I can't help I'm afraid but thought I would say that I have been trying to work this out too. The same thing happens on the EM10 and it would be handy to be able to check the battery status without turning the cameras off and on again to find out. Hope someone out there can help us. I have checked the manual and it isn't much help!
I hadn't thought of it that way. I use a Panasonic bridge camera in addition to M43 and the symbol is always displayed on the Panny screen which I find reassuring. I will now think of no battery symbol being reassuring instead!