Secondary battery and device containing the same

Abstract

The present application provides a secondary battery and a device containing the secondary battery, wherein the secondary battery comprises a negative electrode plate, a negative electrode current collector and a negative electrode film disposed on at least one surface of the negative electrode current collector and comprising a negative electrode active material; an electrolyte, comprising an electrolyte salt, an organic solvent and an additive; the negative electrode active material comprises a silicon-based material; the additive comprises an additive A and an additive B; the additive A is selected from one or more of the compounds shown in Formula 1; the additive B is selected from one or more of the compounds described in Formula 2; the melting point of the additive B is less than or equal to 5°C. The secondary battery of the present application and the device containing the secondary battery can simultaneously take into account good high-temperature cycle performance, high-temperature storage performance and low-temperature discharge performance. #imgabs0#NC——R2——CNFormula 2.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a secondary battery and a device containing the secondary battery. Background Art

[0002] In the rapidly developing information age, people's demand for electronic products such as mobile phones, notebooks, and cameras is increasing year by year. As the working power source of electronic products, secondary batteries with high energy density, no memory effect, and high working voltage are gradually replacing traditional Ni-Cd and MH-Ni batteries. However, with the expansion of market demand for electronic products and the development of power and energy storage equipment, people's requirements for secondary batteries are constantly increasing, and the development of secondary batteries with high energy density has become a top priority. Using high-specific-capacity silicon-based materials as the negative active material of secondary batteries can effectively improve the energy density of secondary batteries, but the electrochemical performance of batteries using silicon-based materials is often poor.

[0003] Therefore, there is an urgent need to develop a secondary battery with high energy density and good electrochemical performance. Summary of the invention

[0004] In view of the problems existing in the background technology, the purpose of the present application is to provide a secondary battery and a device containing the secondary battery, wherein the secondary battery can simultaneously take into account good high-temperature cycle performance, high-temperature storage performance and low-temperature discharge performance.

[0005] In order to achieve the above-mentioned object, in one aspect of the present application, a secondary battery is provided, comprising: a negative electrode plate, comprising a negative electrode current collector and a negative electrode film disposed on at least one surface of the negative electrode current collector and comprising a negative electrode active material; an electrolyte, comprising an electrolyte salt, an organic solvent and an additive; wherein the negative electrode active material comprises a silicon-based material; the additive comprises an additive A and an additive B; the additive A is selected from one or more of the compounds shown in Formula 1;

[0006]

[0007] Wherein, R1 is one or more selected from C2-C4 alkylene, C2-C4 halogenated alkylene, C2-C4 alkenylene, C2-C4 halogenated alkenylene, C6-C18 arylene, C6-C18 halogenated arylene;

[0008] The additive B is selected from one or more of the compounds described in Formula 2;

[0009] NC-R2-CN type 2

[0010] Wherein, R2 is selected from one or more of C1-C20 alkylene, C1-C20 halogenated alkylene, C1-C20 alkyleneoxy, C1-C20 halogenated alkyleneoxy, C1-C20 alkenylene, and C1-C20 halogenated alkenylene;

[0011] The melting point of the additive B is less than or equal to 5°C.

[0012] In the secondary battery of the present application, the negative electrode plate includes a silicon-based material, and the electrolyte includes additive A and additive B at the same time, and the melting point of additive B is less than or equal to 5°C. Under their combined effect, the secondary battery can simultaneously have good high-temperature cycle performance, high-temperature storage performance and low-temperature discharge performance.

[0013] In any embodiment of the first aspect of the present application, the additive A is selected from one or more of the following compounds;

[0014]

[0015] In any embodiment of the first aspect of the present application, the additive B is selected from one or more of adiponitrile, glutaronitrile, 2-methylglutaronitrile, 1,2-bis(2-cyanoethoxy)ethane, and 1,4-bis(2-cyanoethoxy)butane. Optionally, the additive B is selected from one or more of adiponitrile and 1,2-bis(2-cyanoethoxy)ethane.

[0016] In any embodiment of the first aspect of the present application, the mass proportion of additive A in the electrolyte is ≤2%. If the content of additive A is too high, it will increase the film formation resistance on the negative electrode surface and deteriorate the low temperature performance of the secondary battery. Optionally, the mass proportion of additive A in the electrolyte is 0.1% to 1%.

