A battery system can include an evaporation chamber and condenser. One or more battery cells can be immersed in a fluid where the battery cells and the fluid are housed in the evaporation chamber. The condenser can be fluid connected to the evaporation chamber through one or more vapor channels and one or more liquid channels. When the battery cells charge and discharge, heat dissipated by the battery cells is absorbed by the fluid, causing the fluid to change from liquid to vapor. The vapor travels through the one or more vapor channels into the condenser where the vapor changes back to liquid and returns to the evaporation chamber through the one or more liquid channels. The thermal management solution is a self-sensing and self-regulating system.