Solar energy storage and heat storage dual-energy storage method and system

Abstract

The invention discloses a solar power storage and heat storage dual-energy storage method and system, and relates to the technical field of solar photovoltaic and lithium battery energy storage cooperative power supply. Reasonable control over charging and heating of the battery module and control over the heat preservation or heat dissipation operation mode of the battery module can be achieved only through comprehensive interpretation of related conditions such as the temperature of a built-in temperature sensor of the lithium battery module and the output voltage of a photovoltaic module, and therefore the dual-energy-storage effect of charging and heating is achieved at the photovoltaic power generation peak. The problems that in the prior art, a solar power supply system abandons power in the power generation peak period under the condition of no mains supply, a lithium battery module has power and cannot be used in the low-temperature environment at night, or power supply time is shortened due to the fact that precious stored power is consumed for heating are solved. The beneficial effects of fully utilizing the photovoltaic power generation energy at the power generation peak and utilizing the green energy to the greatest extent are achieved.

Description

Technical Field

[0001] The present application relates to the field of solar photovoltaic and lithium battery energy storage collaborative power supply technology, specifically a dual energy storage method and system for solar power storage and heat storage. Background Art

[0002] At present, many communication base stations built in remote mountainous areas have no power supply conditions. The use of solar energy and lithium battery energy storage to jointly power supply can solve the problem of continuous power supply of communication base stations. Due to the timeliness of solar energy, energy storage batteries need to be charged and discharged every day to ensure the continuous operation of base stations. Therefore, lithium battery modules are the first choice for such base stations and have a service life of more than 3 years. However, lithium batteries are usually required to operate normally above 0°C during application. Temperatures below this will cause a decrease in discharge capacity and even lithium precipitation, leading to irreversible damage to the battery. The usual solution is to build a heating device into the lithium battery module to heat the battery module to above 0°C in a low temperature environment to ensure the normal discharge and use of the battery module. However, low temperature environments are usually at night without light. Battery heating wastes precious energy storage and greatly shortens the normal power supply time. There are also solutions that use immersion liquid cooling, placing the energy storage battery in a heat-insulating liquid cooling jacket, using solar energy to heat the liquid cooling jacket to heat the battery, and then using a circulating pump to guide the heat transfer fluid to the heat sink for heat dissipation in a high-temperature environment. However, this solution is complex, costly, difficult to install and maintain, and there are also problems such as leakage of heat transfer fluid that pollutes the environment. Some existing solutions mostly start heating the battery module when the battery module temperature is detected to be too low. For example, the patent document with the authorization announcement number CN215266459U discloses a solution disclosed by a battery pack and a photovoltaic tracking bracket, which monitors the external ambient temperature of the lithium battery pack in real time. When the protection board detects that the external ambient temperature of the lithium battery pack is lower than the set charge and discharge allowable temperature value, the internal heating control circuit starts the heating film to start heating. This type of solution discharges and keeps warm when the battery temperature is already low and the charge and discharge performance is reduced, which itself affects the battery life. Moreover, if the battery is still loaded at this time, it cannot guarantee that the heating module can obtain the guarantee of heating power, which also wastes solar energy. Summary of the invention

[0003] In view of the shortcomings of the prior art, the present application provides a dual energy storage method and system for solar power storage and heat storage to solve the problems of power abandonment during peak hours of solar power generation in the absence of city power in the prior art, and the additional power consumption of batteries in low temperature environments to heat themselves to maintain continuous power supply to equipment, resulting in shortened power supply time or damage to batteries due to low temperature power supply.

[0004] To achieve the above objectives, this application is implemented through the following technical solutions: A dual energy storage method for solar energy storage of electricity and heat: Use the following steps to turn on power storage: When the line voltage output by the photovoltaic module is greater than the charging start voltage of the battery module, the charging function of the battery module is turned on; Use the following steps to turn on thermal storage: S11 records the temperature change curve of the built-in temperature sensor of the battery module in the last 24 hours, and takes the minimum value as t1; S12 calculates the heating temperature target setting value t0 of the battery electric heating module according to the calculation frequency, t0=T-t1, where T is a heating temperature constant, the heating temperature constant has a value range of 35°C±3°C, and the calculation frequency has a value range of 0.6 times / hour to 12 times / hour; S13 compares the current temperature of the battery module with the heating temperature target setting value t0, and when t0 is greater than the current temperature of the battery module and the line voltage output by the photovoltaic module is greater than the charging rated voltage of the battery module, turns on the battery electric heating module; Use the following steps to switch the insulation and heat dissipation modes of the battery module: S21 determines the working mode of the insulation cover of the battery module according to the operation status of the battery electric heating module in the last 24 hours: if the battery electric heating module has been started, the opening and closing mechanism is controlled to close the insulation cover, and the insulation cover operates in the insulation mode; if the battery electric heating module has not been started, the opening and closing mechanism is controlled to open the insulation cover, and the insulation cover operates in the heat dissipation mode.

