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Ted Edwards
 
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Default AA battary capacity, Ah (?)

Len S wrote:

One by one, people will realize that NiMH never really lives up to
expectations.


Actually, all 4 sets of 4 (116 cells) NiMH AA's that I have have
exceeded expectations. Sounds like you may have tried very early cells.

gotten years on my Li-Ion Notebook and camera without battery


Well, mine died in two years. This is about average life from what I
have read although a few have done better.

replacement. There is a lot of BS circulating about NiMH (like any
other technical topic).


Li-ion suffers from the same thing such as the statements below

From 1st hand experience:
1) NiMH does have memory effect (they may not call it that, but what
else can you call it when you are told to deep cycle a battery to
"fix" it?


There are several effects in batteries that are eroneously called memory
effect. Li-ion suffers from some of these too.

2) NiMH self discharge is far worse than Li-Ion.


This is true but

something that has been charged withing a few weeks and finding it
dead. If you have NiMH cells, get used to this.


Either you are storing your units in a *very* warm place or your
appliance has an ureasonably high standby current. (This is not all
that infrequent.) Over the winter I do not get out for as many walks as
I would like (asthma) so my GPS sees much less use. I changed batteries
on Feb 2, recharged the dead set and left them in my desk drawer. On
Mar 7, the batteries in GPS died so I switched sets *without* recharging
the set from the drawer. These were in use until Mar 20 (almost two
months since being charged) and delivered their usual approx. 14 hours
running time. I suggest you check the standby current on your
instruments.

4) NiMh performance may, on paper, be close to Li-ion, but in "real
world" electronic products, my experience is that NiMH is far behind.


As you can see, I'm questioning your "real world" experience. My
*measurements* corrolate well with Dave Etchell's in
http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM and the data in
http://www.dp-now.com/index.html

Do not believe that you will get more charge-discharge cycles from
NiMH. Maybe in a contractor's cordless drill that normally gets run to
empty every time, But not in a camera, phone, or PDA, where it's very
normal to partially drain the battery, NiMH hates this, but Li-Ion is
very happy with this kind of use.


Sorry, but this is patently false for NiMH being charged with a smart
charger.

5) Notice that no decent notebook computer or cell phone uses NiMH any
more.


These products also have a high status factor. The average business
persons notebok gets replaced because it is "out of date" not because it
doesn't do the job it was purchased for. Li-ion is a status item.

Ted