KR102429178B1 - High-pressure tank having curved-shaped liner - Google Patents

Abstract

The present invention relates to a high-pressure container, comprising: a high-pressure container including a liner and a composite layer for reinforcing an outer circumferential surface of the liner, the high-pressure container comprising: a cylinder part formed along an axial direction of the high-pressure container; and a dome part fastened to both ends of the cylinder part to form the high-pressure container, wherein the diameter of the liner provided in the cylinder part is different along the axial direction.

Description

High-pressure tank having curved-shaped liner

The present invention relates to a high-pressure vessel that can be mounted in a fuel cell system, specifically, a liner forming a high-pressure vessel, and a composite layer that can be wound according to the shape of the liner and the region of the liner among the composite layers that can be wound on the outer circumferential surface of the liner. is about the type of

In general, a fuel cell system includes a fuel cell stack that generates electric energy, a fuel supply system that supplies fuel (hydrogen) to the fuel cell stack, and an air supply that supplies oxygen in the air, which is an oxidizing agent required for an electrochemical reaction, to the fuel cell stack. system, and a heat and water management system that controls the operating temperature of the fuel cell stack.

High-pressure compressed hydrogen of about 700 bar is stored in the hydrogen tank provided in the fuel supply system, that is, the hydrogen supply system, and the stored compressed hydrogen is turned on/off by the high-pressure regulator mounted at the inlet of the hydrogen tank. After being discharged to the high-pressure line, the pressure is reduced through the starting valve and the hydrogen supply valve and supplied to the fuel cell stack.

At this time, a high-pressure gas is used as fuel (hydrogen), and therefore, a gas storage container is required to store and discharge the gas as necessary. In particular, since gas has a low storage density in the container, it is efficient to store it at a high pressure, but has a disadvantage in that it is exposed to the risk of explosion due to the high pressure. In particular, since an alternative fuel gas vehicle has a limited mounting space for its storage container, maintaining the storage pressure at a high pressure and securing safety is the core of the technology.

Therefore, in the case of a composite container among these fuel gas storage containers, the outer shell must be reinforced with a fiber-reinforced composite material with high specific strength and specific stiffness to withstand the high internal pressure of hydrogen gas, and a liner that maintains gas tightness is inserted inside. . In detail, liners having two hemispherical shapes are bonded to both ends to constitute one storage container.

In addition, the storage container for gas, particularly hydrogen, is divided into types according to the material of the liner, and the container in which a metal liner such as aluminum is inserted is classified as Type 3, and the container in which the high-density polymer is inserted is classified as Type 4. Type 3 is relatively stable, but expensive, and has poor fatigue resistance, but Type 4 container is relatively inexpensive and has excellent fatigue resistance, but has stability problems such as poor hydrogen leakage and permeation resistance.

In particular, since high stress is generated along the circumferential direction in the cylindrical cylinder part formed in the center of the high-pressure container, the structure of the composite layer that withstands the stress by winding the cylinder part of the high-pressure container, and the weight while resisting the stress There is a technical need for reducing the weight.

US published patent US 2002-0088806 Japanese registered patent JP 2004-176898

In the case of a conventional high-pressure container, the composite material is wound at a low angle to the outside of the liner around the boss formed at both ends of the high-pressure container to form a helical layer, and the composite material is formed outside the liner of the cylinder part formed in the center of the high-pressure container at a high angle. A hoop layer was formed to be wound with However, in this case, pores may occur at the boundary between the hoop layer and the helical layer. Furthermore, it was difficult to guarantee the durability of the high-pressure vessel uniformly with respect to the stress in various directions applied to the high-pressure vessel. Therefore, in the present invention, the diameter of the liner formed in the cylinder portion of the high-pressure vessel is set differently, and preferably, the diameter of the liner at the center of the cylinder portion is formed to be the smallest, that is, the cylinder portion is shaped like a peanut or an hourglass. The center of the cylinder part is most concave, and as the hoop layer is wound and filled between the imaginary straight line connecting both ends of the cylinder part and the liner of the concave cylinder part, the weight of the composite layer is lightened while durability against stress. It provides a structure that can increase

According to an embodiment of the present invention for achieving the above object, in a high-pressure container including a liner and a composite layer for reinforcing the outer circumferential surface of the liner, the high-pressure container is a cylinder part formed along the axial direction of the high-pressure container. ; and a dome part fastened to both ends of the cylinder part to form the high-pressure container, wherein the diameter of the liner provided in the cylinder part is different along the axial direction.

