WO2021258289A1

WO2021258289A1 - Solid-state storage device for gas and method for manufacturing same

Info

Publication number: WO2021258289A1
Application number: PCT/CN2020/097728
Authority: WO
Inventors: 李长鹏; 吴琪; 周忠娇; 陈国锋
Original assignee: 西门子股份公司; 西门子（中国）有限公司
Priority date: 2020-06-23
Filing date: 2020-06-23
Publication date: 2021-12-30
Also published as: CN115335320A

Abstract

A solid-state storage device for hydrogen and a method for manufacturing same. The solid-state storage device comprises a housing, and the housing comprises a receiving space, in which a plurality of adsorption elements are disposed (200). The method for manufacturing a solid-state storage device for hydrogen comprises the following steps: pouring activated carbon powder into a molding cylinder (130) of a binder injection molding device, and performing glue printing from bottom to top according to a model of the adsorption elements so as to form an adsorption layer (201); mixing spherical graphite and a binder and feeding same into a liquid binder supply device (110) of the binder injection molding device (100), and spraying on the adsorption layer (201) from bottom to top according to the model of the adsorption elements so as to form a thermally conductive layer (202); iteratively performing the steps above until the plurality of adsorption elements (200) are formed in the housing. The adsorption elements (200) each comprise, arranged at intervals, a plurality of the adsorption layers (201) and the thermally conductive layers (202). The described device increases the volume and mass density of the solid-state storage device for hydrogen, improves the storage efficiency of hydrogen, and at the same time, ensures relatively high hydrogen adsorption and release rates.

Description

Gas solid-state storage device and manufacturing method thereof

Technical field

The invention relates to the field of additive manufacturing, in particular to a gas solid-state storage device and a manufacturing method thereof.

Background technique

Today, the market for rechargeable cars is growing rapidly, but it still faces many challenges, including using a battery to achieve a relatively short driving distance under a fully charged state, a slow charging rate, and low battery efficiency and difficulty in recycling. The above restrictions have become a major obstacle to widespread recognition of electric vehicles replacing traditional fuel vehicles.

Considering this problem, more and more attention is paid to fuel cell vehicles based on hydrogen fuel in the automotive field. Hydrogen is an ideal clean energy. It can be produced by renewable energy and only produces water as a discharge. Moreover, as a new energy source, hydrogen has a high energy density. Its energy density is about three times that of gasoline per unit mass, and it is also much higher than that of batteries. Using hydrogen as a fuel source, fuel vehicles have similar driving distances and charging rates as traditional vehicles.

However, in addition to the high weight energy density, the extremely low capacity storage density of hydrogen has also become an obstacle to its use as a new energy fuel for automobiles.

Especially for fuel cell vehicles, hydrogen can be stored in at least three ways: compressed gas storage, cryogenic liquid storage, and solid-state storage. The compressed gas storage method requires a large storage tank to withstand high pressure gas below 700 bar, and it also requires high compression energy and high strength storage tanks. Cryogenic liquid storage requires high economic investment, and there are always various energy losses during the manufacturing process, such as evaporation during refilling. Therefore, the adsorption and/or absorption of hydrogen on materials or alloys becomes an economical solution. For example, super activated carbon ( ^{AX-21 with a high surface area greater than 3000 m 2} /g) is used as an adsorption material.

However, AX-21 powder has a very high density (0.3 g/cm ³ ), which results in a low volume adsorption capacity of ^{less than 20 g H 2 /l.} In addition, the hydrogen adsorption and absorption power are also limited due to the relatively low thermal conductivity of AX-21 powder. In addition, AX-21 powder can block the fuel system or enter the fuel chamber of the engine, which is a situation that needs to be avoided.

In order to solve the above-mentioned problems, block materials such as columnar or rectangular parallelepiped are prepared by mixing with the adhesive and then performing mechanical compression and heat treatment to achieve a concentration of ^{0.6-0.9 g/cm 3.} However, considering the hydrogen adsorption and absorption rate, the bulk material has a size limit. It takes a lot of time to assemble the AX-21 block into the storage tank, and it can also be damaged due to the relative movement and friction between the blocks during the operation of the vehicle. The relatively low thermal conductivity will also cause the block to crack due to uneven thermal expansion during the process of hydrogen adsorption and absorption.

