Batteries, battery systems and sensors

Abstract

A battery, a battery system and a sensor, wherein the battery comprises at least one battery cell, each battery cell has a first surface and a second surface opposite to each other, and the battery cell comprises: a first opening, which is opened on the first surface and communicates with the inside of the battery cell; a cover, which is arranged on the first surface, and a receiving cavity is formed in the cover and a second opening is opened; a connecting portion, at least a part of which is accommodated in the receiving cavity, a first through hole is opened in the connecting portion, the first through hole communicates with the first opening and the second opening, a second through hole is opened on the connecting portion, and the second through hole communicates with the first through hole; a sensing portion, which is attached to the wall of the connecting portion forming the first through hole, and the projection of the second through hole falls into the area surrounded by the sensing portion; an optical fiber, which has a first end and a second end opposite to each other, wherein the first end is accommodated in the second through hole to transmit a test optical signal to the sensing portion and receive a feedback optical signal, and the feedback optical signal is used to characterize the pressure and / or temperature of the battery cell. Thus, the safety monitoring of a single battery cell can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and in particular to a battery, a battery system and a sensor. Background Art

[0002] In recent years, with the rapid development of the electrochemical energy storage market and the power battery market, battery thermal runaway, fire and explosion have become the biggest pain point in the field of energy storage safety. Safety hazards have become the biggest obstacle for industrial and commercial energy storage to cover a large area of ​​densely populated urban core areas and commercial and service facilities.

[0003] At present, the early warning management system for batteries is mainly the battery management system (BMS, i.e. Battery Management System), which collects and analyzes the current, voltage and resistance of the entire battery (such as a pack, cluster, pile, station including multiple cells) to conduct a safety assessment of the overall characteristics of the battery. However, the existing technology has low accuracy in battery safety monitoring, which has caused safety hazards during use. Summary of the invention

[0004] The technical problem solved by the present invention is how to monitor the safety of a single battery cell.

[0005] To solve the above technical problems, an embodiment of the present invention provides a battery, the battery comprising at least one battery cell, wherein each of the battery cells has a first surface and a second surface opposite to each other along a first direction, and the battery cell comprises: a first opening, which is opened on the first surface and communicates with the interior of the battery cell; a cover, which is arranged on the first surface and at least covers the first opening, wherein a receiving cavity is formed in the cover and a second opening is opened on the surface facing the first surface; a connecting portion, wherein at least a part of the connecting portion is accommodated in the receiving cavity, the connecting portion is provided with a first through hole extending along the first direction, the first through hole communicates with the first opening and the second opening, and the connecting portion is provided with a second through hole extending along the second direction, the second through hole communicates with the first through hole, wherein the second direction is perpendicular to the first direction; a sensing portion, which is attached to a wall of the connecting portion forming the first through hole, wherein a projection of the second through hole along the second direction falls into an area surrounded by the sensing portion; an optical fiber, wherein along the extending direction, the optical fiber has a first end and a second end opposite to each other, wherein the first end is accommodated in the second through hole to transmit a test optical signal to the sensing portion and receive a feedback optical signal, wherein the feedback optical signal is used to characterize the pressure and / or temperature of the battery cell.

[0006] Optionally, the battery further comprises: an explosion-proof valve movably covered on a side of the second opening away from the first opening, wherein the explosion-proof valve can be pushed open by gas overflowing from the first through hole.

[0007] Optionally, the battery further includes: a core inserted into the first end of the optical fiber and accommodated in the second through hole, wherein an outer surface of the core inserted is in contact with an inner wall of the second through hole.

[0008] Optionally, the sensing part includes: a base, which is attached to the connecting part to form the wall of the first through hole; and a diaphragm, which is arranged at the end of the base away from the optical fiber, and a sealed cavity is formed between the base and the diaphragm, and the diaphragm is suitable for generating corresponding deformation according to the pressure change of the gas in the first through hole, and the feedback light signal carries the deformation information of the diaphragm.

[0009] Optionally, a high reflectivity film is attached to the surface of the membrane facing the base.

[0010] Optionally, the base includes: a plate portion made of glass; a first ring portion supported between the plate portion and the diaphragm, and the plate portion, the first ring portion and the diaphragm together form the sealed cavity.

[0011] Optionally, a semi-transparent and semi-reflective film is attached to the surface of the plate portion facing the membrane, and the plate portion is suitable for forming a resonant cavity, and a feedback optical signal passing through the resonant cavity carries temperature information of the battery cell.

[0012] Optionally, the sensing portion further includes: a second ring portion, the second ring portion is arranged on a side of the diaphragm away from the first ring portion, and the diaphragm is clamped between the first ring portion and the second ring portion.

[0013] Optionally, a thickness of a wall of the second ring portion on a side close to the diaphragm is greater than a thickness of a wall of the second ring portion on a side away from the diaphragm.

[0014] Optionally, the connecting part includes: a connecting column, the first through hole and the second through hole are formed on the connecting column, and the end of the connecting column facing away from the first surface is in contact with the cover portion; and a connecting plate connected to the outer peripheral surface of the connecting column, and the connecting plate is in contact with and fixed to the first surface.

[0015] Optionally, along a plane perpendicular to the first direction, a cross-sectional area of ​​the first through hole is smaller than an opening area of ​​the first opening, and the connecting plate closes a portion of the first opening that exceeds the first through hole.

[0016] Optionally, the cover is connected to the first surface via the connecting plate, and the accommodating cavity is surrounded by the cover and the connecting plate.

[0017] Optionally, the battery further includes: a sealing structure, disposed between the connecting plate and the first surface, and / or, disposed between the connecting column and the cover.

[0018] Optionally, the battery also includes: a connector having a third end and a fourth end relative to each other, wherein the third end is used to receive the second end of the optical fiber; a coupler having a fifth end and a sixth end relative to each other, wherein the fifth end is coupled to the fourth end, and the sixth end is suitable for pluggable connection with an optoelectronic device.

[0019] Optionally, the fifth end is accommodated in the accommodating cavity, and a third opening is formed on the side wall of the cover portion, and the third opening is used to expose the sixth end.

[0020] In order to solve the above technical problems, the present application also provides a battery system, comprising: the above-mentioned battery; a transmitting module, which is optically coupled with the optical fiber of each battery cell in the battery, and the transmitting module is used to transmit a test optical signal to the optical fiber; a signal processing module, which is optically coupled with the optical fiber of each battery cell in the battery, and the signal processing module is used to receive the feedback optical signal output by the optical fiber, and obtain a detection result based on the feedback optical signal, and the detection result includes the temperature data and / or pressure data of the battery cell.

[0021] In order to solve the above technical problems, the present application also provides a sensor for detecting the temperature and / or pressure of a battery cell of a battery, wherein the battery cell is provided with a first opening opening toward a first direction, and the sensor comprises: a cover portion, which is detachably arranged on the outer surface of the battery cell and at least covers the first opening, wherein the surface of the cover portion facing the first direction is provided with a second opening, and an accommodating cavity is formed inside the cover portion; a connecting portion, wherein at least a part of the connecting portion is accommodated in the accommodating cavity, wherein the connecting portion is provided with a first through hole extending along the first direction, wherein the first through hole connects the first opening and the second opening, and wherein the connecting portion is provided with a second through hole extending along the second direction, wherein the second through hole connects the first through hole, wherein the second direction is perpendicular to the first direction; a sensing portion, which is attached to a wall of the connecting portion forming the first through hole, wherein the projection of the second through hole along the second direction falls into an area surrounded by the sensing portion; an optical fiber, wherein along the extension direction, the optical fiber has a first end and a second end opposite to each other, wherein the first end is accommodated in the second through hole to transmit a test optical signal to the sensing portion and receive a feedback optical signal, wherein the feedback optical signal is used to characterize the pressure and / or temperature of the battery cell.

