Provided is a positive electrode for a secondary battery, which has a multi-layer structure including a first positive electrode active material layer and a second positive electrode active material layer, wherein the first positive electrode active material layer includes a first lithium composite transition metal oxide containing nickel, cobalt, and manganese, the second positive electrode active material layer includes a second lithium composite transition metal oxide containing nickel, cobalt, and manganese, the first lithium composite transition metal oxide and the second lithium composite transition metal oxide have mutually different nickel contents, wherein the positive electrode active material layer including a lithium composite transition metal oxide having a relatively high nickel content includes an electrolyte additive, and the positive electrode active material layer including a lithium composite transition metal oxide having a relatively low nickel content does not include an electrolyte additive.

Provided is a positive electrode for a secondary battery, which has a multi-layer structure including a first positive electrode active material layer and a second positive electrode active material layer, wherein the first positive electrode active material layer includes a first lithium composite transition metal oxide containing nickel, cobalt, and manganese, the second positive electrode active material layer includes a second lithium composite transition metal oxide containing nickel, cobalt, and manganese, the first lithium composite transition metal oxide and the second lithium composite transition metal oxide have mutually different nickel contents, wherein the positive electrode active material layer including a lithium composite transition metal oxide having a relatively high nickel content includes an electrolyte additive, and the positive electrode active material layer including a lithium composite transition metal oxide having a relatively low nickel content does not include an electrolyte additive.

Various embodiments provide an electrolyte solution, a secondary battery, a battery module, a battery pack and an electric device. In those embodiments, the electrolyte solution includes an electrolyte, a solvent and an additive, the additive including sodium hydrosulfite. Various embodiments improve an overall performance of the secondary battery, for example, initial DCR, storage gas production, a rate performance, or the like.

Various embodiments provide an electrolyte solution, a secondary battery, a battery module, a battery pack and an electric device. In those embodiments, the electrolyte solution includes an electrolyte, a solvent and an additive, the additive including sodium hydrosulfite. Various embodiments improve an overall performance of the secondary battery, for example, initial DCR, storage gas production, a rate performance, or the like.

The present invention relates to a non-aqueous electrolyte for a lithium secondary battery and a lithium secondary battery comprising the same, the non-aqueous electrolyte comprising a non-aqueous organic solvent, a lithium salt, a first additive including at least one of compounds represented by chemical formulas 1 to 4, and a second additive comprising a cyclic sulfide-based compound, wherein the mixing ratio of the first additive and the second additive is a weight ratio of 0.2:1 to 10:1.

The present invention relates to a non-aqueous electrolyte for a lithium secondary battery and a lithium secondary battery comprising the same, the non-aqueous electrolyte comprising a non-aqueous organic solvent, a lithium salt, a first additive including at least one of compounds represented by chemical formulas 1 to 4, and a second additive comprising a cyclic sulfide-based compound, wherein the mixing ratio of the first additive and the second additive is a weight ratio of 0.2:1 to 10:1.

An electrolyte for a lithium-secondary battery including a solvent, a lithium salt and an additive, wherein the additive includes a diamine-based compound, and a lithium-secondary battery including the same.

An electrolyte for a lithium-secondary battery including a solvent, a lithium salt and an additive, wherein the additive includes a diamine-based compound, and a lithium-secondary battery including the same.

Provided are a bissulfonate compound, a preparation method therefor, an electrolytic solution and an energy storage device. The bissulfonate compound has a structure of (I) and is applied as an additive to an energy storage device, so that a stable SEI film can be formed on a surface of an anode of the energy storage device, and the decomposition of a solvent in the electrolytic solution can be suppressed. As the stable SEI film can be formed on the surface of the anode, lithium ions can be smoothly embedded and disembedded at a low temperature, thereby improving the low-temperature performance of the energy storage device. Furthermore, a sulfonate group in the bissulfonate compound can coordinate with transition metal ions to form a complex, so that the surface of the positive electrode is passivated, the dissolution of the metal ions of the positive electrode is suppressed, and the decomposition effect of the solvent by an active substance in a high oxidation state is reduced, thereby improving the electrochemical performance of the energy storage device under a high temperature condition. In an energy storage device, the bissulfonate compound can inhibit the increase of the direct current internal resistance, and improve the high temperature performance and the low-temperature performance of the energy storage device.

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Provided are a bissulfonate compound, a preparation method therefor, an electrolytic solution and an energy storage device. The bissulfonate compound has a structure of (I) and is applied as an additive to an energy storage device, so that a stable SEI film can be formed on a surface of an anode of the energy storage device, and the decomposition of a solvent in the electrolytic solution can be suppressed. As the stable SEI film can be formed on the surface of the anode, lithium ions can be smoothly embedded and disembedded at a low temperature, thereby improving the low-temperature performance of the energy storage device. Furthermore, a sulfonate group in the bissulfonate compound can coordinate with transition metal ions to form a complex, so that the surface of the positive electrode is passivated, the dissolution of the metal ions of the positive electrode is suppressed, and the decomposition effect of the solvent by an active substance in a high oxidation state is reduced, thereby improving the electrochemical performance of the energy storage device under a high temperature condition. In an energy storage device, the bissulfonate compound can inhibit the increase of the direct current internal resistance, and improve the high temperature performance and the low-temperature performance of the energy storage device.

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