Magnets can be applied in many ways: Magnetic forces can move machines or make robot hands grasp objects. Valves are opened and closed by magnets, similar to small locks. It is also possible to bind magnetic particles to chemical or biological substances and to sort these substances or specifically guide them through microfluidic channels. In the area of mechanical engineering, solenoids are applied, which consume energy on a permanent basis, as they have to be passed by current in order to maintain their magnetic effect. Permanent magnets made of a magnetic material do not need any current, but also cannot be switched on and off. It would be desirable to influence the magnetic state of metallic or semi-conducting materials with the help of electric fields. In the future, this technology might be applied in magnetic storage media. However, the influence of electric fields is restricted to ultra-thin surface layers, such that magnetic forces are too small to use them for moving machine parts. Scientists of the KIT Institute of Nanotechnology (INT) have now developed a method to influence magnetic properties of materials in the entire volume. The method works analogously to electrochemical energy storage systems, such as accumulators. As electrode material, magnetic iron oxide nanocrystals are used. By means of charge and discharge processes, non-magnetic elements, such as lithium, intercalate. This intercalation is reversible and can be used to control the magnetic properties of the material.For this electrochemical control of magnetization, energy is required to change the state only, not to maintain magnetization. The switchable magnets might be used in microfluidics, analytics, microtechnology, and in particular in microrobotics in the future. KIT looks for partners for the further development and application of this technology.