Battery pack

Abstract

The utility model relates to the technical field of battery pack monitoring, and provides a battery pack, which is applied to the battery pack and comprises a shell, a plurality of battery cell stacks, a control unit and an illumination sensor. The shell comprises a top cover and a lower box body which are connected with each other, and the plurality of battery cell stacking bodies and the control unit are arranged on a bottom plate of the lower box body; the illumination sensor is arranged in the shell, and the illumination sensor is configured to be capable of detecting light intensity information of light beams and sending the light intensity information of the light beams to the control unit. Through the independent configuration scheme of the shell structure and the illumination sensor, the illumination sensor can judge the state of the battery pack through the light intensity change. Abnormity (such as short-circuit arc and local high-temperature light emission before thermal runaway) in the battery is recognized through light intensity fluctuation, and active safety protection is achieved. For example, after an abnormal optical signal is detected, the system can cut off the circuit within millisecond-level time, and safety accidents are avoided.

Description

Technical Field

[0001] This utility model relates to the field of battery pack monitoring technology, and in particular to a battery pack. Background Technology

[0002] With the rapid development of new energy vehicles and energy storage equipment, the safe operation of power battery packs, as the core energy carrier, has become a focus of industry attention. Under complex operating conditions, battery packs may experience various abnormal states due to physical damage, environmental corrosion, or internal faults. These mainly include: mechanical opening (such as unauthorized disassembly of the casing), liquid intrusion (such as short circuits caused by water immersion), and thermal runaway (such as chain reactions caused by thermal propagation of individual cells).

[0003] If these abnormal conditions are not identified and addressed in a timely manner, they can lead to serious safety incidents. Therefore, it is necessary to monitor the status of the battery pack in real time. Utility Model Content

[0004] In view of the shortcomings of the prior art described above, the purpose of this utility model is to propose a battery pack for detecting the status information of the battery pack.

[0005] To achieve the above and other related objectives, this utility model provides a battery pack, comprising:

[0006] A housing, the housing comprising a top cover and a lower housing connected to each other;

[0007] Multiple battery cell stacks and a control unit are both mounted on the bottom plate of the lower housing; and a light sensor is mounted inside the housing, the light sensor being configured to detect the light intensity information of a light beam and send the light intensity information of the light beam to the control unit.

[0008] In an optional embodiment of the present invention, a light source is further provided in the housing, and one of the light source and the light sensor is located on the bottom plate of the lower housing. The light source is configured such that the light beam emitted by the light source can be transmitted to the light sensor.

[0009] In an optional embodiment of the present invention, a light reflecting device is further provided inside the housing. The light reflecting device is disposed on the bottom plate of the lower housing and is configured such that it can reflect the light beam emitted by the light source to the light sensor.

[0010] In an optional embodiment of this invention, the position of the light sensor and the light source is higher than that of the light reflecting device.

[0011] In an optional embodiment of this utility model, multiple light reflecting devices are provided, and the multiple light reflecting devices are respectively placed in different areas of the bottom plate of the lower box.

[0012] In an optional embodiment of this utility model, the light source is an infrared light source.

[0013] In an optional embodiment of this utility model, the light sensor is configured to send light intensity information of the light beam to the control unit so that the control unit determines that when the light intensity decreases, it cuts off the power output of the battery pack.

[0014] In an optional embodiment of this utility model, the light sensor is integrated into the top cover, above the battery cell stack, or on the bottom plate of the lower housing.

[0015] In an optional embodiment of this utility model, the battery cell stack is disposed in the battery cell compartment of the lower housing, the control unit is disposed in the electrical compartment of the lower housing, the battery cell compartment and the electrical compartment are separated by a middle beam, and the light sensor is disposed on the middle beam.

[0016] In an optional embodiment of this utility model, at least three light sensors are provided, and the at least three light sensors are not located on the same straight line.

