Inner container keeping method in IV type hydrogen storage bottle manufacturing process

Abstract

The invention provides a method for keeping an inner container in the manufacturing process of an IV-type hydrogen storage bottle. The technical problem that the inner container is prone to collapse in the manufacturing process of an existing IV-type hydrogen storage bottle is solved. Before the adsorption material is wound on the liner of the IV-type hydrogen storage bottle, the support equipment in the contracted state extends into the liner and is stretched and unfolded to be tightly attached to the inner surface of the liner for supporting; and the supporting equipment is equipment with a negative Poisson's ratio structure, is in a rod shape when being contracted, expands when being deformed and stretched, and is matched with the liner structure of the IV type hydrogen storage bottle.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogen storage bottle preparation technology, and specifically relates to a method for maintaining an inner liner during the manufacturing process of a type IV hydrogen storage bottle. The method can prevent the inner liner from collapsing during the manufacturing process. Background Art

[0002] In order to achieve carbon neutrality and a sustainable energy economy for human development society, low-cost and reliable energy storage technology is essential. The world today is facing increasingly serious oil crises and environmental pollution problems, and there is an urgent need to develop new clean and economical energy sources. In order to reduce carbon emissions, countries around the world have successively announced a timetable for banning the sale of fuel vehicles. Replacing some fuel vehicles are hydrogen fuel cell vehicles (FCVs) and pure electric vehicles, which are known for their cleanliness and pollution-free. Hydrogen energy is considered to be the ultimate energy source for automobiles with its zero-emission characteristics. The history of human use of hydrogen energy can be traced back to the 1830s, when Willian Grove invented the world's first fuel cell, opening the door to human use of hydrogen energy. Today, major automobile manufacturers around the world have successively launched hydrogen fuel cell vehicles. The more famous ones are Toyota's Miria, Honda's Clarity, Hyundai's IX35 and SAIC's Roewe E950.

[0003] Hydrogen storage is a bridge between hydrogen production and use, and plays an irreplaceable role in the development of hydrogen energy. So far, almost all hydrogen storage equipment and hydrogen transmission equipment are subject to hydrogen pressure, and are pressure-bearing equipment among special equipment, among which gas cylinders are a more common type. With the rapid development and industrialization of hydrogen fuel cells and electric vehicles, Type IV hydrogen storage bottles are becoming a global research hotspot due to their light weight and fatigue resistance. Type IV hydrogen storage bottles have been mass-produced in Japan, South Korea, the United States, Norway and other countries, and other countries also have plans to increase their research efforts on Type IV hydrogen storage bottles.

[0004] At present, on-board high-pressure gaseous hydrogen storage bottles mainly include aluminum liner fiber-wound bottles (Type III) and plastic liner fiber-wound bottles (Type IV). Type IV hydrogen storage bottles have many advantages, such as low cost, high hydrogen storage density, corrosion resistance, fatigue resistance, and no metal fragments after bursting. Specifically, for Type IV bottles, the usual manufacturing method is to wrap composite materials around the liner to strengthen it, but when the composite materials are wrapped around the outside, the plastic liner is prone to collapse and deformation. The traditional method is to pressurize the liner to maintain the shape of the liner, but because the liner of the Type IV hydrogen storage bottle is made of polymer material, it has higher permeability than the metal liner of the Type III hydrogen storage bottle (high permeability causes part of the gas to enter between the liner and the winding layer). Therefore, during the rapid decompression process, due to the rapid discharge of gas, a pressure difference will be formed inside and outside the liner, and external pressure will be applied to the liner, causing the liner to collapse. Therefore, the response strategy for the special failure mode of collapse during the manufacturing process of the liner of the Type IV hydrogen storage bottle is of great significance to the promotion and application of IV hydrogen storage bottles.

[0005] Based on this, the research team of the present invention believes that it is necessary to provide a better method for dealing with the collapse of the inner liner of Type IV hydrogen storage bottles. Summary of the invention

[0006] The purpose of the present invention is to solve the technical problem that the inner liner of the existing IV type hydrogen storage bottle is prone to collapse during the manufacturing process, and to provide a method for maintaining the inner liner during the manufacturing process of the IV type hydrogen storage bottle.

[0007] To achieve the above purpose, the technical solution provided by the present invention is:

[0008] A method for retaining an inner liner during the manufacturing process of a type IV hydrogen storage bottle, the special features of which are:

[0009] Before the inner liner of the IV type hydrogen storage bottle is wrapped with the adsorbent material, the support device in a contracted state is extended into the inner liner, stretched and expanded to closely adhere to the inner surface of the inner liner for support;

[0010] The supporting device is a device with a negative Poisson's ratio structure. When it is contracted, it is rod-shaped. When it is deformed and stretched, its volume expands to an open state, which is compatible with the inner liner structure of a Type IV hydrogen storage bottle.

