Early '08 MBP battery drop

[bwaymusgal]

I'm selling my white Macbook and currently using my FIs early '08 MBP while he is at work. Yesterday the battery power dropped very suddenly and now battery health is only 44% with 345 cycles. The other day (according to iStat Pro) the battery health was 84% with 340 cycles.

My FI is convinced that I did something to cause this and is threatening to not let me use the computer. I definitely have not done anything out of the ordinary... just web surfing, email, watching stuff on hulu, and iChat. On the apple support site a few others have seen a similar battery power drop, but most of them saw it after updating to Snow Leopard.

We are going to the Apple store a few hours away next week to get it looked at, but in the meantime I need to gather evidence that this is NOT my fault so he will stop freaking out that I am killing his computer. Has anyone else experienced this sudden drop in battery power in their early '08 MBP lately?

 

[Washuu]

The battery is getting worn out. The expected life span of a continually good battery is 300 cycles. After that the life will begin to drop and in some cases can unexpected drop rapidly. Based on your cycle usage it appears the battery has gone through around five cycles a week since it was bought. It really would not surprise me if you needed a new battery already. The reason for the sudden expected drops is usually due to the laptop finally relearning the current battery's capacity and adjusting what is displayed. The other reason being that the battery is failing.

For reference, my 2007 MacBook Pro battery only has 80 cycles, 29 months old, and has 87% of its original capacity. This is because it lives mostly on the power adapter. I could use a new power adapter though!

 

[mikes70mustang]

its wore out. my friends battery was at like 310 cycles at 100% health, and it died completely in a day. Its actually common, ive heard of batteries just dropping off suddenly, often.

 

[mrkgoo]

Sudden drops are probably a result of infrequent calibration. I find it hard to believe it wa still at 84% health after 345 cycles.