Battery Thermal Management System and Method

Abstract

An exemplary embodiment of the present disclosure provides a battery system including one or more battery modules, one or more thermal conduits, and one or more thermoelectric coolers. Each of the one or more battery modules may include a plurality of battery cells. The one or more thermal conduits may be coupled to the one or more battery modules. The one or more thermoelectric coolers may be coupled to the one or more thermal conduits. The one or more thermal conduits may be configured to flow thermal energy from the one or more battery modules to the one or more thermoelectric coolers. The thermoelectric cooler may be configured to dissipate thermal energy received from the one or more battery modules via the one or more thermal conduits.

Description

[Technical field]

[0001] (CROSS REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of U.S. Provisional Application No. 63 / 321,926, filed March 21, 2022, and U.S. Provisional Application No. 63 / 399,781, filed August 22, 2022, which are incorporated by reference in their entireties as if fully set forth below.

[0002] (Technical field) Various embodiments of the present disclosure relate generally to batteries, and more particularly, to systems and methods for managing thermal energy in batteries. [Background technology]

[0003] The development of photovoltaic (PV) and battery technology has created a huge demand for clean energy. The non-dispatchability and poor grid connection of PV power has increased the need for on-grid energy storage. In recent years, the idea of ​​hybrid PV, which links storage to PV farms, has gained increasing interest. Many such applications focus on distinct approaches for PV and storage, typically grid-side connected as shown in Figure 1. Such strategies are driven by the need to achieve compact energy storage modules with associated batteries and thermal management. A typical energy storage approach is modular, including the use of containers for larger systems. Such modules are typically stacked to achieve larger utility-scale systems. Currently available high energy density batteries tend to use lithium chemistry, which requires precise thermal management to prevent the battery from overheating and causing a fire. These batteries also tend to suffer a significant reduction in lifetime if the battery temperature is not maintained within a narrow range.

[0004] As an alternative approach, several techniques have been explored that link photovoltaics and battery energy storage at the panel level. Although the benefits of such a link are well known, implementation is problematic and costly. A typical approach used to date is to use phase change materials (PCMs) to regulate the battery temperature to, for example, 40°C, even at higher ambient temperatures. Although such an approach is “passive”, it requires deep interconnections between the PCM and the individual batteries, which results in high costs and makes the battery packs larger and more expensive. More importantly, the PCMs used can only absorb a limited amount of energy before changing state and are unable to protect the batteries beyond that. For example, using a battery pack in a location where the minimum temperature is higher than the phase change temperature will disable the battery and shorten its lifespan. Similarly, to avoid degradation of the battery performance and lifespan, the battery temperature needs to be kept above a certain value, which cannot be achieved by PCMs. Finally, the need to design a method that can operate for 10 to 20 years without maintenance is a major challenge that cannot be met by conventional cooling strategies. Most designs, especially larger rated systems, use complex cooling strategies involving refrigerants and fans, all of which require costly on-site maintenance.

[0005] There is another major challenge to be addressed in the design of grid-connected energy storage systems. Lithium chemistry batteries, especially the Li-ion types and even Li-Fe-P batteries, can be overloaded with high currents due to failures inside individual cells. This can cause local overheating and thermal runaway, leading to explosive outgassing of the battery and adjacent cells. The trend to pack larger energy storage modules than 1MWh with 50,000 Li-Fe-P cells in a single module, or to pack as many as 100 such modules tightly on a single site, all to achieve higher energy / power density, creates a potential fire hazard that is destructive and difficult to control. With so many battery cells in a very dense and compact system, it is not surprising that an explosive outgassing of one battery can cause a chain reaction and cause destruction. This is a major issue in the automotive sector and in the grid energy storage systems sector.

