JP7300267B2 - Thermal power generation module - Google Patents

Description

TECHNICAL FIELD The present invention relates to a thermal power generation module that supplies electric power by thermal power generation.

Recently, a heat-utilizing power generation element that does not require a temperature gradient has been developed (see Patent Document 1 below). This heat-utilizing power generation element can perform heat-utilizing power generation by directly converting thermal energy into electrical energy without giving a temperature gradient. For this reason, heat-utilizing power generation elements are expected to be used in power generation systems that utilize geothermal heat, exhaust heat from automobiles, exhaust heat from factories, and the like. On the other hand, conventionally, a power supply system using a secondary battery has also been used (see Patent Document 2 below).

International Publication No. 2017/038988 JP-A-2003-111289

In a power generation system using the heat-utilizing power generation element described above, there is a tendency to require a continuous power supply. On the other hand, the duration of the power generation capacity of a single heat-utilizing power generation element tends to become shorter as the amount of power supplied increases. Moreover, when the power generation capacity of the heat-utilizing power generation element was lowered, a phenomenon was observed in which the power generation capacity recovered when the load was reduced. Therefore, in a power generation system using heat-utilizing power generation elements, appropriate control is required to achieve continuous power supply. In addition, in the power supply system described in Patent Document 2, control is performed to replace a degraded secondary battery with another secondary battery by operating a switch, but there is a limit to continuous power supply. There is

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a heat-utilizing power generation module capable of achieving continuous power supply.

In order to solve the above problems, a heat-utilizing power generation module according to one aspect of the present invention includes a plurality of heat-utilizing power generation cells including heat-utilizing power generation elements capable of heat-utilizing power generation, which are electrically connected in parallel to a load. and a plurality of heat utilization power generation batteries provided on a connection path between the load and each of the heat utilization power generation batteries for turning on/off the electrical connection between each of the plurality of heat utilization power generation batteries and the load switch, a voltage detection unit that detects the potential difference between the two electrodes of a plurality of heat-utilizing power generation batteries, and based on the result of comparison between the potential difference detected by the voltage detection unit and a specified value, one of the plurality of switches is turned on. a control unit for controlling the plurality of switches such that at least one switch in the state transitions to the off state and at least one switch in the off state transitions to the on state.

According to the heat utilization power generation module according to the above aspect, when power is supplied to a load using a plurality of heat utilization power generation batteries including heat utilization power generation elements electrically connected in parallel to the load, , based on the result of comparison between the potential difference between both electrodes of a plurality of heat-utilizing power-generating batteries and the specified value, heat-utilizing power-generating batteries that are disconnected from the load and heat-utilizing power-generating batteries that are connected to the load. can be replaced with As a result, power can be alternately supplied to the load from the heat-utilization power generation batteries according to the potential difference between the two electrodes of the heat-utilization power generation batteries, and the power supply can be continued according to the size of the supplied power. power supply can be realized.

Here, in the heat-utilization power generation module according to the above aspect, the voltage detection unit is configured to be capable of detecting a potential difference applied to the load from the plurality of heat-utilization power generation batteries, and the control unit detects the potential difference by the voltage detection unit. It is preferable to control the plurality of switches such that the switches in the off state among the plurality of switches are sequentially switched at the timing when it is determined that the applied potential difference has fallen below the specified value. By adopting such a configuration, one of the plurality of heat-utilizing power-generating batteries is cut off from the electrical connection with the load when the potential difference applied to the load from both electrodes of the plurality of heat-utilizing power-generating batteries decreases. They can be replaced sequentially. As a result, while reducing the number of heat-utilization power generation batteries, continuous power supply can be efficiently realized according to the magnitude of power supplied from each heat-utilization power generation battery.

In addition, the voltage detection unit is configured to be capable of independently detecting a potential difference between both electrodes of each of the plurality of heat-utilizing power generation batteries, and the control unit determines that the potential difference detected by the voltage detection unit is below a specified value. A switch corresponding to a battery that is in an ON state, the switch corresponding to a heat-utilizing power generation battery for which it is determined that the potential difference detected by the voltage detection unit exceeds a specified value by transitioning the switch from the ON state to the OFF state. , to transition the switch in the OFF state to the ON state. In this case, it is possible to switch the electrical connection between the plurality of heat utilization power generation batteries and the load at appropriate timing according to the power generation capacity of each of the plurality of heat utilization power generation batteries, thereby reducing the number of heat utilization power generation batteries. Continuous power supply can be efficiently realized according to the amount of power supplied from each heat utilization power generation battery.

