Cordless drill batteries

[Struts 'N' Stuff Auto]

Also if your planning on using the 16.8V
charger I doubt it will charge the 19V battery to it's full potential. The 16.8V charger will max
out below 19V so the 19V battery will never fully charge. Now if you only charge the 19V battery
to 16.8V then your ok.

Thats not how it works though!
All cordless rechargeable Ni-Cads are a bunch of 1.5 Volt batteries in series to make up the voltage.
The maximum battery voltage is determined by how many batteries charging to their max capacity.
A 19 Volt system uses 13-1.5 volt batteries in series.
A 16.8 Volt system uses 11-1.5 volt batteries in series.
All chargers put out at least 3-4 volts more Voltage then the battery Max voltage to charge the battery pack.

My Craftsman 13.2 volt system uses 9 batteries in series and the charger actually puts out 17 volts, when the batteries are fully charged, I have just over 14 volts.

[Bsuds]

I looked online and Sears sells their battery packs for 39.95...pretty much all voltage types the same price. That's not too bad.

[SC1]

If they are NiCad packs, try resurrecting them, if you have a higher amp battery charger or a welder.
I did this to my ryobi 18volt packs that are old and and on there way out, this technique worked well, and I'm still using the packs today. It's obviously not going to work on every pack, but its worth a shot before you buy new ones.

http://www.youtube.com/watch?v=ENmAJ2GOAMY&eurl=http://blog.makezine.com/archive/2006/12/how_to_revive_n_1.html?CMP=OTC-0D6B48984890

This is a write up on Nicad's, that has a good explanation of the reviving process.

http://www.hamradioindia.com/HRI-THEOR/Funda-DC/nicad.htm

[OffRoad]

Also if your planning on using the 16.8V
charger I doubt it will charge the 19V battery to it's full potential. The 16.8V charger will max
out below 19V so the 19V battery will never fully charge. Now if you only charge the 19V battery
to 16.8V then your ok.

Thats not how it works though!
All cordless rechargeable Ni-Cads are a bunch of 1.5 Volt batteries in series to make up the voltage.
The maximum battery voltage is determined by how many batteries charging to their max capacity.
A 19 Volt system uses 13-1.5 volt batteries in series.
A 16.8 Volt system uses 11-1.5 volt batteries in series.
All chargers put out at least 3-4 volts more Voltage then the battery Max voltage to charge the battery pack.

My Craftsman 13.2 volt system uses 9 batteries in series and the charger actually puts out 17 volts, when the batteries are fully charged, I have just over 14 volts.

Of course there's more to take into consideration than just voltage. A car battery (lead acid) charger charges at a set voltage and the amperes vary during the charging cycle with a dead battery drawing more amps than a charged battery.

Now take into consideration that the resistance of 19V and 16.8V batteries are going to be different due to the additional cells in the battery and you can see that the 19V and 16.8V battery will draw different currents and charge at different rates when connected to the same charger.

If it will work or not depends on the charger. Charging a lower voltage battery with a higher voltage charger could leave you with a melted battery. Charging a higher voltage battery with a lower voltage charger could leave you with a melted charger.

If it were me, and I didn't care about the battery or charger, I'd try it but would keep a close eye on them watching for overheating/melting.

[Born_again]

An insider's tip to all: The DeWalt 14.4v is the dogs nads. Anyone messing about with the common or garden brand 18v, 24v drills can replace the batteries within the battery pack themselves, providing they have a high wattage soldering iron(min. 60W) and a bit of technical ingenuity. Replace the 1300mA/h batteries with 2300mA/h ones. Do not be fooled by drills offering higher voltage over a 14.4v unit, it's all B/S marketing ploys--aimed at boys wanting 'bigger' toys. You get what you pay for.

[DANSPEED]

Thats not how it works though!
All cordless rechargeable Ni-Cads are a bunch of 1.5 Volt batteries in series to make up the voltage.
The maximum battery voltage is determined by how many batteries charging to their max capacity.
A 19 Volt system uses 13-1.5 volt batteries in series.
A 16.8 Volt system uses 11-1.5 volt batteries in series.
All chargers put out at least 3-4 volts more Voltage then the battery Max voltage to charge the battery pack.

My Craftsman 13.2 volt system uses 9 batteries in series and the charger actually puts out 17 volts, when the batteries are fully charged, I have just over 14 volts.

I disagree.

The cheapest battery charger is a transformer diode only type. The transformers output
voltage is chosen to be close to the fully charged battery pack. These chargers have little
or no short circuit protection and will usually take hours to completely charge a battery pack
because once the battery voltage nears the input voltage the current drops off to almost zero
and the internal resistance of the battery takes over.

