Cooling system for battery pack or chip based on composite thermoelectric material

Abstract

The invention discloses a composite thermoelectric material-based battery pack or chip cooling system, which comprises a battery pack thermal management system, a thermoelectric cooling system and a heat dissipation system, and is characterized in that the battery pack thermal management system is respectively connected with the thermoelectric cooling system and the heat dissipation system; the thermoelectric cooling system and the heat dissipation system are arranged on the battery pack; heat energy emitted by the battery pack is converted into electric energy through a thermoelectric cooling system, and the electric energy is stored; voltage information of the converted electric energy is obtained through the battery pack heat management system, temperature information is obtained according to the voltage information, the temperature information is judged, and the heat dissipation system is controlled based on the judgment result; and cooling the battery pack by using the stored electric energy through a heat dissipation system, wherein the heat dissipation system adopts medium heat absorption and heat dissipation and shock wave heat dissipation operations.

Description

Technical Field

[0001] The present invention belongs to the technical field of battery management, and in particular relates to a cooling system for a battery pack or chip based on composite thermoelectric materials. Background Art

[0002] The battery pack cooling system is a key component in electric vehicles or energy storage systems for maintaining the battery pack within a suitable temperature range. The battery pack cooling system is a complex thermal management system designed to reduce the temperature of the battery pack by circulating coolant or air to prevent the battery from overheating, thereby ensuring the performance, life and safety of the battery. The working principle of the battery pack cooling system is mainly based on the principle of heat exchange. According to the different cooling media, it can be divided into the following types: Natural cooling: a passive method that relies on ambient temperature for heat dissipation, using natural convection of air to dissipate heat, and does not require additional energy input. This method is low-cost, energy-free and does not require additional space, but the heat dissipation efficiency is low. Air cooling: actively promote air flow by adding fans to improve the heat dissipation effect. The advantages of the air cooling system are low cost, low energy consumption, mature technology, easy control and maintenance. However, its cooling effect is still affected by the ambient temperature, and an additional heating system is required in cold weather. Liquid cooling: efficient heat dissipation is achieved by circulating coolant in the battery pack. The advantages of the liquid cooling system are that the cooling efficiency is much higher than air cooling, and the battery can be heated at the same time by heating the coolant. The disadvantage is that the liquid cooling system is relatively heavy, will take up a certain amount of battery space, and the system structure is complex, with many components, requiring high sealing, there is a risk of liquid leakage, and the subsequent maintenance cost is high. At the same time, the battery pack cooling system generally collects relevant temperature information through relevant temperature sensing elements, but it is only information collection and cannot effectively utilize the dissipated heat. In summary, the existing battery pack cooling system has the problem of not being able to effectively balance cost, energy consumption and cost, and the dissipated heat cannot be effectively used. Summary of the invention

[0003] In order to solve the above technical problems, the present invention proposes a cooling system for a battery pack or chip based on composite thermoelectric materials to solve the above problems existing in the prior art.

[0004] To achieve the above object, the present invention provides a cooling system for a battery pack or chip based on a composite thermoelectric material, comprising:

[0005] A battery pack thermal management system, a thermoelectric cooling system and a heat dissipation system, wherein the battery pack thermal management system is connected to the thermoelectric cooling system and the heat dissipation system respectively; the thermoelectric cooling system and the heat dissipation system are arranged on the battery pack;

[0006] Converting the thermal energy emitted by the battery pack into electrical energy through a thermoelectric cooling system, and storing the electrical energy;

[0007] Acquiring voltage information of the converted electric energy through a battery pack thermal management system, obtaining temperature information according to the voltage information, judging the temperature information, and controlling the heat dissipation system based on the judgment result;

[0008] The battery pack is cooled using the stored electrical energy through a heat dissipation system, wherein the heat dissipation system adopts dielectric heat absorption and shock wave heat dissipation operations.

[0009] Optionally, the thermoelectric cooling system uses a first thermoelectric material based on the Seebeck effect, and the first thermoelectric material is arranged in an array.

