Implanted optical fiber coating hydrogen sensor for battery, battery and energy storage device

Abstract

The utility model discloses an implantable optical fiber coating hydrogen sensor for battery, battery and energy storage device, including detection optical fiber, the detection optical fiber is provided with the cladding layer from grating detection area to the outside, the cladding layer includes the adhesion layer of complete cladding, the first protection layer, the reaction layer of partial cladding and the second protection layer in proper order. The implantable optical fiber coated hydrogen sensor for the battery solves the problems that a traditional BMS is poor in timeliness, the implantable sensor is poor in extreme environment tolerance, and the hydrogen sensitivity is prone to being affected, and the implantable optical fiber coated hydrogen sensor for the battery is good in hydrogen sensitivity, stability and timeliness.

Description

Technical Field

[0001] This utility model relates to the field of energy storage safety, specifically to an implantable fiber optic coated hydrogen sensor for batteries. Background Technology

[0002] The "dual-carbon" strategic goal has brought new development opportunities to the energy storage industry, and the installed capacity growth rate of new energy storage markets both domestically and internationally has shown a steady upward trend in recent years. As a crucial support for achieving the "dual-carbon" goal, new energy storage is expected to exceed 200GW by 2030, with lithium-ion batteries accounting for over 95% of this capacity. However, in recent years, energy storage battery safety accidents have occurred frequently. Fires and explosions caused by thermal runaway of energy storage batteries have caused serious harm to people, property, and the environment. Examples include the 2021 explosion at a Tesla energy storage station in Victoria, Australia, and the explosion at an energy storage station in Beijing. Due to the large number of lithium-ion batteries connected in series and parallel, their large scale, and high operating power, the safety risks and impacts of energy storage systems are more severe than those of electric vehicle power batteries. Therefore, as lithium-ion battery energy storage gradually advances towards the megawatt level, conducting research on thermal runaway and early warning systems for energy storage batteries is particularly important.

[0003] In lithium-ion batteries, deposited lithium dendrites react with polymers acting as binders to generate hydrogen gas. Therefore, the operating status of lithium-ion batteries in energy storage systems can be monitored by detecting hydrogen gas. Currently, energy storage battery systems primarily rely on Battery Management Systems (BMS) for battery health and safety management. However, current BMSs mainly use external battery data such as voltage, current, and temperature to sense the state of lithium-ion batteries and provide safety warnings. Methods relying on changes in current and voltage to determine safety are often unreliable and easily affected by battery type, capacity, and internal conditions. Furthermore, the diversity and complexity of thermal runaway lead to a lack of consistent patterns in voltage changes under these conditions, making it difficult to determine the battery's health and safety in practical applications. The emergence of implantable sensing technology effectively addresses these issues. Compared to traditional external sensing technologies, implantable sensing can monitor battery safety status more quickly and accurately. However, implantable sensing also presents its own challenges. Since implantable sensors typically operate inside the battery, they are susceptible to extreme environmental conditions. Existing implantable sensors often employ corrosion-resistant encapsulation materials to prevent damage from electrolytes and other environmental factors. While simple encapsulation and coating may improve the sensor's environmental tolerance to some extent, they can also affect signal acquisition and transmission. Therefore, ensuring both high tolerance to extreme environments and optimal hydrogen-sensing performance is a key direction for technological development. Utility Model Content

[0004] To address the problems existing in the prior art, this utility model proposes an implantable fiber optic coated hydrogen sensor for batteries and its preparation method. It solves the problems of poor timeliness of traditional BMS systems and weak tolerance of implantable sensors to extreme environments, which easily affects hydrogen sensitivity. The result is an implantable fiber optic coated hydrogen sensor for batteries with good hydrogen sensitivity, stability and timeliness.

[0005] In a first aspect, this utility model proposes an implantable fiber optic coated hydrogen sensor for batteries, including a detection fiber, wherein the detection fiber is provided with a cladding layer from the grating detection area outward, and the cladding layer sequentially includes a fully cladding adhesion layer, a first protective layer, a partially cladding reaction layer, and a second protective layer.

[0006] The coating layer consists of a fully coated nickel adhesion layer, a gold protective layer, a partially coated palladium alloy reaction layer, and a platinum protective layer, arranged sequentially from the grating detection area outwards.

[0007] The coating layer partially covers the first protective layer at a rate of 20%-80%.

[0008] The coverage rate of the partially coated reaction layer to the first protective layer is selected from 30% to 70%.

[0009] The coverage rate of the partially coated reaction layer to the first protective layer is selected from 40%-50%.

[0010] The implantable fiber-optic coated hydrogen sensor for the battery also includes a temperature-compensating fiber, wherein the grating detection area of ​​the detection fiber and its outward cladding layer are encapsulated together with the working area of ​​the temperature-compensating fiber.

[0011] As a further option, the thickness of the adhesion layer is selected from 100nm-200nm.

[0012] As a further option, the thickness of the adhesion layer is selected from 130nm-180nm.

[0013] As a further option, the thickness of the first protective layer is selected from 30nm-80nm.

[0014] As a further option, the thickness of the first protective layer is selected from 40nm-60nm.

[0015] As a further option, the thickness of the reaction layer is selected from 300nm-700nm.

[0016] As a further option, the thickness of the reaction layer is selected from 500nm-600nm.

[0017] As a further option, the thickness of the second protective layer is selected from 30nm-70nm.

[0018] As a further option, the thickness of the second protective layer is selected from 40nm-60nm.

[0019] Secondly, this utility model also provides a battery, including an implantable fiber optic coated hydrogen sensor disposed inside the battery.

[0020] As some preferred embodiments, the implantable fiber-optic coated hydrogen sensor for the battery can be disposed on the side of the battery core.

[0021] As some preferred embodiments, the battery comprises at least two cores, and the implanted fiber-optic coated hydrogen sensor for the battery is located at the geometric center of the core assembly.

[0022] As a further solution, the battery is led out of the pigtail from the encapsulated detection fiber and temperature compensation fiber through the pigtail opening, and the pigtail opening is sealed after the pigtail is led out.

[0023] As a further option, the fiber optic cable opening can be positioned between the safety valve and the positive electrode.

[0024] As a further option, the shape of the pigtail opening is selected from square, circle, triangle, rectangle, and N-sided polygon, where N is less than 20.

