Current-based thermal battery electrolyte water content equipment level detection method and system

Abstract

The application discloses a current-based thermal battery electrolyte water content equipment level detection method and system, and solves the technical problem that thermal battery electrolyte material water content cannot be nondestructively detected at the equipment system level. The method comprises the following steps: the application is applied to the state of an equipment system containing a thermal battery; the positive and negative electrodes of an ammeter are connected to the positive and negative electrodes of the thermal battery in the system, respectively, and the short-circuit output current of the thermal battery connected to the equipment system and in an inactivated state is measured by the ammeter; and the water content of the thermal battery electrolyte material is calculated by using a nonlinear electrolyte material water content calculation method according to the measured short-circuit output current. The application can obtain the water content of the thermal battery electrolyte material connected to the equipment system in real time based on the short-circuit output current of the thermal battery in the inactivated state, has the advantages of high speed, high measurement accuracy, low cost, no damage to the product and on-line nondestructive detection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of thermal battery detection, and particularly relates to a method and system for detecting the water content of the electrolyte of a thermal battery based on current. BACKGROUND

[0002] A thermal battery is a disposable reserve battery widely used in various types of equipment, which is connected in series and parallel with electronic components, mechanical components, sensor components and other modules to form an equipment system and provide power for the equipment system, and has the characteristics of long storage life, high reliability, high safety, high specific energy and high specific power. A thermal battery is generally composed of a plurality of single battery pieces connected in series, each single battery piece is composed of a positive electrode, an electrolyte and a negative electrode, and the electrolyte is a molten salt that is almost non-conductive at room temperature. Since the molten salt electrolyte is easily hygroscopic, it often contains a certain amount of water. During long-term storage or operation of the thermal battery, the water released from the molten salt reacts with the positive and negative electrode materials, resulting in a decrease in battery performance. Therefore, the water content in the electrolyte material is one of the key factors for reflecting the health status of the thermal battery, and the change in the trace water content in the electrolyte of the thermal battery must be strictly controlled and monitored.

[0003] Currently, the commonly used methods for detecting the water content of the molten salt material of the thermal battery include Karl Fischer method and thermogravimetric method, but these methods are destructive tests. When testing the water content in the electrolyte material of the thermal battery, the thermal battery must be destroyed to obtain the electrolyte material, and the sample preparation and measurement process is easily affected by the environmental humidity and needs to be operated in a dry environment, which is very complex.

[0004] In addition, Meizhou Liangneng New Energy Technology Co., Ltd. reported a method for detecting the water content of the electrode plate of a battery, which measures the resistance of the battery electrode plate to detect the water content of the battery electrode material. However, this method cannot be applied to the detection of the water content of the electrolyte material of the thermal battery. Because the resistance measurement requires applying a voltage or current excitation signal between the positive and negative electrodes of the battery, however, in the equipment system, the positive and negative electrodes of the thermal battery are connected in series or parallel with other devices in the system. On the one hand, the applied voltage and current excitation signal may damage these devices, and on the other hand, these devices will form a current bypass, making it impossible to accurately measure the resistance of the thermal battery connected in the equipment system. SUMMARY

[0005] The technical problem to be solved by the present application is that the water content in the electrolyte material of the thermal battery connected in the equipment system cannot be accurately and non-destructively detected.

[0006] The application aims to provide a current-based thermal battery electrolyte water content equipment-level detection method and system, and is applied to the state of an equipment system containing a thermal battery; the positive and negative electrodes of an ammeter are connected with the positive and negative electrodes of the thermal battery in the equipment system respectively, the short-circuit output current I0 of the thermal battery in an inactivated state at an ambient temperature T0 is measured, the water content Y in the electrolyte material is calculated according to the short-circuit output current I0 of the thermal battery in the inactivated state and by using a pre-determined nonlinear electrolyte material water content calculation method. The application can obtain the water content in the electrolyte material of the thermal battery connected to the system in real time based on the short-circuit output current of the thermal battery in the inactivated state, has fast speed, accurate measurement, low cost, no damage to the product, and can be detected on line and non-destructively.

[0007] The application is realized by the following technical solutions:

[0008] In a first aspect, the application provides a current-based thermal battery electrolyte water content equipment-level detection method, which comprises:

[0009] The short-circuit output current I0 of the thermal battery in the equipment system in an inactivated state is measured by using an ammeter.

[0010] The electrolyte material water content of the thermal battery in the system is calculated by using a nonlinear electrolyte material water content calculation method according to the short-circuit output current I0.

[0011] Further, the short-circuit output current I0 of the thermal battery in the equipment system in an inactivated state is measured by using an ammeter, specifically:

[0012] The positive and negative electrodes of the ammeter are connected with the positive and negative electrodes of the thermal battery in the equipment system respectively, the short-circuit output current I0 of the thermal battery in an inactivated state at an ambient temperature T0 is measured, wherein 273K <= T0 <= 373K, K is the absolute temperature unit of Kelvin.

