Electric energy management system with thermoelectric power supply conversion function

An electric energy management system with thermoelectric power supply conversion function includes a controller, multiple first battery modules, a second battery module and a connection switching module. Each first battery module includes a first battery and a thermoelectric unit. The multiple first battery modules and the second battery module supply power to high-voltage equipment and low-voltage equipment, respectively. Connection ends of the multiple thermoelectric units are connected to the connection switching module. When the first batteries are discharging, the controller controls the connection switching module to make the thermoelectric units connected in series between the two series connection ends for supplying electric energy to the second connection end of the second battery module. The thermoelectric unit converts the thermal energy generated by the first battery and provides it to the low-voltage device, thereby reducing the electrical energy that the second battery module outputs and improving energy utilization efficiency.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electric energy management system, in particular to an electric energy management system with thermoelectric power supply conversion function.

2. Description of the Prior Arts

Environmental protection and energy saving are one of the main trends of scientific and technological development in recent years. Therefore, rechargeable batteries that can be repeatedly charged and discharged are widely used in various daily appliances and industries, ranging from rechargeable batteries that meet the specifications of dry batteries, rechargeable razors and vacuum cleaners to electric motorcycles and electric vehicles. In order to meet the usage habits of general consumers and improve the convenience of such charging products, the charging efficiency and safety of rechargeable batteries are the key characteristics that must be considered and improved at the same time. The rechargeable battery made of any material has a battery temperature range for proper operation. When the battery temperature is higher or lower than the temperature range, it is not conducive to the charge and discharge of the rechargeable battery.

However, battery charging and discharging are accompanied with release of heat energy. When the charging/discharging speed is faster, the charging/discharging current is greater, and the rechargeable batteries generate a lot of heat that raises the battery temperature. If the heat generated is not dissipated in time, the temperature of the rechargeable battery rises to overheating during charging and discharging, resulting in the risk of battery destruction or even bursting and explosion. The waste heat generated by these rechargeable batteries not only raises the risk of damage to the batteries, but also raises the ambient temperature. In the prior art, active cooling and heat dissipation of the battery is commonly done, such as fans, thermoelectric elements, etc. However, additional electricity is required for heat exhaust, which is not conducive to energy efficiency.

In summary, the existing battery temperature management technology needs to be further improved.

SUMMARY OF THE INVENTION

In view of the above problems that the waste heat generated by charging and discharging of rechargeable batteries cannot be handled efficiently, the present invention provides an electrical energy management system with a thermoelectric power supply conversion function, comprising:a controller;multiple first battery modules, including:a first battery having two first connection ends that are connected to a high-voltage device to supply power to the high-voltage device;a thermoelectric unit having a first surface and a second surface opposite to each other, and having two connection ends; wherein the first battery is arranged on the first surface of the thermoelectric unit such that a surface of the first battery contacts the first surface of the thermoelectric unit;a second battery module having two second connection ends that are connected to a low-voltage device to supply power to the low-voltage device;a connection switching module electrically connected to the two connection ends of each thermoelectric unit and the controller, and having two series connection ends that are connected to the two second connection ends of the second battery module;wherein, when the first batteries of the multiple first battery modules are in a discharging state, the controller controls the connection switching module to connect the thermoelectric units in series between the two series connection ends, so that the multiple thermoelectric units connected in series output electric energy to the second connection end.

The thermoelectric units of the present invention are thermoelectric coolers. Preferably, each thermoelectric unit is a semiconductor thermoelectric cooler chip. The thermoelectric cooler is made of two different thermoelectric materials. According to the principle of thermoelectric effect, when the first side and the second side have the heat generated by the environment, a potential difference is generated between the two connection ends of the thermoelectric unit. In contrast, when a voltage is provided to the second connection of the thermoelectric unit, a temperature difference is actively generated between the first and second surfaces of the thermoelectric unit to achieve the effect of cooling or heating.

In the power management system with thermoelectric power conversion function of the present invention, each first battery is arranged on a first side of a thermoelectric unit. The connection ends of each thermoelectric unit are connected to the connection ends of a connection switching module. The connection switching module can switch the connection status according to the control signal of the controller. In the discharging state, the first batteries of the multiple first battery modules generate heat and the temperature of the first side of each thermoelectric unit is higher than that of the second side facing the external environment, which results in a potential difference between the two connected ends of each thermoelectric unit. The controller controls the connection switching module to connect each thermoelectric connection in series, so that the potential difference generated by each thermoelectric unit is output in series from the two series connections to the second connection of the second battery module, and is output to the low-voltage device in parallel with the second battery module.

