Siemens to reduce battery recharging times to 6 minutes

The EDISON consortium, a Denmark-based collaborative aimed at developing an intelligent infrastructure that will make possible the large scale adoption of electric vehicles powered by wind energy, includes the Technical University of Denmark (DTU) and its Risø-DTU research center, as well as Denmark’s Dong Energy and Østkraft power utilities, the Eurisco research and development center, and IBM. In the EDISON project, various working groups are responsible for developing all the technologies needed for electromobility.

E.D.I.S.O.N. is an abbreviation for "Electric vehicles in a Distributed and Integrated market using Sustainable energy and Open Networks". The EDISON project is an international research project partly publicly funded through the Danish transmission system operator (TSO)’s research programme FORSKEL. The total budget is approximately 49 million DKK, where 33 million come from FORSKEL.

In the EDISON project Danish and international competences will be utilised to develop optimal system solutions for EV system integration, including network issues, market solutions, and optimal interaction between different energy technologies. Furthermore, the Danish electric power system provides an optimal platform for demonstration of the developed solutions.

Electric vehicles (EVs) provide a unique opportunity to reduce the CO2 emissions from the transport sector. At the same time, EVs have the potential to play a major role in an economic and reliable operation of an electricity system with a high penetration of renewable energy. EVs will be a very important balancing measure to enable the Danish government’s energy strategy, which implies 50% wind power penetration in the electric power system.

An EV will be a storage device for smoothing power fluctuations from renewable resources especially wind energy and provide valuable system services for a reliable power system operation. With the proper technology the cars can run on wind power and at the same time enable an increased share of RES in the power system for supply of the conventional electricity demand, and thereby, provide an overall economic, reliable, and sustainable energy system.

Siemens is mainly responsible for fast-charge and battery replacement systems. "Siemens’ portfolio already contains many components that we are now adapting and reprogramming," says Sven Holthusen, who is responsible for the EDISON project at Siemens’ Energy Sector.

A major obstacle to electromobility is the length of battery recharging times. With this in mind, Holthusen and his colleagues are working on a fast-charge function that operates with much higher voltages and currents—initially with 400 V and 63 A. This provides a 43.5 kw rapid charging connection that would allow fast charges of around 20 minutes. Holthusen’s approach is considered to be realistic since 400v/63A is already a common standard for industrial 3 phase installations and many European households already have a 400-V connection in the basement or other storage areas for electric ranges and other devices.

"We go a great deal further in our tests, however, in order to determine what’s possible," says Holthusen. More specifically, he wants to raise charging power to as much as 300 kW so that batteries can be recharged in six minutes. Electrics would then be on a par with conventional vehicles. Lithium-ion batteries with such fast charging capability are expected to be ready for market launch in the near future. However, new battery technologies will have to be developed if a car is to be charged in as little as three minutes.