Batteries are powerhouses of smartphones. Without them, you couldn't click photos, send text messages or access dating apps. But have you ever thought about how they actually work? If you did, you've come to the right place, because this is Elemental, our latest series based on the smaller things in tech that make a much bigger impact on the real world. In this episode we explain how batteries work, be it Nickel Cadmium or Lithium-ion or even solid state batteries. We also answer morbidly curious questions like why all smartphones don't have 10,000mAh batteries and whether mili-Amp-hours or mAh are everything for smartphone batteries.