UPS battery temperature control structure and temperature control method thereof

Abstract

The invention discloses a UPS battery temperature control structure and a temperature control method thereof, and the structure comprises a battery module, a thermoelectric coupling layer, and a heat insulation housing. The battery module consists of a plurality of battery units, and unit gaps are filled with a composite phase change material; the thermoelectric coupling layer comprises a semiconductor thermoelectric module array and a heat conduction assembly, and precise heat conduction is achieved through bidirectional temperature control of semiconductor thermoelectric modules and directional heat conduction of heat pipes. The heat insulation shell comprises an inner aerogel heat insulation layer and a radiation coating and isolates external extreme temperature interference. The temperature control method comprises the steps of monitoring the battery temperature, the environment temperature and the phase change state of the composite phase change material in real time, dynamically selecting a pure composite phase change material buffer mode and a semiconductor thermoelectric module active or mixed mode, and generating power and recharging energy by using the temperature difference of the cold end and the hot end of the semiconductor thermoelectric module. Through the synergistic effect of the composite phase change material, the semiconductor thermoelectric module and the shell, the temperature of the battery can be stabilized without external constant temperature equipment, and the temperature control energy consumption is low.

Description

Technical Field

[0001] The present invention relates to the field of UPS batteries, and specifically, to a temperature control structure for a UPS battery and a temperature control method therefor. Background Art

[0002] An uninterruptible power supply (UPS) is a device that provides emergency power protection for critical loads. It can achieve zero-delay switching power supply through a built-in battery pack when the mains power is interrupted or abnormal, and is widely used in fields such as data centers, medical facilities, and industrial control. As the core energy storage unit of the UPS system, the battery pack usually uses lead-acid batteries or lithium batteries, and its performance directly affects the endurance and reliability of the UPS. Especially under complex working conditions such as high temperature, low temperature, and frequent charging and discharging, the stability and life of the battery become the key factors restricting the overall efficiency of the UPS.

[0003] Existing UPS batteries have significant performance defects in extreme temperature environments (high temperature > 40°C or low temperature < -10°C): high temperature causes the electrolyte evaporation of lead-acid batteries to accelerate and the electrode plates to corrode, while lithium batteries face the risk of thermal runaway; in low temperature environments, the internal resistance of the battery surges and the available capacity drops sharply, and in extreme cases, it cannot even discharge normally. To maintain the working temperature of the battery, existing technologies mostly rely on external temperature control devices (such as air conditioners, heaters). Such solutions require continuous consumption of additional energy, and are difficult to deploy in harsh scenarios such as high altitudes and outdoors, resulting in a significant increase in system energy consumption and operation and maintenance costs, and it is difficult to meet the lightweight and high reliability requirements of emerging application scenarios such as distributed energy storage and mobile base stations. Summary of the Invention

[0004] The main object of the present invention is to provide a temperature control structure for a UPS battery and a temperature control method therefor, aiming to realize the adaptive adjustment of the battery temperature through the synergistic effect of the heat buffering characteristics of the phase change material (PCM) and the precise temperature control ability of the semiconductor thermoelectric module (TEC), and combine with an intelligent algorithm to maintain the stable performance of the battery at extreme temperatures (-40°C to 70°C) without relying on external air conditioners or heating devices. At the same time, the thermoelectric generation at the hot and cold ends of the TEC is used to realize the closed-loop utilization of energy, significantly reducing the system energy consumption and operation and maintenance costs, extending the battery cycle life, and meeting the high reliability requirements of harsh scenarios such as outdoor base stations and new energy power stations.

[0005] The technical solution of the present invention is as follows:

[0006] To achieve the above object, the present invention provides a temperature control structure for a UPS battery, which is characterized by comprising a battery module, a thermoelectric coupling layer, and a heat insulation shell;

[0007] The battery module includes a plurality of battery cells, and a composite phase change material is filled between the battery cells;

[0008] The thermoelectric coupling layer surrounds the outside of the battery module. The thermoelectric coupling includes a semiconductor thermoelectric module array and a heat conduction component;

[0009] The heat insulation housing is sleeved outside the thermoelectric coupling layer. The heat insulation housing includes a heat insulation layer and a radiation coating, and the heat insulation layer is located inside the radiation coating.