[0013] Further, the calculation formula of the nonlinear electrolyte material water content calculation method is:

[0014] Y = a x {I0 x exp[-c x (1 / T1-1 / T0)] x h0 / S0} b

[0015] Wherein Y is the water content of the electrolyte material of the thermal battery in the system, I0 is the short-circuit output current of the thermal battery in the equipment system in an inactivated state, a is a material process factor, b is a power index, c is a temperature conversion factor, S0 is the area of a single battery piece, h0 is the thickness of the electrolyte material layer in the single battery piece, T0 is the test ambient temperature, T1 is the pre-test ambient temperature, and exp is the exponential function with the natural constant e as the base.

[0016] Further, the material process factor, the power index and the temperature conversion factor are obtained by the following method:

[0017] Step A, dry or absorb moisture of n parts of electrolyte materials with the same mass, so that the water content of the electrolyte materials is Y1, Y2, …, Yj, …, Yn respectively, 0<Y1<Y2<…<Yj<…<Yn<1; wherein j is an integer greater than 1 and less than n;

[0018] Step B, press the above n parts of electrolyte materials and positive electrode materials, negative electrode materials into n single battery pieces with an area of S1 and an electrolyte layer thickness of h1 respectively;

[0019] Step C, measure the short-circuit output current of the n single battery pieces in step B at ambient temperature T1, which are I11, I12, …, I1j, …, I1n respectively, wherein 273K<=T1<=373K;

[0020] Step D, take I11, I12, …, I1j, …, I1n as independent variable I1, and Y1, Y2, …, Yj, …, Yn as dependent variable Y, and use Y=a×[I1×h1 / S1] b to fit and obtain coefficients a and b;

[0021] Step E, measure the short-circuit output current I21, I22, …, I2k, …, I2m of any single battery piece in step B at ambient temperature T21, T22, …, T2k, …, T2m, wherein 273K<=T21<T22<…<T2k<…<T2m<=373K, m is an integer greater than 2, and k is an integer greater than 0 and less than m;

[0022] Step F, take T21, T22, …, T2k, …, T2m as independent variable T2, and I21, I22, …, I2k, …, I2m as dependent variable I2, and use I2=d×exp(-c / T2) to fit and obtain coefficients d and c, wherein d is the pre-exponential factor of temperature test, and c is the temperature conversion factor.

[0023] Further, the equipment system includes thermal batteries, electronic components, mechanical components and sensor components, and the thermal batteries and the electronic components, mechanical components and sensor components are connected in series and in parallel.

[0024] Further, the electrolyte material of the thermal battery in the equipment system is a mixture of molten salt material and adsorption material in any proportion.

[0025] Further, the molten salt electrolyte is one of LiCl, KCl, LiF, LiBr, KBr, LiI, NaBr, LiNO3, KNO3, RbNO3, NaNO3, Li2CO3, Li2SO4, Li3PO4 or a solid solution or mixture formed by multiple materials.

[0026] Further, the adsorbing material is MgO, Al2O3, Li7La3Zr2O 12 , SiO2, BN or the like.

[0027] Further, the positive material in step B is FeS2, Fe x Co 1-x S2, CoS2, V2O5, NiCl2 or the like, and the negative material in step B is LiB, LiSi, LiAl, LiIn, LiFe or the like.

[0028] In a second aspect, the application further provides a current-based thermal battery electrolyte water content equipment-level detection system, which comprises:

[0029] a measuring unit for measuring the short-circuit output current I0 of the thermal battery in the equipment system in an inactivated state by using an ammeter, comprising: connecting the positive electrode and the negative electrode of the ammeter to the positive electrode and the negative electrode of the thermal battery in the equipment system respectively, and measuring the short-circuit output current I0 of the thermal battery in the inactivated state at an environmental temperature T0; wherein 273K <= T0 <= 373K;

[0030] a calculating unit for calculating the electrolyte material water content of the thermal battery at the system level by using a non-linear electrolyte material water content calculation method according to the short-circuit output current I0; the calculation formula of the non-linear electrolyte material water content calculation method is:

[0031] Y = a x {I0 x exp[-c x (1 / T1-1 / T0)] x h0 / S0} b

[0032] wherein Y is the water content of the electrolyte material of the thermal battery at the system level, I0 is the short-circuit output current of the thermal battery in the equipment system in the inactivated state, a is a material process factor, b is a power index, c is a temperature conversion factor, S0 is the area of the monomer battery sheet, h0 is the thickness of the electrolyte material layer in the monomer battery sheet, T0 is the test environmental temperature, T1 is the pre-test environmental temperature, and exp is an exponential function with the natural constant e as the base.

