RU2262162C1 - Method for checking tightness of metal-hydrogen battery - Google Patents

Abstract

FIELD: electrical engineering; servicing metal-hydrogen batteries including their checking for tightness.

SUBSTANCE: proposed method for checking tightness of metal-hydrogen battery includes measurement of pressure within battery case and temperature on its surface; comparison of measured values with maximum permissible ones; estimation of its tightness by making sure that measured parameters are kept within permissible range; measurement of gas space volume; evaluation of battery case expansion ratio for measured temperatures and pressure; determination of battery degree of charge within which only hydrogen is liberated during charging period; battery charging within mentioned range at the same time measuring rated charge current and degree of battery charge within hydrogen liberation range; evaluation of mean volumetric temperature of hydrogen in battery case; evaluation of hydrogen flow due to electrochemical reaction Q_ech within battery by measured charge current and mentioned mean volumetric temperatures of hydrogen; evaluation of hydrogen barometric flow Q_bar within battery by measured values of battery gas space volume, temperatures on its case, and pressure within case, evaluated expansion ratios of battery case for mentioned measured temperatures and pressures; battery tightness is found adequate if condition Q_ech - Q_bar ≤ Q_p, is satisfied, where Q_p is permissible value of battery leakage. In this way in-service checking of battery tightness is made by hydrogen leakage within permissible level of battery sensitivity.

EFFECT: enhanced reliability of in-service hydrogen leakage evaluation within permissible level of battery sensitivity.

1 cl, 5 dwg

Description

The invention relates to electrical engineering and can be used in the operation of a metal-hydrogen battery (MVA) to check for leaks.

A known method of monitoring the tightness of pneumohydrosystems [1], used in space technology and adopted as an analogue.

The essence of the method lies in the fact that the spacecraft (SC) is placed in a vacuum chamber connected to a leak detector, while the volume of the vacuum chamber communicates with the internal cavity of the compartment. The chamber and compartment are evacuated by means of pumping to the maximum residual pressure in the vacuum chamber. Then a calibrated flow of control gas of a given value is fed there. The difference in the concentration of the control gas in the vacuum chamber from the calibrated flow is measured. After measurements, the supply of a calibrated flow of control gas to the vacuum chamber is stopped. The pneumohydrosystem is charged with control gas. The change in the concentration of the control gas in the vacuum chamber from the micro-leaks in the units and highways of the pneumatic system is measured, and the tightness of the pneumatic system is judged by the ratio of the measured changes in the concentration of the control gas.

The indicated control method can be used for MVA only if it is inoperative, and only to control the tightness of the body (vessel) that is not under working pressure. In this case, only hydrogen can be used as a control gas, which for such tests in vacuum technology, due to its explosiveness, is not used. The use of other gases for such purposes, including neutral ones (for example, helium), cannot further guarantee the regular operation of the MVA electrochemical battery (ECB), since the remnants of the control gas can further interfere with the main electrochemical processes occurring in the battery.

It is known that for control of MVA during operation, the most used are the parameters of pressure, temperature and voltage [2, p. 266]. The specified parameters are also used to control the tightness of the MBA. A method of monitoring the tightness of a metal-hydrogen battery, including measuring the pressure inside its case and the temperature on the battery case, comparing the measured values with the maximum allowable and determining the tightness by finding the measured parameters in the acceptable range, is taken as a prototype [2, p.265-266].

Acceptable gradients of growth or pressure drop inside the battery housing can be judged on its tightness. In case of leaks, the specified tolerances are exceeded, up to the mechanical rupture of the vessel. However, this method of control is rather rough, and the situation associated with rupture of the vessel is prevented by the choice of the safety factor of the material in the manufacture of cases [2, p. 266].

The most probable cause of the MBA leak is the leakage of hydrogen from the battery both through its body and through the assembly sites of additional structural elements that make up the battery. Monitoring of hydrogen leakage can be carried out by the voltage of the battery and by the temperature on its housing [2, p. 265]. The fact of a partial loss of hydrogen is established by the voltage drop during the charge. On a nickel-hydrogen battery, for example, the voltage drop is from 1.4 ... 1.6 V to 0.5 ... 0.6 V.