[0025] Thirdly, this utility model also provides an energy storage device, including an implantable fiber optic coated hydrogen sensor for a battery and a battery including the implantable fiber optic coated hydrogen sensor for the battery.

[0026] Compared with the prior art, the present invention has at least the following beneficial effects:

[0027] (1) In the detection fiber, from the grating detection area outwards, a fully covered adhesive layer, a first protective layer, a partially covered reaction layer, and a second protective layer are sequentially arranged. The adhesive layer enhances the adhesion between the fiber and the metal, preventing the upper metal layer from falling off. The introduction of the first protective layer effectively avoids the influence of electrolyte and hydrofluoric acid on the grating detection area and the adhesive layer, ensuring the stability of the sensor. The reaction layer is partially covered on the first protective layer. This design avoids the expansion cracking and stress problems that may be caused by full coverage, thereby improving the stability of the sensor and the hydrogen detection sensitivity. In addition, the second protective layer also adopts a partially covered form, which not only isolates the interference of gases such as carbon monoxide, but also prevents the electrolyte from eroding the reaction layer, avoiding expansion cracking and stress problems, while reducing production costs. Under the combined effect of the above-mentioned covering layers, we have significantly improved the resistance of the implantable fiber optic coated hydrogen sensor for batteries to extreme environments, and obtained an implantable fiber optic coated hydrogen sensor for batteries with high stability and hydrogen sensitivity.

[0028] (2) By encapsulating the grating detection area in the detection fiber and the working area of ​​the temperature compensation fiber together, accurate temperature detection is achieved, reducing the impact of temperature on the implantable fiber coated hydrogen sensor used in the battery, and further improving the accuracy of detection. Attached Figure Description

[0029] The accompanying drawings, which form part of this utility model, are used to provide a further understanding of the utility model. The illustrative embodiments of the utility model and their descriptions are used to explain the utility model and do not constitute an undue limitation of the utility model. In the drawings:

[0030] Figure 1 This is a cross-sectional view of the grating detection area 11;

[0031] Figure 2 The fabrication process of the detection optical fiber prepared in Example 1;

[0032] Figure 3 The image shown is a SEM image of fiber 1 after 24 hours of corrosion, prepared in Example 1.

[0033] Figure 4 SEM image of the fiber optic precursor prepared for Comparative Example 1 after 24 hours of corrosion detection.

[0034] Figure 5 Example 2, Comparative Example 2: Hydrogen detection diagram of an implantable fiber optic coated hydrogen sensor for battery prepared in comparison example 2.

[0035] Figure 6 The detection fiber electron microscope image prepared in Example 1;

[0036] Figure 7 The electron microscope image of the detection fiber prepared for Comparative Example 3;

[0037] Figure 8 This is a comparison chart of hydrogen gas from the implantable fiber optic coated hydrogen sensor for batteries in Example 2 and the fiber optic temperature-compensated detection in Comparative Example 4.

[0038] Figure 9 The hydrogen response time diagram of the implantable fiber optic coated hydrogen sensor for batteries prepared in Examples 1, 7, and 8 at a hydrogen concentration of 1%.

[0039] Figure 10 This is a diagram of the battery structure prepared in Example 2;

[0040] Figure 11 A cross-sectional view of the battery prepared in Example 2;

[0041] Figure 12 This is a structural diagram of the battery prepared in Example 9.

[0042] Among them, 1-detection optical fiber; 11-grating detection area; 12-adhesion layer; 13-first protective layer; 14-reaction layer; 15-second protective layer; 2-sleeve; 3-temperature compensation optical fiber; 4-core; 5-pigment opening; 6-implantable optical fiber coated hydrogen sensor for battery; 7-pigment. Detailed Implementation

[0043] For ease of understanding, the present invention will be described more comprehensively below, and embodiments of the present invention will be given, but this does not limit the scope of the present invention.

[0044] The following is a description of terms or words, and unless otherwise defined, all technical and scientific terms used herein have the meanings commonly understood by one skilled in the art to which this invention pertains.

[0045] In this article, the words “contain” and “include” and their various variations mean that other elements or wholes may be included but not specifically described.

[0046] In this article, the term "and / or" is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0047] In this paper, the term "working area" refers to the portion of the temperature-compensated fiber 3 used for actual measurement and monitoring of temperature changes, generally the area where the grating is located.

[0048] In this paper, the term "core group" refers to the total number of cores 4 contained inside the battery, which can contain Q cores, 2≤Q.

[0049] In a first aspect, this utility model proposes an implantable fiber-optic coated hydrogen sensor 6 for batteries, comprising a detection fiber 1 and a temperature compensation fiber 3, such as... Figure 1 The detection optical fiber 1 has a cladding layer extending outward from the grating detection area 11, which includes a fully cladding adhesion layer 12, a first protective layer 13, a partially cladding reaction layer 14, and a second protective layer 15. The grating detection area 11 and its outward cladding layer of the detection optical fiber 1 are encapsulated together with the working area of ​​the temperature compensation optical fiber 3 through a sleeve 2.

[0050] The gratings in optical fibers are sensitive to temperature changes. Fluctuations in ambient temperature can easily alter the grating pitch, affecting the strain response of fiber Bragg grating sensors. This is especially true when operating inside a battery, where significant temperature variations exist. Therefore, when using fiber Bragg grating strain sensors for accurate measurements, these environmental temperature changes must be fully considered. This solution, by encapsulating the sensing fiber and temperature compensation fiber 3 together, effectively monitors the temperature environment of the implanted fiber-coated hydrogen sensor 6 used in the battery. This reduces the impact of temperature changes on the signal transmitted through the sensing fiber, ensuring reliable data transmission under various environmental conditions.

