TotalEnergies Lubrifiants, a division of French energy giant Total, has developed a breakthrough system of battery cooling for EVs and fitted it to a mainstream production car to demonstrate the benefits: a Renault Megane E-Tech.
The company claims the pure-electric Megane can charge twice as fast and benefits from slightly more range when fitted with its "Cell Shield" battery immersion cooling system.
Like it says in the name, immersion cooling submerges battery components in fluid to keep them cool; while EV batteries currently employ fluid cooling, they do not actually come into contact with the liquid (generally water), as that's a bad thing for electrical components.
The key to the TotalEnergies system is its Cell Shield fluid, which does not conduct electricity and can safely be used in contact with EV batteries. It does not require any major modification to the battery technology itself, and can in fact save weight and complexity because the external cooling systems currently used can be eliminated.
The company also says the Cell Shield system has safety benefits in containing thermal runaway, when batteries catch fire.
TotalEnergies Lubrifiants first applied this technology to a road vehicle in 2022, replacing the battery cooling on a Volvo XC90 plug-in hybrid with an immersion system. On the new Megane E-Tech test vehicle, the latest system has been shown to increase charge speed by a factor of two and increase range by 6%.
“We are very proud of the trust the car manufacturers have placed in us for this innovative project," says Pascal Correia, director of technology & product engineering at TotalEnergies Lubrifiants.
"Our work has demonstrated the immense potential of immersion cooling with the fluids developed by our research and development teams. The fact that we have succeeded in grafting our system onto a production vehicle demonstrates its potential on a large scale.”