Sodium-chloride batteries with highly reactive interfaces

Abstract

The present invention relates to a sodium-chloride battery with a high reaction interface, which comprises the following parts: a conductive shell with an open end, wherein a plurality of electrolyte ceramic tubes are arranged in an array inside the conductive shell; a conductive cover for sealing the open end connected to the conductive shell; an insulating ceramic substrate arranged between the conductive shell and the conductive cover for carrying the plurality of electrolyte ceramic tubes, wherein the opening of each electrolyte ceramic tube is connected to a corresponding through-hole in the insulating ceramic substrate; each electrolyte ceramic tube contains a positive electrode material and a current collecting electrode, and the current collecting electrode passes through the through-hole of the insulating ceramic substrate and is connected to the conductive cover; and a conductive material is filled between the conductive shell and each electrolyte ceramic tube.

Description

Technical Field

[0001] The invention relates to a battery structure, in particular to a sodium-chloride battery with a high reaction interface, belonging to the field of batteries. Background Art

[0002] Sodium-chloride batteries are developed from Na-S batteries. In addition to having similar advantages as Na-S batteries, such as high theoretical specific capacity, good cycle performance, long life, and no self-discharge, their safety performance is far superior to that of Na-S batteries. 12 Damage to the electrolyte membrane, resulting in a short circuit between the positive and negative electrodes, occurs in a low-current mode, without releasing significant heat. Consequently, safety hazards such as combustion or even explosions that can occur when a Na-S battery short-circuit occurs are avoided. Furthermore, since the sodium-chloride battery is in a discharged state, assembly requires no Na, reducing operational complexity and cost.

[0003] Based on these advantages, sodium-chloride batteries are gaining increasing attention, making them an important option for electric vehicles and large-capacity energy storage. However, the low power density of sodium-chloride batteries limits their application as a power source for electric vehicles.

[0004] To increase the power density of sodium-chloride batteries, researchers have conducted extensive and fruitful research, primarily focusing on increasing the reaction area of the battery's electrochemical reactions and shortening the ion diffusion path. The electrolyte structure has also evolved from the original cylindrical tubular structure to a four-leaf clover-shaped tubular structure, and the battery's power density has gradually increased, for example, from 80W / kg to 115W / kg.

[0005] For example, Patent 1 (Chinese Patent Publication No. CN101752614A) describes a high-energy-density sodium-nickel chloride single cell and its battery pack. The disclosure discloses that the cross-section of the electrolyte ceramic tube in the sodium-nickel chloride single cell is circular or cross-shaped, similar to the aforementioned cylindrical and four-leaf clover-shaped electrolyte ceramic tubes.

[0006] As mentioned above, in the prior art, sodium-chloride batteries have gradually improved their power density by evolving the electrolyte structure from a cylindrical tubular structure to a four-leaf cloverleaf structure. However, both cylindrical and four-leaf cloverleaf ceramic electrolyte tubes offer limited improvements in energy and power density, and the capacity of individual cells is limited. Efforts are currently underway to develop high-capacity sodium-chloride batteries with even higher energy and power densities. Summary of the Invention

[0007] In view of the above problems, the object of the present invention is to provide a sodium-chloride battery with a high reaction interface, so that the sodium-chloride battery can have higher energy density and power density and facilitate large-capacity design.

[0008] To this end, the present invention provides a sodium-chloride battery with a high reaction interface, which is composed of the following parts:

[0009] A conductive shell having an open end, wherein the conductive shell has a plurality of electrolyte ceramic tubes distributed in an array;

[0010] A conductive cover portion, used for closing the open end connected to the conductive shell;

[0011] An insulating ceramic substrate is provided between the conductive shell and the conductive cover for supporting a plurality of electrolyte ceramic tubes, wherein the opening of each electrolyte ceramic tube is connected to the corresponding through portion in the insulating ceramic substrate. Figure 1 21 is the through part);

[0012] Each electrolyte ceramic tube includes a positive electrode material and a current collecting electrode, and the current collecting electrode passes through the through-hole of the insulating ceramic substrate and is connected to the conductive cover;

[0013] A conductive material is filled between the conductive housing and each electrolyte ceramic tube. The conductive material is selected from at least one of carbon, graphite, and metal. The carbon, graphite, and metal may be in the form of particles, fibers, powder, or sheets, and is used to connect the electrolyte ceramic tube and the conductive housing.

