Apabila evolusi elektronik mudah alih berkembang, berat peranti terus berkurangan. Dalam banyak kes, bateri atau pek bateri merupakan komponen paling penting bagi peranti elektronik mudah alih.
Generally, carbon-based batteries offer lower weight compared to alkaline batteries but sacrifice performance.
Lithium battery cells, on the other hand, are lighter than alternative primary chemistries. For instance, while a AAA alkaline battery typically weighs around 12 grams, a AAA lithium battery weighs only 8 grams. Moreover, lithium cells typically boast superior shelf life and performance.
Li-ion and lithium polymer batteries significantly outweigh other rechargeable batteries of similar size, contributing to the enhanced portability of numerous electronic devices.