[0010] In a possible implementation manner, the composite phase change material is prepared by melt blending lauric acid, stearic acid and graphene oxide. The mass ratio of graphene oxide is 5%-15%. The layer thickness of the graphene oxide is ≤5nm. The mass mixing ratio of lauric acid and stearic acid is 1:1 to 1:3.

[0011] In a possible implementation manner, the semiconductor thermoelectric module array is independently partition controlled, and each semiconductor thermoelectric module corresponds to a battery cell.

[0012] In a possible implementation manner, the heat conduction component includes heat conduction fins and heat pipes. One end of the heat pipe is connected to the hot end of the semiconductor thermoelectric module, and the other end extends to the outside of the heat insulation housing. The heat conduction fins are located outside the heat insulation housing, and the heat conduction fins are connected to the heat pipe.

[0013] In a possible implementation manner, the heat insulation layer is composed of silica aerogel and silicon carbide nanofibers. The mass fraction of the silicon carbide nanofibers is 5%-10%. The silicon carbide nanofibers are embedded in the silica aerogel matrix. The thickness of the heat insulation layer is 3-8mm. The radiation coating is composed of titanium dioxide particles and polydimethylsiloxane. The mass ratio of the titanium dioxide particles is 60%-80%. The particle size range of the titanium dioxide particles is 200nm-400nm. The titanium dioxide particles are embedded in the polydimethylsiloxane matrix in a disordered stacking manner.

[0014] For the temperature control method of the UPS battery temperature control structure as described in any one of the above, it is characterized by including the following steps:

[0015] S100. Real-time monitor the battery temperature, ambient temperature and the phase change state of the composite phase change material;

[0016] S200. Dynamically select the pure composite phase change material buffering mode, the semiconductor thermoelectric module active temperature control mode or the hybrid mode according to the temperature threshold and the composite phase change material state;

[0017] S300. In the semiconductor thermoelectric module active temperature control mode, adjust the power of the semiconductor thermoelectric module based on the temperature difference, and conduct heat directionally through the heat conduction component;

[0018] S400. Recover energy using the temperature difference between the hot and cold ends of the semiconductor thermoelectric module, and recharge the generated electric energy to the battery.

[0019] In a possible implementation, the phase change state of the composite phase change material is determined in the following manner:

[0020] When the battery temperature exceeds the phase change temperature of the composite phase change material and the duration exceeds the threshold, it is determined that the composite phase change material enters the liquid state;

[0021] When the battery temperature is lower than the phase change temperature of the composite phase change material and the impedance change rate exceeds the set value, it is determined that the composite phase change material returns to the solid state.

[0022] In a possible implementation, the logic of the dynamic selection mode includes:

[0023] If the battery SOC < 20%, the active temperature control mode of the semiconductor thermoelectric module is disabled, and only rely on the composite phase change material for buffering and the radiation coating for passive heat dissipation or heat preservation.

[0024] In a possible implementation, in the hybrid mode, the latent heat absorption or release of the composite phase change material is preferentially utilized, and the semiconductor thermoelectric module is only started after the phase change of the composite phase change material is saturated to supplement the temperature control requirements;

[0025] The power regulation of the semiconductor thermoelectric module adopts the PID algorithm, and the input parameters include the real-time temperature difference, the temperature difference change rate, and the battery load current.

[0026] In a possible implementation, the specific steps of the energy recovery are as follows:

[0027] When the temperature difference between the hot and cold ends of the semiconductor thermoelectric module ≥ 10°C, the semiconductor thermoelectric module is switched to the power generation mode, and the output electric energy is recharged to the battery through the DC-DC converter.

[0028] The technical solution of the present invention realizes the adaptive thermal management of the UPS battery under extreme temperatures (-40°C to 70°C) through the synergistic effect of the thermal buffering ability of the composite phase change material, the precise temperature control of the semiconductor thermoelectric module array, and the multiple passive protections of the heat insulation shell, and solves the problems of high energy consumption, high cost, low-temperature capacity attenuation, and high-temperature life shortening caused by the existing technology's dependence on external constant temperature equipment. Among them, the composite phase change material absorbs instantaneous thermal shocks, the semiconductor thermoelectric module array dynamically compensates for temperature deviations, the heat insulation shell blocks environmental interference, and at the same time, the temperature difference between the hot and cold ends of the semiconductor thermoelectric module is used to generate electricity and recharge energy, forming a closed-loop temperature control system, reducing the battery capacity attenuation rate and the operation and maintenance cost, and significantly improving the reliability of the UPS in harsh scenarios such as outdoor base stations and polar scientific expeditions. Description of the Drawings

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0030] Figure 1 It is the structural block diagram of the UPS battery temperature control structure in Embodiment 1;

[0031] Figure 2 It is the flowchart of the UPS battery temperature control method in Embodiment 2.

