RU2606301C2 - Accumulator for hydrogen storage in bound state and accumulator cartridge - Google Patents

Abstract

FIELD: energy.

SUBSTANCE: invention relates to hydrogen power engineering and can be used for storage, transportation and distribution (supply) of hydrogen in fuel cells and other power plants. Hydrogen accumulator structure is based on the concept of modular implementation of a hydrogen accumulator in the form of a system of easily replaceable during operation cartridges containing hydrogen in the bound state in a hydrogen-saturated film coating applied on a metal foil tape, which can be folded then into a spiral or another form with a shape providing high degree of compaction. For fixation of the cartridges a system of heat exchange elements with bee cells geometry is used, and a device for extracting hydrogen of the accumulator has a system of needles/knives for depressurization of charged (hydrogen-charged) cartridges after their initial loading into the accumulator. To obtain the possibility of using fast-response time hydrogen thermal desorption modes as the foil material selected are metals or alloys with high ohmic resistance, ends of the foil are connected with electric contacts on the metal end of the cartridge connected with a controlled voltage source. Fast-response time hydrogen thermal desorption is performed by ohmic heating the foil with high resistance, that provides new possibilities for programming hydrogen release parameters.

EFFECT: technical result of using the invention are elimination of explosion hazard in emergency situations, higher bulk density of hydrogen in the accumulator and improved operating performances, including minimization of hydrogen release transient modes time down to 0,1 sec, as well as of pressure level in the accumulator at hydrogen supply to consumers.

8 cl, 3 dwg

Description

Technical field

The invention relates to the field of hydrogen energy and can be used for storage, transportation and distribution (supply) of hydrogen in fuel cells and other power plants.

State of the art

One of the most important tasks of hydrogen energy is the creation of technically and economically viable batteries for storing hydrogen. Moreover, according to the requirements of the International Energy Agency, storage systems must contain at least 5 wt. % of hydrogen and emit it at a temperature not higher than 373 K. In addition, one of the decisive criteria for choosing an accumulation system is the economic feasibility of its use.

Currently, physical methods of hydrogen storage (in the form of a cryogenic liquid or compressed gas) and chemical or physico-chemical methods (adsorption, absorption, chemical reaction, for example, forming metal hydrides with hydrogen (metal hydrides) are being developed.

Known solutions using physical methods [RF Patent No. 2498151, 2013; RF patent No. 2346202, 2009; RF patent No. 2440290, 2012; International application WO 2008/019414, publ. 02.21.2008, etc.], in which it is proposed to accumulate hydrogen under high pressure (up to several thousand atmospheres) in bundles of micro (nano) capillaries or in microspheres.

A known device and cartridge for storing compressed hydrogen gas [Patent US 8167122]. A device for storing compressed hydrogen gas includes a sealed housing having an exhaust pipe attached to the housing and equipped with an adjustable exhaust valve, a hydrogen evolution device configured to selectively release (release) hydrogen gas. Inside the sealed enclosure is a cartridge configured to store and store compressed hydrogen gas and comprising a housing and a prefabricated structure of two different types of microcontainers housed in the housing. The microcontainers are selected from at least one hollow micro-cylinder partially permeable to hydrogen having clogged ends and a plurality of hollow microspheres partially permeable to hydrogen. Microcontainers of one type differ from microcontainers of another type in the rate of hydrogen release from microcontainers.

The microcontainer assembly includes a first part having a tubular shape and a second part having a cylindrical shape and located inside the cavity of the first part. According to one embodiment of the invention, the first part consists of a plurality of micro cylinders tightly packed and axially placed inside the first part, and the second part includes many microspheres tightly packed and filling the cylindrical volume of the second part.

Hollow microcylinders can be made of a material having relatively low permeability with respect to hydrogen at temperatures below 20-30 ° C and more than 10 times greater permeability at temperatures above 70-90 ° C. The microspheres can be made of a material having a relatively low permeability with respect to hydrogen at a temperature of 50-70 ° C and more than 10 greater permeability at a temperature above 200-250 ° C.