[0005] Preferably, the heating temperature constant is 35°C.

[0006] Preferably, the calculation frequency is once per hour.

[0007] Based on the same inventive concept, the present application also discloses a dual energy storage system for solar energy electricity storage and heat storage, including a photovoltaic component, a voltage conversion module, and a battery module. The photovoltaic component charges the battery module through the voltage conversion module. The battery module includes an inner shell, a battery cell group, a battery management system and a battery electric heating module. The battery management system obtains the charge and discharge status of the battery, the battery power and the line voltage output by the photovoltaic component. It also includes a heating control device, an ambient temperature collection device, an insulation sleeve, an insulation sleeve cover arranged oppositely, and an opening and closing mechanism. The insulation sleeve is sleeved on the outside of the battery module and forms an interval cavity therebetween. The insulation sleeve covers are respectively arranged at the opposite openings of the insulation sleeve and are controlled by the opening and closing mechanism. The opening and closing mechanism uses the aforementioned solar energy dual energy storage method to close or open the insulation sleeve cover and the insulation sleeve. The heating control device uses the aforementioned solar energy dual energy storage method to open the battery electric heating module.

[0008] Preferably, the opening and closing mechanism uses an electrically automatically controlled opening and closing mechanism.

[0009] Preferably, the electrically automatically controlled opening and closing mechanism includes a motor, a pull rod, a pull rod, a door panel, and a door panel axis fixing block. The motor is fixedly installed at the inner center of the insulation cover. The center of the pull rod is fixed on the motor shaft and rotates around the motor in a plane parallel to the insulation cover. The door panel is fixed in the door panel axis fixing block through the door panel axis at its edge. The door panel rotates around the door panel axis. The door panel axis fixing block is fixed at a position corresponding to the edge of the insulation cover and the inner wall of the insulation cover. One end of the pull rod is fixed to the far end of the pull rod, and the other end is fixed to the far end of the door panel axis. When the motor rotates, it drives the door panel to close or open the insulation cover and the insulation cover.

[0010] Preferably, the thermal insulation sleeve comprises an inner thermal insulation layer, and the interior of the thermal insulation layer is filled with phase change material.

[0011] Compared with the prior art, the present solution has the following beneficial effects: the present application uses a control system to comprehensively judge and control the heating module of the battery module itself to heat and store heat for the battery according to the current ambient temperature, the night temperature before the current time, the current capacity of the battery, etc., thereby forming a dual energy storage mode of electricity storage and energy storage, and then uses the insulation cover of the battery module to automatically switch the insulation and heat dissipation modes using an intelligent control method, making full use of the "abandoned electricity" during the peak power generation period to achieve heat storage, maximizing the use of green energy, and realizing the dual energy storage of electricity and heat storage of the photovoltaic system during the peak power generation period. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a three-dimensional connection diagram of an embodiment of a dual energy storage system for solar power and heat storage of the present application; Figure 2 This is a schematic internal side view of an opening and closing mechanism of an embodiment of the thermal insulation cover of the present application in a ventilation state; Figure 3 This is a schematic internal side view of an opening and closing mechanism of an embodiment of the thermal insulation cover of the present application in a sealed state; Figure 4 This is a schematic internal side view of the opening and closing mechanism of an embodiment of the thermal insulation cover of the present application in a process state; Among them, 1-photovoltaic component, 2-voltage conversion module, 3-insulation sleeve, 4-battery module, 5-hood, 6-baffle, 71-motor, 72-pull bar, 73-pull rod, 74-door panel, 741-door panel shaft, 75-door panel shaft fixing block. DETAILED DESCRIPTION

