Replace batteries in cordless drill battery pack

[Tinbendr]

I have a Craftsman 14.4v cordless drill and I was contemplating replacing the batteries myself instead of just replacing the pack.

Is there anything I should consider when purchasing replacements?

I plan to use the same type of battery; sub c, NiCd.  But I notice a lot of different power ratings.  Some 1700mA, some 2000mA, and finally 2400mA.  I was leaning toward the highest rating so as to get the best performance out of the pack, but I'm not sure if the charger would be able to manage it properly.

Thanks in advance.

[Bruce S]

Grab the charger pack and make sure it would handle to extra current rating.

The output of the charger will dictate the most it can handle for a given time frame.

IF it is one of the better charger packs, it'll charge even the higher rated ones as it will not turn off until it sees a known voltage slope for the NiCds.

If it is a straight shot plain jane charger, it'll work too, just will take longer to charge up the entire pack.

There's been a few people who've done this. As a word of caution, stay away from NiMh, they do not charge the same way, even if they might be cheaper with a higher current rating.

Also make sure you have a GOOD HOT solder iron/gun, heat will kill these quick. The tin tabs should be soldered to as quick as possible.

Best of luck

Bruce S

 

[dnix71]

I had a college dorm mate who put himself through school partly by repairing nicads packs. He would test each cell and only replace the one/s that were bad. He advertised for any rechargeable appliance and had plenty of customers.

I wonder how much longer the US will allow NiCads to be used. The cadmium is toxic, and NiMH cells seem to be much more common than they used to. NiCads can put out more current, though.

[Bruce S]

NiCds will be around for a long time. They are completely recyclable, are usable for 2x the charging cycles as NiMh and are just as easy to charge control.

Cadmium is toxic when handled wrong, or worse just dumped into the enviroment.

I still rebuild units that belong to me and neighbours.

For safety, I rebuild and replace ALL cells, since bad ones can severly hurt the others. Possibly causing them to reverse polarity.

There is getting to be as many recyclers looking for spent NiCd batteries as there are WVO users.

Cheers

Bruce S

[Norm]

I have 2 of what you have, don't be so hasty to

replace those batterys now if you have the smart

charger and your battery is low 2 lights may go

on indicating it is on slow charge ....you can

fool it by quickly plugging it in.... barely

unplugging it....then quickly plugging it back in

it may take a few tries before you get the knack

....but it does work.

 In my case on one of them that I had, the pak

had built up crystals blocking the flow of

current,took the battery pak apart and took my

10 amp 12volt battery charger and zapped each

cell about 3 times.

  There are two types of 14.4 Craftsman paks....

they have different numbers one is for the

 smart charger fast charge and the other is for the

slow charger if you try to charge the slow charge

battery with the smart charger ...the green light

will come on but it will slow charge.....

On the other hand if you try to charge a fast

charge battery with the slow charge it will burn

up ....at least mine did....

 

[Norm]

Just stating my experience.....mileage may vary

............

[Tinbendr]

Grab the charger pack and make sure it would handle to extra current rating.

Ahh yes, I'll check.

IF it is one of the better charger packs...

It is supposed to be the two step charger.  Fast charge, then tapering off.

As a word of caution, stay away from NiMh, they do not charge the same way...

Yes I was aware of different types requiring different BMS (Battery management system), hence the reason I'm staying with NiCd.

Also make sure you have a GOOD HOT solder iron/gun...

THANKS! I've been needing an excuse to buy an iron.  

[Tinbendr]

don't be so hasty to

replace those batterys now if you have the smart

charger

I do have the two step charger.  

I have two of these packs (One for the drill and one for the light.)  Some time ago, I purchased these replacements at the same time.  One of these charged fine, while the other double-lighted on me.

... it may take a few tries before you get the knack

....but it does work.

I'll have to try this.  Thanks!

[Norm]

I started out with what you have...batteries

seemed to be going so they had the same drill,

small slow charger and two battery paks on sale

for $49.95....figured that was cheap....they

looked the same?....didn't know that

different numbers made a big difference.

Live and learn......

