Like the other brand tablets that the Alldocube Tablet are equipped with the battery from the Alldocube Power M3 built in a 8000mAh battery to the Alldocube X1 equipped with 4500mAh battery that different model use different capacity battery. Do not worry, there is not the situation like the PIPO X8 pro that do not built in the battery that all the cube tablets come with a built in battery. You can look at here: http://www.cube-tablet.com/buy-products.html