A New Energy Storage Mechanism of Liquid Lithium-Ion Batteries

The academic and industrial communities generally describe the energy storage mechanism of lithium ion batteries as chemical energy storage. It is believed that charging and discharging rely on the breaking and reformation of chemical bonds as well as redox chemical reactions to store and release energy. This traditional theory only summarizes macroscopic phenomena. It cannot explain a series of key microscopic characteristics of lithium-ion batteries, including overall electrical neutrality, spatial separation of positive and negative charges without neutralization, electricenergy shunting during simultaneous charging and discharging, stable energy retention after power off without spontaneous energy release, and slow ordered energy discharge when connected to a load. Based on the light origin theory, this paper establishes a novel physical energy storage mechanism for lithium-ion batteries. A lithium-ion battery involves no chemical reactions, no formation of new substances and no reconstruction of chemical bonds, so it is not a chemical energy storage device. Its intrinsic energy storage essence lies in the reversible storage and release of graphite lattice perturbation potential energy generated by the spatial separation of positive and negative charges. During charging, lithium ions detach from the lattice gaps of the positive electrode and migrate through the electrolyte and separator to the interlayers of the graphite negative electrode. The negative electrons left behind after lithium-ion detachment are permanently trapped within the lattice skeleton of the positive electrode and do not migrate. The spatial separation of positive and negative charges builds lattice confinement potential energy. The stored energy remains stable during charging and after power off because a conductive discharge circuit is absent and lithium ions cannot migrate back. When a load is connected to form a closed discharge circuit, the resistance of the load limits the discharge rate. Energy cannot be released instantaneously. The returning speed of lithium ions adapts to the power consumption of the load and releases lattice perturbation potential energy in an orderly way. Upon discharge, the spatial separation of charges disappears, the lattice rebounds and resets, and the stored lattice perturbation potential energy is directly converted into electric energy packets for external work. This paper clearly distinguishes chemical energy storage of traditional zinc manganese disposable dry cells from physical potential energy storage of lithiumion batteries, and explains the electric energy shunting phenomenon when a mobile phone is used while charging. It points out that future battery research should focus on charge spatial separation effect, lattice electron locking stability and controllable lattice perturbation. The long standing theoretical misunderstanding in electrochemistry is corrected.