[0022] Compared with the prior art, the technical solution of the embodiment of the present invention has the following beneficial effects:

[0023] To solve the above technical problems, an embodiment of the present invention provides a battery, the battery comprising at least one battery cell, wherein each of the battery cells has a first surface and a second surface opposite to each other along a first direction, and the battery cell comprises: a first opening, which is opened on the first surface and communicates with the interior of the battery cell; a cover, which is arranged on the first surface and at least covers the first opening, wherein a receiving cavity is formed in the cover and a second opening is opened on the surface facing the first surface; a connecting portion, wherein at least a part of the connecting portion is accommodated in the receiving cavity, the connecting portion is provided with a first through hole extending along the first direction, the first through hole communicates with the first opening and the second opening, and the connecting portion is provided with a second through hole extending along the second direction, the second through hole communicates with the first through hole, wherein the second direction is perpendicular to the first direction; a sensing portion, which is attached to a wall of the connecting portion forming the first through hole, wherein a projection of the second through hole along the second direction falls into an area surrounded by the sensing portion; an optical fiber, wherein along the extending direction, the optical fiber has a first end and a second end opposite to each other, wherein the first end is accommodated in the second through hole to transmit a test optical signal to the sensing portion and receive a feedback optical signal, wherein the feedback optical signal is used to characterize the pressure and / or temperature of the battery cell.

[0024] By adopting the technical solution described in the present application, the temperature and pressure of the gas in the first through hole are monitored in real time or spot-checked, so that the temperature change and pressure change inside each battery cell can be independently and accurately monitored or spot-checked, thereby improving the safety of the entire battery system. Even if a battery cell has a problem, it can be quickly located and corresponding measures can be taken to avoid affecting the performance of the entire battery pack.

[0025] Furthermore, the technical solution of the present invention does not require changing the original structure of the battery cell. It only requires adding a cover, a connecting part, a sensing part and an optical fiber between the original battery cell and the explosion-proof valve. This can effectively monitor the working status of the battery cell without affecting the explosion-proof performance of the explosion-proof valve. It has wide applicability and high reliability.

[0026] Furthermore, the present invention still retains the design of the explosion-proof valve, which can be movably covered on the side of the second opening away from the first opening. The explosion-proof valve can be used as a last resort to prevent the battery cell from exploding, and the explosion-proof airway of the explosion-proof valve reuses the first through hole. Therefore, while not affecting the explosion-proof performance, this solution can also achieve reliable monitoring of the safe operation of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of a battery according to an embodiment of the present invention;

[0028] Figure 2 yes Figure 1 Schematic diagram of the battery cell;

[0029] Figure 3 yes Figure 2 Exploded view of the battery cell;

[0030] Figure 4 yes Figure 2 Cross-sectional view along AA direction;

[0031] Figure 5 yes Figure 3 Schematic diagram of the connecting part and the sensing part;

[0032] Figure 6 yes Figure 2 Exploded view of the sensor;

[0033] Figure 7 yes Figure 2 A schematic diagram of the middle cover;

[0034] Figure 8 yes Figure 4 Schematic diagram of the middle sensory unit;

[0035] Fig. 9 Schematic diagram of a battery system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0036] As mentioned in the background technology, the existing battery early warning management system (such as the BMS system) monitors the current and voltage at the smallest unit, the battery pack (Pack) level, which cannot meet the safety requirements for the health management of each battery cell throughout the battery life cycle, and cannot involve the health status monitoring, prediction and management of each battery cell.

[0037] Specifically, after investigating and analyzing the prior art, the inventor believes that in the prior art that determines the abnormal operation of the battery by current, voltage, etc., the current, voltage, etc. belong to the indirect signal processing and analysis with lag, because once the battery operates abnormally (caused by abnormal electrochemical mechanism, etc.), its direct manifestation is the sharp increase in air pressure and temperature in the closed internal space of the battery cell, thereby affecting the output of "electricity" by the battery cell. In various prior arts that use sensors for monitoring, it is also impossible to involve the monitoring, prediction and management of the health status of each battery cell. This leads to the fact that in the application scenario of monitoring the temperature changes of batteries with a large number of batteries, the temperature obtained may be the average value of multiple batteries. Even if it is determined that the battery is abnormal, it is still necessary to further investigate the specific battery cell, which is complicated. Moreover, during the investigation process, other batteries are also in a non-working state, which seriously affects the work efficiency.

[0038] In addition, there are also solutions in the prior art that attach single-point electrical temperature sensors and resistance films based on the "Wheatstone bridge" principle to the outer surface of the battery cell to monitor the temperature and deformation of the battery cell (the change in internal pressure of the battery cell causes the deformation of the surface of the battery cell). Although this solution has already involved the monitoring of battery cells, due to the electromagnetic environment, its signal-to-noise ratio is poor, the signal is easily interfered, and the signal wire topology is more complex (multi-channel detection is required). There is also a risk of "electricity" leakage, so it is difficult to popularize.

[0039] In order to solve the above technical problems, the embodiments of the present invention provide a battery, a battery system and a sensor, wherein the battery includes at least one battery cell, wherein each of the battery cells has a first surface and a second surface opposite to each other along a first direction, and the battery cell includes: a first opening, which is opened on the first surface and communicates with the interior of the battery cell; a cover portion, which is arranged on the first surface and at least covers the first opening, wherein a receiving cavity is formed in the cover portion and a second opening is opened on the surface facing the first surface; a connecting portion, wherein at least a part of the connecting portion is accommodated in the receiving cavity, and the connecting portion is provided with a first through hole extending along the first direction, and the first through hole communicates with the first battery cell; The first opening and the second opening, the connecting part is provided with a second through hole extending along a second direction, the second through hole is connected to the first through hole, wherein the second direction is perpendicular to the first direction; the sensing part is attached to the wall of the connecting part forming the first through hole, the projection of the second through hole along the second direction falls into the area surrounded by the sensing part; the optical fiber has a first end and a second end opposite to each other along the extension direction, wherein the first end is accommodated in the second through hole to transmit a test light signal to the sensing part and receive a feedback light signal, the feedback light signal is used to characterize the pressure and / or temperature of the battery cell.

[0040] By adopting the technical solution described in the present application, the temperature and pressure of the gas in the first through hole are monitored in real time or spot-checked, so that the temperature change and pressure change inside each battery cell can be independently and accurately monitored or spot-checked, thereby improving the safety of the entire battery. Even if a battery cell has a problem, it can be quickly located and corresponding measures can be taken to avoid affecting the performance of the entire battery or battery pack.

[0041] Furthermore, the technical solution of the present invention does not require changing the original structure of the battery cell. It only requires adding a cover, a connecting part, a sensing part and an optical fiber between the original battery cell and the explosion-proof valve. While not affecting the explosion-proof performance of the explosion-proof valve, it can also achieve effective monitoring of the working status of the battery cell. It has wide applicability and high reliability.

[0042] Furthermore, the present invention still retains the design of the explosion-proof valve, which can be movably covered on the side of the second opening away from the first opening. The explosion-proof valve can be used as a last resort to prevent the battery cell from exploding, and the explosion-proof airway of the explosion-proof valve reuses the first through hole. Therefore, while not affecting the explosion-proof performance, this solution can also achieve reliable monitoring of the safe operation of the battery cell.