Summary of the invention

The first aspect of the present invention provides a gas solid-state storage device manufacturing method, wherein the solid-state storage device includes a housing, the housing includes a housing space, the housing space is provided with a plurality of adsorption elements, the gas The solid-state storage device manufacturing method includes the following steps: pour activated carbon powder into the molding cylinder of the binder injection molding device, and perform glue printing from bottom to top according to the model of the adsorption element to form an adsorption layer; The agent is mixed into the liquid adhesive supply device of the adhesive injection molding device, and a thermally conductive layer is sprayed on the adsorption layer from bottom to top according to the model of the adsorption element; the above steps are performed iteratively until the shell A plurality of adsorption elements is formed in the, wherein the adsorption unit includes a plurality of the adsorption layer and the heat conduction layer arranged at intervals.

Further, a plurality of cavities are provided in the adsorption layer and/or the thermally conductive layer, wherein the method for manufacturing the gas solid-state storage device further includes the following step: in the molding cylinder of the adhesive injection molding device Spread activated carbon powder, and fill the adsorption element with activated carbon powder in accordance with the model of the adsorption element while forming the adsorption layer and the heat-conducting layer, wherein the model of the adsorption element is in the adsorption layer and/or A plurality of holes or grooves are provided in the heat conducting layer, and the plurality of holes or grooves are connected to form a gas flow pipe.

Further, the method for manufacturing the gas solid-state storage device further includes the following steps: performing a sintering process on the plurality of adsorption elements that are integrally formed to form the gas solid-state storage device, and at the same time adopting a method of chemical dissolution or thermal decomposition Removing the binder in the adsorption element; removing the activated carbon powder filled in the adsorption layer and/or the heat conducting layer to form a gas flow pipe in the gas solid storage device.

Further, the method for manufacturing the gas solid-state storage device further includes the following step: performing a hot isostatic pressing process on the plurality of adsorption elements that are integrally formed.

Further, after the hot isostatic pressing process, the method further includes the following step: performing a vacuum heat treatment process on the plurality of adsorption elements that are integrally formed.

Further, the hot isostatic pressing process is performed in a hot isostatic pressing process furnace, wherein the gas input into the hot isostatic pressing process furnace includes nitrogen or argon, and the process temperature ranges from 100 to 500 ℃, the treatment time is 5-20 hours.

Further, it also includes the following step: adjusting the viscosity of the thermally conductive layer by controlling the ratio of the adhesive, its solvent, and spherical graphite.

Further, it also includes the following step: assembling the plurality of adsorption units in the housing.

The second aspect of the present invention provides a gas solid-state storage device, which is characterized in that the gas solid-state storage device is manufactured according to the gas solid-state storage device manufacturing method according to the first aspect of the present invention.

Further, the gas is hydrogen.

The present invention provides an economical gas solid-state storage device manufacturing method, which is manufactured by an adhesive injection molding device. The gas solid-state storage device manufactured by the invention has high quality, simple and convenient procedures, and avoids damage caused by stacking traditional solid-state storage block devices. In addition, the hydrogen solid-state storage device manufactured by the present invention has an adsorption layer and a heat-conducting layer arranged at intervals, which ensures a good adsorption capacity and power of hydrogen, and has good thermal conductivity, which can avoid the absorption of hydrogen during the heat treatment process due to the traditional manufacturing method. Possible damage caused by absorbing energy. In addition, the present invention can realize the manufacture of as many adsorption elements as possible through 3D printing in the limited hydrogen solid storage device space, and can ensure the rapid adsorption and release rate of hydrogen. In addition, the present invention compresses the adsorption element through the hot isostatic pressing process, which can obtain higher mass and volume density, thereby obtaining a higher volumetric hydrogen storage density. The invention also guarantees a higher hydrogen adsorption and release speed.

Description of the drawings

Figure 1 is a schematic diagram of the structure of an adhesive injection molding device provided by the present invention;

2 is a schematic structural diagram of an adsorption element of a hydrogen solid-state storage device according to a specific embodiment of the present invention;

Fig. 3 is a schematic structural diagram of a hydrogen gas flow pipe provided with an adsorption element of a hydrogen solid-state storage device according to a specific embodiment of the present invention.

detailed description

The specific embodiments of the present invention will be described below with reference to the accompanying drawings.

