XCell Fast Charger BC-X4000 is a digital LCD universal charger featuring microprocessor control. It is optimized for charging modern Li-Ion batteries and can charge all common 1.2V Ni-MH/Ni-Cd and 3.7V Li-Ion batteries, as well as devices with 5V voltage via USB connection. The charger supports various battery sizes, including AA, AAA, C, SC, 18650, 26650, 26500, 18490, 17500, 16340, 123A, 14500, and others.

It has a separate LCD display for each charging slot and a fast charging function adjustable up to 1000 mA per slot. The charger includes a test function for capacity checks, battery defect detection, and an adjustable charging speed. Simultaneous charging and testing are possible, with selectable display options during charging/testing, including charging current in mA, elapsed time, voltage in volts, and charged capacity.

Single slot control allows all functions to be set simultaneously and independently for each charging slot. The charger features overcharge protection with automatic switch-off after charging to prevent overcharging, along with an illuminated LCD display.