[0051] In terms of stress resistance and corrosion resistance, in the implantable fiber-optic coated hydrogen sensor 6 used in batteries, the adhesion layer 12 on the surface of the grating detection area 11 can improve the adhesion between the optical fiber and the metal, preventing the upper metal layer from falling off. Secondly, the first protective layer 13 is disposed between the adhesion layer 12 and the partially covered reaction layer 14. The presence of the inert first protective layer 13 can effectively protect the internal grating detection area 11 and the adhesion layer 12 from the electrolyte and the hydrofluoric acid generated by the electrolyte, laying the foundation for the implantable fiber-optic coated hydrogen sensor 6 used in batteries. It is worth noting that, unlike the complete coverage of the first protective layer 13, the reaction layer 14 partially covers the surface of the first protective layer 13. This is because when the reaction layer 14 completely covers the surface of the first protective layer 13, the detection... During hydrogen measurement, expansion and cracking may occur, and these changes are easily offset by the surrounding stress. However, the partially coated reaction layer 14 in this solution can effectively avoid this situation. By partially coating the reaction layer 14, we can effectively improve the stability of the implantable fiber optic coated hydrogen sensor 6 used in the battery and optimize its sensitivity to detect hydrogen. Finally, we set a second protective layer 15 that is also partially coated on the surface of the partially coated reaction layer 14. The setting of the second protective layer 15 can isolate the influence of other gases such as carbon monoxide on the reaction layer 14, and can also act as a protective layer to prevent the electrolyte from corroding the reaction layer 14. In addition, the second protective layer 15 is also partially set, which helps to avoid cracking and stress offsetting problems caused by the expansion of the reaction layer 14, and saves costs.

[0052] Finally, the sleeve 2 helps to integrate the detection area 11 with the temperature compensation fiber 3, thereby improving the compensation for temperature and stress and preventing the heat and stress generated during battery operation from affecting the detection of the implanted fiber coated hydrogen sensor 6 used in the battery. On the other hand, the sleeve 2 also helps to ensure that the optical performance of the fiber is not contaminated and protects the encapsulated detection area 11 and the temperature compensation fiber 3 encapsulated in the sleeve 2, thereby improving the sensitivity and accuracy of the sensor.

[0053] As a further embodiment, the coverage rate of the partially coated reaction layer 14 over the first protective layer 13 is selected from 20% to 80%. The coverage rate refers to the percentage of the area covered by the covering material on the covered object relative to the total surface area of ​​the covered object. The partially coated reaction layer 14 helps to avoid the problem that the reaction layer 14 cannot offset the internal stress due to the expansion of the reaction layer 14 during the detection process due to the reaction with hydrogen. By partially coating the reaction layer 14, sufficient reaction space is provided for the expansion of the reaction layer 14 during the reaction, thereby improving the stability of the implantable fiber optic coated hydrogen sensor 6 used in the battery. When the coverage rate of the partially coated reaction layer 14 over the first protective layer 13 is selected from 20% to 80%, it helps to ensure that the expansion stress during the reaction is fully released on the basis of ensuring the reaction sensitivity, thereby improving the stability of the implantable fiber optic coated hydrogen sensor 6.

[0054] As a further option, the coverage rate of the partially coated reaction layer 14 over the first protective layer 13 is selected from 30% to 70%.

[0055] As a further option, the coverage rate of the partially coated reaction layer 14 to the first protective layer 13 is selected from 40% to 50%. When the coverage rate of the partially coated reaction layer 14 to the first protective layer 13 is selected from 40% to 50%, it helps to further optimize the hydrogen sensing performance of the implantable fiber coated hydrogen sensor 6 and improve the testing stability of the implantable fiber coated hydrogen sensor 6.

[0056] As a further solution, the adhesion layer 12 is used to improve the adhesion between the optical fiber and the metal. Therefore, the material of the adhesion layer is selected from non-precious metals with a hardness of less than 200 HV used for bonding, including any one of aluminum, zinc, nickel, and tin. The presence of the first protective layer 13 can effectively protect the optical fiber and the adhesion layer 12. Therefore, an inert metal that can isolate the electrolyte is selected as the first protective layer 13. The inert metal is selected from any one of gold, platinum, rhodium, iridium, osmium, and ruthenium. The reaction layer 14 is used to realize the detection of hydrogen. The material of the reaction layer 14 is selected from metals that can react with hydrogen, including any one of palladium metal and palladium alloy. The second protective layer 15 is set to protect the reaction layer 14 from the influence of other gases and electrolyte. The second protective layer 15 is selected from metals that can isolate the electrolyte and adsorb hydrogen, such as any one of platinum and platinum alloy.

[0057] As a further embodiment, the adhesion layer 12 is preferably nickel, the first protective layer 13 is preferably gold, the reaction layer 14 is preferably a palladium alloy, and the second protective layer 15 is preferably platinum; in this case, the detection optical fiber 1 is configured sequentially from the grating detection area 11 outwards as a fully covered nickel adhesion layer, a gold protective layer, a partially covered palladium alloy reaction layer, and a platinum protective layer.

[0058] When nickel is chosen as the material for the adhesive layer 12, in addition to its basic bonding function, its excellent thermal conductivity helps in precise temperature detection and control when used with the temperature-compensated optical fiber 3. When gold is used as the first protective layer 13, its inertness effectively protects the grating detection area 11 and the adhesive layer 12 from the effects of the electrolyte and hydrofluoric acid. Furthermore, compared to other materials, gold's unique flexibility provides ample buffering between the adhesive layer 12 and the reaction layer 14, thereby improving the stability of the implantable fiber-optic hydrogen sensor 6 used in the battery. Compared to palladium, when a palladium alloy is used as the reaction layer 14, the presence of the palladium alloy helps prevent hydrogen embrittlement. That is, when the temperature is less than 573K and the pressure is less than 2MPa, palladium absorbs hydrogen and forms... The film forms α-hydrogen-poor and β-hydrogen-rich phases with different lattice constants. During subsequent thermal cycling, the metal lattice expands and contracts, causing the film to become brittle or even break. On the other hand, other metals doped in palladium can further regulate the reaction rate of the palladium alloy and improve its sensitivity. Finally, when we use platinum as the second protective layer 15, on the one hand, the inert platinum metal can isolate the electrolyte and hydrofluoric acid from corroding the reaction layer 14 and avoid the influence of other gases such as carbon monoxide on the reaction layer 14. On the other hand, compared with other palladium alloys, platinum has a stronger hydrogen absorption capacity. Therefore, when platinum is used as the second protective layer 15, the reaction of the reaction layer 14 can be further optimized, and the hydrogen sensitivity performance of the implantable fiber optic coated hydrogen sensor 6 used in the battery can be improved.

[0059] As a further embodiment, the palladium alloy in the reaction layer 14 refers to an alloy material with palladium as the main element, fused with other metallic or non-metallic elements. In principle, the other elements or non-elements in the reaction layer 14 are not limited, and can be alloys formed from any one of the following metals: silver, gold, copper, platinum, zinc, nickel, iron, indium, tin, ruthenium, cobalt, manganese, aluminum, bismuth, magnesium, lead, antimony, chromium, tungsten, and lithium.