[0011] In addition, the present invention also provides a method for manufacturing a type IV hydrogen storage bottle, the special features of which are:

[0012] Before the inner liner is wound with the adsorbent material, the support device in a contracted state is extended into the inner liner, stretched and unfolded to be close to the inner surface of the inner liner for support; after the adsorbent material is wound, the support device is contracted and taken out; the steps are the same as those of the existing preparation process;

[0013] The supporting device is a device with a negative Poisson's ratio structure. When it is contracted, it is rod-shaped. When it is deformed and stretched, its volume expands to an open state, which is compatible with the inner liner structure of a Type IV hydrogen storage bottle.

[0014] Further, the support device includes a gripping rod, a pushing assembly, a control assembly, a supporting film and a frame connecting assembly;

[0015] The frame connection assembly is coaxially fixedly arranged on the gripping rod;

[0016] The supporting film is bonded to the outer peripheral surface of the frame connection assembly;

[0017] The middle part of the pushing assembly is slidably connected to the holding rod, and the end part is slidably connected to the frame connecting assembly;

[0018] The control component controls the pushing component to slide up and down along the holding rod, driving the frame connection component to shrink and expand, and the supporting film shrinks and expands along with the frame connection component.

[0019] Further, the frame connection assembly includes N body support members, wherein N is an even number not less than 8;

[0020] Each body support is in the shape of an isosceles triangle, and includes a waist bar 1, a waist bar 2 and a bottom bar 1, the ends of which are hinged to each other; all body support members are fixedly arranged on the gripping bar in sequence through the same connecting member along the circumferential direction, and are arranged symmetrically relative to the gripping bar in groups of two; the bottom bars 1 of all body support members are arranged parallel to each other;

[0021] The pushing assembly includes a push rod and a motor;

[0022] The middle parts of the push rods of the two push assemblies are vertically arranged on the gripping rod, respectively located above and below the connecting member, and the two ends of the push rod located above are respectively slidably arranged on one group of symmetrically arranged body support member waist bar 1, and the two ends of the push rod located below are respectively slidably arranged on one group of symmetrically arranged body support member waist bar 2; the length of the push rod is less than the diameter of the inlet of the inner liner of the IV type hydrogen storage bottle;

[0023] The control element is used to control the start and stop of the motor, and the push rod slides up and down along the grip rod under the action of the motor;

[0024] The supporting film is bonded to the outer peripheral surface of the frame connection assembly along all the bottom bars.

[0025] When the support device is in the retracted state, both push rods are away from the connecting piece, the end of the upper push rod is located at the hinge point of waist bar 1 and bottom bar 1, and the end of the lower push rod is located at the hinge point of waist bar 2 and bottom bar 1; when the motor drives the push rod to slide in the direction close to the connecting piece (the two push rods move towards each other), waist bar 1 and waist bar 2 of the body support rely on the support of the push rod and the relative sliding with the push rod to rotate around the connecting piece, and the angle gradually becomes smaller, so that the support device is unfolded. At this time, the push rod is closest to the connecting piece, and the body support pieces are all unfolded, forming a shape that matches the structure of the IV type hydrogen storage bottle liner, and the support film is attached to the inner wall of the liner. After the adsorption material is wound, when the motor drives the push rod to slide in the direction away from the connecting piece (the two push rods move back to back), it rotates around the connecting piece, and the angle gradually becomes larger, so that the support device is retracted. At this time, the push rod is farthest from the connecting piece, and the body support pieces are all retracted and restored to a rod shape.

[0026] Furthermore, in order to make the entire liner support more reliable, N is 12.

[0027] The principle of the present invention is:

[0028] The present invention utilizes a device with a negative Poisson's ratio structure as an inner liner support device, and the support device includes a support film and a frame connection component. The frame connection component has the functions of folding and contracting and stretching and unfolding in terms of mechanical structure design. It can enter the entrance of the inner liner when folded and contracted into a rod shape, and unfold as a whole inside the inner liner of the hydrogen storage bottle when subjected to force deformation and stretching, and stick to the inner wall of the inner liner; the support film is coated on the outer peripheral surface of the frame connection component, and shrinks and unfolds with the frame connection component. After unfolding, the support device contacts the inner liner of the hydrogen storage bottle, plays a bearing role, helps to reduce the pressure at the contact point, and disperses the pressure at the collapse point of the inner liner. Therefore, the use of a support device with a negative Poisson's ratio structure can increase the pressure limit of the collapse of the inner liner, help reduce the collapse of the inner liner during the winding process, and maintain the shape of the inner liner.