[0006] Finally, battery packs must be closely managed to ensure that individual cells do not overheat and degrade in capacity or life. A typical battery string for automotive or grid storage applications may use 125-250 cells in series to achieve 400V or 800V DC at the battery pack level. Battery management systems are used to monitor the voltage and current levels of individual cells and track their proper operation. However, given the large number of cells, different temperature and operating profiles, and manufacturing tolerances between cells, it is very difficult to ensure that the loading and aging experienced by individual cells is uniform. Although it is possible in principle to manage the voltage across individual cells in a high voltage stack, this is expensive and rarely done. A 100kWh / 400V DC battery pack may have up to 40 such strings arranged in parallel. It may not be possible to control the current flow between parallel cells or cell stacks. To reduce the complexity of the mechanical structure and battery management systems, manufacturers often choose to connect many battery cells in parallel and then in series. Such configurations can lead to degraded cells being overloaded by current draw from other cells, increasing the risk of failure and fire. Each of these design decisions represents a trade-off between battery management complexity and battery performance, but each reduces the battery's lifetime and increases the risk of explosive gas release and fire. For example, the very common parallel connection of 10 cells can reduce the expected battery lifetime by up to 40%. Therefore, a different approach is needed to realize scalable grid-connected battery energy storage systems. Summary of the Invention

[0007] An exemplary embodiment of the present disclosure provides a battery system including one or more battery modules, one or more thermal conductions, and one or more thermoelectric coolers. Each of the one or more battery modules may include a plurality of battery cells. The one or more thermal conductions may be coupled to the one or more battery modules. The one or more thermoelectric coolers may be coupled to the one or more thermal conductions. The one or more thermal conductions may be configured to flow thermal energy from the one or more battery modules to the one or more thermoelectric coolers. The thermoelectric cooler may be configured to dissipate thermal energy received from the one or more battery modules via the one or more thermal conductions.

[0008] In any of the embodiments disclosed herein, each of the one or more battery modules may further include a heat transfer plate and a support structure. The heat transfer plate may have a first surface and a second surface. At least a first portion of the plurality of battery cells may be disposed adjacent to the first surface of the heat transfer plate. The support structure may be disposed in contact between the first portion of the plurality of battery cells and the first surface of the heat transfer plate. The support structure may be configured to assist in flowing thermal energy generated in the first portion of the battery cells to the heat transfer plate.

[0009] In any of the embodiments disclosed herein, a second portion of the plurality of battery cells may be disposed adjacent to the second surface of the heat transfer plate, and each of the one or more battery modules may further include a second support structure disposed in contact between the second portion of the plurality of battery cells and the second surface of the heat transfer plate, the second support structure being configured to flow thermal energy generated in the second portion of the battery cells to the heat transfer plate.

[0010] In any of the embodiments disclosed herein, the heat transfer plate may contain aluminum.

[0011] In any of the embodiments disclosed herein, the battery system may further comprise insulation surrounding at least a portion of the one or more battery modules.

[0012] In any of the embodiments disclosed herein, the insulation may be configured to inhibit a flow of thermal energy between the plurality of battery cells and an environment external to the battery system.

[0013] In any of the embodiments disclosed herein, the battery system may further include a housing defining an interior space that may contain the one or more battery modules, the one or more thermal paths, the one or more thermoelectric coolers, and the insulation.

[0014] In any of the embodiments disclosed herein, the insulator may have a thermal conductivity of 0.001 to 0.0025 W / (m·K).

[0015] In any of the embodiments disclosed herein, the insulation may include an insulating sleeve and a side panel.

[0016] In any of the embodiments disclosed herein, the side panel may have one or more cavities configured to receive the one or more thermal conduits.

[0017] In any of the embodiments disclosed herein, the one or more thermoelectric coolers may comprise a Peltier junction.

[0018] In any of the embodiments disclosed herein, the battery system may further include one or more heat sinks that may be coupled to corresponding ones of the one or more thermoelectric coolers.

[0019] In any of the embodiments disclosed herein, the battery system may further comprise a chamber defining a substantially hollow interior cavity. The chamber may comprise a first opening and a second opening. The first opening may receive a first heat sink of the one or more heat sinks. The second opening may be in fluid communication with an external environment.

[0020] In any of the embodiments disclosed herein, the second opening may be located proximate an end of the chamber.

[0021] In any of the embodiments disclosed herein, the chamber may further comprise a fan configured to generate an airflow through the internal cavity to exhaust thermal energy from the heat sink through the second opening to the external environment.

[0022] In any of the embodiments disclosed herein, the battery system may be configured to generate voltage levels ranging from 24 to 48 volts.

