Replies

1. 
   JohnWW | Mar 24, 2004 12:23am | #1

   Most of the modern chargers from the better companies have circuitry that turns off the charger once the battery is fully charged.  These chargers usually have lights that blink and then turn a different color and stop blinking when the battery is charged.  Most chargers that can recharge a battery in under an hour also have this circuitry, they'd fry the battery otherwise.

   Simple chargers that don't have control circuitry will shorten the life of a battery if the battery isn't removed once it is charged.

   John W.

2. 
   woodaddic1 | Mar 24, 2004 12:37am | #2

   My 18 volt Makita set indicated to remove the batteries and unplug the charger when not in use.  In otherwords, don't just leave the battery charging until you need it.  I don't know if it has to do with the battery but I don't beleive they have the ability to trickle-charge, like a car battery/charger.

   Ryan

3. 
   PlaneWood | Mar 24, 2004 04:39am | #3

   My PC charger for the 14.4V drill shuts off when the btry's are fully charged.  It senses the voltage and comes back on when the voltage starts dropping.

   Anyone know where to buy the tabbed nicads that are used inside the btry packs?  I replaced some nicads once in one of my btry packs but I had to spot weld tabs onto each btry.   I bought those at a local store and they were expensive.  Replacing 5 nicads was still cheaper than a new pack.

   All of the bad btry's were showing a small negative voltage (at the positive terminal). 

   PlaneWood by Mike_in_Katy (maker of fine sawdust!)
   PlaneWood

1. 
   UncleDunc | Mar 24, 2004 05:01am | #4

   Search the archives for battery repair. I've seen two or three threads on that over the years.

4. 
   tomytinker | Mar 24, 2004 03:24pm | #5

   NiCad batteries will loose charge over a period of time sitting unused (especially in the cold). DeWalt and Milwaukee chargers will charge (flashing light), then when they are fully charged (steady light), they will bump charge (short burst of charge) to keep them up (put your radio on the same circuit and you will hear a 1 sec buzz every 30 sec's or so).

   I've had mine over 3 years, leave them on the charger half of the time, and they are still going strong.

   The manufacturer does recommend not to leave them on the charger where frequent power interruptions occur (starts the charge cycle over and over).

   There are several places you can have your batteries rebuilt for a little more than half the price of a new one, ie: Interstate batteries, battery outlet, discount battery, electric motor repair shops, etc... ). I've done this with my batteries at work.

   Keep smiling :)

   Footer

1. 
   PlaneWood | Mar 24, 2004 05:29pm | #6

   I can repair them, I just need a cheaper source for the btry's.  Interstate wanted something like $7 each for them.  7 x 12 = $84.

   PlaneWood by Mike_in_Katy (maker of fine sawdust!)PlaneWood

5. 
   Dalewood | Mar 24, 2004 06:52pm | #7

   Patk,  About 2 years ago, I received an 18 volt DW cordless drill as a gift.  It came with 2 batteries.  When I finally got around to trying the second battery, it would not charge at all. When I attempted to take the battery back to Lowes, where it was purchased from, the sales guy said it was not under warranty any longer.  The first battery charges ok, but when you leave it unattended in the drill for a couple of days without use, it goes dead as a doornail. I believe the drill was around $200.00 at that time. Needless to say I am not real impressed with DW and I will try another brand next time. Just FYI, my DW charger also has a blinking light that quits blinking when it is fully charged.  Have a good one.

1. 
   JohnWW | Mar 24, 2004 09:11pm | #8

   It would be worth a call to Dewalt, I'd be surprised if they didn't offer to solve the problem even this long after your receiving the drill.  The functioning battery isn't right either, it should hold a charge for weeks.

   John W.

1. 
   Dalewood | Mar 24, 2004 09:49pm | #9

   John,  You are right about that functioning battery. When I first got the drill, the charge would last for a week or so even during use. I may give DW a call.   Thanks for the advice. 

2. 
   tomytinker | Mar 25, 2004 02:30pm | #10

   I have the same problem with one of my Milwaukee batteries. It gets so dead just sitting after a while the charger doesn't even sense it's there and won't come on. The battery guys say this is not uncommon with NiCads.

   NiCads are funny critters.

   Footer

1. 
   Jeff | Mar 25, 2004 03:37pm | #11

   Most of the new battery chargers read the voltage of the battery before turning on.

   If the battery is below the manufacturers set point, your stuck with a dead battery.

   Trick to this is to have an old style charger that will slowly bring the voltage up to above the set point, then you can use the manufacturers charger to finish up.

   I keep a couple of adjustable chargers in my workshop and use them as necessary.

   Also, a volt-meter is handy to test the battery.

   For example:  A 12v battery usually won't charge if below 7v. The battery really dead when it reads 0 - 3v.  3v and above can often be saved by my method.

   Digi-key in Thief Falls sells panasonic battery packs that can be used to replace alot of the standard batteries in tool batteries.  You only need to play around with the fit.

   Biggest problem is often the heat sensor in batteries.  Manufacturers often glue them in and it's hard to remove without damage.

   Jeff

6. 
   Mach70 | Mar 26, 2004 07:58pm | #12

   I found this website when researching the controversial subject of Ni-Cd 'memory' and charging:

   http://www.galaxypower.com/

   Not recommending them--I don't even think they make a retail product--but there is knowledge there.  Particularly interesting is the pricing on their state-of-the-art charging chip.  At the quantities that the manufacturers buy they cost about $1.50!