Flame-retardant polypropylene films from CMC - protective shield for the battery

Polypropylene (PP) has proven itself as a versatile and cost-effective plastic in many areas of industry. Its properties such as lightness, flexibility and chemical resistance also make it an ideal material for use in electric vehicles.

Polypropylene is also an excellent electrical insulator even under adverse conditions (moisture, high voltage, long-term use). Films or die-cut parts made from these films can be used in a wide temperature range.

A second advantage of the films from CMC Klebetechnik is their flame retardancy. This is because in the unfavorable case of a so-called "thermal runaway", i.e. the thermal runaway of a single cell, it quickly spreads without a fire barrier. Flame-retardant polypropylene films from CMC help to slow down or even prevent fire propagation. They form a barrier that reduces heat development and extends the time until the fire spreads.

In electric vehicles, for example, this reduces other measures that would be necessary to fulfil the international regulation GTR 20. According to this Global Technical Regulation, passengers in a vehicle must remain in the vehicle for at least 5 minutes after an incident. The StVZO also stipulates in §62 Electrical equipment of electrically powered motor vehicles that neither property nor persons may be damaged by electrical effects during normal operation of the vehicle. 

Adhesive tapes, films and die-cut parts made of flame-retardant polypropylene film from CMC Klebetechnik - battery applications

Flame-retardant polypropylene films are used in a wide range of applications in batteries for battery storage and vehicle batteries:

• Cell insulation: The foils serve as a separating layer between the individual cells to prevent short circuits and limit the spread of heat. The foils also serve as protection against residual currents in the event of insulation faults.
• Module insulation: At module level, the films protect against mechanical damage and contribute to the electrical and thermal safety of battery modules.
• BMS isolation: The electronic battery management system monitors and controls the entire battery and must be isolated from the high-voltage supply.
• Battery housings : The use of flame-retardant polypropylene films can provide additional protection for battery housings. The use of flame-retardant polypropylene films with a low weight provides an inexpensive additional electrical and fire protection benefit.
• Insulation of conductors : Thanks to their very good electrical properties, PP-TFR die-cut parts are also suitable for insulating conductors carrying high currents.
• Insulation in charging stations: Charging stations for electric vehicles also contain numerous electrotechnical components which, in addition to electrical insulation, require additional safety through excellent flame retardancy.

Advantages at a glance

• Lightweight construction: Polypropylene is a lightweight material that helps to reduce the weight of the vehicle.
• Cost efficiency: Flame-retardant polypropylene films are comparatively inexpensive.
• Formability: The films can be easily formed into the desired shape and also adapt to complex geometries. CMC Klebetechnik's die-cutting technology offers potential customers sample production from a quantity of one to several hundred thousand die-cut parts for testing purposes, which can also be 3D-folded.
• Safety: The most important advantage is increased safety. Flame-retardant polypropylene films make a significant contribution to preventing fires in batteries or at least slowing their spread.

Flame-retardant polypropylene films from CMC Klebetechnik GmbH play an important role in the safety of electric vehicles. They are an indispensable component of modern battery technologies and help to increase consumer confidence in electromobility. The combination of excellent electrical properties, a favorable price, low weight and very good processability make them an ideal solution for use in mobile and stationary battery storage systems (BESS).