Where conventional power tools are too big and bulky, the compact Hitachi cordless tools can easily develop their full power, all thanks to powerful Hitachi batteries. Cordless tools have come a long way, especially with the introduction Li-Ion technology. Most cordless tools like hammer drills and circular saws are light enough that they can be handled by both men and women. 18v power tools are popular because they provide the freedom to work anywhere. Hitachi's 18v power tools are leading the way in the use of the new Li-Ion batteries.

Nickel cadmium (NiCad), lithium-ion (Li-Ion) and nickel metal hydride (NiMH) are the three types of batteries you will find inside Hitachi cordless tools. So, what is the main difference between Ni-MH and NiCad cells? Simply, NiMH batteries have more power. But the chemistry behind NiMH is similar to NiCad. But NiMH batteries are far less tolerant of overcharging and have more sensitive charging and discharging parameters. On the other hand they do not contain expensive (and environmentally risky) cadmium.

Difference between NiCad and Li-Ion batteries is a big subject, with numerous different opinions. However, generally speaking you will find that NiCad batteries will give you roughly 800 recharges. Lithium ion batteries will give you 2,000 or more recharges. You can recharge lithium ion batteries as often as you want. If nickel cadmium batteries are recharged frequently they develop memory effect and discharge more quickly. Memory effect is an effect in NiCad batteries that causes them to hold less charge over time. With lithium ion batteries that doesn't happen.

The other noticeable difference is the weight. Lithium ion batteries weigh less, volt for volt, than their nickel cadmium counterparts. Lithium ion batteries are small, lightweight, and powerful with reduced size and weight. In a head to head comparison of performance the lithium ion tool can easily compete even with conventional cordless tools. It's just as powerful and quick but it's a lot lighter. Lithium ion technology reduces the size of the battery by half.

The final takeaway is that lithium ion battery has virtually no self-discharge. They are always ready to use. This allows a Li-Ion battery to be stored for months without losing charge. In general, a normal nickel cadmium battery will discharge itself at about 3% per day. The Li-Ion battery will maintain that charge. Also, they have no memory effect and deliver full power every time they are recharged. NiCad batteries suffer self-discharge rates as high as 25% per month. Fully charged lithium ion tools can maintain their charge until they are used again; sometimes for days, week or even months. Conventional NiCad and NiMH batteries can completely discharge by the time you need them again. With Hitachi lithium ion batteries there is no self-discharge to slow you down.

Hitachi Li-Ion batteries are compatible with Hitachi Ni-Cad Batteries of same voltage. Both NiCad and Li-Ion batteries will fit into almost any Hitachi power tool. The only thing that needs upgrading is the charger.

When pushed to the limits conventional cordless power tool heats up fast. Every overload could be its last. The intelligent electronic battery protection protects the Hitachi lithium ion battery from overheating, helping to ensure long serving life.

Small size and high power are also available for cutting with the versatile Bare Tool Hitachi C18DLP4 18-Volt Lithium Ion 6-1/2-Inch Circular Saw and for lighting with the handy Hitachi UB12D Torch 9.6-Volt to 12-Volt Pivoting Head Flashlight.