[0032] Explanation of the reference numerals in the drawings: 1. Battery unit; 2. Composite phase change material; 3. Semiconductor thermoelectric module; 4. Heat insulation layer; 5. Radiation coating; 6. Heat pipe; 7. Heat conducting fin.

[0033] The realization of the purpose of the present invention, functional characteristics and advantages will be further described in combination with the embodiments with reference to the accompanying drawings. Detailed implementation manners

[0034] In order to make the purpose, technical solutions and advantages of the present application more clear, the following further details the present application in combination with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0035] Embodiment 1

[0036] As Figure 1 shown, Embodiment 1 proposes a UPS battery temperature control structure, including a battery module, a thermoelectric coupling layer, and a heat insulation outer shell.

[0037] The battery module includes a plurality of battery units 1, and a composite phase change material 2 is filled between the battery units 1. The composite phase change material 2 is prepared by a melt blending method from lauric acid, stearic acid and graphene oxide. The mass ratio of graphene oxide is 5%-15%, the sheet thickness of graphene oxide ≤ 5nm, and the mass mixing ratio of lauric acid and stearic acid is 1:1 to 1:3.

[0038] The battery module is used to integrate multiple battery cells 1 to form the core energy storage unit of the UPS system, and realizes the functions of electric energy storage and release through series or parallel connection. The modular design of the battery module facilitates large-scale expansion and maintenance. The multiple battery cells 1 are arranged at uniform intervals, which can effectively disperse the heat distribution during charge and discharge and avoid local overheating. In high-temperature scenarios, the dispersed layout of the battery cells 1 in the module combined with the filling of the composite phase change material 2 can reduce the impact of heat accumulation on the overall performance; in low-temperature scenarios, the internal space design of the module allows uniform heat conduction of the semiconductor thermoelectric module 3 array to ensure that each battery cell 1 can obtain temperature compensation. In addition, the modular structure is compatible with various types such as lead-acid batteries and lithium batteries, and adapts to the capacity requirements of different UPS systems.

[0039] The battery cell 1, as the basic energy storage element of the UPS battery, is used to realize the charge and discharge functions through electrochemical reactions. Each battery cell 1 is independently encapsulated and physically isolated from adjacent cells, which can prevent chain reactions caused by thermal runaway or electrolyte leakage. In extreme temperature environments, the failure of a single battery cell 1 will not spread to the entire module, significantly improving the system safety. At the same time, the standardized size design of the battery cell 1 facilitates quick replacement and reduces the complexity of operation and maintenance.

