Energy storage battery and preparation method thereof

Abstract

The invention belongs to the field of energy storage batteries, and discloses an energy storage battery and a preparation method thereof, the energy storage battery comprises a positive pole piece, a negative pole piece and a solid electrolyte, and the solid electrolyte comprises aeolian sand, cement, inorganic insulating fiber, sodium salt and a specific type of additive. According to the energy storage battery, the aeolian sand is used as a solid electrolyte raw material of the battery for the first time, and the cement-based energy storage battery with high safety, high electronic insulativity, high ion transmission capacity and good cycle stability is obtained by matching the aeolian sand with inorganic insulating fibers, sodium salt and a specific type of additives, so that the application scene of the aeolian sand material is expanded; according to the present invention, the resource utilization of the aeolian sand is achieved, the harm caused by desertification can be delayed, the huge economic benefit can be generated, the battery can be directly used for manufacturing the building member, and the energy storage building material integration is achieved.

Description

Technical Field

[0001] The present invention belongs to the field of energy storage batteries, and relates to an energy storage battery and a preparation method thereof. The energy storage battery uses a cement-based solid electrolyte, has the advantages of low cost and high safety, and has high application prospects in the energy storage field. Background Art

[0002] The electrochemical energy storage system is a key system for realizing the conversion, storage, and control of renewable clean energy, and is used to realize the conversion between chemical energy and electrical energy, and requires characteristics such as safety, low cost, high efficiency, and long life. With the development of new energy, the demand for energy storage products is becoming increasingly urgent. The cement-based battery uses a cement-based material as a structural electrolyte and has the ability to charge and discharge. It is a promising integrated structural energy storage composite material and is considered to be one of the solutions for future large-scale energy storage. It can provide emergency power in the event of a power outage in extreme weather, such as meeting the needs of lighting and communication, and enhancing the disaster tolerance of buildings in the event of a power outage during a disaster. Currently, research on cement-based energy storage devices has begun. For example, CN119029326A discloses a cement-based energy storage device, which includes a cathode electrode sheet, an anode electrode sheet, and a cement-based electrolyte matrix. The cathode electrode sheet is connected to the positive current collector, the anode electrode sheet is connected to the negative current collector, and a cement-based electrolyte matrix is provided between the cathode electrode sheet and the anode electrode sheet. The raw materials of the cement-based electrolyte matrix include silicate and water-soluble salt; CN118040066A discloses a cement-based lithium battery, which combines common functional materials in lithium batteries, including lithium cobaltate, lithium iron phosphate, polyethylene oxide, etc. with cement materials, and uses iron powder to prepare the electrolyte of the battery, and polyvinylidene fluoride and styrene-butadiene rubber to prepare the adhesive layer of the battery, forming a new type of rechargeable cement-based lithium battery. This battery has a high energy density, a long service life, and a high compressive strength retention rate, and can be better used in the field of construction engineering and has good application prospects. However, the research on cement-based batteries is still in its infancy and faces many problems, and there is still much room for improvement in its performance.

[0003] Aeolian sand refers to the sand formed by the accumulation of a large amount of rock debris carried by the wind in desert areas. It is mostly formed by the weathering of stones and is commonly found in deserts and gobi areas in China. Its particles are uniform, with a particle size ranging from 0.075 to 0.5 mm, a small fineness modulus, and a relatively concentrated particle size distribution. Different from the commonly used building materials river sand or sea sand, aeolian sand has a narrow particle size range, high density, low porosity, and poor water retention capacity, so river sand and sea sand cannot be directly replaced by aeolian sand. Aeolian sand in deserts is widely distributed and rich in reserves. Desertification is one of the most serious problems faced globally. The desertified area in China has accounted for 27% of the total national land area and is still expanding. If aeolian sand can be effectively utilized, it can turn waste into treasure and reduce the current situation of ecological environment deterioration to a certain extent. The domestic research on the application of aeolian sand is mainly used for subgrade and foundation. Although this method can solve the shortage of river sand and sea sand to a certain extent, it cannot achieve the high-value utilization of aeolian sand. Currently, there are also studies showing that sand can be used as a filler in energy storage batteries. For example, CN115863866A discloses a structural energy storage integrated concrete matrix battery, in which the concrete matrix is formed by foamed concrete, short fibers are incorporated into the foamed concrete, the concrete matrix has an internal pore structure, the battery electrode includes a current collector, a tab, and the concrete matrix, and the surface of the current collector is provided with an electrode active material, a conductive agent, and an adhesive; the concrete matrix provides a space for accommodating the current collector, an alkaline electrolyte is provided in the internal pore structure of the concrete matrix, and the alkaline electrolyte is sealed by a surface covering layer. While maintaining the energy storage performance of the battery, it endows excellent mechanical properties through the concrete matrix. CN116053612A discloses a cement-based battery and its preparation method. The cement-based battery includes a conductive cement-based body and a plurality of battery bodies connected in series in the conductive cement-based body; the conductive cement-based body is cast from a cement-based electrolyte material, and the cement-based electrolyte material, by weight percentage, includes the following components: cement 14.9% - 65.0%, conductive material 0.1% - 2.8%, fine aggregate 0 - 71.7%, water reducing agent 0 - 0.53%, water 21.1 - 40%, and the fluidity of the cement-based electrolyte material is greater than or equal to 160 mm. Its cement-based battery includes a plurality of series-connected battery bodies, which improves the total energy storage capacity and can provide a stable current for a long time without external power supply.CN118800978A discloses a rechargeable cement-based battery, which includes an anode, an electrolyte, and a cathode. The anode and the cathode are respectively arranged at both ends of the electrolyte. The anode is an electroplated metal iron carbon fiber mesh, and the cathode is an electroplated metal nickel carbon fiber mesh. The electrolyte is a cement-based material. The cement-based material includes the following components by weight percentage: cement 14.9% - 65.0%, conductive material 0.1% - 2.8%, fine aggregate 0 - 71.7%, water reducing agent 0 - 0.53%, and water 21.1 - 40%. By electroplating iron and nickel on the carbon fiber mesh to form the positive and negative electrodes of the battery body, the charging and discharging efficiency of the battery is improved. CN117577964A discloses a rechargeable cement-based battery, which includes a cement-based electrolyte and a metal positive electrode and a metal negative electrode inserted at intervals in the cement-based electrolyte, and part of the metal positive electrode and part of the metal negative electrode are exposed from the cement-based electrolyte; or, the battery includes a cement-based positive electrode, a cement-based electrolyte, and a cement-based negative electrode arranged in layers in sequence. Among them, the raw materials of the cement-based electrolyte include portland cement, water, water-soluble salt, and quartz sand. It uses cheap and abundant cement materials to prepare rechargeable cement-based batteries, with low cost and excellent electrical properties at the same time, which can lay the foundation for energy storage in building structures and can be used as an alternative solution to solve the energy crisis. Currently, most cement batteries use the internal porous structure formed by cement curing to pour electrolyte or add a gel electrolyte of conductive salt. This structure requires excellent sealing during the charge and discharge process of the battery to avoid the volatilization loss of the electrolyte, which is not conducive to the long-term use of the battery. Although the aeolian sand resources in the desert are rich, its particle size is too fine, the particle diameter is mostly less than 0.25mm, the grading is poor, the particles are smooth, and the plasticity is poor. It cannot be simply replaced with conventional fillers for energy storage batteries. In addition, solid electrolyte cement energy storage batteries also have low ionic conductivity. When carbon materials are introduced, although the ionic conductivity can be improved, the electronic conductivity will also be increased, which may lead to local short circuits and there are certain safety hazards. There is currently no record of aeolian sand being used in energy storage batteries. If aeolian sand can be applied to energy storage batteries, it will not only delay the harm caused by desertification but also generate huge economic benefits. Therefore, relevant technical solutions are urgently needed to fill the research gap of aeolian sand in the energy storage field. Summary of the Invention