[0060] As a further embodiment, the palladium alloy contains more than 70% palladium metal.

[0061] As a further option, the palladium metal content in the palladium alloy is preferably 85%.

[0062] As a further embodiment, the palladium alloy is preferably a palladium-nickel alloy, wherein the palladium metal content is 90% and the nickel metal content is 10%. The presence of nickel in the palladium-nickel alloy helps to link the inner adhesion layer 12 and further regulate the adsorption and diffusion process of hydrogen in the palladium-nickel alloy. When the palladium metal content is 90% and the nickel metal content is 10%, it helps to further optimize the response time and sensitivity of the implantable fiber optic coated hydrogen sensor 6 used in the battery.

[0063] As a further option, the length of the optical fiber detection area 11 is selected from 5-11 mm.

[0064] As a further option, the thickness of the adhesion layer 12 is selected from 100nm-200nm.

[0065] As a further embodiment, the thickness of the adhesion layer 12 is selected from 130nm-180nm, for example, it can be any one of 130nm, 135nm, 140nm, 145nm, 150nm, 155nm, 160nm, 165nm, 170nm, 175nm, and 180nm.

[0066] As a further option, the thickness of the first protective layer 13 is selected from 30nm-80nm.

[0067] As a further option, the thickness of the first protective layer 13 is selected from 40nm-60nm, for example, it can be any one of 40nm, 45nm, 50nm, 55nm, and 60nm.

[0068] As a further option, the thickness of the reaction layer 14 is selected from 300nm-700nm.

[0069] As a further option, the thickness of the reaction layer 14 is selected from 500nm-600nm, for example, it can be any one of 500nm, 550nm, and 600nm.

[0070] As a further option, the thickness of the second protective layer 15 is selected from 30nm-70nm.

[0071] As a further option, the thickness of the second protective layer 15 is selected from 40nm-60nm, for example, it can be any one of 40nm, 45nm, 50nm, 55nm, and 60nm.

[0072] As some preferred embodiments, the length of the optical fiber detection area 11 is selected from 6 mm, the thickness of the adhesion layer 12 is selected from 150 nm, the thickness of the first protective layer 13 is selected from 50 nm, the thickness of the reaction layer 14 is selected from 600 nm, and the thickness of the second protective layer 15 is selected from 50 nm. When the length of the optical fiber detection area 11 is selected as 6 mm, it helps to provide clearer feedback when detecting changes in hydrogen gas inside the battery. The 150 nm adhesion layer 12 helps to better achieve the bonding between the optical fiber and the metal. The first protective layer 13 is set to 50 nm, which not only protects the internal optical fiber and the adhesion layer 12, but also serves as a better buffer layer to fully relieve the stress between the reaction layer 14 and the adhesion layer 12. The 600 nm reaction layer 14 greatly improves the sensitivity to hydrogen gas, optimizes the hydrogen sensing effect of the implantable optical fiber coated hydrogen sensor 6 for the battery, and further relieves the stress during the reaction. Finally, the 50 nm second protective layer 15 can optimize the cost and improve the hydrogen sensing performance of the implantable optical fiber coated hydrogen sensor 6 for the battery while avoiding the influence of other gases on the implantable optical fiber coated hydrogen sensor 6 for the battery.

[0073] As a further option, the length of the sleeve 2 is matched with the grating detection area 11.

[0074] As a further option, the grating in the grating detection area 11 is selected from any one of the following: Bragg grating, long-period grating, reflective grating, ultrashort grating, and phase-doped grating.

[0075] As a further option, the center wavelength of the detection optical fiber 1 is selected from any one of 1310nm, 1550nm, 1545nm, and 1625nm.

[0076] As a further option, the bandwidth of the detection fiber 1 is selected from 0.300 nm.

[0077] As a further option, the side-mode suppression ratio of the detection fiber 1 is selected from 10dB-30dB.

[0078] As a further embodiment, the reflectivity of the detection fiber 1 is greater than 80.00%.

[0079] As a further improvement, the reflectivity of the detection fiber 1 is greater than 90%. A reflectivity greater than 90% helps to better select specific wavelengths, thereby further optimizing the transmission of the signal from the implanted fiber-coated hydrogen sensor 6 used in the battery and avoiding attenuation.

[0080] As some preferred options, the detection fiber 1 can be selected with a center wavelength of 1545nm, a bandwidth of 0.300nm, a side-mode rejection ratio of 11dB, a grating length of 5mm, and a reflectivity of 90.00% to further optimize signal transmission and improve the hydrogen sensing performance of the fiber-coated hydrogen sensor.

[0081] As a further option, the type of temperature-compensating fiber 3 is not limited in principle. For example, it can be selected from any one of the following: Bragg grating-based sensor, fluorescent fiber temperature sensor, gallium arsenide semiconductor crystal absorption sensor, Raman / Brillouin scattering sensor, element-type fiber temperature sensor, and transmission-type fiber temperature sensor.

[0082] As a preferred option, the temperature-compensating fiber 3 can be selected with the same parameters as the detection fiber 1. Selecting the same parameters as the detection fiber 1 helps to provide a more accurate indication of temperature regulation, thereby improving the stability of the implantable fiber-optic coated hydrogen sensor 6 used in the battery.

[0083] As a further option, the sleeve 2 is made of either plastic or ceramic material.

[0084] As a further option, the plastic material is selected from any one of polyimide, polyvinyl chloride, polyethylene, polytetrafluoroethylene, and polyetheretherketone.

[0085] As a further option, the ceramic material is selected from any one of alumina, zirconium oxide, silicon carbide, silicon nitride, aluminum zirconium oxide, and boron carbide.

[0086] Secondly, this utility model also provides a battery (such as...) Figure 10 , 12 This includes an implantable fiber-optic coated hydrogen sensor 6 installed inside the battery. By placing the implantable fiber-optic coated hydrogen sensor 6 inside the battery, real-time monitoring of the hydrogen concentration inside the battery is achieved, which helps to promptly detect potential risks or other safety hazards and to respond promptly to the internal conditions of the battery.

