Free Quote
Single-phase Immersed Dielectric Coolants

OSi SiFOCool

Chemical Name:  Single-phase Immersed Dielectric Coolant

Single-phase immersion cooling is a type of submerged server cooling. This liquid cooling method involves the usage of a dielectric coolant that stays in liquid form during the cooling process. The coolant has a high coefficient of heat rejection and low thermal resistance, which protects the equipment submerged in the liquid.

Since the dielectric coolant is a better heat conductor than air, this kind of liquid cooling is well suited for high-density racks and is less expensive than two-phase immersion cooling.


Immersion cooling has been proven to be the best solution for industries needing to cool high-computing servers emitting a lot of waste heat.

Single-Phase Liquid Immersion Cooling, How Does It Work?

The principle of immersion cooling is immerging servers in a tank filled with a dielectric liquid.

The latter differs according to the type of system we’re using. In single-phase immersion, two types of liquid can be used. The hydrocarbon-based dielectric liquid, which is like mineral oil, and synthetic oil. Contrary to two-phase liquid, which is fluorocarbon-based liquid, the coolant in single-phase doesn’t boil and, therefore doesn’t undergo a phase change during the cooling process.

The waste heat is transferred from the components to the coolant. The latter is pumped to a heat exchanger where the heat is directly transferred to a cooler water circuit and sent back into the immersion tank.

Since the dielectric coolant is a better heat conductor than air, this kind of liquid cooling is well suited for high-density racks and is less expensive than two-phase immersion cooling.

Single-phase Immersed Dielectric Coolants

Single-phase Immersed Dielectric Coolants Properties

  • Ideal chemical inertness

  • Excellent thermal conductivity

  • Best electrical insulation  properties 

  • Excellent oxidation stability

  • Good system compatibility

Single-phase Immersed Dielectric Coolant Applications

1. Improve heat conduction efficiency

  •  Battery temperature drops

  •  Battery temperature difference decreases

  •  Dissipate heat and heat at the same time

  •  Extend battery life

2. Solve the overall problem of heat dissipation

  •  Battery system

  •  Motor system

  •  Power Electronics

3. Improve security

  •  After cell breakdown, it will not affect adjacent cells.

  •  After acupuncture of the core, it will not affect adjacent battery cells.

  •  No fire after battery core breakdown

4. Reduce mileage anxiety

  •  Suitable for super fast charging

  •  Reduce fast charging time

5. Medium properties 

  •  Non-toxic and biodegradable

  •  No effect on global warming

  •  Large-scale production is independent and controllable

  •  No corrosion to the equipment

OSi SiFOCool

Advantages of Single-Phase Immersion Cooling?

● Increase power rack density: The components in the server can be placed closer to each other therefore requiring less space because the heat generated is significantly reduced with immersion cooling. This enables high-density rack designs.

Reduce energy usage: Compared to traditional air cooling systems, single-phase cooling greatly reduces the data center footprint by reducing or completely removing air cooling units. It is estimated that single-phase liquid can use 50% less energy than traditional air cooling.

Components lifespan: The lifespan of components is longer in immersion cooling thanks to the lack of temperature variations and lack of fans (which can possibly provoke vibrations).

Low maintenance: This cooling method does not require complex infrastructure, CRACs, CRAHs, or chillers making it very effective and low maintenance.

Reduce PUE: Single-phase liquid can claim a PUE of 1.03 as opposed to 1.02 with two-phase immersion cooling and around 1.6 with air cooling.

Reduce TCO: Single-phase immersion cooling being a fanless system, air cooling infrastructure is reduced, greatly diminishing the total cost of ownership (TCO).

Safety & Storage

  • Customers should review the latest MSDS and label for product safety information, safe handling instructions, personal protective equipment if necessary, and any special storage conditions required for safety. MSDS is available at your request.

  • Keep away from heat and open flame. When stored at or below 35 ℃ in the original unopened containers, this product has a usable life of 12 months from the date of production.

Typical Technical Data

The values below are not intended for use in preparing specifications. Please confirm with us before writing specifications on this product.

ItemUnitSiFOCool D-1SIFOCooI D-2SiFOCool D-3
Chronic toxicity TWA
Hazard dedaration
Swallow may harmfulSwallow may harmfulSwallow may harmful
Ozone depletion potential
Global warming potential
Close to 0Close to 0Close to 0
Flash point176161.9201.7
Ignition point194182220
Spontaneous ignition point>350>300>360
Thermal Stability decomposition temperature>300>300>300

service life

Dielectric constant
Dielectric loss factor@90℃
Dielectric strengthKV/0.1 inch54.957.461.9
Volume resistivity@90℃Ohm. cm9.7*10¹³5.8*10¹³9.4*10¹³
Thermal conductivityW/m* K0.1640.1530.169
Specific heat capacity@40℃J/q* K2.2012.2512.113
Specific heat capacity@60℃J/Kq* K223122912153
Coefficient of thermal expansion10-31/K1.104241.125321.09365

ItemUnitSiFOCool D-1SiFOCool D-2SiFOCool D-3
Kinematic viscosity@100℃mm²/s2.581.793.196
Kinematic viscosity@ 60℃mm²/s6.154.257.105
Kinematic viscosity@ 40℃mm²/s9.185.4612.43
Kinematic viscosity 20℃mm²/s18.1212.97325.32
Density@ 100℃Kg/m³753738.6759.4
Density@ 60℃Kg/m³778.3762.3784.7
Density@ 40℃Kg/m³791.3778.6797.6
Density@ 20℃Kg/m³806.4790.2810.7
Distillation Initial boiling point284280290
Distillation range 2%Distillate temperature306.5290310
Surface tensionDyne/cm≥20≥20≥20
Pour point<-60<-60<-60
The solubility of waterppm≤20≤20≤20
Acid valuemg/g0.0390.0270.021

Remarks: This technical data sheet is only used for internal quality control within OSi Holding Limited. All rights reserved. We are prepared to customize and validate new immersion cooling fluids to your needs.

Single-phase Immersed Dielectric Coolants

Related Products