[0013] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0014] This embodiment provides a technical solution: This solution discloses a dual energy storage method of solar energy storage and heat storage, Use the following steps to turn on power storage: When the line voltage output by the photovoltaic module 1 is greater than the charging start voltage of the battery module 4, the charging function of the battery module is turned on. At this time, the power generation power of the photovoltaic module 1 is greater than the equipment load power but is not enough to charge the battery module 4 at full power; when the line voltage is greater than the rated charging voltage of the battery module 4, the charging current can reach the maximum current limit value. At this time, the power generation power of the photovoltaic module 1 is greater than or equal to the sum of the equipment power and the power required for full power charging of the battery module 4; Use the following steps to turn on thermal storage: S11 records the temperature change curve of the built-in temperature sensor of the battery module 4 in the last 24 hours. The curve covers the process of heating and cooling of the battery module. The minimum value is t1 and the maximum value is t2. Among them, t1 is the lowest temperature of the battery module 4 after sufficient heat dissipation at night, usually the temperature of the battery module 4 in the early morning, and t2 is the highest temperature reached by heating or natural heating during the day, usually the temperature of the battery module 4 in the afternoon; S12 confirms the heating temperature target value t0 of the lithium battery module 4. Since the normal operating temperature range of the lithium battery module 4 is 0℃~40℃, and the higher the temperature, the greater the activity and the stronger the discharge capacity, and the temperature curve during the heat release process is basically the same, the heating temperature target setting value t0 of the battery electric heating module can be calculated according to the calculation frequency, and t0 is calculated using the simplified formula t0=T-t1, where T is the heating temperature constant, and the heating temperature constant has a value range of 35℃±3℃, and the calculation frequency has a value range of 0.6 times / hour to 12 times / hour; in this embodiment, the heating temperature constant is 35℃, which is the temperature midline of the upper limit of summer temperature in most areas, which is more appropriate, and the calculation frequency is once per hour.

[0015] S13 compares the current temperature of the battery module with the heating temperature target setting value t0. When t0 is greater than the current temperature of the battery module and the line voltage output by the photovoltaic module 1 is greater than the rated charging voltage of the battery module 4, the battery electric heating module is turned on. At this time, the power generation capacity of the photovoltaic module 1 is higher than the actual power consumption of the equipment and the power demand of the battery charging. The excess electric energy is wasted as abandoned power in the traditional system of the prior art. In this system, it will be converted into thermal energy of the battery module for utilization and storage. If the above conditions are not met, the battery heating module will not be turned on, that is, the heat storage process uses the excess power generation capacity of the photovoltaic module. In the sunny scene during the day, there is sufficient solar energy and abundant electricity. According to the design capacity, the battery module 4 is charged at this time, and the energy consumption of the equipment load is not enough to consume all the power generation capacity, and power abandonment often occurs. This part of the electricity can be used to heat the battery body using the battery electric heating module; Use the following steps to keep warm and dissipate heat: S21 determines the working mode of the insulation cover 3 of the battery module 4 according to the operation status of the battery electric heating module in the last 24 hours: if the battery electric heating module has been started, the opening and closing mechanism is controlled to close the insulation cover, and the insulation cover 3 operates in the insulation mode; if the battery electric heating module has not been started, the opening and closing mechanism is controlled to open the insulation cover, and the insulation cover 3 operates in the heat dissipation mode.

[0016] Based on the same inventive concept, the present application also discloses a dual energy storage system for solar power storage and heat storage, including a photovoltaic component 1, a voltage conversion module 2, a heating control device, an environmental collection device, a thermal insulation cover 3, a battery module 4, a thermal insulation cover and an opening and closing mechanism arranged oppositely, the battery module 4, the voltage conversion module 2, etc. can be directly or indirectly installed vertically on the pole, the photovoltaic component 1 charges the battery module 4 through the voltage conversion module 2, the voltage conversion module 2 can be a photovoltaic controller, the battery module 4 includes a battery management system and a battery electric heating module, the battery management system obtains the battery charging and discharging state, battery power and line voltage output by the photovoltaic component 1, the battery electric heating module uses a heating plate or heating film composed of a heating resistor wire, or a heating module achieved by electric heating methods such as a PTC heater and a semiconductor heater, and the battery electric heating module is arranged on the surface of the overall battery cell group. The side with the largest area heats the battery cell group when needed; the insulation sleeve 3 is sleeved on the outside of the battery module 4, and there is a spaced cavity between the insulation sleeve 3 and the outer shell of the battery module 4 to form a convection channel, the insulation sleeve covers are respectively arranged on the opposite openings of the insulation sleeve 3 and are controlled by the opening and closing mechanism to use the aforementioned solar energy dual energy storage method to close or open the insulation sleeve cover and the insulation sleeve 3, and the heating control device uses the aforementioned solar energy storage and heat storage dual energy storage method to turn on the battery electric heating module. The heating control device can be an independent device, including an external memory, an operating internal memory and a processor for computer programs, and can also be integrated into the voltage conversion module 2 or the battery management system of the battery module 4, so that the intelligent control function of the solar energy storage and heat storage dual energy storage method can be realized in the lithium battery itself, without the need for external equipment and sensor support, each battery pack is self-contained, and no communication and assistance are required, thereby achieving minimal control.

