The fuel cell is one option for balancing mobility and climate protection in the future. MANN+HUMMEL also supplies tailor-made filtration solutions for hydrogen propulsion systems. The ion exchange filters from the new IonFree modular kit reliably protect the fuel cell stack against dangerous short circuits and reduce system costs.

A fuel cell consists of several bipolar plates that are combined to form one stack. The stack is a power pack that stands out as new energy source with a remarkable range. A precondition is that the stack is consistently protected. This is because harmful particles and gases, water droplets and unsuitable humidity can cause considerable to irreversible damage to the fuel cell stack in the vehicle. MANN+HUMMEL meets these challenges with well thought-out products and supports the development and establishment of this clean drive system with its extensive filtration expertise. To protect the fuel cell, MANN+HUMMEL offers not only the air induction system for the cathode path, but also coolant particle filters and ion exchange filters for the cooling circuit.

In addition to external influences, the performance of the fuel cell stack can also be severely limited by the coolant inside the system. It dissipates the heat, but also acts as an electrical insulator as long as the conductivity of the fluid is low. However, the various components in the system constantly release ions. The result is an increased conductivity of the coolant. This can result in a short circuit destroying the system. The installation of an ion exchange filter in the cooling circuit is therefore essential.

Flexible ion exchange filter

The MANN+HUMMEL IonFree modular kit convinces with its modular housing concept. Customers can choose from eight variants depending on the application. Two different sizes are available: The medium capacity of 820 milliequivalents is ideal for passenger cars, while the high capacity of 1,190 milliequivalents is used in the heavy duty sector. While the passenger car variant has one mounting bracket, the heavy duty variant is supplied with two mounting brackets. The IonFree modular kit also offers a choice of two stud type geometries. The hose connection or the VDA coupling can be arranged at an angle of 90 or 180 degrees to each other. This means that the IonFree ion exchange filter can be used in a wide range of ambient conditions and installation spaces. The materials used are suitable for use in fuel cell applications.


Ion exchange filters with medium capacity of 820 milliequivalents

Ion exchange filters with high capacity of 1,190 milliequivalents

Stud type as hose connection or VDA coupling

Stud angle of the stud types in 90 or 180 degrees

Perfectly balanced ion exchange resin

The heart of the ion exchange filter is the ion exchange resin of highest purity. It is contained in a cartridge, which has stainless steel sieves at the inlet and outlet. These prevent resin particles from entering the cooling circuit. The cooling liquid flows in at the bottom and passes through the mixed bed of anion and cation resin. The MANN+HUMMEL engineers have adjusted the mixing ratio of the ion exchange filter IonFree to give it a high specific capacity and good ion exchange kinetics. Mechanical and thermal stability is ensured in the typical application area of the fuel cell.


In addition to their performance, the ion exchange filters of the IonFree modular kit convince due to their simple handling. Thanks to the flat cover of the cartridge, the cartridge can be changed directly and without loss of cooling water. The mounting bracket can be rotated and moved and is therefore flexible in its position. Thanks to the standard component concept, customers incur only low development and tooling costs. Production and validation meet the demanding automotive standards. Due to the advantages described above, the IonFree modular kit is versatile and therefore meets customer as well as market requirements.

MANN+HUMMEL Ion exchange filter

Advantages at a glance:

  • Prevents short circuits in the system
  • Modular housing concept
  • Best mechanical and thermal stability
  • Simple and clean service
  • Production and validation according to automotive standards
  • Use of special materials for use in fuel cell applications
Flyer IonFree

Read more about the MANN+HUMMEL modular IonFree kit.