How does a lithium-ion battery work?
ll batteries work by having two electrodes—an anode and a cathode—with a bunch of a material called electrolyte between. When you plug a battery into a completed circuit, a chemical reaction starts taking place at the anode and electrons start building up over there. Those electrons want to travel to the cathode, where it's less crowded, but the electrolyte between these two parts keeps the electrons from taking the short way there. The only way through is the circuit that the battery is crammed into, and those electrons power your device in the process. Meanwhile, the positively charged lithium ions the electrons leave behind travel through the electrolyte to meet the electrons on the cathode side. Once all the electrons have made the trip, your battery is dead. Except! If you're using a rechargeable battery like a lithium-ion, you can reverse the process. If you dump energy into a circuit using a charger, you can force the reaction to go in the other direction and get that ...