Unravelling Polymers

The Definitive Blog on Polymers by Poly Fluoro Ltd.

PTFE Battery Separators - An Essential Insulating Media

The advancement of electronics in our daily lives has accelerated recently with the advent of IOT and electric vehicles. In all these applications, the one feature that is of paramount importance is the battery.

An enhanced battery life and performance appears to be the thing that sets a device apart from its peers. We evaluate our mobile phones and even our electric vehicles on the merit of how far they can go on a single charge. Furthermore, we need the battery life to stay consistent over the lifetime of the product and not dull out after one or two years of operation.

If industry sources are to be believed, the average life of an electric vehicle would be 400,000Km, as against the average of 200,000Km in today’s fuel-powered vehicles. It is suggested that we would not look to replace an electric vehicle (for performance-related factors anyway) for at least 15 years. Obviously, if the battery needs replacement every 2-3 years, this poses a problem. Even if a consumer wishes to trade in their old vehicle for a new one, the resale value of the older vehicle will ride heavily on the battery performance.

In an attempt to look for cheaper, more effective and light-weight solutions to this problem, PTFE has emerged as an ideal medium for insulating the insides of lithium-ion batteries. Battery separators are essential for ensuring that the battery does not discharge internally, reducing the effectiveness of a single charge. They also ensure that while charging, a battery does not accidentally short circuit internally.

PTFE films have several properties that make them ideal for this application:

  1. High dielectric breakdown voltage – the breakdown voltage of PTFE can be as high as 150KV/mm. This means that a thin film of PTFE can perform the insulative function of a much thicker layer of regular insulation
  2. Light-weight – although PTFE has a high density when compared with other polymers (~2.25 g/cm3), it is light when considering that a 40-50 micron film is all that is needed to make an effective medium. In an age when devices are getting more compact, this becomes an even more critical characteristic of the material
  3. Chemically inert – because PTFE does not react with other chemicals (barring molten alkalis at elevated temperatures), it can be used with no concern that it will disintegrate over time
  4. Zero-static discharge – PTFE does not allow any current to pass through or along its surface. This extreme insulative ability ensures that there is no ‘leakage’ of current within the battery, which can cause it to slowly discharge even while idle.
  5. Available in variants – both skived PTFE films and ePTFE Films can be used as separators, depending on whether there is a requirement for porosity or not. Furthermore, PTFE films can also be infused with carbon to give anti-static properties, which may or may not be a requirement depending on the equipment design.

It is a known fact that insulation and electronics go hand in hand. As our dependence on electronic devices grows, so too does our need for stable, cost-effective and efficient insulation. PTFE – due to its incomparable properties as an insulator – should see its demand increase substantially, as more applications will require its unique properties to stay effective.

PTFE Tubing

PTFE Tubes are known for their versatility and durability.

As a material, it comes with the numerous properties of PTFE, including temperature resistance, chemical resistance, electrical insulation and high-strength.

The high ratio of strength (both tensile and electrical) to weight gives us the option of using a much smaller tube of PTFE to do the same task that might require a lot more of a less capable material.

A high burst pressure means that both pneumatic and hydraulic systems would benefit tremendously from the use of PTFE tube. Similarly, a dielectric breakdown strength in the region of 150KV/mm implies that even a wall thickness as thin as 0.5mm allows for a breakdown resistance of 75KV.

Chemical lines, which often require a material that does not in any way react with the chemical inside it, benefit from the inert nature of PTFE. This means that even in the event that some unknown chemicals are present in the fluid passing through the tube, there is no risk that the tube will corrode or in any way impart its own reaction with the chemical.

PTFE tubes are known by many names across the industry:

  1. PTFE Tubing
  2. PTFE Hose
  3. PTFE Pipe
  4. PTFE Sleeve
  5. PTFE Sheath
  6. PTFE  Liners

They are all part of the same process and extruded in the same manner.


PTFE Tubing finds application in nearly every industry

Please visit our website for more details or email us: enquries@polyfluoroltd.com


Expanded PTFE (ePTFE) Gasket Tapes

Expanded PTFE (ePTFE) Gasket Tape is increasingly becoming the preferred material of choice for any application requiring an on-site solution to both prevent and arrest leakages.

The material’s superior sealing properties combined with the ability to withstand both high temperatures and nearly all corrosive chemicals make it the obvious choice for engineers looking for a long term solution to sealing without worrying about the durability of the sealing material.

ePTFE Gasket Tapes are also known as the following:

  1. Joint Sealant Tapes
  2. Soft PTFE Tapes
  3. Form-in-place Gasket Tape
  4. Gore Gasket Tape
  5. Expanded PTFE Sealing Tape
  6. Self-adhesive Gasket Tape

The fact that there are so many different names poses a challenge to market this product – since each end user may have their own terminology and thus search online accordingly.

The versatility of ePTFE Gasket Tapes extends across multiple industries, as shown in the info-graphic below.

Expanded PTFE (ePTFE) Gasket Tape

The above photo shows the typical application of ePTFE Gasket Tape. Although this shows the joint sealant being applied around a metal flange, the tape is equally adept at sealing weaker materials such as glass or plastic. This is because the sealing effectiveness can be attained at low torques, allowing a completely air-tight seal even if the option to tighten around the medium is limited.

Find out more about the applications and installations of Expanded PTFE (ePTFE) Gasket Tape on our website