[0017] In any embodiment of the first aspect of the present application, the mass proportion of additive B in the electrolyte is ≤5%. If the content of additive B is too high, too much additive B will inevitably form a film on the surface of the negative electrode, thereby deteriorating the high temperature cycle performance of the secondary battery. Optionally, the mass proportion of additive B in the electrolyte is 0.5% to 3%.

[0018] In any embodiment of the first aspect of the present application, the additive further comprises one or more of vinylene carbonate VC, fluoroethylene carbonate FEC, vinyl sulfate DTD, 1,3-propane sultone PS, and 1,3-propenyl-sultone PST.

[0019] In any embodiment of the first aspect of the present application, the secondary battery further comprises a positive electrode plate, the positive electrode plate comprises a positive electrode current collector and a positive electrode film disposed on at least one surface of the positive electrode current collector and comprising a positive electrode active material; the positive electrode active material comprises one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and transition metal phosphate. Optionally, the positive electrode active material comprises lithium cobalt oxide. When the positive electrode active material comprises lithium cobalt oxide, the electrolyte of the present application has a more obvious effect on improving battery performance.

[0020] In any embodiment of the first aspect of the present application, the silicon-based material includes one or more of elemental silicon, silicon-oxygen compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. Optionally, the silicon-based material includes silicon-oxygen compounds.

[0021] In any embodiment of the first aspect of the present application, the negative electrode active material further comprises a carbon material, and the carbon material is selected from one or more of artificial graphite, natural graphite, soft carbon, and hard carbon. Optionally, the carbon material is selected from one or more of artificial graphite and natural graphite.

[0022] In a second aspect of the present application, a device is provided, which includes the secondary battery described in the first aspect of the present application.

[0023] The device of the present application includes the secondary battery, and thus has at least the same advantages as the secondary battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of one embodiment of a secondary battery.

[0025] Figure 2 is a schematic diagram of an embodiment of a battery module.

[0026] Figure 3 is a schematic diagram of one embodiment of a battery pack.

[0027] Figure 4 yes Figure 3 Exploded diagram of .

[0028] Figure 5 It is a schematic diagram of one embodiment of a device in which a secondary battery is used as a power source.

[0029] The reference numerals are described as follows:

[0030] 1 battery pack

[0031] 2 upper box

[0032] 3 lower cabinets

[0033] 4 battery modules

[0034] 5. Secondary battery DETAILED DESCRIPTION

[0035] The secondary battery according to the present application and a device including the secondary battery are described in detail below.

[0036] First, a secondary battery according to the first aspect of the present application will be described.

[0037] According to the first aspect of the present application, the secondary battery comprises a negative electrode plate and an electrolyte; the negative electrode plate comprises a negative electrode current collector and a negative electrode film disposed on at least one surface of the negative electrode current collector and comprising a negative electrode active material, wherein the negative electrode active material comprises a silicon-based material; the electrolyte comprises an electrolyte salt, an organic solvent and an additive. The additive comprises an additive A and an additive B, wherein the additive A is selected from one or more of the compounds shown in Formula 1,

[0038]

[0039] Wherein, R1 is selected from one or more of C2-C4 alkylene, C2-C4 halogenated alkylene, C2-C4 alkenylene, C2-C4 halogenated alkenylene, C6-C18 arylene, C6-C18 halogenated arylene; the additive B is selected from one or more of the compounds described in Formula 2,

[0040] NC-R2-CN type 2

[0041] Among them, R2 is selected from one or more of C1-C20 alkylene, C1-C20 halogenated alkylene, C1-C20 alkyleneoxy, C1-C20 halogenated alkyleneoxy, C1-C20 alkenylene, and C1-C20 halogenated alkenylene; and the melting point of the additive B is less than or equal to 5°C.

[0042] Optionally, the halogenated element can be selected from one or more of F, Cl, Br, and I.

