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[teckno_no1]

sony se us18650v  cell have nominal voltage of 3.7 volt and 1500ma this give a 5.55 wh, output 15Amp discharge

sorry

[golden valley const.]

Teckno,  even though watt hours seems like the most true and accurate measure of a batteries capacity, it's not the whole story.  This is because w/h are usually measured at a very low discharge rate.  The measurement will not be the same at a high discharge rate.

So while a Sony se us18650v cell may be rated at 5.55 w/h, it might be just half of that when drained at a 15 amp rate.

This can be illustrated by comparing two tools.  One might drill more holes with any bit under 1", but the other drills more with any larger bit.

If we wanted a really meaningful measure of tools for comparison, we'd have "watt hours out" at low, medium, and high loads.

[sparkey]

what does the 12v Max use?

[ToolGeek]

Go to the "a look inside" forum. Dewalt 12v max uses Sanyo.

[HaTaX]

Well, here goes my first post here!

I haven't seen much info out there on the Skil 18V pack (SB18B-LI) that is a drop in replacement for the Ni-Cads that are known for being horrible in every regard.

I decided to pick up one of the kits from Home Depot as it was only about $90 from the online store and I have quite a few of these tools floating around including a full sized 7.25 saw that has always been a favorite of mine.  The tools were all in great shape but a small amount of neglect to the batteries have resulted in 4 dead packs.

Since I've looked at rebuilding the Ni-Cad packs as well I was curious which cells they used in these packs and have taken some pictures to share with the thread here.  Looks like this is where you're getting the Skil name, looks to be a well designed product and then they get the lowest rated cells to do the job.  When these cells are getting weak I think I'll replace them with some 25-30A units and see how that helps torque and such.

Great info here!  Thanks for giving me a reason to open these things up. 

[DEWALTDUDE]

Thanks for posting these in. I've never taken a Skil cordless tool apart. Bosch currently uses Samsung cells, and being a partner in crime it's no surprise to see Samsung cells being used here. Samsung is the creater of Milwaukee's Red-lithium a battery that finally caught Milwaukee up with the rest of the competition in my opinion.

I don't think rebuilding any lithium pack is a good idea, unless your simply replacing the cells with the same type of cell. Each brand has it's own unique charging method, and as such could be dangerous... or the charger may not even charge them?

If you move forward with the rebuild, post in a follow-up.

[HaTaX]

Well I've ordered a second charger and battery pack and that may be one I test a rebuild on.  Then I can keep the old set of cells on a shelf for reuse.  I noticed that when using them in the sawzall they get warm and shut down after about 5 minutes of use. (Just cutting up some branches in the lawn)

Looking at this chart:
http://www.samsungsdi.com/battery/cylindrical-rechargeable-battery.jsp

I see the batteries are the 10A models, yikes... Not a whole lot of current available from those cells...  My plan was to replace them with the same series of cells, just with a higher current draw rating.  If I can get my hands on some INR18650-13R cells that'd be great, but anything looks to be better then what's there now.

If I tear it down and replace the cells I'll post up the work here. 

And as an aside, a high end RC battery charger / conditioner does WONDERS for Ni-Cad cells that look dead.  I made a modification so I could get half of the pack on the charger at a time and it has brought most of my Ni-Cad packs back to life.  Well, if you consider life being 5-10 minutes of 100% power before they fold, still better then not taking a charge at all.

[The Red Baron]

big disappointment!

 Dewalt that not only uses A123Systems

[DEWALTDUDE]

I'm not sure I understand what your saying?