Maker Pro
Maker Pro

Unused Li-ion battery pack

N

N_Cook

How to store to retain it for possible future use?

deliberately discharged and then unattended outside of pc
charged up in pc and then unattended outside of pc
charged via otherwise unused pc once a month? 6 monthly ? yearly ? and then
removed from pc
stored in a fridge? or just a cool dry place or a warm place
 
G

Geoffrey S. Mendelson

N_Cook said:
How to store to retain it for possible future use?

deliberately discharged and then unattended outside of pc
Will destroy it.
charged up in pc and then unattended outside of pc

Yes.

If you have an antistatic bag and a moisture abosrber, put them in it and
seal it. Keep cool, but do not freeze (as the UNIX fortune program used to say).

In case any one wonders, the cells themselves are not affected by static,
but the electronics inside the battery pack are.

If you are the cautious type, place the anti static bag inside a sealed
zip lock bag. If the cells leak, the electrolyte is extremely corrosive.

I have no proof, just a feeling, but I would not place them in bag and seal
it using a vacuum food sealing system. The cells are designed to not leak
at seal level air pressure, not a vacuum.

Geoff.
 
W

William Sommerwerck

Anti-static bags are conductive. Not like metal, but they conduct. Make sure
the battery's contacts are covered.
 
J

JW

Anti-static bags are conductive. Not like metal, but they conduct.

Especially the cheap ones that motherboards and such come in with the
crosshatch patterns on the outside of the bag. Never put a motherboard
down on the outside of one or you can discharge the CMOS battery if left
long enough.
 
G

Geoffrey S. Mendelson

who said:
That was one reason for the selection to be available. Unfortunately
(as I mentioned earlier) laptop manufacturers have one objective -
maximum runtime for minimum cost.

And weight. If cost and reliability were more important, they would use
nickle metal hydride cells. The cells are almost indestructable, easy to
charge, have no reputation of early failure or catching fire, and so on.
They can be reconditioned by draining them completely, which they actually
seem to do well with unlike any of the lithium cells.

Somewhere along the way, people decided that expensive lithium cells were
"in" and nickle metal hydride cells were for flashlights and $10 MP3 players.

This is IMHO one of the great failings of portable device design in this
century. What surprises me is that no one has picked up on this in the
"climate change" crowd, lithium cells use rarer materials and are much more
dangerous to the environment if dumped in the trash, which is where most of
them end up. (or worse, a recylce heap in China.)

Geoff.
 
W

William Sommerwerck

Why don't UPS manufacturers use a decent
charging circuit in their SLA-backed UPS's?

What are the differences between decent and indecent charging circuits?
 
G

Geoffrey S. Mendelson

who said:
Weight and volumetric superiority were the main attractions,
particularly for cellphones. You could fit about twenty of my Nokia
GSM phone's pack inside the NiXX pack for my old Motorola analog flip.


That's not really fair. My Motorola flip used 6 volts, and needed about 1 amp
to transmit while you were speaking. It used the AMPS system which was basicly
FM radio.

It also needed 50ma on standby.

My current cellphone (a really cheap Alcatel GSM) has a 450ma 3.6 volt battery.

In Nimh terms that would be 3 cells each 1/2 AAA size. Not much bigger or
heavier, if at all then the lithium battery in it. It would also be ok to run
it down to zero, and with the new cells last a year without discharging
(or about a week in the phone, even with it off), and go through 1,000 cycles
before dying.

As for relative size, you could put 5 or 6 of the Alcatel phones in the
1600mah pack for the flip. I actually had a lithium battery for it, it was the
size of the 600mah nicad, but held 1000mah. Cost around $100.

Geoff.
 
B

bz

That only happens with FAT and FAT32. NTFS has a journaling
filesystem:
<http://en.wikipedia.org/wiki/USN_Journal>
which does not require a fsck if the user or battery protection
circuit suddenly pulls the plug.

However, an unscheduled shutdown during an update to the directory (or
other vital) sectors does seem to be one cause of 'file xxxx.xxx not
found' BSOD computers that are brought to me to fix.
 
B

bz

I don't that very often, usually because I tend to do pre-emptive
replacements of hard disks (based on various criteria ranging from
S.M.A.R.T. reports to Ouigi board warnings). When I do see it, the
hard disk is usually ready to fail. Unfortunately, it tends to trash
files that Windoze like to scibble to constantly (i.e. the registry).

disfortunately, the grad-student owned machines only get brought to my
attention when they are infested or crashed.
(one machine had over 50,000 virus infected files! "My machine is running
slow.")
Budget and personnel restraints prevent us from doing regular PM on most
state owned machines.
However, as part of my normal 'virus clean up' (often backup data,
reformat, reinstall OS is the fastest and safest method) I do check the
hard drives for signs of impending failure.
Also, some software that claims to speed up the machine turns on HD
write-caching. Bad idea.
<http://www.pcmag.com/article2/0,2817,1819756,00.asp>
Worse are PATA and SATA drives with a large (32MB) cache on the HD.
These do cache writes and will trash anything left un-flushed in the
cache if the power fails. Moral: the bigger they are, the harder
they crash.

Same with pulling the plug on USB, eSATA, and FireWire external
drives. Lots of ways to trash data, all of which apply equally to
FAT32. Despite these and other possible problems, NTFS journaling is
a major improvement over FAT32 and should be used whenever possible.
Agreed, although one of my cow-orker swears by the latest EFTn file system.
 
B

bz

.

Well, I have a partial solution. Keep the user out of places they
shouldn't be playing.
<http://www.microsoft.com/windows/products/winfamily/sharedaccess/default
.mspx>

University policy and academic freedom....
My authority is rather limited when it comes to student owned computer or
computer under the authority of various professors. Also, many of the
computers I deal with are controling very expensive intruments.
The main problem in those cases is keeping them from putting such machines on
the internet.
It wasn't really designed for the purpose, but it's sufficient to
prevent total beginners, arrogant grad students, and ivory tower
professors, from trashing the operating system. Plenty of other
solutions, but this is the one I like. As soon as they shutdown, the
computer returns to its original state. Once a month, the PC goes
into the shop for an update, lube job, and oil change. I have it
installed at 2 car wash kiosks and one middle skool classroom. Other
than having to establish an update regime, it works well.

Would work well in a room with 50 similar computers. We don't have any
(though other departments do) such setups.
Actually, you don't really need to install MS Steady State on every
laptop in your system. Just one or two and the word will get around.
After that, merely the threat of having it installed should be
sufficient to inspire the students to clean up their act.

Also, you're being too nice. Make it clear that they are responsible
for their own data backups. If they bring a machine to you for
cleanup and disinfection, they should assume that it will be wiped and
reloaded from scratch.

When I am talking about someones years of research, I warn them to back up
everything, I ask if it is ok to wipe their drive if needed, I make an image
of the drive before I do anything to it, AND I restore all their data that
can be recovered!

I tell everyone about a guy I knew that had 9 years of research data in his
car (paper notes) and his car caught fire and burned. He never finished his
research and a few years later, he blew his brains out.

The lesson, I tell them, is
'make backups',
'make frequent backups',
'make multiple backups'
and 'keep your backups in a different place from where your computer is
located.'

It is bad enough to have to tell someone "I am sorry, I can't recover
anything from your [hard|thumb] drive.
There are companies that, for hundreds or thousands of dollars, will
disassemble it and attempt to recover your data. Is it THAT important to
you?"

I would much rather have someone say "thank you SO much for saving my data"
than "you ruined my life", or going 'postal'.
 
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