[0033] Compared with the prior art, the application has the following advantages and beneficial effects:

[0034] The application is based on the current-based thermal battery electrolyte water content equipment level detection method and system, and is applied to the equipment system state containing the thermal battery; the positive and negative electrodes of the ammeter are connected with the positive and negative electrodes of the thermal battery in the equipment system respectively, the short-circuit output current I0 of the thermal battery in the unactivated state under the environmental temperature T0 is measured; the water content Y in the electrolyte material is calculated by using the nonlinear electrolyte material water content calculation method according to the short-circuit output current I0 of the thermal battery in the unactivated state. The water content in the electrolyte material of the thermal battery can be obtained in real time based on the short-circuit output current of the thermal battery in the unactivated state which has been connected to the equipment system, the speed is fast, the measurement is accurate, the cost is low, the product is not damaged, and the on-line nondestructive detection can be realized. BRIEF DESCRIPTION OF DRAWINGS

[0035] The accompanying drawings, which are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this application, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings:

[0036] Figure 1 The application is based on the current-based thermal battery electrolyte water content equipment level detection method flow chart;

[0037] Figure 2 The application is based on the current-based thermal battery electrolyte water content equipment level detection method flow chart;

[0038] Figure 3 The application is based on the current-based thermal battery electrolyte water content equipment level detection method flow chart;

[0039] Figure 4 The application is based on the current-based thermal battery electrolyte water content equipment level detection method flow chart;

[0040] Figure 5 The application is based on the current-based thermal battery electrolyte water content equipment level detection system structure block diagram. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical scheme and advantages of the application clearer, further detailed description of the application will be given below in combination with the embodiments and drawings, the illustrative embodiments of the application and the description thereof are only used to explain the application, and do not limit the application.

[0042] The application designs a thermal battery electrolyte moisture content equipment level detection method based on current, which can obtain the moisture content in the thermal battery electrolyte material connected to the equipment system in real time based on the short-circuit output current of the thermal battery in the unactivated state, is fast, accurate, low in cost, non-destructive and can be detected on line.

[0043] The basic principle of the application is that the thermal battery is connected in series by monomer battery pieces, heating pieces and current collectors, and an interface electric field is formed at the interface between the electrolyte and the positive electrode material and the interface between the electrolyte and the negative electrode material due to the difference in the electrochemical potential of lithium ions in the electrolyte and the electrode material in the unactivated state of the thermal battery, so that a potential difference exists between the positive electrode and the negative electrode in the unactivated state of the thermal battery, and the thermal battery outputs a weak current when the external circuit is connected. When the thermal battery is placed in the equipment system, the thermal battery and other devices in the equipment system are connected in series, and the weak current flows through the other devices. When the positive and negative poles of the ammeter are connected to the positive and negative poles of the thermal battery in the equipment system, respectively, the other devices connected in series with the thermal battery are bypassed, and the current flows through the ammeter due to the near 0Ω resistance of the ammeter. Since the heating piece, current collector, positive electrode and negative electrode in the thermal battery are all conductors with very small resistance, they have little effect on the short-circuit output current of the thermal battery. The main factors affecting the short-circuit output current are the carrier transport capacity of the electrolyte material, the thickness and area of the electrolyte material, and the two factors of the carrier transport capacity and the trace moisture content in the electrolyte material are related to the temperature, and specifically, under the condition of constant temperature, constant electrolyte thickness and area, the higher the moisture content, the stronger the carrier transport capacity of the electrolyte material, the larger the short-circuit output current, and the short-circuit output current and the moisture content present a power law relationship; under the condition of constant moisture content, constant electrolyte thickness and area, the higher the temperature, the stronger the carrier transport capacity of the electrolyte material, the larger the short-circuit output current, and the short-circuit output current and the temperature present an exponential relationship. Under the condition of constant temperature and constant moisture content, the larger the area of the electrolyte, the larger the short-circuit output current, the larger the thickness of the electrolyte, the smaller the short-circuit output current, and the short-circuit output current is proportional to the area of the electrolyte and inversely proportional to the thickness of the electrolyte.

[0044] Therefore, for a thermal battery with a monomer battery piece area S0 and an electrolyte thickness h0, the short-circuit output current in the unactivated state and the moisture content and temperature in the electrolyte material present the following relationship:

[0045] Y=a×{I0×exp[-c×(1 / T1-1 / T0)]×h0 / S0} b

[0046] Y=a×{I0×exp[-c×(1 / T1-1 / T0)]×h0 / S0}

[0047] The application is based on the short-circuit output current of the thermal battery in the unactivated state, and the non-linear electrolyte material moisture content calculation method can realize the detection of the electrolyte material moisture content of the thermal battery in the equipment level, which is fast, accurate, low in cost, non-destructive to the product, and can be detected on line, thereby solving the technical problems that the prior art cannot be accurately and non-destructively detected.

