Chosen Solution
I’ve just bought an A1278 off eBay that has 3682 charge cycles on the battery, which is roughly double the maximum I’ve ever seen on one of these.
I know Apple says that they’re good for 1000 cycles, but wondered if anyone else had seen such an outlier?
Time for a new battery for sure! MacBook Unibody (A1278) Battery It probability dies in less than 30 mins when you disconnect the charger.