[0017] In an optional embodiment of this utility model, the three light sensors are configured to send light intensity information of the light beam to the control unit respectively, so that when the control unit determines that the light intensity detected by the three light sensors increases and the detected light intensities are different, it issues a thermal runaway alarm and / or cuts off the power output of the battery pack.

[0018] In an optional embodiment of the present invention, the control unit is configured to: when the battery pack experiences thermal runaway, receive light intensity information of the light beam sent by each of the light sensors, so as to determine the location of thermal runaway based on the position of each light sensor and the detected light intensity.

[0019] The technical advantage of this invention lies in the independent configuration of the housing structure and the light sensor, allowing the light sensor to determine the battery pack's status through changes in light intensity. By identifying internal battery anomalies (such as short-circuit arcs or localized high-temperature luminescence before thermal runaway) through light intensity fluctuations, proactive safety protection is achieved. For example, upon detecting an abnormal light signal, the system can cut off the circuit within milliseconds, preventing safety accidents. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the battery pack structure in one embodiment of the present invention;

[0022] Figure 2 This is a simplified diagram showing the location of the light sensor in the battery pack according to one embodiment of the present invention;

[0023] Figure 3 This is a simplified diagram showing the position of the light sensor and light source of the battery pack in one embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram of the operation of the light sensor, light source and light reflection device of the battery pack in one embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram of the light beam reflection inside the battery pack as water is entering one embodiment of the present invention;

[0026] Figure 6 This is a schematic diagram of the light beam reflection of the water-submerged light reflection device in one embodiment of the present invention.

[0027] Explanation of reference numerals in the attached drawings: 10, top cover; 20, lower housing; 21, bottom plate; 30, battery cell stack; 40, light sensor; 50, light source; 60, light reflection device; 70, control unit. Detailed Implementation

[0028] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. It should be noted that, unless otherwise specified, the following embodiments and features described therein can be combined with each other.

[0029] It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0030] With the rapid development of new energy vehicles and the energy storage industry, the safety of power battery packs, as the core energy carrier, is directly related to the reliability of vehicle operation and the safety of users. Under complex operating conditions, battery packs may experience the following three typical abnormal states due to physical damage, environmental corrosion, or internal faults, requiring real-time detection and rapid response:

[0031] Unauthorized opening refers to a situation where the battery pack casing (top cover 10 and lower casing 20) is illegally opened, commonly seen in non-professional repair or malicious damage scenarios. Such operations may expose high-voltage components, posing a risk of electric shock, or damage the internal sealing structure, causing secondary damage.

[0032] Liquid intrusion (IP protection failure) occurs when liquids (such as rainwater or condensate) seep into the battery pack due to aging seals, impact damage, or water exposure. Liquid intrusion can lead to decreased insulation performance, corrosion of metal components, and even short circuits and fires.

[0033] Thermal runaway is a chain reaction of exothermic reactions triggered by short circuits, overcharging, or mechanical abuse within the battery cell, manifested as a sudden temperature rise, smoke release, and gas ejection. The spread of thermal runaway is extremely rapid.

[0034] Therefore, it is necessary to develop an integrated and highly reliable detection system to achieve collaborative protection by instantly blocking unauthorized opening, accurately identifying liquid intrusion, and locating thermal runaway early.

[0035] To achieve the above objectives and other related objectives, such as Figures 1-6 As shown, this utility model proposes a battery pack, including a housing, a stack of multiple battery cells 30, a control unit 70, and a light sensor 40. The light sensor 40 can specifically be a photodiode or a photoresistor.

[0036] The housing consists of a detachable top cover 10 and a lower housing 20.

[0037] like Figure 1 As shown, multiple battery cell stacks 30 and a control unit 70 are all mounted on the bottom plate of the lower housing 20. Specifically, the battery cell stack 30 is composed of multiple lithium-ion cells (such as ternary or lithium iron phosphate cells) connected in series or parallel and fixed inside the battery cell compartment of the lower housing 20.

