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Re: Dead battery after storage on T400s

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bp@www.zefox.net wrote:
> Computer Nerd Kev <not@telling.you.invalid> wrote:
>> bp@www.zefox.net wrote:
>>> Computer Nerd Kev <not@telling.you.invalid> wrote:
>>>> bp@www.zefox.net wrote:
>>> 
>>> I wondered about re-celling the old battery pack, but couldn't
>>> find any descriptions of folks actually doing it and one demo
>>> of letting the magic smoke out, so I'm wary.
>> 
>> Seems like there are videos on YouTube, though I made it up as I
>> went along since it's just a case of hooking things up like they
>> were when you started (after fighting your way in). I've read some
>> battery controllers might 'die' when you disconnect the old cells
>> if you don't hook external power to them, so they're tricky.
>> 
>>> It's also unclear what kind of cells are required. 
>> 
>> The type of Li-Ion cell is almost always 18650. The capacity (mAh)
>> is the only thing that varies, and can be calculated by comparing
>> the battery circuit (add up the capacity of the batteries in
>> parallel) with the capacity of the battery pack if it's not printed
>> on the cells themselves (often it is). Note that over-stated
>> capacity figures are a common complaint with cheap Chinese
>> replacement cells. You can also choose to use different capacity
>> cells, but the OS's battery hours estimate might be wrong then.
>> 
> 
> I can't see how the cells could be 18650, the pack is only about
> half an inch thick. Even AA cells are too thick to fit.

OK, might be the flat cells like they use in phones.

> Maybe that's why replacement packs seem scarce.

Seems like Lenovo might still be making them actually. Quite a few
sellers claiming to have genuine "Thinkpad battery 59+" in stock,
if that's the right one.

>>> In the meantime I set the power button to shut down while on both
>>> battery and mains. Turned the machine off, it seemed to do so.
>>> Couple hours later I noticed the machine was warm, opened the lid,
>>> found it was up and running. Re-checked "what the power buttons do"
>>> and they still claimed to cause shut down. This looks like a bug.
>>> Anybody else seen this behavior? 
>> 
>> Sometimes I've had thinkpads intermittently fail to fully turn off
>> at shut-down, just sit running with a black screen and maybe the
>> CPU fan running. Holding the power button down for a while forces
>> them off. It doesn't boot back up though, just hangs, so it must be
>> a bug.
>> 
>> You could check that Wake on LAN is disabled in the BIOS settings.
>>
> 
> I looked for wake on LAN, but couldn't find it in the BIOS. Might it
> be set in Windows 10?

I doubt it, usually it's set in the BIOS. I've seen the option on
earlier Thinkpads, believe it or not the T400s is still a bit too
new for me.

> Haven't seen it there, but I'm mostly unfamiliar
> with Win10 and could easily miss it. I'm certain I didn't hit the power
> button, but did unplug and plug the power jack and also open/close the
> lid. Could either trigger a startup?

I wouldn't have thought so, unless the OS didn't really shut down
fully after all.

> The machine stayed off all night, when I checked the battery this morning
> it read 12.26 volts, same as last night. No parasite drain. Knowing now
> where to test voltage direct on the battery I'm tempted to apply a small
> light bulb load, say 2 amps, to do a capacity check independent of the
> computer.

Not recommended. Over-discharge could kill it, or even cause it to
catch fire when you try to charge it again (although the battery
controller should prevent that).

> Any hint what the several intermediate contact on the battery do?

They're so the battery controller can talk to the PC and tell it
things like why it doesn't want to charge because someone hooked
a light bulb to it and over-discharged it.

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Dead battery after storage on T400s bp@www.zefox.net - 2025-01-14 01:50 +0000
  Re: Dead battery after storage on T400s bp@www.zefox.net - 2025-01-14 18:11 +0000
    Re: Dead battery after storage on T400s not@telling.you.invalid (Computer Nerd Kev) - 2025-01-15 06:40 +1000
      Re: Dead battery after storage on T400s bp@www.zefox.net - 2025-01-15 17:25 +0000
        Re: Dead battery after storage on T400s Adrian Caspersz <email@here.invalid> - 2025-01-15 21:02 +0000
          Re: Dead battery after storage on T400s bp@www.zefox.net - 2025-01-15 22:03 +0000
        Re: Dead battery after storage on T400s not@telling.you.invalid (Computer Nerd Kev) - 2025-01-16 07:44 +1000
          Re: Dead battery after storage on T400s bp@www.zefox.net - 2025-01-15 22:45 +0000
            Re: Dead battery after storage on T400s Computer Nerd Kev <not@telling.you.invalid> - 2025-01-16 13:47 +1000
              Re: Dead battery after storage on T400s bp@www.zefox.net - 2025-01-16 16:10 +0000
                Re: Dead battery after storage on T400s Computer Nerd Kev <not@telling.you.invalid> - 2025-01-17 12:53 +1000
                Re: Dead battery after storage on T400s bp@www.zefox.net - 2025-01-17 04:26 +0000
                Re: Dead battery after storage on T400s bp@www.zefox.net - 2025-02-07 19:05 +0000
                Re: Dead battery after storage on T400s not@telling.you.invalid (Computer Nerd Kev) - 2025-02-08 07:49 +1000
                Re: Dead battery after storage on T400s bp@www.zefox.net - 2025-02-08 20:33 +0000
                Re: Dead battery after storage on T400s not@telling.you.invalid (Computer Nerd Kev) - 2025-02-09 09:54 +1000
                Re: Dead battery after storage on T400s bp@www.zefox.net - 2025-02-09 01:44 +0000

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