The cartridge for storing and storing hydrogen can be filled with hydrogen gas by placing the cartridge in conditions with a high temperature (200-500 ° C) and a pressure (1-300 atm.) Of hydrogen (for example, in an autoclave).

The disadvantage of this device is the uneven heating of the micro-containers in the cartridge, which does not allow programmed hydrogen evolution. The manufacture of cartridges, including hydrogenation by the Sievert method, is laborious and inefficient, the latter being possible only if special equipment is available in stationary conditions. The design of the device and cartridge does not allow rapid replacement of the latter. In addition, all physical methods are not cost effective, convenient and safe.

A hydrogen storage device is known in which hydrogen is accumulated in the mass of aluminosilicate (halloydium, halloysite) applied in the form of a monolayer on a substrate placed (placed) in an airtight container, and the substrate material may be stainless steel or polymer films [Patent US 7425232, Hydrogen storage apparatus comprised of halloysite]. During the hydrogenation process, a part of the sorbent material is transformed into hollow rods with various aspect ratios (with a diameter of about 20 nm and a length of 200 ÷ 500 nm), which contain part (1 ÷ 5)% of the hydrogen stored in the storage. Various methods (electrostatic, centrifugal, filter, etc.) are used to separate the rods from the aluminosilicate agglomerate, and the electrolytic method is used to apply them to the substrate.

The drive and its manufacturing method are difficult to implement and ineffective. In addition, like all physical methods of hydrogen storage, it is not economically efficient, convenient, and safe.

A device is known "A container for hydrogen and its isotopes and a cartridge for its equipment" [RF Patent No. 2221290, 2004], which allows to increase the rate of absorption and evolution of hydrogen by reducing filtration resistance. The device comprises a housing, inside of which, between cylindrical concentric mounted shells, cartridges are placed having a gas-permeable housing, in which a mixture of powder of a sorbent for hydrogen and a powder of heat-conducting material inert to hydrogen and a sorbent is placed with a volume fraction of powder of heat-conducting material from 0.3 to 0.5. The powder mixture is heated through the surface of the inner shell.

The disadvantage of this device is that the sorbent for gases is diluted with the material in a volume fraction of up to 0.5, which significantly reduces the indicator important for stand-alone and mobile storage devices - the volume fraction of accumulated hydrogen. In addition, the cartridges are installed in such a way that replacing them requires disassembling the entire device.

A device for storing and transporting hydrogen is known (RF Patent No. 2435098, 2011). The device comprises a housing with a hydrogen line, in which hydrogen accumulators, sorption elements and electric heaters are located, as well as a line for supplying a working medium in the form of a collector, where a coolant or refrigerant is used as a working medium, while the collector is connected to the working medium sources switching the coolant to the refrigerant. Hydrogen accumulators are located in capsules with gas-permeable shells, which are mounted on the collectors coaxially with the possibility of their replacement. Heat-conducting elements are installed inside the capsules, between which hydrogen accumulators are located.

Microspheres and (or) intermetallic alloys, which form stable solid compounds and / or lithium fulleride with gas, are used as a hydrogen accumulator. Heaters are installed around the capsules. Electric heaters are installed with the ability to independently control the temperature of each capsule. On the outer surface of the capsules can be installed infrared (IR) emitters.

When the capsules are heated, hydrogen is released from the microspheres, which enters the internal cavity of the tank (hydrogen line) through the porous wall of the capsule and is discharged to the consumer.

The disadvantages of the device are:

1) the use of sealed capsules (cartridges) with porous walls, which significantly limits both the rate of hydrogen evolution into the collector and the efficiency of hydrogenation of the active elements of the capsules;

2) the use of microspheres, dispersed and porous materials and (or) intermetallic alloys forming stable solid compounds with hydrogen and (or) lithium fullerides as active elements of capsules of capsules requires the use of low-efficiency gas saturation technology (Sievert method) under high pressure hydrogen (up to 300 atm.) Using special equipment in stationary conditions, which significantly reduces the economic efficiency of using the device;

3) the presence inside the device of numerous electric and infrared heaters, microspheres with hydrogen under high pressure significantly reduces the level of operational safety of the device and increases its size.