[0040] The composite phase change material 2 (PCM) is filled in the gap between the battery cells 1 to absorb or release latent heat through solid-liquid phase change, buffering the sudden change in battery temperature. In a high-temperature environment, the composite phase change material 2 absorbs the heat generated by the battery through the phase change process from solid to liquid, delaying the battery temperature rise rate and avoiding the evaporation of the electrolyte or the decomposition of the SEI film of the lithium-ion battery caused by a sudden temperature rise; in a low-temperature environment, when the composite phase change material 2 solidifies from liquid to solid, it releases latent heat, slowing down the battery temperature drop and reducing the internal resistance growth rate, thereby maintaining the battery discharge capacity. In addition, the insulating property of the composite phase change material 2 can prevent the risk of short circuit between the battery cells 1. Lauric acid is used as the low-temperature phase change material, and the phase change temperature of lauric acid is about 44 °C (latent heat of fusion is about 180 J / g), which is used to provide the heat storage / release capacity in the medium and low temperature range. Stearic acid is used as the high-temperature phase change material, and the phase change temperature of stearic acid is about 69 °C (latent heat is about 200 J / g), which is used to expand the temperature control ability in the high-temperature range. By adjusting the ratio of lauric acid to stearic acid, the phase change temperature of the composite phase change material 2 can be flexibly adjusted to a higher range (such as 40 °C to 60 °C) to meet the high-temperature heat dissipation requirements. Graphene oxide has high thermal conductivity (in-plane thermal conductivity ~ 2000 W / (m·K)), which can improve the heat transfer efficiency of the composite phase change material 2. The nanosheets form a three-dimensional network, which can effectively inhibit the leakage of fatty acids and improve the cycle stability. In the mass ratio of graphene oxide, a lower limit of 5% can ensure the formation of a continuous thermal conduction network and avoid insufficient thermal conductivity; an upper limit of 15% can prevent excessive graphene oxide from hindering the movement of fatty acid molecular chains, resulting in a significant decrease in latent heat. Preferably, the mass ratio of graphene oxide is 10%. A 10% mass ratio of graphene oxide can ensure a high latent heat retention rate while ensuring a high thermal conductivity coefficient and a relatively long cycle life. In the mass ratio of lauric acid to stearic acid, a ratio of 1:1 is biased towards low-temperature phase change and is suitable for low-temperature UPS scenarios; a ratio of 1:3 is biased towards high-temperature phase change and is suitable for high-temperature industrial environments. Preferably, the mass ratio of lauric acid to stearic acid is 1:1.5. Under this mass ratio, the composite phase change material 2 can cover the typical UPS battery operating temperature range (-10 °C to 55 °C) and ensure a high latent heat value. Graphene oxide sheet thickness ≤ 5 nm can increase the specific surface area, strengthen the interfacial bonding with fatty acids, and reduce the interfacial thermal resistance; graphene oxide sheets with a thickness ≤ 5 nm can bend and fill the pores of the composite phase change material 2, improving the anti-leakage performance.

[0041] In this embodiment, the thermoelectric coupling layer surrounds the outside of the battery module. The thermoelectric coupling includes a semiconductor thermoelectric module 3 array and a heat conduction component. The semiconductor thermoelectric module 3 array is independently controlled in zones, and each semiconductor thermoelectric module 3 corresponds to a battery cell 1. The heat conduction component includes heat conduction fins 7 and a heat pipe 6. One end of the heat pipe 6 is connected to the hot end of the semiconductor thermoelectric module 3, and the other end extends to the outside of the heat insulation shell. The heat conduction fins 7 are located outside the heat insulation shell, and the heat conduction fins 7 are connected to the heat pipe 6.

[0042] The thermoelectric coupling layer is arranged around the battery module and is used to integrate the semiconductor thermoelectric module 3 (TEC) and the heat conduction component to achieve active regulation of the battery temperature. As the core of active temperature control, the thermoelectric coupling layer dynamically compensates for the heat buffering limit of the composite phase change material 2 through the cooling or heating function of the semiconductor thermoelectric module 3 array. For example, when the composite phase change material 2 is completely liquefied due to continuous high temperature, the semiconductor thermoelectric module 3 starts the cooling mode, and conducts the battery heat to the outside of the heat insulation shell through the heat conduction component; when the heat released by the solidification of the composite phase change material 2 is insufficient at low temperature, the semiconductor thermoelectric module 3 switches to the heating mode, and uses the redundant power of the UPS or the waste heat of the battery discharge to preheat the battery. The partition control design in the coupling layer allows for targeted regulation of local hot spots or cold areas within the module, thereby reducing overall energy consumption.

[0043] The semiconductor thermoelectric module 3 array is integrated in the thermoelectric coupling layer and is used to achieve two-way temperature control (cooling or heating) based on the Peltier effect. Each semiconductor thermoelectric module 3 is independently controlled, and the cooling or heating power of the corresponding area can be accurately adjusted according to the feedback data of the surface temperature sensor of the battery cell 1. For example, in the locally overheated area of the battery module, a forward current is passed through the semiconductor thermoelectric module 3, the cold end is close to the battery cell 1 to absorb heat, and the hot end dissipates heat to the outside through the heat conduction component; in the low-temperature area, a reverse current is passed through the semiconductor thermoelectric module 3, and the hot end is close to the battery cell 1 to release heat. Compared with the traditional resistance wire heating or compressor cooling solutions, the semiconductor thermoelectric module 3 array has the advantages of no mechanical moving parts, fast response speed (millisecond level), and high temperature control accuracy (±0.5 °C), and is especially suitable for scenarios with frequent instantaneous load fluctuations (such as data center UPS). In addition, the semiconductor thermoelectric module 3 array can generate electricity using the temperature difference between the hot and cold ends in the cooling mode, recover part of the energy to recharge the battery, and improve the system energy efficiency.