[0038] The control unit 70 is specifically the battery management system (BMS) within the battery pack. The battery management system is integrated into the electrical compartment of the lower enclosure and is responsible for battery status monitoring, equalization management, and safety control.

[0039] like Figures 1-6As shown, the light sensor 40 is located inside the housing. When the top cover 10 is illegally opened, ambient light (natural light or artificial lighting) enters the housing, causing the light intensity detected by the light sensor 40 to rise instantaneously. The light sensor 40 is configured to detect the light intensity information of the light beam and send this information to the control unit 70. During this process, the sensor converts the light intensity signal into an electrical signal, which the battery management system receives and analyzes in real time.

[0040] The control unit 70 cuts off the power output of the battery pack when it detects an increase in light intensity. Specifically, when the light intensity exceeds a preset threshold, it is determined that the cover has been abnormally opened. The battery management system, upon detecting the opening signal, triggers a high-voltage relay (such as a contactor) to disconnect, causing the battery pack output voltage to drop to a safe range. The battery management system writes the timestamp of the opening event, the peak light intensity, and other data into its memory. The number of times the cover was opened, the time, and the light intensity data recorded by the battery management system can serve as valid electronic evidence in legal disputes. Combining the number of times the cover was opened (e.g., more than 3 times) with battery health (SOH) provides a quantitative basis for after-sales warranty (e.g., frequent opening may lead to a decrease in sealing, triggering warranty restrictions).

[0041] The above solution reduces the need for housing openings, improves the reliability of IP67 protection level, and reduces hardware costs. The same light sensor 40 can be reused for thermal runaway detection or water immersion detection, achieving "one device for multiple uses".

[0042] like Figures 3-6 As shown, it also includes a light source 50 disposed in the housing. In an optional embodiment of this invention, the light source 50 is an infrared light source (such as an 850nm wavelength LED). One of the light source 50 and the light sensor 40 is located on the bottom plate 21 of the lower housing 20. In the case of liquid intrusion, the bottom plate 21 is a place where water accumulates. When water accumulates on the bottom plate 21, the water will block the light sensor 40 or the light source 50.

[0043] like Figure 4 As shown, the light source 50 is assembled such that the light beam emitted by the light source 50 can be transmitted to the light sensor 40. A directional optical path is formed between the light source 50 and the light sensor 40. The light source 50 emits an infrared light beam, and the sensor receives the direct or reflected light signal. The infrared light beam is much more sensitive to liquid water than to condensed water vapor, and combined with a dynamic filtering algorithm, it can effectively distinguish between actual incoming water and ambient humidity fluctuations.

[0044] Water absorbs / scatters infrared light beams, causing a decrease in the light intensity received by the sensor. The battery management system monitors the light intensity in real time. If the detected value is below a preset threshold for a sustained period, it can be identified as a water ingress event. This triggers the following actions:

[0045] Disconnect the power output of the battery pack to prevent short circuits caused by water immersion;

[0046] Activate the drainage device (such as an optional miniature air pump);

[0047] Record the spatiotemporal data (time, location, light intensity curve) of the water ingress event and upload it to the cloud platform.

[0048] like Figure 4 As shown, it also includes a light-reflecting device 60 (such as a microprism array or aluminized PET film) disposed inside the housing, and the light-reflecting device 60 is disposed on the bottom plate 21 of the lower housing 20. Figure 4 As shown, the light reflecting device 60 is configured to reflect the light beam emitted by the light source 50 to the light sensor 40. This ensures that the light beam emitted by the light source 50 is accurately transmitted to the light sensor 40 after reflection.