[0048] Embodiment 1

[0049] As shown in Figure 1 , the application is based on the current-based thermal battery electrolyte moisture content equipment level detection method, which comprises the following steps:

[0050] The short-circuit output current I0 of the thermal battery in the unactivated state in the equipment system is measured by using an ammeter, as shown in Figure 2 , and specifically, the positive and negative poles of the ammeter are respectively connected to the positive and negative poles of the thermal battery in the equipment system, and the short-circuit output current I0 of the thermal battery in the unactivated state at the measurement environment temperature T0 is measured, wherein 273K <= T0 <= 373K, and K is the absolute temperature unit of Kelvin.

[0051] According to the short-circuit output current I0, the electrolyte material moisture content of the thermal battery in the equipment is calculated by using a non-linear electrolyte material moisture content calculation method, and the calculation formula of the non-linear electrolyte material moisture content calculation method is as follows:

[0052] Y=a×{I0×exp[-c×(1 / T1-1 / T0)]×h0 / S0} b

[0053] Y=a×{I0×exp[-c×(1 / T1-1 / T0)]×h0 / S0}

[0054] As a further implementation, the equipment system comprises a thermal battery, electronic components, mechanical components and sensor components, and the thermal battery and the electronic components, mechanical components and sensor components are connected in series and in parallel.

[0055] As a further implementation, the electrolyte material of the thermal battery in the equipment system is a mixture of molten salt material and adsorption material in any ratio.

[0056] As a further implementation, the molten salt electrolyte is one of LiCl, KCl, LiF, LiBr, KBr, LiI, NaBr, LiNO3, KNO3, RbNO3, NaNO3, Li2CO3, Li2SO4, Li3PO4, or a solid solution or mixture formed by multiple materials.

[0057] As a further implementation, the adsorption material is MgO, Al2O3, Li7La3Zr2O 12 , SiO2, BN, etc. In particular implementation:

[0058] S10, dry or absorb moisture n parts of the same mass of electrolyte material, so that the water content of the electrolyte material is Y1, Y2, …, Yj, …, Yn respectively. Where j is an integer greater than 1 and less than n, 0 < Y1 < Y2 < … < Yj < … < Yn < 1.

[0059] S20, press the above n parts of electrolyte material and positive material, negative material into n parts of single battery piece with area S1 and electrolyte layer thickness h1. Wherein, the positive material is FeS2, Fe x Co 1-x S2, CoS2, V2O5, NiCl2, etc., and the negative material is LiB, LiSi, LiAl, LiIn, LiFe, etc.

[0060] S30, measure the short-circuit output current of the above n parts of single battery piece at ambient temperature T1, respectively I11, I12, …, I1j, …, I1n, wherein 273K <= T1 <= 373K.

[0061] S40, take I11, I12, …, I1j, …, I1n as independent variable I1, and Y1, Y2, …, Yj, …, Yn as dependent variable Y, and use Y = a x [I1 x h1 / S1] b to fit and get coefficients a and b.

[0062] S50, measure the short-circuit output current I21, I22, …, I2k, …, I2m of any single battery piece at ambient temperature T21, T22, …, T2k, …, T2m, wherein 273K <= T21 < T22 < … < T2k < … < T2m <= 373K, m is an integer greater than 2, and k is an integer greater than 0 and less than m.

[0063] S60, taking T21, T22, …, T2k, …, T2m as independent variable T2 and I21, I22, …, I2k, …, I2m as dependent variable I2, fitting by I2=d*exp(-c / T2) to obtain coefficient d and c.

[0064] S70, measuring the short circuit output current I0 of the thermal battery in the non-activated state in the equipment system at the test environment temperature T0, and calculating the moisture content Y in the electrolyte material by the following formula: Y=a*{I0*exp[-c*(1 / T1-1 / T0)]*h0 / S0} b , wherein S0 is the area of the thermal battery monomer cell sheet, and h0 is the thickness of the electrolyte material layer in the thermal battery monomer cell sheet.

[0065] The application can obtain the moisture content in the electrolyte material of the thermal battery connected to the system in real time based on the short circuit output current of the thermal battery in the non-activated state, has high speed, high measurement accuracy, low cost, no damage to the product, and can be detected on line and non-destructively.

[0066] Embodiment 2

[0067] As shown in Figure 1 and Figure 2 , the difference between the embodiment and embodiment 1 is that the thickness and area of the electrolyte of the thermal battery monomer cell sheet in the detection object are the same as the area and thickness of the monomer cell sheet in the pre-test, and the detection environment temperature is the same as the pre-test environment temperature.