A common disadvantage of the known hydrogen storage systems is the high inertia of the hydrogen release process. On the other hand, for efficient operation of the vehicle, the start time for the release of hydrogen before reaching the full flow, as well as the times of transient conditions (10-90% or 90-0%) should not exceed 0.5 s.

The technical result of the invention is the elimination of the disadvantages of known hydrogen batteries: reducing explosiveness in emergency situations, improving their operational, technical and economic characteristics.

Disclosure of invention

This result is achieved by the fact that the design of the hydrogen accumulator is based on the concept of modular implementation of the hydrogen accumulator in the form of a system of axially arranged easily replaceable cartridges containing hydrogen in a bound state in a hydrogen-saturated film coating deposited on a metal foil tape, which can then be rolled into a spiral or another shape with a geometry that provides a high degree of compaction, which contributes to the achievement of high specific gravity in the battery. Due to the significantly lower binding energy hydrogen desorption occurs more easily in the film coating and at much lower temperatures (T _m ~ 500K for Ti) compared to monolithic metals and alloys (T _m ~ 700K) [W. Lisowski et al., Decomposition of thin titanium deuteride films; thermal desorption kinetics studies combined with microstructure analysis // Appl. Surface Science, 254 (9), (2008) pp. 2629-2637] with the simultaneous possibility of increasing the degree of saturation [E. Tal-

Gutelmacher et al., The effect of residual hydrogen on hydrogenation behavior of Ti thin film // Scripta Materialia 62 (2010) pp. 709-712].

To obtain the possibility of using hydrogen thermal desorption modes with low inertia, metals or alloys with high ohmic resistance are selected as the foil material, the ends of the foil are connected to the foil electric heating contacts on the metal end of the cartridge, which are connected to an adjustable voltage source. In this mode, thermal desorption of hydrogen is carried out by ohmic heating of the foil with high resistance. The mode of electrothermal desorption of hydrogen from the coating has a significantly lower inertia compared to the heating mode of the outer surface of the cartridge, which allows to achieve a delay time from the start of hydrogen release to achieve full flow, as well as the time of transitional modes (10-90% or 90-0%) ~ 0.1 s, which provides new opportunities for programming the parameters of hydrogen evolution and storage. To limit the long-term diffusion of hydrogen into the foil material, the latter is preliminarily coated with a hydrogen diffusion barrier in the form of a coating of nitrides (e.g., TiN), or oxides (e.g., TiO, Al ₂ O ₃ ), or thin films of Al, or W, or Mo, or Ta, or Cr, or Nb. A diffusion barrier is also applied to the cartridge body and its elements.

Brief Description of the Drawings

The presented graphic materials are for illustrative purposes only and are not limiting. It should be noted that the figures illustrating the device according to the present invention are given for clarity without observing the scale and proportions.

In FIG. 1 is a schematic cross-sectional view of a cylindrical embodiment of a replaceable hydrogen storage cartridge according to the present invention. The cartridge includes a housing 1 with an active element located inside it - a foil metal strip coated with hydrogen metal or composite rolled into a spiral 2, an end foil plug 3, a metal plug 4 with a thin-walled nozzle for evacuation 5 and contacts for electrical heating of the foil 6 for connecting the ends of the foil to a voltage source. The needle / knife 7 for opening the foil plugs of the cartridge before operating the latter is part of a device for hydrogen evolution.

The material of the cartridge case is a metal with good thermal conductivity, for example, aluminum coated in the form of a hydrogen diffusion barrier that prevents the long-term diffusion of hydrogen into the material.

In FIG. 2 shows an embodiment of a hydrogen storage device for a cylindrical battery case. The elements of the heat exchange system (9) of the hydrogen separation / filling device form a volume matrix for fixing cylindrical cartridges (8).