[0044] The heat conduction components (i.e., the heat pipe 6 and the heat conduction fins 7) are embedded in the thermoelectric coupling layer and are used to establish an efficient heat conduction path between the semiconductor thermoelectric module 3 and the heat insulation shell. The working fluid inside the heat pipe 6 quickly transfers the heat generated at the hot end of the semiconductor thermoelectric module 3 to the radiation coating 5 area outside the heat insulation shell through the evaporation-condensation cycle, avoiding heat accumulation in the coupling layer. The heat pipe 6 guides the heat on the semiconductor thermoelectric module 3 to the heat conduction fins 7 located outside the heat insulation shell. The heat conduction fins 7 increase the heat dissipation surface area and strengthen the heat exchange efficiency with the outside air, and then diffuse the heat guided by the heat pipe 6 to the heat conduction fins 7 into the outside air to achieve the heat dissipation effect.

[0045] In this embodiment, the heat insulation layer 4 is composed of silica aerogel and silicon carbide nanofibers. The mass fraction of the silicon carbide nanofibers is 5%-10%. The silicon carbide nanofibers are embedded in the silica aerogel matrix. The thickness of the heat insulation layer 4 is 3-8 mm. The radiation coating 5 is composed of titanium dioxide particles and polydimethylsiloxane. The mass proportion of the titanium dioxide particles is 60%-80%. The particle size range of the titanium dioxide particles is 200 nm-400 nm. The titanium dioxide particles are embedded in the polydimethylsiloxane matrix in a disordered stacking manner.

[0046] The heat insulation shell is coated outside the thermoelectric coupling layer to block the interference of the external environmental temperature on the battery module. The double-layer structure (heat insulation layer 4 + radiation coating 5) of the shell forms a passive thermal barrier.

[0047] The heat insulation layer 4, as the inner layer of the heat insulation shell, is used to reduce the heat exchange between the environment and the battery module through its low thermal conductivity characteristics. Silica aerogel has an ultra-low thermal conductivity and is used to provide an adiabatic core. Silicon carbide nanofibers form a three-dimensional skeleton to improve the compressive strength, and it has a high infrared reflectivity, which can reduce radiative heat transfer and make up for the high transmittance of aerogel to long-wave radiation. Among the mass fraction of silicon carbide nanofibers, the lower limit of 5% can ensure the formation of a continuous fiber network and significantly improve the mechanical strength; the upper limit of 10% can prevent the excessive fibers from blocking the pores of the aerogel and causing an increase in the thermal conductivity. Preferably, the mass fraction of the silicon carbide nanofibers is 8%. At this mass fraction, both high mechanical strength and low thermal conductivity can be ensured. Among the thickness of the heat insulation layer 4, the lower limit of 3 mm can ensure the basic heat insulation performance; the upper limit of 8 mm can control the volume and weight and avoid the bloating of the UPS device; high-efficiency heat insulation in a limited space can be achieved. The preferred thickness of the heat insulation layer 4 is 5 mm. At this thickness, the heat insulation layer 4 can ensure both heat insulation performance and lightweight.

[0048] The radiation coating 5, as the outer layer of the heat insulation shell, is used to achieve passive heat dissipation or heat preservation through its high reflectivity and high emissivity characteristics. Titanium dioxide particles have a high solar reflectivity and a high mid-infrared emissivity, which can achieve radiative cooling. The polydimethylsiloxane matrix has the functions of adapting to temperature deformation, avoiding coating cracking, resisting UV aging, and extending the outdoor service life. Among the mass proportion of titanium dioxide, the lower limit of 60% can ensure the formation of a continuous reflection network among the particles; the upper limit of 80% prevents the excessive titanium dioxide from causing coating embrittlement or a decrease in adhesion. Preferably, the mass proportion of titanium dioxide is 75%. At this mass proportion, both high reflectivity and good coating flexibility can be ensured. Among the particle size of titanium dioxide, the lower limit of 200 nm can effectively scatter visible light and improve the reflectivity; the upper limit of 400 nm can optimize the mid-infrared emissivity and enhance radiative heat dissipation. Preferably, the particle size of titanium dioxide is 300 nm. At this particle size, the balance between solar reflection and infrared reflection can be achieved, and the particle size uniformity is easy to control.