[0043] In order to make the above-mentioned objects, features and beneficial effects of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0044] Figure 1 is a schematic diagram of a battery 100 according to an embodiment of the present invention; Figure 2 yes Figure 1 A schematic diagram of a battery cell 10; Figure 3 yes Figure 2 Exploded view of the battery cell; Figure 4 yes Figure 2 Cross-sectional view along the AA direction.

[0045] Combination Figures 1 to 4 The battery 100 includes at least one battery cell 10, wherein each of the battery cells 10 has a first surface 101 and a second surface (not shown in the figure) opposite to each other along a first direction D1, and the battery cell 10 includes: a first opening 1, which is opened on the first surface 101 and communicates with the interior of the battery cell 10; a cover 2, which is arranged on the first surface 101 and at least covers the first opening 1, and a receiving cavity 21 is formed in the cover 2 and a second opening 22 is opened on the surface facing the first surface 101; a connecting portion 3, at least a part of the connecting portion 3 is accommodated in the receiving cavity 21, and the connecting portion 3 is provided with a first through hole 31 extending along the first direction D1, and the first through hole 31 communicates with the first opening 1 and the A second opening 22, a second through hole 32 extending along a second direction D2 is formed on the connecting portion 3, and the second through hole 32 is connected to the first through hole 31, wherein the second direction D2 is perpendicular to the first direction D1; a sensing portion 4, attached to a wall of the connecting portion 3 forming the first through hole 31, and a projection of the second through hole 32 along the second direction D2 falls into an area surrounded by the sensing portion 4; an optical fiber 5, along an extending direction, the optical fiber 5 has a first end 51 and a second end 52 opposite to each other, wherein the first end 51 is accommodated in the second through hole 32 to transmit a test light signal to the sensing portion 4 and receive a feedback light signal, and the feedback light signal is used to characterize the pressure and / or temperature of the battery cell 10.

[0046] The first direction D1 may be, for example, a direction from the first opening 1 to the second opening 22. The second direction D2 may be, for example, a direction from the outside of the first through hole 31 to the inside of the first through hole 31.

[0047] Specifically, refer to Figure 1 The battery 100 may include, for example, a housing 1001, wherein the housing 1001 defines a receiving space. Further, at least one battery cell 10 may be received in the receiving space.

[0048] In some non-limiting embodiments, the plurality of battery cells 10 may be arranged in an array of multiple rows and columns. Figure 1 As shown, the battery 100 may include 16 battery cells 10, which are arranged in two rows, wherein each row may have 8 battery cells 10. Furthermore, a partition 1002 may be provided between adjacent battery cells 10.

[0049] In some embodiments, a heat insulating material may be disposed on the partition 1002 , thereby preventing heat transfer between adjacent battery cells 10 and preventing a faulty high-temperature battery cell 10 from affecting adjacent battery cells 10 .

[0050] Further, refer to Figure 2 , the battery cell 10 has a first surface 101 and a second surface (not shown in the figure) opposite to each other along a first direction D1. The electrode 102 of the battery cell 10 is arranged on the first surface 101, and through the electrode 102, the battery cell 10 can be connected to the power supply circuit to supply power to an external electrical device. In some embodiments, the electrode 102 may, for example, include an anode (corresponding to the electrode marked with "+" in the figure, also called a positive electrode) and a cathode (corresponding to the electrode marked with "-" in the figure, also called a negative electrode).

[0051] Further, combined with Figures 2 to 4 The battery cell 10 includes a first opening 1, which is opened on the first surface 101. Through the first opening 1, when the battery cell 10 is in an abnormal working state, gas is easily generated inside the battery cell 10 or the temperature of the battery cell 10 increases, resulting in excessive pressure inside the battery cell 10, which is prone to serious production accidents such as explosion. Through the first opening 1, the gas generated inside the battery cell 10 or expanded by heat can escape to the outside of the battery cell 10, effectively avoiding the occurrence of accidents such as explosion of the battery cell 10.

[0052] Furthermore, each of the battery cells 10 is also provided with a sensor 300 , which is used to monitor the pressure and / or temperature of the corresponding battery cell 10 .

[0053] Furthermore, the sensor 300 may include: a cover portion 2 , and the cover portion 2 is disposed on the first surface 101 .

[0054] In some embodiments, the cover 2 can be fixed to the first surface 101 by a fixing member 104 .

[0055] Furthermore, the cover 2 covers the first opening 1 . Also, a receiving cavity 21 is formed in the cover 2 .

[0056] Furthermore, a second opening 22 is formed on the surface of the cover 2 facing the first surface 101. The second opening 22 is communicated with the first opening 1.

[0057] Furthermore, the sensor 300 may further include a connecting portion 3 , at least a portion of which is accommodated in the accommodating cavity 21 .

[0058] Furthermore, the connecting portion 3 defines a first through hole 31. Along the first direction D1, the first through hole 31 communicates with the first opening 1 and the second opening 22.

[0059] Furthermore, the connecting portion 3 is further provided with a second through hole 32 . The second through hole 32 extends along a second direction D2 , wherein the second direction D2 is perpendicular to the first direction D1 . Furthermore, the second through hole 32 is connected to the first through hole 31 .

[0060] In some embodiments, the second through hole 32 is opened on the wall of the connecting portion 3 forming the first through hole 31 .

[0061] Furthermore, the sensor 300 also includes a sensing unit 4 and an optical fiber 5 .

[0062] In some embodiments, the sensing unit 4 may be, for example, a MOMP (Micro Opto-Mechanical Pressure) chip.

[0063] refer to Figure 4 and Figure 5 , the sensing part 4 is located inside the first through hole 31. Moreover, the sensing part 4 is attached to the inner wall of the first through hole 31. Further, the sensing part 4 closes the opening of the second through hole 32 toward the first through hole 31. The sensing part 4 can obtain the pressure and / or temperature of the gas in the first through hole 31 in real time, so as to achieve real-time monitoring of the safe use status of the battery cell 10.

[0064] In some embodiments, a limiting portion 35 may be further provided on the inner wall of the first through hole 31 , and the limiting portion 35 may be provided close to the sensing portion 4 to limit the relative displacement between the sensing portion 4 and the inner wall of the first through hole 31 , thereby ensuring that the sensing portion 4 can be stably attached to the inner wall of the first through hole 31 .

[0065] In some embodiments, the sensing unit 4 may also be attached to the inner wall of the first through hole 31 by gluing or the like to ensure the sealing effect of the opening of the second through hole 32 toward the first through hole 31 and ensure the sealing inside the battery cell 10 .

[0066] Furthermore, the projection of the second through hole 32 along the second direction D2 falls into the area surrounded by the sensing portion 4 .

[0067] In a preferred embodiment, the second direction D2 may be perpendicular to the plane where the sensing portion 4 is located.

[0068] Furthermore, the first end 51 of the optical fiber 5 is accommodated in the second through hole 32 , and the first end 51 of the optical fiber 5 faces the sensing part 4 .

[0069] In some embodiments, the first end 51 of the optical fiber 5 can transmit a test optical signal to the sensing unit 4 and receive a feedback optical signal fed back by the sensing unit 4. By demodulation or other analysis methods, the temperature and pressure information of the corresponding battery cell 10 represented by the feedback optical signal can be obtained.

[0070] Furthermore, since the projection of the second through hole 32 along the second direction D2 falls into the area surrounded by the sensing portion 4, the test light signal emitted by the optical fiber 5 through the second through hole 32 can be accurately irradiated onto the sensing portion 4. The sensing portion 4 can respond to state changes (such as pressure and / or temperature changes) inside the battery cell 10 and convert these changes into changes in the light signal, namely, the feedback light signal.

