The present invention includes self-contained, rechargeable power systems for areas having unreliable electrical grids or no electrical grid at all, and methods related thereto. The system may include one or more solar panels of various sizes to provide an off-grid power generation source, battery receivers for receiving batteries of various chemistries, and a control circuitry that is operable to detect the voltage and/or current output of the batteries that are installed in the system to determine their specific battery chemistry and then adjust the charge algorithm of the batteries to optimize both the charge capacity and the cycle life of the batteries. The control circuitry may also be operable to switch configurations of the solar panels and/or the batteries to optimize performance of the system. The system may be operable to power one or more light emitters and/or external electronic devices connected through the system by a charge port.