In addition, there is provided a high-pressure container having the smallest diameter of the liner at the center of the cylinder part among the different diameters of the liner provided in the cylinder part.

In addition, there is provided a high-pressure container in which the composite material layer is wound on the outer peripheral surface of the liner.

In addition, the composite layer provides a high-pressure vessel including a hoop layer and a helical layer.

In addition, the high-pressure container is provided in which the hoop layer is laminated on an outer circumferential surface of the liner formed in the cylinder part, and the diameter of the cylinder part is constant along the axial direction as the hoop layer is laminated.

In addition, the composite layer formed closest to the liner provides a high-pressure vessel that is a hoop layer.

In addition, the composite layer provides a high-pressure vessel formed by alternately stacking the hoop layer and the helical layer.

In addition, the hoop layer provides a high-pressure vessel formed only in the cylinder portion.

In addition, the thickness of the hoop layer provides the thickest high-pressure vessel in the center of the cylinder part.

In addition, the thickness of the hoop layer provides the thinnest high-pressure vessel at both ends of the cylinder part.

Through the above-described problem solving means, the present invention provides the following effects.

According to the present invention, the stress acting on the cylinder portion of the high-pressure vessel can be reduced. Therefore, for the same safety standard, the cylinder part of the high-pressure vessel can secure a larger safety margin value, and can be more robust against stress.

In addition, according to the present invention, even if the same amount of the composite material is used, the maximum stress that can be endured in the cylinder part of the high-pressure vessel increases, so that the performance efficiency of the tank can be increased compared to the amount used.

In addition, according to the present invention, since a step does not occur at the interface where the hoop layer and the helical layer are wound, that is, at the end of the hoop layer, the formation of pores (gaps) that may occur during winding can be fundamentally prevented.

1 is a view showing the components and coupling relationships constituting the high-pressure vessel.
2 is a view showing a high-pressure vessel including a cylinder portion, a dome portion and a conversion point.
3 is a view showing a general embodiment of the high-pressure vessel.
4 is a diagram illustrating a shape of a liner according to an embodiment of the present invention.
5 is a diagram illustrating a high-pressure vessel including a liner having a curved shape and a composite layer on an outer circumferential surface of the liner as an embodiment of the present invention.
6 is a view including an enlarged view of area 'A' in FIG. 5 as an embodiment of the present invention.
7 is a graph showing the stress distribution of a general high-pressure vessel.
8 is a graph showing the stress distribution of the high-pressure vessel according to the present invention.
9 is a graph showing the comparison of the efficiency of the present invention and a general high-pressure vessel at the same point.

Hereinafter, an embodiment of the present invention will be described in more detail with reference to the accompanying drawings. Embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be construed as being limited to the following embodiments. This embodiment is provided to more completely explain the present invention to those of ordinary skill in the art.

In addition, terms such as "...unit", "...unit", "...module", etc. described in the specification mean a unit that processes at least one function or operation, which includes hardware or software or hardware and It can be implemented by a combination of software.

A fuel cell system mounted on a vehicle largely consists of a fuel cell stack that generates electrical energy, a fuel supply device that supplies fuel (hydrogen) to the fuel cell stack, and a fuel cell stack that supplies oxygen in the air, which is an oxidizing agent for electrochemical reactions, to the fuel cell stack. It consists of an air supply device, a cooling system that removes reaction heat of the fuel cell stack to the outside of the system, and controls the operating temperature of the fuel cell stack.

In the fuel supply system of the fuel cell system, a high-pressure vessel loaded with fuel may exist as a fuel storage tank. In the high-pressure vessel, hydrogen is preferably loaded and used as a fuel, and high-pressure hydrogen gas of about 700 bar can be stored inside the vessel.

Therefore, a high-pressure state by fuel or hydrogen can be maintained inside the high-pressure container, and the gas can pressurize the high-pressure container. In particular, when a leak or breakage occurs at one point of the high-pressure vessel, the internal high pressure is concentrated at one point, which can cause damage to the high-pressure vessel and an explosion accordingly. It is a very important element in a vehicle that can be equipped with a battery system.

