Battery recalibrate ideas

"BillW50" <> wrote in message
news:hcptll$f7j$...
> In news:4aefeba0$,
> M.I.5¾ typed on Tue, 3 Nov 2009 08:37:22 -0000:
>> "BillW50" <> wrote in message
>> news:hcngj2$i5f$...
>>> Maybe this URL may help. It seems accurate as far as I can tell.
>>>
>>> http://www.mpoweruk.com/lithium_failures.htm
>>>
>>> Which says that lithium batteries will last longer if they are
>>> operated between 15°C (59°F) to 50°C (122°F). And by 70ºC (158°F)
>>> the threat is really from thermal runaway. Poof!
>>
>> 50°C???!!!?? That will kill a Lithiom ion in no time at all.
>
> It seems too high to me too. But I don't have any hard evidence that they
> are incorrect. I am currently testing one battery sitting at 95°F (35°C)
> and floated at 4.2v per cell. IMHO 4.2v is too high (but 4.10v is fine),
> but you say it is okay. And I am not sure about 95°F, but I am hoping this
> isn't warm enough to do any real harm.
>

Laptops don't heat batteries by anywhere near this much and they kill them
inside a year.

In news:4af1594c$,
M.I.5¾ typed on Wed, 4 Nov 2009 10:37:37 -0000:
> "BillW50" <> wrote in message
> news:hcptll$f7j$...
>> In news:4aefeba0$,
>> M.I.5¾ typed on Tue, 3 Nov 2009 08:37:22 -0000:
>>> "BillW50" <> wrote in message
>>> news:hcngj2$i5f$...
>>>> Maybe this URL may help. It seems accurate as far as I can tell.
>>>>
>>>> http://www.mpoweruk.com/lithium_failures.htm
>>>>
>>>> Which says that lithium batteries will last longer if they are
>>>> operated between 15°C (59°F) to 50°C (122°F). And by 70ºC (158°F)
>>>> the threat is really from thermal runaway. Poof!
>>>
>>> 50°C???!!!?? That will kill a Lithiom ion in no time at all.
>>
>> It seems too high to me too. But I don't have any hard evidence that
>> they are incorrect. I am currently testing one battery sitting at
>> 95°F (35°C) and floated at 4.2v per cell. IMHO 4.2v is too high (but
>> 4.10v is fine), but you say it is okay. And I am not sure about
>> 95°F, but I am hoping this isn't warm enough to do any real harm.
>
> Laptops don't heat batteries by anywhere near this much and they kill
> them inside a year.

Are you sure? As plastic feels so much cooler than say metal. My Asus
EeePC netbooks gets 110°F top and bottom. Although the battery is much
cooler. AJL calls his hot, while I call this lukewarm. And this is much
cooler than my laptops. My Toshiba 2595XDVD ('99 era) laptops for
example, are really hot. I should check them with my IR temperature gun.
They have to be in 130°F range on the bottom at least. And the batteries
has to be very close to this.

--
Bill
Asus EEE PC 701G4 ~ 2GB RAM ~ 16GB-SDHC
Windows XP SP2

In news:,
AJL typed on Wed, 04 Nov 2009 15:34:22 -0700:
> "BillW50" <> wrote:
>
>> My Asus EeePC netbooks gets 110°F top and bottom. Although the
>> battery is much cooler. AJL calls his hot, while I call this
>> lukewarm.
>
> I didn't call your Eee PC netbook hot, I called my Eee PC netbook hot,
> specifically my 2G Surf model (7" screen, 520M memory, 2G SSD). To the
> touch it runs very hot. Course at only 2 pounds I usually hold it like
> a newspaper to read it so perhaps it gets touched more. It has never
> had a problem during operation so I'm guessing that it is just the
> nature of the beast. While your netbooks look like this model there
> are several differences and heat is apparently one of them.
>
> Contrary to what you would think my more powerful netbook the Eee PC
> 1000HD (10" screen, 1G memory, 160G HDD) runs much cooler than the
> little Surf and gets almost twice the battery time (same capacity
> battery). So in later designs (and more expensive models) the design
> has improved...

