Battery

Abstract

A battery comprising a negative electrode plate and an electrolyte solution; The negative electrode plate includes a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector; the negative electrode active material layer includes a negative electrode active material comprising a silicon-based material; and wherein, based on a total weight of the negative electrode active material layer, a proportion of silicon A is in a unit of %; a surface of the negative electrode active material layer has recesses having a depth B in a unit of µm, a width C in a unit of µm and a pitch D in a unit of mm; the electrolyte solution comprises 1,3-propenesultone and is a mass percent of 1,3-propenesultone in a total mass of the electrolyte solution E in a unit of %; and where the relationship 0.05 ≤ C / (A×E×B×D) ≤ 100 is satisfied.

Description

TECHNICAL FIELDThe present disclosure relates to the field of batteries, and more particularly to a battery.BACKGROUNDIn recent years, lithium ion batteries have been widely used in, for example, digital products, energy stores, power supply, military aerospace, and communication equipment. Further, as electronic equipment is diversified and its functions are developed, human demands on the life of the batteries of electronic equipment are becoming higher and higher. Therefore, improving the energy density of lithium ion batteries is a current focus of research. The use of silicon-containing materials as the negative electrode active material layer is one of the most effective means for improving the energy density of lithium ion batteries. However, as the silicon content in the negative electrode active material layer increases, the problem of damage and corner cracking of the outer foil shell becomes more and more severe in the later phases of the battery cycle, which directly affects the service life of the batteries.Therefore, it is of great importance to improve the energy density of lithium ion batteries and at the same time to solve the problem of damage and cracking of the outer foil shell in the later phase of the battery cycle.SUMMARYThe present disclosure provides a battery to overcome the problem of the prior art in which high energy density silicon-doped batteries are susceptible to damage and corner cracks to the outer foil shell during the later phases of the battery cycle. The battery of the present disclosure not only has high energy density, but also substantially alleviates the problem of damage and corner cracks of the outer foil shell in the later phases of the battery cycle.The present disclosure provides a battery including a negative electrode plate and an electrolyte solution. The negative electrode plate includes a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector. The negative electrode active material layer includes a negative electrode active material layer including a silicon-based material. Based on a total weight of the negative electrode active material layer, a content of silicon is A (unit: %). The surface of the negative electrode active material layer has recesses having a depth of B (unit: μm), a width of C (unit: μm), and a pitch of D (unit: mm). The electrolyte solution includes 1,3-propene sultone, and a mass percentage of 1,3-propene sultone in a total mass of the electrolyte solution is E (unit: %). The relationship 0.05≤C / (A×E×B×D)≤100 is satisfied.By the above technical solution, the present disclosure provides the following advantages over the related art:(1) The battery of the present disclosure has high energy density while mitigating the problem of damage and corner cracks of the outer foil shell in the later phases of the battery cycle, and has excellent sealing performance after the cycle.(2) The battery of the present disclosure has superior cycle performance, high storage performance at high temperatures and high humidity, and low temperature upon discharge.The endpoints and all values included in the ranges disclosed herein are not limited to the exact ranges or values and should be interpreted to include values that approximate these ranges or values. In numerical ranges, the endpoints of the ranges, the endpoints, and single point values and single point values may be combined to form one or more new numerical ranges that should be considered specifically disclosed herein.BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a schematic cross-sectional diagram of a negative electrode plate according to an embodiment of the present disclosure. FIG. 2 is a scanning electron microscope (SEM) photograph of a negative electrode plate according to an embodiment of the present disclosure. FIG. 3 are schematic diagrams of a width of a groove according to an embodiment of the present disclosure. FIG. 4 are schematic diagrams of a pitch of two grooves according to an embodiment of the present disclosure.DETAILED DESCRIPTIONS OF THE EMBODIMENTSHereinafter, detailed explanation will be given of the specific embodiments of the present disclosure. It should be understood that the specific embodiments described herein are intended to illustrate and explain the disclosure, and not to limit it.Conventional silicon-containing batteries often suffer from the problem of damage and cracking to the corners of the outer foil shell during the later phases of the battery cycle. Through extensive experiments, the present inventors have found that the possible causes of the above problems are as follows: 1. when the silicon-containing batteries undergo charge / discharge cycles, the volume expansion of the silicon becomes larger and larger, thereby ultimately breaking the outer foil shell. 2. during the process of lithium deintercalation / intercalation in the negative electrode plate, the probability of side reactions between the negative electrode plate and the electrolyte solution increases, which leads to an increased gas development and a subsequent breakage of the outer foil shell. 3. on the one hand, the volume expansion of the silicon exerts a certain pressure on the negative electrode current collector. On the other hand, the corrosion of the negative electrode current collector by the electrolyte solution damages its crystal structure, thereby becoming thinner and more stretchable. Both factors cause the negative electrode current collector to extend, piercing the outer foil shell.Based on the above three reasons, the inventors conducted a great number of targeted studies and found that modification of either the electrolyte solution or the structure of the negative electrode plate can partially alleviate the above problems. This is because the electrolyte solution as an important component of the battery facilitates the transportation of Li + and the additives contained therein form a protective film on the negative electrode plate, which can inhibit the volume expansion of the negative electrode plate and protect the negative electrode plate. Also, structural modifications of the negative electrode plate as an important component of the battery can reduce the expansion thereof.On the basis of this, the present inventors propose the following solution:The present disclosure provides a battery. The battery may include a negative electrode plate and an electrolyte solution. The negative electrode plate may include a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector. The negative electrode active material layer may include a negative electrode active material layer, and the negative electrode active material layer may include a silicon-based material. Based on a total weight of the negative electrode active material layer, a proportion of silicon is A (unit: %). A surface of the negative electrode active material layer may have recesses. FIG. 1 is a schematic cross-sectional view of a negative electrode plate according to an embodiment of the present disclosure. As