Not storage memory as much as RAM or whatever is in the iPad. I find that despite not having apps open my battery drains down, even in Airplane mode. Do you guys use any apps to help monitor this situation? It seems like there are a million different ones out there.
Without being jailbroken, there isn't much to do. If your battery is unnecessarily draining best bet is full restore and NOT restoring from backup.
There are misbehaving apps out there that seem to drain battery power even after killing them in the multi-tasking bar. The only way to get my iDevices back to normal power consumption is to hold down my power button until the turn off iDevice bar appears, then swipe to turn off. I think some apps consume power once they are installed. I recently deleted all the games off my iPhone and especially the Facebook app. Now I make it theough a typical work day with like 70% left. I used to get 0-40% with all my apps installed. The main culprit was the Facebook app, which drains my iPhone's battery unless I turn on GPS, which would also drain my iPhone battery. So deletrd.
Yeh, on my iPad 1 I tend to kill the many open apps by double-clicking the home key, then when the task bar pops up I hold down on the app icons until they appear with the small red minus sign next to them then click on the open apps I want to shut down.