[0014] The sodium-chloride battery with a high-reaction interface in the present invention is a multi-tubular structure. While maintaining the same volume of the electrolyte ceramic tubes, smaller-caliber ceramic tubes are used in a multi-tubular layout. This effectively increases the surface area of the electrolyte ceramic tubes, thereby increasing the diffusion channels for sodium ions and the area for electrochemical reactions, while shortening the sodium ion diffusion path. This multi-tubular structure allows for higher energy and power densities, and allows for the design of larger-capacity single-cell batteries.

[0015] Preferably, the electrolyte ceramic tube is beta-Al2O3, or a sodium ion conductor (such as Na3Zr2Si2PO 12 ); the insulating ceramic substrate is alpha-Al2O3 ceramic. Using beta-Al2O3 ceramic tubes as the solid electrolyte for sodium-chloride batteries can function as both a separator and an electrolyte, while exhibiting high ionic conductivity. Furthermore, using alpha-Al2O3 ceramic as the insulating ceramic substrate offers high resistivity and excellent insulation properties.

[0016] Preferably, the number of the electrolyte ceramic tubes is 3 to 9. That is, the array of multiple electrolyte ceramic tubes can be a multi-tube array structure composed of any combination of three tubes, four tubes, five tubes, and six tubes. As the number of tubes increases, the surface area of the electrolyte ceramic tubes can be further increased under the premise of the same volume.

[0017] Preferably, the conductive cover is provided with a tab; the conductive shell includes a shell and a bottom end cover.

[0018] Preferably, the through portion in the insulating ceramic substrate includes an upper through hole and a lower through hole, and the diameter of the lower through hole is smaller than the outer diameter of the electrolyte ceramic tube and smaller than the diameter of the upper through hole, forming a slot.

[0019] Furthermore, preferably, an insulating sealing medium is provided between the upper through hole in the insulating ceramic substrate and the electrolyte ceramic tube; preferably, the insulating sealing medium is sealing glass, ceramic sealant or sealant.

[0020] Preferably, a first metal ring is provided between the insulating ceramic substrate and the conductive housing, and / or a second metal ring is provided between the insulating ceramic substrate and the conductive cover. Preferably, the first and second metal rings are made of Kovar, stainless steel, nickel, or an aluminum alloy. According to the present invention, by providing the first and second metal rings between the insulating ceramic substrate and the housing shell and / or between the insulating ceramic substrate and the cover, the insulating ceramic substrate can be effectively positioned and connected between the housing shell and the cover. The metal rings can be made of Kovar, stainless steel, nickel, or an aluminum alloy to facilitate connection between the battery housing and the cover.

[0021] Preferably, an insulating sealing medium is provided between the insulating ceramic substrate and the metal ring. Preferably, the insulating sealing medium is sealing glass, ceramic sealant, or sealant, which can provide good sealing properties. The sealing glass can be borosilicate glass, CG294 glass, or the like; the ceramic sealant can be CERAMABOND 552-VFG from Fuel Cell Materials (USA) or JL-767A from Dongguan Juli Adhesive Products Co., Ltd.; and the sealant can be a single-component neutral sealant or a non-collapse silicone sealant, such as JD-9766 from Dongguan Jiudian Adhesive Co., Ltd. or GL-1280 from Xiamen Yuanchuang Special Glass Co., Ltd.

[0022] According to the present invention, by arranging an insulating sealing medium between the insulating ceramic substrate and the metal ring and / or between the insulating ceramic substrate and multiple electrolyte ceramic tubes, the leakage of the positive electrode material in the multiple electrolyte ceramic tubes can be effectively prevented. At the same time, the insulating sealing medium can also realize the connection between the insulating ceramic substrate and the metal ring with excellent connection strength.