illustrated, the negative electrode plate includes a negative electrode current collector 1 and negative electrode active material layers 2 disposed on both surfaces of the negative electrode current collector 1, and the surfaces of the negative electrode active material layers 2 include recesses 3. FIG. 2 shows a scanning electron microscope photograph (SEM) of a negative electrode plate according to an embodiment illustrating the recesses on the surface of the negative electrode active material layer.The depth of the recesses may be B (unit: μm), the width of the recesses may be C (unit: μm), and the pitch of the recesses may be D (unit: mm). The electrolyte solution may include 1,3-propene sultone (PST), and a mass percentage of 1,3-propene sultone in a total mass of the electrolyte solution is E (unit: %). A, B, C, D, and E satisfy: 0.05≤C / (A×E×B×D)≤100, for example, 0.05, 0.1, 0.5, 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100.The recesses on the surface of the negative electrode plate improve wettability of the electrolyte solution in the negative electrode active material layer, thereby improving capacity utilization and energy density. Moreover, the recesses provide buffer space for the volume expansion of the silicon-based material. PST in the electrolytic solution forms a stable protective film on the negative electrode. This protective film can not only inhibit the volume expansion of the silicon-based material to some extent, but also protect the negative electrode plate. This protection is reflected in two aspects: on the one hand, it can reduce the possibility of side reactions between the electrolyte solution and the negative electrode active material layer; on the other hand, it can reduce the corrosion of the negative electrode current collector by the electrolyte solution, thereby reducing the dissolution of metal ions (for example, copper ions) from the negative electrode current collector and inhibiting the expansion of the negative electrode current collector during the battery cycle. However, the use of a negative electrode plate with depressions or an electrolyte solution containing PST alone is not sufficient to effectively prevent damage and cracks in the corners of the outer foil shell in the later phases of the battery cycle. The combination of a negative electrode plate with recesses and an electrolyte solution containing PST can further reduce the problem of damage and corner cracking of the outer foil shell in the later phases of the battery cycle as compared to the sole use of either component. This may be because PST can prevent the local wetting of the electrode solution on the negative electrode plate caused by the recesses, ensure uniform distribution of the electrolyte solution within the negative electrode plate, improve the general wettability of the electrode solution on the negative electrode plate, promote the formation of a highly homogeneous phase within the negative electrode plate, and increase the structural stability of the negative electrode plate. However, the improvement effect is still not significant, and the reasons for this may be as follows: First, there is a mutual dependency between the negative electrode plate and the electrolytic solution. Specifically, the wettability of the electrolyte solution in the negative electrode active material layer increases as the inner surface area of the recesses on the negative electrode plate increases. However, this further increases the possibility of side reactions between the electrolyte solution and the negative electrode active material layer, and the corrosion of the negative electrode current collector by the electrolyte solution. To alleviate these problems, a higher proportion of PST in the electrolyte solution is required to provide stronger binding effects. However, excessive PST results in increased battery impedance and causes lithium plating, thereby significantly degrading battery cycle performance. Second, the negative electrode plate and the electrolyte solution have some restrictive relationship with the silicon content. In order to improve the energy density of the battery, it is necessary to increase the silicon content in the negative electrode active material layer. Further, as the silicon content increases, the volume expansion of the negative electrode plate increases. On the one hand, it is necessary to increase the volume of the recesses to provide more buffer space to reduce the volume expansion of the negative electrode plate; on the other hand, it is necessary to add more PST to form a stronger protective film that inhibits the volume expansion of the silicon-based material and protects the negative electrode plate from damage by the electrolyte solution. Therefore, it is necessary to regulate the relationship among the silicon content A in the negative electrode active material layer, the dimensions of the recesses (a depth B, a width C, and a distance D), and a content of 1,3-propene sultone E in the electrolyte solution, in order to achieve optimum compatibility between these three parameters. In this way, the problem of damage and cracking at the corners of the outer foil shell in the later phases of the battery cycle can be effectively improved based on the improvement in the energy density of the battery. If C / (A×E×B×D) is too small (for example, less than 0.05), the liquid storage capacity of the negative electrode plate is large, whereby the negative electrode plate becomes soft and the separator is distorted, resulting in a bridge-breaking lithium coating and seriously impairing the electrical performance of the battery. When C / (A×E×B×D) is too large (for example, greater than 100), the electrolyte solution may not sufficiently wet the negative electrode plate, and the inhibition of side reactions is not sufficient, so that the protection performance of the negative electrode plate may not be optimized.In one embodiment, 0.1≤C / (A×E×B×D)≤45.In one embodiment, 0.15≤C / (A×E×B×D)≤17.In the present disclosure, in the calculation of "C / (A×E×B×D)", only the numerical values of A, B, C, D, and E are used without their units being included in the calculation. For example, in Example 1, C / (A×E×B×D)=80 / (5×0.2×10×0.8)=10.In the present disclosure, the silicon content in the negative electrode active material layer (A) refers to the content of the silicon element in the negative electrode active material layer that can be determined by conventional methods in the art, for example, the thermoplastically gravimetric analysis (TGA). The specific method is as follows: The battery was discharged to 0% state of charge (SOC) and then decomposed to extract the negative electrode plate. The negative electrode plate was heat-treated at 400° C. under a nitrogen atmosphere for 2 hours to separate the negative electrode active material layer from the negative electrode current collector. The negative electrode active material layer was then collected as a test sample. With a thermoplastically gravimetric analyzer (for example, a TGA550), a sample having a weight of 5 mg to 15 mg was analyzed under an air or oxygen atmosphere. The temperature was raised from room temperature (25° C.) to 900° C. at a heating rate of 10° C. / min, followed by a 40 minute isothermal hold time at 900° C. Thereby, the non-silicon-containing components in the negative electrode active material layer were allowed to evaporate while ensuring that silicon was completely oxidized to silicon dioxide. Based on the wt % at the end of the entire test process, by dividing by the molecular weight of silicon dioxide and then multiplying by the molecular weight of silicon, the silicon content in the negative electrode active material layer A (in unit of %) was obtained.In the present disclosure, the depth of the recesses refers to the maximum vertical distance