Abstract: Techniques are described through which continuous gapless voltage measurements can be synchronized between devices with independent clock sources on an asynchronous bus by slightly adjusting a speed of a local clock source for a period of time. Also, a read-out technique is described through which the synchronous measurements can be read out in a coherent way. These techniques can allow a high-accuracy time-average of the battery cell voltage (or fuel cell voltage) to be reconstructed, while allowing the same results to be synchronous across an entire battery stack, for use in instantaneous voltage/current diagnostics or calculations.

Abstract: A system for measuring a complex impedance associated with an arrangement of battery or fuel cells in an energy storage system may include a controller, a current measurement device, and voltage measurement devices. The current measurement device may be shared by the cells for measuring a test current provided to the cells. The voltage measurement devices may be respectively coupled across corresponding cells. The controller, the current measurement device, and the voltage measurement devices may be coupled together using a DC isolated bus. The controller may determine a respective complex impedance of corresponding groups of the cells using a complex voltage measured by a respective voltage measurement device coupled across a corresponding group of the cells and a complex current measured by the complex current measurement device.

Abstract: A circuit may include a source of electrical energy and a plurality of current loads. Each load may be of a different amount. For each current load, a resistance may be in series between the source and the current load. The resistance may be weighted inversely proportional to the amount of the current load with respect to the other resistances. For each resistance, an integrator may generate an integrated output representative of an integration of the current traveling through the resistance. A summer may generate a summed output which is representative of the sum of each of the integrated outputs, weighted inversely proportional to the resistance that is associated with the integrated output.

Abstract: A circuit may include a source of electrical energy and a plurality of current loads. Each load may be of a different amount. For each current load, a resistance may be in series between the source and the current load. The resistance may be weighted inversely proportional to the amount of the current load with respect to the other resistances. For each resistance, an integrator may generate an integrated output representative of an integration of the current traveling through the resistance. A summer may generate a summed output which is representative of the sum of each of the integrated outputs, weighted inversely proportional to the resistance that is associated with the integrated output.