Abstract: A cathode for a lithium secondary battery includes a cathode current collector, a first cathode active material layer formed on the cathode current collector and including a first cathode active material and a first cathode conductive material, and a second cathode active material layer formed on the first cathode active material layer and including a second cathode active material that has an average particle diameter larger than that of the first cathode active material, and a second cathode conductive material. A content of the first cathode conductive material based on a total weight of the first cathode active material layer is greater than a content of the second cathode conductive material based on a total weight of the second cathode active material layer.

Abstract: An electrode assembly manufacturing apparatus and method according to one embodiment of the present invention includes a first table on which a first half jelly roll is stacked; a second table on which a second half jelly roll is stacked; a separator disposed on the first table and the second table; a first separator reel unwinding the separator in a direction to the first table; a second separator reel unwinding the separator in a direction to the second table; an electrode header providing a first electrode and a second electrode to the first table and the second table; a first motor moving the separator in a direction for covering the first electrode and the second electrode provided on the first table; a second motor moving the separator in a direction for covering the first electrode and the second electrode provided on the second table; and an assembly header providing the second electrode between the first half jelly roll and the second half jelly roll.

Abstract: A cathode for a lithium secondary battery includes a cathode current collector, and a cathode active material layer including a plurality of active material layers sequentially disposed on the cathode current collector which include different types of cathode active material particles from each other. DA determined by the present disclosure of an active material layer closest to the cathode current collector among the plurality of active material layers is 0.5 ?m or less.

Abstract: The present invention provides an apparatus and a method for evaluating performance of a battery and equipment for transporting the battery. The battery performance evaluation apparatus of the present invention includes: a temperature measurement unit for measuring an aging temperature of the battery; a voltage measurement unit for measuring a first open circuit voltage of the battery at the start of aging and measuring a second open circuit voltage of the battery at the end of aging; and a processor for calculating a delta voltage of a voltage drop using a difference between the first open circuit voltage and the second open circuit voltage measured by the voltage measurement unit, and determining normal or defective of the battery based on the delta voltage calculated using the aging temperature measured by the temperature measurement unit and an aging period between measurement times of the first and second open circuit voltage.

Abstract: Provided are a separator for a secondary battery, a manufacturing method thereof, and a lithium secondary battery including the same, having appropriate porosity and an appropriate pore size to lead to excellent strength and safety, and having excellent ion conductivity and resistance characteristics due to interconnected pore passages. The manufacturing method of a separator for a secondary battery includes: molding a separator manufacturing composition into a separator manufacturing sheet; and extracting a diluent from the separator manufacturing sheet with a polar aprotic organic solvent.

Abstract: Provided are a separator for a secondary battery, a manufacturing method thereof, and a lithium secondary battery including the same, having appropriate porosity and an appropriate pore size to lead to excellent strength and safety, and having excellent ion conductivity and resistance characteristics due to interconnected pore passages. In the separator for a secondary battery, an RS value represented by Equation 1 below is greater than 5 and less than 10: R S = P D × G ? Equation ? 1 ? wherein in Equation 1, RS denotes a separator performance index, P denotes an average porosity value (%) of the separator, D denotes an average pore diameter value (?m) of the separator, and G denotes an air permeability value (sec/100 cc) of the separator.

Abstract: A cathode for a lithium secondary battery includes a cathode current collector, and a cathode active material layer including a plurality of active material layers sequentially disposed on the cathode current collector which include different types of cathode active material particles from each other. DA determined by the present disclosure of an active material layer closest to the cathode current collector among the plurality of active material layers is 0.5 ?m or less.

Abstract: The present disclosure relates to a ceramic-carbon composite including a ceramic shell surrounding a hollow portion; and a carbon coating layer surrounding the ceramic shell, wherein the hollow portion is in a vacuum state, an electrode including the ceramic-carbon composite, and a secondary battery including the electrode. The ceramic-carbon composite of the present disclosure has excellent thermal barrier effect and electrical conductivity, and thus, when used in the electrode, non-ideal heat transfer between an electrode active material and an electrode current collector is blocked to prevent a thermal runaway phenomenon, to have an effect that can significantly improve safety of the secondary battery.

Abstract: An apparatus and a method for determining a defect of a battery cell are disclosed. The defect determination apparatus according to an aspect includes: a temperature measurement unit configured to measure an aging temperature of the battery cell; a period determination unit configured to determine an aging period of the battery cell; an SOC determination unit configured to measure and determine a state of charge (SOC) of the battery cell at the start of aging; a voltage measurement unit configured to measure open circuit voltages (OCVs) of the battery cell at the start of aging and at the end of aging; and a defect determination unit configured to determine whether the battery cell is defective based on the aging temperature, the aging period, the SOC at the start of aging, the OCV at the start of aging and the OCV at the end of aging.

Abstract: A battery cell includes a casing provided with an accommodation space; and an electrode assembly accommodated in the accommodation space and contacting the casing. The electrode assembly may include a negative electrode including a first current collector and a negative electrode mixture applied to the first current collector; a positive electrode including a second current collector and a positive electrode mixture applied to the second current collector; a separator interposed between the positive electrode and the negative electrode; and a guide member accommodating at least one of the negative electrode and the positive electrode and pressurized or stretched by at least one of the negative electrode and the positive electrode to contract or expand.