[0043] The inventors found that the additive shown in Formula 1 can form a dense and uniform passivation film on the surface of the silicon-based material, which can effectively prevent the direct contact between the electrolyte solvent and the silicon-based material, reduce the side reaction of the electrolyte solvent on the negative electrode surface, and thus reduce the gas production of the secondary battery, and improve the high-temperature storage performance of the secondary battery. However, the film formation impedance of the passivation film formed by the additive shown in Formula 1 on the negative electrode surface is large, which affects the cycle performance of the battery. Through a large number of studies, the inventors found that when the electrolyte also includes additive B, the film formation impedance of the negative electrode surface can be reduced, effectively improving the low-temperature discharge performance of the secondary battery.

[0044] In the secondary battery according to the first aspect of the present application, optionally, the additive A is selected from one or more of the following compounds.

[0045]

[0046] In the secondary battery according to the first aspect of the present application, optionally, the additive B is selected from one or more of adiponitrile, glutaronitrile, 2-methylglutaronitrile, 1,2-bis(2-cyanoethoxy)ethane, and 1,4-bis(2-cyanoethoxy)butane; more optionally, the additive B is selected from one or more of adiponitrile and 1,2-bis(2-cyanoethoxy)ethane.

[0047] In the secondary battery according to the first aspect of the present application, optionally, the mass proportion of the additive A in the electrolyte is ≤2%. If the content of the additive A is too high, it will increase the film formation resistance on the negative electrode surface and deteriorate the low temperature performance of the secondary battery. Optionally, the mass proportion of the additive A in the electrolyte is 0.1% to 1%.

[0048] In the secondary battery according to the first aspect of the present application, optionally, the mass proportion of the additive B in the electrolyte is ≤5%. If the content of additive B is too high, too much additive B will inevitably form a film on the surface of the negative electrode, thereby deteriorating the high temperature cycle performance of the secondary battery. Optionally, the content of the additive B is 0.5% to 3% of the total weight of the electrolyte.

[0049] In the secondary battery according to the first aspect of the present application, the additive may also include one or more of vinylene carbonate (VC), fluoroethylene carbonate (FEC), diethyl sulfate (DTD), 1,3-propane sultone (PS), and 1,3-propenyl sultone (PST).

[0050] In the secondary battery according to the first aspect of the present application, the type of the organic solvent is not particularly limited and can be selected according to actual needs. Specifically, the organic solvent can be selected from one or more of chain esters and cyclic esters. Optionally, the chain ester can be selected from one or more of dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, methyl propyl carbonate, methyl formate, ethyl formate, methyl acetate, ethyl acetate, propyl propionate, ethyl butyrate, ethyl propionate, and propyl butyrate; the cyclic ester can be selected from one or more of ethylene carbonate, propylene carbonate, butylene carbonate, γ-butyrolactone, and tetrahydrofuran.

[0051] In the secondary battery according to the first aspect of the present application, the type of the electrolyte salt is not particularly limited and can be selected according to actual needs. Specifically, the electrolyte salt can be selected from one or more of LiPF6, LiBF4, LiFSI, LiTFSI, LiClO4, LiAsF6, LiBOB, LiDFOB, LiPO2F2, LiTFOP, LiN(SO2RF)2, LiN(SO2F)(SO2RF), wherein RF=C n F 2n+1 , represents a saturated perfluoroalkyl group, and n is an integer within the range of 1 to 10.

[0052] In the secondary battery according to the first aspect of the present application, the content of the electrolyte salt is not particularly limited and can be selected according to actual needs. Optionally, the content of the electrolyte salt is 6% to 25% of the total weight of the electrolyte; more optionally, the content of the electrolyte salt is 6% to 20% of the total weight of the electrolyte.

[0053] In the secondary battery according to the first aspect of the present application, the secondary battery further comprises a positive electrode sheet, the positive electrode sheet comprising a positive current collector and a positive electrode film disposed on at least one surface of the positive current collector and comprising a positive electrode active material. Optionally, the positive electrode active material comprises one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, transition metal phosphate, etc.; more optionally, the positive electrode active material comprises lithium cobalt oxide (e.g., lithium cobaltate). When the positive electrode active material comprises lithium cobalt oxide, the electrolyte of the present application has a more obvious effect on improving battery performance.

[0054] In the secondary battery according to the first aspect of the present application, the type of the positive electrode current collector is not particularly limited and can be selected according to specific needs. Specifically, the positive electrode current collector can be selected from metal foil, for example, the positive electrode current collector can be selected from aluminum foil.

