I normally fall asleep with my Macbook on, however after some time it sleeps automatically. When coming to use it the following day it wakes up as normal, battery is not drained. It functions for a few seconds, then freezes momentarily and shuts down. If I clip on the charging cable and leave it for a few seconds it will wake up again however there is no orange tick next to the password bar as would appear if the Macbook had shut down due to a drained battery. When entering the desktop the battery appears to be at the same percentage as before. Battery diagnostic from Macbook System Information below:
Charge Information:
Charge Remaining (mAh): 1296
Fully Charged: No
Charging: Yes
Full Charge Capacity (mAh): 6374
Health Information:
Cycle Count: 356
Condition: Normal
Charge Information:
Charge Remaining (mAh): 1296
Fully Charged: No
Charging: Yes
Full Charge Capacity (mAh): 6374
Health Information:
Cycle Count: 356
Condition: Normal