Power loss determining method for e.g. lithium ion battery, involves operating energy storage with alternating current, measuring current and voltage at storage, and determining power loss of storage using measured current and voltage

摘要

The method involves operating an energy storage (101) with alternating current, and measuring current and voltage at the energy storage. An open-circuit voltage is filtered from the measured voltage by filters (104) e.g. high pass filters and/or band pass filters (105, 106), and an interference signal is filtered from the measured current and voltage by the filters. Amplitude of the alternating current is selected such that a reference value of power loss of the energy storage is achieved. The power loss of the energy storage is determined using the measured current and voltage. Independent claims are also included for the following: (1) a method for adjusting a test bench depending on power loss of an energy storage (2) a device for determining power loss of an energy storage.