In FIG. 3 is a schematic cross-sectional view of a hydrogen storage device (battery) according to the present invention. The device includes a housing 10 having an easily removable cover 11, a hydrogen storage device 12 installed in the chamber 10 using fasteners (not shown), a hydrogen evolution device 13, a safety valve 14, a port for evacuating the chamber / hydrogen inlet 15, a pressure sensor 16, a regulator flow rate 17, flow meter 18, exhaust valve 19.

The shape of the housing 10 may be, for example, cylindrical. However, essentially any desired shape may be used. The housing 10 may be made of a suitable metal, plastic or composite material with a wall thickness capable of withstanding the stresses in the walls caused by gas pressure inside the housing 10 in the operating mode (up to ~ 10 atm.) And atmospheric pressure during preliminary evacuation.

The implementation of the invention

The key in the implementation of the invention is the use of the active elements of the cartridges - hydrogen-saturated film coatings deposited on a substrate using plasma sources in a hydrogen environment. The substrate is a thin metal (for example, stainless steel or metals and alloys with high ohmic resistance) foil tape coated with oxides or nitrides as a hydrogen diffusion barrier that limits the diffusion of hydrogen from the coating into the substrate, then coiled into an Archimedes spiral with a step that ensures the gap between adjacent turns. However, this does not limit the variety of possible tape shapes, selected in accordance with the requirements for the shape and size of the cartridge and / or battery (for example, plates or "honeycombs" from regular hexagons, etc.).

Hydrogenated tapes made in this way are threaded into axially arranged cylindrical cartridges (Fig. 1) and fixed (for example, by spiral guides in the end parts of the cartridge). The spiral geometry of the foil roll helps to reduce the deformation of the foil during thermal desorption of hydrogen by compensating for stresses on the free (not fixed) sections of the foil. The body material of the cartridge is a metal with high thermal conductivity (for example, Al), coated on both sides with hydrogen diffusion barriers. One of the vacuum tight end caps is made of foil (for example, stainless steel coated with a hydrogen diffusion barrier). Sealing is provided by microwelding or pressing.

Another vacuum tight end plug has a thin-walled nozzle for evacuating the cartridge after its manufacture and contacts foil electric heating to connect the ends of the foil to a voltage source during electrical heating of the foil from alloys with high resistance. After evacuating the cartridge, it is sealed by compressing the tube. Cartridges made in this way can be stored under normal conditions without any time limit [B.P. Tarasov et al., Problems of hydrogen storage and prospects of using hydrides for hydrogen storage // Russian Chemicals. Journal (2006), T. L, No. 6].

After opening the easily removable battery flange, the cartridges are inserted into the volumetric mechanical structure of the cartridge fixing formed by a system of heat exchange elements (channels) with the geometry of a honeycomb (Fig. 2), the chamber is sealed and evacuated air is pumped using a special port 15 (Fig. 3) to minimize impurities in desorbed hydrogen. After that, the system of needles / knives of the hydrogen evolution device is opened to open the foil end caps of the cartridges and the programmed heating of the cartridges by the heat carrier through the heat exchange elements and / or for transient conditions with a high rate of change of the hydrogen flow is activated, the foil is electrically heated by passing a current with a programmable value through it.

Manipulation control (evacuation, opening the cartridges, programmable heating of the cartridges by a heat exchange or electric heating system for programmable thermal desorption of hydrogen from the active elements of the cartridges or cooling the cartridges when refueling with hydrogen under pressure, adjusting the gas flow at the outlet) using the battery using the control system (in Fig. .3 not shown) based on data from the temperature sensors of the cartridges, pressure in the chamber, and a flow meter located in the chamber. The supply of hydrogen to the user at a given flow and its termination is carried out using the exhaust valve 19 (Fig. 3).

