branded batteries for Greenworks products. Do not use non-branded batteries with any commercial battery equipment.

“Once an end user purchases a product from us, they should read through the manual and follow the steps recommended in that document. The battery should be charged fully by the end user before the first use. Unlike NiCad batteries, our lithium-ion batteries do not have a memory effect. You can charge and discharge at your leisure,” Bishop reports.

However, he adds, “An extended period of storage (years) can cause the battery to drop below an acceptable voltage. Safeguards on the charger will not charge the battery below a certain voltage.

“Batteries should be clear of loose debris. Do not apply water or cleaning solutions to a battery,” he states.

Single, rapid battery chargers currently are available, dual-port rapid chargers are on the way and power inverters for trucks are commercially available through third parties, according to Bishop.

Like electric cars, battery-powered chain saws look like they are here to stay. Caring for your battery-powered saw is very simple and the steps are limited. That said, just as with a gas-powered saw, proper care and maintenance will increase performance and extend the life of your battery-powered chain saw.