from any point within a recess to the surface of the negative electrode active material layer. Depth may be measured using conventional techniques, for example a 3D microscope.In the present disclosure, the recesses may include a concave hole or a groove.In one embodiment, the recesses comprise the grooves.In one embodiment, the recesses are the grooves.In the present disclosure, the orthographic projection of the groove onto the negative electrode active material layer may include two long edges. The width of the groove refers to the average distance between one long edge and the other long edge along either the length direction or the width direction of the negative electrode active material layer. FIG. 3 illustrates schematic diagrams of a width of a groove according to an embodiment of the present disclosure, wherein the two long edges of the grooves in FIGS. 3(a)-3(c) are straight lines and the two long edges of the nut in FIG. 3(d) are curved lines. In FIGS. 3( a) and 3( b), the two long edges are arranged parallel to each other. Therefore, in the longitudinal direction of the negative electrode plate, the distance from each point on one longitudinal edge to the other longitudinal edge is equal. In this case, the width of the groove is the distance (d) from each point on one longitudinal edge to the other longitudinal edge in the longitudinal or width direction of the negative electrode plate. In Fig. 3(c), the two long edges of the groove are straight lines but are not arranged in parallel. Therefore, the distance from any point on one long edge to the other long edge is not the same. In this case, the width of the groove can be obtained by averaging. That is, 50 points are selected at equal intervals based on the length of a long edge (the distance between each point is equal, an equal distance ensures the calculation accuracy), the width (d) at each point is measured, and the average value is taken to obtain the width of the groove. In FIG. 3(d), the two long edges are curved lines. Therefore, the distance from any point on one long edge to the other long edge may not be the same. In this case, the width of the nut can be further obtained by averaging. That is, 50 points are randomly selected on one long edge (since the two long edges in 3(d) are curved lines and there is no relationship like that of the two long edges in 3(c), 50 points can be randomly selected for measurement), the width (d) at each point is measured, and the average value is taken to obtain the width of the mother. The width of the mother can be measured by conventional means of the art, for example, a scanning electron microscope or a 3D microscope.In the present disclosure, the distance of the grooves refers to the average distance between the adjacent two long edges of two adjacent grooves on the negative electrode active material layer in the length or width direction of the negative electrode plate. As illustrated in FIG. 4, it shows schematic diagrams of a distance of two grooves according to an embodiment: FIG. 4( a) shows the case where the two adjacent long edges are straight lines and extend in parallel, FIG. 4( b) shows the case where the two adjacent long edges are straight lines but extend not in parallel, and FIG. 4( c) shows the case where the two adjacent long edges are curved lines. In Fig. 4(a), the two adjacent long edges are straight lines and arranged in parallel. Therefore, the distance from each point on one long edge to the other long edge in the longitudinal direction is equal. In this case, the pitch of the grooves is the pitch (D) from each point on one long edge to the other long edge in the longitudinal direction. In Fig. 4(b), the adjacent two long edges are straight lines but are not arranged in parallel. Therefore, the distance from each point on one long edge to the other long edge is not equal. In this case, the pitch of the grooves can be obtained by averaging. That is, 50 points are selected at equal intervals based on the length of a long edge (the distance between each point is equal, an equal distance ensures the calculation accuracy), the width (D) at each point is measured, and the average value is formed to obtain the interval of the grooves. In Fig. 4(c), the two adjacent long edges are curved lines. Therefore, the distance from any point on one long edge to the other long edge may not be the same. In this case, the pitch of the grooves can be further obtained by averaging the average value. That is, 50 points are randomly selected on one long edge (since the two long edges in 4(c) are curved lines and there is no relationship like that of the two long edges in 4(b), 50 points can be randomly selected for measurement), the width (D) at each point is measured, and the average value is taken to obtain the pitch of the grooves. The distance of the grooves can be measured by conventional means of the art, for example by means of a scanning electron microscope or a 3D microscope.In the present disclosure, there are no particular restrictions on the methods for manufacturing the grooves as long as the objects of the present disclosure can be achieved. The methods for forming the grooves may include, for example, at least one of laser etching methods, mechanical processing, or void forming agent methods.In one embodiment, the method of forming the grooves includes laser processing. The width and depth of the grooves increase with higher laser power, while different distances of the grooves can be obtained by adjusting either the laser processing rate or the feed rate of the negative electrode plate. Therefore, the width, depth and pitch of the grooves can be accurately controlled by adjusting the laser power, the processing rate and the feed speed of the negative electrode plate.In the present disclosure, the shape of the grooves is not particularly limited. The cross-sectional shape of the grooves along the thickness direction of the negative electrode plate may be rectangular or quasi-conical.In the present disclosure, the mass percentage of 1,3-propene sultone in the total mass of the electrolyte solution (E) may be determined using conventional analytical methods in the art, for example gas chromatography-mass spectrometry (GC-MS).In the present disclosure, the silicon-based material includes at least one of nanosilicon, silicon alloy, silicon oxide (SiO x, 0< x<2), or silicon carbon. The silicon carbon refers to a composite material comprising silicon and carbon elements.In the present disclosure, the silicon-based material includes the silicon carbon.In the present disclosure, the silicon carbon includes the following material: silicon particles embedded in a porous carbon framework.In the present disclosure, the negative electrode active material layer may further include a carbon-based material. The carbon-based material may include at least one of artificial graphite, natural graphite, mesocarbon microspheres, soft carbon, or hard carbon.In an embodiment, the negative electrode active material layer includes the silicon-based material and the artificial graphite.The present inventors have found that when C / (A×E×B×D) falls within a certain range and when the parameters B, C, and D are maintained within their respective defined ranges, the following synergistic effects are obtained: on the one hand, a significantly improved local infiltration of the electrolyte solution into the negative electrode active material layer, which improves the overall wettability of the electrolyte solution over the entire negative electrode plate, promotes uniform distribution of the electrolyte solution within the negative electrode plate, and facilitates formation of a highly homogeneous phase within the negative electrode plate, thereby further optimizing the utilization rate of the battery capacity. On the other hand, the volume expansion in the negative