[0087] As some preferred embodiments, the implantable fiber optic coated hydrogen sensor 6 for the battery can be disposed on the side of the battery core 4. The implantable fiber optic coated hydrogen sensor 6 for the battery disposed on the side can monitor the area near the edge, which is suitable for detecting local hydrogen leakage or changes in gas concentration in concentrated areas. At the same time, placing the implantable fiber optic coated hydrogen sensor 6 for the battery on the side can also achieve more convenient installation.

[0088] As some preferred embodiments, the battery comprises at least two cores 4, and the implantable fiber-optic coated hydrogen sensor 6 for the battery is disposed at the geometric center of the core assembly. Although the sensor located at the geometric center of the battery may be subject to greater stress than the edge position, the hydrogen in the battery is typically generated by the reaction of polymer binders and lithium dendrites. The generated hydrogen does not rise directly to the top of the prismatic battery, but rather exists as bubbles between the cores 4. Therefore, by placing the implantable fiber-optic coated hydrogen sensor 6 for the battery at the geometric center of the core assembly, compared to placing it on the side, the geometric center position is usually the location with the most uniform gas distribution within the battery, allowing the sensor to more comprehensively monitor the hydrogen concentration of the entire battery. At the same time, the presence of the coating layer of the implantable fiber-optic coated hydrogen sensor 6 for the battery helps to fully protect the detection fiber and avoid the influence of stress on the implantable fiber-optic coated hydrogen sensor 6 for the battery. Therefore, placing the implantable fiber-optic coated hydrogen sensor 6 for the battery at the geometric center further improves the sensitivity of the implantable fiber-optic coated hydrogen sensor 6 for the battery to hydrogen, enabling early detection of hydrogen.

[0089] As a further solution, the pigtail 7 led out from the sleeve 2 leads out the battery through the pigtail opening 5, and the pigtail opening 5 is closed after leading out the pigtail 7.

[0090] As a further option, the fiber optic opening 5 can be positioned between the safety valve and the positive electrode.

[0091] As a further option, the material of the closed pigtail opening 5 can be selected from any one of epoxy resin, polyimide, polyimide, polyfluorinated polyethylene, polyetheretherketone resin, and polyester resin.

[0092] As a further option, the shape of the pigtail opening 5 is selected from square, circle, triangle, rectangle, and N-sided polygon, where N is less than 20.

[0093] Thirdly, this utility model also provides a method for preparing an implantable optical fiber coated hydrogen sensor 6 for batteries, the preparation steps of which are as follows:

[0094] S1: Remove the cladding layer on the grating surface of the optical fiber, clean off the oil stains, and then treat it with a mixed solution of palladium chloride and hydrochloric acid to obtain an optical fiber precursor with grating detection area 11.

[0095] S2: The adhesive layer 12 material and the first protective layer 13 material are sequentially coated onto the grating detection area 11. Then, the reaction layer 14 material and the second protective layer 15 material are sequentially coated onto the first protective layer 13 to obtain the grating detection area 11 with the coating layer.

[0096] S3: The working area of ​​the grating detection region 11 with the cladding layer and the temperature compensation fiber 3 are encapsulated in the sleeve 2 to obtain the implantable fiber coated hydrogen sensor 6 for the battery.

[0097] As a further option, in step S1, the method of removing the cladding layer on the surface of the grating in the optical fiber is not limited, and technicians can choose the appropriate removal method according to their needs.

[0098] As a further solution, the method for removing oil stains in step S1 is to soak the grating part in sodium hydroxide solution, followed by soaking in deionized water.

[0099] As a further option, the concentration of the sodium hydroxide solution is selected from 3% to 8%.

[0100] As a further option, the soaking time in the sodium hydroxide solution is selected from 20 min to 50 min.

[0101] As a further option, the soaking time in deionized water is selected from 0.5 min to 3 min.

[0102] After removing the oil stains, the grating surface was treated with a mixed solution of palladium chloride and hydrochloric acid. On the one hand, hydrochloric acid, as a strong acid, can effectively remove impurities and organic matter from the surface, further cleaning the fiber surface and providing a clean environment for the subsequent adhesion layer 12 to be fixed and promoting the optimization of the fiber surface by palladium chloride. On the other hand, we believe that treating the fiber surface with palladium chloride may further increase the active sites and assist the subsequent adhesion layer 12 to be bonded.

[0103] As a further option, the concentration of palladium chloride in step S1 is selected from 0.2 g / L to 0.5 g / L.

[0104] As a further option, the concentration of hydrochloric acid in step S1 is selected from 2 mL / L to 5 mL / L.

[0105] As a further option, the treatment time for the mixed solution of palladium chloride and hydrochloric acid in step S1 is 5 min to 15 min.

[0106] As a further option, the method for coating with nickel, gold, or partially palladium alloys and platinum is not limited in principle, and can be selected from any of the following: electroplating, chemical plating, physical vapor deposition, chemical vapor deposition, laser deposition, and evaporation. Electroplating refers to depositing metal ions onto the surface of an optical fiber through an electrolytic reaction. This method can control the thickness of the metal layer and form a uniform metal film on the fiber surface. Chemical plating refers to depositing a metal layer on the fiber surface using a chemical reaction, forming a uniform metal cladding layer without the need for an external current. Physical vapor deposition involves converting metal into a gaseous phase and then condensing it on the fiber surface to form a cladding layer; this method can obtain a high-quality metal film. Chemical vapor deposition typically deposits metal compounds onto the fiber surface through a gas-phase reaction, suitable for forming a uniform and dense metal cladding layer. Laser deposition refers to directly depositing metal powder or thin films onto the fiber surface using laser energy to form a metal cladding layer. Evaporation is a technique that uses heating in a vacuum environment to evaporate materials and form a metal cladding layer on a substrate.

[0107] As some preferred embodiments, in step S2, both the adhesive layer 12 material and the first protective layer 13 material are coated by vapor deposition, wherein the vacuum is 5×10⁻⁶. -3 kPa, rotation speed of 10 r / min, and evaporation rate selected from 0.3-0.8 nm / s.

[0108] As some preferred embodiments, in step S2, the reaction layer 14 material is coated by vapor deposition, wherein the vacuum is 5 × 10⁻⁶. -3 kPa, rotation speed of 10 r / min, when the material of reaction layer 14 is selected from palladium, the evaporation rate of palladium is selected from 0.27-0.72 nm / s.

[0109] As some preferred embodiments, in step S2, when the material of the reaction layer 14 is selected from palladium alloy, the evaporation rate of palladium is selected from 0.27-0.72 nm / s, and the evaporation rate of other metals is selected from 0.03-0.08 nm / s.