Abstract: A battery cell includes a case provided with an accommodation space; and an electrode assembly accommodated in the accommodation space and contacting the case. The electrode assembly includes a negative electrode including a plurality of negative electrode current collectors, on which a negative electrode mixture is coated, and a deformation absorbing member interposed between the plurality of negative electrode current collectors; a positive electrode including a positive electrode current collector on which a positive electrode mixture is coated; and a separator interposed between the negative electrode mixture and the positive electrode mixture. The deformation absorbing member may be interposed between surfaces, opposing a surface on which the negative electrode mixture is coated, of the negative electrode current collector and may be pressurized or stretched by at least one of the negative electrode and the positive electrode to contract or expand.

Abstract: Exemplary embodiments of the present disclosure provide a separator for a secondary battery, capable of preventing heat from transferring to an adjacent region in an electrode even when non-ideal heat is generated by an electrode active material, a trigger point of thermal runaway. A separator for a secondary battery according to the present disclosure includes a porous polymer substrate and a ceramic layer provided on at least one surface of the porous polymer substrate. The ceramic layer includes a ceramic composite. The ceramic composite includes a hollow portion, a ceramic shell surrounding the hollow portion, and a doping material dispersed in the ceramic shell. The hollow portion is in a vacuum state.

Abstract: A battery cell sealing apparatus includes: a first sealing block and a second sealing block pressurizing a case, provided with an accommodation space in which an electrode assembly is accommodated, to seal the case; a moving unit connected to at least one of the first sealing block and the second sealing block and moving at least one of the first sealing block and the second sealing block; and a heating unit connected to the first sealing block and the second sealing block and supplying heat energy to the first sealing block and the second sealing block. The first sealing block and the second sealing block may include a plurality of block members, and may pressurize the case with the plurality of block members to form a plurality of sealing portions on the case.

Abstract: A battery cell includes a case having an accommodating space, an electrode assembly including an anode, a cathode, and a separator accommodated in the accommodating space, a first sealing portion formed outside the accommodating space in the case, and sealing the case, and a second sealing portion including a region of the case present outside of the first sealing portion, positioned farther away from the accommodating space than the first sealing portion, and sealing the case. The first sealing portion is formed to be inclined between the accommodating space and the second sealing portion.

Abstract: A lithium secondary battery according to embodiments of the disclosed technology includes a pouch that includes a first pouch case including a first peripheral portion and a first conductive unit formed at the first peripheral portion, and a second pouch case including a second peripheral portion and a second conductive unit formed at the second peripheral portion, the second pouch case being sealed with the first pouch case, and an electrode assembly accommodated in the pouch. The first conductive unit and the second conductive unit are in contact with each other to form an electric circuit along the first peripheral portion or the second peripheral portion.

Abstract: A lithium secondary battery according to embodiments of the disclosed technology includes a pouch and an electrode assembly accommodated in the pouch. The pouch includes a first pouch case including a first peripheral portion and a first magnetic unit formed at the first peripheral portion, and a second pouch case including a second peripheral portion and a second magnetic unit formed at the second peripheral portion. The second magnetic unit has an opposite polarity from that of the first magnetic unit, and the second pouch case is sealed with the first pouch case.

Abstract: A secondary battery includes an electrode assembly; an electrode lead structure including an electrode lead bonded to an electrode tab of the electrode assembly and a molded portion surrounding the electrode lead; and a spacer inserted into a space between the electrode lead structure and the electrode assembly. By removing a corner portion stress caused by forming and a stress from folding a pouch in a secondary battery assembly process including pouch forming, it is possible to minimize damage to the pouch and secure battery stability. In addition, by providing a secondary battery structure having a novel structure, it is possible to increase energy density by eliminating pouch cell thickness limitation due to pouch forming.

Abstract: A pouch for a secondary battery having improved stability to an external force and an internal pressure and a secondary battery including the pouch are disclosed. In an aspect, a pouch for a secondary battery implemented based on some embodiments of the disclosed technology includes a pouch cup including a battery cell accommodating portion, a tab receiving portion formed at one end portion of the pouch cup to be in communication with one end of the battery cell accommodating portion, a supporting portion adjacent to the tab receiving portion at the one end portion of the pouch cup to be separated from the battery cell accommodating portion and the tab receiving portion, the supporting portion comprising a plurality of columns in the supporting portion, and a reinforcing film attached on an outer wall of the supporting portion, the reinforcing film including a material different from that of the outer wall of the supporting portion.

Abstract: A pouch for a secondary battery having improved stability to an external force and an internal pressure and a secondary battery including the pouch are disclosed. In an aspect, a pouch for a secondary battery implemented based on some embodiments of the disclosed technology includes a pouch cup including a battery cell accommodating portion, a tab receiving portion formed at one end portion of the pouch cup to be in communication with one end of the battery cell accommodating portion, and a supporting portion adjacent to the tab receiving portion at the one end portion of the pouch cup. The supporting portion includes a space separated from the battery cell accommodating portion and the tab receiving portion.

Abstract: A battery pack including heterogeneous secondary batteries includes: a first battery set in which a plurality of first secondary batteries are stacked; and a second battery set in which a plurality of second secondary batteries are stacked, in which each of the first battery set and the second battery set is formed of a plurality, and the battery pack has an arrangement structure in which the plurality of first battery sets and the plurality of second battery sets are alternately stacked in one direction.