[0010] Optionally, the heat dissipation system includes an air cooling system and a liquid cooling system, wherein the air cooling system dissipates heat from the battery pack by shock wave heat dissipation, and the liquid cooling system dissipates heat from the battery pack by dielectric heat absorption and heat dissipation.

[0011] Optionally, the liquid cooling system uses a second thermoelectric material based on the Peltier effect, and the second thermoelectric material is arranged in an array.

[0012] Optionally, a MEMS piezoelectric film is used in the air cooling system, wherein the MEMS piezoelectric film is arranged in an array.

[0013] Optionally, the heat dissipation system includes a plurality of heat dissipation units, wherein the heat dissipation unit includes a second thermoelectric material based on the Peltier effect and a MEMS piezoelectric film, the second thermoelectric material includes a heat absorption end and an input end, a substrate is arranged on the input end, and a MEMS piezoelectric film is fixedly arranged on the other side of the substrate; the second thermoelectric material is fixed on the battery pack, and the second thermoelectric material is used as a supporting wall to fix the MEMS piezoelectric film, and the heat dissipation units are arranged in an array.

[0014] Optionally, in the battery pack thermal management system, the temperature information acquisition process includes:

[0015] The voltage information of the converted electric energy is obtained, and the voltage information is calculated according to the Seebeck coefficient to obtain the temperature information.

[0016] Optionally, the thermoelectric cooling system and the heat dissipation system are arranged on the battery pack including: the thermoelectric cooling system and the heat dissipation system are arranged sequentially or in parallel between the batteries in the battery pack, or the thermoelectric cooling system and the heat dissipation system are arranged between the batteries in the battery pack, and the heat dissipation system is arranged on one side of the battery pack.

[0017] Optionally, in the heat dissipation unit, the positive and negative input terminals of the piezoelectric film are connected with the positive and negative input terminals of the second thermoelectric material in the same polarity, and power is supplied preferentially through the converted electric energy, and secondarily through an external power source.

[0018] Optionally, the battery pack thermal management system, thermoelectric cooling system and heat dissipation system are also used to perform temperature detection and heat dissipation on the chip.

[0019] Compared with the prior art, the present invention has the following advantages and technical effects:

[0020] The present invention uses the Seebeck effect to detect temperature and utilize waste heat energy through a thermoelectric cooling system, and the waste heat is converted into electrical energy to provide electrical energy for the heat dissipation system. The liquid cooling system and the air cooling system in the heat dissipation system respectively use the Peltier effect and the piezoelectric film vibration principle to dissipate heat. During heat dissipation, both the Peltier effect material and the piezoelectric film can utilize the electrical energy converted from waste heat to reduce external energy consumption. At the same time, the piezoelectric film and the Peltier effect material can achieve the effect of heat dissipation at a relatively low cost. The above-mentioned heat dissipation device is relatively small in size, and the battery pack is dissipated as a whole through an array arrangement, which also reduces the size of the heat dissipation device. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings constituting a part of the present application are used to provide a further understanding of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0022] Figure 1 A structural diagram of a cooling system for a battery pack or chip based on composite thermoelectric materials according to an embodiment of the present invention;

[0023] Figure 2 It is a configuration diagram of a thermoelectric cooling system, an air cooling system and a liquid cooling system according to an embodiment of the present invention;

[0024] Figure 3 This is a schematic diagram of a thermoelectric material of the Seebeck effect according to an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram of a thermoelectric material of the Peltier effect according to an embodiment of the present invention;

[0026] Figure 5 A schematic diagram of a combination of a thermoelectric material and a piezoelectric film of the Peltier effect according to an embodiment of the present invention;

[0027] Figure 6 A schematic diagram of the arrangement of heat dissipation units according to an embodiment of the present invention;

[0028] Figure 7 A schematic diagram of power supply and heat dissipation for a heat dissipation unit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0029] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0030] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0031] like Figure 1 As shown, in this embodiment, a cooling system for a battery pack or chip based on a composite thermoelectric material is provided, comprising:

[0032] Battery pack thermal management system, thermoelectric cooling system, air cooling system and liquid cooling system; the thermoelectric cooling system, air cooling system and liquid cooling system are all arranged on the battery pack; the battery pack thermal management system is respectively connected to the thermoelectric cooling system, air cooling system and liquid cooling system to control the thermoelectric cooling system, air cooling system and liquid cooling system.