[0017] In this embodiment, the insulation sleeve 3 includes an outer shell and an inner insulation layer, one opposite side of the top of the outer shell is higher than the insulation layer, and the four sides of the bottom of the outer shell are lower than the insulation layer. The insulation sleeve cover includes a hood 5 outside the top of the insulation sleeve 3 and a baffle 6 inside the bottom of the insulation sleeve, the hood 5 has a brim covering the outside of the insulation sleeve 3, the baffle 6 is located in the outer shell but outside the insulation layer, the baffle 6, the hood 5 and the baffle 6 are directly sealed and connected to the insulation sleeve 3 on one set of opposite sides, and the other set of opposite sides leaves an opening for the door panel 74 to close or open. For the reliability and intelligent controllability of opening and closing, the opening and closing mechanism of this embodiment uses an electrically automatic control opening and closing mechanism, and the electrically automatic control opening and closing mechanism includes a motor 71, a pull rod 72 , pull rod 73, door panel 74, door panel shaft fixing block 75, the motor 71 is fixedly mounted at the inner center of the hood 5 and the baffle 6, the pull strip center is fixed on the motor 71 shaft and rotates around the motor in a plane parallel to the hood 5 and the baffle 6, the door panel 74 is fixed in the door panel shaft fixing block 75 through the door panel shaft 741 at its edge, the door panel 74 rotates around the door panel shaft 741, the door panel shaft fixing block 75 is fixed at a position corresponding to the edge of the insulation cover and the inner wall of the insulation cover 3, one end of the pull rod 73 is fixed at the far end of the pull strip 72, and the other end is fixed at the far end of the door panel shaft 741 of the door panel 74, when the motor 71 rotates, it drives the door panel 74 to close or open the insulation cover and the insulation cover 3. In this embodiment, the motor 71 drives the pull strip 72 and the pull rod 73 so that the door panel 74 can be in the sealing position, that is, the insulation cover and the insulation cover 3 are closed, the ventilation position, that is, the insulation cover and the insulation cover 3 are open, and the intermediate process position, as shown in the accompanying drawings.

[0018] In addition to the electric automatic control opening and closing mechanism, the opening and closing mechanism can also use a natural control method that does not require control, such as a thermal bimetallic bracket. This method is low-cost and does not consume electricity, but is unreliable and cannot be controlled manually. In addition to the control method of the motor pull rod damper disclosed in this embodiment, the electric automatic control opening and closing mechanism can also use other control schemes such as a bistable electromagnet and an electric push rod.

[0019] When the battery electric heating module has been started in the last 24 hours, the hood 5 and the baffle 6 are closed to form a closed cavity, and the insulation layer of the insulation sleeve can be used to effectively keep the battery module 4 warm. The inner side of the insulation layer of this embodiment is filled with phase change material, which can not only store more thermal energy, but also release heat to the inside during the cooling phase change to achieve a heating effect. Although the phase change material can store more thermal energy, the thermal conductivity of the phase change material itself is relatively large, and the insulation layer can be implemented with multi-layer materials, such as phase change material on the inside and conventional materials such as polystyrene foam or insulation cotton on the outside. In this embodiment, in the scenario where the ambient temperature drops at night, night falls and the ambient temperature drops. The battery module 4 uses its own stored heat and the good insulation performance of the insulation sleeve 3 to ensure that the battery module 4 can be kept above 0°C throughout the night, thereby ensuring the normal discharge of the battery and the cycle life of the battery.

[0020] When the battery electric heating module has not been started in the last 24 hours, the hood 5 and the baffle 6 are opened, the cavity is connected up and down, forming a chimney effect, and the heat of the battery module 4 body can be taken away by the flowing air. At the same time, the existence of the insulation cover 3 shell also blocks the radiation of the sun, which is equivalent to a sunshade, further preventing the battery module 4 from overheating. When the upper and lower openings of the insulation cover are not in a vertical direction, a fan can also be added inside the insulation cover to help dissipate heat.

[0021] In the description of the present application, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, if the terms "first", "second", etc. appear, they are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0022] The above is only a preferred specific implementation method of the present scheme, but the protection scope required by the present scheme is not limited thereto. Any technician familiar with the technical field can make equivalent substitutions or changes according to the technical scheme and inventive concept of the present application within the technical scope disclosed in the present application, which should be covered by the protection scope of the present application.

