Dewalt 18 volt batteries not charging

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ultimatehandyman
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Dewalt 18 volt batteries not charging

Post by ultimatehandyman » Thu Jul 05, 2007 3:03 pm

I Now have 3 Dewalt 18 volt batteries that will not charge ::b

I thought that they would be good for at least 1000 charging cycles, but I have hardly used mine and doubt it some of them have even had 30 charging cycles and now they will not charge at all :roll:

I did use the fast 15 minute charger for most of them, perhaps this has damaged them?

Either way I am not happy about this as I have a bosch 12v twin pack that has probably done 1000 charging cycles and all three of those batteries are still working fine!
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Post by big-all » Thu Jul 05, 2007 6:03 pm

i have 2 dewalt batteries that are around 10 years
2 at 3 year old and 3 at 6 months old

the 10 year old batteries are probably holding around 40 to 60% charge

i personaly dont like rapid charge as i suspect it must effect the bateries

have you tried a different charger [hopfully 1 hr] because they are electronic the charger may be picking up on the battery condition and refusing to do a charge where as a a slower charge may be ok

i personaly would suspect the charger is over sensitive for some reason as you dont expect 3 batteries to pack up unless thats the pay off for quick charge


ooo and my dewalts are all 2/ah not used on a daily basis but all batteries put through a full cycle every 2 or 3 months
we are all ------------------still learning
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Post by ultimatehandyman » Thu Jul 05, 2007 6:06 pm

I have varying AH batteries from 1.6 to 2.4

The ones that have packed up are all 2.0 ah or above, the last one that packed in was charged the last few times with the hour charger as I refuse to use the 15min charger anymore.

Might have to try that trick with the mig welder :grin:
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Post by big-all » Thu Jul 05, 2007 8:13 pm

i am seriously tempted to buy the 3/ah nicad cells off e bay and construct a battery pack solderd together with copper connections would cost around £25 to 30 for a new battery

and for any body trying to dismantle a dewalt battery
when you have all the screws out you need to push on the battery contacts to free the battery connected to it
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Post by Jaeger_S2k » Fri Jul 06, 2007 12:23 am

NiCad cells have a memory.
If you regularly discharge for say 1 hour (over the work period) and then recharge they can begin to believe they only have 1 hours worth of life.

Or if you remove before full charge regularly they believe they are fully charged at the point you've removed them.

They can be 'Brain washed' by completely discharging them, but then another fine feature of NiCad’s raises it's ugly head, they can go into 'reversed polarity' where you discharge below the minimum and they swap over, positive becomes negative and you know the rest.

The really should be cycled regularly and the electronic charges should have a couple of settings on them to do this, have you read the instructions?

Some are press and hold a button before placing the battery on the charger this sets of the electronics diagnosing the battery and doing to it what it needs.

You could also try connecting a small bulb to the terminals and allowing it to dim, but not go out (reverse polarity) and then recharge, if you do get it going again, it's best to discharge in one go, recharge. Repeat a couple of times. That can bring a dead battery back to reasonably full service.

Used to happen a lot with our (Ham) radios.
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Post by uncle buck » Thu Jul 26, 2007 9:18 pm

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Post by Only-Me » Thu Jul 26, 2007 9:58 pm

I got a 14v makita that is about a year and a bit old..........with 3 batteries.......none of them hold there charge for long, :cb constantly charging them up :|
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