[0068] The method comprises:

[0069] The short circuit output current I0 of the thermal battery in the non-activated state in the equipment system is measured by using an ammeter, as shown in Figure 2 , and specifically comprises: connecting the positive and negative poles of the ammeter with the positive and negative poles of the thermal battery in the equipment system respectively, measuring the short circuit output current I0 of the non-activated thermal battery at the environment temperature T0; wherein 273K<=T0<=373K.

[0070] According to the short circuit output current I0, the moisture content of the electrolyte material of the system-level thermal battery is calculated by using a non-linear electrolyte material moisture content calculation method; the calculation formula of the non-linear electrolyte material moisture content calculation method is:

[0071] Y=a*{I0*exp[-c*(1 / T1-1 / T0)]*h0 / S0} b

[0072] Wherein, Y is the moisture content of the system-level thermal battery electrolyte material, I0 is the short-circuit output current of the thermal battery in the equipped system in the unactivated state, a is the material process factor, b is the power index, c is the temperature conversion factor, S0 is the monomer battery piece area, h0 is the thickness of the electrolyte material layer in the monomer battery piece, T0 is the test environment temperature, T1 is the pre-test environment temperature, and exp is the exponential function with the natural constant e as the base.

[0073] In specific implementation:

[0074] S10, 8 parts of electrolyte material are hygroscopic, and the water content is 0.1%, 0.12%, 0.14%, 0.18%, 0.22%, 0.32%, 0.60%, and 0.86%, respectively.

[0075] S20, 8 parts of positive electrode material and 8 parts of negative electrode material are prepared, and the above-mentioned 8 parts of electrolyte material and the positive electrode material and the negative electrode material are respectively pressed into 8 parts of monomer battery pieces with an area of 8 cm 2 , and the thickness of the electrolyte layer is 0.08 cm.

[0076] S30, the short-circuit output current of the above-mentioned 8 parts of monomer battery pieces at 298K is measured, which is 4.8×10 -11 A, 1.4×10 -10 A, 1.7×10 -10 A, 1.3×10 -9 A, 5.3×10 -9 A, 1.9×10 -8 A, 6.1×10 -7 A, 2.1×10 -6 A.

[0077] S40, 4.8×10 -11 A, 1.4×10 -10 A, 1.7×10 -10 A, 1.3×10 -9 A, 5.3×10 -9 A, 1.9×10 - 8 A, 6.1×10 -7 A, 2.1×10 -6 A are taken as the independent variable I1, and 0.1%, 0.12%, 0.14%, 0.18%, 0.22%, 0.32%, 0.60%, and 0.86% are taken as the dependent variable Y, and Y=a×[I1×0.08 / 8] b are fitted to obtain the coefficients a=0.251 and b=0.195. As shown in Figure 3 , Figure 3Figure showing the relationship between short-circuit output current I1 of a thermal battery monomer cell and water content Y of electrolyte material at 298K in the present application.

[0078] S50, measure the short-circuit output current of a monomer cell with electrolyte moisture content of 0.22% at 298K, 308K, 318K, 328K and 338K, which are 5.3x10 -9 A, 1.2x10 -8 A, 2.6x10 -8 A, 5.4x10 -8 A, 1.1x10 -7 A.

[0079] S60, take 298K, 308K, 318K, 328K and 338K as independent variable T2, take 5.3x10 -9 A, 1.2x10 -8 A, 2.6x10 -8 A, 5.4x10 -8 A, 1.1x10 -7 A as dependent variable I2, and use I2=d x exp(-c / T2) for fitting, obtaining coefficients d=500 and c=7530. As shown in Figure 4 , Figure 4 Figure showing the relationship between short-circuit output current I2 of a monomer cell with electrolyte moisture content of 0.22% and measurement environment temperature T2 in the present application.

[0080] S70, measure the short-circuit output current of a certain monomer cell with area of 8cm 2 , electrolyte thickness of 0.08cm in a thermal battery in non-activated state at an environment temperature of 298K, which is 1.5x10 -9 A, calculate the moisture content Y in electrolyte material using the following formula, Y=0.251x{1.5x10 -9 x exp[-7530x(1 / 298-1 / 298)]x0.08 / 8} 0.195 =0.19%.

[0081] Example 3

[0082] As shown in Figure 1 and Figure 2 , the difference between this example and Example 1 is that the electrolyte thickness and area of the thermal battery monomer cell in the detection object are different from the area and thickness of the monomer cell in the pre-test, and the detection environment temperature is the same as the pre-test environment temperature.

[0083] In specific implementation:

[0084] S10. Eight portions of electrolyte material were hygroscopically treated to achieve water contents of 0.1%, 0.12%, 0.14%, 0.18%, 0.22%, 0.32%, 0.60%, and 0.86%, respectively.

[0085] S20. Prepare 8 portions of positive electrode material and 8 portions of negative electrode material respectively. Press the above 8 portions of electrolyte material, positive electrode material, and negative electrode material into shapes with an area of ​​8 cm². 2 Eight individual battery cells with an electrolyte layer thickness of 0.08 cm.