The thermoelectric units in the multiple first battery modules of the present invention convert the heat energy generated by the first battery into electrical energy, and the total output voltage can be improved by connecting the connection switching module in series. The total output voltage is provided to the second battery module as a parallel output, thereby reducing the load electrical energy to be output by the second battery module. With the thermoelectric conversion effect of the thermoelectric unit, the waste heat generated by the first batteries is effectively recovered and reused while keeping the first batteries normal, thereby improving the overall energy use efficiency of the power management system.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring toFIG.1, the power management system with thermoelectric power supply conversion function of the present invention mainly includes a controller10, multiple first battery modules20, a second battery module30and a connection switching module40. The multiple first battery modules20respectively include a first battery21and a thermoelectric unit22. Two first connection ends N1and N2of the first battery21are connected to a high-voltage device51to supply power to the high-voltage device51. The thermoelectric unit22has a first surface221and a second surface222opposite to each other, and has two connection ends P1and P2. The first battery21is disposed on the first surface221of the thermoelectric unit22to make a surface of the first battery21contact the first surface221of the thermoelectric unit22. The second battery module30has two second connection ends N3and N4, and the two second connection ends N3and N4are connected to a low-voltage device52to supply power to the low-voltage device52.

The power management system with thermoelectric power supply conversion function of the present invention can be applied to a power supply system of an electric vehicle. The high-voltage device51requires a higher input voltage than the low-voltage device52. The high-voltage device51can be, for example, a power motor of an electric vehicle, which requires an input voltage of 300 V to 400V. The low-voltage equipment52can be, for example, an electronic equipment other than the power motor on the electric vehicle, such as a lighting system, an instrument panel system, or audio equipment, etc., which requires an input voltage of 12V or 48V. Therefore, the first batteries21of the multiple first battery modules20are power batteries for supplying power to the multiple high-voltage devices51. The multiple first batteries21can be, for example, connected in series to supply power to the high-voltage device51. The second battery module30is another battery module in addition to the power batteries, such as a 12V battery, or a 48V output formed by multiple 12V batteries connected in series, but not limited to this.

The connection switching module40is electrically connected to the two connection ends P1, P2of each thermoelectric unit22and the controller10, and has two series connection ends S1, S2. The two series connection ends S1, S2are connected to the two second connecting ends N3and N4of the second battery module30. When the first batteries21of the multiple first battery modules20are in a discharging state, the controller10controls the connection switching module40to connect each of the connections ends P1, P2in series between the two series connections S1, S2. So the multiple thermoelectric units22are connected in series through the connection switching module40and output electrical energy to the second connection ends N3, N4.

The discharging state of the multiple first battery modules20is a state in which the multiple first batteries21supply power to the high-voltage device51through the first connection ends N1and N2. When the first battery generates heat by discharging and causes the surface temperature to rise, the temperature of the first surface221of the thermoelectric unit22is higher than the temperature of the second surface222, so a potential difference is generated between the two connection ends P1and P2of the thermoelectric unit22. At this time, the controller10controls the connection switching module40to connect the two connection ends P1and P2of the thermoelectric units22in series between the two series connection ends S1and S2. In other words, the thermoelectric units22are connected in series, and the potential difference between the two series connection ends S1and S2is the sum of the potential differences of the thermoelectric units22.

Referring toFIG.2, in one embodiment, each of the first battery modules20further includes a temperature sensor23that is disposed on a temperature measuring surface of the first battery21and is electrically connected to the controller10. The temperature sensor23generates a temperature sensing information according to a surface temperature of the temperature measuring surface of the first battery21and sends the temperature sensing information to the controller10. When the first batteries21of the multiple first battery modules20are in the discharged state, the controller10first determines whether the surface temperatures of the multiple first batteries21is greater than a first threshold based on the temperature sensing information of the multiple temperature sensors23. If the surface temperature of the multiples first batteries21is greater than the first threshold, the controller10controls the connection switching module40to connect the connection ends P1and P2of the thermoelectric units22in series between the two series connection ends S1and S2.

Since the potential difference generated by the thermoelectric unit22is positively correlated with the temperature difference between the first surface221and the second surface222, even if each of the thermoelectric units22is in the discharging state, the total potential difference generated by the multiple thermoelectric units22may be too low to be effectively utilized when the surface temperature of each of the first batteries21does not rise. Therefore, after confirming that the first battery modules20are in the discharging state, the controller10further determines that the surface temperature of the multiple first batteries21is greater than a first threshold before connecting the connection ends P1and P2of the multiple thermoelectric units22in series to output electrical energy to the second connection ends N3and N4via the connection switching module40. In a preferred embodiment, the controller10calculates the average value of the surface temperature of each of the first batteries21based on the temperature sensing information of each of the temperature sensors23. When the average value is greater than the first threshold, the controller10confirms that the surface temperature of the multiple first batteries21is greater than the first threshold.

