A battery's ability to store and provide energy faces the fundamental limitation that its energy source is chemical in nature. Conventional battery designs are essentially a pair of plates made of different metals separated by an electrolyte that allows movement of electrons and ions between them.
Micro Battery is Power capacity is roughly determined by the internal resistance of the battery, so plates with larger surface area can deliver more power. Energy capacity is related to the physical size of the battery and the energy of the chemical reactions powering it.