[0055] In the secondary battery according to the first aspect of the present application, the type of the negative electrode current collector is not particularly limited and can be selected according to specific needs. Specifically, the negative electrode current collector can be selected from metal foil, for example, the positive electrode current collector can be selected from copper foil.

[0056] In the secondary battery according to the first aspect of the present application, optionally, the silicon-based material includes one or more of elemental silicon, silicon-oxygen compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys; more optionally, the silicon-based material includes silicon-oxygen compounds.

[0057] In the secondary battery according to the first aspect of the present application, optionally, the negative electrode active material also includes one or more of natural graphite, artificial graphite, soft carbon, and hard carbon; more optionally, the negative electrode active material also includes one or more of natural graphite and artificial graphite.

[0058] In the secondary battery according to the first aspect of the present application, the secondary battery further comprises a separator. The type of the separator is not particularly limited, and it can be any separator suitable for secondary batteries in the art. Specifically, the separator can be selected from one or more of a polyethylene film, a polypropylene film, a polyvinylidene fluoride film, and a multilayer composite film thereof.

[0059] In some embodiments, the secondary battery may include an outer package for packaging the positive electrode sheet, the negative electrode sheet and the electrolyte. As an example, the positive electrode sheet, the negative electrode sheet and the separator may be laminated or wound to form an electrode assembly of a laminate structure or an electrode assembly of a wound structure, and the electrode assembly is packaged in the outer package; the electrolyte is infiltrated in the electrode assembly. The number of electrode assemblies in the secondary battery may be one or more, which can be adjusted according to demand.

[0060] In some embodiments, the outer packaging of the secondary battery may be a soft package, such as a bag-type soft package. The material of the soft package may be plastic, such as one or more of polypropylene PP, polybutylene terephthalate PBT, polybutylene succinate PBS, etc. The outer packaging of the secondary battery may also be a hard shell, such as an aluminum shell, etc.

[0061] The present application has no particular limitation on the shape of the secondary battery, which may be cylindrical, square or any other shape. Figure 1 The secondary battery 5 is a square structure as an example.

[0062] In some embodiments, secondary batteries may be assembled into a battery module. The battery module may contain multiple secondary batteries, and the specific number may be adjusted according to the application and capacity of the battery module.

[0063] Figure 2 4 is an example of a battery module. Figure 2 In the battery module 4, the plurality of secondary batteries 5 may be arranged in sequence along the length direction of the battery module 4. Of course, they may also be arranged in any other manner. Further, the plurality of secondary batteries 5 may be fixed by fasteners.

[0064] Optionally, the battery module 4 may further include a housing having a housing space, and the plurality of secondary batteries 5 are housed in the housing space.

[0065] In some embodiments, the battery modules described above may also be assembled into a battery pack, and the number of battery modules contained in the battery pack may be adjusted according to the application and capacity of the battery pack.

[0066] Figure 3 and Figure 4 1 is a battery pack 1 as an example. Figure 3 and Figure 4 The battery pack 1 may include a battery box and a plurality of battery modules 4 disposed in the battery box. The battery box includes an upper box body 2 and a lower box body 3. The upper box body 2 can cover the lower box body 3 and form a closed space for accommodating the battery modules 4. The plurality of battery modules 4 can be arranged in the battery box in any manner.

[0067] Next, the device according to the second aspect of the present application is described.

[0068] The device according to the second aspect of the present application includes the secondary battery according to the first aspect of the present application, and the secondary battery can be used as a power source for the device, or as an energy storage unit for the device. Optionally, the device includes but is not limited to mobile devices (such as mobile phones, laptops, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships and satellites, energy storage systems, etc.

[0069] The device can select a secondary battery, a battery module or a battery pack according to its usage requirements.

[0070] Figure 5 The device is used as an example. The device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle. In order to meet the device's requirements for high power and high energy density of secondary batteries, a battery pack or a battery module can be used.

[0071] Another example of a device may be a mobile phone, a tablet computer, a notebook computer, etc. Such a device is usually required to be thin and light, and a secondary battery may be used as a power source.

[0072] The present application is further described below in conjunction with the examples. It should be understood that these examples are only used to illustrate the present application and are not used to limit the scope of the present application.