[0023] Preferably, the positive electrode material is a mixture containing at least one of Ni and Fe, NaCl, and NaAlCl4. When using the above positive electrode materials, the metal in the conductive material is preferably not Na. This can prevent leakage of Na after the electrolyte ceramic tube ruptures, thereby improving the safety of the battery. In addition, the positive electrode material also contains one or more of C, Cu, Co, Zn, FeS, NaF, NaBr, and NaI, and has good ionic and electronic conductivity.

[0024] Preferably, the current collecting electrode is a copper conductor with nickel plating on the surface, a pure nickel conductor, an Fe conductor or a C material conductor, etc. In the present invention, using a copper conductor with nickel plating on the surface as the current collecting electrode can increase the oxidation resistance and corrosion resistance of the current collecting electrode and increase the conductivity.

[0025] Preferably, the conductive cover and the conductive shell may be made of stainless steel or aluminum alloy, etc., which can improve their conductivity.

[0026] Preferably, the conductive shell is in a shape of a round tube, a square tube or other shapes, and can be designed according to needs.

[0027] Preferably, the size (outer diameter or side length) of the electrolyte ceramic tube is 15-60 mm, and the wall thickness is 0.5-3 mm; preferably, the size (outer diameter or side length) of the electrolyte ceramic tube is 20-40 mm, and the wall thickness is 1-1.5 mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description with reference to the accompanying drawings:

[0029] Figure 1 A longitudinal sectional view schematically showing the structure of a sodium-chloride battery according to one embodiment of the present invention;

[0030] Figure 2 A transverse cross-sectional view of an embodiment of a sodium-chloride battery according to the present invention schematically showing a three-tube arrangement of electrolyte ceramic tubes;

[0031] Figure 3 A transverse cross-sectional view of an embodiment of a sodium-chloride battery according to the present invention schematically showing a four-tube arrangement of electrolyte ceramic tubes;

[0032] Figure 4 A transverse cross-sectional view of an embodiment of a sodium-chloride battery according to the present invention schematically showing a five-tube arrangement of electrolyte ceramic tubes;

[0033] Figure 5A transverse cross-sectional view of an embodiment of a sodium-chloride battery according to the present invention schematically showing six electrolyte ceramic tubes arranged;

[0034] Figure 6 The figure is a transverse cross-sectional view of an embodiment of a sodium-chloride battery according to the present invention, schematically showing nine electrolyte ceramic tubes arranged in an array. DETAILED DESCRIPTION

[0035] The sodium-chloride battery with a high reaction interface of the present invention is further described with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of protection of the present invention.

[0036] Specifically, Figure 1 The structure of a sodium-chloride battery according to one embodiment of the present invention is schematically shown. Figure 1 As shown, the sodium-chloride battery with a highly reactive interface includes a conductive outer shell 11 (referred to as the conductive outer shell) and a conductive cover 8 (referred to as the conductive cover). In this embodiment, the conductive outer shell 11 and the cover 8 can be made of stainless steel or aluminum alloy, but the present invention is not limited thereto and can also be made of other conductive materials. The conductive outer shell 11 preferably includes a housing 7 and a bottom end cap 10.

[0037] Furthermore, the conductive housing 11 is welded to the bottom end cap 10, and the cap 8 seals the open end of the housing 11 via the insulating ceramic substrate 2. In this embodiment, the insulating ceramic substrate 2 may be made of alpha-Al2O3 ceramic with high resistivity and good insulation properties, but the present invention is not limited thereto.

[0038] In addition, the sodium-chloride battery of the present invention further includes a plurality of electrolyte ceramic tubes 1 arranged in an array within the housing 11. In this embodiment, the electrolyte ceramic tubes 1 may be beta-Al2O3 ceramic tubes, which can serve as both a diaphragm and an electrolyte and have high ionic conductivity, but the present invention is not limited thereto. The opening of each electrolyte ceramic tube 1 is connected to the plurality of through-holes 21 of the corresponding insulating ceramic substrate 2. Each electrolyte ceramic tube 1 is filled with a positive electrode material and a current collecting electrode 5. The current collecting electrode 5 extends through the through-holes 21 of the insulating ceramic substrate 2 and is connected to the cover 8 for extraction.