[0023] Another embodiment of the present disclosure provides a battery system including a heat transfer plate, a first plurality of battery cells, a support structure, a heat conduction path, and a thermoelectric cooler. The first plurality of battery cells may be disposed adjacent to a first surface of the heat transfer plate. The support structure may be disposed between the first surface of the heat transfer plate and the first plurality of battery cells, and the support structure may be configured to assist in transferring thermal energy generated in the first plurality of battery cells to the heat transfer plate. The heat conduction path may be coupled to the heat transfer plate. The thermoelectric cooler may be coupled to the heat conduction path. The heat conduction path may be configured to transfer thermal energy from the heat transfer plate to the thermoelectric cooler. The thermoelectric cooler may be configured to dissipate thermal energy generated in the plurality of battery cells and received at the thermoelectric cooler via the support structure, the heat transfer plate, and the heat conduction path.

[0024] In any of the embodiments disclosed herein, the battery system may further include a second plurality of battery cells and a second support structure. The second plurality of battery cells may be disposed adjacent to a second surface of the heat transfer plate. The second surface may be opposite the first surface. The second support structure may be disposed between the second surface of the heat transfer plate and the second plurality of battery cells. The second support structure may be configured to assist in transferring thermal energy generated in the second plurality of battery cells to the heat transfer plate.

[0025] These and other aspects of the present disclosure are described below in the Detailed Description of the Invention and in the accompanying drawings. Other aspects and features of the embodiments will become apparent to those skilled in the art upon review of the following description of certain exemplary embodiments in conjunction with the drawings. Although features of the present disclosure may be described in conjunction with certain embodiments and drawings, all embodiments of the present disclosure may include one or more of the features described herein. Furthermore, although one or more embodiments may be described as having certain advantageous features, one or more of such features may also be used with various embodiments described herein. Similarly, although exemplary embodiments may be described below as device, system, or method embodiments, it should be understood that such exemplary embodiments may be implemented in various devices, systems, and methods of the present disclosure. [Brief description of the drawings]

[0026] The following detailed description of certain embodiments of the present disclosure will be better understood when read in conjunction with the accompanying drawings. For the purpose of illustrating the present disclosure, certain embodiments are shown in the drawings. It should be understood, however, that the disclosure is not limited to the precise arrangements and instrumentalities of the embodiments shown in the drawings.

[0027] [Figure 1A]FIG. 1A illustrates an example hybrid solar / storage grid-tied diagram of an AC (FIG. 1A) system that may be used in some embodiments of the present disclosure. [Figure 1B] FIG. 1B illustrates an example hybrid solar / storage grid-tied diagram of a DC (FIG. 1B) system that may be used in some embodiments of the present disclosure.

[0028] [Diagram 2] FIG. 2 illustrates a high-level block diagram of an example microinverter including M 14S1P battery strings forming a pack, N photovoltaic (PV) solar panels with respective dc / dc converters, and an isolated dc / ac converter, used in accordance with some embodiments of the present disclosure.

[0029] [Diagram 3] FIG. 3 shows an exploded view of a battery system according to some embodiments of the present disclosure.

[0030] [Figure 4A] FIG. 4A shows an illustration of a battery module (FIG. 4A) according to some embodiments of the present disclosure. [Figure 4B] FIG. 4B shows an illustration of a battery pack (FIG. 4B) according to some embodiments of the present disclosure.

[0031] [Diagram 5] FIG. 5 illustrates a battery pack and vacuum panel case according to some embodiments of the present disclosure.

[0032] [Figure 6] FIG. 6 shows an illustration of a Peltier junction module thermal interface with a battery pack according to some embodiments of the present disclosure.

[0033] [Figure 7] FIG. 7 illustrates an exploded view of a vacuum insulated enclosure according to some embodiments of the present disclosure.

[0034] [Figure 8] FIG. 8 shows a close-up view of an insulating chamber according to some embodiments of the present disclosure.

[0035] [Figure 9] FIG. 9 shows an exploded view of a battery system according to some embodiments of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0036] In order to facilitate the understanding of the principles and features of the present disclosure, various exemplary embodiments are described below. The components, steps, and materials described below as constituting various elements of the embodiments disclosed herein are intended to be illustrative and not limiting. Many suitable components, steps, and materials that will perform the same or similar functions as the components, steps, and materials described herein are intended to be encompassed within the scope of the present disclosure. Such other components, steps, and materials not described herein include, but are not limited to, similar components or steps developed after the development of the embodiments disclosed herein.