In this regard, in order to stably store high-pressure fuel, preferably hydrogen, in the high-pressure vessel, a liner, specifically, a liner made of a plastic material, and a nozzle through which fuel can be injected or discharged at one end of the liner. A high-pressure vessel may be formed including the boss part 30 . Furthermore, it is a recent trend to use a type 4 high-pressure container in which the composite layer is formed by winding the outside of the structure in which the liner and the boss part 30 are combined with a carbon fiber composite.

Hereinafter, in the present specification, the dotted line indicated by 'X' in FIG. 1 is named as 'axis of high pressure vessel' or 'central axis of high pressure vessel' to describe one embodiment of the present invention. That is, the 'X' line in the drawing is a line drawn along the axial direction of the high-pressure vessel, and hereinafter, the axis of the high-pressure vessel may mean a line marked with 'X'.

1 and 2 show the structure of a general high-pressure vessel. 1, the high-pressure container includes a liner 10 provided at the innermost side, a boss portion 30 that can be fastened to one end of the liner 10, and a composite layer 20 that can be wound around the outer peripheral surface of the liner 10. may be included. Looking at the configuration of the composite material layer 20 wound on the outer circumferential surface of the liner 10 of the high-pressure vessel in detail, the composite material layer 20 may include a helical layer 23, a tube helical layer and a hoop layer 21. have. The composite layer 20 wound around the outer circumferential surface of the liner 10 may be formed by winding the composite material in the form of a ribbon several times.

The composite material is a continuous fiber having a predetermined width that can be formed in the form of a ribbon, and may be prepared in advance before winding, and may be wound on the outer circumferential surface of the liner 10 at a predetermined angle by a winding device. In detail, in a state in which the pre-injected liner is fixed, the winding device moves and forms a predetermined angle with respect to the liner, and then continuous composite fibers having a predetermined width have a predetermined tension on the outer circumferential surface of the liner 10 while It may be wound to form the composite layer 20 . That is, the composite material layer 20 may be formed as the composite material is wound and laminated in multiple layers, and the first layer wound on the outer circumferential surface of the liner 10 may be formed in contact with the outer circumferential surface of the liner 10 .

At this time, the helical layer 23, the tube helical layer, and the hoop layer 21 may be distinguished by the winding angle. Specifically, the helical layer 23, the tube helical layer, and the hoop layer 21 are the helical layer 23 wound at a low angle (preferably 5 degrees to 44 degrees) with respect to the central axis (X-ray) of the high-pressure vessel, As meaning a tube helical layer wound at a medium angle (preferably 45 degrees to 87 degrees) and a hoop layer 21 wound at a high angle, the high-pressure vessel, specifically, the liner 10, from the outer circumferential surface of the high-pressure vessel axis (X) It can be distinguished according to the angle at which the ribbon-shaped composite material is wound based on .

Furthermore, in the present invention, for convenience of explanation, the interface between the hoop layer 21 and the helical layer 23, that is, the interface between the outermost hoop layer 21 and the innermost helical layer 23, is a line shown in the cross-sectional view. may be referred to as a hoop layer line 22 , and a line indicated by the outermost helical layer 23 in the cross-sectional view may be referred to as a helical layer line 24 .

In addition, referring to FIG. 2 , the high-pressure vessel may include a dome part 100 and a cylinder part 200 , and a conversion point 300 at a point where the dome part 100 and the cylinder part 200 meet, that is, a switching point. ) may exist. In general, the cylinder part 200 may refer to a region extending in a cylindrical shape from the center of the high-pressure vessel, and the dome part 100 may refer to an area coupled to both ends of the cylinder part 200 in a hemispherical shape. That is, the part that can be formed extending along the axial direction (X) is the cylinder part 200, and the part that is formed in a hemispherical shape with a certain curvature and can be fastened to both ends of the cylinder part 200 is the dome part 100. . According to a conventional technique, since the cylinder part 200 of the high-pressure vessel may be formed in a cylindrical shape, the cylinder part 200 of the high-pressure vessel has a curvature only with respect to the diameter of the cylinder part 200, and the axis of the high-pressure vessel It may have a shape that does not have a curvature along the direction (X).

On the other hand, the conversion point 300 of the high-pressure vessel is a point where the cylinder part 200 and the dome part 100 come into contact, and in general, it may be a point where the high-pressure vessel starts to have a curvature along the axial direction (X). In detail, a portion where the high-pressure vessel begins to have a curvature that converges to a point along the axial direction (X) may be the conversion point (300). However, in one embodiment of the present invention, since the cylinder part 200, specifically the liner 10 of the cylinder part 200, may have a curvature along the axial direction (X) of the high-pressure vessel, hereinafter, in the present invention, The 'conversion point 300' may mean 'a point at which the curvature starts to gather at one point along the axial direction (X) of the high pressure vessel'.