[0049] The light source 50 and the light sensor 40 are located at different positions on the housing (e.g., the light source 50 is at the edge of the bottom plate 21, and the sensor is inside the top cover 10), forming a closed light path through the light reflection device 60. Under normal circumstances, such as... Figure 4 As shown, the intensity of the reflected light received by the light sensor 40 remains stable. Figure 4 The solid line in the middle indicates the direction of the beam. For example... Figure 5 As shown, when the water depth on the bottom plate 21 is shallow and it is not covered by the light reflector 60, the light sensor 40 normally receives the reflected light. Figure 6 As shown, when the water depth on the base plate 21 exceeds a certain range, the water covers the light reflector 60, causing total internal reflection failure or enhanced light absorption in the optical path, resulting in a significant decrease in the light intensity received by the sensor 40. The battery management system monitors the rate of change of light intensity in real time. If the light intensity decreases beyond a threshold and persists for a period of time, it is determined to be a water ingress event. After determining water ingress, the battery management system disconnects the high-voltage contactor, reducing the battery pack output voltage to a safe voltage.

[0050] In an optional embodiment of this utility model, multiple light reflection devices 60 are provided, and multiple independent detection areas are divided on the bottom plate 21 of the lower housing 20. The multiple light reflection devices 60 are placed in different areas of the bottom plate 21 of the lower housing 20. The light reflection device 60 and the corresponding light source 50-sensor pair form an independent optical path. Through the cross coverage of multiple optical paths, it is ensured that there are no blind spots in the detection of the entire area of ​​the bottom plate 21. Even if there is local water accumulation or the light reflection device 60 fails, the water ingress status can still be determined by the redundancy of adjacent optical paths. The battery management system sets an independent light intensity baseline for each light reflection device 60 (e.g., a baseline value of 800 Lux for area 1 and a baseline value of 820 Lux for area 2), and dynamically adjusts for environmental interference (e.g., reflectivity attenuation caused by dust deposition). Based on the location of the failed light reflection device 60 (e.g., the light intensity in areas 3 and 4 is zero), the leakage point (e.g., sealant joints or cooling pipe interfaces) can be quickly located, improving maintenance efficiency. By comparing light intensity data from multiple regions, the system can distinguish between real water ingress (synchronous light intensity decrease in multiple regions) and local interference (such as contamination of reflective film in a single region), thus reducing the false alarm rate.

[0051] like Figures 4-6 As shown, the light sensor 40 and the light source 50 are positioned higher than the light reflector 60. Mounting the light source 50 and light sensor 40 at a higher position inside the battery pack housing reduces physical obstruction of the optical path by the cell stack 30, wiring harnesses, etc., ensuring the integrity of the optical path. The light reflector 60 is fixed to the bottom plate 21 of the lower housing 20. The optical path is: light source 50 → light reflector 60 → sensor, forming a top-down reflection detection channel. This high-positioning avoids direct contact between the sensor and light source 50 and water accumulation on the bottom plate 21, improving the durability of key optical components. When water covers the light reflector 60, total internal reflection failure or enhanced scattering occurs in the optical path, causing a sudden drop in the light intensity received by the sensor and triggering a water ingress alarm.

[0052] In an optional embodiment of this utility model, the light sensor 40 is integrated into the top cover 10. The sensor directly monitors the light intensity change at the joint between the top cover 10 and the lower housing 20. When the cover is abnormally opened, external light enters, causing the light intensity to rise instantaneously. This, combined with the light reflection device 60, forms a vertical light path, which can simultaneously detect water accumulation or sealing failure.

[0053] In an optional embodiment of this invention, the light sensor 40 is integrated above the cell stack 30. The light sensor 40 is embedded in a bracket or module cover plate on top of the cell stack 30, and faces the cell surface horizontally or at an angle.

[0054] In an optional embodiment of this utility model, the light sensor 40 is integrated on the bottom plate 21 of the lower housing 20. The light sensor 40 is directly embedded in the surface of the bottom plate 21 of the lower housing 20 or near the drainage channel, forming a vertical / tilted light path with the light reflecting device 60 (such as a microprism array) or the light source 50.