[0037] As mentioned above, to achieve further integration of solar energy into the grid, there is a need to provide battery packs with long term storage, e.g., 3-6 hours, that can be coupled with PV panels to provide a scalable hybrid photovoltaic power system, or pure energy storage systems that directly connect to a bulk power system, such as an AC or DC grid. Of particular interest is the ability to provide long battery pack life in outdoor environments where the outside temperature ranges, e.g., from -20°C to +60°C, for extended periods of time. The present disclosure addresses the thermal management of such outdoor battery packs.

[0038] The embodiments disclosed herein can provide long periods of energy storage (e.g., 3-6 hours). For example, consider a 2.7 kWh battery pack with a nominal power rating of 500 W and a peak of 1 kW. This allows for 2.7-5.4 hours of energy storage, which can be used in conjunction with PV panels and the grid to provide a flexible, dispatchable generating grid resource. Such a pack can be built with 140 32700 LiFePO4 cells with a nominal 3.2 V and 6 Ah capacity. When operating at 500 W, the battery has a charge and discharge rate of C / 6, and at 1 kW it has a charge and discharge rate of C / 3. This is much lower than the charge and discharge rates often applied to lithium cells in other applications where the ability to operate at high C-rates is typically of interest.

[0039] Low C-rate operation of batteries can have a significant impact on the thermal design of the entire pack. Taking a typical LiFePO4 cell as an example, we can see that at C / 3 operating conditions, the dissipation of each battery is roughly 0.045W, and at C / 6 rate it is about 0.011W. This corresponds to a maximum total dissipation of about 5.6W that needs to be managed for the entire pack under nominal conditions. At higher 3C levels, such as those found in some automotive applications, the power dissipation per battery can be over 3.6W per cell and 500W at the pack level, meaning that the thermal management problem becomes more challenging.

[0040] The approximate mechanical dimensions of the typical 2.7 kWh battery pack mentioned above are approximately 20 inches by 18 inches by 3 inches. The entire battery module may be placed in an external environment and exposed to ambient temperatures that vary widely, for example, from -20°C to +60°C. With a large surface area available, approximately 720 square inches, heat flow between the battery and the environment can be a much bigger problem than dealing with heat loss from the battery. If an aluminum battery housing has a typical thermal resistance of 1 W / °K, and there is a 40°C temperature difference between the environment and the desired battery temperature, then it can be seen that a heat flow of 80 W must be managed to maintain the battery temperature and achieve a long life. This is in contrast to the 5.6 W of heat to be managed inside the battery.

[0041] Therefore, rather than transferring heat from the battery to the environment, it may become more important to prevent heat from the environment from being transferred to the battery. It is desirable to maintain the battery at an optimal temperature and manage the individual cells safely to maximize battery life and maintain that condition for a long period of time. Once the "thermal isolation" of the battery pack is achieved, it is also desirable to be able to safely regulate the temperature of the battery pack while managing the internal losses that occur in the battery. This significantly changes the thermal design problem.

[0042] Furthermore, to minimize the risk of thermal runaway and fire, it is desirable that batteries cannot dump energy into degraded cells, causing them to overheat and catch fire. For this reason, it is recommended that battery cells not be placed in parallel. Furthermore, it is desirable that batteries are not arranged in such a way that if an individual battery experiences an explosive outgassing, it can cause thermal runaway in adjacent cells. It is therefore desirable that batteries are arranged in such a way that any explosion that does occur is directed away from the other batteries. Furthermore, at the system level, it is desirable that battery modules are located far enough away from other packs that any fire that does occur is limited to a single battery pack and cannot propagate.

[0043] Additionally, it may be desirable to reduce the battery stack to a lower voltage (e.g., 48V for 14 series connected cells) with fewer series connected cells to manage the battery life and make the battery pack touch-safe. It may also be desirable to not connect battery cells in parallel to avoid battery life degradation. Individual series strings (i.e., 14S1P configuration) can be monitored for degradation of any single cell, and current to that string can be throttled if such degradation is detected by the string stabilization circuit. By configuring the battery stack (i.e., 10×14SP1, 14S10P (whole pack)) and Battery Management System (BMS) system as described herein (and shown in FIG. 2), the life of the battery module can be maximized. However, managing the thermal environment of the battery under all possible operating conditions remains a significant challenge. The embodiments disclosed below address this challenge.