[0110] As some preferred embodiments, in step S2, the material of the second protective layer 15 is coated by vapor deposition, wherein the vacuum is 5×10⁻⁶. -3 kPa, rotation speed of 10 r / min, and evaporation rate selected from 0.3-0.8 nm / s.

[0111] As a further option, the packaging method in step S3 is not limited, and technicians can choose the appropriate packaging method according to their needs.

[0112] The chemical raw materials used in the following examples and comparative examples are all prior art and were obtained commercially. The experimental apparatus and testing equipment used in the following examples and comparative examples are all conventional equipment in the art, and there are no special requirements or limitations.

[0113] Example 1

[0114] Fabrication of detection fiber 1

[0115] First, the surface cladding layer of the grating portion in the detection fiber 1 was scraped off using a stripper. Then, the grating portion was soaked in a 5% sodium hydroxide solution for 30 minutes and then soaked in deionized water for 1 minute. After soaking, the grating portion was immersed in a mixed solution of 0.3 g / L palladium chloride and 3 mL / L hydrochloric acid for 10 minutes and then removed to obtain the detection fiber precursor.

[0116] The processed optical fiber was then fixed on the optical fiber rotating device located in the evaporation chamber of the evaporation coating machine. Nickel, gold, palladium, and platinum evaporation materials were then placed into the evaporation boats, respectively. A vacuum was then evacuated, reducing the chamber pressure to 5 × 10⁻⁶. -3 At kPa, with the rotation speed set to 10 r / min, rotate the evaporation baffle to the position of the evaporation boat containing the nickel evaporation material and begin evaporation at a rate of 0.5 nm / s. Observe the film thickness gauge and stop evaporation after the evaporation thickness reaches 150 nm. Switch the evaporation baffle to the position of the evaporation boat containing the gold evaporation material and begin evaporation at a rate of 0.5 nm / s. Observe the film thickness gauge and stop evaporation after the evaporation thickness reaches 50 nm. Switch the evaporation baffle to the position of the evaporation boat containing the palladium and nickel evaporation materials, turn off the fiber optic rotation device, switch the evaporation baffle to the position of the evaporation boat containing the palladium evaporation material, and begin evaporation at a rate of 0.3 nm / s. Then switch the evaporation baffle to the position of the evaporation boat containing the nickel evaporation material and evaporate at a rate of 0.05 nm / s, controlling the evaporation rate of palladium to nickel to be 9:1. Observe the film thickness gauge and stop evaporation after the evaporation thickness reaches 600 nm. Switch the evaporation baffle to the position of the evaporation boat where the platinum evaporation material is placed, and set the evaporation rate to 0.5 nm / s. Stop evaporation after observing the film thickness gauge and finding that the evaporation thickness is 50 nm.

[0117] Conduct corrosion resistance tests; the test procedures are detailed in the test method.

[0118] Example 2 (Best)

[0119] Fabrication of an implantable fiber optic coated hydrogen sensor 6 for use in batteries:

[0120] The detection fiber 1 was prepared using the same method and steps as in Example 1. Then, the grating detection area 11 and the temperature compensation fiber 3 were passed through the sleeve 2. Hot melt adhesive was applied to the openings at both ends of the sleeve 2. After the hot melt adhesive solidified, the two ends of the sleeve were placed on a heat-sealing machine for heat sealing, resulting in an implantable fiber-optic coated hydrogen sensor 6 for use in batteries.

[0121] Assembly of the battery, including the implantable fiber-optic coated hydrogen sensor 6 for the battery:

[0122] LiFePO4 was used as the positive electrode active material, graphite as the negative electrode active material, and PE coated with CCS on both sides as the separator with a total thickness of 20μm. After coating the positive and negative electrode active materials, the cells were wound up. A fiber-optic coated hydrogen sensor was placed at the geometric center of the two cells. The wound cells were then welded together and initially packaged, followed by laser welding of the top cover. LiPF6 electrolyte was injected into the cells and fully wetted. Formation and aging treatments were then performed. A second electrolyte injection was performed, and sealing pins were welded to obtain the battery.

[0123] Tests were conducted on the implantable fiber optic coated hydrogen sensor for the battery, including hydrogen permeability testing. The test procedures are described in the test method.

[0124] Example 3

[0125] The preparation method is the same as in Example 2, except that palladium is used instead of palladium-nickel alloy.

[0126] Example 4

[0127] The preparation method is the same as in Example 2, except that a palladium-silver alloy is used instead of a palladium-nickel alloy.

[0128] Example 5

[0129] The preparation method is the same as in Example 2, except that the ratio of palladium to nickel alloy is 8:2.

[0130] Example 6

[0131] The preparation method is the same as in Example 2, except that the ratio of palladium to nickel alloy is 7:3.

[0132] Example 7

[0133] The preparation method is the same as in Example 2, except that the thickness of the palladium-nickel alloy layer is 700 nm. The response test of the implanted fiber optic coated sensor 6 is performed, and the test steps are described in the test method.

[0134] Example 8

[0135] The preparation method is the same as in Example 2, except that the thickness of the palladium-nickel alloy layer is 500 nm. The response test of the implanted fiber optic coated sensor 6 is performed, and the test steps are described in the test method.

[0136] Example 9

[0137] The preparation method is the same as in Example 2, except that the optical fiber coated hydrogen sensor is placed in the gap between the two battery cells.

[0138] Comparative Example 1

[0139] The fiber precursor was prepared in the same manner as in Example 1, and corrosion resistance was tested. The test steps are described in the test method.

[0140] Comparative Example 2

[0141] The preparation method is the same as in Example 2, except that the adhesion layer 12 is not vapor-deposited.

[0142] Comparative Example 3

[0143] The preparation method is the same as in Example 2, except that the adhesion layer 12 is replaced with titanium.

[0144] Comparative Example 4

[0145] The preparation method is the same as in Example 2, except that no compensation fiber is set.

[0146] Comparative Example 5

[0147] The preparation method is the same as in Example 2, except that the ratio of palladium to nickel alloy is 1:1.

