Lithium-ion batteries are currently the state-of-the-art technology for energy storage for their light weight, high energy density, and compact design. For these reasons, most electric vehicles and rechargeable devices utilize lithium-ion battery technology. However, lithium-ion batteries are highly flammable and battery fires have led to the recall of cell phones, airplanes, and electric vehicles.
During charging and usage of the batteries, lithium ions are transferred back and forth between two porous electrodes. A thin porous membrane (called a separator) is used to electrically insulate the two electrodes from contacting each other. A liquid electrolyte is used to transport ions through the separator and in and out of the electrodes. However, the liquid electrolytes do not easily wick through the separators, causing increased cell resistance and assembly times. To wet the separators, thinning agents are added to the liquid electrolyte. These thinning agents are highly flammable and give rise to lithium-ion battery fires (Why Lithium-ion batteries catch fire, C&E News).
With a Hydrophilix-coated separator, electrolytes without thinning agents can be utilized, producing non-flammable lithium-ion batteries.To demonstrate this visually below, we have taken two commercial polyolefin separators and coated each one with the Hydrophilix coating. When a non-flammable electrolyte is poured over both, the difference in wetting is observed. The improvement in electrolyte uptake increases ionic conductivity and decreases the internal resistance of the cell.
If you would like Hydrophilix coated separator samples for your lithium-ion battery/electrolyte system, please reach out to us via the Contact page.