The present disclosure relates to estimation of battery parameters, including SOC and SOH using a plurality of particles, each of which represents at least one parameter and at least one state of a battery system. A system model may simulate the battery system using processing logic. Each of the plurality of particles may propagate through the system model to generate a plurality of modeled particle values, each of which may be compared to a measurement of an electrical parameter of the battery system. Each particle may be weighted based upon a comparison of the modeled particle value and the measurement. A successive plurality of particles may be generated based upon the weight assigned to each of the plurality of modeled particle values. A number of iterations may be performed to generate a tuned plurality of modeled particle values, upon which an estimated parameter of the battery system may be based.