What does a yellow triangle with a question mark mean on an Lg G3?

[Android Central Question]

I got a new Lg G3 phone and opened the box and installed the battery. I do not have a SIM card installed yet. I plugged the charger in and pressed the power button and on the screen I see a battery with a yellow triangle with a question mark. What does this mean? I have used a total of three different chargers and I get the same thing every time. Also, the phone will not power on at all. Help please!!