Anode
Anode is the electrode where oxidation occurs. In a lithium-ion battery delivering power, it is the negative electrode: electrons leave it through the external circuit, while lithium ions move through the electrolyte toward the positive electrode.
In a rechargeable battery
Charging reverses the cell reactions. Strictly, the electrode acting as the anode therefore changes with the direction of the reaction. Battery engineering commonly keeps anode as the name for the negative-electrode material and assembly defined during discharge, avoiding a name change whenever the current reverses. Negative electrode is the less ambiguous term.
Graphite is a well-established anode active material in commercial lithium-ion batteries. The term may refer narrowly to that active material or more broadly to the practical negative-electrode assembly.
Why it matters
Anode chemistry and construction influence how much charge a cell can store and how quickly it can accept charge. They also affect formation of the solid electrolyte interphase (SEI), degradation and the risk of lithium plating. These outcomes depend on the complete cell design and operating conditions, not the anode alone.
For electrode materials, interfaces and complete-cell trade-offs, see Cell Chemistry & Components.