In lithium-ion batteries, the anode is also negative when discharging. The primary material used for this electrode is graphite. Lithium ions move from cathode to anode during charging and intercalate into graphite layers. The reaction at the anode can be represented as: Li⁺ + e⁻ + C → LiC₆
Lithium (Li) metal is widely recognized as a highly promising negative electrode material for next-generation high-energy-density rechargeable batteries due to its exceptional specific capacity (3860 mAh g −1), low electrochemical potential (−3.04 V vs. standard hydrogen electrode), and low density (0.534 g cm −3).
In lead-acid batteries, the anode is negative during discharge. The sponge lead (Pb) acts as this electrode, while lead dioxide (PbO2) is the cathode. The oxidation reaction at the anode can be expressed as: Pb + SO₄²⁻ → PbSO₄ + 2e⁻ This indicates that lead loses electrons (is oxidized), confirming its role as a negative electrode.
Lithium-Ion Batteries: Graphite is typically used as the anode in lithium-ion batteries. When discharging, it acts as a negative electrode. Lead-Acid Batteries: Lead dioxide (PbO2) is the positive terminal during discharge, while sponge lead (Pb) is the negative terminal.
Lithium-ion batteries employ lithium compounds as the active material for both the positive and negative electrodes. These batteries consist of a positive electrode (cathode) made of lithium cobalt oxide, a negative electrode (anode) typically composed of graphite and a separator that prevents direct contact between the electrodes.
Although these processes are reversed during cell charge in secondary batteries, the positive electrode in these systems is still commonly, if somewhat inaccurately, referred to as the cathode, and the negative as the anode. Cathode active material in Lithium Ion battery are most likely metal oxides. Some of the common CAM are given below