The invention uses the additive manufacturing process of binder jetting technology to provide a solid gas storage mechanism based on the 3D model of the adsorption element, so as to obtain a high-volume storage capacity and high-efficiency one-piece hydrogen adsorption And absorbing elements. Among them, the present invention mainly uses AX21 activated carbon powder. Among them, the preferred embodiment of the present invention utilizes a liquid binding agent (liquid binding agent) to be deposited layer by layer on the laying powder material, and then multiple post-processing steps are performed. Preferably, the print head of the adhesive jet forming device provided by the present invention integrates thousands of holes, so that multiple complex structures can be printed quickly.

The gas is preferably hydrogen, and the present invention will be described below by taking hydrogen as an example

The present invention utilizes a binder injection molding device. Fig. 1 is a schematic structural diagram of an adhesive injection molding device provided by the present invention. Adhesive injection molding technology utilizes spreading powder layer by layer. Subsequently, the inkjet print head sprays the adhesive into the 3D printing material (usually powder), so that the powder not only adheres to itself, but also penetrates and combines with the previous powder material layer, and layer by layer to form a prototype, and then pass High-temperature sintering removes the binder and promotes the fusion and connection of powder particles, so as to obtain 3D printed parts with ideal density and strength. Binder injection molding technology is suitable for printing metal and ceramic materials. As shown in FIG. 1, the adhesive injection molding device 100 includes a liquid adhesive supply device 110, a powder feeding cylinder 120, a molding cylinder 130, and a spray head 140. A first piston 122 is provided below the space where the powder feeding cylinder 120 contains the printing powder. With the vertical movement of the first piston 122 from bottom to top, the printing powder can be lifted up as a whole, and then the upper roller 124 passes through The left and right planes roll to feed the printing powder into the forming cylinder 130. A second piston 132 is also provided under the powder bed 134 of the forming cylinder 130. During the 3D printing process, the second piston 132 moves from top to bottom to form a printing space in the forming cylinder 130. The liquid adhesive supply device 110 is used to supply liquid adhesive to the spray head 140, and the spray head 140 sprays the adhesive into the printing powder in the powder bed 134, so that the powder penetrates together through the adhesive bonding and flows from the bottom. The upper layers are superimposed to form a 3D prototype. Among them, the prototype formed by the binder injection molding technology has not been sintered, which is equivalent to the embryo body formed according to the 3D printing model.

It should be noted that the advantage of the adhesive injection molding technology is that it can print multiple prototypes from the bottom up, which is more efficient and more controllable.

Wherein, the solid-state storage device for storing hydrogen includes a housing, and the housing includes a accommodating space. Wherein, the solid-state storage device is, for example, a rectangular parallelepiped housing with a certain height, and as many adsorption elements as possible are arranged according to the rectangular housing. The prior art uses activated activated carbon powder to store gases such as hydrogen and methane, but since activated carbon is in powder form, the activated carbon powder will move once the gas enters. Therefore, in the present invention, the activated carbon serving as a hydrogen carrier is compressed into small pieces of adsorption elements, and the activated carbon adsorption elements in the shell can adsorb hydrogen, so more gas can be stored. The activated carbon in the prior art has small pores, and hydrogen gas enters into a liquid. If the small pores are blocked, there is a problem of heat dissipation.

The first aspect of the present invention provides a method for manufacturing a hydrogen solid-state storage device, which uses a 3D printing method to print a plurality of adsorption elements arranged in a solid-state storage device housing from bottom to top, and at the same time, a hydrogen flow pipe is formed in the adsorption element. And a layer of thermally conductive material.

Specifically, the method for manufacturing a hydrogen solid-state storage device includes the following steps:

First, perform step S1, pour activated carbon powder into the molding cylinder 130 of the binder injection molding device 100, and perform glue printing from bottom to top according to the model of the adsorption element to form the adsorption layer, for example, as shown in FIG. 2 The adsorption layer 201 in the adsorption element 200. Among them, the adhesive for spraying can be selected from PVDF, PVA or PTFE mixed in a solvent. PTFE and PVA are exemplarily dissolved in water, and PVDF is dissolved in a xylene solvent.