[0004] In order to solve the defects in the prior art, the present invention provides an energy storage battery and a preparation method thereof. The energy storage battery includes a positive electrode plate, a negative electrode plate, and a solid electrolyte that separates the positive electrode plate and the negative electrode plate. The solid electrolyte includes aeolian sand, cement, inorganic insulating fiber, sodium salt, and selected from Na3Zr2Si2PO 12 , Na3Zr2Si3P3O 14 , Li7La3Zr2O 12 , Li 6.4 La3Zr 1.4Ta 0.6 O 12 、 NaFePO4, Na3PS4, Na3PSe4, Na 10 SnP2S 12 、 Na 1.4 Al 0.4 Ti 1.6 (PO4)3 and Na 0.5 Bi 0.5 TiO3, at least one additive. The energy storage battery provides a new cement - based energy storage battery solution. The electrolyte mainly uses aeolian sand and cement as the base materials, which can significantly reduce the cost of the electrolyte, and does not require rare metals, having obvious cost advantages and easy availability of resources. At the same time, the battery has high safety. The all - solid inorganic system cement - based electrolyte does not contain flammable organic solvents, completely eliminating the risk of combustion and explosion. At the same time, the zinc or iron metal negative electrode and the rigid electrolyte act synergistically to effectively inhibit dendrite penetration, and at the same time have good electron insulation and ion transport capabilities, having good specific capacity and cycle stability. In addition, the battery has high mechanical strength and good stability, can effectively prevent internal short - circuit or structural damage of the battery, and the battery module has high compressive strength and can be directly used as building components (such as walls, foundations), realizing the integrated use of "energy storage building materials".

[0005] To achieve the above - mentioned objects of the present invention, the present invention provides an energy storage battery, including a positive electrode plate, a negative electrode plate, and a solid electrolyte separating the positive electrode plate and the negative electrode plate. The solid electrolyte includes: aeolian sand, cement, inorganic insulating fibers, sodium salts, and additives. The additives are selected from Na3Zr2Si2PO 12 、 Na3Zr2Si3P3O 14 、 Li7La3Zr2O 12 、 Li 6.4 La3Zr 1.4 Ta 0.6 O 12 、 NaFePO4, Na3PS4, Na3PSe4, Na 10 SnP2S 12 、 Na 1.4 Al 0.4 Ti 1.6 (PO4)3 and Na 0.5 Bi 0.5 TiO3, at least one of them. The use of sodium salts and specific additives can provide effective sodium - ion transport channels and optimize the ion transport performance of the electrolyte, enhancing the ionic conductivity of the electrolyte and improving the charge - discharge efficiency and capacity retention rate of the battery.

[0006] Further, the positive electrode plate includes a positive current collector and a positive active layer attached to the positive current collector. The positive active layer includes 90 wt% to 95 wt% of activated carbon and 5 wt% to 10 wt% of a binder. The binder is selected from one of polytetrafluoroethylene, polyvinylidene fluoride, and sodium carboxymethyl cellulose. The thickness of the positive active layer is 0.5 to 3 mm, and the positive current collector is copper foil or aluminum foil.

[0007] Further, the negative electrode plate is a metal plate, and the metal is selected from one of iron and zinc. The thickness of the metal plate is 1 to 10 mm.

[0008] Further, the inorganic insulating fiber is selected from at least one of alkali-free glass fiber, alumina fiber, basalt fiber, mullite fiber, and aluminum silicate fiber, and the cement is one of sulfoaluminate cement and silicate cement. The introduction of the inorganic insulating fiber further enhances the toughness and crack resistance of the cement-based electrolyte substrate, with strong stability. At the same time, the simultaneous introduction of aeolian sand and inorganic insulating fiber can also synergistically adjust the pore structure of the cement-based electrolyte substrate, providing more migration paths for ions. At the same time, it was unexpectedly found in the experiment that when aeolian sand and inorganic insulating fiber are used in a specific cement, after normal curing treatment, the concrete obtained has a good pore structure, which has a good promoting effect on the ion transport in the electrolyte, and at the same time, the internal pores do not have an adverse impact on the mechanical structure of the concrete.