[0073] The secondary batteries of Examples 1-17 and Comparative Examples 1-4 were prepared according to the following method:

[0074] (1) Preparation of positive electrode sheet

[0075] The positive electrode active material lithium cobalt oxide (LiCoO2), the binder polyvinylidene fluoride, and the conductive agent Super P are mixed in a weight ratio of 98:1:1, and N-methylpyrrolidone (NMP) is added. The mixture is stirred under the action of a vacuum mixer until the system becomes uniform and transparent to obtain a positive electrode slurry; the positive electrode slurry is then evenly coated on the positive electrode current collector aluminum foil; the aluminum foil is dried at room temperature and then transferred to an oven for drying, and then cold pressed and cut to obtain a positive electrode sheet

[0076] (2) Preparation of negative electrode sheet

[0077] The negative electrode active material (silicon dioxide: artificial graphite = 1:9) is mixed, and then mixed with the conductive agent Super P and the binder acrylate in a mass ratio of 92:2:6, deionized water is added, and the negative electrode slurry is obtained under the action of a vacuum mixer; the negative electrode slurry is evenly coated on the negative electrode current collector copper foil; the copper foil is dried at room temperature and then transferred to an oven for drying, and then cold pressed and cut to obtain the negative electrode sheet.

[0078] (3) Preparation of electrolyte

[0079] In an argon atmosphere glove box with a water content of <10ppm, ethylene carbonate (EC), propylene carbonate (PC) and diethyl carbonate (DEC) are mixed in a weight ratio of EC:PC:DEC=1:1:1 to obtain a non-aqueous organic solvent, and then the fully dried electrolyte salt LiPF6 is dissolved in the non-aqueous organic solvent, and then the additive FEC is added to the non-aqueous organic solvent, and the electrolyte is obtained after mixing evenly. Among them, the content of LiPF6 is 12.5% ​​of the total weight of the electrolyte. The type, characteristic parameters and content of the additives are shown in Table 1. In Table 1, the content of the additive is the weight percentage calculated based on the total weight of the electrolyte.

[0080] (4) Preparation of isolation membrane

[0081] A polyethylene film is used as the isolation film.

[0082] (5) Preparation of secondary batteries

[0083] The positive electrode sheet, the separator, and the negative electrode sheet are stacked in order, so that the separator is placed between the positive and negative electrode sheets to play an isolating role, and then they are wound to obtain an electrode assembly; the electrode assembly is placed in an outer package, and the prepared electrolyte is injected into the dried battery. After vacuum packaging, standing, formation, shaping and other processes, a secondary battery is obtained.

[0084] Table 1 Parameters of Examples 1-17 and Comparative Examples 1-4

[0085]

[0086] Next, the test process of the secondary battery is described.

[0087] (1) High temperature storage performance test of secondary batteries

[0088] At 60°C, the secondary battery is charged at a constant current of 0.5C to 4.3V, and then charged at a constant voltage of 4.3V to a current of 0.05C. The volume of the secondary battery at this time is tested by the drainage method and recorded as V1. The secondary battery is then placed in a constant temperature box at 60°C, taken out after storage for 30 days, and the volume of the secondary battery at this time is tested and recorded as V2.

[0089] The volume expansion ratio (%) of the secondary battery after storage at 60° C. for 30 days=[(V2−V1) / V1]×100%.

[0090] (2) High temperature cycle performance test of secondary batteries

[0091] At 45°C, charge the secondary battery at a constant current of 1C to 4.3V, then charge at a constant voltage of 4.3V to a current of 0.05C, let it stand for 5 minutes, and then discharge at a constant current of 1C to 2.8V. This is the first charge and discharge cycle of the secondary battery. The discharge capacity is recorded as the discharge capacity of the first cycle of the secondary battery. The secondary battery is charged and discharged for 800 cycles according to the above method, and the discharge capacity of the secondary battery after 800 cycles is recorded.

[0092] Capacity retention rate (%) of the secondary battery after 800 cycles at 45° C.=(discharge capacity of the secondary battery after 800 cycles / discharge capacity of the secondary battery at the first cycle)×100%.