If it is necessary to quickly replace one, several or all of the cartridges, the pressure in the chamber is brought to atmospheric pressure by opening the safety valve 14 (Fig. 3), the easily removable cover 11 (Fig. 3) opens and a replacement is made. Such an opportunity significantly increases the autonomy of using the battery when the traditional refueling with hydrogen inlet under pressure is unavailable, and also increases the convenience in operation and maintenance.

The option of refueling (refueling) the drive with hydrogen after its full or partial generation requires only programmed inversion of the mode of the heat transfer system of the cartridges (switching the working environment of the system from the coolant to the refrigerant), i.e. the transition to cooling mode when the cartridges are saturated by injecting hydrogen under pressure through port 15 (Fig. 3).

T.O. the positive effects of using a device for storing hydrogen (battery) are the elimination of explosive hazards in emergency situations, increasing the bulk density of hydrogen in the drive and improving its operational and technical characteristics, including minimizing the transition time of hydrogen evolution to 0.1 s. The ability to control the pressure of desorbed hydrogen by programming the electrothermal effect on the sorbent elements of the cartridges makes it possible to minimize the pressure level in the storage ring when supplying hydrogen to the consumer.

The storage of hydrogen in a bound state in a hydrogen-saturated film coating applied to a metal foil tape helps to achieve high values of the specific density of hydrogen in the battery.

The design of the battery allows quick refueling (with spare cartridges) and refueling (both in the form of replacing cartridges and saturating the drive with hydrogen under pressure). The economic efficiency of manufacturing the active elements of the cartridges allows their single use with subsequent disposal.

Claims (8)

1. A battery for storing hydrogen in the form of metal hydrides or composites, comprising a sealed housing with a nozzle for hydrogen output with an adjustable exhaust valve, a safety valve, a port for evacuation / inlet and at least one easily removable end cap, while the storage unit is located inside the housing hydrogen, made in the form of a system of axially arranged hydrogen-containing cartridges, tightly packed in a volumetric mechanical structure of fixation, which allows quick extraction and cartridges, pressure and temperature sensors, a device for hydrogen evolution, including heat exchange elements with the ability to quickly switch the working medium to a coolant or refrigerant, characterized in that as a volumetric mechanical structure for fixing the cartridges, a system of heat exchange elements with the geometry of bee cells is used, and The device for hydrogen evolution has a system of needles or knives for depressurization of hydrogenated cartridges after their initial loading into the volumetric mechanical esky structure of fixation. 2. A battery cartridge for storing hydrogen in the form of metal hydrides or composites, respectively, containing a sealed housing with an active element, characterized in that the latter is made in the form of a metal foil deposited on the surface using plasma sources in a hydrogen medium with a film coating of hydrogenated metal or composite, respectively. 3. The cartridge according to claim 2, characterized in that the coating of hydrogenated metal or composite, respectively, is applied to both sides of the metal foil in the cartridge. 4. The cartridge according to paragraphs. 2, 3, characterized in that the foil is preliminarily coated with a hydrogen diffusion barrier in the form of a coating of nitrides, or oxides, or thin films of Al, or W, or Mo, or Ta, or Cr, or Nb. 5. The cartridge according to claim 4, characterized in that the foil has the shape of an Archimedes spiral with a step sufficient to form a gap between the turns of the tape. 6. The cartridge according to claim 5, characterized in that metals or alloys with high ohmic resistance are selected as the foil material, and the ends of the foil have electrical leads. 7. The cartridge according to claim 6, characterized in that a hydrogen diffusion barrier in the form of a coating of nitrides, or oxides, or thin films of Al, or W, or Mo, or Ta, or Cr, or Nb. 8. The cartridge according to claim 7, characterized in that the metal housing of the cartridge containing the foil has vacuum tight end caps, one of which is made of metal or composite foil with low hydrogen permeability, achieved by coating - a hydrogen diffusion barrier, and the second metal - has a thin-walled nozzle for evacuating the cartridge after its manufacture and electrical contacts for connecting the ends of the foil to a voltage source.

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