In addition, the MBA is very hot, since almost all the power supplied to it goes into heat.

The main disadvantages of the prototype method are as follows. It is practically impossible to control the MVA tightness by pressure drop inside the housing for micro-leaks, this is due to the fact that the process of converting chemical energy directly to electric energy in the accumulator is accompanied by pressure changes associated not only with the ongoing thermodynamic processes, but also with electrochemical processes. Therefore, in addition to the pressures and temperatures in the closed volume of the battery, it is necessary to take into account to control the flow of emitted gases (oxygen and hydrogen) and the magnitude of the battery currents. In many respects, the gas evolution process also depends on the design of the battery itself, the construction of its ECB, the scheme for removing excess heat from the battery, and other features.

The parametric manifold characterizing the operation of the MBA introduces an error in the process of monitoring its tightness by pressure, while the magnitude of this error does not allow to bring the sensitivity of the method to control the values of small leaks (~ 0.1 μm Hg · l / s).

Temperature tightness control on the battery case also has a significant drawback, since it is not the process of leakage from the battery that is controlled, but the consequences of this leakage. Thus, it is not possible to take into account the negative process in the operational strategy of the MBA and it is necessary to react only to the consequences of this leak.

In addition, for MVA with a common gas collector [3] and with elements connected in series, it is not possible to control the temperature and voltage on an individual element, since the voltage on the ECB, measured as the sum of the voltages of each element, can generally be estimated differently . On the one hand, when it falls, one of the elements may fail, on the other, a voltage drop on each of the elements associated with a hydrogen leak from the battery case. And the temperature control system (STR) of ECB, for example, with the help of heat pipes closed to radiators-heat exchangers (RTO) [see (3)], can provide the necessary heat discharge from MVA.

Thus, as in the case of pressure, leakage can be judged with a significant degradation of the battery as a whole, when the load on the CTP will not increase in proportion to the heat capacity of the battery associated with its regular operation.

The challenge facing the proposed method is to ensure ongoing monitoring of the tightness of the metal-hydrogen battery during its operation for hydrogen leakage within the sensitivity range at a level acceptable for the battery.

The technical result is achieved by the fact that in a method for monitoring the tightness of a metal-hydrogen battery, which includes measuring pressures inside the case and temperatures on the body of the metal-hydrogen battery, comparing the measured values with the maximum allowable and determining the tightness by finding the measured parameters in the acceptable range, measure the volume of the gas cavity metal-hydrogen battery, determine the expansion coefficients of the housing of the metal-hydrogen battery for the indicated measured values of the pace atures and pressures, determine the range of values of the degree of its charge, within which only hydrogen is released when the metal-hydrogen battery is charged, the metal-hydrogen battery is charged within the specified range, while the rated charging current is measured, simultaneously, in the same range of values the degree of charge of the metal-hydrogen battery, within which only hydrogen is released when it is charged, the volume-average values of the temperature of hydrogen in metal-water are determined own battery, the measured values of the charging current and determining said values of the volume average hydrogen temperature is determined hydrogen flow from an electrochemical reaction in the battery (Q _eh) from measured values of the volume of the gas cavity metal-hydrogen battery, temperature of a housing and pressures inside the cabinet, certain values expansion coefficients of the metal-hydrogen accumulator case for the indicated measured values of temperatures and pressures, determine the barometric flow of hydrogen in ac umulyatore (Q _bar) and sealing metal-hydrogen battery is judged by the execution conditions

Q _eh -Q _bar ≤Q _add ,

Q _add - allowable leakage value of a metal-hydrogen battery.

To describe the proposed method introduced figure 1 ... figure 5, which presents:

figure 1 - device Nickel-hydrogen storage battery with a common gas collector;

figure 2 - placement of current leads on the housing of a Nickel-hydrogen battery with a common gas collector;

figure 3 - placement of pressure sensors on the housing of a Nickel-hydrogen battery with a common gas manifold;

figure 4 - graphs of the measured telemetric parameters of the Nickel-hydrogen battery during the charging cycle;

figure 5 - dynamic errors of the measured and calculated parameters of the Nickel-hydrogen storage battery.

