Li-ion and Na-ion battery technologies have been one of the most important studies recently due to their high efficiency in energy storage field. But still, the battery life is far from satisfying the users because of intrinsic issues of materials especially on electrolyte decomposition at high voltage and capacity attenuation through cycling. This is also restricting the further developments of electric devices. Therefore more effective materials are needed. We discovered a new two-dimensional (2D) material BPt₂ with extremely high storage capacity for Li-ion and Na-ion battery applications. This robust metallic monolayer does not lose its metallic character ,which is desirable for battery applications, even under external conditions such as strain and charging. The calculated low diffusion barrier of Li and Na on BPt₂ monolayer makes it a promising candidate for next generation battery electrode material. Calculated open circuit voltages  for multilayer structures using cluster expansion formalism and density functional theory simulations indicate that upto 3 layers of Li/Na can be stored between BPt₂ layers. Therefore BPt₂ layers promise to be an effective material for  Li-ion and Na-ion battery electrode applications.