[0044] As shown in FIG. 3, an exemplary embodiment of the present disclosure provides a battery system including one or more battery modules 105, one or more thermal conduction paths 115, and one or more thermoelectric coolers 120. As shown in FIG. 4A, each of the one or more battery modules 105 may include a plurality of batteries 110. The batteries may be many different batteries known in the art, including but not limited to lithium ion batteries. As shown in FIG. 4A, each of the one or more battery modules 105 may further include a support structure 130 that may mechanically interlock the batteries within the battery module. The support structure 130 may be made of many different materials. In some embodiments, the support structure 130 may be made of a thermal insulating material that may help direct thermal energy from the batteries 110 to the thermal transfer plate 125. In some embodiments, the support structure 130 may substantially surround the batteries 110. For example, as shown in FIG. 4A, the support structure 130 may have a honeycomb shape for supporting the batteries 110.

[0045] As shown in FIG. 4B, a heat transfer plate 125 may be disposed between adjacent battery modules 105. The heat transfer plate may be made of many different thermally conductive materials known in the art, including, but not limited to, aluminum or other metals. The heat transfer plate 125 may have a first side 126 and a second side 127. The battery in the first battery module may be disposed adjacent to the first side of the heat transfer plate, for example, with a support structure 130 between the battery 110 and the first side of the heat transfer plate 125, and the battery in the second battery module may be disposed adjacent to the second side of the heat transfer plate, for example, with another support structure 130 between the battery 110 and the second side of the heat transfer plate 125.

[0046] 4B, one or more thermal conduction paths 115 may be coupled to one or more battery modules 105, for example, via a thermal transfer plate 125. Additionally, one or more thermoelectric coolers 120 may be coupled to one or more thermal conduction paths 115. Thus, heat generated in the battery 110 may flow through the support structure 130 to the thermal transfer plate 125 and then through the thermal conduction paths 115 to the thermoelectric cooler 120. The thermoelectric cooler 120, for example, comprised of a Peltier junction, may dissipate thermal energy to control the temperature of the battery system.

[0047] As shown in FIG. 5, FIG. 7, and FIG. 9, the battery system may further include an insulation body 135 surrounding at least a portion of the one or more battery modules 105. The insulation body 135 may be configured to inhibit the flow of thermal energy between the plurality of batteries and the external environment of the battery system. Thus, the insulation body 135 may serve to prevent heat from the external environment from reaching the battery 110 and affecting its temperature. The insulation body 135 may also serve to retain heat in the battery 110, for example, when the temperature of the external environment is low. In some embodiments, the insulation body may include an insulation sleeve 136 and a side panel 137 that combine to substantially surround the battery module. The insulation body 135 (including the insulation sleeve 136 and the side panel 137) may be made of many different insulating materials known in the art, including, but not limited to, rigid foam polyurethane panels, vacuum panels, and the like. Depending on the material of the insulation body 135, the insulation body 135 may have many different thermal conductivities ranging from 0.001 to 0.0025 W / (m·K).

[0048] 5, the shroud 137 may have one or more cavities 138 configured to receive the thermal conduits 115. The cavities 138 and the thermal conduits 115 protruding therethrough may thus provide a path for transferring thermal energy between the battery 110 within the insulation 135 and the exterior of the insulation 135.

[0049] 7, the battery system may further include an enclosure 140 (e.g., housing) defining an interior space 141. The enclosure may house other components of the battery system. The interior space 141 may house one or more battery modules 105, one or more thermal conduits 115, one or more thermoelectric coolers 120, and a thermal insulator 135 (as well as other components of the battery system).

[0050] 6, the battery system may further include one or more heat sinks 150. The heat sinks 150 may be coupled to corresponding thermoelectric coolers 120. The heat sinks may receive thermal energy from the thermoelectric coolers and dissipate the thermal energy. The heat sinks may be any of a number of heat sinks known in the art.