Then step S12 is performed to mix the spherical graphite and the binder into the liquid binder supply device 110 of the binder injection molding device 100, and spray the adsorption layer 201 from bottom to top according to the model of the adsorption element A thermally conductive layer 202 is formed.

Specifically, considering the thermal conductivity of AX21 activated carbon powder, fine-grained granular graphite particles are smaller in size than AX21 activated carbon powder, so they will be directly added to the binder through the nozzle 140 of the liquid binder supply device 110 Spray on the upper surface of the previous adsorption layer 201. As shown in FIG. 2, the thickness of the adsorption layer 201 is 50-100 μm. The adhesive sprayed on the surface will penetrate and adhere to the AX21 activated carbon powder, so the adhesive will partially penetrate the previous adsorption layer 201. However, at the same time, the spherical graphite will stay on the adsorption layer 201 and form a thermally conductive layer 202 with high thermal conductivity. The number of spheroidal graphite is tuned to obtain the desired high thermal conductivity thermally conductive layer 202, but it does not affect the hydrogen absorption capacity and power. Wherein, the spherical graphite acts as the thermally conductive particles B in the thermally conductive layer 202.

The above steps S1 and S2 are performed iteratively until a plurality of adsorption elements 200 are formed in the housing, wherein the adsorption unit 200 includes a plurality of the adsorption layer and the heat conduction layer arranged at intervals. The adsorption unit 200 shown in FIG. 2 first forms an adsorption layer 201, then forms a thermally conductive layer 202 on the adsorption layer 201, then forms an adsorption layer 203 and a thermally conductive layer 204, and finally forms a layer of adsorption层205.

Wherein, the thermal conductive layer 204 is formed by spraying spherical graphite mixed into the adhesive, and spherical graphite is added to serve as thermal conductive particles B. If the adsorption unit 200 only includes an adsorption layer of activated carbon, its thermal conductivity is not good. Once hydrogen is absorbed by the adsorption unit 200 with only an adsorption layer of activated carbon, heat will be generated. An increase in temperature will affect the absorption effect of hydrogen, and a low temperature is more conducive to the absorption and adsorption of hydrogen by the adsorption unit 200. In addition, the adsorption unit 200 with only the activated carbon adsorption layer is prone to cracks, that is, cracks caused by thermal expansion and contraction. If the adsorption unit 200 adopts the adsorption layer and the heat conduction layer that are arranged at intervals, since the thermally conductive particles of the heat conduction layer 204 are mixed in the elastic layer, the cracking of the activated carbon adsorption layer caused by thermal expansion and contraction will be avoided, and the adsorption unit 200 can be reduced. The overall temperature is conducive to the absorption of hydrogen.

Preferably, the present invention can also obtain the optimized viscosity of the thermally conductive layer by controlling the ratio of the adhesive, its solvent, and spherical graphite.

Preferably, a plurality of cavities are provided in the adsorption layer and/or the thermally conductive layer, wherein the method for manufacturing the hydrogen solid-state storage device further includes the following steps: in the molding cylinder of the adhesive injection molding device 100 Activated carbon powder is spread in 130, and the adsorption layer and the heat conduction layer are formed while filling the adsorption element 200 with activated carbon powder according to the model of the adsorption element 200, wherein the model of the adsorption element is in the adsorption A plurality of holes or grooves A are provided in the layer and/or the thermally conductive layer, and the plurality of holes or grooves A are connected to form a hydrogen flow pipeline.

Specifically, in order to improve the absorption rate and the absorption rate of the adsorption element, the hydrogen diffusion length can be reduced with a designed internal hydrogen pipeline matrix. As shown in Fig. 3, without spraying glue/adhesive, AX21 activated carbon powder is filled with activated carbon powder in the adsorption unit 200 to form a plurality of unstable activated carbon powder regions in the plurality of holes or grooves A . Among them, since the other areas of the adsorption unit 200 are formed by spray glue and have a certain strength, multiple activated carbon powder areas will form cavities/holes after the activated carbon powder is removed after the printing process is completed, thereby acting as Hydrogen flow pipeline. The hydrogen gas flows rapidly in the hydrogen flow pipe formed by the above-mentioned multiple activated carbon powder regions to be adsorbed and absorbed by the adsorption unit 200, so as to achieve the purpose of hydrogen storage.