electrode plate is effectively reduced. In particular, when the depth of the recesses B is kept within the intended range, this not only improves wettability of the electrolyte solution to speed up the kinetics of lithium ion intercalation / deintercalation and improve the dynamic performance of the negative electrode plate, but also increases the utilization efficiency of the negative electrode active material layer, thereby increasing the energy density of the batteries. In addition, when the width C and the pitch D of the recesses are properly controlled within certain ranges, they have no influence on the adhesive performance between the negative electrode plate and the separator. If the width is too large and the distance is too small, the adhesive force at this position with the separator is relatively weak, and lithium plating occurs. If the width is too small and the distance is too large, sufficient electrolyte solution absorption and lithium ion receiving capacity may not be provided, which also leads to risks of lithium plating.In the present disclosure, B may be in the range of 5 μm to 50 μm, for example, 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, or 50 μm. C. may be between 40 μm and 200 μm, for example 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm, 150 μm, 160 μm, 170 μm, 180 μm, 190 μm or 200 μm. D can be between 0.5 mm and 5 mm, for example 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm or 5 mm.In one embodiment, B is in the range of 10 μm to 30 μm.In one embodiment, C is in the range of 80 μm to 150 μm.In one embodiment, D is in the range of 0.8 mm to 2 mm.Assuming that C / (A×E×B×D) falls within a certain range, the energy density of the battery can be improved when A is within a defined range.In the present disclosure, A may be in the range of 0.8% to 25%, for example, 0.8%, 1%, 1.5%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 20% or 25%.In one embodiment, A is in the range of 1.2% to 20%.In one embodiment, A is in the range of 3% to 15%.Provided that C / (A×E×B×D) falls within a certain range, when E is within a defined range, the likelihood of side reactions between the electrolyte solution and the negative electrode active material layer can be reduced without substantially degrading the impedance of the battery, while further degrading the corrosive effect of the electrolyte solution on the negative electrode current collector. Thereby, fractures caused by corrosion are prevented in the electrode plate (in particular, in the region of the bending of the jelly roll) and the stress concentration in the negative electrode plate is decreased, thereby further improving the protection of the negative electrode plate.In the present disclosure, E may be in the range of 0.1% to 5%, for example, 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%.In one embodiment, E is in the range of 0.2% to 3%.1,3-Propane sultone (PS) can synergistically enhance the strength of the protective film formed by 1,3-propane sultone. The combined use of these compounds further improves the suppression of volume expansion in silicon-based material and improves the protection of the negative electrode plate.In the present disclosure, the electrolyte solution may further include 1,3-propane sultone. A mass percentage of 1,3-propane sultone in the total mass of the electrolyte solution is F (unit: %), where 0.5%≤F≤6%, for example, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, or 6%.In one embodiment, 1%≤F≤4%.In the present disclosure, the mass percentage of 1,3-propane sultone in the total mass of the electrolyte solution F may be determined by conventional methods in the art, for example, gas chromatography-mass spectrometry (GC-MS).When E / F falls within a certain range, the synergistic effect between the two compounds can be exerted at a relatively optimum level. Under such conditions, the polymer monomers formed after ring-opening polymerization of PS and PST have longer and more stable chains that can form a more resistant and stronger protective film. Thereby, side reactions are effectively suppressed and corrosion of the electrolyte solution on the negative electrode current collector is mitigated, thereby preventing cracking at the corners of the outer foil shell in later phases of the battery cycles. Moreover, it improves the sealing performance of the battery after cycling, prevents the entry of moisture, and improves cycle stability and storage performance of the battery under high temperature and high humidity conditions.If E / F is too small (e.g., less than 0.02), the synergy effect cannot be fully utilized. Conversely, if the E / F is too high (e.g., greater than 6), the resulting protective film will have too high an impedance, which will degrade the performance of the battery at low temperatures.In the present disclosure, 0.02≤E / F≤6 is, for example, 0, 0.02, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, or 6.In one embodiment, 0.05≤E / F≤3.The present inventors have found that when the strain rate of the negative electrode plate after 1000 cycles at 25° C. is in a certain range, this can further alleviate the problem of damage and corner cracks of the outer foil in the later phases of the battery cycle.In the present disclosure, an elongation rate of the negative electrode plate after 1000 cycles at 25° C. may be, for example, between 2% and 5%, i.e., 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, or 5%. And a cycle condition includes: the battery was charged to an upper limit voltage at a constant current of 1.5 C, with a cut-off current of 0.05 C, the battery was left aside after full charge for 5 minutes, and then discharged to a cut-off voltage of 3.0 V at a constant current of 0.7 C, and the upper limit voltage is 4.5 V.In one embodiment, the strain rate of the negative electrode plate after 1000 cycles at 25° C. is in the range of 2% to 4%.In the present disclosure, the strain rate of the negative electrode plate can be measured by conventional methods in the art, particularly as follows: the battery is disassembled, then the negative electrode plate is taken out, which is then cut into strips having a length of 60 mm±5 mm and a width of 15 mm±0.25 mm. Then, a universal mechanical testing machine is used to conduct a tensile test with a gauge length of 30 mm and a speed of 30 mm / min.In the present disclosure, the negative electrode current collector may include a copper foil.In the present disclosure, the negative electrode active material layer may further include a negative electrode conductive agent and a negative electrode binder. The negative electrode conductive agent may include at least one selected from the group consisting of conductive carbon black, acetylene black, ketjen black, conductive graphite, carbon nanotubes (including at least one of single-wall carbon nanotubes and multi-wall carbon nanotubes), and carbon fiber. The negative electrode binder may include at least one selected from the group consisting of polyvinylidene fluoride (PVDF), sodium carboxymethyl cellulose, styrene-butadiene rubber, polytetrafluoroethylene, and polyoxyethylene.In the present disclosure, based on a total weight of the negative electrode active material layer: a proportion of the negative electrode active material layer may be in the range of 80% to 99.8% (for example, 80%, 82%, 84%, 86%, 88%, 90%, 92%, 94%, 96%, 98%, 99%, or 99.8%); a proportion of the negative electrode conductive agent may be between 0.1% and 10% (for example, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.1%); a proportion of the negative electrode binder may be from 0.1% to 10% (for example, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.1%).In the present disclosure, the electrolyte solution may further include at least one compound selected from the group consisting of a nitrile compound, a