Dewalt 20v max charger and battery

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Spwquebec00

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I discharged my 5.0 A/H 20v batteries until the green battery status light would not light. My charger is good and my battery is good, but because this chargeur is intelligent, for any of the 12V / 20V dual voltage systems, the measured voltage is too low for the charger to start charging for a 20V battery. I have 15.65V DC across the battery. Two high for it to be charged as a 12V.
The battery charger is therefore not able to charge 20V batteries if they are very low. Anybody else wasting batteries because of the design flaw on the charger. I have 5 batteries affected by this, so 500$ of scrap, which isnt really scrap. I drained the batteries too low but would have thought the charger should charge them Dewalt is being obstructive to resolve this so I am looking for others who have this issue and would be willing to challenge Dewalt to rapidly develop a fix.

Not necessarily a class action, but just enough people lobbying to get Dewat to tweak the charger to salvage your investment So it is fit for use.
 

havasu

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Try placing the battery into the charger, then pulling the plug on the charger, waiting 5 seconds, then plug the charger back into the outlet. This seems to reprogram the smart charger and allows your battery to be charged up again. I have a bunch of Ryobi batteries that I was about to toss for this same reason until I found out this trick.
 

Spwquebec00

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Thanks for the input, and I tried your suggestion and various variations, but with no sucess. I have 5 chargers and I am going to strip one down to see if I can fool the circuit to just charge 20V. I will post any comments here for all, unless I get hurt in the pricess, then I shall sue Dewalt under the consumer protection act. My batteries are just out of guarantee
 

kok328

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Don't know about tool battery chargers but, I have been able to bypass the voltage regulator in a floor scrubber charger to force it to charge batteries below the cutoff limit.
Glad I read this post, I have a new dewalt battery that hasn't seen a charge in 2 years now.
I guess I should put it on the charger and see if has become an expensive paperweight.
 

Spwquebec00

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Thanks for the feedback. Apparently, Dewalt is not the only company with this issue..... Ryobi has many issues too. Input on brands such as Milwakee, Makita welcomed.
I start to be suspicious that this could be an 8ndustry scam, designed very cleverly into the circuits to force consumers / contractors to purchase new batteries in a hurry, when there is nothing wrong with them,
Comments please, whilst I figure out how to modify the charger to make it work.
 

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