ENERGY STORAGE SYSTEM COLD START POWER DISCHARGE ENHANCEMENT USING MULTIPLE BRANCH COOLANT SYSTEM

A system for enhancing cold start discharge power of a multi-cell rechargeable energy storage system (RESS) having battery cells connected in electrically parallel battery modules includes a cooling subsystem. The subsystem has a main coolant loop circulating coolant, multiple coolant branches arranged in parallel, and flow-valve(s) regulating and distributing coolant from the main loop across the branches. At least some coolant branches receive portions of the coolant from the main loop to adjust temperature of corresponding individual battery modules. An electronic controller detects when RESS temperature is at or below a predetermined value and increases temperature of coolant in the main coolant loop above the predetermined value via a heater. The controller also selects battery module(s) and identifies coolant branch(s) associated therewith. The controller further shuts off coolant flow into coolant branches of non-selected battery module(s) to exclusively heat selected battery module(s) and enhance RESS cold start discharge power.