[0033] The thermoelectric cooling system is used to obtain the temperature information of the battery pack and convert the heat emitted by the battery pack into electrical energy and store it in the battery energy storage system.

[0034] The battery pack thermal management system is used to turn on the liquid cooling system and air cooling system for cooling according to the temperature information of the battery pack;

[0035] The liquid cooling system is used to control the temperature exchange between materials of the battery pack by using an external power supply to cool the battery pack;

[0036] The air cooling system is used to ventilate and cool the battery pack using the electrical energy converted by the thermoelectric cooling system.

[0037] Among them, the thermoelectric cooling system mainly uses thermoelectric materials with Seebeck effect, the liquid cooling system mainly uses thermoelectric materials with Peltier effect, and the air cooling system mainly uses MEMS piezoelectric films.

[0038] The air cooling system or liquid cooling system and the thermoelectric cooling system can be combined according to the actual heating conditions of the battery pack. The thermoelectric cooling system is mainly used for battery waste heat utilization and cooling management.

[0039] In a practical setting, Figure 2 As shown, the battery pack includes a plurality of square or cylindrical batteries, and the air cooling system and the liquid cooling system can be arranged between the batteries in different orders and can be arranged in sequence in different directions ( Figure 2 A / B in ), or parallel settings in different directions ( Figure 2 C / D in the figure), or setting the thermoelectric cooling system between the batteries and setting the air cooling and liquid cooling systems at both ends of the battery ( Figure 2 The setting method can be adjusted according to actual needs, and will not be described in detail. In addition to batteries, it can also be extended to other scattering scenarios, such as chips or other heating elements ( Figure 2 F).

[0040] The battery pack thermal management system mainly uses the battery pack thermal management system, which controls and manages the air cooling or liquid cooling system and the thermoelectric cooling system. Thermoelectric power generation can be supplied to the energy storage system.

[0041] For the thermoelectric cooling system, it mainly uses thermoelectric materials with Seebeck effect. For the convenience of explanation, it is defined as the first thermoelectric material, and the Seebeck effect is explained as follows:

[0042] Seebeck effect: Thermoelectric power generation is a technology that directly converts thermal energy into electrical energy. It is mainly based on the principle of Seebeck effect for thermal energy detection and electrical energy conversion.

[0043] First thermoelectric material: Thermoelectric materials based on the Seebeck effect are usually composed of P-type and N-type semiconductors, and the P-type and N-type semiconductors form a PN pair. Among them, in the PN pair, one end of the P-type semiconductor is connected to one end of the N-type semiconductor, connected through a line or a substrate, as a high-temperature end, used to contact or approach a heat source (battery) to increase the temperature of this end, and the other end is used as a low-temperature end to form a temperature difference. At the same time, the low-temperature end is used to connect to the energy storage system and output related electrical energy to the energy storage system for storage.

[0044] Among them, thermoelectric materials include semiconductor thermoelectric materials, oxide thermoelectric materials, metal thermoelectric materials, organic thermoelectric materials, etc. Among them, semiconductor thermoelectric materials include: lead telluride (PbTe), bismuth telluride alloy (Bi2Te3), silicon germanium alloy (SiGe), etc. These materials have high thermoelectric conversion efficiency in the medium and low temperature range (300K-600K). They have good thermoelectric performance, but the cost is relatively high. Oxide thermoelectric materials: This type of material has high chemical stability and oxidation stability, such as sodium cobalt oxide (NaCo2O4), including strontium titanate (SrTiO3), perovskite structure oxides, etc. These materials have good thermoelectric performance and chemical stability in high temperature areas. Metal thermoelectric materials include: cobalt-based alloys (CoSb3), nickel-based alloys (NiSi), etc. These materials show good thermoelectric performance in high temperature areas (above 600K). Organic thermoelectric materials include: conductive polymers (PEDOT:PSS), carbon nanotubes (CNTs), etc. These materials have the advantages of flexibility and light weight, and are suitable for wearable devices and flexible electronic devices. For example, purified p-type and n-type CNTs have great potential as thermoelectric materials in semiconducting carbon nanotubes (CNTs) containing impurities.

