Replies

1. 
   BILLKUNERT | Oct 25, 2002 09:05pm | #1

   If a nicad is discharged too far it can reverse and won't accept a charge.  applying a high current to it will sometimes reform it but not always.  Instead of buying a new pack why don't you go to a hobby shop and get some 1300 to 1800 mah nicads with tabs and build your own pack.  R/C electric cars use these as power cells.  Sanyo and Panasonic both build good cells.  The cells should be available for less than $3.00 each for 1300mah cells.  Be sure to use rosin core solder and don't get the cells too hot. It can save you some money and maybe give you a better pack than you originally had.

   Regards

   Bill

2. 
   Trees2dust | Oct 25, 2002 10:04pm | #2

   Hi Mike,

   Zapping the NiCds with high current does work, but most likely the cells will go bad again in a short time.  I have used a car battery to zap shorted cells.  What happens is that dendrites grow within the cell (kinda like stalactites and stalagmites in a limestone cave) and short the cell out.  The high current blows away the dendrites and the cell works normally again.  The bad news is that the dendrites grow right back and you get a shorted cell again.  I'm not sure if I got the terminology and spelling right, and the safety folks might get upset about the use of a car battery, but...  If your power supply is not enough to unshort the cells, a safer option than the car battery is to use your power supply to charge a large capacitor (10,000 microfarad or so) and use that to zap the cell.  If your leads are thick and short, the capacitor will put many more amps into the cell than your power supply is capable of.

   With that said, what I did was to go buy another drill kit.  It came with 2 batteries, charger and drill- for less than the price of the batteries alone.  Not as much fun, but less hassle and guaranteed to work.

   Rick

3. 
   bobpowers | Oct 25, 2002 11:13pm | #3

   Mike,

   I just sent two 14.4 batteries from my drill to http://www.primecell.com.  For about $40 each plus shipping, they rebuilt them and for some strange reason, my drill runs better than new.  Maybe my memory is slipping, but it really seems better than new.

   Bob

1. 
   PlaneWood | Oct 25, 2002 11:40pm | #4

   I just went to Interstate Battery and bought 4 new ni-cads and already have them in and charging.  Cost was $5 each.  Still a rip off, but less than paying PC $70.

   Funny, but about 2 years ago I threw away about 40 or so nicads of this same size!  Salvaged them out of computer equipment 10 years ago.

   PlaneWood by Mike_in_KatyPlaneWood

1. 
   Andrew | Oct 25, 2002 11:57pm | #5

   Hey Mike, I've been having similar problems with my PC 14.4. how old is yours? I bought mine a little over a year ago and I recently noticed they weren't holding their charge well. now my charger has confirmed that the batteries are weak i called up the guy i bought it from and told him about it. he said just to bring the drill back and he'll either fix or replace it. batteries really are a ripoff, but there's not much anyone can do about it. other than the batteries I really like my pc. after this though i'm thinking that i'll go and get a milwaukee corded drill to add to my tool collection.

1. 
   PlaneWood | Oct 26, 2002 01:11am | #6

   Andrew -

   I've had mine about 2 years and usually cycle each battery pack each day.  That tells you how much I use it!  I resisted getting one for a long time, but now can't live without it.

   I recently replaced a cedar fence using screws instead of nails.  The good battery pack would do 30 feet of section before dying.  The bad pack would last just long enough for the good one to get recharged!

   PlaneWood by Mike_in_KatyPlaneWood