[0049] Example 2

[0050] As Figure 2 shown, Example 2 proposes a UPS battery temperature control method, including the following steps:

[0051] S100. Real-time monitor the battery temperature, ambient temperature and the phase change state of the composite phase change material;

[0052] The surface temperature of each unit in the battery module and the external ambient temperature are collected in real time through distributed temperature sensors (such as NTC thermistors). By real-time monitoring the battery temperature and ambient temperature, combined with the accurate determination of the phase change state of the composite phase change material, the system can dynamically perceive the change of the thermal load of the battery module and external environmental interference, providing multi-dimensional data support for subsequent mode decision-making, thus avoiding the response delay or misjudgment caused by single temperature threshold control in the traditional solution and significantly improving the temperature control reliability in extreme temperature scenarios.

[0053] S200. Dynamically select the pure composite phase change material buffering mode, the semiconductor thermoelectric module active temperature control mode or the hybrid mode according to the temperature threshold and the state of the composite phase change material.

[0054] Based on the monitoring data of S100, the optimal temperature control strategy is selected through the pre-set algorithm decision tree. Specifically, when the temperature of the battery module is within the temperature control range of the composite phase change material and the composite phase change material is not saturated, the composite phase change material buffering mode is adopted; when the temperature of the battery module changes too fast and exceeds the temperature control speed of the composite phase change material, the semiconductor thermoelectric module active temperature control mode is adopted; when the temperature of the battery module is close to the temperature control critical value of the composite phase change material and the composite phase change material is in the phase change transition state (such as partial liquefaction), the hybrid mode is adopted. In the hybrid mode, the semiconductor thermoelectric module only makes up the temperature difference when the buffering of the composite phase change material is insufficient. Based on the adaptive mode switching mechanism of real-time data and the state of the composite phase change material, the passive buffering ability of the composite phase change material is preferentially utilized to reduce energy consumption, and the semiconductor thermoelectric module is only activated for active compensation when the composite phase change material absorbs / releases heat to saturation, which can not only achieve zero additional energy consumption temperature control in mild environments, but also quickly stabilize the battery temperature in extreme temperatures, thus balancing energy efficiency and temperature control requirements.

[0055] S300. In the semiconductor thermoelectric module active temperature control mode, adjust the power of the semiconductor thermoelectric module based on the temperature difference and conduct heat in a directional manner through the heat conduction component.

[0056] According to the real-time temperature difference and its change rate, the current of the semiconductor thermoelectric module is dynamically adjusted using the PID algorithm, and heat is directionally exported or imported through heat pipes and fins. Real-time temperature difference = surface temperature of each unit in the battery module - target temperature. By dynamically adjusting the power of the semiconductor thermoelectric module using the PID algorithm and combining with the directional heat conduction path of the heat conduction component, the system can accurately offset the battery temperature fluctuations, and efficiently direct the heat to the radiation heat dissipation surface outside the heat insulation shell or reversely import it into the battery module, avoiding heat accumulation or cold penetration caused by chaotic heat dissipation paths. Thus, in high-temperature scenarios, the hot end temperature of the semiconductor thermoelectric module is reduced to improve the refrigeration efficiency, and in low-temperature scenarios, heat is concentrated to maintain the battery activity.

[0057] S400. Energy is recovered using the temperature difference between the hot and cold ends of the semiconductor thermoelectric module, and the generated electric energy is recharged to the battery.

[0058] In the refrigeration mode of the semiconductor thermoelectric module, when the temperature difference between the hot and cold ends ≥ 10 °C, the TEC is switched to the power generation mode, and the thermal energy is converted into electric energy using the Seebeck effect and recharged to the battery through a DC-DC converter. By converting the temperature difference between the hot and cold ends generated in the refrigeration mode into electric energy using the Seebeck effect of the semiconductor thermoelectric module and recharging it to the battery, the system forms an energy closed-loop of "temperature control - power generation - recharge", directly reducing the net energy consumption of the operation of the semiconductor thermoelectric module, while reducing the dependence on external power sources. Thus, part of the energy is recovered during the high-temperature heat dissipation process, further optimizing the system energy efficiency.