[0029] The advantages of the present invention are:

[0030] 1. The present invention provides a method for maintaining the inner liner during the manufacturing process of a type IV hydrogen storage bottle, so as to improve the pressure limit of the inner liner collapse. A type IV hydrogen storage bottle inner liner support device is used, and a film structure is used to assist the inner liner in bearing. Since the entire support device adopts a negative Poisson's ratio structure, when the inner liner reaches the edge of collapse, it contacts the supporting film of the support device, and the pressure on the inner liner is reduced. In this way, when the inner liner is about to collapse, the pressure at the collapse point can be dispersed, which greatly improves the pressure limit of the inner liner collapse, helps to reduce the collapse of the inner liner during the winding process, and maintains the shape of the inner liner. At the same time, due to the bearing capacity of the frame structure of the support device, the inner liner can also maintain its shape well during the winding process, preventing the collapse phenomenon during the winding process.

[0031] 2. The method for maintaining the inner liner of a high-pressure hydrogen storage bottle proposed in the present invention has the obvious advantages of simple process, low cost and good collapse resistance.

[0032] 3. The supporting device used in the present invention has a simple and ingenious structure. It is rod-shaped in normal state, which is convenient for storage and transportation. In working state, it is subjected to tensile load, the structure unfolds, and the supporting film contacts the inner liner of the hydrogen storage bottle to assist the inner liner in bearing the load. When the inner liner is about to collapse, the pressure at the collapse point can be dispersed, which greatly improves the pressure limit of the inner liner collapse, helps to reduce the collapse of the inner liner during the winding process, and maintains the shape of the inner liner. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 The supporting device is retracted into a rod state;

[0034] Figure 2 is a schematic diagram of an embodiment;

[0035] Figure 3 This is a graph showing the collapse performance test results.

[0036] The reference numerals are as follows:

[0037] 1-support film, 2-holding rod, 3-frame connecting assembly, 4-body supporting member, 41-lumbar bar one, 42-lumbar bar two, 43-bottom bar one, 5-push rod, 6-connecting member; 7-fiber winding layer, 8-inner liner. DETAILED DESCRIPTION

[0038] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0039] According to the structure of the current IV type hydrogen storage bottle, the present invention designs the following Figure 1 and Figure 2 The support device shown includes a gripping rod, two pushing assemblies, a control assembly, a supporting film and a frame connecting assembly. The frame connecting assembly is coaxially fixed on the gripping rod, including 12 body supporting members (a total of 6 groups of body supporting members), each of which is an isosceles triangle, including waist bar 1, waist bar 2 and bottom bar 1 with ends hinged to each other; all body supporting members are fixedly arranged on the gripping rod in sequence through the same connecting member along the circumference, and are symmetrically arranged in groups of two relative to the gripping rod; the bottom bars 1 of all body supporting members are arranged parallel to each other. The supporting film is bonded to the outer peripheral surface of the frame connecting assembly. The pushing assembly includes a push rod and a motor. The middle parts of the push rods of the two pushing assemblies are vertically arranged on the gripping rod, respectively located above and below the connecting member, and the two ends of the push rod located above are respectively slidably arranged on the waist bar 1 of one group of symmetrically arranged body supporting members, and the two ends of the push rod located below are respectively slidably arranged on the waist bar 2 of one group of symmetrically arranged body supporting members; the length of the push rod is less than the diameter of the inlet of the inner tank of the IV-type hydrogen storage bottle, so that the push rod can enter and exit the inlet of the inner tank easily. The two ends of the upper push rod and the lower push rod can be slidably connected with different symmetrical body supports. In order to make the thrust more uniform, an umbrella-shaped push rod can also be used, which is slidably connected with 6 groups of body supports respectively. The umbrella-shaped push rod is composed of six rods located in the same horizontal plane and concentric with the center point. The angle between the adjacent rods of these six rods is 30°. The control component controls the push component to slide up and down along the gripping rod, driving the frame connection component to contract and expand. The control element (the existing control element can be used) controls the start and stop of the motor, and the push rod slides up and down along the gripping rod under the action of the motor.