[0055] In an optional embodiment of this utility model, the battery cell stack 30 is disposed in the battery cell compartment of the lower housing 20, and the control unit 70 is disposed in the electrical compartment of the lower housing 20. The battery cell compartment and the electrical compartment are separated by a middle beam. The lower housing 20 is divided into the battery cell compartment and the electrical compartment by the middle beam to achieve physical isolation and reduce the risk of electromagnetic interference and heat conduction.

[0056] The light sensor 40 is mounted on the intermediate beam. The intermediate beam serves as a structural support and also as a carrier for the optical detection channel. The light sensor 40 is embedded inside or on the surface of the intermediate beam (e.g., through slotted encapsulation), forming a cross-regional monitoring node.

[0057] In the early stages of thermal runaway, an internal short circuit within the battery cell triggers intense heat release (temperatures can reach 500-800℃), accompanied by electrolyte decomposition and separator rupture, generating a large amount of visible light and near-infrared radiation. This causes a sudden increase in the light intensity received by the light sensor 40, which can then determine whether the battery has experienced thermal runaway.

[0058] In an optional embodiment of this invention, at least three light sensors 40 are provided, and these three light sensors 40 are not located on the same straight line. The three light sensors 40 are distributed in a non-collinear manner (such as an equilateral triangle or L-shaped layout), covering the core area of ​​the battery pack (such as above the cell stack 30, the middle beam, and the bottom plate 21 of the lower housing 20), forming a three-dimensional detection network. The sensors receive direct or reflected light from the light source 50 (such as an infrared light source), ensuring full coverage without blind spots.

[0059] In an optional embodiment of this utility model, the three light sensors 40 are configured to send light intensity information of the light beam to the control unit 70 respectively, so that when the control unit 70 determines that the light intensity detected by the three light sensors 40 increases and the detected light intensities are different, it issues a thermal runaway alarm and / or cuts off the power output of the battery pack.

[0060] The difference between thermal runaway from open flame and natural light is:

[0061] The main radiation bands of thermal runaway open flames are: visible light (400-700nm) + near-infrared (800-1500nm), accompanied by specific wavelength peaks generated by electrolyte combustion (such as the CO radiation peak at 4300nm); the spectral range is wide and the intensity increases abruptly. Furthermore, the light intensities detected by the three light sensors are different.

[0062] Natural solar light has a continuous spectrum with a main peak in the visible light range (550nm) and no specific wavelength spikes. Furthermore, when the battery pack was abnormally activated, the light intensity detected by the three light sensors 40 was approximately the same.

[0063] Therefore, when thermal runaway occurs, the visible light / infrared radiation emitted from the fault point attenuates with distance, resulting in significant differences in the light intensity received by each sensor, thus distinguishing between natural light and the open flame of thermal runaway. This allows for the determination of whether the situation is an abnormal start-up or a thermal runaway state.

[0064] In an optional embodiment of this invention, the control unit 70 is configured to: receive light intensity information from the light beams emitted by each light sensor 40 when thermal runaway occurs in the battery pack, so as to determine the location of the thermal runaway based on the position of each light sensor 40 and the detected light intensity. When thermal runaway occurs in the battery pack, since the three light sensors 40 receive different light intensities, the battery management system can determine the location of the thermal runaway cell.

[0065] Specifically, the location of thermal runaway can be determined by the intersection of three spheres with different centers. Assuming the thermal runaway point is located in three-dimensional space, and the three illumination sensors 40 are located at known positions, the light intensity received by each sensor can be converted into distance based on the inverse square law of light intensity attenuation. This yields three spherical equations, and the intersection of these three equations determines the location of the thermal runaway. The non-collinear layout ensures that the three spheres intersect at a single point, thus achieving precise positioning.

[0066] In the above solution, the light sensor 40 can simultaneously detect abnormal opening of the battery pack, water ingress into the battery pack, and thermal runaway of the battery cells, and determine the location of the thermal runaway. This enables the same sensor to be used for different functions, thereby reducing costs.

