[arch-general] acpi doesn't detect an external battery

[thorsopia at lavabit.com]

Hello,

acpi doesn't detect an external battery.

Using two batteries (external and internal):

Battery 0: Charging, 99%, charging at zero rate - will never fully charge

External only:

Battery 0: Unknown, 0%

Is there a way to fix this? The external one has an indicator, but it's
not enough (I'd like to know the remaining time).