[0051] As shown in FIG. 6, the battery system may further include a chamber 155 defining a substantially hollow interior cavity. The chamber 155 may include multiple openings 156, 157. For example, the chamber may include a first opening 156 to receive a first heat sink. As shown, the chamber 155 may include additional openings to receive additional heat sinks. The chamber may further include a second opening in fluid communication with an external environment (e.g., an area external to the insulating sleeve and shroud). In some embodiments, the second opening may be located proximate an end of the chamber. In some embodiments, the chamber may have multiple openings (e.g., at each end of the chamber) in fluid communication with the external environment. As also shown in FIG. 6, the chamber 155 may further include a fan 158 configured to generate an airflow through the interior cavity of the chamber to exhaust thermal energy from the heat sink through the second opening 157 to the external environment. Using a chamber 155 with openings at both ends may increase thermal insulation between the external environment and the battery. EXAMPLES

[0052] Specific embodiments are disclosed below as examples, however, these embodiments should not be read as limiting the scope of the disclosure.

[0053] Disclosed below is a 2.7 kWh (10x14S1P) battery pack as shown in Figure 3, including an active thermal management system that can be used to cool or heat the battery module as needed. There are several important features of this design. Given the low losses of a single battery cell when operated below C / 3 (max 45mW), each battery can be bonded to a common aluminum plate with a reasonable thermal resistance. Even with a high thermal resistance of 10°C / W, the temperature difference between the plate and the battery is less than 0.5°C, facilitating the design of an active thermal management system. By constructing a honeycomb structure of the type shown in Figure 4A, the battery cells can be mechanically fixed to create a series stack of 14 batteries that constitute a building block. This building block can be multiple (e.g., 10 building blocks are used in the exemplary design) to achieve the desired kWh. More specifically, each honeycomb can be in turn fixed to an aluminum plate that provides both the mechanical fixation and an isothermal surface that fixes the temperature of all attached batteries. In the design shown in FIG. 4B, a total of six plates are used to secure all 140 cells used to form the 2.7 kWh battery pack.

[0054] The entire battery pack / module can be encapsulated in a vacuum panel with high thermal resistance configured as a shrouded insulating sleeve, one embodiment of which is shown in Figure 5. The "isothermal" aluminum plate is connected to one or more "heat conduits" (also called "thermal conduits") that provide a path for heat flow between the battery pack and its exterior, as shown in Figure 4B. Other paths for heat flow can be thermally insulated as much as possible (e.g., through the use of vacuum panels).

[0055] As mentioned above, the main challenge is the desire to keep the battery pack cool, say to a temperature of 30°C, when the environment is 60°C. Analysis of a cavity of similar volume shows that the tested vacuum packs had a heat flow of approximately 5W between the environment and the "pack". This suggests that even in the absence of battery losses, it would be desirable to continuously remove 5W of thermal power from the pack space. Furthermore, when the battery is in operation (i.e. charging and discharging), it would be desirable to continuously remove 10.6W. Approaches where the phase change material passively receives heat have a limited ability to manage the battery temperature under all operating conditions, as there is a finite amount of energy it can absorb.

[0056] Unlike passive thermal management approaches, Peltier junctions can be used as thermoelectric coolers placed on "heat conduit" pads to remove heat from an insulated battery pack, as shown in Figure 6. Applying a controlled DC voltage to the Peltier junctions cools the surface to which they are attached, transferring heat from the surface requiring thermal management to the other surface.

[0057] The battery pack, enclosed in a vacuum panel, can be completely contained within a sealed cabinet that is the housing for the entire device, as shown in Figure 7. The outer heat sink of the Peltier junction can be completely enclosed in an insulated cavity (shown in red in Figure 8). Under nominal conditions, when the battery pack is within the desired temperature range, heat exchange occurs only between the battery pack and the inside of the device case, mostly through the vacuum panel (estimated at 30°C temperature difference and maximum battery loss of 5-10 W). When the battery temperature rises and regulation is required, the Peltier can be turned on and a heat exchange mechanism such as a long-life small fan or a pulsating diaphragm device (e.g., speaker or Synjet) can be used to cool the Peltier junction and transfer heat to the inside of the device housing by convection. This provides a low thermal resistance when the airflow is activated and a high thermal resistance when it is off. This feature allows the battery pack to be maintained within the desired temperature range without continuous and sustained power loss.

[0058] While Peltier junctions can be used to both heat and cool the battery pack, resistive heating of about 5-10 W can also be used to heat the pack, minimizing the use of convection cooling mechanisms. If the external environment is cold, heat flow can be countered between the internal heat generated by the battery and the resistive heating element. It should be noted that heat can be transferred inside the device housing, and air can exist between the battery housing and the exterior of the device housing. This air barrier can provide high thermal resistance and further limit heat loss / gain by the battery pack.

