Below: a screenshot of coconutBattery taken before joining this topic.
The shot links to a folder with a text file showing my ioreg result.
On a few occasions whilst using Snow Leopard — on the first occasion, for a few days — the system advised:
Service Battery! (as pictured by TUAW in 2009)
— and I vaguely recall seeing the same, or similar, once whilst testing Lion.
When the exclamation was first given, I began following Apple's advice. Kicked myself relatively hard for never bothering to remove the MagSafe. After a few days, I can't recall how many, I arranged an on-site visit from an authorised service provider. By the time the visit was made, the specialist test revealed no problem and indeed — by that time — the system had ceased to offer the alert.
After each such incident I drift back into very bad habits (MagSafe rarely removed).
Then when I see the alert: I kick myself just lightly, begin to do the right thing (remove the MagSafe appropriately) until the caboodle reaches a point where the battery can properly allow deep sleep.
I no longer bother to seek the service suggested by the system. It seems that the computer itself performs the service — if I treat it nicely.
I recently bookmarked the following page: 15" PowerBook Battery Life Tests (George Schreyer, updated 2010) — not the most recent, but a suitably detailed starting point if ever I need to dig deeper.
