Why use synthetic esters instead of mineral oil?

In terms of direct liquid immersion cooling, esters have advantages compared to other chemistries used in immersion cooling for several reasons:

MIVOLT esters are single-phase liquids and have a higher boiling point compared to pure hydrocarbons for a given viscosity.  This characteristic lowers the risk of evolving vapour in operation or losing liquid through evaporation.

Esters are more thermally stable than pure hydrocarbons for a given viscosity and are less likely to break down or decompose when exposed to high temperatures. This stability helps to maintain the integrity of the fluid and reduces the risk of contamination, which can cause equipment failure.

Esters are less flammable than pure hydrocarbons for a given viscosity, reducing the risk of fire in critical electrical and electronic components. This is particularly important in environments like data centres, where there is a high concentration of electrical equipment, as a fire in this environment could result in significant damage to equipment and data as well as pose a serious threat to human life.

Unlike mineral oil and fluorinated liquids, esters are readily biodegradable, making their selection a more environmentally friendly choice.

This is important across the spectrum of applications; in data centres, the use of large quantities of fluid can have an impact on the environment; in electric vehicles, the potential for leaks arising from crashes means reduced environmental harm.

In terms of performance, esters have a higher thermal conductivity than mineral oils, meaning they are more effective at transferring heat from equipment to the cooling system.

This improved thermal conductivity results in more efficient cooling and helps to prevent equipment from overheating.

The use of esters for immersion cooling offers several advantages, including higher boiling point, enhanced thermal stability, reduced flammability and biodegradability, all at a lower viscosity than pure hydrocarbon-based liquids.

These advantages make esters the superior choice for use in battery systems and data centres, where efficient cooling and equipment protection are critical.