[0086] S30. Measure the short-circuit output current of the above 8 individual solar cells at 298K, which are 4.8 × 10⁻⁶. -11 A, 1.4 × 10 -10 A, 1.7 × 10 -10 A, 1.3×10 -9 A, 5.3 × 10 -9 A, 1.9 × 10 -8 A, 6.1×10 -7 A, 2.1×10 -6 A.

[0087] S40, with 4.8×10 -11 A, 1.4 × 10 -10 A, 1.7 × 10 -10 A, 1.3×10 -9 A, 5.3 × 10 -9 A, 1.9 × 10 - 8 A, 6.1×10 -7 A, 2.1×10 -6 A is the independent variable I1, and 0.1%, 0.12%, 0.14%, 0.18%, 0.22%, 0.32%, 0.60%, and 0.86% are the dependent variable Y. The formula is Y = a × [I1 × 0.08 / 8]. b By fitting the data, we obtained coefficients a = 0.251 and b = 0.195.

[0088] S50. The short-circuit output current of a single solar cell with an electrolyte moisture content of 0.22% was measured at 298K, 308K, 318K, 328K, and 338K, and was 5.3 × 10⁻⁶. -9 A, 1.2 × 10 -8 A, 2.6 × 10 -8 A, 5.4 × 10 -8 A, 1.1×10 -7 A.

[0089] S60, taking 298K, 308K, 318K, 328K and 338K as independent variable T2, and 5.3x10 -9 A as dependent variable I2, fitting with I2 = d x exp(-c / T2) to obtain coefficient d = 500 and c = 7530. -8 A, 2.6x10 -8 A, 5.4x10 -8 A, 1.1x10 -7 A as dependent variable I2, fitting with I2 = d x exp(-c / T2) to obtain coefficient d = 500 and c = 7530.

[0090] S70, measuring the short-circuit output current of a thermal battery in non-activated state with the area of the single cell being 32 cm 2 , and the thickness of the electrolyte in the single cell being 0.16 cm at the temperature of 298K. -7 A, calculating the moisture content Y in the electrolyte material with the following formula, Y = 0.251 x {3x10 -7 x exp[-7530 x (1 / 298 - 1 / 298)] x 0.16 / 32} 0.195 = 0.48%.

[0091] Example 4

[0092] As shown in Figure 1 and Figure 2 , the difference between this example and Example 1 is that the thickness and area of the electrolyte of the single cell of the thermal battery in the detection object are different from those of the single cell in the pre-test, and the detection environment temperature is different from the pre-test environment temperature.

[0093] In the implementation:

[0094] S10, absorbing moisture in 8 parts of electrolyte material to make the water content be 0.1%, 0.12%, 0.14%, 0.18%, 0.22%, 0.32%, 0.60% and 0.86% respectively.

[0095] S20, preparing 8 parts of positive material and 8 parts of negative material respectively, and pressing the above 8 parts of electrolyte material, positive material and negative material into 8 parts of single cell with the area being 8 cm 2 and the thickness of the electrolyte layer being 0.08 cm.

[0096] S30, measuring the short-circuit output current of the above 8 parts of single cell at 298K, which are 4.8x10 -11 A, 1.4x10 -10 A, 1.7x10 -10 A, 1.3x10 -9 A, 5.3x10 -9 A, 1.9x10 -8A, 6.1×10 -7 A, 2.1×10 -6 A.

[0097] S40, with 4.8×10 -11 A, 1.4 × 10 -10 A, 1.7 × 10 -10 A, 1.3×10 -9 A, 5.3 × 10 -9 A, 1.9 × 10 - 8 A, 6.1×10 -7 A, 2.1×10 -6 A is the independent variable I1, and 0.1%, 0.12%, 0.14%, 0.18%, 0.22%, 0.32%, 0.60%, and 0.86% are the dependent variable Y. The formula is Y = a × [I1 × 0.08 / 8]. b By fitting the data, we obtained coefficients a = 0.251 and b = 0.195.

[0098] S50. The short-circuit output current of a single solar cell with an electrolyte moisture content of 0.22% was measured at 298K, 308K, 318K, 328K, and 338K, and was 5.3 × 10⁻⁶. -9 A, 1.2 × 10 -8 A, 2.6 × 10 -8 A, 5.4 × 10 -8 A, 1.1×10 -7 A.

[0099] S60, using 298K, 308K, 318K, 328K, and 338K as independent variables T2, with 5.3 × 10 -9 A, 1.2 × 10 -8 A, 2.6 × 10 -8 A, 5.4 × 10 -8 A, 1.1×10 -7 A is used as the dependent variable I2. The coefficients d = 500 and c = 7530 are obtained by fitting the data using I2 = d × exp(-c / T2).

