Claims:We Claim:
1. A battery thermal management system (100) to predict and prevent thermal runaway in energy storage device comprises:
a microprocessor (102);
an array of sensors (104) coupled to the microprocessor (102), wherein the array of sensors (104) comprises a plurality of type of sensors (104) to sense a plurality of gases, and wherein a plurality of each type of gases can be implemented at multiple locations within the energy storage pack;
a display unit (106) coupled to the microprocessor (102) to display data related to the array of sensors (104) in real time; and
for prevention of thermal runway when the temperature inside the energy storage device rises:
a battery management system (100) to shut off the energy storage device, and
a relay (108) coupled between the microprocessor (102) and a battery management system (100) of the energy storage device.
2. The battery thermal management system (100) as claimed in claim 1, a range of gas value, which is considered safe, is predefined.
3. The battery thermal management system (100) as claimed in claim 2, wherein the gas value is detected outside the predefined range of safe gas value, a battery management system (100) of the energy storage device is controlled and operated by the microprocessor (102) to shut down the energy storage device to prevent thermal runway.
4. The battery thermal management system (100) as claimed in claim 1, wherein Air Quality Monitoring sensor MQ135 can be used.
5. The battery thermal management system (100) as claimed in claim 1 comprises an exhaust fan outside the energy storage device to redirect the released gases at one location.

6. The battery thermal management system (100) as claimed in claim 1 comprises an alarm to indicate rise in level of gases indicative of thermal runway in the energy storage device.
7. A method for predicting and preventing thermal runaway in energy storage device by using a battery thermal management system (100), the system (100) comprises:
implementing a plurality of sensors (104) inside the battery thermal management system (100), wherein the plurality of sensors (104) includes multiple types of sensors (104) configured to sense multiple parameters;
displaying data related to the plurality of sensors (104) in real time on a display unit (106); and
if the plurality of sensors (104) indicate rise in temperature inside the energy storage device:
shutting off the energy storage device by controlling a battery management system (100),
switching off the energy storage device by controlling a relay (108) coupled between the microprocessor (102) and a battery management system (100) of the energy storage device.
8. The method as claimed in claim 8, comprises redirecting released gases at one location by using an exhaust fan implemented outside the energy storage device.
9. The method as claimed in claim 8, comprises indicating rise in level of gases indicative of thermal runway in the energy storage device by using an alarm.

Dated this on 23rd day of March, 2021

Agent for Applicant

Dr. Suryawanshi Mohini K.
(IN/PA-2023)
, Description:FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
[See section 10 and rule 13]

1. TITLE OF THE INVENTION
A BATTERY THERMAL MANAGEMENT SYSTEM

2. APPLICANT:

(a) Name : RANJANS LI-ON ENERGY PRIVATE LIMITED
(b) Nationality : An Indian registered company
(c) Address : Gat No. 1313, Near Dutt Mandir, Wadki, Pune Saswad Road,
Pune- 412308, Maharashtra, India.

THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.
TECHNICAL FIELD
[0001] The present invention relates to a battery thermal management device. More particularly, but not exclusively, to safety of battery pack. The present invention discloses a system for prediction and prevention of thermal runaway in Lithium Batteries by analyzing the various gases released inside the battery pack as the temperature inside the battery pack increases and using the temperature signals to shut down the battery to stop further increase in temperature and resultant thermal runaway.
BACKGROUND
[0002] Energy storage devices, such as battery packs, are tend to heat up while charging or discharging. The starting stage of thermal runway starts due to over charging, under charging or surrounding temperature. It could also be due to internal short circuits. Internal Short circuit with low resistance inside a battery pack leads to an extremely fast temperature rise, gas generation, cell swelling and ultimately battery rupture and failure. As the cell heats up the layer of solid electrolyte interface (SEI) starts to breakdown typically at temperature of 80`C.Once this layer of SEI breaks. It starts to react with electrolyte and Carbon anode and it leads to further increase in temperature of the cell. With further increase in the temperature of the electrolyte it starts to burn and emission of various gases more importantly CO2. Other hydrocarbon gases like Methane and Ethane are also released. To avoid such hazardous gas formation and emission, the battery management system has to be shut to prevent further increase in temperature.
[0003] Many solutions have been provided in the art to prevent over heating of the energy storage devices. One state-of-the-art discloses a system for monitoring parameters of an energy storage system having a multiplicity of individual energy storage cells. A radio frequency identification and sensor unit is connected to each of the individual energy storage cells. The radio frequency identification and sensor unit operate to sense the parameter of each individual energy storage cell and provides radio frequency transmission of the parameters of each individual energy storage cell. A management system monitors the radio frequency transmissions from the radio frequency identification and sensor units for monitoring the parameters of the energy storage system.
[0004] Another state of the art discloses a detection device for a combustion product of a lithium-ion battery, belonging to the technical field of chemical analysis. The detection device comprises a battery combustion box, a battery combustion stage, a gas sampling box, a plurality of real-time detection probes, a plurality of constant-value detection probes, a controller and the like, wherein the battery combustion stage is arranged in the battery combustion box, a lithium ion battery to be tested is put on the battery combustion stage, the lower part of the battery combustion stage is connected with a liquefied gas bottle through a fuel gas valve, the gas sampling box is connected with the battery combustion box through a sampling valve, the plurality of real-time detection probes are arranged in the battery combustion box, the plurality of constant-value detection probes are arranged in a constant voltage chamber, and the plurality of real-time detection probes and the plurality of constant-value detection probes are respectively connected with the controller. The detection device can focus on detection of toxic and harmful substances in the combustion product of the battery, and can be used for analyzing components of toxic and harmful substances in the combustion product of the battery, thus providing a theoretical foundation for design of lithium ion batteries of electric cars.
[0005] Yet another state of the art discloses a method for detecting an increased internal pressure in a lithium-ion cell by means of a membrane which is deformed under elevated internal pressure, wherein the membrane at a terminal connection pressure in the cell two electrical connections of the cell short circuits, so that a short-circuit current path between the terminals of the cell is formed, wherein the membrane upon deformation at a contact pressure in the cell without formation of the short-circuit current path is electrically connected to a contact element is produced, wherein the contact pressure is lower than the connection pressure and an increased internal pressure in the cell by means of the contact element is detected. Furthermore, the invention relates to a lithium-ion cell with electrical connections of the cell and a membrane, wherein by means of the membrane, when deformed at a contact pressure in the interior of the cell, an electrical connection with a contact element can be produced without passing the short-circuit current path, wherein the contact pressure is lower than the connection pressure, so that an increased internal pressure can be detected by means of the contact element .
[0006] Yet another state of the art discloses a battery management system with thermally integrated fire suppression includes a multiplicity of individual battery cells in a housing; a multiplicity of cooling passages in the housing within or between the multiplicity of individual battery cells; a multiplicity of sensors operably connected to the individual battery cells, the sensors adapted to detect a thermal runaway event related to one or more of the multiplicity of individual battery cells; and a management system adapted to inject coolant into at least one of the multiplicity of cooling passages upon the detection of the thermal runaway event by the any one of the multiplicity of sensors, so that the thermal runaway event is rapidly quenched.
[0007] Yet another state of the art discloses a system for detecting cell failure within a battery pack based on variations in the measured electrical isolation resistance of the battery pack is provided. The system includes an electrical isolation resistance monitoring subsystem for monitoring the electrical isolation resistance of the battery pack; a system controller coupled to the isolation resistance monitoring subsystem that detects when the electrical isolation resistance falls below a preset value; and a cell failure response subsystem that performs a preset response upon receipt of a control signal from the system controller, where the control signal is transmitted when the electrical isolation resistance falls below the preset value. The system may include a secondary effect monitoring system, wherein the cell failure response subsystem performs the preset response when the electrical isolation resistance falls below the preset value and the secondary effect is detected by the secondary effect monitoring system.
[0008] One conventional art discloses a strain gauge sensor system for monitoring changes in stain of a battery surface, said change in strain indicative of internal changes in the battery. The sensor system comprises a wire grid based sensor, the sensor electrically connected though for example a Wheatstone bridge to an RFID tag. In the presence of an RFID reader, the sensor system is activated, a signal representative of the resistance of the wire grid (and thus grid strain) transmitted to the reader, and the resistance value compared to resistance values for the healthy state of the battery.
[0009] Another conventional art discloses that Lithium Ion batteries include materials that provide advantageous endothermic functionalities contributing to the safety and stability of the batteries. The endothermic materials may include a ceramic matrix incorporating an inorganic gas-generating endothermic material. If the temperature of the lithium ion battery rises above a predetermined level, the endothermic materials serve to provide one or more functions to prevent and/or minimize the potential for thermal runaway, e.g., thermal insulation (particularly at high temperatures); (ii) energy absorption; (iii) venting of gases produced, in whole or in part, from endothermic reaction(s) associated with the endothermic materials, (iv) raising total pressure within the battery structure; (v) removal of absorbed heat from the battery system via venting of gases produced during the endothermic reaction(s) associated with the endothermic materials, and/or (vi) dilution of toxic gases (if present) and their safe expulsion from the battery system.
[0010] One state of the art discloses that thermal runaway in battery packs is suppressed by inserting packages of hydrated hydrogel at physical interfaces between groups of one or more cells. The hydrogel acts to diffuse and absorb thermal energy released by the cells in the event of a cell failure. During extreme overheating of a battery cell, the water stored by the hydrogel will undergo phase change, that is, begin to vaporize, thus absorbing large amounts of thermal energy and preventing thermal runaway.
[0011] Another state of the art discloses a system for detecting cell failure within a battery pack based on variations in the measured electrical isolation resistance of the battery pack is provided. The system includes an electrical isolation resistance monitoring subsystem for monitoring the electrical isolation resistance of the battery pack; a system controller coupled to the isolation resistance monitoring subsystem that detects when the electrical isolation resistance falls below a preset value; and a cell failure response subsystem that performs a preset response upon receipt of a control signal from the system controller, where the control signal is transmitted when the electrical isolation resistance falls below the preset value. The system may include a secondary effect monitoring system, wherein the cell failure response subsystem performs the preset response when the electrical isolation resistance falls below the preset value and the secondary effect is detected by the secondary effect monitoring system.
[0012] Another state of the art discloses a system and method for mitigating the effects of a thermal event within a non-metal-air battery pack is provided in which the hot gas and material generated during the event is directed into the metal-air cells of a metal-air battery pack. The metal-air cells provide a large thermal mass for absorbing at least a portion of the thermal energy generated during the event before it is released to the ambient environment. As a result, the risks to vehicle passengers, bystanders, first responders and property are limited.
[0013] Yet another state of the art discloses a battery pack thermal management system is provided that is comprised of at least one enclosure failure port integrated into at least one wall of a battery pack enclosure, where the enclosure failure port(s) remains closed during normal operation of the battery pack, and opens during a battery pack thermal runaway event, thereby providing a flow path for hot gas generated during the thermal runaway event to be exhausted out of the battery pack enclosure in a controlled fashion.
[0014] None of the state of the art and conventional art discloses simple yet effective and economic technical solution for detection of gases inside the battery pack and controlling the battery management system in the battery pack to shut down or using a relay to switch off the battery.