Specifically, a solid-state storage device for hydrogen includes two key indicators: hydrogen storage density and hydrogenation rate, and hydrogen storage density includes volume density and mass density. Among them, the mass density of the activated carbon of the adsorption unit is very high, and the bulk density is very small if it is not compressed. Therefore, it is necessary to balance the mass density and bulk density of the adsorption unit. Therefore, in the present invention, as many adsorption units as possible are printed integrally in the housing of a solid-state storage device containing hydrogen with limited space. Under the premise of ensuring the hydrogen storage density of the activated carbon adsorption layer of the adsorption unit, the adsorption layer and the /Or a hydrogen flow pipe is formed in the heat-conducting layer to ensure that the hydrogenation rate does not decrease.

In contrast to the prior art, hot pressing is performed after the material powder is added with the binder, that is, the adsorption unit is pressed by a high-pressure machine with a mold. Since this can only be done one adsorption unit at a time, only the completed adsorption units can be stacked together. Therefore, it is easy to collide during transportation, and it is difficult to assemble and assemble. In practice, the solid-state storage device of hydrogen formed by this manufacturing method will have a service life problem.

Traditional hydrogen solid-state storage devices use a mold hot pressing process to prepare bulk materials to increase bulk density. In the present invention, the solid-state storage device of hydrogen produced by the adhesive injection molding device cannot reach the desired density. Therefore, the following steps are included after step S2:

Step S3: Perform a sintering process on the multiple adsorption elements that are integrally formed to form the hydrogen solid-state storage device, and at the same time, use a method of chemical dissolution or thermal decomposition to remove the binder in the adsorption element.

Step S4, removing the activated carbon powder filled in the adsorption layer and/or the thermally conductive layer to form a hydrogen flow pipe in the hydrogen solid storage device.

Then, step S5 is performed to perform a hot isostatic pressing process on the multiple adsorption elements that are integrally formed. After the adhesive in the adsorption element is removed, the adsorption unit has good mechanical stability, and it will be moved to a hot isostatic pressing (HIP, Hot Isostatic Pressing) furnace. The hot isostatic pressing process is performed in a hot isostatic pressing process furnace, wherein the gas input into the hot isostatic pressing process furnace includes nitrogen or argon, and the process temperature ranges from 100 to 500°C. The time is 5-20 hours. The input gas in the hot isostatic pressing process furnace includes nitrogen or argon, the pressure in the furnace is less than 400 Bar, and the process temperature is 100 to 500°C. The above-mentioned specific process parameters vary according to the selected adhesive. Taking the PVA adhesive as an example, the solid-state storage device of hydrogen will be treated in a hot isostatic pressing process furnace at a temperature range of 150-200°C for 10 to 20 hours to remove any possible residue inside. Of water or adhesive.

Wherein, the hot isostatic pressing process uses high-temperature gas to compress the multiple adsorption units that have been manufactured, and the use of gas compression is to directly enter the pores of the adsorption unit through the gas, so the inside and outside of the adsorption unit are filled with gas, which will compress the adsorption unit. . Compression performed by the hot isostatic pressing process will not damage the structure of the adsorption unit, especially the cavity in the adsorption unit. Under this premise, the structure will be solidified to make the adsorption unit more compact and compact. Therefore, the volume density of the adsorption unit of the hydrogen solid-state storage device manufactured by the present invention is further improved.

Then, step S6 is performed, and after the hot isostatic pressing process, the following step is further included: performing a vacuum heat treatment process on the plurality of adsorption elements that are integrally formed.

The second aspect of the present invention provides a hydrogen solid-state storage device, which is characterized in that the hydrogen solid-state storage device is manufactured according to the method for manufacturing a hydrogen solid-state storage device according to the first aspect of the present invention.

The present invention provides an economical hydrogen solid-state storage device manufacturing method, which is manufactured by a binder injection molding device. The hydrogen solid-state storage device manufactured by the present invention has high quality, simple and convenient procedures, and avoids damage caused by stacking of traditional solid-state storage block devices. In addition, the hydrogen solid-state storage device manufactured by the present invention has an adsorption layer and a heat-conducting layer arranged at intervals, which ensures a good adsorption capacity and power of hydrogen, and has good thermal conductivity, which can avoid the absorption of hydrogen during the heat treatment process due to the traditional manufacturing method. Possible damage caused by absorbing energy. In addition, the present invention can realize the manufacture of as many adsorption elements as possible through 3D printing in the limited hydrogen solid storage device space, can ensure the rapid adsorption and release rate of hydrogen, and reduce the time required for hydrogenation. In addition, the present invention compresses the adsorption element through the hot isostatic pressing process, which can obtain higher mass and volume density, thereby obtaining a higher volumetric hydrogen storage density. The invention also guarantees a higher hydrogen adsorption and release speed.