sulfur-containing compound, and a carbonate compound. The nitrile compound may comprise at least one compound selected from the group consisting of succinonitrile, glutaronitrile, adiponitrile, pimeonitrile, suberonitrile, glycerol trinitrile, ethoxy(pentafluoro)phosphazene, 1,2,3,4,5-penta(2-cyanoethoxy)pentane, tris(2-cyanoethyl)phosphate and 1,3,6-hexane tricarbonitrile. The sulfur-containing compound may comprise at least one compound selected from the group consisting of ethylene sulfate and ethylene sulfite. The carbonate compound may include at least one selected from the group consisting of ethylene carbonate, fluoroethylene carbonate, and vinylethylene carbonate.The nitrile compound is capable of forming complexes on the surface of the positive electrode plate by coordination, thereby providing protection for the positive electrode plate. The carbonate compound may be reduced on the surface of the negative electrode to form a protective film. The sulfur-containing compound can enhance the protective effect on both the positive electrode plate and the negative electrode plate.In the present disclosure, the electrolyte solution may further include an organic solvent. The organic solvent may include at least one solvent selected from the group consisting of a carbonate ester, a carboxylic acid ester, and a fluoroether. The carbonate ester may include at least one ester selected from the group consisting of ethylene carbonate (EC), propylene carbonate (PC), dimethyl carbonate, ethylmethyl carbonate, diethyl carbonate, and methylpropyl carbonate. The carboxylic acid ester may include at least one selected from the group consisting of ethyl propionate (EP) and propyl propionate (PP). The fluoroether may comprise 1,1,2,3-tetrafluoroethylene-2,2,3,3-tetrafluoropropylether.In the present disclosure, the electrolyte solution may further include a lithium salt. The lithium salt may include at least one selected from the group consisting of lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, and lithium hexafluorophosphate (LiPF 6). In the electrolyte solution, the mass fraction of the lithium salt is in the range from 10% to 20%, for example 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19% or 20%.In the present disclosure, the battery may further include a positive electrode plate. The positive electrode plate may include a positive electrode current collector and a positive electrode active material layer disposed on at least one surface of the positive electrode current collector, and the positive electrode active material layer includes a positive electrode active material.In an embodiment, the positive electrode active material comprises a lithium cobalt oxide and / or a lithium cobalt oxide doped and / or coated with at least two elements selected from the group consisting of Al, Mg, Mn, Cr, Ti, Zr, Y, La, and B.In one embodiment, the positive electrode active material comprises a material represented by the formula Li a Co b M 1c1 M 2c2 M 3c3 M 4c4 O 2 where 0.9≤a≤1.05 (e.g., 0.9, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 1, 1.01, 1.02, 1.03, 1.04, or 1.05), 0.8≤b≤1.2 (e.g., 0.8, 0.9, 1, or 1.2), 0≤c1≤0.1 (e.g., 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09 or 0.1), 0 ≤ c2 ≤ 0.1 (for example 0.0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09 or 0.1), 0 ≤ c3 ≤ 0.1 (for example 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09 or 0.1), 0 ≤ c4 ≤ 0.1 (for example 0.0, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09 or 0.1), and M 1, M 2, M 3 and M 4 each independently comprise at least one of Al, Mg, Mn, Cr, M, M, M, and M , Ti, Zr, Y, La or B.In one embodiment, 0.01≤c1≤0.1.In one embodiment, 0.005≤c2≤0.1.In one embodiment, 0.01≤c2≤0.1.In the present disclosure, the positive electrode active material layer may further include a positive electrode conductive agent and a positive electrode binder. The positive electrode conductive agent may include at least one selected from the group consisting of conductive carbon black, acetylene black, ketjen black, conductive graphite, carbon nanotubes (including at least one of single-wall carbon nanotubes and multi-wall carbon nanotubes), and carbon fiber. The positive electrode binder may include at least one selected from the group consisting of polyvinylidene fluoride (PVDF), sodium carboxymethylcellulose, styrene-butadiene rubber, polytetrafluoroethylene, and polyoxyethylene.In the present disclosure, based on a total weight of the positive electrode active material layer: a proportion of the positive electrode active material may be between 80% and 99.8% (for example, 80%, 82%, 84%, 86%, 88%, 90%, 92%, 94%, 96%, 98%, 99%, or 99.8%); a proportion of the positive electrode conductive agent may be between 0.1% and 10% (for example, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.1%); a proportion of the positive electrode binder may be in the range of 0.1% to 10% (for example, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, or 0.1%).In one embodiment, a shutdown voltage of the battery is greater than or equal to 4.48 V.In the present disclosure, the battery may further include a separator. The separator may be selected from conventional separators used in the art including at least one separator selected from the group consisting of a polyethylene membrane and a polypropylene membrane.In the present disclosure, the battery may further include an outer foil shell. The outer foil shell may comprise an aluminum plastic foil. A thickness of the outer foil shell may be in the range from 50 μm to 150 μm, for example 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm, 110 μm, 120 μm, 130 μm, 140 μm or 150 μm.In one embodiment, the thickness of the outer film shell is in the range of 85 μm to 115 μm.The inventors of the present disclosure have found that the thickness of the outer foil shell in a particular range can further reduce the problem of damage and corner cracks to the outer foil shell in the later phases of the battery cycle. In addition, the outer foil shell has improved corrosion resistance to the electrolyte solution within this range of thickness, which contributes to reducing side reactions, minimizing electrolyte solution corrosion, reducing gas generation, and improving safety performance.In the present disclosure, the battery may include the outer foil shell and a cell. The cell is accommodated in the outer foil shell and includes the positive electrode plate, the separator, and the negative electrode plate. The positive electrode plate, the separator, and the negative electrode plate may be stacked in the order in which they are arranged in the battery, or may be wound to form a flat portion and a bent portion. The electrolyte solution is injected into the cell to form the battery.In one embodiment, the battery is a pouch battery.In the present disclosure, the battery may be a stacked pouch battery or a wound pouch battery. When the battery is a wound pouch battery, the improvement is more pronounced in the mitigation of corner cracks of the outer foil shell.In one embodiment, the battery is a lithium ion battery.In one embodiment, the battery is a lithium ion secondary battery.By regulating the relationship among: the silicon content in the negative electrode active material layer, the dimensions of the recesses, and the content of 1,3-propene sultone in the electrolyte solution, the present disclosure achieves a significant improvement in the mitigation of cracks in the outer foil shell during later battery cycles while maintaining a high energy density. This improvement improves the sealing performance of the battery, prevents the entry of moisture, and improves cycle stability, low temperature discharge performance, and storage performance under high temperature and high humidity conditions of the battery.Hereinafter, the present disclosure will be described in detail based on embodiments. The embodiments described in the present disclosure are only some, but not all, embodiments of the present disclosure. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present disclosure without any creative efforts fall within the scope of the present disclosure.In the following examples, unless otherwise indicated, analytical grade reagents were used alone.The following examples are provided to illustrate the battery of the present disclosure.Example 1The battery was prepared according to the following method:(1) Production of a positive electrode plateA positive electrode active material (lithium cobalt oxide, LiCo 0,977 Al 0,015 Mg 0,005 Mn 0,003 O 2), a positive electrode binder (PVDF), and a positive electrode conductive agent (acetylene black) were added in a ratio of 97.2:1, 3:1.5; N-methylpyrrolidone (NMP) was stirred by a vacuum mixer until a mixed system became a positive electrode slurry having uniform fluidity; the positive electrode slurry was uniformly coated on an aluminum foil having a thickness of 12 μm; and the coated aluminum foil was dried, then rolled and cut to obtain the positive electrode plate.(2) preparing a negative electrode plateA negative electrode active material layer (a combination of silicon carbon and artificial graphite in a ratio of 1:9), a negative electrode conductor (a combination of single-wall carbon nanotubes (SWCNT) and conductive carbon black (SP) in a ratio of 0.1:1), and a negative electrode binder (a combination of sodium carboxymethyl cellulose (CMC-Na) and styrene butadiene rubber (SBR) in a ratio of 1:2) were used in a ratio of 95.9:1.1:3; a wet method was used to prepare a negative electrode slurry; the negative electrode slurry was uniformly applied to two surfaces of a copper foil having a thickness of 6 μm; the coated copper foil was dried, roll-pressed, punched, and cold-pressed; Subsequently, grooves were etched on the surface of the negative electrode active material layer by the laser processing technique, and then the copper foil was slit, cut, and welded with a tab to obtain the negative electrode plate. The values of the parameters A, B, C and D are shown in Table 1.(3) preparing an electrolyte solutionIn an argon-filled glove box (humidity <10 ppm, oxygen <1 ppm), EC, PC, PP and EP were uniformly mixed in a ratio of 1:1:2:1; LiPF 6, fluoroethylene carbonate and 1,3,6-hexanetricarbonitrile, which constituted 15%, 10% and 2% of the total mass of the electrolytic solution, respectively, were added slowly; then, PST and PS were added (the amounts of PST and PS are shown in Table 1), and the mixture was stirred to obtain the electrolytic solution.(4) Preparation of a batteryThe positive electrode plate prepared in step (1), a separator (a polyethylene-based 5 μm thick film coated on both sides with a 1 μm thick composite layer containing titanium oxide and poly(vinylidene fluoride-co-hexafluoropropylene)), and the negative electrode plate prepared in step (2) were wound to form a bare cell; the bare cell was placed in an aluminum-plastic film (thickness: 105 μm), and the electrolytic solution prepared in step (3) was injected into the bare cell which was dried, followed by a process such as vacuum packaging, standing, formation, molding, and sorting to obtain the battery.Example 2For this example, reference is made to Example 1. There are the following differences: The dimensions of the grooves were changed and the proportions of PST and PS in the electrolyte solution were adjusted as shown in Table 1. The thickness of the aluminum plastic film was changed from 105 μm to 113 μm, and the positive electrode active material LiCo 0,977 Al 0,015 Mg 0,005 Mn 0,003 O 2 was replaced with an equivalent mass of LiCo 0,96 Al 0,015 Mg 0,015 Mn 0,01 O 2.Example 3For this example, reference is made to Example 1. There are the following differences: The dimensions of the grooves were changed and the proportions of PST and PS in the electrolyte solution were adjusted as shown in Table 1. The thickness of the aluminum plastic film was changed from 105 μm to 95 μm, and the positive electrode active material LiCo 0,977 Al 0,015 Mg 0,005 Mn 0,003 O 2 was replaced with an equivalent mass of LiCo 0,98 Al 0,01 Mg 0,01 O 2.Example 4For this example, reference is made to Example 1. There are the following differences: The dimensions of the grooves were changed and the proportions of PST and PS in the electrolyte solution were adjusted as shown in Table 1. The thickness of the aluminum plastic film was changed from 105 μm to 88 μm, and the positive electrode active material LiCo 0,977 Al 0,015 Mg 0,005 Mn 0,003 O 2 was replaced with an equivalent mass of LiCo 0,95 Al 0,02 Mg 0,015 Mn 0,015 O 2.Example 5 GroupThe examples in this group were used to verify the influence caused by the change in C / (A×E×B×D).For this group of examples, reference is made to Example 1. Differences are that the dimensions of the grooves and the proportions of PST and PS in the electrolyte solution were changed as shown in Table 1.Example 6 GroupThe examples in this group were used to examine the influence caused by the change of A.For this group of examples, reference is made to Example 1. One difference is that A was changed by adjusting the ratio of silicon carbon to artificial graphite as shown in Table 1.Example 7 GroupThe examples in this group were used to examine the influence caused by the changes of B and C.For this group of examples, reference is made to Example 1. The differences are that B and C were changed as specifically shown in Table 1.Example 8 GroupThe examples in this group were used to examine the influence produced by the change of D.For this group of examples, reference is made to Example 1. One difference is that D was changed as shown in Table 1.Example 9 GroupThe examples in this group were used to examine the influence caused by the change of E.For this group of examples, reference is made to Example 1. One difference is that E was changed as specifically shown in Table 1.Example 10 GroupThe examples in this group were used to examine the influence caused by the change of F or E / F.For this group of examples, reference is made to Example 1. The differences are that E and / or F were changed as specifically shown in Table 1.Example 11 GroupThe examples in this group were used to check the influence of not adding a nitrile compound or a carbonate compound in the electrolyte solution.For this group of examples, reference is made to Example 1. One difference is that the composition of the electrolyte solution has been changed. The details are as follows.In Example 11a, no fluoroethylene carbonate was added to the electrolyte solution.In Example 11b, 1,3,6-hexanetricarbonitrile was not added to the electrolyte solution.Example 12For this example, reference is made to Example 1. One difference is that the negative electrode active material layer was replaced with the same mass of a combination of SiO and artificial graphite, the ratio of SiO to artificial graphite being 1:11.7.Example 13For this example, reference is made to Example 1. One difference is that in step (4), the positive electrode plate, the separator, and the negative electrode plate were stacked in the order of the positive electrode plate, the separator, the negative electrode plate, and the separator to obtain the bare cell.Comparative Example 1For this comparative example, reference is made to Example 1. Differences are that the dimensions of the grooves and the proportions of PST and PS in the electrolyte solution were changed as specifically shown in Table 1.Comparative Example 2For this comparative example, reference is made to Example 1. One difference is that no grooves were present on the surface of the negative electrode plate.Comparative Example 3For this comparative example, reference is made to Example 