The technology that is being used in cordless power tools has come on quickly over the last few years. Firstly NiMH batteries were intorduced to replace Ni-Cad batteries in cordless power tools, and now the new Lithium-ion (Li-ion) batteries are replacing NiMH batteries in the industry. Most of the big tool brands are now employing 18v Li-ion batteries in their cordless power tools. One such manufacturer being Craftsman, whose 18v power tools are leading the way in the use of this new technology.
Li-ion batteries have been used in other electronic devices for a while, for example laptop computer batteries, but is only recently that they have become popular in cordless power tools. It is a great advance in the DIY and buiding industries as Li-ion batteries have so many benefits over older battery types. The recently brought out 18v power tools will be advantageous to both professionals and hobbyists performing home DIY, alike.
One of the greatest benefits of a Lithium-Ion battery cordless power tool is the fast charging time. A Li-ion battery can completely re-charge in about 15-20 minutes using a rapid charger, whereas a Ni-Cad battery takes a couple of hours, often longer, and even NiMH batteries take a long time to charge.
This can be very annoying if you don't want to wait to charge a tool that you need to use, or could even cost you valuable time and money on a job. When using cordless power tools traditionally you have to remember to put them on charge at least a few hours before you need them, often the night before.
Another advantage of Li-ion batteries is that they hold their power over time rather than loosing it like Ni-Cad and NiMH batteries. You can charge a Li-ion battery and leave it for a couple of months and when you come to use it again it will still have some power. If you charged a NiMH battery and left it for several weeks it would probably have no charge left when you came to use it so you'd need to charge it before you could use it.
Li-ion batteries also often come in twos so you can work all day without ever having to wait for one to charge. They have another advantage over older batteries also, in that they are incredibly light considering the amount of power they offer. This makes them easy to use, even for less experienced people who are less used to holding up heavy tools for periods of time. Unless you are fairly strong or fit, holding a heavy tool up at eye level over a period of time can really make your arms ache.
It looks like the future of cordless power tools is going to be Lithium-ion battery 18v power tools, as they offer so many benefits over older battery powered tools. Many professionals are using 18v power tools already and it looks certain that hobbyists and home DIY-ers will follow suit to get all the benefits of this technology.