BATTERY TEMPERATURE CONTROL APPARATUS, BATTERY SYSTEM, ENERGY STORAGE SYSTEM AND BATTERY TEMPERATURE CONTROL METHOD

Provided are a battery temperature control apparatus, a battery temperature control method and a battery system. The battery temperature control apparatus includes first to n cooling fans provided in a one-to-one relationship to first to n battery modules connected in series, first to n slave management units provided to the first to n battery modules in a one-to-one relationship, and a master management unit. n is a natural number of 2 or greater. The master management unit determines battery temperature information including first to n temperature values and a first reference value. The first to n temperature values indicate temperatures of the first to n battery modules. The first reference value is an average or a median of the first to n temperature values. The master management unit controls a rotation speed of each cooling fan based on the battery temperature information.