[0045] Temperature difference generates electric potential: When there is a temperature difference between the two ends of a thermoelectric material, the carriers (electrons or holes) will diffuse from the high temperature end to the low temperature end, thereby generating an electric potential difference between the two ends of the material. This enables the conversion of thermal energy into electrical energy. When the temperatures at both ends of a PN pair are different, such as Figure 3 As shown in the figure, the residual heat of the battery pack is absorbed by the heat absorbing end (PN to the top) and then the hole e + , electronic - Each diffuses toward the heat release end to form an electric potential difference, which will generate current in the circuit, and the generated electricity will be sent to the energy storage system, thus realizing "temperature difference power generation".

[0046] The voltage generated across the conductor is proportional to the temperature gradient across them. The proportionality constant is called the thermoelectric potential or Seebeck coefficient. In other words, the change in temperature difference and the corresponding change in voltage generated are related by the Seebeck coefficient. The relationship between the rate of change of temperature and the change in voltage is:

[0047] V=–S(Th–Tl)

[0048] Among them, V represents the potential difference between the two thermoelectric materials at the cold end, that is, the voltage, S represents the Seebeck coefficient, Th represents the hot end temperature, and Tl represents the cold end temperature, which represents the current indoor temperature information;

[0049] Or, δV = –S(δT)

[0050] Among them, δV represents the voltage change, and δT represents the temperature difference change.

[0051] The Seebeck coefficient in its standard form is defined as the amount of voltage V1 developed between two conductors when the temperature across them is maintained at 1 Kelvin throughout the observation period, that is, S = –V1.

[0052] At this time, when there is a temperature difference at both ends of the PN pair, the PN pair can continue to use the waste heat of the heat source to generate electricity, and the voltage on a pair of PN pairs is in the millivolt level.

[0053] The Seebeck voltage and current of the PN pair become one of the thermal indicators of the battery, which helps to accurately manage the battery thermal system.

[0054] The thermoelectric cooling system mainly uses the above-mentioned thermoelectric material based on the Seebeck effect. During the temperature detection process, the first thermoelectric material can be connected in parallel to the energy storage system or connected to the energy storage system alone to perform temperature detection on the entire or individual position in the battery pack. During the temperature detection process, the rate of change of the temperature can be calculated by detecting the rate of change of the voltage, and then the temperature information can be obtained.

[0055] During the energy storage process, the first thermoelectric material can be arranged in an array and connected to the energy storage system in parallel in the array to effectively collect and utilize the waste heat in the battery pack. During the collection process, the voltage is detected by the battery pack thermal management system, and the voltage change rate of each thermoelectric material is calculated by the mean, and then the average temperature change rate of the battery pack is calculated. Taking a certain temperature as a reference and combining the calculated temperature change rate, the current temperature information can be obtained. Under this temperature information, the battery pack thermal management system performs relevant threshold or manual experience judgment to control whether the subsequent liquid cooling and air cooling systems are turned on for cooling.

[0056] In the liquid cooling system, the temperature is mainly reduced by the thermoelectric material of the Peltier effect. For the convenience of explanation, it is defined as the second thermoelectric material to explain the Peltier effect:

[0057] Peltier effect: Peltier effect and Seebeck effect are inverse effects of each other. If it is not necessary to let heat flow drive charge flow, such as Figure 4 , but instead use an external potential to drive the heat-carrying charge, which can force heat to flow from one end to the other.