[0009] Further, the mass fractions of the components in the solid electrolyte are 40 to 60 wt% of aeolian sand, 20 to 40 wt% of cement, 1 to 5 wt% of inorganic insulating fiber, 1 to 10 wt% of sodium salt, and 5 to 10 wt% of additive. There are no special restrictions on the sources of aeolian sand and cement. The aeolian sand in the present invention is sourced from the Kubuqi Desert and is used directly as a raw material without special treatment. The average particle size of the aeolian sand is 0.07 to 0.20 mm.

[0010] Further, the method for preparing the positive electrode plate is as follows: Weigh activated carbon and binder according to a mass ratio of 90 to 95:5 to 10, add the activated carbon and binder to the organic solvent NMP for blending, form a positive electrode slurry after high-speed stirring, and then uniformly coat the positive electrode slurry on the positive current collector, and obtain the positive electrode plate after drying, rolling, and slitting.

[0011] Further, the thickness of the solid electrolyte is 5 to 50 mm, the sodium salt is one of sodium nitrate and sodium sulfate, and the method for preparing the solid electrolyte is as follows:

[0012] 1) Weigh aeolian sand, cement, inorganic insulating fiber, sodium salt, and additive according to the ratio;

[0013] 2) Mix aeolian sand, cement, inorganic insulating fiber, and additive, then put them into a mixing container for dry mixing for 10 - 60 min to obtain a uniformly mixed mixture; dissolve sodium salt in a certain amount of water to obtain a sodium salt solution with a concentration of 0.5 - 1 M.

[0014] 3) Add the mixture obtained in step 2) into the sodium salt solution, stir for 60 - 200 min until uniformly dispersed to obtain a slurry, pour the slurry into a mold, level it by vibration, and then cure and perform heat treatment to obtain the product.

[0015] Further, the curing specifically is: place the mold leveled by vibration in an environment with a temperature of 25 °C and a humidity of 50 ± 5% and let it stand for 10 - 20 h; then place the mold in an environment with a humidity of 90 ± 5% for curing for 5 - 10 days to completely hydrate the cement; then place it at 60 - 80 °C for drying for 2 - 5 days and then demold; the heat treatment is to place the demolded product at 150 - 250 °C and let it stand for 1 - 5 h.

[0016] The present invention also provides a preparation method of an energy storage battery. The energy storage battery includes a positive electrode plate, a negative electrode plate, and a solid electrolyte located between the positive electrode plate and the negative electrode plate and separating the two. This preparation method includes the following steps:

[0017] S1 Prepare the positive electrode plate: Weigh activated carbon and binder according to a mass ratio of 90 - 95:5 - 10, add the activated carbon and binder to NMP for blending, form a positive electrode slurry after high-speed stirring, and then uniformly coat the positive electrode slurry on a positive electrode current collector, and obtain the positive electrode plate after drying, rolling, and slitting.

[0018] S2 Prepare the solid electrolyte slurry: Weigh aeolian sand, cement, inorganic insulating fiber, sodium salt, and additive according to a ratio; mix aeolian sand, cement, inorganic insulating fiber, and additive, then put them into a mixing container for dry mixing for 10 - 60 min to obtain a uniformly mixed mixture; dissolve sodium salt in a certain amount of water to obtain a sodium salt solution with a concentration of 0.5 - 1 M; add the mixture into the sodium salt solution and stir for 60 - 200 min until uniformly dispersed to obtain a slurry.

[0019] S3 Prepare the battery: Place the positive electrode plate and the negative electrode plate in front of and behind the mold respectively, with the positive electrode active layer facing the negative electrode plate; then pour the slurry into the mold, level it by vibration, adjust the distance between the positive and negative electrode plates, and then cure and perform heat treatment to obtain the product.

[0020] Further, the additive is selected from Na3Zr2Si2PO 12 、Na3Zr2Si3P3O 14 、Li7La3Zr2O 12 、Li 6.4 La3Zr 1.4Ta 0.6 O 12 、 NaFePO4, Na3PS4, Na3PSe4, Na 10 SnP2S 12 、 Na 14 Al 0.4 Ti 1.6 (PO4)3 and Na 0.5 Bi 0.5 TiO3, at least one of them.

[0021] The binder is selected from one of polytetrafluoroethylene, polyvinylidene fluoride, and sodium carboxymethyl cellulose. The thickness of the positive electrode active layer is 0.5 - 3 mm. The positive electrode current collector is copper foil or aluminum foil. The negative electrode plate is a metal plate. The metal is selected from one of iron and zinc. The thickness of the metal plate is 1 - 10 mm. The inorganic insulating fiber is selected from at least one of non-alkali glass fiber, alumina fiber, basalt fiber, mullite fiber, and aluminosilicate fiber. The cement is selected from one of sulfoaluminate cement and Portland cement.

[0022] Furthermore, the mass fractions of the components in the solid electrolyte are as follows: aeolian sand 40 - 60 wt%, cement 20 - 40 wt%, inorganic insulating fiber 1 - 5 wt%, sodium salt 1 - 10 wt%, and additive 5 - 10 wt%.

[0023] Furthermore, the curing specifically is: placing the vibrated and leveled mold in an environment with a temperature of 25°C and a humidity of 50 ± 5% and standing for 10 - 20 h; then placing the mold in an environment with a humidity of 90 ± 5% for curing for 5 - 10 days to make the cement fully hydrated; then drying at 60 - 80°C for 2 - 5 days and demolding; the heat treatment is placing the demolded product at 150 - 250°C and standing for 1 - 5 h.

[0024] Compared with the prior art, the beneficial effects of the technical solution of the present invention are as follows:

[0025] 1. The present invention provides a new cement-based energy storage battery solution, and for the first time, it proposes to apply aeolian sand in an energy storage battery and successfully prepares an energy storage battery based on aeolian sand for the first time, expanding the application scenario of aeolian sand, effectively improving the utilization of aeolian sand resources, being able to delay the harm brought by desertification and generate huge economic benefits, and filling the research gap of aeolian sand in the energy storage field.

