Is it normal for a battery to discharge when the computer is off?

Question

My wife has a Toshiba Satellite M500 laptop. It's running Win8 off of a fresh install from the DVD.

I've set it to hibernate fairly aggressively in an attempt to conserve standby battery life, but we still find that most times we pick it up to use it that the battery is completely discharged and it needs to be plugged in.

I did some experiments with powercfg /energy and /batteryreport to try to figure it out. I've found that while hibernated and while off, the battery drains over 30% per day. I tried physically removing the battery from the computer, and found that the battery did not discharge in that state but it's certainly not attractive to try to remember to take the battery out of a computer each time you stop using it.

Is there anything further I could do to diagnose this? The battery health indicators seem to say that the battery is healthy, but I'm wondering if replacing the battery makes sense. Or am I just spoiled by the standby life of my tablet?

Answer 1

Bought a new battery and it did not help. Because I was sure the battery was draining even while the system was off, I suspected it was some kind of firmware level problem. I poked around in the BIOS and saw the Sleep And Charge feature and disabled it. That made no difference. But once I stopped searching for satellite specific problems and started searching for Toshiba-specific battery drain problems, I had more luck.

I found this link http://cdgenp01.csd.toshiba.com/content/support/downloads/util_usb_charge_TC00130400E.exe on the toshiba forums. Even though I had shut off sleep and charge in the BIOS, nothing was fixed until I ran this utility. And the utility showed that sleep and charge was off. But once I ran it, things magically got better. I can now stay turned off for 24 hours and only lose a percent or two of power, instead of 40% or so.