Natural Science Forum / Chemistry / Electrochemistry / November 2007

Let us say that you had a SLA Battery that the acid had dried out over time.
And lets say that it was easy to pop the caps on the cells.  And looking
into the cells it appeared that all looked ok except for the lack of
electrolyte solution.

I recently purchased an old Apple Powerbook 180 at the local recycle center.
The computer works great, but the battery is, of course, dead. The machine
won't even power on with it inserted. The battery is a Ni-Cd 6 V 2500 mAh
(model M5653). Opening up the case, I found 10 cells, ...

I'm having some trouble with an eval module for this part.  The system
seems to be in sleep mode, but I can't wake it up per the docs.  I'm
wondering if anyone else has had this experience and found a
solution.

Hi, maybe this topic has been discussed many times, but I've read
different opinion and I'm a little disoriented...
They say that li.ion and li.poly have no memory effect, so there is no
need to discharge them before re-charging...  is it totally true?

Richard Allain and I have just finished coverting this to html:
THE AUTOMOBILE STORAGE BATTERY
ITS CARE AND REPAIR
1922  0. A. WITTE

I think we can all agree that we could always use better and more
durable batteries in our laptops, but I for one can't really find out
what is happening on this front, so I thought I would ask here.
Lithium batteries seem to be the best technology for batteries

Can I determine the effective Ah capacity of SRM27 (85Ah nominal)
batteries by monitoring the terminal voltage when loading with a 8.5 A
load? Is it better to interrupt the discharge periodically, wait 1/2
hr and then measure the voltage to determine the state of charge then

I have been seeing on eBay and the web Li-Ion CR123A-form batteries
said to be 3.0V, instead of the usual 3.7V -- all from China.
When I run the product numbers printed on the batteries (together with
"3V"), the 3.0V batteries come up 3.7V on the manufacturer's pages. Is

I am about to fill some dry charged lead acid traction cells - 2v
920Ah at 10 hr with acid.  The maker recommended 1280 SG acid.
Another user of the same batteries has filled some spare cells,
available to buy if I have a duff cell, with 1285 SG acid.  1280 SG

My spotlight came with a charging circuit that performs as follows
with its 7AH, 12V SLA battery:
-fast charge (0.3 amps) until voltage reaches 14.3V and then shuts off
-resume fast charge when battery voltage drops to 13.0V