Claims

1. A dual energy storage method for solar energy electricity storage and heat storage, characterized in that: Use the following steps to turn on power storage: When the line voltage output by the photovoltaic module (1) is greater than the charging start voltage of the battery module (4), the charging function of the battery module is turned on; Use the following steps to turn on thermal storage: S11 records the temperature change curve of the built-in temperature sensor of the battery module (4) in the last 24 hours, and takes the minimum value t1; S12 calculates the heating temperature target setting value t0 of the battery electric heating module according to the calculation frequency, t0=T-t1, where T is a heating temperature constant, the heating temperature constant has a value range of 35°C±3°C, and the calculation frequency has a value range of 0.6 times / hour to 12 times / hour; S13 compares the current temperature of the battery module (4) with the heating temperature target setting value t0, and when t0 is greater than the current temperature of the battery module (4) and the line voltage output by the photovoltaic module (1) is greater than the charging rated voltage of the battery module (4), turns on the battery electric heating module; The following steps are used to switch the heat preservation and heat dissipation modes of the heat preservation cover (3) of the battery module (4): S21 determines the working mode of the thermal insulation cover (3) of the battery module (4) based on the operation status of the battery electric heating module in the last 24 hours: if the battery electric heating module has been started, the opening and closing mechanism is controlled to close the thermal insulation cover, and the thermal insulation cover (3) operates in the thermal insulation mode; if the battery electric heating module has not been started, the opening and closing mechanism is controlled to open the thermal insulation cover, and the thermal insulation cover (3) operates in the heat dissipation mode.

2. The dual energy storage method of solar energy electricity storage and heat storage according to claim 1 is characterized in that: The heating temperature constant is 35°C.

3. The dual energy storage method of solar energy electricity storage and heat storage according to claim 1 is characterized in that: The calculation frequency used is once per hour.

4. A solar energy dual energy storage system for storing electricity and heat, comprising a photovoltaic module (1), a voltage conversion module (2), and a battery module (4), wherein the photovoltaic module (1) supplies power to an electrical device and charges the battery module (4) via the voltage conversion module (2), wherein the battery module (4) comprises an inner shell, a battery cell group, a battery management system, and a battery electric heating module, wherein the battery management system obtains the charge and discharge state of the battery, the battery power, and the line voltage output by the photovoltaic module (1), and is characterized in that: It also includes a heating control device, an ambient temperature collection device, a thermal insulation sleeve (3), a thermal insulation sleeve cover arranged oppositely, and an opening and closing mechanism, wherein the thermal insulation sleeve (3) is sleeved on the outside of the battery module (4) to form a spacing cavity therebetween, the thermal insulation sleeve covers are respectively arranged at the opposite openings of the thermal insulation sleeve (3) and are controlled by the opening and closing mechanism, the opening and closing mechanism uses the dual energy storage method of solar energy storage and heat storage as described in any one of claims 1 to 3 to close or open the thermal insulation sleeve cover and the thermal insulation sleeve (3), and the heating control device uses the dual energy storage method of solar energy storage and heat storage as described in any one of claims 1 to 3 to open the battery electric heating module.

5. The solar energy storage and heat storage dual energy storage system according to claim 4 is characterized in that: The opening and closing mechanism uses an electric automatic control opening and closing mechanism.

6. The solar energy storage and heat storage dual energy storage system according to claim 5 is characterized in that: The electric automatic control opening and closing mechanism comprises a motor (71), a pull rod (72), a pull rod (73), a door panel (74), and a door panel axis fixing block (75); the motor (71) is fixedly mounted at the inner center of the thermal insulation cover; the pull rod center is fixed on the shaft of the motor (71) and rotates around the motor in a plane parallel to the thermal insulation cover; the door panel (74) is fixed in the door panel axis fixing block (75) via the door panel axis (741) at its edge; the door panel (74) rotates around the door panel axis (741); the door panel axis fixing block (75) is fixed at a position corresponding to the edge of the thermal insulation cover and the inner wall of the thermal insulation cover (3); one end of the pull rod (73) is fixed to the distal end of the pull rod (72), and the other end is fixed to the distal end of the door panel axis (741) of the door panel (74); when the motor (71) rotates, it drives the door panel (74) to close or open the thermal insulation cover and the thermal insulation cover (3).

7. The solar energy storage and heat storage dual energy storage system according to claim 4 is characterized in that: The thermal insulation sleeve (3) comprises an inner thermal insulation layer, the interior of the thermal insulation layer being filled with a phase change material.

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