NiCd cell replacements

The capabilities of the charger are more important. Battery capacity tends to go up as time progresses, but the charge rate is very specific to each chemistry. Not every battery can be fast charged. You don't want to charge faster than the cells can handle. If your charger is on the "dumb" side, it probably just has a timer and puts out a fixed current. I doubt your replacement cells will be lower capacity than the original cells, so the cells will be undercharged if the charger is dumb. But the operating time will not suffer.

You should have a pack assembled by a battery supplier unless you have one of those electro-welders handy. You do not want to solder to batteries.

I have used TNR for nicad packs. They will put the tabs on the ends of the battery pack and do the cell to cell tab connection. I haven't checked their website in a while, but I recall they had some standard battery configurations, i.e. cells in a string with power on opposite ends, cells snaked around with power on the same side, etc. Or you just send them a diagram of your physical requirements. >

Panasonic bought Sanyo, so I don't know if the quality has changed.

Specific? NiCd? You've gotta be kidding ;-)

I have here a Harbor Freight special, 18V cordless drill, NiCd pack. The charger is two diodes (and a transistor to indicate when it's drawing charge current).

Tim

--
Deep Friar: a very philosophical monk. 
Website: http://seventransistorlabs.com

Soldering batteries is not too bad with a high wattage iron.

Now soldering aluminum is impossible, at least for me. :-)

Material cost will be about 8 X 3.00 = $24 for 1700 mAh or

8X .88 cents = $8 for 1300 mAH (I really don't trust anything that cheap.)

You really should listen to what miso says about soldering NiCds or any battery for that matter. It will instantly ruin them.

Stay away from the Chinese batteries. They mostly do not come close to what they advertise for capacity.

1.75"x5/8" = 44.4 mm x 15.9 mm, cheapest source for cells I know of is no they probably don't have the advertised capacity but I've rebuilt 3 or 4 12 V packs for DeWalts and got decent life out of them. From the dimensions it sounds like you have 4/5A cells, 4/5AA are listed as 42.5 x 14.2 mm and the 4/5A as 42.5 x 17 mm so check your diameter carefully. You can get them with tabs already spotwelded on, and then you can solder the tabs together without hurting the cells. Lots of companies rebuild packs, after the third or fourth I was tired of it and now I send them off to for rebuilding. Cost is not much over what the cheapest cells I can find are. Don't worry if the capacity is a little different than the original, depending on how smart the charger is it will either just take a little longer or they may not quite fully charge but I bet you won't be able to tell the difference using the tool.

----- Regards, Carl Ijames

I will be replacing eight cells in a battery for a cordless drill. 9.6 V

The markings did not lead anywhere. DF21NF NiCd

Since there are eight cells in the battery, I think they are 1.2 volt nicads.

1 3/4 X 5/8 are the dimensions if that would help with determining the mAH.

Could someone help me in what would be a good replacement ?

Thanks.

Thanks.

So they are basically lying.

Thanks, I will double check the width.

There is about 3 -4 mm of extra room inside the battery case.(on all edges)

The manual says to charge 3 - 6 hrs., so the charger is probably low on the I.Q.

I will go for non-Chinese brands which is probably the cardboard jacketed batteries that are in the original battery.

Andy

What a surprise.

Nearly all batteries are made in China, but those cheap crappies they sell on Ebay or unreliable online stores are certainly fakes with no quality control behind their manufacturers shoulders.

The point is: whenever something cheap can be easily rebranded to look and be sold as something much more expensive, it usually will be.

This applies to resistors, capacitors, transistors, chips, batteries, memory cards and modules, etc. ...Tubes too! I was bitten in the past by fake metal film resistors and today I have 2 bags of 2SK170GR from diferent Ebay sellers, they are 100% identical at magnifier inspection and work ok, but I had to change their operating current depending on what bag they're picked from because they behave very differently, which could mean at least one bag contains fakes.

I am sorry you did not get your money's worth.

I got 8 name brand NiCads C-type for $17.

After I install them, I'll charge it up and test the run time.

If they don't come close to what was advertised, the seller will get some real bad ratings.

And I'll probably tell 10 or more people too.

andy

If you got 8 REAL C-cells for $17 delivered, I'd like to know where. Do report their measured capacity, ESR and self-discharge rate.

Measure the cells before you install them. Don't remember if you're in the solder-em camp, but that's likely to affect the results...and any claim of defect.

The batteries aren't very expensive from real dealers, and you get the tabs. I tend to avoid ebay for components.

I've used TNR for personal projects and commercial projects. They do good work.

BTW I assume SAFT cells are made in Germany. The Germans don't take kindly to slapping their name on made in China products.

But, I bet it don't keep it from happening.

The sweet spot for REAL C-size NiCd's is about 3.5AH. I've not found them in the $2 range and would appreciate learning where his came from.

I have used MTO

to put new batteries in my DeWalt packs. I had three repacked about 4 years ago and they still hold a charge fine. They seemed eager to please. No relation to the company, just a happy customer. Mikek