[0100] S70. The area of ​​a single solar cell measured at 308K is 32 cm². 2 The short-circuit output current of a hot battery in its unactivated state, with an electrolyte thickness of 0.16 cm in a single cell, is 3 × 10⁻⁶. -7 A. Calculate the moisture content Y in the electrolyte material using the following formula: Y = 0.251 × {3 × 10 -7 ×exp[-7530×(1 / 298-1 / 308)]×0.16 / 32} 0.195=0.42%.

[0101] Example 5

[0102] like Figure 5 As shown, the difference between this embodiment and Embodiment 1 is that this embodiment provides an equipment-level detection system for the moisture content of thermal battery electrolytes based on current. This system uses the equipment-level detection method for the moisture content of thermal battery electrolytes based on current in the above embodiments. The system includes:

[0103] The measuring unit is used to measure the short-circuit output current I0 of the thermal battery in the equipment system in the inactive state using an ammeter, including: connecting the positive and negative terminals of the ammeter to the positive and negative terminals of the thermal battery in the equipment system respectively, and measuring the short-circuit output current I0 of the inactive thermal battery at an ambient temperature T0; wherein, 273K<=T0<=373K;

[0104] The calculation unit is used to calculate the moisture content of the electrolyte material in the system-level thermal battery based on the short-circuit output current I0 using a nonlinear electrolyte material moisture content calculation method. The calculation formula for the nonlinear electrolyte material moisture content calculation method is as follows:

[0105] Y=a×{I0×exp[-c×(1 / T1-1 / T0)]×h0 / S0} b

[0106] Where Y is the moisture content of the electrolyte material of the system-level thermal battery, I0 is the short-circuit output current of the thermal battery in the equipment system in the inactive state, a is the material process factor, b is the power exponent, c is the temperature conversion factor, S0 is the area of ​​the single cell, h0 is the thickness of the electrolyte material layer in the single cell, T0 is the test environment temperature, T1 is the pre-test environment temperature, and exp is an exponential function with the natural constant e as the base.

[0107] The execution process of each unit can be carried out according to the equipment-level detection method of current-based thermal battery electrolyte moisture content in Example 1, and will not be described in detail in this example.

[0108] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An equipment-level detection method for the moisture content of electrolyte in a current-based thermal battery, characterized in that, The method includes: Measuring the short-circuit output current of the thermal battery in the equipment system in the unactivated state using an ammeter; Calculating the moisture content of the electrolyte material of the thermal battery according to the short-circuit output current by using the moisture content calculation method of the non-linear electrolyte material; The calculation formula of the moisture content calculation method of the non-linear electrolyte material is: ； where Y is the moisture content of the electrolyte material of the thermal battery, I0 is the short-circuit output current of the thermal battery in the equipment system in the unactivated state, a is the material process factor, b is the power exponent, c is the temperature conversion factor, S0 is the area of the single cell piece, h0 is the thickness of the electrolyte material layer in the single cell piece, T0 is the test environment temperature, T1 is the pre-test environment temperature, and exp is the exponential function with the natural constant e as the base; The acquisition methods of the material process factor, the power exponent, and the temperature conversion factor are: Step A: Drying or absorbing moisture from n portions of electrolyte materials with the same mass to make the water contents of the electrolyte materials be Y1, Y2, ……, Yj, ……, Yn respectively, where 0 < Y1 < Y2 < …… < Yj < …… < Yn < 1; where j is an integer greater than 1 and less than n; Step B: Pressing the above n portions of electrolyte materials together with the positive electrode material and the negative electrode material into n single cell pieces with an area of S1 and an electrolyte layer thickness of h1 respectively; Step C: Measuring the short-circuit output currents of the n single cell pieces in Step B at the environmental temperature T1, which are I11, I12, ……, I1j, ……, I1n respectively, where 273K <= T1 <= 373K; Step D: Using I11, I12, ..., I1j, ..., I1n as the independent variable I1, and Y1, Y2, ..., Yj, ..., Yn as the dependent variable Y, we use the formula Y = a × [I1 × h1 / S1]. b By performing a fitting operation, coefficients a and b are obtained; Step E: Measuring the short-circuit output currents I21, I22, ……, I2k, ……, I2m of any one of the single cell pieces in Step C at the environmental temperatures T21, T22, ……, T2k, ……, T2m respectively, where 273K <= T21 < T22 < …… < T2k < …… < T2m <= 373K, m is an integer greater than 2, and k is an integer greater than 0 and less than m; Step F: Using T21, T22, ……, T2k, ……, T2m as the independent variable T2 and I21, I22, ……, I2k, ……, I2m as the dependent variable I2, and fitting with I2 = d×exp(-c / T2) to obtain the coefficients d and c, where d is the pre-exponential factor of the temperature test and c is the temperature conversion factor.