To explain the essence of the proposed technical solution, let us consider, as an example, a nickel-hydrogen storage battery (NVAB) designed to directly convert electrical energy into chemical energy of the reaction of interaction between nickel hydroxide and hydrogen, storing it in this form for the necessary time and reverse direct conversion of the chemical energy of the reactants into electrical energy.

The NVAB device is presented in figures 1-3, where the conventions are introduced:

1 - ECB;

2, 3 - parts of the power housing: the first and second hemispheres, respectively;

4 - pressure sensors (three in total);

5 - current leads with pressure sockets (only two);

6 - nozzle for refueling with hydrogen;

7 - seat installation of heat pipes;

8 - a nut;

9 - a central hairpin;

10 - adapter of the central stud;

11 - current lead;

12 - power terminals of current leads;

13 is a cylindrical insert.

ECB1, located in a welded power case, consisting of two parts 2 and 3 of a spherical shape and a cylindrical insert 13, performs the functions of an energy converter.

When assembled, the casing is a high-pressure cylinder, which is filled with hydrogen. Three pressure sensors 4 are installed on the cylinder, providing pressure measurement inside the NVAB housing and controlling the operation of ECB1, two current leads with pressure connectors 5, which allow supplying and removing electric energy from ECB1, and a nozzle 6 for testing and filling the NVAB with hydrogen.

In addition, as a rule, temperatures are measured on the NVAB housing by installing (gluing) from three to six temperature sensors in different places on the housing surface. The same sensors are installed on heat pipes [see (3)].

In the axial part of the NVAB, there are two cylindrical seats 7 for installing the evaporative part of two heat [see (3)], which provide heat transfer from ECB1 to heat pipes. To increase heat transfer, the gap between the design of ECB1 and the seats for installing heat pipes 7 is filled with heat-conducting paste.

The ECB1 is attached to the first hemisphere 2 using a nut 8, followed by welding of the joints between the central pin 9 and the adapter of the central pin of the housing 10.

The second fulcrum of the ECB1 in the second hemisphere 3 is sliding, providing movement of the housing along the stud when pressure and temperature inside the housing change. After installing the ECB in the hemisphere 2, the corresponding power terminals 12 of the current leads 11 are connected to the buses "+" and "-" ECB.

NVAB is made with a common gas collector, which allows to provide high stored energy per unit mass (not less than 50 W · h / kg), and volume (not less than 100 W · h / l), high reliability and safety.

ECB1 contains electrical groups consisting of a negative hydrogen gas diffusion electrode made in the form of a metal gilded nickel mesh with a catalyst embedded in it (platinum with fluoroplastic), a positive oxide-nickel electrode (ONE), which is a highly porous nickel structure filled with nickel hydroxide .

The thickness of the positive electrode (mass) determines the total stored energy of the battery and electron carrier.

The electrolyte is an aqueous solution of alkali (KOH), which is contained in a special porous matrix.

When charged, hydrogen is restored on the hydrogen electrode and fills the total volume of the battery, while the pressure in the tank (the barodynamic dependence of NAB) increases approximately in proportion to the charged battery capacity. Each temperature value measured on the NVAB housing has its own schedule for the permissible pressure increase inside the battery case at rated charging current (see [2], Fig. XI.5, p. 259).

Comparing the measured values with the maximum permissible values, the tightness of the housing can be determined by finding the measured parameters in the acceptable range.

During the discharge, hydrogen is ionized and the electrochemical formation of Ni (OH) ₂ occurs, while the hydrogen pressure decreases approximately in proportion to the consumed capacity of the battery. The average potential of one element during a discharge is ~ 1.25 ... 1.3 V.

For example, we take ECB1 in the form of a package [see (3)], which consists of eighteen battery cells connected in series to each other, combining electrical groups.