On the other hand, FIGS. 1 and 2 are the same high-pressure container, and the high-pressure container is divided into a boss part 30, a liner 10, and a composite material layer 20 depending on the parts to be assembled, or a cylinder part 200 based on the shape thereof. ), the dome part 100 and the conversion point 300 can be distinguished. Hereinafter, in the present invention, based on the same concept, the terms 'liner 10', 'composite layer 20', 'cylinder part 200' and 'dome part 100' are adopted to provide an embodiment of the present invention. can be explained

In general, since the high-pressure vessel is filled with high-pressure fuel, preferably gas, therein, the high-pressure vessel is subjected to radial stress. Therefore, each point of the liner 10 receives a force applied in the radial direction from the center point of the high-pressure vessel, and in the dome portion 100 of the high-pressure vessel, winding the composite material at a low angle with respect to the axial direction (X) of the high-pressure vessel. It can be seen that the structure is the most capable of withstanding the force in the radial direction.

Similarly, in the cylinder part 200 of the high-pressure container, internal pressure may be applied in a radial direction from the center point of the high-pressure container, that is, along the circumferential direction of the cylinder part 200 . Therefore, it can be seen that winding the composite material having a certain width in a direction perpendicular to the axial direction (X) of the high-pressure vessel is the structure that can best withstand the pressure applied to the liner 10 and the high-pressure vessel.

However, from a material mechanics point of view, the stress in the circumferential direction of the cylinder part 200 of the high-pressure vessel, that is, in the vertical direction of the axial direction (X) of the high-pressure vessel, is two compared to the stress applied in the axial direction (X) of the high-pressure vessel. It may be more than double the size. Accordingly, in the cylinder unit 200 , the hoop layer 21 wound close to the vertical to the axial direction X of the high-pressure vessel is responsible for reducing the stress in the cylinder unit 200 in the circumferential direction of the high-pressure vessel. That is, the stress of the high-pressure vessel acts to a greater extent on the cylinder part 200 than on the dome part 100 , and in particular, since the stress acts intensively in the circumferential direction of the cylinder part 200 , the hoop layer 21 is the cylinder part of the high-pressure container. It can only be wound at (200). However, in principle, the hoop layer 21 , the tube helical layer and the helical layer 23 may be wound over the entire liner 10 , and different types of layers may be alternately stacked.

3 shows the structure of the liner 10 and the composite material wound on the liner 10, which can be generally employed in the field of high-pressure vessels. 3 is a view showing a state in which the hoop layer 21 is wound only on the cylinder part 200 of the high-pressure vessel, as described above. Referring to the enlarged view of part 'A' of FIG. 3, in part 'A' of FIG. 3, in a state in which the diameter of the liner 10 of the cylinder part 200 is constant, the cylinder part 200 and the liner 10 When the hoop layer 21 is stacked on the outer circumferential surface of , a step may occur at the interface between the hoop layer 21 and the helical layer 23 , that is, at the hoop layer line 22 . That is, the hoop layer and the helical layer may not be in close contact with each other in the step generation region B of FIG. 3 .

This phenomenon may occur as the hoop layer 21 is wound only on the cylinder part 200 and the hoop layer 21 and the helical layer 23 are wound at different angles. However, when a step occurs, it is not suitable to withstand the stress of the high-pressure vessel evenly, and the defect rate during manufacturing significantly increases, and the need to solve these problems is constantly being raised.

Therefore, in the present invention, while winding the hoop layer 21 only on the cylinder unit 200, the liner 10 provided in the cylinder unit 200 so as not to cause a step difference between the hoop layer 21 and the helical layer 23. is to be formed to have a different diameter along the axial direction (X), that is, to form the liner 10 of the cylinder part 200 to have a curvature along the axial direction (X), and below with reference to the drawings, As a preferred embodiment of the present invention, the structure of the high-pressure vessel including the curved liner 10 will be described in detail.

