This presentation describes the design process and functionality of a portable two-way solar charger prototype, achieving an energy density of 571 Wh∙kg-1 during a typical three-day infantry mission. The device may instantaneously charge up to two Li-ion MR-2791 batteries, supporting plug-and-play operation. The system consists of a lightweight custom solar panel, based on 20%-efficient monocrystalline photovoltaics, and an intelligent power-processing module, supporting both maximum power point tracking (MPPT) of the solar panel and multimode charging of Li-ion packs while instantaneously communicating with the batteries. Experimental results of system testing under real outdoor conditions are presented to demonstrate the device's functionality and energy yield capabilities.