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Re: I'm losing faith in uninterruptible power supplies

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In news:d3cep7pogknnsj8cnc30adbk1o5qitr6nt@4ax.com,
Charlie Hoffpauir wrote:
> On Tue, 24 Apr 2012 16:00:20 -0500, "BillW50" <BillW50@aol.kom> wrote:
>
>> In news:tg0ep71nrp126982hfol9asom5bde898nd@4ax.com,
>> Charlie Hoffpauir wrote:
>>> On Tue, 24 Apr 2012 11:05:25 -0500, "BillW50" <BillW50@aol.kom>
>>> wrote:
>>>
>>>> I was a huge fan of uninterruptible power supplies since the
>>>> beginning (even for laptop use). Besides the computer, you can
>>>> power lots of other things. A small lamp, cordless phones, DSL
>>>> modem, alarm clock, etc. All great of course. And I have gone
>>>> through a number of UPS over the years. Generally the battery
>>>> fails after 3 to 5 years. And the batteries generally run in the
>>>> 25 to 35 buck range and they are heavy to pay for shipping. And if
>>>> you wait for a sale on UPS, you could get one for about the same
>>>> price as getting a new battery for an old one. So just get a new
>>>> one.
>>>>
>>>> Well my CyberPower 685AVR UPS battery just died recently. I tried
>>>> to disassemble it and all of the parts fit into slots between the
>>>> two halves. And trying to take it apart, some are staying in one
>>>> half and some in the other half. To get it apart, all of it has to
>>>> stay in one half. But not as easy as it seems. And I have better
>>>> things to do then to fiddle with this thing all day.
>>>>
>>>> I checked online and I thought I only paid about 50 bucks for this
>>>> one on sale. But nothing comes close to this one under 100 bucks.
>>>> Sure I could afford it, but that isn't the point. Why do I need one
>>>> again?
>>>>
>>>> Being a fan of laptops since my first one back in '84, I am also a
>>>> big fan of leaving the battery out (especially Li-Ion batteries).
>>>> As the heat and repeated charging only shortens the life of the
>>>> battery even far more than just throwing the battery in a drawer
>>>> and just using it when you really need portable power.
>>>>
>>>> This all made a lot of sense to me all of these years. Although I
>>>> now have five netbook batteries for three notebooks. Nine Gateway
>>>> batteries for nine Gateway machines. And five Alienware batteries
>>>> for five Alienware machines. That is 19 batteries of only three
>>>> different battery types. And I have plenty of them nowadays. And
>>>> only like three of them have less than 95% of their rated capacity.
>>>> Plus chemically, they will become paperweights in about 10 years
>>>> anyway no matter how well you take care of them.
>>>>
>>>> So I figure why not use some of them as an UPS instead? So what if
>>>> one wears out in two or three years? I can't possibly wear them all
>>>> out before they all will be so old to be any good anyway.
>>>
>>> Do you happen to know how to determine "which" of the terminals
>>> should be used for charging a Li-ion battery? I have a couple of
>>> good batteries that I used with my Thinkpad T42 until it died
>>> (multiple causes, finally just too much trouble to bother with). I
>>> didn't go back to another Thinkpad, and even if I did the battery
>>> probably wouldn't have been the same, so like you, I'm wondering if
>>> I can adapt them somehow as a power supply / UPS for my new Samsung
>>> notebook. BTW, there are 5 connectors on the battery, so there's
>>> probably some kind of logic built in the insure it's a real IBM
>>> battery connected before the charging will start.
>>
>> Well for starters you know that incorrect charging of Li-Ion
>> batteries are very dangerous right? And without safe guards in
>> place, they can burst into flames (flames that are almost impossible
>> to put out without a special chemical extinguisher and even then
>> maybe not). But knowing this and if you want to continue, I will.
>>
>> With a voltmeter you should find two pins that reads the battery
>> voltage (usually it is the two furthest pins, but not always).
>> Sometimes this doesn't work, but if it does you are in luck. Now you
>> have something to work with. Otherwise it can get very complicated.
>>
>> I don't know, for most people it would be better to sell them as is
>> and not mess with them. And if it has been over three years since
>> the last time they were charged, they probably are not worth
>> anything anyway. As once Li-Ion drops below 2.8v per cell I think it
>> is, it is so very dangerous to even try to change them. As they can
>> react very violently.
>
> Thanks for the information, Bill.
>
> As it turns out, I managed to find an IBM document that gives the
> Voltages to check to see if the battery is OK: Terminal 1 less than
> 11.0 vs ground (terminal 5) and the battery is bad. Mine tests at the
> max 12.6v, so the battery is OK and the charger works!
>
> So recharging isn't a problem, since the charging mechanism is OK...
> now I just need to find out if the Samsung will work OK on 11-12.6 on
> the input. Then I'd just use the IBM battery as an external power
> supply (providing I can cludge up proper connectors).