[0071] As described above, by adopting the technical solution described in the present application, the temperature and pressure of the gas in the first through hole 31 are monitored in real time or randomly checked, so that the temperature change and pressure change inside each battery cell 10 can be independently and accurately monitored or randomly checked, thereby improving the safety of the entire battery 100. Even if a problem occurs in a battery cell 10, it can be quickly located and corresponding measures can be taken to avoid affecting the performance of the entire battery 100 or even the battery pack.

[0072] In some embodiments, in combination Figures 2 to 6 The battery 100 may further include: an explosion-proof valve 6 movably covered on a side of the second opening 22 away from the first opening 1 , and the explosion-proof valve 6 can be opened by the gas overflowing from the first through hole 31 .

[0073] Specifically, the explosion-proof valve 6 is a safety element in the battery 100. When the pressure inside the battery cell 10 abnormally rises to a dangerous level, the explosion-proof valve 6 can provide a mechanism to release the pressure, thereby preventing the battery cell 10 from exploding. For example, when a large amount of gas is generated inside the battery cell 10 due to some reasons (such as overcharging, short circuit, thermal runaway, etc.) and the pressure rises sharply, the explosion-proof valve 6 will be pushed open to allow the gas to be quickly discharged, thereby reducing or eliminating the risk of explosion.

[0074] Furthermore, the explosion-proof valve 6 can be movably covered on the side of the second opening 22 away from the first opening 1. That is, the explosion-proof valve 6 can be set on the side of the cover 2 away from the battery cell 10. The explosion-proof valve 6 can move or deform under certain conditions (such as increased internal pressure), thereby opening a channel to allow the gas inside the battery cell 10 to be discharged. At the same time, since the explosion-proof valve 6 is located on the side of the second opening 22 away from the first opening 1, the explosion-proof valve 6 will not hinder the gas in the battery cell 10 from escaping from the first opening 1 to the first through hole 31. Inside the first through hole 31, the sensing part 4 and the optical fiber 5 cooperate to obtain the pressure and temperature information of the gas, thereby realizing the monitoring of the internal state of the battery cell 10.

[0075] Furthermore, the first through hole 31 can also serve as an explosion-proof air passage of the explosion-proof valve 6 .

[0076] Furthermore, the battery 100 further includes: a core insert 7 which is sleeved on the first end 51 of the optical fiber 5 and accommodated in the second through hole 32 , and the outer surface of the core insert 7 is in contact with the inner wall of the second through hole 32 .

[0077] Specifically, the ferrule 7 can ensure accurate docking and stable connection between the optical fiber 5 and the second through hole 32 .

[0078] In some embodiments, the ferrule 7 can be made of ceramic or metal, and is sleeved on the outside of the first end 51 of the optical fiber 5 to enhance the strength of the first end 51, so as to prevent the optical fiber from bending or being damaged when the first end 51 is inserted into the second through hole 32, thereby affecting the transmission of the test optical signal and the feedback optical signal. In addition, the ferrule 7 provides a precise positioning and fixing point for the first end 51 of the optical fiber 5. By inserting the first end 51 of the optical fiber 5 into the ferrule 7 and ensuring that the ferrule 7 is tightly fitted with the inner wall of the second through hole 32, it can be ensured that the optical fiber 5 remains stable when transmitting the optical signal, and the transmission quality of the signal will not be affected by vibration or displacement.

[0079] In some embodiments, an optical collimator may also be disposed outside the first end 51 of the optical fiber 5 to ensure that the optical fiber 5 is aligned with the membrane 42 .

[0080] Further, refer to Figure 8 The sensing part 4 includes: a base 41, which is attached to the connecting part 3 to form the wall of the first through hole 31; a diaphragm 42, which is arranged at the end of the base 41 away from the optical fiber 5, and a sealed cavity is formed between the base 41 and the diaphragm 42. The diaphragm 42 is suitable for generating corresponding deformation according to the pressure change of the gas in the first through hole 31, and the feedback light signal carries the deformation information of the diaphragm 42.

[0081] Specifically, the base 41 is the basic part of the sensing part 4 , and the base 41 is closely attached to the wall of the first through hole 31 formed on the connecting part 3 , so that the sensing part 4 is stably and firmly disposed inside the first through hole 31 as a whole.

[0082] Furthermore, the base 41 is also used to support the diaphragm 42. The diaphragm is arranged at one end of the base 41 away from the optical fiber 5. A sealed cavity is formed between the diaphragm 42 and the base 41. When the gas pressure inside the battery cell 10 changes, the diaphragm 42 will produce corresponding deformation according to the change in gas pressure, and this deformation is a direct reflection of the change in the internal state (such as pressure, temperature, etc.) of the battery cell 10. At the same time, the deformation of the diaphragm 42 will also change the optical properties (such as refractive index, optical path, etc.) in the sealed cavity, thereby affecting the test light signal emitted by the optical fiber 5 to the sensing unit 4.

[0083] In some embodiments, the diaphragm 42 may be made of semiconductor materials such as silicon nitride or single crystal silicon. Further, the thickness of the diaphragm 42 is relatively small to achieve a high sensitivity response to the pressure change inside the battery cell 10 .

[0084] In some embodiments, the thickness and diameter of the diaphragm 42 can be designed according to different measurement range requirements, wherein the thickness can range from a few microns to hundreds of microns, and the diameter is generally in the micron or millimeter order.

[0085] In some embodiments, the sealed cavity can be a standard air chamber. For example, the sealed cavity can be a vacuum environment, or filled with a certain amount of air, that is, an environment with a certain air pressure (for example, a standard atmospheric pressure). As a result, a pressure difference is generated between the pressure from the outside of the diaphragm 42 and the air pressure in the sealed cavity. The pressure difference causes the diaphragm 42 to deform and produce relative displacement, thereby changing the cavity length of the sealed cavity along the second direction D2. Furthermore, the change in the cavity length will cause a change in the feedback light signal, and the pressure change in the battery cell 10 can be analyzed by demodulating the feedback light signal.

[0086] Furthermore, the first end 51 of the optical fiber 5 (i.e., the end opposite to the sensing unit 4) receives the feedback optical signal reflected by the diaphragm 42. The feedback optical signal carries the deformation information of the diaphragm 42, that is, the change information of the gas pressure inside the battery cell 10. By analyzing the change of the feedback optical signal through demodulation and other means, the pressure state inside the battery cell 10 can be inferred, thereby realizing real-time monitoring of the safety of the corresponding battery cell 10.

[0087] Furthermore, a high reflectivity film 43 is attached to the surface of the diaphragm 42 facing the base 41. The high reflectivity film 43 can enhance the reflection efficiency of the diaphragm 42 to the test light signal. When the test light signal emitted by the optical fiber 5 is irradiated onto the diaphragm 42, due to the presence of the high reflectivity film 43, most of the light signal will be reflected to form a feedback light signal received by the first end 51 of the optical fiber 5. This efficient reflection mechanism ensures that the loss of the light signal during the transmission process is minimized, thereby improving the sensitivity and accuracy of the sensor 300 for monitoring the pressure and / or temperature of the battery cell 10.

[0088] In some embodiments, the high reflectivity film 43 may be a dielectric film or a metal film, such as gold or silver. When the test light signal is directed to the high reflectivity film 43, most of the test light signal may be reflected back by specular reflection, for example, achieving a reflectivity of 99%.

[0089] Further reference Figure 8 The base 41 may include: a plate portion 411 made of glass; a first ring portion 412 supported between the plate portion 411 and the diaphragm 42, and the plate portion 411, the first ring portion 412 and the diaphragm 42 together form the sealed cavity.

