Energy density refers to the amount of energy a battery can store per unit volume. Nanomaterials increase energy density by enabling more efficient and densely packed electrode structures. For instance, silicon can store more lithium ions compared to traditional graphite, but it tends to expand and contract, leading to degradation. However, using silicon in the form of nanowires or nanoparticles mitigates these issues, resulting in higher energy densities without compromising stability.