[0039] In this embodiment, the positive electrode material can be a mixture of Ni, NaCl, and NaAlCl4, or a mixture of Fe, NaCl, and NaAlCl4. Furthermore, C, FeS, NaF, and other materials with good ionic and electronic conductivity can also be added. The current collecting electrode 5 can be a copper conductor with a nickel-plated surface, thereby increasing its oxidation resistance, corrosion resistance, and conductivity.

[0040] More specifically, in Figure 1 In the illustrated embodiment, each through-portion 21 of the insulating ceramic substrate 2 can be provided with a slot 22 at one end thereof, proximate to the housing 11. Multiple dielectric ceramic tubes 1 can be mounted in each slot 22, with the opening of each dielectric ceramic tube 1 communicating with the corresponding through-portion 21 of the insulating ceramic substrate 2. Furthermore, the cover 8 can be provided with a tab 9 through which the current collecting electrodes 5 within each dielectric ceramic tube 1 can be led out. The tab 9 can also be made of a conductive material such as stainless steel or an aluminum alloy.

[0041] like Figure 1 As shown, the sodium-chloride battery of the present invention may further include a first metal ring 3 disposed between the insulating ceramic substrate 2 and the outer shell 11, and / or a second metal ring 4 disposed between the insulating ceramic substrate 2 and the cover 8. The provision of the first metal ring 3 and the second metal ring 4 effectively positions and connects the insulating ceramic substrate 2 between the outer shell 11 and the cover 8, facilitating industrial production of the battery. In one embodiment of the present invention, both the first metal ring 3 and the second metal ring 4 can be made of Kovar alloy, stainless steel, Ni, or an aluminum alloy.

[0042] In an alternative embodiment, the outer diameter of the upper portion of the insulating ceramic base 2 is less than the inner diameter of the first metal ring 3 and less than the inner diameter of the outer shell. The outer diameter of the middle portion of the insulating ceramic base 2 is equal to the outer diameter of the outer shell. The outer diameter of the lower portion of the insulating ceramic base 2 is less than the inner diameter of the second metal ring 4 and less than the inner diameter of the cover. The cross-section of the second metal ring 4 is preferably L-shaped, which increases the welding area with the cover.

[0043] In addition, in the present invention, an insulating sealing medium 6 can be provided between the insulating ceramic substrate 2 and the first metal ring 3 and the second metal ring 4 and / or between the insulating ceramic substrate 2 and the multiple electrolyte ceramic tubes 1. Between the insulating ceramic substrate 2 and the multiple electrolyte ceramic tubes 1, the positive electrode material in the multiple electrolyte ceramic tubes 1 can be effectively prevented from leaking into the chamber between the conductive shell and each electrolyte ceramic tube and the external environment. An insulating sealing medium is provided between the insulating ceramic substrate 2 and the first metal ring 3 and the second metal ring 4, which can achieve effective connection between the shell of the conductive shell and the insulating ceramic substrate, and between the insulating ceramic substrate and the conductive cover, solving the problem that the conductive cover or the conductive shell is mismatched and difficult to connect with the insulating ceramic substrate. In one embodiment of the present invention, the insulating sealing medium 6 can be sealing glass, ceramic sealant or sealant, etc.

[0044] In an optional embodiment, if Figure 1As shown, the insulating sealing medium can be arranged between the insulating ceramic substrate and the electrolyte ceramic tube. In addition, the arrangement of the insulating sealing medium between the insulating ceramic substrate 2 and the first metal ring 3 and the second metal ring 4 can be adjusted accordingly according to the size of the metal rings, generally the metal rings are close to the side and / or bottom of the insulating ceramic substrate. Moreover, the size (diameter or side length) of the shell in the present invention can generally be 50 to 250 mm. The diameter (or side length) of the ceramic tube is distributed between 15 mm and 60 mm. If the diameter or side length of the ceramic tube is too large, its performance improvement is not obvious; if the outer diameter or side length of the ceramic tube is too small, in addition to increasing the production and assembly costs, it also limits the improvement of the battery capacity, but reduces its energy density.