[0059] In this embodiment, the phase change state of the composite phase change material is determined in the following way:

[0060] When the battery temperature exceeds the phase change temperature of the composite phase change material and the duration exceeds the threshold, it is determined that the composite phase change material enters the liquid state;

[0061] When the battery temperature is lower than the phase change temperature of the composite phase change material and the impedance change rate exceeds the set value, it is determined that the composite phase change material returns to the solid state.

[0062] By introducing the dual criteria of time threshold and impedance change rate, the system can accurately identify the phase change process of the composite phase change material (such as partial liquefaction or complete solidification), avoiding mis-triggering caused by a single temperature criterion (such as misjudging instantaneous temperature fluctuations as phase changes), thus ensuring that when the heat absorption / heat release potential of the composite phase change material is close to saturation (such as the liquid proportion > 90% or the solid state impedance suddenly increases), it is timely switched to the active mode of the semiconductor thermoelectric module.

[0063] In this embodiment, the logic of the dynamic selection mode includes:

[0064] If the battery SOC < 20%, the active temperature control mode of the semiconductor thermoelectric module is disabled, and only rely on the passive heat dissipation or heat preservation of the composite phase change material buffer and radiation coating.

[0065] Through SOC priority control, when the battery power is insufficient, the power supply demand of the load is preferentially guaranteed, avoiding the active temperature control of the semiconductor thermoelectric module consuming the remaining power and causing the system to shut down in advance. At the same time, relying on the passive buffering of the composite phase change material and the heat insulation / dissipation characteristics of the shell to maintain basic thermal management, the reliability of the system in emergency scenarios is improved.

[0066] In this embodiment, in the hybrid mode, the composite phase change material is preferentially utilized to absorb or release latent heat, and the semiconductor thermoelectric module is started only after the phase change of the composite phase change material is saturated to make up the temperature control demand.

[0067] The power regulation of the semiconductor thermoelectric module adopts the PID algorithm, and the input parameters include the real-time temperature difference, the temperature difference change rate, and the battery load current.

[0068] Through the priority strategy of the composite phase change material buffer, the passive thermal management ability of the composite phase change material is maximally utilized, and the semiconductor thermoelectric module is started only when the phase change potential of the composite phase change material is exhausted (such as complete liquefaction or solidification) for supplementary temperature control, reducing the working duration and energy consumption of the semiconductor thermoelectric module, and achieving precise matching of energy efficiency and temperature control requirements.

[0069] By introducing multi-parameter PID control (temperature difference, temperature difference change rate, load current), the power of the semiconductor thermoelectric module is dynamically adjusted to match the real-time heat load change (such as the accelerated temperature rise caused by a sudden increase in load current). The response speed is increased by more than 50% compared with the traditional single temperature difference feedback algorithm, and overshoot and oscillation are suppressed, significantly extending the battery life.

[0070] In this embodiment, the specific steps of energy recovery are as follows:

[0071] When the temperature difference between the hot and cold ends of the semiconductor thermoelectric module is ≥10°C, the semiconductor thermoelectric module is switched to the power generation mode, and the output electric energy is charged back to the battery through the DC-DC converter.

[0072] By setting a temperature difference threshold to trigger energy recovery (≥10°C), it is ensured that power generation is started when there is a significant temperature difference in the semiconductor thermoelectric module (avoiding energy loss at low-efficiency temperature differences), and the DC-DC converter is combined to optimize the electric energy recovery efficiency (>85%), forming a sustainable closed-loop energy utilization chain.

[0073] In the accompanying drawings of this embodiment, the same or similar reference numerals correspond to the same or similar components; in the description of the present application, it should be understood that if there are terms such as "upper", "lower", "left", "right", etc. indicating the orientation or positional relationship, they are based on the orientation or positional relationship shown in the accompanying drawings. This is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the positional relationship in the accompanying drawings are only for illustrative purposes and cannot be construed as a limitation of this patent. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific circumstances.

[0074] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall be included within the protection scope of the present application.