A better design is a constant current source charger where the charging current is constant over
the entire charge cycle. These types of charges may or may not have a short circuit protection
built-in but at least a near depleted battery pack won't receive a large initial current. These
types of charges either stop charging when the battery pack reaches full potential or when
a timer cycle is complete. Some even switch to a trickle mode.

The best battery charger is a variable current source type using an integrated circuit that monitors
not only the current to the battery pack but also the temperature of the battery pack. It's when the
battery pack is near depletion or near full potential the charging current is most critical.

I've designed many battery chargers in 30 years.

So Struts 'N' Stuff Auto, depending on the 16.8V battery charger type used to charge a 19V
battery pack I still say it might not fully charge it.

[Struts 'N' Stuff Auto]

I disagree.

The cheapest battery charger is a transformer diode only type. The transformers output
voltage is chosen to be close to the fully charged battery pack. These chargers have little
or no short circuit protection and will usually take hours to completely charge a battery pack
because once the battery voltage nears the input voltage the current drops off to almost zero
and the internal resistance of the battery takes over.

A better design is a constant current source charger where the charging current is constant over
the entire charge cycle. These types of charges may or may not have a short circuit protection
built-in but at least a near depleted battery pack won't receive a large initial current. These
types of charges either stop charging when the battery pack reaches full potential or when
a timer cycle is complete. Some even switch to a trickle mode.

The best battery charger is a variable current source type using an integrated circuit that monitors
not only the current to the battery pack but also the temperature of the battery pack. It's when the
battery pack is near depletion or near full potential the charging current is most critical.

I've designed many battery chargers in 30 years.

So Struts 'N' Stuff Auto, depending on the 16.8V battery charger type used to charge a 19V
battery pack I still say it might not fully charge it.

Well, we weren't talking about building battery chargers, we were discussing batteries!
I just explained what I found out from the testing I did on my battery packs,chargers, etc!

So, maybe if someone has a digital multi-meter, a couple of cordless drill batteries and a charger, we might be able to learn a bit more about what the charging voltage is compared to the actual max battery output voltage, all in fun of course.

[Inate]

The best battery charger is a variable current source type using an integrated circuit that monitors
not only the current to the battery pack but also the temperature of the battery pack. It's when the
battery pack is near depletion or near full potential the charging current is most critical.

Truth.

Most drill pack chargers are set to fixed voltage charging and most of them do not charge in bulk(absoprtion) mode, which is where they fail. Ideally a Dewalt 14.4v(12x1.5v cells) pack will be discharged to 9.6v(12x0.8v) then the packaged charger SHOULD charge the back to 19.2(12x1.6v).
The reasoning behind the higher voltage is to bring the internal resistance in the cells down so they may accept the amperes being input from the charger.

So what does this leave us? Well, having a 16.8v pack, and somehow jerry-rigging your Dewalt 14.4 charger to charge it will leave you with a constantly undercharged battery pack(16.8v needing a full 22.4v charge input). It will work, the beauty of DC is that it just plain works. There are a lot of drill chargers out there that accommodate multiple drill pack voltages, usually if they do it is labeled on the charger itself somewhere or you can find it in the tech manual(found online). I have a pack here(14.4) that the charger will work with 9.6v packs to 19.2v packs and properly charge them.

I don't think I really answered any questions, but maybe this will help someone with a project of theirs.

[DANSPEED]

Most drill pack chargers are set to fixed voltage charging ...

That's what I was getting at, a fixed voltage. My Craftsman cheapo 18V battery chargers
no load output voltage is 21V meaning it will never charge a battery pack larger than 21V.
This is only 3 volts above the 18V battery pack value. So if the 16.8V battery charger in
question has a no load output voltage of 19.8V it will never fully charge the 19V battery
pack.

[sunshine11]

This post was removed by the author since it did not meet posting rules (contained all caps)

[sunshine11]

This post was removed by the author since it did not meet posting rules (contained all caps)

[Bsuds]

Hey! I saw something on YouTube about rejuvenating rechargables by shocking them with a stronger voltage. This guy was using a 16volt welder current...?

ANYBODY DONE THIS or research?

Any ideas?

Buy new batteries on E-Bay.....cheaper and safer. ($50. or more) cell phone batteries for less than $8 including shipping.

[mosound]

yes it will work but most often they will not match up they always seem to make a small connection difference so the battery will not attach !

[Bsuds]

yes it will work but most often they will not match up they always seem to make a small connection difference so the battery will not attach !

If you are referring to buying batteries from China I have purchased many ( for Cell phones, cordless phones, cameras, etc) and never had a problem.