[0045] The full-cell reaction of a sodium-chloride battery (using a sodium-nickel chloride battery as an example) is: NiCl2 + 2Na → Ni + 2NaCl. During normal charging, the sodium chloride in the positive electrode decomposes into sodium ions and chloride ions at a certain voltage. The sodium ions travel through the beta-Al2O3 ceramic electrolyte to the negative electrode, where they combine with electrons from the external circuit to form a sodium negative electrode. Simultaneously, the chloride ions react with the nickel to form nickel chloride, releasing electrons to the external circuit. During normal discharge, the sodium ions return through the beta-Al2O3 ceramic electrolyte to undergo the reverse process. Furthermore, since the sodium-chloride battery is in the discharged state, the assembly process is sodium-free, reducing operational complexity and saving costs.

[0046] in addition, Figures 2 to 5 Transverse cross-sectional views of various embodiments of sodium-chloride batteries according to the present invention are shown, each having a different number of electrolyte ceramic tube arrays.

[0047] like Figures 2 to 5 As shown, the multiple electrolyte ceramic tubes can be a multi-tube structure composed of three tubes, four tubes, five tubes and six tubes distributed in an array. As the number of tubes increases, the surface area of the electrolyte ceramic tubes can be further increased under the premise of the same volume. Figures 2 to 5 As shown, the shape of the shell can be a round tube or a square tube.

[0048] Specifically, Figure 2 The embodiment shows that the outer shell is in the shape of a circular tube and the electrolyte ceramic tubes are arranged in a three-tube array. Figure 3 (a) shows an embodiment in which the housing is a circular tube and the electrolyte ceramic tubes are arranged in a four-tube array; Figure 3 Middle (b) shows an embodiment in which the outer shell is in the shape of a square tube and the electrolyte ceramic tubes are distributed in a four-tube array. Figure 4 (a) shows an embodiment in which the housing is a circular tube and the electrolyte ceramic tubes are arranged in a five-tube array; Figure 4 Middle (b) shows an embodiment in which the outer shell is in the shape of a square tube and the electrolyte ceramic tubes are arranged in a five-tube array. Figure 5(a) shows an embodiment in which the housing is a circular tube and the electrolyte ceramic tubes are arranged in an array of six tubes; Figure 6 Middle (b) shows an embodiment in which the outer shell is in a square tube shape and the electrolyte ceramic tubes are distributed in a six-tube array.

[0049] Those skilled in the art may select the shape of the shell and / or the number and / or size of the electrolyte ceramic tubes according to actual needs, such as the requirements for the energy density and power density of the battery, or from the perspective of manufacturing economy.

[0050] The following examples are further given to illustrate the present invention in detail. It should also be understood that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention all fall within the scope of protection of the present invention. The specific process parameters and the like in the following examples are only examples within a suitable range, that is, those skilled in the art can make selections within a suitable range through the description herein, and are not limited to the specific numerical values exemplified below.

[0051] Comparative Example 1:

[0052] The volume of positive electrode material that can be accommodated by a single beta-Al2O3 ceramic tube with an inner diameter of 50mm, a wall thickness of 1.5mm, and a length of 240mm (excluding the length of the hemispherical part) is: V 50 =2 / 3πr 3 +πr 2 h=2 / 3π×(5 / 2) 3 +π(5 / 2) 2 ×24=504(cm 3 ), the surface area of the ceramic tube is: S 50 =2πr 2 +2πrh=2π×(5 / 2) 2 +2π×(5 / 2)×24=416(cm 2 The beta-Al2O3 ceramic tube weighs 209g; 504cm 3 The space can accommodate a composite positive electrode weighing about 1200g, a battery capacity of 120Ah, and a battery energy of 310Wh. The battery's specific energy is 220Wh / kg (based on the weight of the ceramic tube and the composite positive electrode), and the battery's specific power is 85W / L (based on 504cm 3 effective volume).

