In order to avoid global warming and city pollutions, the development of electric vehicles (EVs) such as electric cars and buses is of great importance. Wireless power transfer (WPT) helps in ease and reliability of charging the EV battery. This PhD will research high-efficiency wireless power transfer technologies for electric vehicle battery charging. Wireless power transfer is an effective way to transfer electrical power without cables connections. Efficiency is a very important factor when assessing the performance of wireless power transfer systems. This PhD project will look into using low-loss power electronics to improve the efficiency. A system level design optimisation will be carried out. Simulation and experimental results will be used to validate the designed system.