Abstract: After charging or discharging is stopped, a reference timing (t0) is set, and a first timing (t1) at which battery voltage (V) changes by a unit amount (N) with respect to the reference timing (t0), and a second timing (t2) at which the battery voltage changes by twice more than the unit amount with respect to the reference timing (t0) are select and set. The ratio of the time difference (t2?t1) between the first and the second timing to the time difference (t1?t0) between the reference and the first timing is found as a voltage change parameter (R) corresponding to the rate of change of the change speed of the voltage battery. An estimation device considers the change rate determined by the parameter is considered to be unchanged during an electrical current non-passage, and estimates a stable open circuit voltage at an object timing in future after the second timing.

Abstract: After charging or discharging is stopped, a reference timing (t0) is set, and a first timing (t1) at which battery voltage (V) changes by a unit amount (N) with respect to the reference timing (t0), and a second timing (t2) at which the battery voltage changes by twice more than the unit amount with respect to the reference timing (t0) are select and set. The ratio of the time difference (t2?t1) between the first and the second timing to the time difference (t1?t0) between the reference and the first timing is found as a voltage change parameter (R) corresponding to the rate of change of the change speed of the voltage battery. An estimation device considers the change rate determined by the parameter is considered to be unchanged during an electrical current non-passage, and estimates a stable open circuit voltage at an object timing in future after the second timing.

Abstract: An internally geared hub is provided with a hub axle, a hub shell, a driver, a planetary gear mechanism and a gear changing mechanism. The hub shell rotates freely about the hub axle. The driver rotates freely relative to both the hub axle and the hub shell. The planetary gear mechanism is operatively connected between the hub shell and the driver. The planetary gear mechanism includes a plurality of driver rotation transmission paths that transmits rotation of the driver in a prescribed operating direction to the hub shell, and a hub shell rotation transmission path that transmits rotation of the hub shell in the prescribed operating direction to the driver. The gear changing mechanism is operatively connected the planetary gear mechanism for selectively establishing one of the driver rotation transmission paths or the hub shell rotation transmission path.

Abstract: An internally geared hub is provided with a hub axle, a hub shell, a driver, a planetary gear mechanism and a gear changing mechanism. The hub shell rotates freely about the hub axle. The driver rotates freely relative to both the hub axle and the hub shell. The planetary gear mechanism is operatively connected between the hub shell and the driver. The planetary gear mechanism includes a plurality of driver rotation transmission paths that transmits rotation of the driver in a prescribed operating direction to the hub shell, and a hub shell rotation transmission path that transmits rotation of the hub shell in the prescribed operating direction to the driver. The gear changing mechanism is operatively connected the planetary gear mechanism for selectively establishing one of the driver rotation transmission paths or the hub shell rotation transmission path.