[0090] Specifically, the plate portion 411 made of glass material has excellent transparency. Therefore, it can ensure that the test light signal maintains low loss and distortion when passing through. Furthermore, the plate portion 411 made of glass material also has high chemical stability and thermal stability, and can maintain stable performance in the harsh environment inside the battery.

[0091] Furthermore, the diaphragm 42 can be connected to the first ring portion 412 at one end of the first ring portion 412 away from the plate portion 411. With the support of the first ring portion 412, the plate portion 411, the first ring portion 412 and the diaphragm 42 form the sealing cavity.

[0092] Furthermore, a semi-transparent and semi-reflective film 44 is attached to the surface of the plate portion 411 facing the membrane 42 . The plate portion 411 is suitable for forming a resonant cavity, and the feedback optical signal passing through the resonant cavity carries the temperature information of the battery cell 10 .

[0093] In some embodiments, the semi-transparent and semi-reflective film 44 may be, for example, a dielectric film. When the test light signal is directed toward the semi-transparent and semi-reflective film 44, a portion of the light signal is transmitted into the sealed cavity, and another portion of the light signal is reflected back to the first end 51 of the optical fiber 5 through the mirror surface. For example, 50% of the test light signal is transmitted into the sealed cavity, and 50% of the test light signal is reflected back to the first end 51 of the optical fiber 5.

[0094] Furthermore, a resonant cavity (also referred to as an "interference cavity") is formed between the two surfaces of the plate portion 411 along the second direction D2. According to the principle of thermal expansion and contraction, when the temperature of the gas inside the first through hole 31 changes, the cavity length of the resonant cavity will also change along the second direction D2. By analyzing the feedback light signal generated by the partial test light signal reflected back by the semi-transparent and semi-reflective film 44, the temperature inside the first through hole 31 (that is, inside the battery cell 10) can be monitored.

[0095] In some embodiments, the resonant cavity formed by the plate portion 411 may also be used for temperature compensation of pressure information to improve the accuracy of monitoring.

[0096] From the above, the sensing unit 4 adopts an optical-mechanical structure of a silicon-based double interference cavity. By respectively detecting the change in the FSR (Free Spectral Range) of the two interference cavities (between the diaphragm 42 and the plate 411, and between the two surfaces of 411 along the second direction D2) in the frequency domain, that is, the change in the peak-to-peak distance, the pressure value and temperature value inside the battery cell can be calculated.

[0097] In a typical application scenario, when the first end 51 of the optical fiber 5 emits a test light signal, the test light signal will first pass through the plate portion 411 and be emitted toward the semi-transparent and semi-reflective membrane 44. After passing through the semi-transparent and semi-reflective membrane 44, a portion of the test light signal is directly reflected back to the resonant cavity formed by the plate portion 411, and is finally received by the first end of the optical fiber 5. The feedback light signal formed by the portion of the test light signal reflected by the semi-transparent and semi-reflective membrane 44 carries the temperature information of the battery cell 10.

[0098] Furthermore, part of the test light signal that passes through the semi-transparent and semi-reflective film 44 can enter the sealed cavity and irradiate the diaphragm 42 (for example, the high reflectivity film 43 attached to the diaphragm 42). When the test light signal enters the sealed cavity, a comb-shaped light spectrum will be generated between the high reflectivity film 43 and the semi-transparent and semi-reflective film 44. When the center distance (that is, the cavity length of the sealed cavity along the second direction D2) changes, the comb-shaped light spectrum will also change accordingly. Furthermore, according to the deformation of the diaphragm 42 (caused by the change in gas pressure inside the battery cell 10), the test light signal will be reflected to form a feedback light signal carrying the internal pressure information of the battery cell 5.

[0099] Furthermore, the sensing part 4 may further include: a second ring part 45, the second ring part 45 is arranged on the side of the diaphragm 42 away from the first ring part 412, and the diaphragm 42 is clamped between the first ring part 412 and the second ring part 45. Thus, through the clamping of the first ring part 412 and the second ring part 45, the diaphragm 42 can be stably accommodated in the first through hole 31 to achieve real-time monitoring of the safety of the battery cell.

[0100] In some embodiments, the first ring portion 412 , the second ring portion 45 , and the diaphragm 42 may all be made of silicon.

[0101] In some embodiments, the first ring portion 412 , the second ring portion 45 , and the diaphragm 42 may be integrally formed by an etching process or the like, and then connected to the plate portion 411 by a bonding process or the like.

[0102] Furthermore, the thickness of the wall of the second ring portion 45 close to the diaphragm 42 is greater than the thickness of the wall of the second ring portion 45 away from the diaphragm 42. In other words, the inner surface of the second ring portion 45 has a certain slope. Thus, the gas or liquid flowing through the sensing portion 4 can be introduced and relatively statically stay at the diaphragm 42, so that the diaphragm 42 is uniformly deformed.

[0103] Further reference Figures 3 to 6 The connecting portion 3 includes: a connecting column 33, the first through hole 31 and the second through hole 32 are formed on the connecting column 33, and the end of the connecting column 33 away from the first surface 101 is in contact with the cover 2; a connecting plate 34 connected to the outer peripheral surface of the connecting column 33, and the connecting plate 34 is in contact with and fixed to the first surface 101.

[0104] Specifically, the connecting column 33 is located inside the accommodating cavity 21, and along the first direction D1, the two ends of the connecting column 33 are directly or indirectly connected to the first surface 101 and the surface of the cover 2 facing the first surface 101. Further, the first through hole 31 is opened in the connecting column 33, which is used to connect the first opening 1 and the second opening 22, so that when the battery cell 10 fails (for example, overheating or overcharging causes internal gas expansion), the gas inside the battery cell 10 can flow from the first through hole 31 to the expansion valve 6, and when the pressure inside the battery cell 10 exceeds a preset threshold, the expansion valve 6 is pushed open for exhaust to avoid accidents such as explosion.

[0105] Furthermore, the second through hole 22 is opened in the connecting column 33, and communicates the outside of the connecting column 33 and the first through hole 1 inside. The second through hole 22 can be used to form a channel for transmitting and receiving the test optical signal and the feedback optical signal.

[0106] Furthermore, a through hole matching the outer diameter of the connecting column 33 is formed on the connecting plate 34 to facilitate the connection between the connecting column 33 and the connecting plate 34 .

[0107] In some embodiments, the connecting column 33 and the connecting plate 34 may also be integrally formed.

[0108] Furthermore, the connecting plate 34 can increase the contact area between the connecting portion 3 and the battery cell 10 (particularly the first surface 101), thereby improving the stability and strength of the connection. In addition, the connecting plate 34 may also be used to disperse stress to prevent the connection between components from loosening or being damaged due to vibration or impact during the use of the battery cell 10.

[0109] In some embodiments, the connecting plate 34 and the first surface 101 may be connected via a fixing member 104 .

[0110] In some embodiments, the area of ​​the connecting plate 34 is smaller than the area enclosed by the end surface of the cover 2 facing the first surface 101, that is, the cover 2 completely covers the connecting plate 34, and the connecting plate 34 is also located in the accommodating cavity 21. In this scenario, the connecting plate 34 and the cover 2 are fixedly connected to the battery cell 10 (the first surface 101) through the fixing members 104 respectively.

[0111] In some embodiments, the area of ​​the connecting plate 34 may also be equal to the area enclosed by the end surface of the cover 2 facing the first surface 101. In the scenario, the cover 2, the connecting plate 34 and the first surface 101 may be connected simultaneously by the fixing member 104. Thus, in actual production operations, the number of holes punched on the first surface 101 can be reduced, and the overall structural strength can be improved.

