Snip  from "Laptop battery" about 7/10/03
 
My daughter was discarding a 5 yr. laptop battery ,12 V.             
3000 mAh,with NiMH batteries, G G 22 A R type,made in Taiwan.        
Measures 4 " wide, 3/4 " thick, 5 1/2"long,about 1 3/8 lbs.          
Not having a laptop,I decided to open it up to see if any            
of the batteries were still good.                                    
 
 I used a table saw to shave off about 1/16 " at a time on the       
end away from the end with the electrical contacts.                  
Once an opening showed,it was easy to put in a screwdriver           
and pop the top off.                                                 
                                                                     
 From the back end,I see 5 bulbs on the left,with openings in        
the case.I guess these denote the degree of charge.                  
I see 10 batteries, 2 1/2 " long,( AA=1 7/8")in 5 rows of 2 each.    
They were 21/32 " O.D. larger than an AA of 18/32 ".                 
 
End Snip
 
After some experiments,I decided to recharge them in my NiCd 
charger (GE BC8B ),even though some articles warn against using 
it on NiMh batteries.These extra long batteries barely fit .
For the 1st hour,they were a little warm and 
the voltage was below 1.2 Volts.At the second hour,they were 
cool and at 1.25 V. After the 3rd hour,they were still cool and 
at 1.37 v.After another 1/2 hour,they still read 1.37 v. Then I 
quit.Checking the next day,after overnight in the refrigerator,
3 were dead,but the others still at 1.37 v. .One article I've
read said that the final voltage could be 1.45 volts.The battery
pak was rated at 3000 mAh.
 
Now what can I use them for? I have some portable cassette-radios
that used 2 AA batteries for 3 Volts.Maybe I can put the 
batteries into a cell holder and connect them to the radios 
through the power jack.I didn't find any holders for these 
batteries so I made my own.I had some cell holders for 2 "C" 
cells (2 1/2 "by 2 3/16").I used a table saw to cut them in half 
by putting masking tape about the center and used an worn 8" 
table saw blade with the blade on backwards for cutting plastic.
The plastic edges were slighty burred and easy to sand off.
 
Then I cut some softwood pieces 3 1/4" by 2 1/4",drilled 1/8 " 
holes in the plastic and 3/32 " holes into the wood and screwed
the cut plastic onto the wood.The batteries had room to move
so I found some plastic, cigar tubes and cut 1 3/4 " pieces
to slip over the cells.Still a little loose.Added a 1 4 "
strip across the center of the assembly.Looks OK now.
Next trip to Home Depot,I'll look for some Tygon tubing
for a tighter fit.
 
Trying to connect into the external power jack on the radios
was a problem.There are NO standards.I had 3 different radios
with different plugs for 3 Volts.For the Sony,the plug was 
3/32 " with the outside Negative polarity.For the Optimus 
(Radio Shack China),the plug was 9/64 " with the outside at 
PLUS polarity.For the Gran Prix (Indonesia),the plug was 
13/64/",unknown polarities.The best way of checking polarity
is to connect the batteries to the cassette with a tape
in it,run for 3 seconds-Stop-check the tape for abnormal
operation.
  
I understand that you have to age new NiMH batteries properly.
You have to further discharge the cell to a lower value 
several times after each use.With these rebuilt cell holders,
I can use a resistor to take the voltage down to about 0.5 V.
 
Now when I go out on the back porch ,watch the birds feeders 
in the day,or have a cigar at night,I can play tapes from
talk shows and fast forward through the commercials and
trivia without the batteries dying on me.
 
I still use the NoCad "C" batteries from defective powerpaks 
for portable tools in "C" battery holders for some radio
uses.Just shave off an edge on a table saw to open.
 
I keep all batteries in the refrigerator in plastic bags.
 

--- Maximus 2.02