Although the content of the present invention has been described in detail through the above preferred embodiments, it should be recognized that the above description should not be considered as limiting the present invention. After those skilled in the art have read the above content, various modifications and substitutions to the present invention will be obvious. Therefore, the protection scope of the present invention should be defined by the appended claims. In addition, any reference signs in the claims should not be regarded as limiting the involved claims; the word "comprising" does not exclude other claims or devices or steps not listed in the specification; "first", "section Words such as "two" are only used to indicate names, and do not indicate any specific order.

Claims

A method for manufacturing a gas solid-state storage device, wherein the solid-state storage device includes a housing, the housing includes an accommodating space, and a plurality of adsorption elements are arranged in the accommodating space, and the manufacturing method of the gas solid-state storage device includes the following step:

Pour activated carbon powder into the molding cylinder of the binder injection molding device, and perform glue printing from bottom to top according to the model of the adsorption element to form the adsorption layer;

Mixing spherical graphite and adhesive into the liquid adhesive supply device of the adhesive injection molding device, and spraying on the adsorption layer from bottom to top according to the model of the adsorption element to form a thermally conductive layer;

The above steps are performed iteratively until a plurality of adsorption elements are formed in the housing, wherein the adsorption unit includes a plurality of the adsorption layer and the heat conduction layer arranged at intervals.
The method for manufacturing a gas solid-state storage device according to claim 1, wherein a plurality of cavities are provided in the adsorption layer and/or the thermally conductive layer, wherein the method for manufacturing the gas solid-state storage device It also includes the following steps:

Pour activated carbon powder in the molding cylinder of the binder injection molding device, and fill the activated carbon powder in the adsorption element according to the model of the adsorption element while forming the adsorption layer and the heat conduction layer,

Wherein, the model of the adsorption element is provided with a plurality of holes or grooves in the adsorption layer and/or the heat conducting layer, and the plurality of holes or grooves are connected to form a gas flow pipeline.
The method for manufacturing a gas solid-state storage device according to claim 1, wherein the method for manufacturing a gas solid-state storage device further comprises the following steps:

Performing a sintering process on the plurality of integrated adsorption elements to form a solid-state storage device for the gas, and at the same time removing the binder in the adsorption elements by a method of chemical dissolution or thermal decomposition;

The activated carbon powder filled in the adsorption layer and/or the heat conduction layer is removed to form a gas flow pipe in the gas solid storage device.
The method for manufacturing a gas solid-state storage device according to claim 1, wherein the method for manufacturing a gas solid-state storage device further comprises the following step: performing hot isostatic pressing on the plurality of adsorption elements that are integrally formed Process.
The method for manufacturing a gas solid-state storage device according to claim 4, characterized in that, after the hot isostatic pressing process, the method further comprises the following step: performing a vacuum heat treatment process on the plurality of adsorption elements that are integrally formed.
The method of manufacturing a gas solid-state storage device according to claim 4, wherein the hot isostatic pressing process is performed in a hot isostatic pressing process furnace, wherein the gas is input into the hot isostatic pressing process furnace Including nitrogen or argon, the process temperature ranges from 100 to 500°C, and the processing time is from 5 to 20 hours.
The method for manufacturing a gas solid-state storage device according to claim 1, characterized in that it further comprises the following steps:

The viscosity of the thermal conductive layer is adjusted by controlling the ratio of the adhesive, its solvent, and spherical graphite.
The method for manufacturing a gas solid-state storage device according to claim 1, further comprising the step of assembling the plurality of adsorption units in the housing.
The method for manufacturing a gas solid-state storage device according to claim 1, wherein the gas is hydrogen.
The gas solid-state storage device is characterized in that the gas solid-state storage device is manufactured according to the method for manufacturing a gas solid-state storage device according to any one of claims 1 to 9.