[0058] The second thermoelectric material, the thermoelectric material based on the Peltier effect, is also composed of P-type and N-type semiconductors, and the P-type and N-type semiconductors form a PN pair, but the semiconductor type involved in the Seebeck effect is different. The thermoelectric material based on the Peltier effect is the same as the thermoelectric material based on the Seebeck effect. The above two effects are inverse effects to each other, and the material can produce the above two effects under different conditions.

[0059] Among them, in the PN electrical pair, one end of the P-type semiconductor is connected to one end of the N-type semiconductor through a line or a substrate, serving as a heat-absorbing end for contacting or approaching a heat source (battery) to absorb heat energy, and the other end serves as an input end for inputting electrical energy, and the input end is used to connect to an external power source.

[0060] When the heat source continues to generate heat and there is no temperature difference between the two ends of the PN electrode pair, the Seebeck voltage and current are zero. At this time, the control system starts the external power supply to continue cooling the heat source.

[0061] Principle of Peltier effect:

[0062] Differences in Fermi levels of different materials: Electrons in different materials have different energy levels (Fermi levels). When current flows through the junction of two different materials, electrons will jump from a high energy level to a low energy level, or from a low energy level to a high energy level.

[0063] Energy absorption or release: During the electron transition process, energy absorption or release will occur. If the electron transitions from a high energy level to a low energy level, the excess energy will be released in the form of heat, causing the temperature of the connection to rise; conversely, if the electron transitions from a low energy level to a high energy level, energy needs to be absorbed, causing the temperature of the connection to drop.

[0064] The Peltier effect describes the phenomenon of heat absorption or heat release when current flows through the junction of two different conductors or semiconductors. Its basic formula is:

[0065] Q=Π·I

[0066] Where: Q represents the heat generated at the node per unit time (W), Π represents the Peltier coefficient (V / K), which represents the product of the heat generated when a unit current passes through the node and the temperature gradient, and I represents the current passing through the node (A)

[0067] The above formula shows that in the Peltier effect, the heat generated is proportional to the current and the Peltier coefficient. Considering the temperature gradient, in practical applications, it is usually necessary to consider the effect of temperature gradient on the Peltier effect. Therefore, a more complete formula can be written as: dQ = Π·I·dT

[0068] Where: dQ: small change in heat, dT: small change in temperature, d represents the differential sign, which indicates the instantaneous rate of change of subsequent parameters.

[0069] The Peltier coefficient reflects the difference in electronic energy levels of different materials and is an important parameter that characterizes the strength of the Peltier effect. Its positive and negative signs determine the direction of heat flow: Π>0: When the current flows from the high-energy-level material to the low-energy-level material, the node absorbs heat. Π<0: When the current flows from the low-energy-level material to the high-energy-level material, the node releases heat.

[0070] When the battery pack thermal management system detects thermal runaway of the heat source, for example, greater than 100°C, it immediately calls on an external power source to cool the heat source. This is a forced cooling method.

[0071] Regarding the second thermoelectric material in the liquid cooling system, an array arrangement can be selected and connected in parallel or in series. After the connection, the second thermoelectric material array is powered by an external power supply, and the battery pack is subjected to heat absorption or cooling operation through the above-mentioned Peltier effect. The liquid cooling system can be set between the batteries or at the top or bottom of the battery pack for cooling operation.

[0072] In the air cooling system, the MEMS piezoelectric film mainly relies on the MEMS piezoelectric film vibration heat dissipation principle to perform cooling operations. The heat dissipation principle of the piezoelectric film is as follows:

[0073] MEMS piezoelectric film vibration heat dissipation principle:

[0074] MEMS piezoelectric film vibration heat dissipation is an emerging active heat dissipation technology. It uses MEMS (micro-electromechanical system) technology and uses piezoelectric film as the core component to generate high-frequency vibrations to drive the flow of surrounding air, thereby achieving efficient heat dissipation. Piezoelectric film is a micro sensor or actuator that uses the piezoelectric effect. When a piezoelectric material is subjected to an applied electric field, the material will undergo mechanical deformation. Piezoelectric film is usually made of materials such as PZT (lead zirconate titanate) or AlN (aluminum nitride) and has high sensitivity and high stability.