We will also take to control the tightness of the NVAB, which is in the charging cycle. The indicated cycle is the most dangerous in case of the shell’s internal gas pressure, the growth of which can amount to tens of atmospheres during the charge up to a maximum value of ~ 60 kgf / cm ² .

Let us write down a system of equations describing the calculation of the leakage rate of an NLAB.

1. Electrochemical consumption of hydrogen (generalized Faraday law in differential form - [4], p. 388).

where μ _H2 = 2 is the kilomole mass of hydrogen, [kg / kmol];

n = 18 - the number of cells connected in series in NVAB, [-];

Z _H2 = 2 is the valence of hydrogen, [-];

F = 9.6485 · 10 ⁷ is the Faraday number, [A · s / kmol];

I (τ) is the measured value of the current in the charge cycle of the NVAB, [A];

η = η (C / C _NOM; T _EHB; I, n _C) - the distance value efficiency current in charge mode (a complex empirical function of many variables), [-];

С / С _НОМ - calculated degree of charge of NVAB, [-];

T _ECB - calculated _volumetric average temperature of the electrochemical battery (ECB), [C];

n _C - the number of charge-discharge cycles at the current time of the resource operation of the NVAB, [-].

2. Barometric hydrogen flow rate (Mendeleev-Clapeyron equation in differential form - [4], p. 151).

where V _Н2 (Р, Т _К ) - calculated volume occupied by gaseous hydrogen in NVAB (technical measurement system), [l];

R _O = 8314 is the universal gas constant, [J / (kmol · K)];

P (τ) is the measured pressure of hydrogen in NVAB (technical measurement system), [kgf / cm ² ];

Т _Н2 (τ) - calculated volumetric average temperature of hydrogen in NVAB, [С];

T _K (τ) - the measured temperature of the housing NVAB, [C];

k _P = 9.81 · 10 ⁴ - conversion factor for measuring pressure in the SI system, [(n / m ² ) (kgf / cm ² )];

k _V = 10 ^-3 - conversion factor for measuring volume in the SI system, [m ³ / l].

3. Hydrogen consumption (leak) through the gas-permeable shell of the NVAB housing and sealing elements of the structure (expense balance).

4. The calculated value of the average (integral) temperature over the internal volume of the NVAB ([5], p. 31) in the general form

In private form for cylindrical layers of ECB and gas cavity we have:

where T (r) is the calculated distribution of the temperature along the radius in the cylindrical layers of NVAB;

r ₀ , r ₁ , r ₂ are the radii of the inner surface of the ECB, the outer surface of the ECB and the inner surface of the NVAB housing, respectively.

5. The measurement of the volume of the gas cavity of the battery is carried out taking into account the "breathing" of the spherical housing of the NVAB from temperature and pressure factors.

where V ₀ is the measured volume of the gas cavity of the NVAB during acceptance tests with a temperature T ₀ and pressure P _{0 of} the environment (the value of the volume is entered in the form), [l];

ΔV _T is the volume increment from the temperature factor, [l];

ΔV _p is the volume increment from the pressure factor, [l];

β _t - temperature coefficient of linear expansion of the housing material, [1 / C];

the calculated coefficient of expansion of the body from the pressure factor, [kgf / cm ² ] ^-1 ;

Δt = (T _K -T ₀ ) - change in temperature of the housing, [C];

ΔP = (P-P ₀ ) is the change in hydrogen pressure, [kgf / cm ² ];

T ₀ , P ₀ - measured environmental parameters when determining the volume V ₀ for the gas cavity NVAB (parameter values are entered in the form);

P _K - excess test pressure to determine the coefficient β _P at T _K = T ₀ = Const;

ΔL _K - measured linear elongation of the circumference of the body under the influence of the test pressure factor Pk, [mm];

D ₀ - the measured diameter of the housing NVAB with parameters T ₀ and P ₀ , [mm].

