An on-board charging, OBC, device for an electric vehicle, comprising: a mains input comprising a power factor correction, PFC, converter; a mains-side DC/AC converter; a transformer having a mains-side coil and a battery-side coil; a battery-side AC/DC converter; a battery connector; and one or more bypass switches configured to galvanically connect the mains-side converter to the battery-side converter when closed; wherein the transformer is configured to be magnetically coupled to a TX pad of an external wireless power transmitter, WPT, such that power is received by the mains-side coil and the battery-side coil; wherein when the bypass switches are closed and the transformer is magnetically coupled to a WPT, power is sent to the battery connector through both the battery-side converter and the mains-side converter, the OBC device further comprises a mains-side resonant tank having a first capacitance and a first inductance, and a battery-side resonant tank having a second capacitance and a second inductance; and wherein values of the first capacitance and the first inductance of the mains-side resonant tank and the second capacitance and the second inductance of the battery-side resonant tank are selected to adapt the OBC device for operation with the mains input and operation with the WPT, wherein the values of the first capacitance and the first inductance of the mains-side resonant tank and the second capacitance and the second inductance of the battery-side resonant tank are selected in order to define the first resonant frequency of a CLLC resonant tank which is a combination of the mains-side resonant tank and the battery-side resonant tank for operation with the mains input as well as the second resonant frequency for operation with the WPT, and characterized in that the mains-side coil and the battery-side coil are arranged with a partial overlap to generate the first inductance of the mains-side resonant tank and the second inductance of the battery-side resonant tank simultaneously. a mains input comprising a power factor correction, PFC, converter; a mains-side DC/AC converter; a transformer having a mains-side coil and a battery-side coil; a battery-side AC/DC converter; a battery connector; and one or more bypass switches configured to galvanically connect the mains-side converter to the battery-side converter when closed; wherein the transformer is configured to be magnetically coupled to a TX pad of an external wireless power transmitter, WPT, such that power is received by the mains-side coil and the battery-side coil; wherein when the bypass switches are closed and the transformer is magnetically coupled to a WPT, power is sent to the battery connector through both the battery-side converter and the mains-side converter, the OBC device further comprises a mains-side resonant tank having a first capacitance and a first inductance, and a battery-side resonant tank having a second capacitance and a second inductance; and wherein values of the first capacitance and the first inductance of the mains-side resonant tank and the second capacitance and the second inductance of the battery-side resonant tank are selected to adapt the OBC device for operation with the mains input and operation with the WPT, wherein the values of the first capacitance and the first inductance of the mains-side resonant tank and the second capacitance and the second inductance of the battery-side resonant tank are selected in order to define the first resonant frequency of a CLLC resonant tank which is a combination of the mains-side resonant tank and the battery-side resonant tank for operation with the mains input as well as the second resonant frequency for operation with the WPT, and characterized in that the mains-side coil and the battery-side coil are arranged with a partial overlap to generate the first inductance of the mains-side resonant tank and the second inductance of the battery-side resonant tank simultaneously.