Furthermore, it is also preferable that the control unit controls the plurality of switches such that the switch in the OFF state among the plurality of switches is sequentially switched over time. This makes it possible to reduce the number of heat-utilizing power generating batteries and realize continuous power supply more efficiently according to the magnitude of the power supplied from each heat-utilizing power generating battery.

Further, the controller further includes a current detector for detecting current supplied from the plurality of heat-utilizing power generation batteries to the load, and the controller detects the potential difference detected by the voltage detector and the current detected by the current detector. It is also preferable to control the plurality of switches to change the number of thermal power generation batteries electrically connected to the load at the same time based on the power corresponding to . By adopting such a configuration, by changing the number of heat-utilizing power generation batteries electrically connected to the load at the same time according to the amount of power to be supplied, it is possible to reliably realize continuous power supply.

According to the present invention, it is possible to provide a heat-utilizing power generation module capable of realizing continuous power supply.

1 is a circuit diagram showing the configuration of a heat-utilizing power generation module 1 according to an embodiment; FIG. FIG. 2 is a diagram showing the configuration of heat-utilizing power generation elements incorporated in heat-utilizing power generating batteries 3a, 3b, and 3c of FIG. 1; 2 is a flow chart for explaining a control function of switches 5a, 5b, and 5c by a controller 11 of FIG. 1; FIG. 4 is a timing chart showing on/off states of switches 5a, 5b, and 5c that transition over time under the control shown in FIG. 3; FIG. FIG. 2 is a flowchart for explaining a change control function of the number of batteries by the controller 11 of FIG. 1; FIG. FIG. 6 is a timing chart showing on/off states of switches 5a, 5b, and 5c that transition over time under the control shown in FIG. 5; FIG. FIG. 10 is a circuit diagram showing the configuration of a heat-utilizing power generation module 1A according to a modification; FIG. 8 is a flow chart for explaining control functions of switches 5a, 5b, and 5c by a controller 11A of FIG. 7; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted.

FIG. 1 is a circuit diagram showing the configuration of a heat-utilizing power generation module 1 according to an embodiment. The heat utilization power generation module 1 is used by being incorporated in devices such as sensors for transportation devices such as automobiles, power generation devices using geothermal heat, etc., and devices such as various sensors in factories, offices, etc., and uses thermal energy. It is a power supply system that supplies electric power. The heat utilization power generation module 1 can also be said to be a device that utilizes heat to generate current. As shown in FIG. 1, the heat utilization power generation module 1 is composed of a plurality of heat utilization power generation batteries (hereinafter abbreviated as "batteries") 3a, 3b and 3c each containing a heat utilization power generation element capable of heat utilization power generation. a battery group 3, a plurality of switches 5a, 5b, and 5c provided corresponding to the plurality of batteries 3a, 3b, and 3c, and voltage sensors (voltage detection units) provided corresponding to the plurality of batteries 3a, 3b, and 3c 7 a , 7 b , 7 c , a current sensor (current detection section) 9 , and a controller (control section) 11 . A load L such as a sensor is electrically connected to the heat utilization power generation module 1 . In FIG. 1 , solid lines indicate electrical connection paths between components, and dotted lines indicate paths of signals exchanged between the controller 11 and each component.

Note that the number of batteries constituting the battery group 3 is not limited to a specific number. In this embodiment, a case where the number of batteries is three will be described as an example.

Each of the plurality of batteries 3a, 3b, and 3c is a battery containing a heat-utilizing power generation element, and as its configuration, the configuration described in International Publication No. 2017/038988 can be adopted. FIG. 2 shows a configuration example of the heat-utilizing power generation element 13 incorporated in the batteries 3a, 3b, and 3c. In this way, the heat-utilizing power generation element 13 has three layers, the electron transport layer 17, the charge heat excitation material layer 19, and the ion redox layer 21, which are laminated between the two electrode layers of the negative electrode 15a and the positive electrode 15b. It is configured.

