Hi, I have a 1st gen MBA. The battery was replaced earlier this year and it still has 96% health. But starting today, my computer frequently shows no batteries available and then goes back to normal after about 15 to 20 minutes. When the battery cannot be detected, the enclosure bottom temp shown in iStat is -127, which goes back to ~30 when battery is being detected. Also, it loses about 5% battery per hour in sleep mode. When it is awake, battery life is about 5-6 hours which is pretty normal. I have done battery calibration, SMC reset, PRAM. All software is up to date. Any ideas? Thanks in advance!