Claims

1. A temperature control structure for a UPS battery, characterized in that, It includes a battery module, a thermoelectric coupling layer, and a heat-insulating housing; The battery module includes a plurality of battery cells (1), and a composite phase change material (2) is filled between the battery cells (1); The thermoelectric coupling layer surrounds the outside of the battery module, and the thermoelectric coupling includes an array of semiconductor thermoelectric modules (3) and a heat-conducting component; The heat-insulating housing is sleeved outside the thermoelectric coupling layer, and the heat-insulating housing includes a heat-insulating layer (4) and a radiation coating (5), and the heat-insulating layer (4) is located inside the radiation coating (5).

2. The UPS battery temperature control structure according to claim 1, wherein, The composite phase change material (2) is prepared by a melt blending method from lauric acid, stearic acid, and graphene oxide. The mass ratio of the graphene oxide is 5%-15%, the sheet thickness of the graphene oxide is ≤5 nm, and the mass mixing ratio of the lauric acid to the stearic acid is 1:1 to 1:

3.

3. The UPS battery temperature control structure according to claim 1, characterized in that, The array of semiconductor thermoelectric modules (3) is independently partition-controlled, and each semiconductor thermoelectric module (3) corresponds to a battery cell (1).

4. The UPS battery temperature control structure according to claim 1, characterized in that The heat-conducting component includes heat-conducting fins (7) and a heat pipe (6). One end of the heat pipe (6) is connected to the hot end of the semiconductor thermoelectric module (3), and the other end extends to the outside of the heat-insulating housing. The heat-conducting fins (7) are located outside the heat-insulating housing, and the heat-conducting fins (7) are connected to the heat pipe (6).

5. The UPS battery temperature control structure according to claim 1, wherein, The heat-insulating layer (4) is composed of silica aerogel and silicon carbide nanofibers. The mass fraction of the silicon carbide nanofibers is 5%-10%. The silicon carbide nanofibers are embedded in the silica aerogel matrix. The thickness of the heat-insulating layer (4) is 3-8 mm. The radiation coating (5) is composed of titanium dioxide particles and polydimethylsiloxane. The mass ratio of the titanium dioxide particles is 60%-80%. The particle size range of the titanium dioxide particles is 200 nm-400 nm. The titanium dioxide particles are embedded in the polydimethylsiloxane matrix in a disordered stacking manner.

6. The temperature control method of the UPS battery temperature control structure according to any one of claims 1-5 above, characterized in that, It includes the following steps: S100. Real-time monitor the battery temperature, the ambient temperature, and the phase change state of the composite phase change material; S200. Dynamically select a pure composite phase change material buffering mode, a semiconductor thermoelectric module active temperature control mode, or a hybrid mode according to the temperature threshold and the state of the composite phase change material; S300. In the semiconductor thermoelectric module active temperature control mode, adjust the power of the semiconductor thermoelectric module based on the temperature difference and conduct heat directionally through the heat-conducting component; S400. Recover energy using the temperature difference between the hot and cold ends of the semiconductor thermoelectric module, and recharge the generated electric energy to the battery.

7. The UPS battery temperature control method according to claim 6, wherein The phase change state of the composite phase change material is determined by the following method: When the battery temperature exceeds the phase change temperature of the composite phase change material and the duration exceeds the threshold, it is determined that the composite phase change material enters the liquid state; When the battery temperature is lower than the phase change temperature of the composite phase change material and the impedance change rate exceeds the set value, it is determined that the composite phase change material returns to the solid state.

8. The UPS battery temperature control method according to claim 6, characterized in that The logic of the dynamically selected mode includes: If the battery SOC < 20%, disable the semiconductor thermoelectric module active temperature control mode, and only rely on the composite phase change material buffering and the radiation coating for passive heat dissipation or heat preservation.

9. The UPS battery temperature control method according to claim 6, wherein, In the hybrid mode, preferentially utilize the latent heat absorption or release of the composite phase change material, and only start the semiconductor thermoelectric module to supplement the temperature control requirements after the composite phase change material reaches phase change saturation; The power regulation of the semiconductor thermoelectric module adopts the PID algorithm, and the input parameters include the real-time temperature difference, the temperature difference change rate, and the battery load current.

10. The UPS battery temperature control method according to claim 6, characterized in that, The specific steps for energy recovery are as follows: When the temperature difference between the hot and cold ends of the semiconductor thermoelectric module is ≥ 10 °C, the semiconductor thermoelectric module is switched to the power generation mode, and the output electric energy is recharged to the battery through the DC-DC converter.

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