Charge-thermally excited material layer 19 includes a semiconductor material that absorbs heat to generate thermally excited electrons and holes. The ionic redox layer 21 comprises a solid electrolyte or electrolyte solution in which charge-transporting ion pairs can migrate. The term "charge-transporting ion pair" as used herein refers to two stable ions with different valences, one of which is oxidized or reduced to become the other ion, which can carry electrons and holes. is. The electron transport layer 17 is a layer that contains an electron transport material such as a semiconductor or a metal and transports thermally excited electrons generated in the charge thermally excited material layer 19 . However, in the heat-utilizing power generation element 13, the electron transport layer 17 may be omitted.

In the heat-utilizing power generation element 13 having the above configuration, thermally excited electrons e ⁻ and holes h ⁺ are generated when heat is absorbed in the charge-thermally excited material layer 19 , and the thermally excited electrons e ⁻ are directed toward the electron transport layer 17 . Moving. Holes h ⁺ generated in the charge-thermal excitation material layer 19 oxidize ions X, which are one of the charge-transporting ion pairs, at the interface between the charge-thermal excitation material layer 19 and the ion redox layer 21 to change into the other ions Y. (X+h ⁺ →Y). The excess electrons e ⁻ in the electron transport layer 17 move to the outside through the negative electrode 15a, and then move through the load L to the positive electrode 15b. At this time, work is performed in the load L by power generation in the heat utilization power generation element 13 . Furthermore, the electron e ⁻ that has moved to the positive electrode 15b reduces the ion Y at the interface between the positive electrode 15b and the ion oxidation-reduction layer 21 to change it into the ion X (Y+e ⁻ →X). Ions Y generated at the interface between the ionic redox layer 21 and the charge heat excitation material layer 19 and ions X generated at the interface between the ionic redox layer 21 and the positive electrode 15b diffuse in the ionic redox layer 21. This relaxes ion localization within the layer. By repeating the movement of the thermally excited electrons e ⁻ and the diffusion of the charge-transporting ion pair, power generation by the thermal power generation element continues.

Each of the plurality of batteries 3a, 3b, and 3c is a battery containing one or a plurality of heat-utilizing power generation elements 13 therein. When the batteries 3a, 3b, and 3c are provided with a plurality of heat-utilizing power generating elements 13, the batteries 3a, 3b, and 3c include the plurality of heat-utilizing power generating elements 13 internally connected to each other in series.

In each of the batteries 3a, 3b, and 3c having such a configuration, as described above, electric power is supplied by movement of thermally excited electrons e ⁻ , and charges are generated in the ion redox layer 21 in the thermal power generation element 13. Power supply is maintained by repeating diffusion of transport ion pairs in parallel. At this time, if the amount of thermally excited electrons e ⁻ extracted per unit time (=current amount) is small, the diffusion of charge-transporting ion pairs can sufficiently catch up, so the duration of power supply tends to be longer. . In particular, if the amount of current is sufficiently small, semi-permanent power supply becomes possible. On the other hand, as the amount of thermally excited electrons e ⁻ taken out per unit time (=current amount) increases, the ions Y accumulate at the interface between the ion redox layer 21 and the charge-thermal excitation material layer 19, and the ions X are generated. As the amount of ions X decreases, the reaction of changing from ions X to ions Y becomes difficult to occur, ions X accumulate at the interface between the ion redox layer 21 and the positive electrode 15b, the amount of ions Y decreases, and ions Y change to ions X. It becomes difficult for changing reactions to occur. In this case, the duration of power generation tends to be short. However, the duration of power generation is determined not only by the current amount but also by the environmental temperature and the material composition of each layer of the heat-utilizing power generation element 13 (especially the material composition of the ion redox layer 21), so it is determined in advance. is difficult.

Such a decrease in the power generation capacity of the heat-utilization power generation element 13 (increased localization of ions in the ion redox layer 21 ) recovers over time by disconnecting the load L from the heat-utilization power generation element 13 . This is because reduction of the charge-transporting ion pair also stops when the movement of the thermally excited electron e ⁻ stops, so that only oxidation of the ion pair and diffusion of the charge-transporting ion pair proceed. However, the recovery time of the power generation capacity is also determined by the environmental temperature and the composition of the material of each layer of the heat-utilizing power generation element 13 (especially the composition of the material of the ion oxidation-reduction layer 21).

