Time for a Festool Drill.

[Terry Flowers]

Phil, I think that there are different NiCad qualities and technologies, some superior to others. The same mzy apply to NiMH. It is probably safe to assume that Festool uses the best of the breed. My own experience with NiCads is that they tend to lose charge unused much quicker than NiMH, although that experience is with 18v B&D NiCads, which is not a heavy line of tools. Those are a real pain, because the charge dissipates very quickly if unused if not on the charger. My DeWalt 14.4v NiMH batteries, on the other hand, hold the charge off the charger much longer, and the run time is much longer. The run time, however, is no doubt also a function of the battery quality as well as type.

I have read that it is not good to leave any battery idle without charging for long periods, as they do have a shelf life. If you have a tool with an advanced charger that maintains a safe charge level, it is probably better to alternate the batteries on the charger and in use than to keep one in reserve unused, or at least uncharged.

I am interested in other opinions, so battery experts please chime in.

Terry

[Chris Padilla]

The eccentirc chuck available with these drills is bordering on utopia for driving screws. Simply amazing and always saving my butt over the conventional centered drill bits.

Now if the eccentric chuck could fit on the right-angle chuck!! Whoa!!

I have the CDD-12 (old one, no longer available I think??) and the TDK-15 or whatever.

I don't quite get what this new chuck does but maybe I should just not get it...and not get it?! hahaha

[Rick Christopherson]

Because this discussion is duplicated on several discussion forums, I am pasting this answer from my other posting.

As I stated earlier (I think) the benefit to NiMH is that they weigh less for the same amount of power. However, that is the limit of their benefit, and that is why they are not as commonly found in high-draw power tools.

NiCd batteries provide a higher rate power output. This means that when you need to drive a really heavy load (like a big screw) the NiCd will power through it better than NiMH.

NiCd also has a lower rate of self-discharge (your original question). This means they will stay charged while on the shelf longer than a NiMH.

I've heard woodworkers question why tool manufacturers don't "step into the 21st Century" and start using NiMH batteries (or other types) more often. This is a short-sighted observation from people that don't understand how the chemical reaction within batteries occurs. These other batteries are GREAT in low-demand products like cameras, but they do not perform as well in the high-demand applications. Newer chemistry is allowing these batteries to become better, but they still won't equal the performance of the NiCd.

[Frank Pellow]

Because this discussion is duplicated on several discussion forums, I am pasting this answer from my other posting.

As I stated earlier (I think) the benefit to NiMH is that they weigh less for the same amount of power. However, that is the limit of their benefit, and that is why they are not as commonly found in high-draw power tools.

NiCd batteries provide a higher rate power output. This means that when you need to drive a really heavy load (like a big screw) the NiCd will power through it better than NiMH.

NiCd also has a lower rate of self-discharge (your original question). This means they will stay charged while on the shelf longer than a NiMH.

I've heard woodworkers question why tool manufacturers don't "step into the 21st Century" and start using NiMH batteries (or other types) more often. This is a short-sighted observation from people that don't understand how the chemical reaction within batteries occurs. These other batteries are GREAT in low-demand products like cameras, but they do not perform as well in the high-demand applications. Newer chemistry is allowing these batteries to become better, but they still won't equal the performance of the NiCd.

Thanks for that (very useful to me) information Rick.

[Dave Falkenstein]

Holy cow! How can you guys justify the cost of those things? Are they really that much better than a Bosch, Dewalt, Makita, etc.?

Hmmm - I don't think you justify the cost of Festool products. You just agree to pay the price in order to get superior tools.