4 is a view showing the shape of the liner 10 according to an embodiment of the present invention. The liner 10 in the present invention may have a peanut shape or an hourglass shape. That is, one liner 10 may be formed including the hemispherical dome portions 100 at both ends and the mortar-shaped cylinder portions 200 concave inwardly in the center. Preferably, in the liner 10 according to an embodiment of the present invention, the diameter of the liner 10 provided in the cylinder part 200 may be different from each other along the axial direction (X) of the liner 10 . have.

According to a preferred embodiment, the diameter of the liner 10 of the cylinder unit 200 in the present invention may be the smallest in the center of the high-pressure vessel. That is, the liner 10 may be formed to be most concave inside the liner 10 in the central portion of the high-pressure vessel. Furthermore, the liner 10 may have a symmetrical shape with respect to the axial direction (X) or an axis perpendicular to the axial direction (X) of the high-pressure vessel. That is, in the cross-sectional view of the liner 10 , the shape of the liner 10 may be symmetric with respect to the X-axis or an axis perpendicular to the X-axis.

Meanwhile, FIG. 5 is a view showing an embodiment of the present invention, wherein the composite material layer 20 is formed by winding the composite material on the outer circumferential surface of the curved liner 10 . According to FIG. 5 , the hoop layer 21 can be wound only on the liner 10 of the cylinder part 200 , and preferably, since the liner 10 of the cylinder part 200 has different diameters, the cylinder part (200) A greater amount of composite material is deposited in the concave region of the liner 10 so that the hoop layer 21 can be wound.

5, since the liner 10 is most concavely formed inside the liner 10 in the central portion of the high-pressure container, the thickness of the hoop layer 21 wound around the outer circumferential surface of the liner 10 is the same as the high-pressure container. of the central portion, preferably the center of the cylinder portion 200 may be formed to be the thickest. At the same time, according to the embodiment of FIG. 5 , the thickness of the hoop layer 21 wound around the outer circumferential surface of the liner 10 is the end of the cylinder part 200 of the high-pressure vessel, that is, the hoop layer 21 stacked at the conversion point 300 . ) may be formed to the thinnest thickness.

FIG. 6 is an enlarged view of area 'A' of FIG. 5 and shows the stacking relationship between the liner 10, the hoop layer 21, and the helical layer. In a preferred embodiment of the present invention, the outer peripheral surface of the liner 10 The hoop layer 21 may be laminated only on the liner 10 of the cylinder part 200 which is a part of the . According to a more preferred embodiment, the hoop layer 21 is wound more in the concave region of the liner 10 of the cylinder unit 200, so that the cylinder unit 200 on which the hoop layer 21 is wound has a constant diameter. A cylindrical shape may be achieved. That is, the hoop layer 21 wound on the outer circumferential surface of the liner 10 of the cylinder unit 200 can adjust the amount of the composite material wound according to the degree to which the liner 10 is concavely formed inside the liner 10, Accordingly, in the high-pressure container after the hoop layer 21 is finished winding, the outer diameter of the cylinder part 200 may be uniformly formed.

Referring again to FIG. 6 , according to an embodiment of the present invention, the type of the composite material layer 20 that is wound in direct contact with the outer circumferential surface of the liner 10 may be the hoop layer 21 . More preferably, according to an embodiment of the present invention, the hoop layer 21 is formed on the outer circumferential surface of the liner 10 , and the helical layer 23 may be wound around the hoop layer 21 .

Furthermore, according to another exemplary embodiment, in the composite layer 20 wound around the outer circumferential surface of the liner 10 , the hoop layer 21 and the helical layer 23 may be alternately stacked. Preferably, when the hoop layer 21 and the helical layer 23 are alternately stacked, the innermost layer of the composite material layer 20 in contact with the liner 10 is the hoop layer 21 and the composite material layer 20 in contact with the outside. The outermost layer of may be formed of a helical layer (23).

Meanwhile, FIG. 7 is a graph showing the structure of a high-pressure vessel in which the central part of the high-pressure vessel is cut and the normalized stress distribution thereof in a high-pressure vessel having a general structure. Looking at the stress distribution graph of the cylinder part 200 , the center is the center of the high-pressure vessel and means the center of the cylinder part 200 , and as the distance from the center to the dome part 100 is increased, the stress applied to the hoop layer 21 . It can be seen that this decreases. That is, in the graph, not only the stress applied to the cylinder part 200 and the dome part 100 by the gas pressure inside the high-pressure vessel is not the same, but also the stress applied according to the distance from the center in the cylinder part 200. You can see the sizes are different. In detail, the closer the center of the high-pressure vessel, preferably the center of the cylinder part 200, the greater the stress applied to the high-pressure vessel. Such analysis results show that in order to increase the strength of the high-pressure vessel, the hoop layer 21 should be concentrated and reinforced at the center of the cylinder part 200 , specifically, the cylinder part 200 .