[0026] 2. The electrolyte of the present invention mainly uses aeolian sand and cement as base materials. The raw materials are safe and non-toxic. Aeolian sand is a natural resource, which is widely distributed and inexpensive. Cement is a common material in the construction industry, with low production costs. Inorganic insulating fibers are also cheap and easy to obtain. Compared with the currently widely used battery systems, it has low costs, abundant raw materials, and controllable costs. At the same time, the cement-based material can be recycled after the end of its service life. The solid electrolyte does not use organic solvents, and the treatment of waste batteries is simple.

[0027] 3. The battery has high safety, does not contain flammable organic solvents, completely eliminates the risk of combustion and explosion. At the same time, the zinc or iron metal negative electrode and the rigid electrolyte work together to effectively inhibit dendrite penetration. The construction of the solid electrolyte system of the present invention has good electronic insulation and ion transport capabilities. In a specific cement system, the use of aeolian sand and inorganic insulating fibers can produce a synergistic effect, which can adjust the pore structure of the cement-based electrolyte base material, provide more paths for ion transport, and increase ion conductivity.

[0028] 4. The battery of the present invention has high mechanical strength, does not require additional support, and can withstand a certain amount of external force impact. The introduction of inorganic insulating fibers further enhances the toughness and crack resistance of the material. The cement-based solid electrolyte shows good chemical and physical stability during long-term use, and is not prone to structural damage or performance degradation. The battery of the present invention has good stability, has good specific capacity and cycle stability, can effectively prevent internal short circuits or structural damage of the battery, and the battery module has high compressive strength and can be directly used as building components (such as walls, foundations), having a certain application prospect of "energy storage building materials" integration. In addition, it can also be widely used in large-scale supporting energy storage in power grid energy storage or renewable energy systems such as solar / wind energy. Detailed Embodiments

[0029] To make the technical problems solved, the technical solutions adopted, and the achieved technical effects of the present invention clearer, the technical solutions of the embodiments of the present invention will be further described in detail below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present invention.

[0030] It should be noted that referring to "embodiment" in this article means that a specific feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the present application. The phrase appears in various positions in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0031] Unless otherwise specified, the experimental methods in the following examples are all conventional methods. Unless otherwise specified, the materials, reagents, etc. used in the following examples can all be obtained from commercial sources.

[0032] Example 1

[0033] An energy storage battery includes a positive electrode plate, a negative electrode plate and a solid electrolyte. The negative electrode plate is an iron plate with a thickness of 1 mm. The solid electrolyte includes: aeolian sand 53 wt%, sulphoaluminate cement 40 wt%, alkali-free glass fiber 1 wt%, sodium nitrate 1 wt% and Na3Zr2Si2PO 12 5 wt%,

[0034] The preparation method of this energy storage battery is as follows:

[0035] S1 Prepare the positive electrode plate: Weigh activated carbon and polytetrafluoroethylene according to a mass ratio of 90:10. Add the activated carbon and polytetrafluoroethylene to NMP for blending. After high-speed stirring, a positive electrode slurry is formed. Then, the positive electrode slurry is evenly coated on the copper foil. After drying, rolling and slitting, a positive electrode plate with an active layer thickness of 0.5 mm is obtained;

[0036] S2 Prepare the solid electrolyte slurry: Weigh aeolian sand, sulphoaluminate cement, alkali-free glass fiber, sodium nitrate and Na3Zr2Si2PO 12 ; Mix the aeolian sand, sulphoaluminate cement, alkali-free glass fiber, Na3Zr2Si2PO 12 Put them into a mixing container for dry mixing for 10 min to obtain a uniformly mixed mixture; Dissolve the sodium salt in a certain amount of water to obtain a sodium salt solution with a concentration of 0.5 M; Add the mixture to the sodium salt solution and stir for 60 min until it is uniformly dispersed to obtain a slurry;

[0037] S3 Prepare the battery: Place the positive electrode plate and the iron plate in front of and behind the mold respectively, with the positive electrode active layer facing the iron plate; Then pour the slurry into the mold, level it by vibration and adjust the distance between the positive electrode plate and the iron plate to 5 mm. Then place the vibrated and leveled mold in an environment with a temperature of 25 °C and a humidity of 50±5% and let it stand for 10 h; Then place the mold in an environment with a humidity of 90±5% for curing for 5 days to completely hydrate the cement; Then place it at 60 °C for drying for 2 days and then demold; Place the demolded product at 150 °C and let it stand for 1 h.

[0038] Test this battery. The voltage of this energy storage battery is 1.85 V, the specific energy is 22.07 Wh / Kg, the ionic conductivity is 2.3 mS / cm, and the capacity retention rate is 83% after being placed for 1000 h. After standardizing the battery quality, it is calculated that the capacity of this energy storage battery is about 22 Wh.

[0039] Example 2

[0040] An energy storage battery includes a positive electrode plate, a negative electrode plate, and a solid electrolyte. The negative electrode plate is a zinc plate with a thickness of 10 mm. The solid electrolyte includes: aeolian sand 55 wt%, portland cement 20 wt%, alumina fiber 3 wt%, sodium sulfate 10 wt%, and Na3PS4 10 wt%.

[0041] The preparation method of the energy storage battery is as follows:

[0042] S1 Prepare the positive electrode plate: Weigh activated carbon and polyvinylidene fluoride according to a mass ratio of 95:5. Add the activated carbon and polyvinylidene fluoride to NMP for blending. After high-speed stirring, a positive electrode slurry is formed. Then, the positive electrode slurry is evenly coated on aluminum foil and dried, rolled, and slit to obtain a positive electrode plate with an active layer thickness of 3 mm.