SUMMARY OF THE INVENTION
[0015] Over charging, under charging, or surrounding temperature of an energy storage device, referred hereinafter as to a battery pack, initiates burning of electrolyte resulting in Carbon Dioxide (CO2) formation. Other hydrocarbon gases, such as Methane and Ethane, are also released. The present system and method presented herein relate to detection of any gas formation which is the result of increase in cell temperature and rupture of SEI.
[0016] According to one implementation of a preferred embodiment, the system mainly includes a microprocessor, an array of gas detection sensors, a display unit, as set of jumper wire, and a relay. The array of gas detection sensors may include, but may not be limited to, at least one of MQ 135 or K30 for CO2 detection, MQ2 for Methane, Butane, and Smoke detection, MQ9 for carbon Monoxide and flammable gases detection, MQ 137 for Ammonia detection. According to one feature of the present subject matter, one or more sensors of each type can be implemented at different locations inside the battery pack with one end connected to the microprocessor.
[0017] A range of acceptable value of different gases in ppm is predetermined in the Microprocessor. These values are predefined in the art and are obtained from the datasheet of lithium cell chemistry. As soon as the level of gases in ppm inside the battery pack rises above the predetermined value in the Microprocessor, it gives an alarm and a digital pin of the Microprocessor generates a signal for the Relay or the Battery Management System (BMS) to power off the battery pack.
[0018] According to one feature of the embodiment, an exhaust fan can be used to concentrate the released gases at one section inside the battery pack to further accelerate the detection of gases. Stopping the charging or discharging of the battery pack as the case may be stops the flow of current inside the battery pack thereby removing the source of heat generation in the pack thereby preventing thermal runaway.
[0019] These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description. This summary is provided to produce a selection of concepts in a simplified form. This summary is not intended to identify key features or claimed features of the present invention, nor is it intended to be used to limit the scope of the claimed present invention.

BRIEF DESCRIPTION OF THE DRAWINGS
[0020] So that the manner in which the above recited features of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
[0021] FIG. 1 illustrates a general block diagram of a battery thermal management system 100, according to one embodiment of the present disclosure.
[0022] Fig. 2 illustrates CO2 detecting sensors, according to one embodiment of the present invention.
[0023] Fig. 3 depicts constructional diagram of CO2 sensor, according to one embodiment of the present invention.
[0024] Fig. 4 depicts a method flow diagram, according to one embodiment of the present invention.
[0025] To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.

