Electrolyte Analysis

Liquid electrolyte plays a key role in commercial lithium-ion batteries to allow conduction of the lithium-ions between cathode and anode. The most commonly used electrolyte is comprised of lithium salt, such as LiPF6 in an organic solution.

High purity is required to prevent oxidation at the electrode and to promote good cycle life. In addition to lithium salt, various additives are also included in the final electrolyte solution. These additives are mixed with the LiPF6 solution to prevent lithium dendritic formation and degradation of the solution.

There are electro kinetic phenomena caused by charge separation at the separator-electrolyte interface. Diffusion of charged electrolyte solution through the pores of the separator has to undergo the influence of the zeta potential at the interface.

The zeta potential at that interface may impede or aid the passage of the electrolyte across the separator. The zeta value gives an indication of the potential stability of a system: the larger the value (positive or negative) the more stability of the solution.