1. One difference is that no PST was added to the electrolyte solution.Comparative Example 4For this comparative example, reference is made to Example 13. The differences are that the dimensions of the grooves and the proportions of PST and PS in the electrolyte solution were changed as shown in Table 1.Note that the silicon carbon used in the above Examples and Comparative Examples was the following material: silicon particles embedded in porous carbon skeleton. Table 1 Table 1Example 1510800,80,21040,05Example 25151001.211,1130,33Example 35201201.520,421Example 4530150230,1713Example 5a*2080230,1313Example 5b*101500,80,218,7540,05Example 6a3****16,67**Example 6b10****5**Example 6c15****3,33**Example 6d1,2****41,67**Example 6e20****2,5**Example 6f0,8****62,5**Example 6g25****2**Example 6h0,5****100**Example 6i28****1,79**Example 7a*5200**50**Example 7b*5040**1**Example 8a***0,5*16**Example 8b***5*1,6**Example 9a****0,1202*Example 9b****50,4*1,25Example 10a******0,50,4Example 10b******60,03Example 10c****30,670,56Example 10d******0 / Example 11a********Example 11b********Example 12********Example 13********Comparative Example 1*52000,50,116020,05Comparative Example 2* / / / * / **Comparative Example 3****0 / *0Comparative Example 4*52000,50,116020,05Note: the "*" in Table 1 indicates that the corresponding parameter value agrees with that in Example 1; the " / " indicates that it does not exist.Test Example(1) 25 °C Cycle TestThe batteries prepared in the examples and comparative examples were stored in an environment of (25±22° C. for 2 to 3 hours. When the bodies of the batteries reached (25±2) °C, the batteries were charged to an upper limit voltage at a constant current of 1.5C, with a cut-off current of 0.05C. The batteries were left on for 5 minutes after complete charging and then discharged at a constant current of 0.7 C to a cut-off voltage of 3.0 V. The highest discharge capacity in the first three cycles was recorded as the initial capacity Q. After the completion of 1000 cycles, the last discharge capacity Q1 of the batteries was recorded. Observations were made as to whether damage occurred to the battery bodies by the aluminum-plastic sheet, and the strain rate of the negative electrode plate was measured. The results were recorded in Table 2 with the capacity retention rate (%)=(Q1 / Q)×100%.(2) Storage at high temperature and high humidity: 35 days at 60° CThe batteries prepared in the Example and Comparative Example were discharged at 0.5C, allowed to stand for 5 minutes, and then charged at 0.7C. This cycle was repeated twice, the second discharge capacity was recorded as the initial capacity Q2. Complete charging of the batteries (a thickness of T0) was left at idle for 35 days under a condition of (60±2) °C and 90%-95% RH, the batteries were left at idle for 2 hours at room temperature, the thicknesses of the stored batteries after cooling were measured and recorded as T. The batteries were discharged to 3.0 V at a constant current of 0.5 DEG C. and the remaining capacity was recorded. Then, the batteries were charged at 0.7 DEG C., left aside for 5 minutes, and then discharged at 0.5 DEG C. This cycle was repeated three times. The highest capacity in the three cycles was recorded as the recovered capacity Q3. The capacity retention rates of the batteries after storage at high temperature and high humidity were calculated, and it was determined whether the battery bodies produced gas. The results are shown in Table 2. Among them, a capacity retention rate (%)=Q3 / Q2×100%; a thickness change rate (%)=(T-T0) / T0×10%.If the thickness change rate is less than 10%, the battery status is marked as "no gas generation"; if the thickness change rate falls within the range of 10% to 15% (including both endpoints), the battery status is marked as "gas generation"; and if the thickness change rate is greater than 15%, the battery status is marked as "strong gas generation".(3) Low-temperature discharge test at -10°CThe batteries prepared in the Example and Comparative Example were subjected to 10 cycles of charge-discharge at a rate of 0.7 C. under room temperature. The batteries were then charged to full capacity at a rate of 0.7 DEG C., the charged capacity being recorded as Q4. The fully charged batteries were then left aside at -10°C for 4 hours and then discharged to 3V at a rate of 0.4C. The discharged capacity was recorded as Q5. The discharge capacity retention rate at low temperatures was calculated from the following formula and the results were recorded in Table 2. Capacity retention rate (%)=(Q5 / Q4)×10%.Note: The upper voltage limit for all the above tests was 4.5 V.

[0156] Table 2

[0156] Table 2Example 184,8No damage64,9No gas generation72,52,6Example 282,6No damage62,7No gas generation71,42,8Example 381,8No damage61,9No gas generation70,82,7Example 481,4No damage61,1No gas generation70,22,9Example 5a71,4No damage51,1No gas generation61,83,2Example 5b74,2No damage54,4No gas generation64,53,5Example 6a85,1No damage65,5No gas generation732,5Example 6b82,2No damage62,2No gas generation71,52,7Example 6c79No damage59,1No gas generation69,13Example 6d85,3No damage65,7No gas generation73,32,5Example 6e76,4No damage55,8No gas generation65,83,3Example 6f85,4No damage65,3No gas generation73,12,6Example 6g74,8No damage55,2No gas generation64,33,5Example 6h84,9No damage65,3No gas generation73,12,7Example 6i71,4No damage51,5None of them were61,33,9Generation of GasExample 7a72,8No damage52,2No gas generation62,33,4Example 7b73,8No damage53,3No gas generation63,73,8Example 8a73,6No damage55,9No gas generation65,13,2Example 8b71,6No damage50,7No gas generation60,33,8Example 9a74,1No damage53,4No gas generation63,13,3Example 9b71,5No damage51,6No gas generation61,93,5Example 10a76,3No damage57,2No gas generation66,13Example 10b75,1No damage55,8No gas generation64,53,3Example 10c74,6No damage54,33No gas generation63,13,4Example 10d70,1No damage5013No gas generation60,23,9Example 11a68,3No damage49,8No gas generation59,33,9Example 11b66,5No damage46,2No gas generation57,33,9Example 1282,1No damage62,6No gas generation71,32,9Example 1385,6No damage65,3No gas generation74,82Comparative Example 160,3Damage40,8Generation of Gas50,44,9Comparative Example 238,8Damage38,3Transverse gas generation26,96,9Comparative Example 340,8Damage20,7Transverse gas generation30,66,3Comparative Example 463,7Damage43,3Generation of Gas53,14,2It is apparent from Table 2 that, as compared with Comparative Example 1 and Comparative Example 4, when C / (A×E×B×D) was within a certain range, the battery of the present disclosure could significantly alleviate the problem of damage and corner cracks of the outer film in the later phases of the battery cycle. As compared with Comparative Example 2, the battery of the present disclosure had recesses on the surface of the negative electrode active material layer, which significantly improved cycle performance and alleviated the problem of damage and corner cracks of the outer foil in the later phases of the battery cycle. As compared with Comparative Example 3, the electrolyte solution of the battery of the present disclosure comprised PST, which further significantly improved cycle performance and alleviated the problem of damage and corner cracking of the outer film in the later phases of the battery cycle.The foregoing describes in detail a preferred implementation of the present disclosure. However, the present disclosure is not limited thereto. Within the technical concept of the present disclosure, various simple variations of the technical solutions of the present disclosure may be implemented, including combinations of technical features in any other suitable manner. These simple variations and combinations are further considered to be disclosed by the present disclosure and are within the scope of the present disclosure.