DETAILED DESCRIPTION
[0026] Various embodiments are described herein for a system and method for collaborating multi-services web applications on a single platform. Numerous specific details are set forth to provide a thorough understanding of the embodiments. It will be understood by those skilled in the art, however, that the embodiments may be practiced without these specific details. In other instances, well-known operations, components and circuits have not been described in detail so as not to obscure the embodiments. It can be appreciated that the specific structural and functional details disclosed herein may be representative and do not necessarily limit the scope of the embodiments.
[0027] Reference throughout the specification to “various embodiments,” “some embodiments,” “one embodiment,” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appear ranches of the phrases “in various embodiments,” “in some embodiments,” “in one embodiment,” or “in an embodiment” in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and /or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
[0029] Fig. 1 illustrates a battery thermal management system 100, referred hereinafter as to the system 100. The system mainly includes, but may not be limited to a microprocessor, an array of the sensors, a display unit, a set of jumper wire and a relay.
[0030] The microprocessor 102 is implemented to process sensory data captured by the set of the sensors 104 and facilitate the signal processing required for thermal management of a battery pack. The microprocessor 102 is coupled with hardware memory denoted by a database repository. Database repository is configured to store all modules configuration and associated data pertaining to the system. The database repository also stores processor-executable process steps for basic operation of the processor(s), such as the process steps of an operating system, a database management system and “device drivers” for allowing the system 100 to interface with computer peripheral devices. These latter process steps are known to those skilled in the art, and need not be described in detail herein.
[0031] One end of each sensor is connected to the microprocessor for communicating data signals pertaining to gas detection. A plurality of sensors of each type can be used at different places inside the battery pack. When gas presence is detected by a sensor, value of the present gas is measured by the microprocessor. The gas value is monitored continuously to determine whether the gas value fall within the predetermined range of allowed value for the respective gas.
[0032] The display unit 106 is coupled to the microprocessor. The display unit 106 could be a touch pad, and/or touch screen, LED/ LCD monitor screen, a flat screen, a laptop screen, a TV screen, and the like. The display unit 106 consisting a display screen is configured to display data in real time. Sensory detection output is processed by the microprocessor and displayed on the display screen in real time. Though the primary function of the display screen is to display sensory data in real time, other system related parameters, such as current status of the battery management system, can also be displayed.
[0033] A relay 108 is coupled to the microprocessor. The relay is controlled by the microprocessor as such to switch off the battery when gas formation is detected and measured as outside the predetermined range allowed for the respective gas. The microprocessor is configured to control a battery management system to shut down the battery if temperature rises up beyond the predetermined range for respective gases.
[0034] The system further includes an exhaust fan fixed at outer side of the cover of the system. The exhaust fan is employed to redirect the gases formed inside the system at one focal or location. Redirection of the scattered gases at one location renders gas detection easier. Gases can be detected effectively.
[0035] Fig. 2 describes CO2 detecting sensor, according to one implementation of the preferred embodiment. CO2 detecting sensor, named as MQ135, is implemented which is used to sense the quality of air. The sensors characterized by different static and dynamic range, accuracy, and sensitivity. The internal circuit and design structure of MQ-135 gas sensor is shown in Figure 2. The sensor mainly consists of two elements, a detector element, which contains catalytic material sensitive to the detected gases, and a reference compensator element, which is inert. Detected gases will burn only on the sensitive element, causing a rise in temperature and as a consequence, a rise in its electrical resistance. Detected gases will not burn on the compensator—its temperature and resistance will remain unchanged. The sensor is composed of a micro ceramic tube 208, Tin Dioxide (SnO2) sensitive layer 200, a measuring electrode 202, electrode line 204 and heater 206 are fixed into a crust made by a plastic and stainless-steel net 210 (Figures 3a and 4b). The heater 206 provides necessary operational conditions for the sensitive components. The enveloped MQ-135 has six pins; four of them are used for signals acquisition and the other two are used for providing heating current (Figure 2).
[0036] Figure 3 illustrates the used gas catalytic type sensor MQ-135, according to preferred embodiment. The internal circuit and design structure of MQ-135 gas sensor is described herein. Normally, a Wheatstone bridge circuit is formed with the sensor elements. A heater 310 is adjusted to maintain a state of balance of the bridge circuit in clean air, free of combustible gases. The measured gas concentration will affect the detector element resistance, denoted as active bead 302, compared against a reference bead 304 which will rapidly rise, causing an imbalance in the bridge circuit, thus producing an output voltage signal. To complete a circuit, resistors 306 and 308 are provided. Digital input is provided at input node 301 and output is measured at an output node 308.
[0037] Figure 4 depicts a method flow diagram in accordance with a preferred embodiment. The method steps include implementing a plurality of sensors 402 inside the battery thermal management system, wherein the plurality of sensors include multiple types of sensors configured to sense multiple parameters. Further, displaying data related to the plurality of sensors in real time 404 on a display unit. Yet further, if the plurality of sensors indicate rise in temperature inside the energy storage device, shutting off the energy storage device by controlling a battery management system and/or switching off the energy storage device by controlling a relay 406 coupled between the microprocessor and a battery management system of the energy storage device.
[0038] While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. Accordingly, the appended claims should be construed to encompass not only those forms and embodiments of the invention specifically described above, but to such other forms and embodiments as may be devised by those skilled in the art without departing from its true spirit and scope.