6. Leakage rate (leak).

Equation {3} describes the material balance of gas consumption, expressed in units of mass. In a vacuum technique, a calculated gas flow is used to measure a leak, expressed in arbitrary units of the flow determined by an expression that is valid at a constant temperature (calculated gas leak flow - [6], p. 156):

Where

- the calculated average value of the temperature of hydrogen in NVAB during the implementation of the control method, [K];

τ ₁ and τ ₂ - the measured time of the beginning and end of the method of monitoring leaks, respectively, [s];

Δτ = (τ ₂ -τ ₁ ) is the duration of the method of tightness control, [s];

k _P = 7.5 · 10 ³ - conversion factor for measuring gas flows in the technical measurement system, [(μm Hg · l / s) / (W)].

Consider in detail the application of the proposed method for monitoring the tightness of a metal-hydrogen (nickel-hydrogen) battery.

Before using the battery, measure the volume of the gas cavity V ₀ .

For this, the technological connection 6 is used (see figure 1). Through it, for example, the battery is charged with a calibrated mass of hydrogen. Next, the volume of the gas cavity of the battery is measured by the known mass of hydrogen, the measured temperature on the housing and the pressure inside the housing.

We determine the expansion coefficients β _T and β _p (see {6}), while taking into account the operating range of temperatures and pressures of the battery obtained during its operation. We determine the range of values of the degree of charge of the battery (C / C _nom ), within which only hydrogen is released when the battery is charged. To do this, we use the known dependences on the pressure change in the function of the relative charge capacity (degree of charge) at various temperatures, (see [2], p. 259).

From the indicated dependences, we determine the areas only for hydrogen evolution, characterized by a constant gradient of pressure change. For example, C-band / S _SG of from 0.1 to 0.5 (see [2]., Ris.XI.5, str.259) hydrogen is released at a temperature of from 0 ° to 40 ° C.

For the indicated region of the degree of charge, an almost constant value η≈1 is guaranteed to be realized. This greatly simplifies the determination of Q _SEC by the measured charging current when the battery is charged within the specified range. In addition, the choice of the region of hydrogen evolution leads to an increase in the accuracy of the control method, since this region is characterized by a minimum intrinsic heat release of the NAB and, as a result, stability and uniformity of temperature distribution over the battery design, which allows the accuracy of replacing the calculated value of the average volumetric temperature of hydrogen T _H2 the measured value of the temperature of the housing T _To .

For the presented domain of definition, taking into account the assumptions made, after the transformation of the above system of equations {1} ... {8}, the final expression for the calculated current leak rate is:

Where

a certain value of the flow of hydrogen in the battery from an electrochemical reaction;

a certain value of the barometric flow of hydrogen in the battery.

Determine the average value of the temperature of hydrogen during the implementation of the method:

where T _K (τ) is the measured temperature of the housing;

τ ₁ and τ ₂ - the measured time of the beginning and end of the method of monitoring leaks, respectively, [h].

We determine the average value of the calculated pressure gradient (taking into account the "respiration" of the case from temperature and pressure factors) during the implementation of the method for Q _BAR :

Where:

P (τ) is the measured hydrogen pressure;

- the analytical dependence of the relative volume of hydrogen on the current parameters of the hydrogen pressure and the temperature of the housing;

Δt = Т _К (τ) -Т ₀ - current temperature difference, [С];

ΔP = P (τ) -P ₀ is the current pressure difference, [kgf / cm ² ];

τ ₁ and τ ₂ - the measured time of the beginning and end of the method of monitoring leaks, respectively, [h].

Determine the average measured value of the charging current during the implementation of the method for Q _SEC :

where I _i - the current measured values of the charging current in the field of implementation of the method.

Comparison of current and permissible leak rates:

If condition {18} is fulfilled, one can judge the tightness of the MBA.

Figure 4 shows the daily graphs of the measured telemetric (TM) parameters of the NVAB installed on the spacecraft "Yamal-100" during the charging cycle in the normal operation of the battery.

In addition to the previously considered notations, the following are again introduced:

_{TT TT} - the temperature of the heat pipes in the installation area on the PTO, [C],

W is the battery charge level [Wh].

Based on the above assumptions, the area of practical implementation of the method was selected in the range W = (0.1 ... 0.3) W _NOM , in the interval Δτ = 1.5 hours. As can be seen from the fragments of the graphs belonging to the region, for the calculated dependence {1} in accordance with [2], p. 259, the value η≈1 is guaranteed to be realized.