[0043] S2 Prepare the solid electrolyte slurry: Weigh aeolian sand, portland cement, alumina fiber, sodium sulfate, and Na3PS4 according to the ratio. Mix the portland cement, alumina fiber, sodium sulfate, and Na3PS4 and put them into a mixing container for dry mixing for 60 min to obtain a uniformly mixed mixture. Dissolve sodium sulfate in a certain amount of water to obtain a sodium salt solution with a concentration of 1 M. Add the mixture to the sodium salt solution and stir for 200 min until it is evenly dispersed to obtain a slurry.

[0044] S3 Prepare the battery: Place the positive electrode plate and the zinc plate at the front and back of the mold respectively, with the positive electrode active layer facing the zinc plate. Then pour the slurry into the mold, level it by vibration, and adjust the distance between the positive and negative electrode plates to 50 mm. Then place the vibrated and leveled mold in an environment with a temperature of 25 °C and a humidity of 50 ± 5% and let it stand for 20 h. Then place the mold in an environment with a humidity of 90 ± 5% for curing for 10 days to make the cement fully hydrated. Then place it at 80 °C for drying for 5 days and demold. Place the demolded product at 250 °C and let it stand for 5 h.

[0045] Test the battery. The voltage of the energy storage battery is 2.11 V, the specific energy is 24.4 Wh / Kg, the ionic conductivity is 3.5 mS / cm, and the capacity retention rate is 86% after being placed for 1000 h. After standardizing the battery quality, it is calculated that the capacity of the energy storage battery is about 24 Wh.

[0046] Example 3

[0047] An energy storage battery includes a positive electrode plate, a negative electrode plate, and a solid electrolyte. The negative electrode plate is an iron plate with a thickness of 5 mm. The solid electrolyte includes: aeolian sand 60 wt%, portland cement 20 wt%, aluminum silicate fiber 3 wt%, sodium nitrate 7 wt%, and Na 1.4 Al 0.4 Ti 1.6 (PO4)3 10 wt%,

[0048] The preparation method of the energy storage battery is as follows:

[0049] S1 Prepare the positive electrode plate: Weigh activated carbon and sodium carboxymethylcellulose according to a mass ratio of 93:7. Add the activated carbon and sodium carboxymethylcellulose to NMP for blending. After high-speed stirring, a positive electrode slurry is formed. Then, evenly coat the positive electrode slurry on the copper foil. After drying, rolling, and slitting, a positive electrode plate with an active layer thickness of 2 mm is obtained.

[0050] S2 Prepare the solid electrolyte slurry: Weigh aeolian sand, portland cement, aluminum silicate fiber, sodium nitrate, and Na 1.4 Al 0.4 Ti 1.6 (PO4)3; Mix aeolian sand, portland cement, aluminum silicate fiber, Na 1.4 Al 0.4 Ti 1.6 (PO4)3 and put them into a mixing container for dry mixing for 40 min to obtain a uniformly mixed mixture; Dissolve the sodium salt in a certain amount of water to obtain a sodium salt solution with a concentration of 0.7 M; Add the mixture to the sodium salt solution and stir for 100 min until it is uniformly dispersed to obtain a slurry.

[0051] S3 Prepare the battery: Place the positive electrode plate and the iron plate in front of and behind the mold respectively, with the positive electrode active layer facing the iron plate; Then pour the slurry into the mold, level it by vibration, and adjust the distance between the positive and negative electrode plates to 20 mm. Then place the leveled mold in an environment with a temperature of 25 °C and a humidity of 50 ± 5% and let it stand for 15 h; Then place the mold in an environment with a humidity of 90 ± 5% for 7 days to allow the cement to fully hydrate; Then place it at 70 °C and dry for 4 days and then demold; Place the demolded product at 200 °C and let it stand for 3 h.

[0052] Test the battery. The voltage of this energy storage battery is 1.81 V, the specific energy is 20.9 Wh / Kg, the ionic conductivity is 2.7 mS / cm, and the capacity retention rate after being placed for 1000 h is 81%. After standardizing the battery quality, it is calculated that the capacity of this energy storage battery is about 20 Wh.

[0053] Example 4

[0054] An energy storage battery includes a positive electrode plate, a negative electrode plate, and a solid electrolyte. The negative electrode plate is an iron plate with a thickness of 5 mm. The solid electrolyte includes: 50 wt% aeolian sand, 25 wt% portland cement, 5 wt% aluminum silicate fiber, 10 wt% sodium nitrate, and 5 wt% Na3PS4, 5 wt% NaFePO4.

[0055] The preparation method of the energy storage battery is as follows:

[0056] S1 Prepare the positive electrode plate: Weigh activated carbon and sodium carboxymethyl cellulose according to a mass ratio of 93:7. Add the activated carbon and sodium carboxymethyl cellulose to NMP for blending. After high-speed stirring, a positive electrode slurry is formed. Then, the positive electrode slurry is evenly coated on a copper foil, and after drying, rolling, and slitting, a positive electrode plate with an active layer thickness of 1 mm is obtained;

[0057] S2 Prepare the solid electrolyte slurry: Weigh aeolian sand, portland cement, aluminosilicate fiber, sodium nitrate, and Na3PS4, NaFePO4 according to a ratio. Mix the aeolian sand, portland cement, aluminosilicate fiber, Na3PS4, and NaFePO4 and put them into a mixing container for dry mixing for 40 min to obtain a uniformly mixed mixture. Dissolve the sodium salt in a certain amount of water to obtain a 1 M sodium salt solution. Add the mixture to the sodium salt solution and stir for 100 min until it is evenly dispersed to obtain a slurry;

[0058] S3 Prepare the battery: Place the positive electrode plate and an iron plate in front of and behind the mold respectively, with the positive electrode active layer facing the iron plate. Then pour the slurry into the mold, level it by vibration, and adjust the distance between the positive and negative electrode plates to 10 mm. Then place the vibrated and leveled mold in an environment with a temperature of 25 °C and a humidity of 50 ± 5% and let it stand for 15 h. Then place the mold in an environment with a humidity of 90 ± 5% for 7 days to allow the cement to fully hydrate. Then place it at 70 °C and dry for 4 days and then demold. Place the demolded product at 200 °C and let it stand for 3 h.