[0059] A key factor in the overall design and operation of the exemplary active thermal management system is the impact that the thermal inertia of the battery module has on the system. The battery and its components represent approximately 70 pounds of weight and a large thermal mass. In a properly insulated environment, the module can stay warm or cold for a day or more without external heating or cooling. Thus, the battery pack can be pre-cooled or pre-heated to optimize cost and temperature deviation based on solar, air temperature, and load forecasts. Passive cooling systems cannot provide this level of flexibility and performance. However, typical active thermal management systems cannot provide long life and maintenance-free operation. The proposed approach can achieve both.

[0060] Additionally, power conversion elements including PV panel conditioners, battery string insulators, and DC / AC inverters are in place so that the hybrid photovoltaic / storage system can operate in a grid-tied configuration (see Figure 9). Assuming a typical 97% efficiency for power conversion, the total losses are about 30W for 1kW input / output and about 15W for 500W. A significant portion of this loss can be directly associated with the equipment housing, while it can be assumed that roughly 10W can be associated with the air. Including the losses of the battery, synjet / fan, battery management system ("BMS"), and power converter, it can be estimated that about 25W of losses are added inside the equipment housing. These losses can be exchanged with the external environment. Considering that the surface area of ​​the equipment housing (including the power converter and battery pack) is over 800 square inches, an effective thermal resistance estimated at about 0.2°C / W is seen, and the loss of 25W inside the cabinet will result in a temperature difference of about 5°C between the air outside the cabinet and the air inside. Also, the presence of a synjet / fan can be set to mix the air to equalize the temperature inside the cabinet. The only wires running in and out of the equipment housing are those for connection to the PV panel or grid; otherwise the equipment housing can be sealed.

[0061] It is to be understood that the embodiments and claims disclosed herein are not limited in their application to the details of construction and arrangement of the components described herein and illustrated in the drawings. Rather, the specification and drawings provide examples of possible embodiments. The embodiments and claims disclosed herein are capable of further embodiments and can be practiced and carried out in various ways. It is also to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be construed as limiting the scope of the claims.

[0062] As such, those skilled in the art will appreciate that the conception underlying the present application and claims may be readily utilized as a basis for the designing of other structures, methods and systems for carrying out the purposes of the embodiments and claims presented herein, and it is important that the claims be regarded as including such equivalent constructions.

[0063] Furthermore, the purpose of the Abstract is to enable the U.S. Patent and Trademark Office and the general public, including those not familiar with patent and legal terminology and phraseology, to quickly grasp the content and gist of the technical disclosure of the application upon a single reading. The Abstract does not define the scope of the claims of the application, nor does it limit the scope of the claims in any way.

Claims

1. A battery module, A heat transfer plate having a first surface and a second surface, A first portion of a battery cell arranged adjacent to the first surface of the heat transfer plate, The system comprises a first support structure disposed between the first surface of the heat transfer plate and the first portion of the battery cell, The first support structure is configured to assist in guiding the thermal energy generated in the first portion of the battery cell to the heat transfer plate, and includes a battery module. A heat conductor connected to the aforementioned battery module, A thermoelectric cooler connected to the aforementioned heat conduction path, It is equipped with, The heat conduction path is configured to transfer thermal energy from the battery module to the thermoelectric cooler. A battery system in which the thermoelectric cooler is configured to dissipate the thermal energy generated by the battery module.

2. The battery module further comprises a second support structure positioned in contact between a second portion of the battery cell, which is positioned adjacent to the second surface of the heat transfer plate, and the second surface of the heat transfer plate, The battery system according to claim 1, wherein the second support structure is configured to transfer thermal energy generated in the second portion of the battery cell to the heat transfer plate.

3. The battery system according to claim 1, wherein the heat transfer plate contains aluminum.

4. The battery system according to any one of claims 1 to 3, further comprising an insulating body surrounding at least a portion of the battery module.

5. The battery system according to claim 4, wherein the insulating material is configured to suppress the flow of thermal energy between the battery cell and the external environment of the battery system.

