Wireless charging for xEV – pronounced “ex-EV”and refers to pure electric vehicle (EV) or plug-in Hybrid (PHV) – is one of the hot areas of industry studies. The possibility to charge a vehicle without a cable would generate a number of advantages: automatic ‘hands-free’ charging, cable-free clean look of charging stations, and so on.
Would it ever be possible to charge a car’s battery without a cable?
“Yes, it is possible,” says Dr Ivo Teerlinck, an R&D expert of Toyota Europe. “Wireless charging of an electric vehicle or a plug-in Hybrid is not a dream.”
“Electricity is transmitted by magnetic induction between the transmitting coil on the ground and the receiving coil in the car.”
“This technology is a crucial step forward to cable-free electro mobility.”
However, car manufacturers can’t directly jump into commercialisation. “We first need to ensure customers’ peace of mind by establishing a globally harmonised standard for charging process and systems.”
“Without such a standard, customers of electro mobility will face the same frustration as with mobile phone chargers. Each time we buy a mobile phone we also have to buy a new charger, which may not be compatible with the next one we will buy in future either. In case of xEVs and their charging stations, the frustration would be much bigger.”
“Future customers of xEVs of any brand should be able to charge their vehicle easily anywhere. When buying and using an xEV, they should not bother about how to charge it.”
“For this purpose, all the charging systems around the world should be made in the same way and offer the same user experience. Car manufacturers, suppliers, standardisation bodies and governments must agree on one global standard.”
Toyota has been participating in the negotiations on the future standard. It is a huge challenge, but, there have been significant progresses lately.
Firstly, after five years of discussions between industry representatives within the official standardisation bodies’ framework (*), the very first version of technical guidelines has been agreed on this year which is called SAE TIR J2954.
“This is an important milestone, because the direction of the future standard has been narrowed down significantly, with some critical details frozen,” says Ivo. “It helps convince the standardisation community and governments that the industry is really starting to build a consensus. This is very positive.”
The target is to establish a globally harmonized standard in 2018. “It is a set of specifics which will determine how to make a wireless xEV charging system and how it works for customer. It will be based on technical options recognised by the industry and other stakeholders. It’s the ‘best way for everyone’”.
As a strategy for the next steps leading to the standard, a group of car manufacturers (Audi, BMW ,Daimler and Toyota, suppliers (BOSCH, Continental, Qualcomm, and WiTricity) and academia set up a Project STILLE earlier this year. This unique project is part of the funding programme Elektro Power II which is funded by the German Federal Ministry for Economic Affairs and Energy. The goal is to facilitate and support the further development of an interoperable global standard.
Reaching an agreement between manufacturers can be very difficult, with each of them trying to defend its own position on the grounds of its own data, technologies and interest at stake in their specific markets.
Project STILLE aims to create common data which all these members can unanimously support. .
Ivo says: “Usually, when the industry needs to reach an agreement, the standardisation body tries to facilitate it. The process typically starts by gathering data from each member manufacturer.”
“However, it is extremely difficult to reach agreement because each manufacturer tries to defend its own data.”
“STILLE’s approach is more strategic. Instead of gathering data, the STILLE members create common data together, starting from testing. All the member manufacturers know how the common data was made, so they can trust it. Such transparency makes it much easier to create one voice.”
“Hopefully, this approach will help smoothen the last stages of the discussions aimed at narrowing down from several options to the final specifications of the standard.”