[0075] How it works

[0076] Piezoelectric effect: When voltage is applied to a piezoelectric film, the film undergoes mechanical deformation and generates vibrations.

[0077] Vibration generates airflow: The high-frequency vibration of the piezoelectric film will produce a micro air pump effect around it, driving the air flow.

[0078] Heat transfer: Air flow removes heat from the heat source, thereby dissipating heat.

[0079] It has the following characteristics: High-efficiency heat dissipation: Compared with traditional fan heat dissipation, MEMS piezoelectric film vibration heat dissipation has higher heat dissipation efficiency. Low noise: Due to the high vibration frequency, it is difficult for the human ear to perceive, so the noise is extremely low. Small size and light weight: MEMS devices are miniaturized and are very suitable for use in small electronic devices. No wear: There are no mechanical rotating parts, so there is no wear problem and the life is longer. Strong controllability: By adjusting the applied voltage, the size and direction of the airflow can be precisely controlled.

[0080] Common MEMS piezoelectric film materials can be used:

[0081] Zinc oxide (ZnO): has a high piezoelectric coefficient and mechanical quality factor, aluminum nitride (AlN): has good thermal stability and chemical stability, lithium niobate (LiNbO3): has a high piezoelectric coefficient and optical activity. Piezoelectric polymer (PVDF): good flexibility and low cost.

[0082] Piezoelectric equation: describes the relationship between the electric field and mechanical strain of piezoelectric materials.

[0083] S=sE*E+d*E

[0084] D=dT*T+ε*E

[0085] Where: S is strain, sE is the elastic compliance matrix, E is the electric field intensity, d is the piezoelectric constant matrix, D is the electric displacement, T is the stress, and ε is the dielectric constant matrix.

[0086] Mechanical equilibrium equation: the equation that describes the vibration of the membrane.

[0087]

[0088] Where: ρ is the film density, u is the displacement of the film, t is the time, σ is the stress, and x is the spatial coordinate.

[0089] Heat conduction equation: describes the change of temperature field over time.

[0090]

[0091] Where: ρc is the specific heat capacity, T is the temperature, and Q is the heat source

[0092] Fluid Mechanics Equations

[0093] Navier-Stokes equations: describe the motion of viscous incompressible fluids.

[0094]

[0095] Where: ρ is the fluid density, u is the fluid velocity, p is the pressure, μ is the dynamic viscosity, and g is the gravitational acceleration.

[0096] The Daqing Demonstration Base released energy storage data: air conditioning losses accounted for a high proportion; in terms of auxiliary system losses, the total loss of lithium iron phosphate energy storage (0.5C) of different technology energy storage battery systems was the highest at 22061kWh, and the lowest total loss was 7899.5kWh for all-vanadium liquid flow. Air conditioning losses accounted for a high proportion of auxiliary system losses, accounting for 45%-80% of the total losses. Refrigeration and air conditioning have become the primary loss of power or energy storage.

[0097] For MEMS piezoelectric films, they can be directly arranged on the battery pack in an array, and driven by the thermoelectric voltage generated by the Seebeck effect or the electrical energy in the energy storage system to perform ventilation and cooling operations.

[0098] like Figure 5 As shown, the MEMS piezoelectric film can be combined with the second thermoelectric material in the above-mentioned air-cooling system to form a heat dissipation unit for heat dissipation, in which the second thermoelectric material is combined with the piezoelectric film, wherein a substrate is fixedly set at the bottom of the input end of the P-type semiconductor and the N-type semiconductor in the second thermoelectric material, and the piezoelectric film is fixed on the substrate, and the current input end of the piezoelectric film can be set between the substrate and the piezoelectric film or at other positions, and the heat absorption end of the second thermoelectric material is fixed on the battery pack. At this time, the second thermoelectric material directly contacts the battery pack for direct heat exchange to perform liquid cooling. At the same time, the second thermoelectric material acts as a support arm to support and fix the piezoelectric film for vibration, and the vibration of the piezoelectric film forms a shock wave for heat dissipation.