[0093] (3) Secondary battery low temperature discharge performance test

[0094] At 25°C, the secondary battery was charged at a constant current of 1C (nominal capacity) to 4.3V, then charged at a constant voltage of 4.3V to a current of 0.05C, allowed to stand for 5 minutes, and then discharged at a constant current of 1C to a cut-off voltage of 2.8V. The actual discharge capacity of the secondary battery at this time was tested and recorded as d0.

[0095] At 25°C, the secondary battery was charged at a constant current of 1C (nominal capacity) to 4.3V, then charged at a constant voltage to a current of 0.05C, left for 5 minutes, and then left at -10°C for more than 4 hours to make the temperature of the secondary battery reach -10°C, and then discharged at a constant current of 0.5C to a cut-off voltage of 2.8V. The actual discharge capacity of the secondary battery at this time was tested and recorded as d1.

[0096] Discharge capacity retention rate of the secondary battery at -10°C (%) = (discharge capacity d1 at -10°C / discharge capacity d0 at 25°C) x 100%.

[0097] Table 2 Performance test results of Examples 1-17 and Comparative Examples 1-4

[0098]

[0099] From the analysis of the test results in Table 2, it can be seen that the secondary batteries of Examples 1-17 of the present application use silicon-based materials as negative electrode active materials, and additive A and additive B with a melting point less than or equal to 5°C are added to the electrolyte. Under their joint action, the secondary batteries of the present application simultaneously take into account good high-temperature cycle performance, high-temperature storage performance and low-temperature discharge performance.

[0100] In Comparative Example 1, the electrolyte solution was not added with additive B, and the obtained secondary battery had poor high-temperature cycle performance and low-temperature discharge performance.

[0101] In Comparative Example 2, additive A was not added to the electrolyte, and the obtained secondary battery had poor high-temperature cycle performance and low-temperature discharge performance, and the high-temperature storage performance of the secondary battery deteriorated.

[0102] Although the additive B added to the electrolyte in Comparative Example 3 satisfies Formula 2, its melting point is higher than 5° C., and the low-temperature discharge performance of the obtained secondary battery is deteriorated.

[0103] The additive B added to the electrolyte in Comparative Example 4 does not satisfy Formula 2, and the high-temperature cycle and low-temperature discharge performances of the obtained secondary battery are deteriorated.

Claims

1. A secondary battery comprising: A negative electrode sheet, comprising a negative electrode current collector and a negative electrode membrane sheet disposed on at least one surface of the negative electrode current collector and comprising a negative electrode active material; Electrolyte, including electrolyte salt, organic solvent and additives; in, The negative electrode active material includes a silicon-based material and a carbon material, wherein the carbon material is selected from one or more of artificial graphite, natural graphite, soft carbon, and hard carbon; The additives include additive A and additive B; The additive A is selected from compound 1-1, Compound 1-1; The melting point of the additive B is less than or equal to 5°C; and the additive B is selected from 1,2-bis(2-cyanoethoxy)ethane, The mass proportion of the additive A in the electrolyte is 0.5% to 1%, and the mass proportion of the additive B in the electrolyte is 0.5% to 3%.

2. The secondary battery according to claim 1, wherein The additives also include one or more of vinylene carbonate VC, fluoroethylene carbonate FEC, vinyl sulfate DTD, 1,3-propane sultone PS, and 1,3-propenyl-sultone PST.

3. The secondary battery according to claim 1, wherein The secondary battery also includes a positive electrode plate, which includes a positive electrode collector and a positive electrode membrane arranged on at least one surface of the positive electrode collector and including a positive electrode active material; the positive electrode active material includes one or more of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and transition metal phosphates.

4. The secondary battery according to claim 3, wherein The positive electrode active material includes lithium cobalt oxide.

5. The secondary battery according to claim 1, wherein The silicon-based material includes one or more of elemental silicon, silicon-oxygen compounds, silicon-carbon compounds, silicon-nitrogen compounds, and silicon alloys.

6. The secondary battery according to claim 5, wherein The silicon-based material includes a silicon-oxygen compound.

7. The secondary battery according to claim 1, wherein The carbon material is selected from one or more of artificial graphite and natural graphite.

8. An electrical device comprising the secondary battery according to any one of claims 1 to 7.

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