I was just about to purchase my new set of DeWalt power tools from Costco (great price...forever guarantee) but I just went to homedepot.com and they just introduced the first Lithium-Ion battery powered cordless tools! What does everyone think?

Check it out here:
http://www.homedepot.com

Link is on the front page.

[This message has been edited by ckeck (edited 10-15-2005).]

How many iterations of the cordless tool has Milwaukee had now? Four? Do you think they finally got it right?
Likewise, Makita got complacent, and lost a market it once "owned".

Phooey on "new and improved" products...my "old" ones will continue to work fine!

Now if everybody had interchangeable batteries....that would be something to crow about!

If anything, I find myself 'regressing' back to corded tools more often these days. Thank heaven BigToolCo can't give you a weird plug that only fits their receptacles!

John,
That's quite true, first cordless drill I ever owned was a Makita, I wouldn't buy another now.
Also,
Indeed it would be, but I can't really see that happening anytime soon.
One point I'd like to make about batteries for these drills, I wish that the cost of replacing a worn out battery pack wasn't as high as what it is.
I've stored my old drills away because the cost of getting the batteries replaced or repacked was more than the price of a new tool.
Meanwhile you are left with a tool you can't use or sell just because the battery pack gave up the ghost. GRRR
I only use cordless tools when working outdoors anyway, or there is no power supply nearby.

I found out the hard way that with very little work Dewalt and Milwaukee batteries could be fixed. On the batteries I've fixed, just take out the screws and look for either a shorted connection or a loose connection. Break out the solder gun and a couple of minutes later you done. The batteries come with a self-sticking metal strip to tie the batteries in series, I do not know were to get the replacements for these. If anyone knows please post. Thanks Sparks30

And if your batteries are just not holding a charge like they used to, you can get almost any battery pack rebuilt at Batteries Plus .

Sparks30,

There are certainly any number of companies that will rebuild battery packs below what the manufacturer charges for a new pack.

If you want to do the work yourself, the individual cells can be bought at plenty of places. They are not inexpensive. Figure $4.50 and up PER battery depending on what kind of batteries you have now. Sanyo and Panasonic are the big names in the rechargeable battery business. Just a quick look turned up a site that sells individual cells:
http://www2.towerhobbies.com/cgi-bin/wti0097p?MANUFACTURER=SAN&FVSEARCH=CELL+++

Hope this helps.

My gut reaction is that you're going to pay a lot for a fancy battery may not pay for itself with increased productivity. For some guys the lighter weight and increased battery life will be worth the additional cost.

My limited understanding of the technology is that it’s not quite as simple as taking out the NiCd or NiMH battery cells and replacing them with lithium ion cells. Lithium ion batteries have a different “power curve” than NiCd or NiMH so there’s additional layer of electronics in the battery that essentially shuts off the battery (and obviously the tool) at a certain level of discharge. Which could really suck if you’re 20ft. up on a ladder and two turns short of fully driving a screw. Milwaukee deals with this by adding a “fuel gauge” to the battery pack.

While their low weight and small size make them ideal for cellphones and laptops, lithium-ion haven't been suited for cordless drills and other things that draw a lot of current. It used to be that li-ion was very delicate, easilyt destroyed by short-circuit or overcharge and hampered by a very high internal resistance. These shortcomings have now been overcome with new robust high drain cells, but only at the price of a much lower energy density. This diminishes the advantage over NiCD or NiMH.

Mike, I just got off the phone with my local Batteries Plus store. They charge $4 per cell (voltage/1.2), parts and labor. To me, that's a bargain.

Larry, $4 * 18V/1.2 = $60?

I have to admit I was a little skeptical of the V28 battery system when I first saw it but I figured with a 2 year battery warranty and the five year tool warranty it was worth a shot. While I have only had the bandsaw a couple of months it has surpassed my expectations. Everyone who sees it or tries it falls in love with it. For EMT and unistrut you cant beat it. For aluminum it doesnt do me much good because I have to setup a threading station anyway. I usually recharge the battery during lunch, and with that I can keep going all day long. I will admit I am addicted to power tools (especially cordless) but I think that this milwaukee line is going to do pretty well as more people start to use them and see what they can do.

Lithium-Ion battery packs cannot be rebuilt.

The individual cells are not available to rebuilders..even if they were, the battery pack itself, at least on laptop computers, has "smart" circuitry on it that will disable the battery after a certain number of charge/discharge cycles.

The batteries could probably be purchased for less. Sometimes the hobby shops can have a bit more markup. Shop around some of the electronics suppliers such as Digikey, Mouser, Newark, etc. They usually also have qty discounts when you are buying 10 to 15 or more. May be worth a look.

Lithium Ion cells are available, and custom packs are getting less expensive. I've been using them in my 'homebrew' bicycle headlight for about 9 months now.

Check out batteryspace.com for Li-Ion cells, packs, chargers, and protection circuits.

IMHO I would be very leery of Li-Ion cells in power tool applications, but am willing to believe that they could work in a well designed system. NiCd and NiMH cells are really far easier to use and more robust, but Li-Ion is a better chemistry (lighter, greater energy density, better for the environment, etc.), and if the protection circuitry is carefully designed, and the battery is large enough to supply the load, then they should be quite good.

Battery power tools are often 'specification gamed' with battery voltage. But battery voltage does not tell the whole story; you also need to consider the total _energy_ stored in the battery (watt hours) and the _power_ available at any given time.

In general, of NiCd, NiMH, and LiIon, NiCd is the heaviest and has the least energy storage per unit mass, but has the best power output per unit mass. NiMH has better energy density, but worse power density, and LiIon has the best energy density and the worst power density.

Power tools are generally used in a very bursty fashion, high power for short periods with delays between use. This means that a LiIon power tool will need to be carefully designed to have enough _power_ available for the bursts, but if this is taken care of, all of the other factors (weight, capacity, etc) will be _great_.

-Jon

For what it's worth, I have the drill from the new Milwaukee 28V line. So far, it has been really good. It's not as powerfull as a corded drill (duh), but for sure it has more ass than any cordless that I have owned/used before. I think the real test is coming soon...

How does it work in the winter? How long does the charge last vs. all the 18V, 14.4V, etc. tools available? How do the different battery types line up when subjected to low temperatures? I've read about voltage/discharge ratings for different battery tools, but I don't know of any climate related tests. Anyone...?

just my 2 cents - A new guy on my crew has a Ridgid set, same price range as my Dewalt 18 volt kit - was very impressed with Ridgid's performance - their Warranty is unreal - lifetime including batteries, couldn't believe it until I read their website - next set for me will be Ridgid from Home Depot