At nominal current measured values of the charging current I ≈ 11 A, a linear increase in pressure R is observed. The temperatures on the heat pipes Т _ТТ and the housing of НВАБ Т _К have approximately constant values (Т _ТТ ≈6 ° С and Т _К ≈9 ° С), which in the expression {14} allows us to take as the volumetric average temperature of hydrogen, the measured value of the temperature of the NVAB (T _K ) body. The temperature difference between T _K and T _TT by 3 degrees characterizes the heat removal from the ECB of the battery, carried out through the RTO [see (3)]. In this case, the current values of the battery charge levels W are calculated using the measured values of the temperature on the housing T _K and the pressure inside the housing P according to the expression:

where K is the coefficient of proportionality;

P ₀ - pressure in NVAB at the end of a full discharge, [kgf / cm ² ].

Thus, all the variables obtained from the measurement results included in the expression {9} for calculating Q _{LEAKS are} obtained. The remaining quantities included in the indicated expression are either constant, see {9, ..., 14}, or depending on the indicated variables.

To improve the accuracy in determining the actual error rate, in the practical implementation of the method, it is necessary to smooth out the "dynamic noise level" of the measured parameters.

Figure 5 shows the dynamic error ("noise level") of the measured and calculated parameters for the expression {9}, taking into account the substitution {10}, {11}. Their approximation and the calculated value of Q _leak , obtained after substitution of the following calculated values in {9, ..., 11} are also shown there:

V ₀ = 16 [l]; I _MOD = 10.99457 [A]; T _cf = 8.977064 [C];

(PQ) Δτ = 5.5144 [(kgf / cm ² ) / 4], m ₁ , m ₂ , see {9}, {10},

in this case, the processed measured current value of the charging current I, taking into account the approximation reliability value (R ² ), is accepted as I _ISM .

Taking into account Q _add = 0.08 [μm Hg · l / s] and the obtained Q _LEAK ≈0.01 [μm Hg · l / s], by fulfilling the condition {18} it is possible to judge the tightness of the controlled NVAB. In this case, the smoothing of values was carried out using the least squares method. Figure 5 shows the values of the approximation confidence (R ² ) of the measured and calculated values used in the calculated expression {9}.

The necessary accuracy and certification of the method for monitoring the tightness of NVAB during ground training and regular operation is achieved by the following measures:

- completing the NVAB with accurate measuring equipment, taking into account the secondary conversion of the output analog signal in the on-board control algorithm, including for the following parameters: I, P, T, Δτ;

- conducting individual calibration tests for each NVAB regarding the definition of technical characteristics with their entry in the form, including for the following parameters: V ₀ , T ₀ , P ₀ , β _p , β _t , η;

- development of an algorithm for determining the design parameters in terms of the temperature distribution T (r) along the radius in the cylindrical layers of the NVAB according to the measured input parameters;

- mathematical processing (approximation and smoothing) of the measured parameters I, P, T _K in order to eliminate the dynamic error from electromagnetic interference in the secondary signal conversion system - smoothing the "noise level".

The performance of the MBA largely depends on the integrity and integrity of the design of its housing. Destruction of the housing design leads to a complete loss of performance. Possible irreversible leaks of the working fluid with an increased leak rate lead to accelerated degradation of its technical characteristics during normal (resource) operation. Moreover, the rate of degradation directly depends on the magnitude of these leaks. In the event of an MBA leak, the strategy for its further operation should accordingly change with the inevitable decrease in the technical characteristics of the battery in comparison with the standards of technical conditions for operation.

During the design and development of the MBA used on the spacecraft, the necessary leakage standards are established, which make it possible to provide technical characteristics for a given battery life. In ground testing and acceptance tests, various regulatory methods are used to determine and confirm the design tightness standard using special expensive ground equipment and fittings (vacuum stands, reference pressure gauges, mass spectrometer, etc.). However, the control methods used in this case are not suitable for the regular operation of the spacecraft in space flight conditions.