[0040] Example 1

[0041] The inner liner of the hydrogen storage tank includes an outer layer and a barrier layer, and the barrier layer is attached to the inner surface of the outer layer. The outer layer is made of the following components: a copolymer of nylon 66 and nylon 1212 (monomer ratio is 2:1), 2% of a modified substance; wherein the modified substance includes 50% of a polyolefin elastomer, 25% of maleic anhydride and 25% of ethylene propylene diene rubber (by weight). The barrier layer 3 is made of the following components: an aqueous solution of polyvinyl alcohol with a solid content of 8% (molecular weight of 22,000).

[0042] The copolymer of nylon 66 and nylon 1212 (monomer ratio of 2:1) is blow molded to form the outer layer 1; then the barrier layer 3 is applied to the inner surface of the outer layer 1, with a coating amount of 1g / ㎡, and then aged in a 45℃ aging chamber for 5h to obtain a hydrogen storage tank liner sample. Subsequently, the above-mentioned support device is sent into the liner from the inlet in a contracted state, and the control unit controls the motor to drive the push rod to slide toward the connecting part. The support device expands in volume when it is deformed and stretched, and adapts to the structure of the hydrogen storage bottle liner, and supports the inner surface of the liner closely.

[0043] The above-mentioned supporting device is a negative Poisson's ratio structure. In the contracted state, it is rod-shaped, which is convenient for entering and exiting the inner liner entrance. In the expanded state, it is compatible with the inner liner structure in this embodiment. The supporting film is circumferentially wrapped around the outside of the frame connecting component and can change with the changes of the connecting component. When the connecting machine component is expanded, the supporting film is expanded accordingly, and is tightly attached to the inner surface of the inner liner to support the inner liner. Especially during the winding process of the inner liner, it can reduce the pressure at the contact point, disperse the pressure at the collapsed point, and increase the pressure limit of the collapse of the inner liner.

[0044] The specific structure of the supporting device can be adaptively adjusted according to the shape of the liner, not limited to Figure 1 and Figure 2 The structure in .

[0045] Comparative Example 1

[0046] Similarly, the inner liner of the hydrogen storage tank includes an outer layer 1 and a barrier layer 3, and the barrier layer 3 is attached to the inner surface of the outer layer 1. The outer layer 1 is made of the following components: a copolymer of nylon 66 and nylon 1212 (monomer ratio is 2:1), 2% of a modified substance; wherein the modified substance includes 50% of a polyolefin elastomer, 25% of maleic anhydride, and 25% of ethylene propylene diene monomer rubber (by weight). The barrier layer 3 is made of the following components: an aqueous solution of polyvinyl alcohol with a solid content of 8% (molecular weight of 22,000).

[0047] The copolymer of nylon 66 and nylon 1212 (monomer ratio is 2:1) is blow molded to form the outer layer 1; then the barrier layer 3 is applied to the inner surface of the outer layer 1 with a coating amount of 1 g / ㎡. After coating, it is aged in a 45°C aging chamber for 5 hours to obtain a hydrogen storage tank liner sample.

[0048] In order to verify the feasibility of the inner liner support method of the present invention, the present invention conducted the following collapse performance test on the inner liner samples of Example 1 and Comparative Example 1:

[0049] The prepared example liner and the comparative example liner were wound without upper limit according to the fiber winding method and speed described in the international standard ISO / DIS15869:2009 until the sample collapsed and the winding was stopped, and the thickness of the winding layer at this time was recorded, such as Figure 3As shown, the winding thickness of the liner with the support device involved is nearly twice the winding thickness of the liner without the support device.

[0050] When the inner liner retaining method of the present invention is used to prepare a hydrogen storage bottle, the process is as follows:

[0051] 1. Make the inner liner by injection molding;

[0052] 2. After the supporting device is sent into the inner liner in a contracted state, the supporting device is unfolded to closely adhere to the inner surface of the inner liner and provide support;

[0053] 3. Start to wrap the adsorbent material (i.e. fiber yarn pre-impregnated with resin) on the outer surface of the liner;

[0054] 4. After winding, shrink and remove the support device;

[0055] 5. Make the outer gas cylinder and complete the preparation of the hydrogen storage bottle.

[0056] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should be included in the protection scope of the present invention.

Claims

1. A method for maintaining the inner liner during the manufacturing process of a type IV hydrogen storage bottle, characterized in that: Before the inner liner of the IV type hydrogen storage bottle is wrapped with the adsorbent material, the support device in a contracted state is extended into the inner liner, stretched and expanded to closely adhere to the inner surface of the inner liner for support; The supporting device is a device with a negative Poisson's ratio structure. When it is contracted, it is rod-shaped, and when it is deformed and stretched, its volume expands to an unfolded state, which is compatible with the inner liner structure of a Type IV hydrogen storage bottle.

