[ltp] Thinkpad T23 Battery

[Martin Steigerwald]

Am Samstag, 22. Januar 2005 07:26 schrieb Harry Popov:

> > When the battery is installed and the laptop is used on AC power,
> > the battery is normally charged to full capacity. This contains
> > two dangers for the battery:
> >
> > 1. Heat
> > 2. 100% charge state
>
> None of these is true. First the batery is not under charge all the
> time. The charging unit is swithing it off the mains at 100%
> charging. Second the best condition for the batery if not in use is
> to be charged 100% and kept at 7C temperature. It can stay save for
> years there.

Hello Harry,

its astonishing how many different oppinions are available on this topic.

I read an article in c't magazin (http://www.heise.de) where the author 
claims the following:

1) leaving a battery in the laptop that is connected via AC connerctor 
causes it to get worse early since the laptop often recharges the battery 
back to 100%. The author explains that each recharge cycle, even when it 
only recharges a few percent of capacity, counts as a full recharge 
cycle. He also states that a notebook battery can do about 1000 recharge 
cycles.

2) It is not good to store a battery which is not in use charged at 100%. 
Better would be using 80% and not below 50%. Thus when you store a 
battery for years you would better check that it doesn't go below 50% 
charge. He also says it doesn't help putting a battery into the 
refrigerator, but it should be kept below usual room temperature when 
storing it for a longer time. I do not know his exact explains, but it 
goes along the way that high charge and high temperate are not good for 
battery health.

> Second good way to keep the long life of not used batery is to be
> charged at 100% and stay under tiny charging condition. It can be
> kept for age in this way. Exactly what is happening if the notebook
> is on the mains. This condition is not true only if the charging
> unit of the computer is broken.

On the mains? What does that mean? My english leaves me here. Does it mean 
to be connected with AC connector? That would be exactly the condition 
the author of that c't article doesn't recommend.

Regards,
-- 
Martin 'Helios' Steigerwald - http://www.Lichtvoll.de