Referring toFIG.1, in an embodiment of the present invention, the power management system with thermoelectric power supply conversion function further comprises a power supply module60electrically connected to the connection switching module40and the first battery21of each of the first battery modules20. The power supply module60is electrically connected to an external power source to receive an external voltage, then convert the external voltage to a charging voltage and a supply voltage. When the multiple first batteries21are in the charging state, the power module60provides the charging voltage to each of the first batteries21and provides the supply voltage to the connection switching module40. The connection switching module40receives the supply voltage, and the controller10controls the connection switching module40to provide the supply voltage to each of the thermoelectric units22through the connection ends P1, P2

When the power supply module60provides a charging voltage to each of the first batteries21for charging, the power supply module60also provides a supply voltage to each of the thermoelectric units22through the connection switching module40. According to the operating principle of the thermoelectric unit22, when the two connection ends P1and P2of the thermoelectric unit22receive a voltage, the first surface221and the second surface222of the thermoelectric unit22actively generate a temperature difference. The temperature of the first surface221is higher or lower than the temperature of the second surface222depending on the positive or negative polarity of the voltage. For example, when the supply voltage is a first voltage, the temperature of the first surface221of the thermoelectric unit22is lower than the temperature of the second surface222. When the supply voltage is a second voltage with the opposite polarity to the first voltage, the temperature of the first surface221of the thermoelectric unit22is higher than the temperature of the second surface222. As the first battery21is arranged on the first surface221of the thermoelectric unit22, when the temperature of the first surface221is lower than the temperature of the second surface222, the thermoelectric unit22can cool down the first battery21. Conversely, the thermoelectric unit22can heat the first battery21. Thus, by controlling the power supply module60to provide supply voltage, the controller10can maintain a stable temperature of each first battery21while the power supply module60charges each first battery21according to the temperature information provided by the temperature sensor23.

In an embodiment, when the first battery21of each of the first battery modules20is in a discharging state, the controller10determines whether the surface temperature of each of the first batteries21is greater than a second threshold based on the temperature sensing information of the multiple temperature sensors23. If the surface temperature of one of the first batteries21is greater than the second threshold, the controller10determines that the first battery module20where the first battery21is located is in an over-temperature state. Then, the controller10controls the power supply module60to receive a battery voltage from the other first battery21, provide the battery voltage to the connection switching module40, and then control the connection switching module40to provide the battery voltage to the thermoelectric unit22of the first battery module20in the overtemperature state through the connection ends P1and P2.

In this embodiment, the second threshold is greater than the first threshold. Each of the first batteries21has an upper normal temperature limit. When the surface temperature of any of the first batteries21is higher than the second threshold, it means that the first batteries21are in an abnormal over-temperature state. Therefore, the controller10receives the battery voltage of the other (non-over-temperature) first battery21by the power supply module60, and provides the battery voltage to the thermoelectric unit of the over-temperature first battery module20through the connection switching module40, so that the thermoelectric unit22of the over-temperature first battery module20cools down the first battery21in the over-temperature state, and the temperature of the first battery21in the over-temperature state does not continue to rise abnormally, thereby ensuring the safety of the battery.

Referring toFIG.3, preferably, the connection switching module40comprises multiple switches41. The number of the switches41is equal to the number of the first battery modules20, that is, equal to the number of the thermoelectric units22, so as to control the connection modes of the connection ends P1and P2of the thermoelectric units22respectively. Each switch41has a control end ct1, two inputs IP1, IP2, two parallel ends a1, a2and two series ends b1, b2respectively. The control end ct1is connected to the controller10to receive control signals from the controller10. In one embodiment, the control end ct1of each switch41is connected to the controller10in a serial connection to transmit the control signals from the controller10. The two inputs IP1and IP2are connected to the two connection ends P1and P2of one of the thermoelectric units22. The two parallel ends a1and a2are connected to the power module60to receive the supply voltage or battery voltage from the power module60. The series ends b1and b2of the multiple switches41are connected in series between the two series connection ends S1and S2of the connection switching module40. Each switch41controls the two inputs IP1and IP2to be electrically connected to the two parallel ends a1and a2or the two series ends b1and b2based on the control signal of the controller10. In an embodiment, the switch41can also prevent the two input ends IP1and IP2from connecting the parallel ends a1, a2or the series ends b1, b2, and the thermoelectric unit22connected to the input terminals IP1, IP2of the switch41cannot receive or input a voltage.