[0148] Test methods

[0149] Corrosion resistance test

[0150] In a glove box, the detection fiber 1 prepared in Example 1 and the product prepared in Comparative Example 1 were placed in a glass bottle containing LiPF6 electrolyte. The initial temperature of the constant temperature chamber was set to 25°C, and after 1 hour, the temperature was raised to 60°C. After holding for 30 minutes, the temperature was lowered to 25°C after 1 hour, and held for 30 minutes. After cycling for 24 hours, the samples were taken out and characterized by SEM.

[0151] 6 Tests on Implantable Fiber Optic Coated Hydrogen Sensor for Batteries

[0152] First, the packaged square battery was charged to full capacity using a constant current of 0.5C and left to stand for 30 minutes. Then, the square battery was charged to a constant current of 0.3C until it bulged slightly, and then the charging was stopped. The voltage, temperature, and wavelength changes of the implanted fiber optic hydrogen sensor used in the battery were measured during the test.

[0153] Response test of implanted fiber optic coated sensor 6

[0154] The implantable fiber optic coated sensor 6 prepared in Example 2 and the implantable fiber optic coated sensor 6 prepared in Comparative Example 2 were placed in a calibration gas chamber, and a nitrogen-hydrogen mixture with a concentration of 1% was introduced to obtain the response map of the implantable fiber optic coated sensor 6.

[0155] Table 1

[0156] Adhesion layer 12 material Reaction layer 14 material Alloy reaction layer 14 ratio Thickness of alloy reaction layer 14 (nm) Sensor position Should compensation fiber be installed? Example 1 \ \ \ \ \ \ Example 2 nickel Palladium-nickel alloy 9:1 600 Geometric Center yes Example 3 nickel palladium \ 600 Geometric Center yes Example 4 nickel Palladium-silver alloy 9:1 600 Geometric Center yes Example 5 nickel Palladium-nickel alloy 8:2 600 Geometric Center yes Example 6 nickel Palladium-nickel alloy 7:3 600 Geometric Center yes Example 7 nickel Palladium-nickel alloy 9:1 700 Geometric Center yes Example 8 nickel Palladium-nickel alloy 9:1 500 Geometric Center yes Example 9 nickel Palladium-nickel alloy 9:1 600 Cell gap yes Comparative Example 1 \ \ \ \ \ \ Comparative Example 2 \ Palladium-nickel alloy 9:1 600 Geometric Center yes Comparative Example 3 titanium Palladium-nickel alloy 9:1 600 Geometric Center yes Comparative Example 4 nickel Palladium-nickel alloy 9:1 600 Geometric Center no Comparative Example 5 nickel Palladium-nickel alloy 1:1 600 Geometric Center yes

[0157] Table 2

[0158] <![CDATA[Hydrogen permeability (cm 3 cm -1 s -1 )]]> Hydrogen sensor response speed (s) Example 1 \ \ Example 2 2.51 20 Example 3 1.83 36 Example 4 2.46 25 Example 5 2.46 24 Example 6 1.86 32 Example 7 2.52 18 Example 8 2.5 22 Example 9 2.5 26 Comparative Example 1 \ \ Comparative Example 2 0.87 46 Comparative Example 3 \ \ Comparative Example 4 \ \ Comparative Example 5 0.15 \

[0159] From Table 2, Figure 3-9 It can be observed that Examples 1-9 exhibit hydrogen permeability and sensor response speed that are far superior to Comparative Examples 1-5.

[0160] Figures 3-4 The images show SEM images of the detection fiber 1 prepared in Example 1 and the detection fiber precursor prepared in Comparative Example 1 after being etched in the electrolyte for 24 hours. Figure 3 , Figure 4 It can be clearly observed that, compared to Example 1, traces of peeling can be observed on the surface of Comparative Example 1 without a protective layer, while no obvious changes were observed in Example 1 with a protective layer and an adhesive layer 12. This indicates that the setting of the first protective layer 13 and the second protective layer 15 on the surface of the detection fiber 1 can effectively protect the grating detection area 11, the adhesive layer 12 and the reaction layer 14 of the detection fiber 1, thereby resisting the corrosion of the electrolyte.

[0161] Examples 1-2 and Comparative Examples 2-3 demonstrate the function of the adhesive layer 12. As can be observed from Comparative Examples 2-3, whether the adhesive layer 12 is absent or titanium is used to replace nickel as the adhesive layer 12, Comparative Examples 2-3 are severely affected in terms of hydrogen permeability and response speed. When the adhesive layer 12 is not provided, as... Figure 5 Example 2, Comparative Example 2, shows the hydrogen detection pattern of the implantable fiber optic coated hydrogen sensor for batteries, prepared by [unclear - possibly a data source]. Figure 5 It can be observed that the wavelength change in Example 2, which has an adhesive layer 12, is significantly more pronounced than that in Comparative Example 2, which does not have an adhesive layer 12. This may be because, in addition to its adhesive function, the adhesive layer 12, when nickel is used as the adhesive layer, can further assist the reaction of the reaction layer 14, thereby increasing the hydrogen sensitivity of the implantable fiber optic coated hydrogen sensor 6 used in the battery. However, when titanium is used to replace nickel as the adhesive layer 12... Figure 6-7 The following are electron microscope images of the detection fiber optic cable after 24 hours of etching, as shown in Example 1 and Comparative Example 3. Figure 6 It can be clearly observed that, compared to Example 1, the electron micrograph of Comparative Example 3 ( Figure 7 The first protective layer 13 shows obvious corrosion marks, which may be because titanium cannot firmly bond the first protective layer 13 as the adhesive layer 12. Therefore, the first protective layer 13 may partially peel off. The partial peeling of the first protective layer 13 may cause corrosion of the inner adhesive layer 12 and the optical fiber detection area, thus presenting a mottled morphological feature.

[0162] Example 2, Comparative Example 4, also demonstrates the role of temperature-compensated fiber optic 1 in the implanted fiber-optic coated hydrogen sensor 6 used in the battery, by... Figure 8It can be observed that when the temperature compensation fiber 3 is not set, the hydrogen sensitivity performance of Comparative Example 4 is significantly worse than that of Example 1. This is because temperature is also one of the factors that cause grating fluctuations. The setting of temperature compensation fiber 3 helps to shield the influence of temperature on the sensor, thereby improving the hydrogen sensitivity.