[0059] Test the battery. The voltage of this energy storage battery is 1.86 V, the specific energy is 21.8 Wh / Kg, the ionic conductivity is 3.1 mS / cm, and the capacity retention rate after being placed for 1000 h is 88%. After standardizing the battery quality, it is calculated that the capacity of this energy storage battery is about 21 Wh.

[0060] Comparative Example 1

[0061] An energy storage battery includes a positive electrode plate, a negative electrode plate, and a solid electrolyte. The negative electrode plate is an iron plate with a thickness of 5 mm. The solid electrolyte includes: 40 wt% aeolian sand, 50 wt% sulfoaluminate cement, and 10 wt% sodium chloride. The preparation method of the energy storage battery is as follows:

[0062] S1 Prepare the positive electrode plate: Weigh activated carbon and polyvinylidene fluoride according to a mass ratio of 95:5. Add the activated carbon and polyvinylidene fluoride to NMP for blending. After high-speed stirring, a positive electrode slurry is formed. Then, the positive electrode slurry is evenly coated on a copper foil, and after drying, rolling, and slitting, a positive electrode plate with an active layer thickness of 2 mm is obtained;

[0063] S2 Preparation of solid electrolyte slurry: Weigh aeolian sand, sulfoaluminate cement, and sodium chloride in proportion; mix the aeolian sand and sulfoaluminate cement and put them into a mixing container for dry mixing for 50 minutes to obtain a uniformly mixed mixture; dissolve sodium chloride in water to obtain a sodium salt solution with a concentration of 0.1 M; add the mixture to the sodium salt solution and stir for 60 minutes until uniformly dispersed to obtain the slurry;

[0064] S3 Preparation of the battery: Place the positive electrode plate and the iron plate in front of and behind the mold respectively, with the positive active layer facing the iron plate; then pour the slurry into the mold, level it by vibration, adjust the distance between the positive and negative electrode plates to 20 mm, and then place the vibration-leveled mold in an environment with a temperature of 25 °C and a humidity of 50 ± 5% and let it stand for 10 hours; then place the mold in an environment with a humidity of 90 ± 5% for 10 days to allow the cement to fully hydrate; then place it at 80 °C and dry for 4 days and then demold; place the demolded product at 180 °C and let it stand for 5 hours.

[0065] Test the battery. The voltage of this energy storage battery is 1.74 V, the specific energy is 13.4 Wh / Kg, the ionic conductivity is 0.7 mS / cm, and the capacity retention rate is 48% after being placed for 1000 h. After standardizing the battery quality, it is calculated that the capacity of this energy storage battery is about 13 Wh. However, during long-term use, especially when stored at low or high temperatures for a long time, the battery capacity decays rapidly, and cracks easily appear in the electrolyte during long-term operation, resulting in problems with battery stability.

[0066] Comparative Example 2

[0067] An energy storage battery includes a positive electrode plate, a negative electrode plate, and a solid electrolyte. The negative electrode plate is an iron plate with a thickness of 5 mm. The solid electrolyte includes: 70 wt% aeolian sand, 16 wt% silicate cement, 10 wt% sodium nitrate, and 4 wt% Na 1.4 Al 0.4 Ti 1.6 (PO4)3;

[0068] The preparation method of the energy storage battery is as follows:

[0069] S1 Preparation of the positive electrode plate: Weigh activated carbon and sodium carboxymethylcellulose in a mass ratio of 93:7, add the activated carbon and sodium carboxymethylcellulose to NMP for blending, form a positive electrode slurry after high-speed stirring, and then uniformly coat the positive electrode slurry on the copper foil. After drying, rolling, and slitting, a positive electrode plate with an active layer thickness of 2 mm is prepared;

[0070] S2 Preparation of solid electrolyte slurry: Weigh aeolian sand, silicate cement, aluminum silicate fiber, sodium nitrate, and Na 1.4 Al 0.4 Ti 1.6(PO4)3; Mix aeolian sand, portland cement, aluminosilicate fiber, and Na 1.4 Al 0.4 Ti 1.6 (PO4)3 in a mixing container and perform dry mixing for 40 minutes to obtain a uniformly mixed mixture; dissolve the sodium salt in a certain amount of water to obtain a sodium salt solution with a concentration of 2M; add the mixture to the sodium salt solution and stir for 100 minutes until uniformly dispersed to obtain a slurry;

[0071] S3 Prepare the battery: Place the positive electrode plate and the iron plate in front of and behind the mold respectively, with the positive active layer facing the iron plate; then pour the slurry into the mold, level it by vibration, and adjust the distance between the positive and negative electrode plates to 20 mm. After that, place the vibrated and leveled mold in an environment with a temperature of 25°C and a humidity of 50±5% and let it stand for 15 hours; then place the mold in an environment with a humidity of 90±5% and cure for 7 days to allow the cement to fully hydrate; then place it at 70°C and dry for 4 days and then demold; place the demolded product at 200°C and let it stand for 3 hours.

[0072] Test the battery. The voltage of this energy storage battery is 1.77V, the specific energy is 15.3 Wh / Kg, the ionic conductivity is 1.2 mS / cm, and the capacity retention rate after 1000 hours of placement is 51%. After standardizing the battery quality, it is calculated that the capacity of this energy storage battery is about 15 Wh.

[0073] Comparative Example 3

[0074] An energy storage battery includes a positive electrode plate, a negative electrode plate, and a solid electrolyte. The negative electrode plate is an iron plate with a thickness of 5 mm. The solid electrolyte includes: 75 wt% of portland cement, 5 wt% of aluminosilicate fiber, 10 wt% of sodium nitrate, 5 wt% of Na3PS4, and 5 wt% of NaFePO4.

