Cordless electric string trimmers are a terrifically green and convenient alternative to gas-powered string trimmers.
Because they're battery-powered and cordless, there's no gas or oil to mess with, and your range of motion isn't restricted by an extension cord.
New battery technology has made these weed whackers more popular than ever, often featuring enough battery life to finish the same jobs that a gas trimmer can.
Rechargeable batteries for lawn tools have improved so much that they now last as long as a tank of gas. If you'll be doing large projects, consider a backup battery so you won't have to wait for the battery to recharge should you run out before you're done.
And remember that the battery only drains when you're squeezing the trigger. Only run the trimmer when you're trimming, and the battery lasts even longer.
Ni-Cad battery-powered string trimmers are generally the least expensive cordless models. Ni-Cad batteries are relatively heavy, and you will see a noticeable drop-off in power and performance as the battery runs down to the end of its charge.
Ni-Cad batteries are on their way out. Many manufacturers are beginning to exclusively use lithium-ion batteries for better performance and longer battery life.
Lithium-ion batteries are the most recent innovation to power string trimmers. Lithium-ion batteries are available in several different voltages: 18-volts, 20-volts, 24-volts, 40-volts, 56-volts, 80-volts, or 82-volts.
Lithium-Ion batteries are extremely popular for 3 main reasons:
1. They are lightweight – up to 50% lighter than a comparable Ni-Cad battery – so the string trimmer won’t weigh as much when in use.
2. They do not experience any drop-off in power or performance as the battery runs down. Power output stays consistent through the entire cycle of use.
3. They can be recharged up to 3 times as many times as a Ni-Cad battery before the battery needs to be replaced.
Curved Shaft string trimmers are good for grass and weed trimming in open areas. Because of the curved shaft design, you will not have as much maneuverability trimming in tight spaces, such as under a fence.
They are considered easier to use than straight-shaft trimmers, but appear to be disappearing from the cordless category.
Straight Shaft string trimmers are more functional in tight spaces. You can trim in hard-to-reach corners or areas farther away from yourself.
Many models feature a telescoping shaft, meaning you can make the shaft as short or long as you need to comfortably trim.
Some cordless string trimmer models are a 2-In-1 style, meaning you can use them for multiple purposes.
Use it as a string trimmer, or turn the pivoting cutting head to use as a grass edger.
The video above describes how to use a 2-In-1 string trimmer.