Claims

A battery comprising a negative electrode plate and an electrolyte solution; the negative electrode plate comprises a negative electrode current collector and a negative electrode active material layer disposed on at least one surface of the negative electrode current collector; the negative electrode active material layer comprises a negative electrode active material comprising a silicon-based material; and wherein, based on a total weight of the negative electrode active material layer, a proportion of silicon A is in a unit of %; a surface of the negative electrode active material layer has recesses having a depth B in a unit of μm, a width C in a unit of μm, and a distance D in a unit of mm; the electrolyte solution comprises 1,3-propene sultone and a mass percent of 1,3-propene sultone in a total mass of the electrolyte solution E in a unit of %; and wherein the relationship 0.05≤C / (A×E×B×D)≤100 is satisfied.The battery according to claim 1, wherein 0.1 ≤ C / (A×E×B×D) ≤ 45, preferably 0.15 ≤ C / (A×E×B×D) ≤ 17.The battery according to claim 1 or 2, wherein the recesses comprise a concave hole and / or a groove.The battery according to any one of claims 1 to 3, wherein B is in the range of 5 μm to 50 μm, preferably in the range of 10 μm to 30 μm; and / or C is in the range of 40 μm to 200 μm, preferably in the range of 80 μm to 150 μm; and / or D is in the range of 0.5 mm to 5 mm, preferably in the range of 0.8 mm to 2 mm.The battery according to any one of claims 1 to 4, wherein A is in the range of 0.8% to 25%, preferably in the range of 1.2% to 20%, more preferably in the range of 3% to 15%; and / or E is in the range of 0.1% to 5%, preferably in the range of 0.2% to 3%; and / or the silicon-based material comprises at least one of nanosilicon, silicon alloy, silicon oxide or silicon carbon; preferably the silicon-based material comprises silicon carbon; more preferably silicon carbon comprises the following material: silicon particles embedded in a porous carbon framework.The battery according to any one of claims 1 to 5, wherein the electrolyte solution further comprises 1,3-propane sultone, preferably a mass percent of 1,3-propane sultone in the total mass of the electrolyte solution F and in a unit of % is 0.5% ≤ F ≤ 6%; more preferably 1% ≤ F ≤ 4%.The battery according to claim 6, wherein 0.02 ≤ E / F ≤ 6; preferably 0.05 ≤ E / F ≤ 3.The battery according to any one of claims 1 to 7, wherein when the battery cycles at 25°C, the strain rate of the negative electrode plate is in the range of 2% to 5%, and comprises a cycle condition: the battery was supplied to an upper limit voltage at a constant current of 1.5C, wherein a cut-off current was 0.05C, the battery was set aside after the full charge for 5 minutes, and then was discharged to a cut-off voltage of 3.0V at a constant current of 0.7C, and the upper limit voltage is 4.5V; preferably, is in the range of 2% to 4%.The battery according to any one of claims 1 to 8, wherein the negative electrode active material layer further comprises a negative electrode conductive agent and a negative electrode binder; preferably wherein the negative electrode conductive agent comprises at least one selected from the group consisting of conductive carbon black, acetylene black, ketjen black, conductive graphite, carbon nanotubes, and carbon fiber; the negative electrode binder comprises at least one selected from the group consisting of polyvinylidene fluoride, sodium carboxymethyl cellulose, styrene butadiene rubber, polytetrafluoroethylene, and polyoxyethylene; Preferably, based on a total weight of the positive electrode active material layer, a positive electrode active material content is in the range of 80% to 99.8%, a positive electrode conductive agent content is in the range of 0.1% to 10%, and a positive electrode binder content is in the range of 0.1% to 10%.The battery according to any one of claims 1 to 9, wherein the electrolyte solution further comprises at least one compound of a nitrile compound, a sulfur-containing compound, or a carbonate compound; preferably wherein the nitrile compound comprises at least one compound of succinonitrile, glutaronitrile, adiponitrile, pimeonitrile, suberonitrile, glycerol trinitrile, ethoxy(pentafluoro)phosphazene, 1,2,3,4,5-penta(2-cyanoethoxy)pentane, tris(2-cyanoethyl)phosphate, or 1,3,6-hexane tricarbonitrile, preferably the sulfur-containing compound comprises at least one of ethylene sulfate and ethylene sulfite; preferably the carbonate compound comprises at least one of ethylene carbonate, fluoroethylene carbonate, or vinyl ethylene carbonate.The battery according to any one of claims 1 to 10, wherein the electrolyte solution further comprises an organic solvent; preferably, the organic solvent comprises at least one selected from the group consisting of a carbonate ester, a carboxylic acid ester, and a fluoroether.The battery according to any one of claims 1 to 11, wherein the electrolyte solution further comprises a lithium salt; preferably the lithium salt comprises at least one compound selected from the group consisting of lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, and lithium hexafluorophosphate; preferably, in the electrolyte solution, a mass percent of the lithium salt is in the range of 10% to 20%.The battery according to any one of claims 1 to 12, further comprising a positive electrode plate, wherein the positive electrode plate comprises a positive electrode current collector and a positive electrode active material layer disposed on at least one surface of the positive electrode current collector; the positive electrode active material layer comprises a positive electrode active material, preferably the positive electrode active material comprises a material represented by the formula Li a Co b M 1c1 M 2c2 M 3c3 M 4c4 O 2 wherein 0.9 ≤ a ≤ 1.05, 0.8 ≤ b ≤ 1.2, 0 ≤ c1 ≤ 0.1, 0≤c2≤0.1, 0≤c3≤0.1, 0≤c4≤0.1, and M 1, M 2, M 3 and M 4 each independently comprise at least one of Al, Mg, Mn, Cr, Ti, Zr, Y, La or B.The battery according to any one of claims 1 to 13, wherein a cut-off voltage of the battery is greater than or equal to 4.48 V; preferably the battery is a lithium ion secondary battery; preferably the battery is a pouch battery; more preferably the battery is a stacked pouch battery; more preferably the battery is a wound pouch battery.The battery according to any one of claims 1 to 14, further comprising an outer foil shell and a cell, wherein the cell is accommodated in the outer foil shell, the cell comprises a positive electrode plate, a separator, and the negative electrode plate, the positive electrode plate, the separator, and the negative electrode plate are sequentially stacked in the order of the positive electrode plate, the separator, the negative electrode plate, and the separator; preferably, the outer foil shell comprises an aluminum-plastic foil, preferably, the thickness of the outer foil shell is in the range of 50 μm to 150 μm; more preferably, in the range of 85 μm to 115 μm.

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