Returning to FIG. 1, the plurality of batteries 3a, 3b, 3c are electrically connected to the load L in parallel. Specifically, the positive electrode of the battery 3a is connected to one terminal of the load L via the switch 5a and the current sensor 9, and the negative electrode of the battery 3a is connected to the other terminal of the load L via ground. there is Similarly, the positive terminals of batteries 3b and 3c are connected to one terminal of load L via switches 5b and 5c and current sensor 9, and the negative terminals of batteries 3b and 3c are connected to load L via ground. is connected to the other terminal of the

The plurality of switches 5a, 5b, 5c are switching elements such as semiconductor switches, relay switches, etc. that turn on/off the electrical connection between their ends by external control. and the load L are provided on the connection path. That is, the switch 5a is provided on the connection path between the positive electrode of the battery 3a and one terminal of the load L, and turns ON/OFF the electrical connection between the battery 3a and the load L only. Similarly, the switches 5b and 5c are provided on the connection paths between the positive electrodes of the batteries 3b and 3c and one terminal of the load L, respectively, and are only electrically connected to the respective batteries 3b and 3c and the load L. on/off. These switches 5a, 5b, and 5c are configured to be switchable between on and off under the control of signals from the controller 11. FIG.

The voltage sensors 7a, 7b, 7c are sensors that are individually connected to both ends of the batteries 3a, 3b, 3c and independently detect the potential difference between the respective poles of the batteries 3a, 3b, 3c. These voltage sensors 7a, 7b, and 7c are capable of sending a signal indicating the detected potential difference to the controller 11. FIG.

The current sensor 9 is inserted into a connection path between one end of the parallel circuit of the batteries 3a, 3b, 3c on the side of the switches 5a, 5b, 5c and one terminal of the load L. , 3c to the load L is detected. The current sensor 9 is capable of sending a signal indicating the detected amount of current to the controller 11 .

The controller 11 refers to the values indicated by the signals sent from the voltage sensors 7a, 7b, 7c and the current sensor 9, and turns on the switches 5a, 5b, 5c based on the results of comparison between these values and specified values. It is a control device that controls on/off. The controller 11 is composed of an arithmetic unit such as a CPU responsible for arithmetic processing, a ROM and a RAM, etc., a memory unit for storing data referred to in the arithmetic processing or data generated by the arithmetic processing, and other components. Built-in communication unit etc. for exchanging signals with Power may be supplied to the controller 11 from a parallel circuit of the batteries 3a, 3b, and 3c, or from another supply source such as a secondary battery. The functions of the controller 11 will be described below.

FIG. 3 is a flow chart for explaining the control function of the switches 5a, 5b and 5c by the controller 11. As shown in FIG. In this way, the controller 11 determines the batteries 3a, 3b, and 3c whose potential differences are below the specified value based on the potential differences detected by the voltage sensors 7a, 7b, and 7c. switches 5a, 5b, and 5c in the ON state to the OFF state. At the same time, based on the potential differences detected by the voltage sensors 7a, 7b, and 7c, the controller 11 determines the batteries 3a, 3b, and 3c whose potential differences exceed the specified value, and determines the batteries 3a, 3b, and 3c. The switches 5a, 5b, and 5c in the off state are changed to the on state. At that time, the controller 11 performs control so that the switches 5a, 5b, and 5c that are in the off state among the switches 5a, 5b, and 5c corresponding to the plurality of batteries 3a, 3b, and 3c are alternately switched over time.

Specifically, when the operation of the controller 11 is started by a user's operation or the like, the controller 11 controls to turn on the switch 5a corresponding to the preset first battery 3a (step S01). . In response, the controller 11 detects the potential difference of the battery 3a that is currently supplying power to the load L based on the signal from the voltage sensor 7a (step S02). Next, the controller 11 determines whether or not the detected potential difference is equal to or less than a preset specified value VA (step S03). This specified value VA is based on the assumed environmental temperature, the composition of the material (especially the material of the ion oxidation-reduction layer 21) constituting the thermal power generation element 13 incorporated in the batteries 3a, 3b, and 3c, and the heat power generation element 13. It is set in advance according to at least one of the number of series and the input characteristics to the load, and corresponds to a value indicating a decrease in power generation capacity (increased localization of ions in the ion redox layer 21). When the controller 11 determines that the detected potential difference exceeds the specified value VA and the ions are not localized (step S03; NO), the controller 11 returns to the process of step S02, The processing of steps S02 and S03 is repeated for the battery 3a in operation.

