The Chemistry of Batteries in Phones and Laptops

Lithium-ion batteries power most devices because lithium is lightweight and stores lots of energy.
Anodes and cathodes are the two electrodes where charge moves in and out.
Graphite anodes host lithium ions during charging, while metal oxides act as cathodes.
Electrolytes let lithium ions shuttle between electrodes but block electrons until a circuit is made.
Charging pushes ions into the anode; discharging releases them back to the cathode, powering your device.
Cobalt, nickel, and manganese in cathodes fine-tune energy density and stability.
Battery aging happens as chemical reactions slowly degrade electrodes and electrolytes.
Heat speeds decay, which is why phones warn you when they get too hot.
Fast charging works by safely increasing ion flow, though it may shorten long-term battery life.
Solid-state batteries are the next frontier, replacing liquid electrolytes with safer, more efficient solids.