2. The method for maintaining the inner liner during the manufacturing process of the IV type hydrogen storage bottle according to claim 1, characterized in that: The supporting device comprises a holding rod, a pushing assembly, a control assembly, a supporting film and a frame connecting assembly; The frame connection assembly is coaxially fixedly arranged on the gripping rod; The supporting film is bonded to the outer peripheral surface of the frame connection assembly; The middle part of the pushing assembly is slidably connected to the holding rod, and the end part is slidably connected to the frame connecting assembly; The control component controls the pushing component to slide up and down along the holding rod, driving the frame connecting component to contract and expand.

3. The method for maintaining the inner liner during the manufacturing process of the IV type hydrogen storage bottle according to claim 2, characterized in that: The frame connection assembly includes N body support members, wherein N is an even number not less than 8; Each body support is in the shape of an isosceles triangle, and includes a waist bar 1, a waist bar 2 and a bottom bar 1, the ends of which are hinged to each other; all body support members are fixedly arranged on the gripping bar in sequence through the same connecting member along the circumferential direction, and are arranged symmetrically relative to the gripping bar in groups of two; the bottom bars 1 of all body support members are arranged parallel to each other; The pushing assembly includes a push rod and a motor; The middle parts of the push rods of the two push assemblies are vertically arranged on the gripping rod, respectively located above and below the connecting member, and the two ends of the push rod located above are respectively slidably arranged on one group of symmetrically arranged body support member waist bar 1, and the two ends of the push rod located below are respectively slidably arranged on one group of symmetrically arranged body support member waist bar 2; the length of the push rod is less than the diameter of the inlet of the inner liner of the IV type hydrogen storage bottle; The control element is used to control the start and stop of the motor, and the push rod slides up and down along the grip rod under the action of the motor; The supporting film is bonded to the outer peripheral surface of the frame connection assembly along all the bottom bars.

4. The method for maintaining the inner liner during the manufacturing process of the IV type hydrogen storage bottle according to claim 3, characterized in that: The N is 12.

5. A method for making a type IV hydrogen storage bottle, characterized in that: Before the inner liner is wrapped with the adsorbent material, the support device in a contracted state is extended into the inner liner, stretched and unfolded to be close to the inner surface of the inner liner for support; after the adsorbent material is wrapped, the support device is contracted and taken out; The supporting device is a device with a negative Poisson's ratio structure. When it is contracted, it is rod-shaped. When it is deformed and stretched, its volume expands to an open state, which is compatible with the inner liner structure of a Type IV hydrogen storage bottle.

6. The method for making a type IV hydrogen storage bottle according to claim 5, characterized in that: The supporting device comprises a holding rod, a pushing assembly, a control assembly, a supporting film and a frame connecting assembly; The frame connection assembly is coaxially fixedly arranged on the gripping rod; The supporting film is bonded to the outer peripheral surface of the frame connection assembly; The middle part of the pushing assembly is slidably connected to the holding rod, and the end part is slidably connected to the frame connecting assembly; The control component controls the pushing component to slide up and down along the holding rod, driving the frame connecting component to contract and expand.

7. The method for making a type IV hydrogen storage bottle according to claim 6, characterized in that: The frame connection assembly includes N body support members, wherein N is an even number not less than 8; Each body support is in the shape of an isosceles triangle, and includes a waist bar 1, a waist bar 2 and a bottom bar 1, the ends of which are hinged to each other; all body support members are fixedly arranged on the gripping bar in sequence through the same connecting member along the circumferential direction, and are arranged symmetrically relative to the gripping bar in groups of two; the bottom bars 1 of all body support members are arranged parallel to each other; The pushing assembly includes a push rod and a motor; The middle parts of the push rods of the two push assemblies are vertically arranged on the gripping rod, respectively located above and below the connecting member, and the two ends of the push rod located above are respectively slidably arranged on one group of symmetrically arranged body support member waist bar 1, and the two ends of the push rod located below are respectively slidably arranged on one group of symmetrically arranged body support member waist bar 2; the length of the push rod is less than the diameter of the inlet of the inner liner of the IV type hydrogen storage bottle; The control element is used to control the start and stop of the motor, and the push rod slides up and down along the grip rod under the action of the motor; The supporting film is bonded to the outer peripheral surface of the frame connection assembly along all the bottom bars.

8. The method for making a type IV hydrogen storage bottle according to claim 7, characterized in that: The N is 12.

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