On the other hand, when the controller 11 determines that the detected potential difference is equal to or less than the specified value VA and that the ions are localized (step S03; YES), the standby switch 5b corresponding to the OFF state switch 5b A potential difference of the battery 3b is detected based on a signal from the voltage sensor 7b (step S04). Then, the controller 11 determines whether or not the potential difference is equal to or greater than the specified value VB (step S05). This specified value VB is determined by the assumed environmental temperature, the composition of the material (especially the material of the ion oxidation-reduction layer 21) constituting the thermal power generation element 13 incorporated in the batteries 3a, 3b, and 3c, the It is set in advance according to at least one of the number of series and the input characteristics to the load, and corresponds to a value indicating recovery of power generation capacity (relaxation of localization of ions in the ion redox layer 21), and VB≧VA be. As a result of the determination, if it is determined that the value is less than the specified value VB and the localization of the ions has not been alleviated (step S05; NO), the controller 11 returns to step S04 and repeats detection and determination of the potential difference. .

On the other hand, when it is determined that the value is equal to or greater than the specified value VB and the localization of ions is relaxed (step S05; YES), the controller 11 turns off the switch 5a corresponding to the battery 3a in operation. and switch 5b corresponding to battery 3b on standby is turned on (step S06). After that, the process returns to step S02 to repeat the processing of steps S02 to S06, and the controller 11 sequentially replaces the batteries in operation, and controls the batteries in operation to transition to the standby state sequentially as time elapses.

FIG. 4 shows a timing chart showing the ON/OFF states of the switches 5a, 5b, and 5c that change over time under the control of the controller 11. (a) is the state of the switch 5a, and (b) is the state of the switch 5b. State, (c) shows the state of the switch 5c. In this way, under the control of the controller, the on-state periods _TON of the switches 5a, 5b, and 5c are sequentially switched over time, and the switches 5a, 5b, and 5c are sequentially switched to the off-state, and the off-state periods T _OFF is started sequentially. During the period _TOFF , the ions X and Y shown in FIG. 2 are sufficiently diffused and localized at the interface is eliminated.

Here, the controller 11 also has a function of controlling to change the number of batteries electrically connected to the load L based on the power supplied to the load L. FIG. FIG. 5 is a flowchart for explaining the function of changing the number of batteries by the controller 11. As shown in FIG. The processing shown in FIG. 5 is executed immediately before step S02 shown in FIG.

Specifically, when the operation of the controller 11 is started by a user's operation or the like, the controller 11 turns on the switch 5a corresponding to the preset first battery 3a (step S11). Next, the controller 11 detects the potential difference of the battery 3a that is currently supplying power to the load L and the current supplied to the load L based on the signals from the voltage sensor 7a and the current sensor 9. (step S12). Then, the controller 11 calculates the power value supplied to the load L based on the detected potential difference and current, and determines whether or not the power value is equal to or greater than the specified value WA (step S13). This specified value WA is set in advance according to the power consumption value of the load L. As shown in FIG. As a result of the determination, if the value is equal to or greater than the standard value (step S13; YES), the process proceeds to step S02 (FIG. 3) without changing the number of batteries connected to the load L, and the number of batteries in operation is reduced. Control replacement.

On the other hand, if it is less than the standard value (step S13; NO), in order to increase the number of batteries connected to the load L, the controller 11 switches the switch 5b corresponding to the next standby battery 3b. It is controlled to be turned on (step S14). As a result, the number of batteries electrically connected to the load L is two. After that, the controller 11 shifts the process to step S02 and performs control so that the batteries in operation are sequentially replaced with the batteries in standby.