[0067] This invention reduces the overall failure rate of the system through non-contact optical detection and integrated design.

[0068] By combining the direction of sudden changes in light intensity (rising / falling) with spatial distribution, fault types can be accurately distinguished.

[0069] Increased light intensity → Opening of lid (intrusion of external light);

[0070] Decreased light intensity → water immersion or thermal runaway smoke (light path blockage or scattering);

[0071] Light intensity gradient distribution → thermal runaway localization (using the three-sphere intersection algorithm).

[0072] The battery management system triggers differentiated actions based on the fault type:

[0073] Open cover event → Cut off power output from battery pack (response within 20ms);

[0074] Flooding incident → Start drainage pump + insulation monitoring;

[0075] Thermal runaway → Locate and isolate the faulty module + activate the fire suppression system.

[0076] In summary, through the independent configuration of the housing structure and the light sensor 40, the light sensor 40 can determine the state of the battery pack by observing changes in light intensity. It identifies internal battery anomalies (such as short-circuit arcs or localized high-temperature luminescence before thermal runaway) by detecting light intensity fluctuations, thus achieving proactive safety protection. For example, upon detecting an abnormal light signal, the system can cut off the circuit within milliseconds to prevent accidents. The combined layout of the light sensor 40, light source 50, and light reflection device 60 enables simultaneous detection of the battery pack's open state, water ingress state, and thermal runaway state. Employing an infrared light source and closed-loop optical path design, it senses abnormal states in real time through changes in light intensity. This reduces the thermal runaway detection response time and eliminates the impact of electromagnetic interference, thus lowering the false alarm rate. Based on the spatial distribution of multiple sensors and light intensity difference analysis, the thermal runaway initiation cell module can be located, enabling fault localization. The sensor 40 is integrated into existing structures such as the top cover 10 and the middle beam, requiring no additional openings, ensuring compatibility with mainstream battery pack designs, and reducing modification costs.

[0077] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

[0078] Throughout this description, numerous specific details, such as examples of components and / or methods, are provided to provide a complete understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention may be practiced without one or more of these specific details or by other devices, systems, components, methods, parts, materials, components, etc. In other instances, well-known structures, materials, or operations have not been specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.

[0079] Throughout this specification, references to "an embodiment," "an embodiment," or "a specific embodiment" mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention, but not necessarily in all embodiments. Therefore, the various representations of the phrases "in one embodiment," "in an embodiment," or "in a specific embodiment" in different places throughout the specification do not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic of any specific embodiment of the present invention can be combined with one or more other embodiments in any suitable manner. It should be understood that other variations and modifications of the embodiments of the present invention described and illustrated herein may be based on the teachings herein and will be considered part of the spirit and scope of the present invention.

[0080] It should also be understood that one or more of the elements shown in the figures may be implemented in a more separate or more integrated manner, or may even be removed because they are inoperable in certain circumstances or provided because they may be useful for a particular application.

[0081] Furthermore, unless otherwise expressly stated, any arrows in the accompanying drawings should be considered illustrative only and not limiting. Additionally, unless otherwise stated, the term "or" as used herein is generally intended to mean "and / or". Where a term is anticipated to provide a separation or combination capability that is unclear, a combination of components or steps will also be considered as indicated.

[0082] As used herein and throughout the claims below, unless otherwise specified, “a” and “the” include the plural references. Similarly, as used herein and throughout the claims below, unless otherwise specified, “in” means “in” and “on”.

[0083] The above description of the embodiments shown in this utility model (including the content set forth in the abstract of the specification) is not intended to be an exhaustive enumeration or to limit the utility model to the precise forms disclosed herein. Although specific embodiments and examples of the utility model have been described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the utility model, as will be recognized and understood by those skilled in the art. As indicated, these modifications can be made to the utility model in accordance with the above description of the embodiments described herein, and such modifications will be within the spirit and scope of the utility model.