[0099] The input end of the piezoelectric film and the input end of the second thermoelectric material can be set separately, wherein the second thermoelectric material can be provided with electric energy through the energy storage system or an external power supply, and the piezoelectric film is mainly provided with electric energy through the energy storage system. When the energy storage system is insufficient, the external power supply is selected to provide electric energy to perform heat dissipation operation on the whole.

[0100] The positive and negative input terminals of the piezoelectric film and the positive and negative input terminals of the second thermoelectric material can be connected in the same polarity as the unified positive and negative input terminals of the second thermoelectric material and the piezoelectric film. At this time, the energy storage system is used first to provide power. If the energy storage system is insufficient, an external power supply is used to provide power.

[0101] The heat dissipation units are arranged in an array and receive electrical energy in parallel or series to dissipate heat to the battery pack over a large area.

[0102] At the same time, as an option, the second electrothermal material and piezoelectric film in the heat dissipation unit can be arranged in the above structure, but the voltage input ends are arranged separately, the input end of the piezoelectric film is connected to the energy storage system, the piezoelectric film is powered by the electric energy generated by the first thermoelectric material, and the second electrothermal material is powered by an external power supply.

[0103] The heat dissipation unit is controlled according to the scenario and the corresponding power usage. When a laptop computer or other small mobile device reaches a certain temperature through the first thermoelectric material detection, the electric energy provided by the first hot spot material directly controls the piezoelectric film in the heat dissipation unit to vibrate and dissipate heat. At this time, the second thermoelectric material only serves as a support arm to support the piezoelectric film without performing heat dissipation. When it is aimed at a large energy storage battery pack or other large heat dissipation scenarios, the first thermoelectric material is used for temperature detection and power generation, and the second hot spot material and the piezoelectric film are used together to dissipate heat.

[0104] The piezoelectric film is powered by the electric energy generated by the first thermoelectric material, wherein the array structure of the heat dissipation unit can be arranged in different regions, and the array structure corresponding to the first thermoelectric material is arranged in the same way in different regions, and the piezoelectric film is powered by the electric energy provided by the first thermoelectric material in the corresponding region. In different regions, the vibration frequency or ventilation of the piezoelectric film may be different due to the different power generation in different regions. The more power generation, the greater the vibration frequency, and thus the better the ventilation effect. On this basis, adaptive heat dissipation can be performed on regions at different temperatures without the need for additional control logic.

[0105] Furthermore, the piezoelectric film can be matched one-to-one with the first thermoelectric material according to the same position, and a first thermoelectric material can be directly used to power a piezoelectric film. Within the temperature threshold range, the inherent vibration frequency of the same material is fixed. When the temperature in a certain area is high, the thermoelectric current is large and the amplitude is large, while when the temperature in a certain area is low, the thermoelectric current is small and the amplitude is small; finally, they tend to the same temperature. This does not require special measurement and programming for automatic control, and the characteristics of the material itself can achieve the effect of precise automatic control. Under this concept, a variety of technical solutions can be extended, which will not be elaborated here.

[0106] The piezoelectric film can also be powered by an external power supply in conjunction with the power supply in the energy storage system, or an external power supply can be selected; the way in which the energy storage system and the external power supply power the cooling system can be adjusted in a variety of conventional ways based on the above technical solution to achieve different heat dissipation effects, which will not be elaborated here.

[0107] It should also be noted that this heat dissipation method can also be used to cool other devices that require heat dissipation. For example, the computing chip can be repackaged to dissipate heat. The devices that require heat dissipation are not described in detail here.

[0108] The present invention can reduce losses. It does not require internal or external power sources to provide vibration heat dissipation. The heat source itself is directly used for thermoelectric power generation and heat dissipation, which of course reduces energy consumption from the system. At present, heat dissipation is provided by internal or external power sources, and the energy consumption is very large. For example, large energy storage cabinets directly use external power sources, air conditioners and liquid cooling to dissipate heat. Electric vehicles use their own battery packs to drive electric heat pumps to dissipate heat using air cooling or liquid cooling modes. This solution uses heat to dissipate heat and reduce energy consumption.

