Provided is a secondary battery state output system capable of outputting the deterioration state of a secondary battery including a content satisfactory to a user in a timely manner. A state output system of the present invention is a system for outputting the deterioration suite of the secondary battery mounted on a user device used by the user, and includes an output unit which, when the most recent deterioration state of the secondary battery is determined to be deviating from a tendency, determines a detailed deterioration state indicative of a detailed deterioration state of the secondary battery based on information indicative of how the secondary battery had been used by the most recent time point, and outputs the most recent deterioration state and the detailed deterioration state.

Provided is a secondary battery state output system capable of outputting the deterioration state of a secondary battery including a content satisfactory to a user in a timely manner. A state output system of the present invention is a system for outputting the deterioration suite of the secondary battery mounted on a user device used by the user, and includes an output unit which, when the most recent deterioration state of the secondary battery is determined to be deviating from a tendency, determines a detailed deterioration state indicative of a detailed deterioration state of the secondary battery based on information indicative of how the secondary battery had been used by the most recent time point, and outputs the most recent deterioration state and the detailed deterioration state.

A method of diagnosing degradation of an electrode active material for a secondary battery including obtaining a first differential curve (dQ/dV) by differentiating an initial charge/discharge curve obtained by performing first charging and first discharging of the lithium secondary battery in a voltage range of 2.5 V to 4.2 V, and obtaining a second differential curve (dQ/dV) by differentiating a charge/discharge curve obtained by performing second charging and second discharging of the lithium secondary battery in a voltage range of 2.5 V to 4.2 V, and diagnosing whether a beta phase of the positive electrode active material has been formed by comparing maximum discharge peak values of the first differential curve and the second differential curve.

A current sensor includes a battery terminal portion that is conductive and is fastened to a battery post that extends along a first direction; a sensor unit that is located side by side with the battery terminal portion along a second direction that intersects the first direction and is electrically connected to the battery terminal portion to detect a current; and a housing that has an insulating property and embeds the sensor unit, in which the battery terminal portion includes a pair of plate-shaped portions, and the pair of plate-shaped portions are embedded in the housing with end portions on the sensor unit side in the second direction spaced apart from each other along the first direction.

A current sensor includes a battery terminal portion that is conductive and is fastened to a battery post that extends along a first direction; a sensor unit that is located side by side with the battery terminal portion along a second direction that intersects the first direction and is electrically connected to the battery terminal portion to detect a current; and a housing that has an insulating property and embeds the sensor unit, in which the battery terminal portion includes a pair of plate-shaped portions, and the pair of plate-shaped portions are embedded in the housing with end portions on the sensor unit side in the second direction spaced apart from each other along the first direction.

Disclosed are methods, systems, and devices for battery formation. A first set of pulses, having a first frequency, and that carry a net zero charge, are applied to a battery. After the first set of pulses are applied to the battery, a second set of pulses that carry a net positive charge are applied to the battery. The second set of pulses are either applied after expiry of a particular time period following the application of the first set of pulses, or based on some battery measurements. After the second set of pulses are applied to the battery, a battery parameter is measured, and based on the measured battery parameter, a third set of pulses, having a second frequency, and that also carry a net zero charge, are applied to the battery.

Disclosed are methods, systems, and devices for battery formation. A first set of pulses, having a first frequency, and that carry a net zero charge, are applied to a battery. After the first set of pulses are applied to the battery, a second set of pulses that carry a net positive charge are applied to the battery. The second set of pulses are either applied after expiry of a particular time period following the application of the first set of pulses, or based on some battery measurements. After the second set of pulses are applied to the battery, a battery parameter is measured, and based on the measured battery parameter, a third set of pulses, having a second frequency, and that also carry a net zero charge, are applied to the battery.

A storage battery management device includes a control unit. The control unit obtains a current value of a current flowing through a storage battery, a temperature of the storage battery, and a charging rate of the storage battery during a target period. The control unit determines an operation mode of the storage battery during the target period on the basis of the current value and the charging rate. The control unit estimates a degree of degradation of the storage battery during the target period on the basis of the operation mode and the temperature.

A storage battery management device includes a control unit. The control unit obtains a current value of a current flowing through a storage battery, a temperature of the storage battery, and a charging rate of the storage battery during a target period. The control unit determines an operation mode of the storage battery during the target period on the basis of the current value and the charging rate. The control unit estimates a degree of degradation of the storage battery during the target period on the basis of the operation mode and the temperature.

A battery system includes: a battery pack including a plurality of battery cells; and a battery management system for setting numbers to the battery cells by measuring cell voltages of the respective battery cells at a wake-up time, detecting a maximum cell voltage and a minimum cell voltage by periodically measuring the cell voltage of the respective battery cells after the wake-up, comparing the minimum cell voltage and the cell voltage of at least one first diagnosis target battery cell, comparing the maximum cell voltage and the cell voltage of at least one second diagnosis target battery cell, and diagnosing whether the diagnosis target battery cell is abnormal according to results of the comparison.