6. One or more battery modules, each of the battery modules is A heat transfer plate having a first surface and a second surface, A first portion of a battery cell arranged adjacent to the first surface of the heat transfer plate, The system comprises a first support structure disposed between the first surface of the heat transfer plate and the first portion of the battery cell, The first support structure is configured to assist in guiding the thermal energy generated in the first portion of the battery cell to the heat transfer plate, and comprises one or more battery modules. An insulating material surrounding at least a portion of the aforementioned battery module, One or more thermal conductors connected to one or more of the aforementioned battery modules, One or more thermoelectric coolers connected to one or more of the aforementioned heat conductions, The device comprises one or more of the aforementioned battery modules, one or more of the aforementioned heat conductions, one or more of the aforementioned thermoelectric coolers, and a housing that defines an internal space including the aforementioned heat insulating body. One or more of the aforementioned heat conductions are configured to pass thermal energy from one or more of the battery modules to one or more of the aforementioned thermoelectric coolers. One or more of the thermoelectric coolers are configured to dissipate the heat energy generated by one or more of the battery modules. A battery system in which the insulating material is configured to suppress the flow of thermal energy between the first portion of the battery cell and the external environment of the battery system.

7. The battery system according to claim 6, wherein the insulating material includes a vacuum panel having a thermal conductivity of 0.001 to 0.0025 W / (m·K).

8. The battery system according to claim 6, wherein the internal space of the housing includes the battery module, the heat conduction path, the thermoelectric cooler, and the heat insulating body, respectively.

9. The battery system according to claim 6, wherein the heat insulating body comprises a heat insulating sleeve and a side plate.

10. The battery system according to claim 9, wherein the side plate has one or more voids configured to receive one or more of the heat conductions.

11. The battery system according to claim 6, wherein one or more of the thermoelectric coolers comprises a Peltier junction.

12. Further comprising one or more heat sinks, The battery system according to any one of claims 6 to 11, wherein each of the heat sinks is coupled to a corresponding one of the thermoelectric coolers.

13. It further comprises a chamber that defines a substantially hollow internal cavity, The chamber in question is One or more heat sink openings, each of which has one or more heat sink openings that receive one of the corresponding heat sinks, A second opening that communicates fluidly with the external environment, The battery system according to claim 12, comprising the following:

14. The battery system according to claim 13, wherein the second opening is located in close proximity to the end of the chamber.

15. The battery system according to claim 13, wherein the chamber further comprises a fan configured to generate airflow through the internal cavity and discharge thermal energy from one or more of the heat sinks through the second opening to the external environment.

16. A battery system according to any one of claims 6 to 11, configured to generate a voltage level in the range of 24 to 48 volts.

17. Each of the battery modules is A second portion of a battery cell is positioned adjacent to the second surface of the heat transfer plate, which is on the opposite side of the first surface of the heat transfer plate, The present invention further comprises a second support structure disposed between the second surface of the heat transfer plate and the second portion of the battery cell, The battery system according to any one of claims 6 to 11, wherein the second support structure is configured to assist in guiding the thermal energy generated in the second portion of the battery cell to the heat transfer plate.

18. The battery system according to any one of claims 6 to 11, wherein the heat transfer plate contains aluminum.

19. The battery system according to any one of claims 6 to 11, wherein the heat insulating body comprises a heat insulating sleeve and at least one side plate.

20. The battery system according to any one of claims 6 to 11, wherein each of the thermoelectric coolers comprises a Peltier junction.

21. It further comprises a chamber that defines a substantially hollow internal cavity, The chamber in question is One or more heat sink openings, each of which has one or more heat sink openings that receive one of the corresponding heat sinks, A second opening that communicates fluidly with the external environment, The battery system according to claim 12, comprising the following:

22. The battery system according to claim 21, wherein the second opening is located in close proximity to the end of the chamber.

23. The battery system according to claim 21, wherein the chamber further comprises a fan configured to generate airflow through the internal cavity and discharge thermal energy from one or more of the heat sinks through the second opening to the external environment.

24. A battery system according to any one of claims 6 to 11, which provides 5.4 hours of energy storage by a 2.7 kWh battery system with a nominal power of 500 W and a peak power of 2 kW.

25. The battery system according to any one of claims 6 to 11, wherein the battery cell comprises various chemical systems including lithium ions and / or lithium iron phosphate.

26. The battery system according to any one of claims 6 to 11, wherein electronic hardware for battery management, thermal monitoring and control, and charge / discharge control is contained within the housing.

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