[0075] The preparation method of the energy storage battery is as follows: S1 Prepare the positive electrode plate: Weigh activated carbon and sodium carboxymethylcellulose according to a mass ratio of 93:7. Add the activated carbon and sodium carboxymethylcellulose to NMP for blending. After high-speed stirring, form a positive electrode slurry. Then uniformly coat the positive electrode slurry on the copper foil, and after drying, rolling, and slitting, obtain a positive electrode plate with an active layer thickness of 1 mm.

[0076] S2 Prepare the solid electrolyte slurry: Weigh portland cement, aluminosilicate fiber, sodium nitrate, Na3PS4, and NaFePO4 according to the ratio; mix the portland cement, aluminosilicate fiber, Na3PS4, and NaFePO4 in a mixing container and perform dry mixing for 40 minutes to obtain a uniformly mixed mixture; dissolve the sodium salt in a certain amount of water to obtain a sodium salt solution with a concentration of 1M; add the mixture to the sodium salt solution and stir for 100 minutes until uniformly dispersed to obtain a slurry;

[0077] S3 Prepare the battery: Place the positive electrode plate and the iron plate in front of and behind the mold respectively, with the positive active layer facing the iron plate; then pour the slurry into the mold, level it by vibration, and adjust the distance between the positive and negative electrode plates to 10 mm. After that, place the leveled mold in an environment with a temperature of 25°C and a humidity of 50±5% and let it stand for 15 h; then place the mold in an environment with a humidity of 90±5% for 7 days to allow the cement to fully hydrate; then place it at 70°C and dry for 4 days and then demold; place the demolded product at 200°C and let it stand for 3 h.

[0078] Test the battery. The voltage of this energy storage battery is 1.79 V, the specific energy is 8.6 Wh / Kg, the ionic conductivity is 0.4 mS / cm, and the capacity retention rate is 36% after being placed for 1000 h. After standardizing the battery quality, it is calculated that the capacity of this energy storage battery is about 8 Wh.

[0079] Comparative Example 4

[0080] An energy storage battery includes a positive electrode plate, a negative electrode plate, and a solid electrolyte. The negative electrode plate is an iron plate with a thickness of 5 mm. The solid electrolyte includes: 50 wt% river sand, 25 wt% portland cement, 5 wt% aluminum silicate fiber, 10 wt% sodium nitrate, 5 wt% Na3PS4, and 5 wt% NaFePO4. The particle sizes of the river sand are different, and the average particle size is 0.5 - 3 mm.

[0081] The preparation method of the energy storage battery is as follows:

[0082] S1 Prepare the positive electrode plate: Weigh activated carbon and sodium carboxymethylcellulose according to a mass ratio of 93:7. Add the activated carbon and sodium carboxymethylcellulose to NMP for blending. After high-speed stirring, a positive electrode slurry is formed. Then evenly coat the positive electrode slurry on the copper foil, and after drying, rolling, and slitting, a positive electrode plate with an active layer thickness of 1 mm is prepared.

[0083] S2 Prepare the solid electrolyte slurry: Weigh river sand, portland cement, aluminum silicate fiber, sodium nitrate, Na3PS4, and NaFePO4 according to the ratio; mix the river sand, portland cement, aluminum silicate fiber, Na3PS4, and NaFePO4 and put them into a mixing container for dry mixing for 40 min to obtain a uniformly mixed mixture; dissolve the sodium salt in a certain amount of water to obtain a sodium salt solution with a concentration of 1 M; add the mixture to the sodium salt solution and stir for 100 min until it is uniformly dispersed to obtain a slurry.

[0084] S3 Battery Preparation: Place the positive electrode sheet and the iron plate in front of and behind the mold respectively, with the positive active layer facing the iron plate. Then pour the slurry into the mold, level it by vibration, and adjust the distance between the positive and negative electrode sheets to 10 mm. After that, place the leveled mold in an environment with a temperature of 25°C and a humidity of 50±5% and let it stand for 15 h. Then place the mold in an environment with a humidity of 90±5% for 7 days to allow the cement to fully hydrate. Then dry it at 70°C for 4 days and demold. Place the demolded product at 200°C and let it stand for 3 h.

[0085] Test the battery. The voltage of this energy storage battery is 1.86 V, the specific energy is 11.8 Wh / Kg, the ionic conductivity is 1.8 mS / cm, and the capacity retention rate is 76% after being placed for 1000 h. After standardizing the battery quality, it is calculated that the capacity of this energy storage battery is about 11 Wh.

[0086] It can be seen from the above test data that the solid electrolyte energy storage battery obtained by using aeolian sand in combination with cement, inorganic insulating fiber, sodium salt and additives in the present invention has a relatively high specific energy and ionic conductivity, and the battery has good cycle stability. It can be seen that aeolian sand can be used as an electrolyte filler in energy storage batteries. When using inorganic insulating fiber, it can effectively improve the stability of the electrolyte, and the electrolyte does not show cracks or peeling during long-term use. However, the dosage of aeolian sand cannot be too large, as excessive addition will also affect the stability of the solid electrolyte layer. The reason may be that too much filler easily causes solid phase stratification or sedimentation and precipitation during charge and discharge. It can be seen from the examples and comparative examples 1-2 that aeolian sand can be used in energy storage batteries, which will not deteriorate the battery performance, and can better control the battery cost, with good economic value. If it can be popularized, it can largely solve the harm caused by desertification and truly turn waste into treasure. It can be seen from comparative example 3 that the performance of the cement battery without using aeolian sand decreases significantly. After analysis, it may be that the cement content in the electrolyte without filler is relatively high and there is no filler, the viscosity of the cement slurry is relatively high, and the additives in it are difficult to be evenly dispersed, greatly reducing the internal ion transport channels and affecting ion transport. It can also be seen from comparative example 4 of river sand that the cement and inorganic fiber system using aeolian sand has a relatively high specific energy and ionic conductivity. The analysis may be that a specific system generates relatively sufficient internal pores, providing rich channels for ion transport.