FIG. 6 shows a timing chart showing the ON/OFF states of the switches 5a, 5b, and 5c that change over time under the control of the controller 11. (a) is the state of the switch 5a, and (b) is the state of the switch 5b. State, (c) shows the state of the switch 5c. In this way, when the number of batteries in operation is changed to two under the control of the controller, the number of batteries 3a, 3b, and 3c whose on-state periods T _ON overlap is always two. The switches 5a, 5b, 5c are controlled at the same time, the battery in operation is replaced with the battery in standby in sequence, and the off-state period _TOFF of the batteries 3a, 3b, 3c is changed to the period _TOFF of the other batteries in sequence. .

According to the heat utilization power generation module 1 according to the present embodiment, when power is supplied to the load L using the plurality of batteries 3a, 3b, and 3c electrically connected in parallel to the load L, The electrical connections between the batteries 3a, 3b, 3c and the load L can be switched at appropriate timing according to the individual power generation capabilities of the batteries 3a, 3b, 3c. Specifically, the localization of ions in the ion oxidation-reduction layer 21 in the heat-utilizing power generation element 13 is determined from the potential difference between the two electrodes of the battery 3a, 3b, and 3c, and the load is determined based on the determination result. The electrical connections with L are interchanged. As a result, while reducing the number of batteries, continuous power supply can be efficiently realized according to the magnitude of power supplied by each battery.

In particular, the controller 11 has a function of controlling the plurality of switches 5a, 5b, 5c so that the switch in the OFF state among the plurality of switches 5a, 5b, 5c is sequentially switched over time. As a result, the capacity of the batteries 3a, 3b, 3c whose power supply capacity has decreased is efficiently recovered. As a result, while reducing the number of batteries, continuous power supply can be realized more efficiently according to the magnitude of power supplied by each battery.

Further, the controller 11 has a function of changing the number of batteries electrically connected to the load L based on the power supplied to the load L from the parallel circuit of the batteries 3a, 3b, and 3c. As a result, the load L can be stably operated according to the power consumption necessary for the load L, and continuous and stable power supply can be reliably realized.

Having illustrated and described the principles of the invention in a preferred embodiment, it will be appreciated by those skilled in the art that the invention may be varied in arrangement and detail without departing from such principles. The invention is not limited to the specific configurations disclosed in this embodiment.

FIG. 7 is a circuit diagram showing the configuration of a heat-utilizing power generation module 1A according to a modification of the present invention. The difference of the structure of the heat-utilization power generation module 1A according to this modification from the heat-utilization power generation module 1 is that instead of the voltage sensors 7a, 7b, 7c provided corresponding to the respective batteries 3a, 3b, 3c, one The point is that the voltage sensor 7 is provided.

That is, the voltage sensor 7 is electrically connected to the positive electrodes of the batteries 3a, 3b, 3c via the switches 5a, 5b, 5c, and the voltage is applied across the load L from the parallel circuit of the batteries 3a, 3b, 3c. It is a sensor that detects a potential difference. The voltage sensor 7 is capable of sending a signal indicating the detected potential difference to the controller 11A.

The controller 11A has the same configuration as the controller 11, refers to the values indicated by the signals sent from the voltage sensor 7 and the current sensor 9, and operates the switch 5a based on the result of comparison between these values and a specified value. , 5b and 5c are turned on/off.

FIG. 8 is a flow chart for explaining the control function of the switches 5a, 5b, 5c by the controller 11A. In this way, the controller 11A determines the timing when the potential difference of the battery in operation falls below a specified value based on the potential difference detected by the voltage sensor 7, and turns on the battery in operation at that timing. The switches 5a, 5b, 5c are turned off, and the switches 5a, 5b, 5c corresponding to the standby batteries are turned on. At that time, the controller 11A performs control so that the switches 5a, 5b, and 5c that are in the OFF state are switched in order over time among the switches 5a, 5b, and 5c that correspond to the plurality of batteries 3a, 3b, and 3c.

Specifically, when the operation of the controller 11 is started by a user's operation or the like, the controller 11A controls to turn on the switch 5a corresponding to the preset first battery 3a (step S21). . In response, the controller 11A detects the potential difference of the battery 3a that is currently supplying power to the load L based on the signal from the voltage sensor 7 (step S22). Next, the controller 11A determines whether or not the detected potential difference is equal to or less than a preset specified value VA (step S23). When the controller 11A determines that the detected potential difference exceeds the specified value VA (step S23; NO), the controller 11A returns to the process of step S22 and performs the processes of steps S22 and S23 regarding the battery 3a in operation. repeat.