[0112] In some embodiments, the cover portion 2 is connected to the first surface 101 via the connecting plate 34 , and the accommodating cavity 21 is surrounded by the cover portion 2 and the connecting plate 34 .

[0113] In some embodiments, along a plane perpendicular to the first direction D1, the cross-sectional area of ​​the first through hole 31 is smaller than the opening area of ​​the first opening 1, and the connecting plate 34 closes the portion of the first opening 1 that exceeds the first through hole 31. The shape and area of ​​the first opening 1 may be consistent with the explosion-proof valve 6, for example. Thus, manufacturers may determine whether to produce a battery cell 10 including a sensor 300 or a battery cell 10 only provided with an explosion-proof valve 6 according to actual needs. In other words, the battery cell 10 with a sensor 300 provided in an embodiment of the present invention does not change the structure of the traditional battery cell 10, and there is no need to make a special design for the battery cell 10 in the production process, which can provide manufacturers and users with more choices.

[0114] Furthermore, the cross-sectional area of ​​the first through hole 31 is smaller than the opening area of ​​the first opening 1 , so that the gas inside the battery cell 10 can be concentrated inside the first through hole 31 , thereby improving the sensitivity and accuracy of the sensing unit 4 .

[0115] Furthermore, the battery cell 10 further includes a sealing structure 103 disposed between the connecting plate 34 and the first surface 101 .

[0116] In some embodiments, the sealing structure 103 is also disposed between the connecting column 33 and the cover 2. Thus, the sealing structure 103 can effectively improve the airtightness of the battery cell 10 as a whole, and prevent the gas or liquid inside the battery cell 10 from leaking into the external environment through the gap between the connecting portion 3 and the first surface 101 or the cover 2. In addition, the sealing structure 103 can also prevent external substances (such as air, moisture, dust, etc.) from invading the battery cell 10 and affecting the service life of the battery cell 10.

[0117] Further, combined with Figures 3 to 6 The battery cell 10 may further include: a connector 8 having a third end 81 and a fourth end 82 opposite to each other, wherein the third end 81 is used to receive the second end 52 of the optical fiber 5; a coupler 9 having a fifth end 91 and a sixth end 92 opposite to each other, wherein the fifth end 91 is coupled to the fourth end 82, and the sixth end 92 is suitable for pluggable connection with an optoelectronic device. Thus, through the connector 8 and the coupler 9, it is easier for the optical fiber 5 to transmit optical signals (including receiving test optical signals and sending feedback optical signals) to the outside of the battery cell 10.

[0118] In some embodiments, the connector 8 can be selected from: a circular threaded connector (FerruleContactor, FC), a Lucent Connector (Lucent Connector, LC), a snap-on circular interface connector (Stab & Twist, ST), a square connector (Square Connector, SC), etc.

[0119] In a preferred embodiment, the connector 8 may be an E2000 optical connector to enhance the convenience of plugging the connector 8 and the coupler 9 .

[0120] Furthermore, the coupler 9 is used to optically and mechanically align, dock and couple the external optical fiber plug of the battery core 10 and the internal plug-in connector 8. The coupler 9 can be an optical flange, and the model of the optical flange can be consistent with or compatible with the model of the connector as the plug-in connector 8. For example, the coupler 9 can use an optical flange that is compatible with the E2000 optical plug.

[0121] Furthermore, the sixth end 92 of the coupler 9 is also provided with an optical structure for plugging with the optical plug of the external optoelectronic device. Thus, through the plug-in connection, the external optoelectronic device can more conveniently realize the optical coupling with the battery cell 10 (especially the sensing unit 4), thereby realizing the bidirectional transmission of the test optical signal and the feedback optical signal between the battery cell 10 and the optoelectronic device. This pluggable connection method not only facilitates the installation and maintenance of the battery cell and the external optoelectronic device, but also improves the scalability of the battery cell 10.

[0122] In some embodiments, in combination Figure 6 and Figure 7 The fifth end 91 is accommodated in the accommodating cavity 21 , and a third opening 23 is formed on the side wall of the cover portion 2 , and the third opening 23 is used to expose the sixth end 92 .

[0123] Specifically, the cover 2 further includes a connecting plate 24, which is disposed in the accommodating cavity 21 and connects a pair of opposite side walls of the cover 2. The connecting plate 24 may be parallel to the first direction.

[0124] Furthermore, the connecting plate 24 is provided with an assembly hole 25. Through the assembly hole 25, the coupler 9 can be snap-fitted with the connecting plate 24. Thus, the coupler 9 can be stably accommodated in the accommodating cavity 21, and the shaking of the coupler 9 can be prevented from affecting the optical coupling effect between the plug connector 8 and the external optoelectronic device.

[0125] Further, after at least a portion of the coupler 9 passes through the assembly hole 25, the sixth end 92 of the coupler 9 is connected to the wall of the cover 2 forming the third opening 23. Thus, the sixth end 92 of the coupler 9 can be coupled to an external optoelectronic device through the third opening 23.

[0126] As described above, by using the battery 100 described in the present application, the temperature and pressure changes inside each battery cell 10 can be independently and accurately monitored or spot-checked through real-time monitoring or spot-checking of the temperature and pressure of the gas in the first through hole 31, thereby improving the safety of the entire battery 100. Even if a problem occurs in a battery cell 1, it can be quickly located and corresponding measures can be taken to avoid affecting the performance of the entire battery 100 battery pack.

[0127] Furthermore, the technical solution of the present invention does not require changing the original structure of the battery cell 10. It only requires adding a cover portion 2, a connecting portion 3, a sensing portion 4 and an optical fiber 5 between the original battery cell 10 and the explosion-proof valve 6. While not affecting the explosion-proof performance of the explosion-proof valve 6, it can also achieve effective monitoring of the working status of the battery cell 2, and has wide applicability and high reliability.

[0128] Furthermore, the present invention still retains the design of the explosion-proof valve 6, which can be movably covered on the side of the second opening 22 away from the first opening 1. The explosion-proof valve 6 can be used as a last resort to prevent the battery cell 10 from exploding, and the explosion-proof airway of the explosion-proof valve 6 reuses the first through hole 31. Therefore, while not affecting the explosion-proof performance, this solution can also achieve reliable monitoring of the safe operation of the battery cell 10.

[0129] Combination Figure 1 and Fig. 9 To solve the technical problems of the prior art, the present invention also provides a battery system 200, including: Figures 1 to 8A battery 100; a transmitting module 201, respectively optically coupled with the optical fiber 5 of each battery cell 10 in the battery 100, the transmitting module 201 is used to transmit a test optical signal to the optical fiber 5; a signal processing module 202, respectively optically coupled with the optical fiber 5 of each battery cell 10 in the battery 100, the signal processing module 202 is used to receive a feedback optical signal output by the optical fiber 5, and obtain a detection result according to the feedback optical signal, the detection result including temperature data and / or pressure data of the battery cell 10.

[0130] In some embodiments, the transmitting module 201 and the signal processing module 202 may be integrated into an optoelectronic device 203. The optoelectronic device 203 may be, for example, a silicon photonic sensor IMC analyzer (IMC, In-Memory Computing, also known as in-memory computing).