[0053] Comparative Example 2:

[0054] The volume of the positive electrode material that can be accommodated by a four-leaf clover-shaped beta-Al2O3 ceramic tube with an inner diameter of 20.5mm, a wall thickness of 1.5mm, and a length of 250mm is: V = (16 + π) r 2 h=(16+π)×(2.05 / 2) 2 ×25=503(cm 3 ), the surface area of the ceramic tube is: S = 8πrh = 8π×2.05 / 2×25 = 644 (cm 2 The beta-Al2O3 ceramic tube weighs 513g; 503cm 3 The space can accommodate a composite positive electrode weighing about 1200g, a battery capacity of 120Ah, and a battery energy of 310Wh. The battery's specific energy is 181Wh / kg (based on the weight of the ceramic tube and the composite positive electrode), and the battery's specific power is 132W / L (based on 503cm 3 effective volume).

[0055] Embodiments of the present invention:

[0056] like Figures 2 to 6 As shown in FIG. 1 , the high reaction interface sodium-chloride battery of the present invention adopts a multi-tube layout. The ceramic tubes can be a combination of three, four, five, six, nine, etc., wherein the small circle represents the beta-Al2O3 electrolyte ceramic tube and the outer large circle represents the battery shell. In the combination of four or more electrolyte ceramic tubes, the shell can also be square, such as Figure 3 -5 is shown in the box outside the small circle.

[0057] Taking the four-tube layout as an example, assuming that the inner diameter of each beta-Al2O3 electrolyte ceramic tube is 25mm and the length is 250mm (excluding the length of the hemispherical part), the volume of the positive electrode material that can be accommodated by the four electrolyte ceramic tubes is: V 25 =4×(2 / 3πr 3 +πr 2 h)=4×[2 / 3π×(2.5 / 2) 3 +π(2.5 / 2) 2 × 25]=507(cm 3 ), the total surface area of the four electrolyte ceramic tubes is: S 25 =4×(2πr 2 +2πrh)=4×[2π×(2.5 / 2) 2 +2π×(2.5 / 2)×25]=824(cm 2 The beta-Al2O3 ceramic tube weighs 427g; 507cm 3The space can accommodate a composite positive electrode weighing about 1200g, a battery capacity of 120Ah, and a battery energy of 310Wh. The battery's specific energy is 190Wh / kg (based on the weight of the ceramic tube and the composite positive electrode), and the battery's specific power is 170W / L (based on 507cm 3 effective volume).

[0058] Compared with Comparative Example 1 and Comparative Example 2, it can be seen that under the premise of equal volume of positive electrode material, when a combination of four small tubes with an inner diameter of 25 mm is used, the total surface area S 25 824cm 2 , is a single ceramic tube S with an inner diameter of 50mm 50 2 times (416cm 2 ), which is much larger than the surface area of a four-leaf clover-shaped ceramic tube of equal volume (644 cm 2 ), the specific power increased from 132W / L to 170W / L, and the specific energy increased from 181Wh / kg to 190Wh / kg. This shows that the four-tube battery structure has a larger electrochemical reaction area and more sodium ion diffusion channels than batteries with single tubes and four-leaf clover-shaped ceramic tubes. At the same time, when using a multi-tube combination, the diffusion distance of sodium ions is further shortened, which is conducive to improving the power density of sodium-chloride batteries.

[0059] Taking the nine-tube layout as an example, assuming that the inner diameter of each beta-Al2O3 ceramic tube is 16.8mm and the length is 250mm (excluding the length of the hemispherical part), the volume of the positive electrode material that the nine ceramic tubes can accommodate is: V 16.8 =9×(2 / 3πr 3 +πr 2 h)=9×[2 / 3π×(1.68 / 2) 3 +π(1.68 / 2) 2 × 25]=509(cm 3 ), the total surface area of the nine ceramic tubes is: S 16.8 =9×(2πr 2 +2πrh)=9×[2π×(1.68 / 2) 2 +2π×(1.68 / 2)×25]=1227(cm 2 The beta-Al2O3 ceramic tube weighs 655g; 509cm 3 The space can accommodate a composite positive electrode weighing about 1200g, a battery capacity of 120Ah, and a battery energy of 310Wh. The specific energy of the battery is 167Wh / kg (based on the weight of the ceramic tube and the composite positive electrode), and the specific power of the battery is 250W / L (based on 509cm 3 effective volume).