[0109] In the present invention, PN pairs are used as cantilever support arms, and the thermoelectric voltage generated by the Seebeck effect is used as the vibration power source of the MEMS piezoelectric film, which is then arranged into an array of thousands of such as Figure 6 The array fans the air together. Due to the same vibration frequency, shock wave heat dissipation can be easily formed. Usually, there is no need to connect an external power supply. This can greatly reduce power consumption and achieve a very good heat dissipation effect.

[0110] When overheating, Figure 7 , use the battery pack thermal management system to reverse input current, which can dissipate heat through vibration shock waves and Peltier effect cooling and heat dissipation.

[0111] The above are only preferred specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A cooling system for a battery pack or chip based on composite thermoelectric materials, characterized in that: include: A battery pack thermal management system, a thermoelectric cooling system and a heat dissipation system, wherein the battery pack thermal management system is connected to the thermoelectric cooling system and the heat dissipation system respectively; the thermoelectric cooling system and the heat dissipation system are arranged on the battery pack; Converting the thermal energy emitted by the battery pack into electrical energy through a thermoelectric cooling system, and storing the electrical energy; Acquiring voltage information of the converted electric energy through a battery pack thermal management system, obtaining temperature information according to the voltage information, judging the temperature information, and controlling the heat dissipation system based on the judgment result; The battery pack is cooled using the stored electrical energy through a heat dissipation system, wherein the heat dissipation system adopts dielectric heat absorption and shock wave heat dissipation operations.

2. The system according to claim 1, characterized in that The thermoelectric cooling system adopts a first thermoelectric material based on the Seebeck effect, and the first thermoelectric material is arranged in an array.

3. The system according to claim 1, characterized in that The heat dissipation system includes an air cooling system and a liquid cooling system, wherein the air cooling system dissipates heat from the battery pack by means of shock wave heat dissipation, and the liquid cooling system dissipates heat from the battery pack by means of medium heat absorption and heat dissipation.

4. The system according to claim 3, characterized in that The liquid cooling system uses a second thermoelectric material based on the Peltier effect, and the second thermoelectric material is arranged in an array.

5. The system according to claim 3, characterized in that The air cooling system uses a MEMS piezoelectric film, wherein the MEMS piezoelectric film is arranged in an array.

6. The system according to claim 3, characterized in that The heat dissipation system includes a plurality of heat dissipation units, wherein the heat dissipation unit includes a second thermoelectric material based on the Peltier effect and a MEMS piezoelectric film, the second thermoelectric material includes a heat absorption end and an input end, a substrate is arranged on the input end, and a MEMS piezoelectric film is fixedly arranged on the other side of the substrate; the second thermoelectric material is fixed on the battery pack, and the second thermoelectric material is used as a supporting wall to fix the MEMS piezoelectric film, and the heat dissipation units are arranged in an array.

7. The system according to claim 2, characterized in that In the battery pack thermal management system, the temperature information acquisition process includes: The voltage information of the converted electric energy is obtained, and the voltage information is calculated according to the Seebeck coefficient to obtain the temperature information.

8. The system according to claim 1, characterized in that The manner in which the thermoelectric cooling system and the heat dissipation system are arranged on the battery pack includes: the thermoelectric cooling system and the heat dissipation system are arranged sequentially or in parallel between the batteries in the battery pack, or the thermoelectric cooling system and the heat dissipation system are arranged between the batteries in the battery pack, and the heat dissipation system is arranged on one side of the battery pack.

9. The system according to claim 6, characterized in that In the heat dissipation unit, the positive and negative input terminals of the piezoelectric film are connected with the positive and negative input terminals of the second thermoelectric material in the same polarity, and are powered by the converted electric energy first, and secondly by an external power source.

10. The system according to claim 1, characterized in that The battery pack thermal management system, thermoelectric cooling system and heat dissipation system are also used to detect the temperature of the chip and dissipate heat.

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