The present technology relates to a battery cell jig including film-type pressure sensors, and a method of measuring a swelling of a battery cell using the same. According to the present invention, by using film-type pressure sensors, the volume of the measuring apparatus can be reduced, and abnormal degeneration of the battery cell by the pressure difference for each location of the battery cell can be prevented.

A module strain estimating apparatus, including: a module information obtaining unit configured to obtain a plurality of numerical information for a battery module; and a processor configured to: receive the plurality of numerical information from the module information obtaining unit, generate a first profile representing a correspondence between a force applied from the inside to the outside of the battery module and a strain of the battery module, and a second profile representing a correspondence between the force and a stress of the battery module based on a preset learning module and the plurality of numerical information, generate a third profile representing a correspondence between the strain and the stress of the battery module based on the first profile and the second profile, and estimate the strain of the battery module according to the stress of the battery module based on the third profile.

A method is for replacing a rechargeable battery that is considered as an unsatisfactory rechargeable battery that needs replacing in an assembled battery in which rechargeable batteries are stacked and restrained in a row and electrically connected in series or in parallel. The method includes removing of finding at least one of the rechargeable batteries to be an unsatisfactory rechargeable battery in the assembled battery and removing the unsatisfactory rechargeable battery, and installing a satisfactory rechargeable battery, which has little deterioration, on at least one end of the row of the rechargeable batteries, in a row direction, in the assembled battery from which the unsatisfactory rechargeable battery has been removed.

A method for testing a mechanical performance of a lithium ion battery electrode based on a nano-indentation technology includes following steps: connecting an assembled lithium ion battery with an electrochemical test device and setting different test working conditions, so that cyclic charge and discharge experiments are performed on the battery to obtain an attenuation curve of a battery capacity; disassembling the battery and taking out the electrode; scraping some powder from a surface of the cyclic electrode plate and an initial uncyclic electrode plate, and laying down the powder in cold mounting molds separately, pouring the cold mounting solution into the molds; taking out the samples from the molds respectively after the liquid is completely cured and cooled; detecting a mechanical performance after polishing the samples surfaces and analyzing the mechanical performance decay rule of the electrodes.

An apparatus and method for testing a secondary battery. The apparatus includes a test path, test terminals provided at two ends of the test path and electrically connected to a positive terminal and a negative terminal of the secondary battery respectively, a sensor unit provided on the test path and configured to measure a discharge current of the secondary battery, a constant voltage generation unit provided on the test path and configured to maintain a constant voltage between the secondary battery and the sensor unit, and a control unit configured to receive data indicating the discharge current from the sensor unit, measure an inflection point on a profile of the discharge current, measure an intensity of the discharge current on the basis of the inflection point, and test a level of self-discharge of the secondary battery based on the intensity of the discharge current.

In some embodiments, a battery management system is provided. The battery management system comprises a connector for electrically coupling a battery to the battery management system, at least one sensor configured to detect a battery state, a programmable chip configured to control at least one of charging and discharging of the battery, and a controller device. The controller device is configured to receive at least one battery state from the at least one sensor; provide the at least one battery state as input to a tanks-in-series model that represents the battery; and provide at least one output of the tanks-in-series model to the programmable chip for controlling at least one of charging and discharging of the battery.

An inspection device (20) for inspecting a structure body (10) including a pair of electrodes and a separator disposed between the pair of electrodes is provided, the inspection device (20) includes: a measurement unit (30) including a direct-current constant voltage generator (32) that generates a constant inspection voltage applied to the pair of electrodes, and a detection circuit (34) that detects a current value between the pair of electrodes resulting from the application of the inspection voltage; and a processing unit (50) that determines whether the structure body (10) is defective or non-defective based on the detected current value, and the processing unit (50) has a function that, if two or more points at which a ratio (ΔI/Δt) of a current value variation amount (ΔI) to a time variation amount (Δt) varies from a value of no less than 0 to a negative value are observed or no point at which the ratio (ΔI/Δt) varies from a value of no less than 0 to a negative value is observed during a period of time immediately after the application of the inspection voltage until the current value becomes constant, determines the structure body (10) as a defective product, and an auxiliary function that obtains a peak current value I.sub.peak, a peak current appearing time t.sub.peak and a current area S.sub.I of a current waveform representing variation in current value I over passage of time t, and if any one of the peak current value I.sub.peak, the peak current appearing time t.sub.peak and the current area S.sub.I deviates from a preset threshold value including an upper limit value and a lower limit value, determines the structure body as a defective product.

Provided are a method for designing an electrode for a lithium secondary battery comprising measuring the electrical conductivity of an electrode with an alternating current to determine whether an electrical path in the electrode has been appropriately formed, and a method for manufacturing an electrode for a lithium secondary battery comprising the same. According to the present invention, it is possible to determine the content of a conductive agent in the electrode using the same.

A method of evaluating a power storage device includes at least [a] to [f] below. [a] A power storage device is prepared. [b] A charge level of the power storage device is adjusted to produce a first potential difference between a positive electrode and a negative electrode. [c] The positive electrode or the negative electrode is selected as a reference electrode. [d] After the charge level is adjusted, an operation to insert a conductive rod-shaped member into a stack portion along a direction of stack of the positive electrode and the negative electrode is performed while a second potential difference between the reference electrode and the rod-shaped member is measured. [e] The rod-shaped member is stopped. [f] The power storage device is evaluated based on a state of the power storage device after the rod-shaped member is stopped.

Discussed is a system for managing a state of a battery, the system including: a user terminal to set location information about a location at which the battery is stored and output the set location information; a battery information obtaining device connected to the battery and to obtain battery information including at least one of voltage, SOC, and SOH of the battery and output the obtained battery information; and a performance detecting device connected to the user terminal to receive the set location information, connected to the battery information obtaining device to receive the obtained battery information, and to determine a target location at which the battery is stored, obtain environment information of the determined target location, set reference state information of at least one reference cell stored around the determined target location, and detect performance of the battery.