Furthermore, FIG. 8 is a graph showing the stress distribution of the cylinder part 200 to which the liner 10 according to an embodiment of the present invention is applied, in order to compare it with the stress distribution graph of FIG. 7 . 8 shows the stress distribution of the cylinder part 200 according to the prior art and the present invention, it can be seen that the stress level acting on the cylinder part 200 is lowered according to an embodiment of the present invention. Therefore, according to an embodiment of the present invention with respect to the safety standard of the same high-pressure vessel, it is possible to secure a larger value of the safety margin.

9 is a graph showing the efficiency of a high-pressure vessel when an embodiment of the present invention is applied. A point having a stress of about 1.0 before applying the proposed structure to a point having a stress of about 0.86 after application of an embodiment according to the present invention is obtained. FIG. 9 shows the reciprocal of the stress value as a graph. Comparing the numerical value of the high-pressure vessel efficiency, it can be seen that the efficiency increases by about 18% when an embodiment according to the present invention is adopted.

In summary, the core idea of the present invention is that the diameters of the liners formed on the cylinder part are different from each other, and after the hoop layer 21 is wound, the hoop layer is wound so that the cylinder part has a certain diameter, so that the concave area of the liner is formed. It is characterized in that the hoop layer can be wound more and it is possible to prevent a step difference between the hoop layer and the helical layer 23 from occurring. In particular, the diameter of the liner may be formed the smallest at the center of the high-pressure vessel, that is, at the center of the cylinder part. It should be noted that there is a feature of the present invention that the

In addition, although the embodiments of the present invention have been described and described, those of ordinary skill in the art can add, change, delete or It will be said that the present invention can be variously modified and changed by addition and the like, and this is also included within the scope of the present invention.

Furthermore, when it is determined that a detailed description of a well-known function or configuration may unnecessarily obscure the gist of the present invention in describing the embodiments of the present invention, the detailed description thereof is omitted. And the terms used in the above are terms defined in consideration of functions in the embodiment of the present invention, which may vary according to the intention or custom of the user or operator. Therefore, the definition should be made based on the content throughout this specification. Accordingly, the detailed description of the present invention is not intended to limit the present invention to the disclosed embodiments, and the appended claims should be construed as including other embodiments.

10 : liner
20: composite material layer
21: hoop layer
22: hoop layer line
23: helical layer
24: helical layer line
30: boss
100: dome part
200: cylinder part
300: conversion point
B: Step area
X: The shaft of the high-pressure vessel and the shaft of the cylinder

Claims (10)

In the high-pressure container comprising a liner and a composite layer for reinforcing the outer peripheral surface of the liner,
The high-pressure vessel includes a cylinder portion formed along the axial direction of the high-pressure vessel; and a dome portion fastened to both ends of the cylinder portion to form the high-pressure vessel,
The diameter of the liner provided in the cylinder part is formed to be different along the axial direction,
Among the different diameters of the liner provided in the cylinder part, the diameter of the liner is the smallest at the center of the cylinder part based on the axial direction,
A composite layer including a hoop layer and a helical layer is wound on the outer circumferential surface of the liner, wherein the hoop layer of the composite layer is laminated only on the outer circumferential surface of the liner provided in the cylinder part,
The outer diameter of the cylinder part on which the hoop layer is laminated has a constant size along the axial direction,
A high-pressure container in which a composite layer including the helical layer is laminated on an outer circumferential surface of the cylinder part whose outer diameter is constant as the hoop layer is stacked. delete delete delete delete The high-pressure vessel according to claim 1, wherein the composite layer formed closest to the liner is a hoop layer. The high-pressure vessel according to claim 1, wherein the composite layer is formed by alternately stacking the hoop layer and the helical layer. The high-pressure vessel according to claim 1, wherein the hoop layer is formed only on the cylinder part. The high-pressure vessel according to claim 1, wherein the hoop layer has the thickest thickness at the center of the cylinder part. The high-pressure vessel according to claim 1, wherein the hoop layer has the thinnest thickness at both ends of the cylinder part.

Images