On the other hand, when the detected potential difference is equal to or less than the specified value VA (step S23; YES), the controller 11A turns off the switch 5a corresponding to the battery 3a in operation, and turns off the switch 5a corresponding to the battery 3b in standby. 5b is turned on (step S24). After that, the process returns to step S22 to repeat the processing of steps S22 to S24, and the controller 11A sequentially replaces the batteries in operation, and controls the batteries in operation to transition to the standby state sequentially as time passes. .

According to the above modification, at the timing when the potential difference applied to the load L from both electrodes of the plurality of batteries 3a, 3b, and 3c decreases, electrical connection with the load L among the plurality of batteries 3a, 3b, and 3c is cut off. The batteries used can be replaced sequentially. As a result, while reducing the number of batteries, continuous power supply can be efficiently realized according to the magnitude of power supplied by each battery. In addition, since the number of voltage sensors is reduced, it is advantageous for miniaturization, weight reduction, and improvement of switch control response.

DESCRIPTION OF SYMBOLS 1, 1A... Heat utilization electric power generation module, 3... Battery group, 3a, 3b, 3c... Battery, 5a, 5b, 5c... Switch, 7, 7a, 7b, 7c... Voltage sensor (voltage detection part), 9... Current sensor (current detection unit) 11, 11A controller (control unit) 13 thermal power generation element 15a negative electrode 15b positive electrode 17 electron transport layer 19 charge heat excitation material layer 21 ion redox Layer, L... load.

Claims (5)

A plurality of heat-utilizing power-generating batteries including the heat-utilizing power-generating element capable of heat-utilizing power generation, wherein the heat-utilizing power-generating element recovers the power-generating capacity by being disconnected from the load when the power-generating capacity declines, to the load . a group of batteries electrically connected in parallel with each other;
a plurality of switches provided on a connection path between each of the plurality of heat utilization power generation batteries and the load, for turning on/off electrical connection between each of the plurality of heat utilization power generation batteries and the load; ,
a voltage detection unit that detects a potential difference between both electrodes of the plurality of heat utilization power generation batteries;
Based on the comparison result between the potential difference detected by the voltage detection unit and a specified value, at least one of the plurality of switches in the ON state is changed to the OFF state, and at least one switch in the OFF state is changed to the OFF state. The plurality of switches are transitioned to an on state so that power is continuously supplied to the load by the plurality of thermal power generation batteries alternately supplying power to the load. and a control unit that controls the heat utilization power generation module. The voltage detection unit is configured to be capable of detecting a potential difference applied to the load from the plurality of heat utilization power generation batteries as the potential difference,
The control unit controls the plurality of switches such that, among the plurality of switches, switches in an off state are sequentially switched at timing when it is determined that the potential difference detected by the voltage detection unit is below a specified value. ,
The thermal power generation module according to claim 1. The voltage detection unit is configured to be capable of independently detecting the potential difference between both electrodes of each of the plurality of heat utilization power generation batteries,
The control unit is a switch corresponding to the heat utilization power generation battery determined that the potential difference detected by the voltage detection unit is below a specified value, and changes the switch from the ON state to the OFF state to change the voltage. A switch corresponding to the heat utilization power generation battery determined that the potential difference detected by the detection unit exceeds a specified value, the switch being in an OFF state transitioning to an ON state;
The thermal power generation module according to claim 1. The control unit controls the plurality of switches such that a switch in an off state among the plurality of switches is sequentially replaced over time.
The thermal power generation module according to any one of claims 1 to 3. further comprising a current detection unit that detects a current supplied from the plurality of heat-utilizing power generation batteries to the load,
The control unit controls the heat-utilizing power generation battery that is simultaneously electrically connected to the load based on the electric power corresponding to the potential difference detected by the voltage detection unit and the current detected by the current detection unit. controlling the plurality of switches to change the number of
The heat-utilizing power generation module according to any one of claims 1 to 4.

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