The rapid growth of electric vehicles (EVs) has increased the demand for efficient and intelligent charging systems capable of supporting modern power grids. This paper presents the design and simulation of a bidirectional battery charger that enables Grid-to-Vehicle (G2V), Vehicle-to-Grid (V2G), and active filter operations within a single integrated system. The proposed configuration consists of a bidirectional AC–DC converter connected to the grid and a bidirectional DC–DC converter interfaced with the battery through a regulated DC link. An LCL filter is employed to reduce harmonic distortion and ensure high-quality grid current. A control strategy based on pulse width modulation (PWM) and reference current polarity is implemented to achieve smooth transition between operating modes. In G2V mode, the system provides controlled battery charging with near unity power factor, while in V2G mode, stored energy is effectively supplied back to the grid. Additionally, the system operates as an active filter to compensate for harmonics caused by non-linear loads. Simulation results demonstrate stable DC link voltage, reliable bidirectional power flow, and improved power quality. A hardware prototype with microcontroller-based control and Bluetooth communication further validates the practical feasibility of the proposed system.