Abstract: A method for determination of battery parameters comprises the following steps: the determination of multiple roundtrip battery for a number of different pairs of charging and efficiencies discharging battery C-rates/P-rates, solving a nonlinear optimisation problem to obtain one-way efficiencies, and finding a charging and discharging characteristics for selected charging and discharging C-rates/P-rates. The obtained characteristic curves can reveal the actual current/power that is charged/discharged into/from the battery when the battery is charged/discharged with selected current/power from/to an external source/sink. The characteristic charging/discharging curves used can be for determination of battery charge capacity, battery energy capacity, state-of-charge (SOC), state-of-energy (SOE), state-of-health (SOH), and other battery parameters.

Abstract: A resonator absorber with adjustable acoustic characteristics made in the form of a cuboid with sidewalls and with an open upper face that is covered by two identical movable perforated plates to allow partial overlapping of the the plates. Each plate is equipped with bores forming a planar binary amplitude diffusor by using a maximum length pseudorandom binary sequence mapped to 2D space to determine the bore position. Bores are arranged in rows which do not overlap between plates. The resonator absorber has six cavities of different geometry situated below the perforated plates, where five cavities simultaneously change the volume with movement of the perforated plates. The resonator absorber is useful for tuning the acoustic characteristics of the environment.