Charge balance is a crucial concept in electrochemistry, ensuring that the total positive charge in a system is equal to the total negative charge. It's essential for maintaining stability in batteries, fuel cells, and other electrochemical devices. For example, in a lithium-ion battery, the charge balance between the lithium ions moving from the anode to the cathode during discharging and vice versa during charging is vital for efficient operation and longevity. Proper charge balance helps prevent issues like overcharging, short-circuiting, and thermal runaway.