[0084] This document has generally described the systems and methods in detail to aid in understanding the present invention. Furthermore, various specific details have been set forth to provide a general understanding of embodiments of the present invention. However, those skilled in the art will recognize that embodiments of the present invention can be practiced without one or more specific details, or using other devices, systems, accessories, methods, components, materials, parts, etc. In other instances, well-known structures, materials, and / or operations have not been specifically shown or described in detail to avoid obscuring aspects of embodiments of the present invention.

[0085] Therefore, although the present invention has been described herein with reference to specific embodiments thereof, freedom of modification, various changes and substitutions are also within the scope of the above disclosure, and it should be understood that in some cases, certain features of the present invention may be adopted without departing from the scope and spirit of the invention and without corresponding use of other features. Thus, many modifications can be made to adapt a particular environment or material to the essential scope and spirit of the present invention. The present invention is not intended to be limited to the specific terms used in the following claims and / or the specific embodiments disclosed as the best mode of carrying out the present invention, but the present invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Therefore, the scope of the present invention will be determined only by the appended claims.

Claims

1. A battery pack, characterized by, The application relates to a battery pack, comprising: a shell comprising a top cover (10) and a lower box body (20) connected to each other; a plurality of cell stacks (30) and a control unit (70) arranged on a bottom plate of the lower box body (20); and a light sensor (40) arranged in the interior of the shell, the light sensor (40) being configured to detect light intensity information of a light beam and send the light intensity information of the light beam to the control unit (70).

2. The battery pack of claim 1, wherein, The application further comprises a light source (50) arranged in the shell, one of the light source (50) and the light sensor (40) being arranged on the bottom plate (21) of the lower box body (20), the light source (50) being configured to transmit the light beam emitted by the light source (50) to the light sensor (40).

3. The battery pack of claim 2, wherein, The application further comprises a light reflection device (60) arranged in the interior of the shell, the light reflection device (60) being arranged on the bottom plate (21) of the lower box body (20), the light reflection device (60) being configured to reflect the light beam emitted by the light source (50) to the light sensor (40).

4. The battery pack of claim 3, wherein, The positions of the light sensor (40) and the light source (50) are higher than that of the light reflection device (60).

5. The battery pack of claim 3, wherein, The light reflection device (60) is arranged in multiple numbers, and the multiple light reflection devices (60) are arranged in different regions of the bottom plate (21) of the lower box body (20).

6. The battery pack of claim 2 or 3, wherein, The light source (50) is an infrared light source.

7. The battery pack of claim 2 or 3, wherein, The light sensor (40) is configured to send the light intensity information of the light beam to the control unit (70) to make the control unit (70) cut off the power output of the battery pack when the light intensity decreases.

8. The battery pack of claim 1, wherein, The light sensor (40) is integrally arranged in the top cover (10), above the cell stack (30) or on the bottom plate (21) of the lower box body (20).

9. The battery pack of claim 1, wherein, The cell stack (30) is arranged in a cell compartment of the lower box body (20), the control unit (70) is arranged in an electrical compartment of the lower box body (20), the cell compartment and the electrical compartment are separated by an intermediate beam, and the light sensor (40) is arranged on the intermediate beam.

10. The battery pack of claim 1, wherein, The light sensor (40) is arranged in at least three numbers, and the at least three light sensors (40) are not arranged on the same straight line.

11. The battery pack of claim 10, wherein, The three light sensors (40) are configured to send the light intensity information of the light beam to the control unit (70) respectively, so that the control unit (70) judges that the light intensity detected by the three light sensors (40) increases and the detected light intensity is different, and then sends a thermal runaway alarm and / or cuts off the power output of the battery pack.

12. The battery pack of claim 11, wherein, The control unit (70) is configured to receive the light intensity information of the light beam sent by each light sensor (40) when the battery pack is in thermal runaway, and determine the thermal runaway position according to the position and the detected light intensity of each light sensor (40).

Images