Everything sounds great to me so far.

> BTW, I didn't mention, but the Samsung is one of those Series 7 models
> with a "non-removable" internal battery. After reading the
> documentation over more carefully, it looks like the Samsung will
> charge to 80 %, then run off the battery until charge drops to (not
> sure, but think 40%), then charge to 80 % again if connected to the
> charger. Apparently it runs off the external supply without recharging
> the battery between the 80% and about 40% levels.... of course, the
> battery isn't discharging, so it basically runs off external power
> only.

Oh beautiful! Most laptop manufactures try to squeeze all of the
capacity they can out of a battery for bragging rights. Yes that works
but the batteries don't last long. This is 4.2v per cell (careful some
battery packs might be in partly parallel, so you can't really count the
cells if known for the total voltage). I have found that up to 4.1v per
cell without heat will provide 5 years of service easy (unless you
recharge past hundreds of times during its life). 4.2v per cell they
generally don't last more than 2 or 3 years.

Almost all documents you read about this says Li-Ion batteries last the
longest at 40% of charge (aka capacity). I don't disagree with this at
all and that sounds right by me. But that would be impossible unless you
had a special charger to do so (you could build one of course). But if
one kept the charge between 40 to 80% I believe would do almost just as
good. So kudos to Samsung for at least trying to get it right.

> The Samsung external power supply/charger doesn't state what the
> output voltage is, but under no load, measures 19v DC. The IBM
> external brick measures only 16.5 no load.... so I'm not sure that the
> 12.6 output by the IBM battery would be enough to charge the Samsung.

Oh that doesn't sound like that will work being stock. You will most
likely need a DC to DC converter.

-- 
Bill
Gateway M465e ('06 era) - OE-QuoteFix v1.19.2
Centrino Core Duo T2400 1.83GHz - 2GB - Windows XP SP3

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Thread

I'm losing faith in uninterruptible power supplies "BillW50" <BillW50@aol.kom> - 2012-04-24 11:05 -0500
  Re: I'm losing faith in uninterruptible power supplies Charlie Hoffpauir <invalid@invalid.com> - 2012-04-24 15:19 -0500
    Re: I'm losing faith in uninterruptible power supplies "BillW50" <BillW50@aol.kom> - 2012-04-24 16:00 -0500
      Re: I'm losing faith in uninterruptible power supplies "BillW50" <BillW50@aol.kom> - 2012-04-24 17:04 -0500
      Re: I'm losing faith in uninterruptible power supplies Charlie Hoffpauir <invalid@invalid.com> - 2012-04-24 18:19 -0500
        Re: I'm losing faith in uninterruptible power supplies "BillW50" <BillW50@aol.kom> - 2012-04-25 18:48 -0500
          Re: I'm losing faith in uninterruptible power supplies Bob_Villa <pheeh.zero@gmail.com> - 2012-04-25 19:15 -0700
            Re: I'm losing faith in uninterruptible power supplies "BillW50" <BillW50@aol.kom> - 2012-04-26 11:45 -0500
              Re: I'm losing faith in uninterruptible power supplies "RnR" <rnrtexas@gmail.com> - 2012-04-28 01:57 -0500
                Re: I'm losing faith in uninterruptible power supplies "BillW50" <BillW50@aol.kom> - 2012-04-28 12:19 -0500
            Re: I'm losing faith in uninterruptible power supplies "RnR" <rnrtexas@gmail.com> - 2012-04-28 01:47 -0500
  Re: I'm losing faith in uninterruptible power supplies philo <philo@privacy.net> - 2012-04-24 15:45 -0500
    Re: I'm losing faith in uninterruptible power supplies "BillW50" <BillW50@aol.kom> - 2012-04-24 16:23 -0500
      Re: I'm losing faith in uninterruptible power supplies "SC Tom" <sc@tom.net> - 2012-04-24 19:51 -0400
        Re: I'm losing faith in uninterruptible power supplies "BillW50" <BillW50@aol.kom> - 2012-04-26 11:39 -0500
  Re: I'm losing faith in uninterruptible power supplies "RJK" <nosuch@hotmail.com> - 2012-05-16 23:02 +0100
    Re: I'm losing faith in uninterruptible power supplies Ant <ant@zimage.comANT> - 2012-05-16 20:03 -0700
    Re: I'm losing faith in uninterruptible power supplies Roland Mösl <founder@pge.org> - 2012-05-17 08:34 +0200

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