[0163] Example 2 and Comparative Example 5 demonstrate the effect of the ratio of palladium to mixed metal in the alloy on the implantable fiber-optic coated hydrogen sensor 6 used in the battery when the reaction layer 14 is an alloy. Both Example 2 and Comparative Example 5 use a palladium-nickel alloy, the difference being that the ratio of palladium to nickel in Example 2 is 9:1, while in Comparative Example 5 it is 1:1. When hydrogen permeability and response speed tests were performed, the hydrogen permeability in Comparative Example 5 was only 0.15, while the hydrogen permeability in Example 2 could reach 2.51, while exhibiting a response speed of 20s. This may be because although using a palladium alloy as the reaction layer 14 can optimize the reaction efficiency, when the ratio of mixed metal in the alloy is higher than 30%, it may hinder hydrogen permeation and affect the response of the hydrogen sensor.

[0164] Examples 2-4 discuss the influence of the material of the reaction layer 14 on the hydrogen sensing performance of the implantable fiber optic coated hydrogen sensor 6 used in the battery. As can be observed from Examples 2-4, compared with using elemental palladium as the material of the reaction layer 14, Examples 2 and 4, which use an alloy as the material of the reaction layer 14, exhibit better hydrogen permeability and response speed. This may be because the presence of mixed metals in the alloy can avoid hydrogen embrittlement, improve hydrogen permeability, and thus optimize the reaction rate.

[0165] The ratio of alloys in reaction layer 14 also affects the performance of the implantable fiber optic coated hydrogen sensor 6 used in the battery. As observed in Examples 2, 5, and 6, when the ratio of palladium to nickel alloy is 7:3, the hydrogen permeability and response speed of Examples 2 and 5 are significantly better. Further increasing the palladium content, when the ratio of palladium to nickel alloy is 9:1, Example 2 exhibits excellent hydrogen permeability and response speed. When the ratio of palladium to nickel alloy is greater than 8:2, the reaction effect of reaction layer 14 can be further optimized, improving the hydrogen sensing performance of the implantable fiber optic coated hydrogen sensor 6 used in the battery.

[0166] We also discussed the thickness of the reaction layer 14. In Examples 2, 7, and 8, optimizing the thickness of the reaction layer 14 may lead to an improvement in hydrogen permeability and the response speed of the hydrogen sensor, but it is also accompanied by an increase in recovery time. Figure 11 Example 2 showed the best recovery ability and good response speed. Therefore, according to Examples 2, 7 and 8, the thickness of the reaction layer 14 can be preferably 500nm-600nm.

[0167] Finally, we also discussed the impact of the implantation location on the performance of the implantable fiber-optic coated hydrogen sensor 6 used in batteries, such as... Figure 12 As can be observed in Examples 2 and 9, Example 2 exhibits a higher hydrogen response speed than Example 9. This may be because the implantable fiber optic coated hydrogen sensor 6 for the battery, located at the geometric center of the core assembly, can detect the generation of hydrogen more promptly and thus respond. Therefore, according to Examples 2 and 9, it is preferable to locate the implantable fiber optic coated hydrogen sensor 6 for the battery at the geometric center of the core assembly.

[0168] The technical features of the embodiments described above can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make modifications, alterations, substitutions, and variations to the above embodiments within the scope of the present invention. Furthermore, without contradiction, those skilled in the art can combine and integrate different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

Claims

1. An implantable fiber optic coated hydrogen sensor for batteries, characterized in that, The detection fiber (1) is provided with a cladding layer from the grating detection area (11) outward. The cladding layer includes a fully covered adhesive layer (12), a first protective layer (13), a partially covered reaction layer (14), and a second protective layer (15).

2. The implantable fiber optic coated hydrogen sensor for a battery according to claim 1, characterized in that, The coating layer consists of a fully coated nickel adhesion layer, a gold protective layer, a partially coated palladium alloy reaction layer, and a platinum protective layer, arranged sequentially from the grating detection area (11) outwards.

3. The implantable fiber optic coated hydrogen sensor for a battery according to claim 1, characterized in that, The coating layer (14) partially covers the first protective layer (13) with a coating rate selected from 20% to 80%; The coverage rate of the partially coated reaction layer (14) over the first protective layer (13) is selected from 30% to 70%; The coating rate of the partially coated reaction layer (14) over the first protective layer (13) is selected from 40% to 50%.

4. The implantable fiber optic coated hydrogen sensor for a battery according to claim 1, characterized in that, The implantable fiber-optic coated hydrogen sensor for the battery also includes a temperature-compensating fiber (3), and the grating detection area (11) of the detection fiber (1) and its outward cladding layer are encapsulated together with the working area of ​​the temperature-compensating fiber (3).

5. The implantable fiber optic coated hydrogen sensor for a battery according to claim 1, characterized in that, The thickness of the adhesion layer (12) is selected from 100nm-200nm; The thickness of the first protective layer (13) is selected from 30nm-80nm; The thickness of the reaction layer (14) is selected from 300nm-700nm; The thickness of the second protective layer (15) is selected from 30nm-70nm.

6. The implantable fiber optic coated hydrogen sensor for a battery according to claim 1, characterized in that, The thickness of the adhesion layer (12) is selected from 130nm-180nm; The thickness of the first protective layer (13) is selected from 40nm-60nm; The thickness of the reaction layer (14) is selected from 500nm-600nm; The thickness of the second protective layer (15) is selected from 40nm-60nm.

7. A battery, characterized in that, Includes the implantable fiber optic coated hydrogen sensor for a battery as described in any one of claims 1-6, wherein the implantable fiber optic coated hydrogen sensor (6) for the battery is disposed inside the battery.

8. The battery according to claim 7, characterized in that, The implantable fiber-optic coated hydrogen sensor (6) for the battery is disposed on the side of the battery core (4).

9. The battery according to claim 7, characterized in that, The battery comprises at least two cores (4), and the implantable fiber-optic coated hydrogen sensor (6) for the battery is located at the geometric center of the core assembly. The pigtail (7) drawn from the encapsulated detection fiber (1) and temperature compensation fiber (3) leads out the battery through the pigtail opening (5), and the pigtail (7) is closed after being drawn out from the pigtail opening (5). The fiber optic opening (5) can be located between the safety valve and the positive electrode; The shape of the pigtail opening (5) is selected from square, circle, triangle, rectangle, and N-sided polygon, where N is less than 20.

10. An energy storage device, characterized in that, Includes the implantable fiber optic coated hydrogen sensor for a battery as described in any one of claims 1-6 and the battery as described in claims 7-9.

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