[Tinbendr]

two battery paks on sale for $49.95....figured that was cheap....

This is actually my third series of paks.  Like you, they were always cheaper to buy the paks than to replace the cells.  But I've found a source (Ebay) that has 24 cells for about $35; the same cost as one pak.

Thanks for the comments!

[ghurd]

That's not cheap, if you can prove you know what you are doing and will not throw them in the trash.

[Bruce S]

WHAT $35 for 24 cells?

Gents, I'm in the wrong biz!!

I've been swapping used , but perfect cells , that need "reconfiguring" for advice from the configuring guru ( commonly known as NORM )

sorry Norm couldn't keep your secret anymore

Norm go hide those packs, we're about to surpass Ghurd as dozen aire's )

Do a google of Norm's posts and see if that's do-able by you and let us know. We may be able to help save a few $$.

No slam on you knowledge about batts meant earlier, just don't know enough about your abilites yet.

Bruce S

[Norm]

Bruce, almost completed except for end pieces....





the two on the left 12volt 5amp/hr cordless scooter batt  paks. 40 cells each $1.45 per cell

.....hmmmm!

  (choke...cough...gasp !)

charged with solar VW panels....pedalpowered

generator...

[Tinbendr]

Grab the charger pack and make sure it would handle to extra current rating.

Here's the label.





From what I understand about chargers, this will charge at the 2.2 amp rate, correct?  The capacity of the battery shouldn't be a problem for the charger, right?  It will just take longer to charge.

[spinningmagnets]

I recall an E-biker who made his own battery packs this way by stacking C-cells in PVC tubing that was mounted horizontally on both sides near the top of his frame. When the batteries get warm, they will expand and get slightly longer, so perhaps put a spring connection on one end to allow for this.

I have heard when soldering tabs on batteries to get a good connection that can handle the amps, if the soldering iron isn't quite hot enough, you have to hold it on longer, and some of the heat can get down into the battery chemicals, so very hot and fast was recommended.

Related to that, here's a very long discussion on making a home-built capacitive discharge "spot-welder" for ~$100:

http://endless-sphere.com/forums/viewtopic.php?f=2&t=2633

"Red meat isn't bad for you,...but green meat, now THAT'S bad for you" -Tommy Smothers

[Tinbendr]

making a home-built capacitive discharge "spot-welder" for ~$100:

Hey, I appreciate that link.  I've been looking for a spot welder, but for a different project.  I'm sure I can adapt it.

[independent]

I've charged my batteries with a small solar panel and one of ghurd's controllers. Had to modify a charger so I could get a few amps into it (not usable as a mains charger now). Think of a small solar panel as a constant (not that constant current device. Keep the amps to C/10 and you'll be fine.

[Bruce S]

Tinbendr;

 Soory took a mental break for a while, didn't notice the response.

The answer is yes, it'll handle the extra load.

Using the C/10 math your batteries will actually live longer if you add higher density batteries. If it does indeed use the full 16V @2.2A, then for it to truly use the C/10 for proper charge then you should be able to add  up to a full 22Ahr of battery before it starts to get too loaded down.

The 16V is to get it over the 14.4V and will come down to battery terminal voltage just a soon as you connect a battery pack.

Hope this helps;

Bruce S

[Tinbendr]

OK thanks.

I hope to order in the next couple of weeks.

[Tinbendr]

Finally ordered NiCd 2200mA replacements.  The packs were starting to last only 10 minutes.

Here is the pix midway through.

I didn't take the time to make the spot welder.  I just soldered them.  It took about 1.5 hours per pack to solder 12 batteries together.  What a pain!  Tedious work.  On the first pack, I got turned upside down and started building the pack backwards.  Other than that, I really didn't have any trouble.

On the second pack, I got my Dremel out and scuffed the tabs were I was going to solder.  The solder sticks much better.

After a fresh charge the packs were up to standards again.  Yipee!

After reassembling I took and threw the old ones in my neighbors fish pond.  (YES, I'M KIDDING!  Our waste management has a twice a year battery turn-in, so, in the box with the other undesirables.)