Kyowa Electric Wire Develops Al Litz Wire for Wireless EV Charging Coil

Kyowa Electric Wire, which is Osaka based electric wire and cable maker of Furukawa Electric Group, announced on Monday the company successfully developed aluminium litz wire. The aluminium litz wire weighs only a half of conventional copper litz wire. The firm expects the lighter weight litz wire is used for coils of wireless inductive charging system for electric vehicles (EVs). Kyowa Electric Wire plans to start sample supply to the users in February and commence the commercial production in the second half of fiscal 2012 ending March 2013. The initial sales target is 100 million yen per annum in fiscal 2013.

Kyowa Electric Wire’s aluminium litz wire consists of stranded aluminium wires those which are tin plated and enamel insulated. The company manufactures aluminium litz wire at Fukui plant, Japan. Aluminium wire is generally difficult to solder while tin plating helps the wire’s soldablity. The insulating material can be naturally removed by heat in soldering process. With the properties, the aluminium litz wire contributes to much shorter soldering lead time and lower productive cost for inductive coils.

Litz wire reduces the increase of AC resistance caused by skin effect when high-frequency current is applied to the wire. Then litz wire prevents temperature rise of conductors and contributes to electric devices’ efficiency improvement, downsizing and energy saving.

Kyowa Electric Wire aims to supply aluminium litz wire for such applications as secondary coils on EVs used for wireless inductive charging system, high-frequency devices, inverters, transformers, motors, power generators and heating equipments. Market of wireless EV charging system is expected to widen in and after fiscal 2014. The company targets sales expansion of aluminium litz wire to several hundred million yen per year eyeing the product supply to overseas customers as well.