2. The equipment-level detection method for the moisture content of thermal battery electrolyte based on current according to claim 1, characterized in that, The specific method of measuring the short-circuit output current of the thermal battery in the equipment system using an ammeter is: Connecting the positive and negative poles of the ammeter to the positive and negative poles of the thermal battery in the equipment system respectively, and measuring the short-circuit output current of the thermal battery in the unactivated state at the environmental temperature T0, where 273K <= T0 <= 373K.

3. The equipment-level detection method for the moisture content of thermal battery electrolyte based on current as described in claim 1, characterized in that, The equipment system includes a thermal battery, electronic components, mechanical components, and sensor components, and the thermal battery is connected in series and parallel with the electronic components, mechanical components, and sensor components.

4. The equipment-level detection method for the moisture content of thermal battery electrolyte based on current as described in claim 1, characterized in that, The electrolyte material of the thermal battery in the system is composed of a molten salt material and an adsorption material mixed in any proportion.

5. The equipment-level detection method for the moisture content of thermal battery electrolyte based on current according to claim 4, characterized in that, The molten salt electrolyte is a solid solution or mixture formed by one or more of LiCl, KCl, LiF, LiBr, KBr, LiI, NaBr, LiNO3, KNO3, RbNO3, NaNO3, Li2CO3, Li2SO4, Li3PO4.

6. The equipment-level detection method for the moisture content of thermal battery electrolyte based on current according to claim 4, characterized in that, The adsorbent material is MgO, Al2O3, or Li7La3Zr2O. 12 One or more of SiO2 and BN materials.

7. The equipment-level detection method for the moisture content of thermal battery electrolyte based on current according to claim 1, characterized in that, The positive electrode material in step B is FeS2. The anode material in step B is one or more of the following materials: CoS2, V2O5, and NiCl2. The anode material in step B is one or more of the following materials: LiB, LiSi, LiAl, LiIn, and LiFe.

8. An equipment-grade detection system for the moisture content of electrolyte in a current-based thermal battery, characterized in that, The system includes: A measurement unit for measuring the short-circuit output current of the thermal battery in the equipment system in the unactivated state using an ammeter, including: respectively connecting the positive and negative electrodes of the ammeter to the positive and negative electrodes of the thermal battery in the equipment system, and measuring the short-circuit output current of the unactivated thermal battery at the ambient temperature T0, where 273K <= T0 <= 373K; A calculation unit for calculating the moisture content of the electrolyte material of the system-level thermal battery according to the short-circuit output current using a non-linear electrolyte material moisture content calculation method; the calculation formula of the non-linear electrolyte material moisture content calculation method is: ； Where Y is the moisture content of the electrolyte material of the system-level thermal battery, I0 is the short-circuit output current of the thermal battery in the system in the unactivated state, a is the material process factor, b is the power exponent, c is the temperature conversion factor, S0 is the area of the single cell piece, h0 is the thickness of the electrolyte material layer in the single cell piece, T0 is the test ambient temperature, T1 is the pre-tested ambient temperature, and exp is the exponential function with the natural constant e as the base; The acquisition methods of the material process factor, power exponent, and temperature conversion factor are: Step A: Dry or absorb moisture from n portions of electrolyte materials with the same mass to obtain electrolyte materials with water contents of Y1, Y2,..., Yj,..., Yn respectively, where 0 < Y1 < Y2 <... < Yj <... < Yn < 1; where j is an integer greater than 1 and less than n; Step B: Press the above n portions of electrolyte materials together with the positive electrode material and the negative electrode material into n single cell pieces with an area of S1 and an electrolyte layer thickness of h1; Step C: Measure the short-circuit output currents of the n single cell pieces in Step B at the ambient temperature T1, which are I11, I12,..., I1j,..., I1n respectively, where 273K <= T1 <= 373K; Step D: Using I11, I12, ..., I1j, ..., I1n as the independent variable I1, and Y1, Y2, ..., Yj, ..., Yn as the dependent variable Y, we use the formula Y = a × [I1 × h1 / S1]. b By performing a fitting operation, coefficients a and b are obtained; Step E: Measure the short-circuit output currents I21, I22,..., I2k,..., I2m of any one of the single cell pieces in Step C at the ambient temperatures T21, T22,..., T2k,..., T2m, where 273K <= T21 < T22 <... < T2k <... < T2m <= 373K, m is an integer greater than 2, and k is an integer greater than 0 and less than m; Step F: Use T21, T22,..., T2k,..., T2m as the independent variable T2 and I21, I22,..., I2k,..., I2m as the dependent variable I2, and perform fitting using I2 = d×exp(-c / T2) to obtain the coefficients d and c, where d is the temperature test pre-factor and c is the temperature conversion factor.

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