Even on the older rMBP (mine is 2012) my system just goes on suspend mode at 15-20% battery, even when I'm not doing much so the estimates shouldnt have been th

Even on the older rMBP (mine is 2012) my system just goes on suspend mode at 15-20% battery, even when I'm not doing much so the estimates shouldnt have been that far off. Did all the SMC reset steps and same issue.