It is ashamed you don't have anything to measure the temperature with.
As I really believe we have different opinions on what we call hot. Most
of the keyboard and the bottom of mine runs about 102°F. Although by the
right ALT key gets 110°F and one spot on the bottom also gets 110°F
(where the WiFi card sits). It is 75°F in this room and if left in
standby, runs about 85°F top and bottom. While the battery capacity
rating between your two, the 1000HD has a higher rated battery voltage,
right?

--
Bill
Asus EEE PC 701G4 ~ 2GB RAM ~ 16GB-SDHC
Windows XP SP2 (quit Windows updates back in May 2009)

In news:,
AJL typed on Wed, 04 Nov 2009 16:26:06 -0700:
> "BillW50" <> wrote:
>
>> My Asus EeePC netbooks gets 110°F top and bottom.
>
> I just noticed this *Cool* article...
>
> http://www.reghardware.co.uk/2009/11...us_thermal_pc/

Oh I like that! ;-)

--
Bill
Asus EEE PC 701G4 ~ 2GB RAM ~ 16GB-SDHC
Windows XP SP2 (quit Windows updates back in May 2009)

Re: "I wish I had a way to accurately measure the surface temperature"

What would you do if you thought you had the flu? My guess is that you
do have a temperature measuring device.


AJL wrote:
> "BillW50" <> wrote:
>
>> It is ashamed you don't have anything to measure the temperature with.
>
> Yes, I wish I had a way to accurately measure the surface temperature
> so we could compare. I probably need one of those surface
> thermometers. Maybe I could sneak the Surf into Home Depot and use the
> demo??
>
>> As I really believe we have different opinions on what we call hot.
>
> That could very well be. Here in Phoenix we often are over 110 degrees
> in the summer and yes I do call that hot...
>
>> While the battery capacity rating between your two, the 1000HD
>> has a higher rated battery voltage, right?
>
> Both batteries are 7.4V (4400 mAh). In fact their outside dimensions,
> including the curves, are identical. Course Asus put a different
> connector in each so I can't interchange them...

AJL wrote on Wed, 04 Nov 2009 16:52:53 -0700:
> "BillW50" <> wrote:
>
>> It is ashamed you don't have anything to measure the temperature with.
>
> Yes, I wish I had a way to accurately measure the surface temperature
> so we could compare. I probably need one of those surface
> thermometers. Maybe I could sneak the Surf into Home Depot and use the
> demo??
>
>> As I really believe we have different opinions on what we call hot.
>
> That could very well be. Here in Phoenix we often are over 110 degrees
> in the summer and yes I do call that hot...
>
>> While the battery capacity rating between your two, the 1000HD
>> has a higher rated battery voltage, right?
>
> Both batteries are 7.4V (4400 mAh). In fact their outside dimensions,
> including the curves, are identical. Course Asus put a different
> connector in each so I can't interchange them...

I have been checking the temperatures of both Asus and my Toshiba
2595XDVD laptops. Those Toshiba laptops I always thought of being hot.
Although they only read 110F at a few spots. Only when the fan kicks on
high, I can read 130F coming out of the fan. The Asus netbooks, the
highest I read is 110F. And not much difference if I am running Linux or
Windows XP. So maybe the Asus 700/701/702 *does* run hot. ;-)

--
Bill
Asus EEE PC 702G4 ~ 2GB RAM ~ 16GB-SDHC
Xandros Linux (build 2007-10-19 13:03)

After 48 hours of freezing, there seems to be no real change in the
battery meter functioning.
I think there has been a slight increase in the elapsed time before
the Critical level indicator comes up. But, I could be thinking it up.
In any case, the battery lasts for another 4 mins more after this.
So...