Odd ACPI/Battery Behavior

["Leo L. Schwab" <ewhac@best.com>]

	I have a Sony Vaio VGN-S150 laptop that has been displaying odd
behavior in reporting available battery power.  While left charging, the
system sometimes reports low or no energy remaining in the battery until
it's fully charged, then reports 100%.

	Today I had occasion to run the battery to zero.  I then plugged in
the AC adapter and freshly cold-booted the machine.  The ACPI meter
persistently reported zero percent power available for well over an hour
before it finally jumped to 100%, after the battery was fully charged.  

	It seems to indulge in this strange behavior when the battery is
drained to about 30% or lower.  Here's a copy of an 'acpitool' report while
it was "empty" but charging:

----
ewhac@walkies:~$ acpitool -e
  Kernel version : 2.6.17   -    ACPI version : 20060127
  -----------------------------------------------------------
  Battery #1     : present
    Remaining capacity : 0 mWh, 0.00%, 05:34:55
    Design capacity    : 53280 mWh
    Last full capacity : 41580 mWh, 78.0% of design capacity
    Capacity loss      : 22.0%
    Present rate       : 7449 mW
    Charging state     : charging
    Battery type       : non-recharge, LION

  AC adapter     : on-line
  Fan            : <not available>

  CPU type               : Intel(R) Pentium(R) M processor 1.60GHz
  CPU speed              : 600.000 MHz
  Cache size             : 2048 KB
  Bogomips               : 1198.35
  Processor ID           : 0
  Bus mastering control  : yes
  Power management       : yes
  Throttling control     : yes
  Limit interface        : yes
  Active C-state         : C2
  C-states (incl. C0)    : 3
  Usage of state C1      : 10 (0.0 %)
  Usage of state C2      : 3216278 (100.0 %)
  T-state count          : 8
  Active T-state         : T0

  Thermal zone 1 : ok, 42 C
  Trip points : 
  ------------- 
  critical (S5):           100 C
  passive:                 90 C: tc1=1 tc2=2 tsp=50 devices=0xc1479620 


   Device	Sleep state	Status
  ---------------------------------------
  1. PWRB	   4		* enabled
  2. PCIB	   3		disabled
  3. LANC	   3		disabled
  4.  EC0	   5		disabled
  5. USB0	   3		disabled
  6. USB1	   3		disabled
  7. USB2	   3		disabled
  8. USB7	   3		disabled
  9. MODM	   3		disabled
----

	I'd replace the battery, but the prices for Sony-branded batteries
are particularly usurious (and, with even OEM batteries exploding left and
right, I'm not at all interested in going aftermarket).

	Has anyone seen anything like this before?

					Schwab