During long-term regular operation of the MBA as part of the spacecraft, it becomes necessary to verify the actual leak rate using simple means of measuring the parameters of the battery included in its composition. Such a check is necessary for the correct assessment of the technical condition of the MBA and confirmation of its electrical resource characteristics, subject to the condition of permissible tightness of the ampouled volume with a gaseous working fluid (hydrogen).

The known method is a prototype of the control of the actual leakage rate of pressure drop is not acceptable for the regular operation of the MVA in the conditions of variable temperature control and various operating modes of the battery.

The proposed method allows for space flight to carry out current (operational) control of the tightness of the MBA sensitivity is comparable with the specified methods of ground control.

The availability of leakage information allows you to build an appropriate battery management strategy. So if there is a hydrogen leak above the permissible leakage value, to extend the battery life it is necessary to increase the duration of its storage in the discharged state and charge it in cases of the predicted demand for electricity from secondary power sources. For example, before passing through the “shadow” sections of the spacecraft’s orbit and before the end of the indicated sections, the battery is charged, then storage is in a discharged state. Other options are also possible in the MBA operation strategy.

If backup batteries are available, it is necessary to switch to them, using the leaky battery resource to the end, and also review the spacecraft’s energy balance in the direction of introducing energy saving modes, transferring electricity to other forms of energy - thermal, mechanical, compressed gas energy, in flight areas with an excess of generated energy on board the apparatus and thereby reducing the cost of battery power in critical areas of its operation (reduce power consumption by heating the const uktsii, gases and al.).

These measures allow you to extend the life of the device.

Thus, the presented method actually solves the problem of extending the spacecraft life in the event of a gas (hydrogen) leak from MVA devices.

Literature

1. Lipnyak L.V., Panov N.G., Scherbakov E.V. A method of monitoring the tightness of pneumohydrosystems. RF patent 2086941.

2. Center B.I., Lyzlov N.Yu. Metal-hydrogen electrochemical systems. Leningrad, "Chemistry", Leningrad branch. 1989.

3. Chelyaev V.F., Nikitin V.A., Matrenin V.I., Tsedilkin A.P. Battery with metal-gas elements. RF patent 2118873.

4. B.M. Yavorsky, A.A. Detlaf. Handbook of Physics. Publishing House "Science", Main Edition of Physics and Mathematics, Moscow. 1979.

5. A.V. Lykov. Theory of thermal conductivity. Higher School Publishing House, Moscow. 1967.

6. L.N. Rozanov. Vacuum technology. Higher School Publishing House, Moscow. 1982.

Claims (1)

A method of monitoring the tightness of a metal-hydrogen battery, including measuring pressures inside the case and temperatures on the body of the metal-hydrogen battery, comparing the measured values with the maximum allowable and determining the tightness by finding the measured parameters in the acceptable range, characterized in that the volume of the gas cavity of the metal-hydrogen is measured the battery, determine the expansion coefficients of the housing of the metal-hydrogen battery for the specified measured values of temperature and pressure, determined they determine the range of values of the degree of its charge, within which only hydrogen is released when the metal-hydrogen battery is charged, produce a charge of the metal-hydrogen battery within the specified range, while measuring the nominal charging current at the same time, in the same range of values of the degree of charge of the metal-hydrogen accumulator, within which only hydrogen is released during its charge, determine the volumetric average temperature of hydrogen in a metal-hydrogen battery, Measurements of the values of charging current and determining said values of the volume average hydrogen temperature is determined hydrogen flow from an electrochemical reaction in the battery (Q _eh) from measured values of the volume of the gas cavity metal-hydrogen battery, temperature of a housing and pressures inside the cabinet, certain values of the coefficients of expansion of the metal housing -vodorodnogo battery to said measured values of temperature and pressure determine the barometric hydrogen stream in the accumulator (Q _bar) and Germ ticity metal-hydrogen battery is judged to fulfill the conditions Q _eh- Q _bar ≤Q _add , Q _add - allowable leakage value of a metal-hydrogen battery.

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