Rebuilt cordless tool batteries

[mapleman]

My father has a 24V craftsman drill set that we bought maybe 10 pyrs ago. The batteries are pretty well shot. They will not take a charge, no matter what trick I try. They did that once maybe 5 yrs ago, and I tricked them. Got another 5 yrs. But they seem to be toast now. And of course, it is hard ot find replacement bats for these big boys. but they have so much juice, this drill is hard ot discard.

Has anyone ever tried or even heard good reviews of rebuilt batteries? I am interested in something like this:

cgi.ebay.com/Battery-CRAFTSMAN-24V-NICAD-11035-27125-911035000_W0QQitemZ390123669382QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad52ec786

this is for the 1.5AH variety. They have a 2.0, but almost double the price... What do y'all think?

thanks for the help, john

[Joe Lyddon]

Can you take the battery case apart to see what is on the inside?
... normally, you will find a few smaller batteries in Series & Parallel various ways to get the job done.

If so, you could then search for those type of Nicads & see if it would save you much to rebuild it yourself.

This is assuming you're savvy around electronics & soldering irons, etc.

[lpdicecco]

Mapleman,
I just recently had my Bosch battery rebuilt. This was done at the local Interstate Battery place. Cost was about $40.00 versus $70.00 to $80.00 for a new one. Hopefully their is a place near you.

[sawduster]

Lots of times the actual batteries inside those are standard sizes, i.e. C, D, AAA etc.

[mapleman]

Thanks guys.
Joe,
I could basically wire a house if needed (would have to consult others for code-compliance, but it would work). DC - heck no. No clue.

Larry,
thanks for the idea. i will check and see if i can find a semi-local place. I went to school at UVM for a year -- you are lucky to live up there. It is a great area. I miss Church Street - what a place.

Jerry,
Like I said to Joe. I have no clue

thanks for the responses guys
john

[imahic]

Not sure where you are located but check to see if you have a Batteries Plus in your area. They have batteries for just about anything you can imagine. I needed a laptop battery a few years ago and found the one I needed there at a much cheaper price than ordering from the manufacturer.

DC voltage is really pretty simple to understand. I bet you would be surprised if you check it out. Seems like I heard somewhere of a place you can send batteries to and have them rebuilt but can't remember where I saw that or how good it works.

[Joe Lyddon]

DC is probably much simpler than AC!

Series connections:
Connect several cells (batteries) together - to next +, that - to next +, etc. At end of string, you have a - and + at each end...
Total Voltage will be the SUM Voltages of each cell ...and the
Current (power) will be the same.

Parallel connections:
Line up several cells so they have all - sides on the same side... Now connect one wire to All -'s of all batteries... and connect one wire to all of the +'s of all batteries. Now, you have one - and one + for the bunch!
Total Voltage will be the same as the Average battery voltages ... and the
Total Power (current amps) will be the SUM of the power of each battery.

[jon1941]

hi
this place will rebild your old batteries
www.primecell.com/index.html

[rrich]

Generally speaking, if you can pick up a soldering iron without getting third degree burns, you can rebuild most batteries.

As has been said previously, most commercially available tool batteries use generic cells that come in standard sizes. (D, C, AA or AAA)

When you take the battery case apart, just note how the cells inside are interconnected. In all probability, an 18 volt battery pack will have 12 cells wired in series. The plus of one battery connected to the negative of the next. In the 18 volt battery pack there may be several stings of 12 cells wired in parallel.

When you purchase the rechargeable cells there a few constraints that must be followed. If the cells are Ni Cad they must be replaced with Ni Cad. NiMh and Lithium must be replaced with like cells also.

The cells have a charge holding capacity. This capacity is expressed in Ampere Hours (AH). A Milliampere Hours (MaH or M-AH)) are 1/1000 or .001 of an AH. There are several AH capacities per each physical size. If your battery has internal electronics (Usually NiMh and Li-Ion) it is best not to try to change battery capacity.

There are places on the web that sell the cells that go into battery packs. These places can sell batteries if you tell them the application, (e.g. Norelco Razor, etc.) dimensions or the number stamped on the side of the cell. The batteries for my Norelco were less than $10 on the web or $40 at the store that sold the razor. It was a $29.95 razor.

When soldering your cells, there are two things to be concerned about.

The first is the heat of the soldering iron. Quick on and quick off. Remove the residual flux with isopropol (Drug store rubbing type) alcohol. Use a lot of alcohol and a small brush. The alcohol will not affect the electronics. The cleaner that you get the battery pack the better.

The second is electrical current. Usually the cells in battery packs are connected with a flat metal strip soldered to the ends of the cells. It is best to re-use these metal strips as it makes re-assembly of the battery pack easier. Remember, that the metal strip has the current carrying capacity of an 16 Gage wire.

Remember that an ordinary "D" cell can supply about 40 Amperes. Not for a real long time but still 40 Amperes! If you doubt this, take your VOM on the 50 Ampere scale and connect it across the "D" cell. You will be surprised.