[0087] The above has introduced a storage battery and its preparation method in detail. The above content is a further detailed description of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, its architecture form can be flexible and changeable, and a series of products can be derived. Just making several simple deductions or substitutions should be regarded as belonging to the patent protection scope determined by the claims submitted for the present invention.

Claims

1. An energy storage battery, comprising a positive electrode sheet, a negative electrode sheet and a solid electrolyte separating the positive electrode sheet and the negative electrode sheet, characterized in that: The solid electrolyte comprises: aeolian sand, cement, inorganic insulating fiber, sodium salt and additives, wherein the additive is selected from Na3Zr2Si2PO 12 、Na3Zr2Si3P3O 14 、Li7La3Zr2O 12 , Li 6.4 Ln3Z 1.4 Ta 0.6 O 12 , NaFePO4, Na3PS4, Na3PSe4, Na 10 SnP2S 12 、Na 1.4 Al 0.4 Ti 1.6 (PO4)3 and Na 0.5 Bi 0.5 At least one of TiO3.

2. The energy storage battery according to claim 1, characterized in that: The positive electrode plate includes a positive electrode collector and a positive electrode active layer attached to the positive electrode collector, the positive electrode active layer includes 90wt% to 95wt% of activated carbon and 5wt% to 10wt% of a binder, the binder is selected from one of polytetrafluoroethylene, polyvinylidene fluoride, and sodium carboxymethyl cellulose, the thickness of the positive electrode active layer is 0.5 to 3mm, and the positive electrode collector is copper foil or aluminum foil.

3. The energy storage battery according to claim 1, characterized in that: The negative electrode plate is a metal plate, the metal is selected from one of iron and zinc, and the thickness of the metal plate is 1 to 10 mm.

4. The energy storage battery according to claim 1, characterized in that: The inorganic insulating fiber is selected from at least one of alkali-free glass fiber, alumina fiber, basalt fiber, mullite fiber, and aluminum silicate fiber, and the cement is one of sulphoaluminate cement and silicate cement.

5. The energy storage battery according to claim 1, characterized in that: The mass fractions of the components in the solid electrolyte are 40-60wt% of aeolian sand, 20-40wt% of cement, 1-5wt% of inorganic insulating fiber, 1-10wt% of sodium salt, and 5-10wt% of additives.

6. The energy storage battery according to claim 1, characterized in that: The positive electrode sheet preparation method is as follows: activated carbon and a binder are weighed at a mass ratio of 90-95:5-10, the activated carbon and the binder are added into an organic solvent NMP and mixed, and a positive electrode slurry is formed after high-speed stirring, and then the positive electrode slurry is evenly coated on a positive electrode collector, and a positive electrode sheet is obtained after drying, rolling, and slitting.

7. The energy storage battery according to claim 1, characterized in that: The solid electrolyte has a thickness of 5 to 50 mm, and the sodium salt is one of sodium nitrate and sodium sulfate. The preparation method thereof is as follows: 1) Weigh aeolian sand, cement, inorganic insulating fiber, sodium salt and additives in proportion; 2) mixing aeolian sand, cement, inorganic insulating fiber and additives, and placing them in a mixing container for dry mixing for 10 to 60 minutes to obtain a uniformly mixed mixture; dissolving sodium salt in water to obtain a sodium salt solution with a concentration of 0.5 to 1 M; 3) Add the mixture obtained in step 2) into the sodium salt solution and stir for 60 to 200 minutes until the mixture is evenly dispersed to obtain a slurry. Pour the slurry into a mold, smooth it with vibration, solidify it, and heat treat it.

8. The energy storage battery according to claim 7, characterized in that: The curing is specifically as follows: placing the vibrated and smoothed mold in an environment with a temperature of 25°C and a humidity of 50±5% for 10 to 20 hours; then placing the mold in an environment with a humidity of 90±5% for curing for 5 to 10 days to allow the cement to be completely hydrated; then placing it at 60 to 80°C for drying for 2 to 5 days and then demolding; the heat treatment is placing the demolded product at 150 to 250°C for 1 to 5 hours.

9. A method for preparing an energy storage battery according to any one of claims 1 to 8, wherein the energy storage battery comprises a positive electrode sheet, a negative electrode sheet, and a solid electrolyte located between the positive electrode sheet and the negative electrode sheet and separating the two, characterized in that: The steps include: S1: preparing positive electrode sheets: weighing activated carbon and a binder in a mass ratio of 90-95:5-10, adding the activated carbon and the binder into NMP and mixing them, stirring at a high speed to form a positive electrode slurry, then evenly coating the positive electrode slurry on the positive electrode collector, drying, rolling, and cutting to obtain positive electrode sheets; S2 prepares solid electrolyte slurry: weigh aeolian sand, cement, inorganic insulating fiber, sodium salt and additives in proportion; mix aeolian sand, cement, inorganic insulating fiber and additives and put them into a mixing container for dry mixing for 10 to 60 minutes to obtain a uniform mixture; dissolve sodium salt in water to obtain a sodium salt solution with a concentration of 0.5 to 1M; add the mixture to the sodium salt solution and stir for 60 to 200 minutes until it is evenly dispersed to obtain a slurry; S3 battery preparation: place the positive electrode sheet and the negative electrode sheet in front and behind the mold respectively, with the positive electrode active layer facing the negative electrode sheet; then pour the slurry into the mold, smooth it with vibration, adjust the distance between the positive and negative electrode sheets, and then solidify and heat treat it.

10. The preparation method according to claim 9, characterized in that: The curing is specifically as follows: placing the vibrated and smoothed mold in an environment with a temperature of 25°C and a humidity of 50±5% for 10 to 20 hours; then placing the mold in an environment with a humidity of 90±5% for curing for 5 to 10 days to allow the cement to be completely hydrated; then placing it at 60 to 80°C for drying for 2 to 5 days and then demolding; the heat treatment is placing the demolded product at 150 to 250°C for 1 to 5 hours.