[ltp] T4x Battery Conditons Survey

[Eric Van Buggenhaut]

On Sat, Dec 17, 2005 at 10:09:42PM +0100, Michael Gaber wrote:
> Eric Van Buggenhaut wrote:
> >On Sat, Dec 17, 2005 at 01:58:55PM +0000, Peter B. West wrote:
> >>Eric Van Buggenhaut wrote:
> >>>On Fri, Dec 16, 2005 at 03:53:03PM +0800, Kelvin KAN wrote:
> >>>
> >>>>Now nearly 1 yr, in 38 charging cycles, the battery capacity of my 
> >>>>T42 has dropped from 4700mAh (designed) to 4200mAh (fully charged).   
> >>>>Projecting this degradation into next yr, it will be practically 
> >>>>giving me only 2-hr running by next X'mas.
> >>>>
> >>>>To be honest, I've been using the battery with great care and have 
> >>>>removed the battery while running on AC.  And 38 charge cycles in 1 
> >>>>yr does NOT seem too frequent.
> >>>>
> >>>>How's yours?  Really an IBM (not Lenovo) quality issue?
> >>>
> >>>Same problem here. When I bought my T42 they claimed the battery to 
> >>>stand 5h. I never went beyond 3h (which is normal: 47000mAh/16000mW = 
> >>>~3).
> >>>
> >>>After one year of intensive use (200 charges) always emptying the 
> >>>battery before charging, I get a max. capacity of 42000mAh just like 
> >>>you. I'm kind of disappointed by this aspect of the Thinkpads, 
> >>>probably the only weak point of this laptop.
> >>This sounds like great battery performance to me.  If this is typical 
> >>of ThinkPad batteries, we have nothing to complain about.  Try a Dell 
> >>sometime.
> >
> >Well, after loading smapi, I can give much more precise data:
> >
> >atto:~[0]# cat /sys/devices/platform/smapi/BAT0/design_capacity
> >47520 mWh
> >atto:~[0]# cat /sys/devices/platform/smapi/BAT0/cycle_count
> >266
> >atto:~[0]# cat /sys/devices/platform/smapi/BAT0/remaining_capacity
> >29970 mWh
> >
> >After a complete charge. So I lost 30% in one year, much more than 
> >what I thought first
> >
> 
> try cat'ing last_full_capacity, thats the better point to look than the 
> remaining capacity

Not really better:

# cat /sys/devices/platform/smapi/BAT0/last_full_capacity 
30680 mWh



-- 
Eric VAN BUGGENHAUT
Eric.VanBuggenhaut@AdValvas.be