[0060] Compared with Comparative Example 1 and Comparative Example 2, it can be seen that under the premise of equal volume of positive electrode material, when a combination of 9 small tubes with an inner diameter of 16.8 mm is used, the total surface area S 16.8 1227cm 2 , is a single ceramic tube S with an inner diameter of 50mm 50 Nearly three times (416cm 2 ), which is nearly twice the surface area of a four-leaf clover-shaped ceramic tube of equal volume (644 cm 2 ), the specific power increased from 132W / L to 250W / L, but the specific energy decreased from 181Wh / kg to 167Wh / kg. This shows that the battery structure with a nine-tube combination has a much larger electrochemical reaction area than the battery with a single tube and a four-leaf clover-shaped ceramic tube structure, but the greater the number of ceramic tubes, the higher the proportion of the ceramic tube weight itself, which in turn reduces the energy density of the battery. Therefore, when optimizing the battery structure design and determining the number and size of ceramic tubes, it is necessary to strike a balance between specific energy and specific power to meet application requirements.

[0061] Through the calculations of Examples 1 and 2, it can be seen that the battery structure using a multi-tube combination has a larger electrochemical reaction interface than the battery with a single tube and a four-leaf clover-shaped ceramic tube structure of equal volume, and as the tube diameter decreases and the number increases, the electrochemical reaction interface also increases. At the same time, when a multi-tube combination is adopted, the diffusion distance of sodium ions is further shortened, which is conducive to improving the power density of the sodium-chloride battery. In other words, the use of a small-diameter, multi-tube layout structure effectively increases the electrochemical reaction interface and improves the power density of the battery. Undoubtedly, when a larger number of small-diameter ceramic tubes are used for combination, the electrochemical reaction interface of the prepared sodium-chloride battery will be further increased.

[0062] Furthermore, the above-mentioned combination of multiple electrolyte ceramic tubes is used to prepare corresponding batteries respectively, and the raw materials used also include: insulating ceramic matrix alpha-Al2O3 ceramic, composite positive electrode (containing Ni, NaCl, Fe, FeS, C, NaF and NaAlCl4), conductive shell (stainless steel shell), bottom end cover (stainless steel), current collecting electrode (nickel-plated copper conductor), conductive cover (stainless steel), high borosilicate glass insulating sealing medium, first metal ring, second metal ring, stainless steel pole ear, carbon fiber filling material, etc. The preparation process includes: (1) lowering the mouth of multiple electrolyte ceramic tubes and placing them in the card slot of the insulating ceramic matrix with the corresponding number of through parts; (2) placing the first metal ring on the upper part of the insulating ceramic matrix and the second metal ring on the lower part of the insulating ceramic matrix; (3) filling the gap between the insulating ceramic matrix and the electrolyte ceramic tube, the first metal ring, and the second metal ring with high borosilicate glass insulating sealing medium; (4) heating treatment (if using sealant, curing treatment is required) to achieve the packaging between the insulating sealing medium and the various components; (5) using laser welding technology The shell of the conductive shell is welded to the first metal ring; (6) the composite positive electrode is injected into the ceramic tube; (7) the current collecting electrode is welded to the conductive cover, passed through the through-hole, and inserted into the composite positive electrode; (8) the conductive cover is connected to the second metal ring by laser welding technology; (9) carbon fiber filling material (i.e., conductive material) is injected into the cavity formed between the conductor shell and the electrolyte ceramic tube; (10) under vacuum conditions, the bottom end cover is welded to the shell of the conductive shell; (11) the stainless steel pole ear is welded to the conductive cover.

[0063] Table 1 shows the structure and performance parameters of the sodium-chloride battery with a high reaction interface prepared by the present invention:

[0064]

[0065] The power density is calculated based on 40mA / cm 2 The current density is calculated based on the total volume of the ceramic tube. The energy density calculation only considers the weight of the composite cathode material and the electrolyte ceramic tube, with the wall thickness of the ceramic tube uniformly calculated as 1.5mm. Overall, the 4-tube and 5-tube batteries offer the best performance, combining high specific power and high specific energy.