[0131] refer to Figure 1 , a socket 1005 may be provided on the housing 1001 of the battery 100. The socket 1005 may, for example, be an MPO (Multi-Fiber Push-On) socket. Through the socket 1005, the topological optical cable 1003 inside the battery 100 and the multi-core optical cable 1006 outside the battery 100 may be optically coupled. Among them, the number of cable cores in the topological optical cable 1003 and the multi-core optical cable 1006 is consistent with the number of battery cells 10 in the battery 100. For example, in an application scenario in which the battery 100 includes 16 battery cells 10, the number of cable cores in the topological optical cable 1003 and the multi-core optical cable 1006 is also 16.

[0132] Furthermore, inside the battery 100 , one end of the topological optical cable 1003 is an integrated plug 1004 , and the other end is scattered optical fibers, which are respectively connected to the corresponding battery cells 10 , so the topological optical cable 1003 is laid in a tree-like manner along the center line of the battery 100 .

[0133] Furthermore, one end of each scattered optical fiber in the topological optical cable 1003 that is away from the plug 1004 is an optical connector for plugging into the coupler 9 installed on the corresponding electric core 10. The optical connector can be, for example, an E2000 optical fiber plug.

[0134] In some embodiments, both ends of the multi-core optical cable 1006 may be connected to a plug 1004 , which are connected to the socket 1005 of the battery 100 and the optoelectronic device 203 , respectively.

[0135] Furthermore, the optoelectronic device 203 may also be equipped with a socket 2031 that matches the model of the plug 1004 .

[0136] refer to Fig. 9The battery system 200 may include a plurality of batteries 100. The plurality of batteries 100 are accommodated in the cabinet 400 and are respectively coupled to the optoelectronic device 203 to receive the test optical signal and send the feedback optical signal.

[0137] Furthermore, taking the silicon photonic sensor IMC analyzer as the optoelectronic device 203 as an example, the silicon photonic sensor IMC analyzer detects each battery 100 in the cabinet 400 one by one through its own internal detection rules, such as wavelength division multiplexing and time division multiplexing, so as to monitor the pressure value and temperature value of each battery cell 10 in each battery 100. Combined with the big data algorithm embedded in the silicon photonic sensor IMC analyzer, the health status of each battery cell 10 can be accurately identified, and true "battery cell level" management can be achieved.

[0138] In addition, under big data analysis, if it is found that one or some cells 10 in one or some batteries 100 in the cabinet 400 are in abnormal state, the cells 10 in the corresponding position can be easily replaced. The replacement process can be, for example, unplugging the optical connector (e.g., E2000 optical connector) in the coupler 9 of the abnormal cell 10, pulling out the abnormal cell 10, inserting a normal cell 10 in the empty position, and finally reinserting the optical connector into the coupler 9 of the newly inserted cell 10, thereby completing the replacement of the cell 10.

[0139] In order to solve the technical problems of the prior art, combined with Figures 1 to 8 The embodiment of the present invention further provides a sensor 300 for detecting the temperature and / or pressure of a battery cell 10 of a battery 100. The battery cell 10 is provided with a first opening 1 opening toward a first direction D1. The sensor 300 includes:

[0140] A cover 2 is detachably disposed on the outer surface of the battery cell 10 and covers at least the first opening 1. A second opening 22 is formed on the surface of the cover 2 facing the first direction D1. A receiving cavity 21 is formed inside the cover 2.

[0141] A connecting portion 3, at least a portion of which is accommodated in the accommodating cavity 21, the connecting portion 3 is provided with a first through hole 31 extending along the first direction D1, the first through hole 31 is connected to the first opening 1 and the second opening 22, the connecting portion 3 is provided with a second through hole 32 extending along the second direction D2, the second through hole 32 is connected to the first through hole 31, wherein the second direction D2 is perpendicular to the first direction D1;

[0142] The sensing portion 4 is attached to the wall of the connecting portion 3 forming the first through hole 31, and the projection of the second through hole 32 along the second direction D2 falls into the area surrounded by the sensing portion 4;

[0143] The optical fiber 5 has a first end 51 and a second end 52 relative to each other along the extension direction, wherein the first end 51 is accommodated in the second through hole 32 to transmit a test light signal to the sensing part 4 and receive a feedback light signal, wherein the feedback light signal is used to characterize the pressure and / or temperature of the battery cell 10.

[0144] The coordination and working principle of the components in the sensor 300 (including the cover 2, the connecting part 3, the sensing part 4, and the optical fiber 5) can be referred to in the above description. Figures 1 to 9 The description of the illustrated embodiment will not be repeated here.

[0145] In addition, the inventors also provide a demodulation algorithm idea for the temperature and pressure of the battery cell 10 when the MOMP chip is used as the sensing unit 4.

[0146] First, in elastic mechanics, when the central deformation of the diaphragm 42 is much smaller than the thickness of the diaphragm 42, the deformation at the central position of the diaphragm 42 is calculated based on the following formula:

[0147] Formula 1, ;

[0148] in, is the pressure acting on the diaphragm 42; is the effective radius of the pressure area to which the diaphragm 42 is subjected; is the Young's modulus of the material used for the diaphragm 42; is the thickness of the diaphragm 42; is the Poisson coefficient of the material used for the diaphragm 42; is the displacement of the center position of the diaphragm 42 under the pressure.

[0149] Formula 1 is transformed into:

[0150] Formula 2, .

[0151] Furthermore, in the optical FP resonant cavity, the comb spectrum of the optical frequency has the following formula:

[0152] Formula 3, ;

[0153] in, It is used to characterize the distance between two adjacent peaks in the frequency domain. When the FP cavity length remains unchanged, the "peak-to-peak distance" between any two adjacent peaks is equal, that is, is a constant; is the speed of light in a vacuum; is the refractive index coefficient of the FP cavity, in the vacuum cavity , in the air cavity ; is the cavity length of the FP cavity. For example, Figure 8 middle , is the cavity length in the initial state, that is, the cavity length of the resonant cavity when the diaphragm 42 is not subjected to pressure. In summary, Formula 3 becomes:

[0154] Formula 4, .

[0155] When the surface of the diaphragm 42 senses pressure, Formula 4 becomes:

[0156] Formula 5, ;

[0157] in, The cavity length becomes The frequency domain "peak-to-peak distance" when is the length of the cavity when the diaphragm 42 senses the external pressure. It can be seen that when the diaphragm 42 is subjected to the external pressure, the cavity length becomes shorter, that is, , obtained from formulas 4 and 5, . So we have:

[0158] Formula 6, ;

[0159] Among them, is the change in the length of the FP cavity, that is, the deformation of the pressure diaphragm.

[0160] Combining formula (2) and (7),

[0161] Formula 8, ,

[0162] Further, there are:

[0163] Formula 9, .

[0164] Finally, we have:

[0165] Formula 10, .

[0166] It can be seen from Formula 10 that as long as the change in the "peak-to-peak distance" in the frequency domain is measured and calculated, the pressure felt by the diaphragm 42 can be calculated.

[0167] If the temperature factor is taken into consideration, the parameter on the right side of Formula 10 can be changed into a function of temperature to compensate for the pressure value at the current temperature.

[0168] There is the following formula:

[0169] Formula 11, .

[0170] It should be understood that the term "and / or" herein is merely an association relationship describing associated objects, indicating that three relationships may exist, for example, A and / or B may represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " herein indicates that the associated objects before and after are in an "or" relationship. As used herein, unless otherwise expressly stated, the term "or" covers all possible combinations unless not feasible. For example, if a component is stated to include A or B, then unless otherwise expressly stated or not feasible, the component may include A, or B, or A and B. As a second example, if a component is stated to include A, B, or C, then unless otherwise expressly stated or not feasible, the component may include A, or B, or C, or A and B, or A and C, or B and C, or A and B and C.