When each first battery21is in the discharging state and the controller10controls the connection switching module40to connect the connection ends P1and P2of each thermoelectric unit22in series between the two series connection ends S1and S2, the controller10generates a control signal that controls each of the switches41to connect the inputs IP1and IP2to the series ends b1and b2. Then the two connection ends P1, P2of each thermoelectric unit22are connected in series between the two series connection ends S1and S2of the switching module40. That is, each of the thermoelectric units22is connected in series between the two series connection ends S1and S2to output electric energy to the two connection ends P1and P2.

Further, when each of the first batteries21is in the discharging state and the controller10determines that one of the first battery modules20is in the over-temperature state, the controller10sends a designated cooling control signal to the control end ct1of each switch41of the connection switching module40, which can make the switch41connected to the thermoelectric unit22of the first battery module20in the over-temperature state connect the inputs IP1and IP2to the parallel ends a1and a2. At this time, the power module60provides the battery voltage of the first battery21in the non-over-temperature state to the two parallel ends a1, a2, so that the thermoelectric unit22of the first battery module20in the over-temperature state receives the battery voltage to cool down the first battery21in the over-temperature state.

When each of the first batteries21is in the charging state, the controller10controls each of the switches41to connect the inputs IP1and IP2to the parallel ends a1and a2. At this time, the power supply module60provides the supply voltage to the parallel ends of the switches41, so that each thermoelectric unit22receives the supply voltage to cool down or heat each first battery21. In an embodiment, when in the charging state, the controller10can determine that the surface temperature of each of the first batteries21is higher or lower than an optimal temperature based on the multiple temperature sensing information. If the surface temperature of each of the first batteries21is higher than the optimal temperature, it means that each of the first batteries21needs to be cooled down, and then the power module60is control led to provide the first voltage. If the surface temperature of each of the first batteries21is lower than the optimal temperature, it means that each of the first batteries21needs to be heated up, and then the power module60is controlled to provide the second voltage.

Referring toFIG.4andFIG.5, in an embodiment of the present invention, the multiple first batteries21are cylindrical batteries, and each first battery21has a side surface211and two end portions212. The two end portions212are respectively disposed on opposite ends of the side surface211, and the two first connecting ends N1and N2are formed on the two end portions212of the battery. Wherein, the first surface221of each thermoelectric unit22is attached to the side surface211of each cylindrical battery. Preferably, the multiple thermoelectric units22are flexible thin-film semiconductor thermoelectric cooling chips, that is, the multiple thermoelectric units22are flexible and bendable. Therefore, no matter whether the first battery21is a cylinder, a square column or a plate, the thermoelectric unit22can change its shape according to the surface of the first battery21, so as to closely attach to the surface of the first battery21, thereby achieving a better heat transfer efficiency.

Further, as shown inFIG.6, the power management system with thermoelectric power conversion function further comprises a housing70. The housing70has a housing space700, a first fan opening701, and a second fan opening702. The multiple first battery modules20and the power supply module60are provided in the housing space700of the housing70. The first fan opening701is formed in one side of the housing70, and the second fan opening702is formed in the other side of the housing70opposite to the first fan opening701. Both the first fan opening701and the second fan opening702are connected to the housing space700. The first fan device81exhausts air in the same direction of the second fan device82. For example, the first fan device81exhausts air from the housing space700to the outside of the housing70, and the second fan device82exhausts air from the outside into the housing space700. Compared with the single-side fan device, the present invention further provides fan devices on both sides of the housing70. When the thermoelectric unit22cools down the first battery21and the heat energy accumulates in the housing space700of the housing70, the first fan device81and the second fan device82on both sides make the air flow quickly and discharge the waste heat out of the housing70. In a preferred embodiment, the first fan device81and the second fan device82are digital frequency variable fans that have high speed and avoid excessive power consumption in heat extraction, thereby improving energy efficiency.

In summary, in the electric energy management system with thermoelectric power conversion function of the present invention, the thermoelectric units11disposed on the surface of the first batteries21can effectively manage the thermal energy generated by the first batteries21, actively cool down the first batteries21or convert waste heat into electric energy within an appropriate range. When the system is connected to an external power source for charging, the power module can further cool down or heat the multiple first batteries21through the external power source. When the first batteries21are discharging, such as when an electric vehicle is running, the first battery module20can supply power to the power motor, the second battery module30can supply power to other first voltage devices, and the thermoelectric units22can convert the waste heat generated by the first batteries21, and then are connected to the second battery module30to supply power to the low-voltage equipment. Then the waste heat is recovered for power supply to reduce the electric energy that the second battery module30needs to output. When one of the first batteries21is in an abnormal over-temperature state, the power of the other first batteries21can be used to cool down the over-temperature first battery21through the power module to ensure the safety of the electrical energy system.