[0066] Without departing from the purpose of the basic characteristics of the present invention, the present invention can be embodied in various forms. Therefore, the embodiments of the present invention are used for illustration rather than limitation. Since the scope of the present invention is limited by the claims rather than the description, all changes that fall within the scope defined by the claims or the equivalent range of the scope defined by them should be understood to be included in the present invention.

Claims

1. A sodium-chloride battery with a highly reactive interface, characterized in that: It consists of the following parts: A conductive shell having an open end, wherein the conductive shell has a plurality of electrolyte ceramic tubes distributed in an array; A conductive cover portion, used for closing the open end connected to the conductive shell; An insulating ceramic substrate is provided between the conductive shell and the conductive cover and fixed to the conductive cover for carrying a plurality of electrolyte ceramic tubes. An upper through hole and a lower through hole of different diameters are formed in the middle of the insulating ceramic substrate. The diameter of the lower through hole is less than the outer diameter of the electrolyte ceramic tube and less than the diameter of the upper through hole, forming a slot for carrying the open end of the electrolyte ceramic tube. An insulating sealing medium is provided between the upper through hole and the electrolyte ceramic tube in the insulating ceramic substrate to form two isolated spaces: one between the inside of the electrolyte ceramic tube and the conductive cover, and the other between the outside of the electrolyte ceramic tube and the conductive shell. The space between each electrolyte ceramic tube and the conductive cover includes a positive electrode material and a current collecting electrode, and the current collecting electrode passes through the through hole of the insulating ceramic substrate and is connected to the conductive cover to be led out; Conductive material is filled between the conductive shell and the outside of each electrolyte ceramic tube; The positive electrode material is a mixture containing at least one of Ni and Fe, NaCl and NaAlCl4.

2. The sodium-chloride battery with a highly reactive interface according to claim 1, characterized in that The electrolyte ceramic tube is made of beta-Al2O3 and a sodium ion conductor; the insulating ceramic matrix is alpha-Al2O3 ceramic; and the conductive material is selected from at least one of carbon and metal.

3. The sodium-chloride battery with a highly reactive interface according to claim 1, characterized in that The number of the electrolyte ceramic tubes is 3 to 9.

4. The sodium-chloride battery having a highly reactive interface according to any one of claims 1 to 3, characterized in that The conductive cover is provided with a tab; the conductive shell comprises a shell and a bottom end cover.

5. The sodium-chloride battery with a highly reactive interface according to claim 1, characterized in that The insulating sealing medium is sealing glass, ceramic sealant or sealant.

6. The sodium-chloride battery having a highly reactive interface according to any one of claims 1 to 3, characterized in that: A first metal ring is provided between the insulating ceramic base and the conductive shell, and / or a second metal ring is provided between the insulating ceramic base and the conductive cover.

7. The sodium-chloride battery with a highly reactive interface according to claim 6, characterized in that The first metal ring and the second metal ring are made of Kovar, stainless steel, Ni or aluminum alloy.

8. The sodium-chloride battery with a highly reactive interface according to claim 6, characterized in that An insulating sealing medium is provided between the insulating ceramic substrate and the metal ring; the insulating sealing medium is sealing glass, ceramic sealant or sealing glue.

9. The sodium-chloride battery with a highly reactive interface according to claim 1, characterized in that The positive electrode material also contains at least one of C, Cu, Co, Zn, FeS, NaF, NaBr, and NaI.

10. The sodium-chloride battery having a highly reactive interface according to any one of claims 1 to 3, characterized in that The current collecting electrode is a copper conductor with nickel plating on the surface, a pure nickel conductor, an Fe conductor, or a carbon material conductor; the material of the cover and the conductive shell is stainless steel or aluminum alloy; the shape of the conductive shell is a round tube or a square tube.

11. The sodium-chloride battery having a highly reactive interface according to any one of claims 1 to 3, characterized in that The size of the electrolyte ceramic tube is 15-60 mm, and the wall thickness is 0.5-3 mm.

12. The sodium-chloride battery with a highly reactive interface according to claim 11, characterized in that The size of the electrolyte ceramic tube is 20-40 mm, and the wall thickness is 1-1.5 mm.

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