[0171] The "plurality" appearing in the embodiments of the present application refers to two or more.

[0172] The relational terms appearing in the embodiments of the present application, such as first, second, etc., are only used to distinguish an entity or operation from another entity or operation, and do not require or imply any actual relationship or order between these entities or operations. In addition, the words "include", "have" and "comprise" and other similar forms are intended to be equivalent in meaning, and are open-ended, and one or more items behind any of these words are not meant to be an exhaustive list of such one or more items, or mean to be limited to one or more items listed. In the accompanying drawings and the specification, exemplary embodiments have been disclosed. However, many changes and modifications can be made to these embodiments. Therefore, although specific terms have been adopted, they are only used in a general and descriptive sense, not for the purpose of limitation.

[0173] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. A battery, characterized in that: The battery comprises at least one battery cell, wherein each of the battery cells has a first surface and a second surface opposite to each other along a first direction, and the battery cell comprises: A first opening, opened on the first surface and connected to the interior of the battery cell; a cover portion, which is disposed on the first surface and covers at least the first opening, wherein a receiving cavity is formed in the cover portion and a second opening is formed on a surface facing the first surface; A connecting portion, at least a portion of which is accommodated in the accommodating cavity, the connecting portion is provided with a first through hole extending along the first direction, the first through hole communicating with the first opening and the second opening, the connecting portion is provided with a second through hole extending along the second direction, the second through hole communicating with the first through hole, wherein the second direction is perpendicular to the first direction; a sensing portion, attached to a wall of the connecting portion forming the first through hole, wherein a projection of the second through hole along the second direction falls within an area surrounded by the sensing portion; An optical fiber, wherein along the extension direction, the optical fiber has a first end and a second end opposite to each other, wherein the first end is accommodated in the second through hole to transmit a test optical signal to the sensing portion and receive a feedback optical signal, wherein the feedback optical signal is used to characterize the pressure and / or temperature of the battery core; In response to the feedback optical signal used to characterize the pressure of the battery core, the sensing portion includes a base, which is attached to the connecting portion to form a wall of the first through hole; a diaphragm, which is arranged at an end of the base away from the optical fiber, and a sealed cavity is formed between the base and the diaphragm, and the diaphragm is suitable for generating corresponding deformation according to the pressure change of the gas in the first through hole, and the feedback optical signal carries the deformation information of the diaphragm; In response to the feedback light signal used to characterize the temperature of the battery cell, the sensing part includes a base, which is attached to the connecting part to form the wall of the first through hole, and the base includes a plate part, which is suitable for forming a resonant cavity. The feedback light signal passing through the resonant cavity carries the temperature information of the battery cell.

2. The battery according to claim 1, characterized in that Also includes: An explosion-proof valve is movably covered on a side of the second opening away from the first opening, and the explosion-proof valve can be pushed open by gas overflowing from the first through hole.

3. The battery according to claim 1, characterized in that Also includes: The ferrule is sleeved on the first end of the optical fiber and accommodated in the second through hole, and the outer surface of the ferrule is in contact with the inner wall of the second through hole.

4. The battery according to claim 1, characterized in that The surface of the film facing the base is covered with a high reflectivity film.

5. The battery according to claim 1, characterized in that The plate portion is made of glass, and the base further comprises: The first ring portion is supported between the plate portion and the diaphragm, and the plate portion, the first ring portion and the diaphragm together form the sealing cavity.

6. The battery according to claim 5, characterized in that A semi-transparent and semi-reflective film is attached to the surface of the plate portion facing the membrane.

7. The battery according to claim 5, characterized in that The sensing unit further includes: The second ring portion is arranged on a side of the diaphragm away from the first ring portion, and the diaphragm is clamped between the first ring portion and the second ring portion.

8. The battery according to claim 7, characterized in that The thickness of the wall of the second ring portion on a side close to the diaphragm is greater than the thickness of the wall of the second ring portion on a side away from the diaphragm.

9. The battery according to claim 1, characterized in that The connecting portion comprises: A connecting column, the first through hole and the second through hole are formed in the connecting column, and one end of the connecting column away from the first surface is in contact with the cover; A connecting plate is connected to the outer peripheral surface of the connecting column, and the connecting plate is attached to the first surface and fixed to the first surface.

10. The battery according to claim 9, characterized in that Along a plane perpendicular to the first direction, a cross-sectional area of ​​the first through hole is smaller than an opening area of ​​the first opening, and the connecting plate closes a portion of the first opening that exceeds the first through hole.

11. The battery according to claim 9, characterized in that The cover is connected to the first surface via the connecting plate, and the accommodating cavity is surrounded by the cover and the connecting plate.

12. The battery according to claim 9, characterized in that Also includes: A sealing structure is arranged between the connecting plate and the first surface, and / or between the connecting column and the cover.

13. The battery according to claim 1, characterized in that Also includes: A connector having a third end and a fourth end opposite to each other, wherein the third end is used to receive the second end of the optical fiber; The coupler has a fifth end and a sixth end opposite to each other, wherein the fifth end is coupled to the fourth end, and the sixth end is suitable for pluggable connection with an optoelectronic device.

14. The battery according to claim 13, characterized in that The fifth end is accommodated in the accommodating cavity, and a third opening is formed on the side wall of the cover portion, and the third opening is used to expose the sixth end.

15. A battery system, characterized in that: include: The battery according to any one of claims 1 to 14; A transmitting module, optically coupled to the optical fiber of each cell in the battery, and configured to transmit a test optical signal to the optical fiber; The signal processing module is optically coupled to the optical fiber of each battery cell in the battery, and is used to receive the feedback optical signal output by the optical fiber, and obtain a detection result according to the feedback optical signal, wherein the detection result includes the temperature data and / or pressure data of the battery cell.

16. A sensor for detecting temperature and / or pressure of a battery cell, wherein the battery cell is provided with a first opening opening toward a first direction, wherein: The sensor comprises: A cover portion is detachably disposed on the outer surface of the battery core and covers at least the first opening, a second opening is formed on the surface of the cover portion facing the first direction, and a receiving cavity is formed inside the cover portion; A connecting portion, at least a portion of which is accommodated in the accommodating cavity, the connecting portion is provided with a first through hole extending along the first direction, the first through hole communicating with the first opening and the second opening, the connecting portion is provided with a second through hole extending along the second direction, the second through hole communicating with the first through hole, wherein the second direction is perpendicular to the first direction; a sensing portion, attached to a wall of the connecting portion forming the first through hole, wherein a projection of the second through hole along the second direction falls within an area surrounded by the sensing portion; An optical fiber, wherein along the extension direction, the optical fiber has a first end and a second end opposite to each other, wherein the first end is accommodated in the second through hole to transmit a test optical signal to the sensing portion and receive a feedback optical signal, wherein the feedback optical signal is used to characterize the pressure and / or temperature of the battery core; In response to the feedback optical signal used to characterize the pressure of the battery core, the sensing portion includes a base, which is attached to the connecting portion to form a wall of the first through hole; a diaphragm, which is arranged at an end of the base away from the optical fiber, and a sealed cavity is formed between the base and the diaphragm, and the diaphragm is suitable for generating corresponding deformation according to the pressure change of the gas in the first through hole, and the feedback optical signal carries the deformation information of the diaphragm; In response to the feedback light signal used to characterize the temperature of the battery cell, the sensing part includes a base, which is attached to the connecting part to form the wall of the first through hole, and the base includes a plate part, which is suitable for forming a resonant cavity. The feedback light signal passing through the resonant cavity carries the temperature information of the battery cell.

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