JP4867536B2 - Laminated electric double layer capacitor and voltage monitoring device thereof - Google Patents

Description

  In the present invention, a plurality of cells each having a separator sandwiched between a pair of activated carbon electrodes impregnated with an electrolytic solution are stacked via an intermediate electrode base material, and an inter-cell packing is interposed between these cells to collect current. The present invention relates to a multilayer electric double layer capacitor in which a cell laminate is formed by sandwiching a plate and an end plate and fastening with a fastening bolt, and the cell laminate is covered with a laminate of a laminate film, and a voltage monitoring device thereof.

A multilayer electric double layer capacitor shown in FIG. 6 is known. The multilayer electric double layer capacitor 101 includes a plurality of cells 105... 105 each having a separator 104 sandwiched between a pair of activated carbon electrodes 102 and 103 impregnated with an electrolytic solution. The first and second collector electrode plates 108a and 108b forming the anode and the cathode are disposed with the inter-cell packing 107 interposed between the cells 105 and 105, and the first and second collector plates 108a and 108b are disposed. It comprises a cell stack 111 in which two collector electrode plates 108a and 108b are sandwiched between first and second end plates 109a and 109b and tightened with a plurality of tightening bolts 110. (For example, patent document 1). A multilayer electric double layer capacitor in which the cell laminate 111 is covered with a laminate of a laminate film has also been developed.
JP 2003-217987 A

  By the way, the multilayer electric double layer capacitor in which the cell laminate is covered with a laminate film package generates a decomposition gas of the electrolyte from the inside of the cell when used at a high temperature for a long time. The inside of the package is filled, and the laminate of the laminate film expands. If it becomes like this, it will become difficult for the multilayer electric double layer capacitor to keep constant the applied pressure of the terminal cell held by the collector electrode plate and the end plate.

  Therefore, when the multilayer electric double layer capacitor is used for a long time, the pressure applied to the terminal cell is decreased, the internal resistance is increased, and the capacitance may be apparently reduced. As a result, FIG. As shown in FIG. 4, the shared voltage may not be kept constant. Further, when the above phenomenon further proceeds, there is a problem that the shared voltage of the cell located at the terminal end becomes extremely high, whereby the deterioration of the capacitor is promoted and the life may be shortened.

  Further, in the multilayer electric double layer capacitor in which the cell laminate 111 is covered with a laminate film package, as shown in FIG. 8, the lead wire 121 connected to the cell inside the package 113 is drawn out of the package 113. When pulling out from the portion 114 to the outside of the package 113, a gap δ is likely to occur between the inner peripheral surface of the conductor lead-out portion 114 and the outer peripheral surface of the conductor 121, and so-called gas leakage occurs in the lead-out portion 114. It is easy to generate. In addition, it is difficult to position and fix the conductor 121 inside the package body 113. If the conductor 121 is not positioned and fixed inside the package body 113, when the conductor 121 is pulled or pushed, the conductor lead-out is performed. The part 114 spreads and air leakage is more likely to occur.

  The purpose of the present invention is to connect a lead wire to the termination cell of the multilayer electric double layer capacitor, monitor the voltage abnormality of the capacitor, and if the voltage of the termination cell becomes abnormally high, the voltage adjusting resistor If the voltage of the terminal cell is not even when the voltage is reduced by using the voltage adjustment resistor, an abnormal heat is generated because the cell's shared voltage becomes uneven by issuing an alarm and calling attention. Another object of the present invention is to provide a voltage monitoring device for a multilayer electric double layer capacitor capable of preventing damage to a package body of a laminated film or damage to the entire device based on the above.

  Another object of the present invention is that the sealing property of the laminate film packaging body can be easily secured in the conductor lead-out portion, and the conductor wire is also attached to the laminate film inside the laminate film packaging body. An object of the present invention is to provide a multilayer electric double layer capacitor that can be easily positioned and fixed on the inner surface of a package.

According to the first aspect of the present invention, a plurality of cells each having a separator sandwiched between a pair of activated carbon electrodes impregnated with an electrolytic solution are laminated via a polarizing substrate, and inter-cell packing is interposed between these cells. A cell laminate is constituted by sandwiching between a collector electrode plate and an end plate and fastening with a fastening bolt, and the cell laminate is covered with a laminate film package ,
A conductive wire having a coating is connected to a terminal cell of the cell laminate, and the conductive wire is drawn out from a conductive wire lead-out portion of the laminate film packaging body, and an inner layer of the synthetic resin of the laminate film packaging body in the conductive wire lead-out portion In the multilayer electric double layer capacitor in which the coating of the conductive wire is welded ,
The outer layer of the conductive wire coating is formed of a synthetic resin compatible with the synthetic resin constituting the inner layer of the laminate film package,
The laminate film packaging body is based on aluminum foil, the outer layer is formed of polyethylene terephthalate, which is a crosslinkable resin, and the inner layer is formed of polyethylene, which is a thermal plastic resin,
In the coating of the conductive wire, the inner layer is formed of polyethylene containing glass fibers having heat resistance and flexibility, and the outer layer covering the inner layer is formed of acid-modified polyethylene .

The invention of claim 2, a voltage monitoring device for monitoring the voltage of the stacked electric double layer Kyappashita according to claim 1, the voltage detection resistor connected to the lead wires of the end of the cell, the collector electrode plate Two voltage dividing resistors having an arbitrary resistance value with a resistance ratio of 1 to be laminated between the current collecting terminals and a voltage dividing resistor having a resistance ratio of 1 among the two voltage dividing resistors. And a voltage comparison circuit that compares the voltage obtained from the voltage detection resistor with the average voltage of the obtained capacitor as a reference voltage.

The invention according to claim 3, in the voltage monitoring device of the stacked electric double layer capacitor according to claim 2, the voltage adjustment resistor having a resistance value set to approximately 1/5 against leakage resistance of the capacitor, the A switch for connecting a voltage adjusting resistor to the terminal cell is provided. When the voltage of the terminal cell is approximately 8% or more higher than the average voltage of the capacitor cell, the voltage adjusting resistor is inserted in the voltage comparison circuit. did.

According to a fourth aspect of the present invention, in the voltage monitoring device for the multilayer electric double layer capacitor according to the third aspect , the device operates when the voltage of the terminal cell is higher than the average voltage of the cell of the capacitor by about 15% or more. An alarm device was installed.

(1) The laminated electric double layer capacitor according to claim 1 is a composition in which a conductor wire connected to a terminal cell is drawn out from a conductor lead-out portion of a laminate of a laminate film, and the conductor lead-out portion constitutes the covering of the lead wire. Since the resin and the synthetic resin constituting the inner layer of the package are welded, the space between the conductor and the package can be sealed. In addition, the conductor can be positioned and fixed by welding the coating of the conductor and the inner layer of the package inside the package to protect the conductor and the lead-out portion.
In the laminated electric double layer capacitor according to claim 1 , the outer layer of the conductive wire coating is formed of a synthetic resin that is compatible with the synthetic resin constituting the inner layer of the laminate film package, so that the welding of the two is ensured. It is possible to prevent peeling of the welded portion.
In the laminated electric double layer capacitor according to claim 1 , the inner layer of the package is formed of polyethylene which is a thermal plastic resin, while the outer layer of the coating of the conductive wire is formed of acid-modified polyethylene. And the outer coating of the conducting wire can be reliably welded at a relatively low temperature.
(2) The voltage monitor device of the stacked electric double layer capacitor according to claim 2 can detect whether or not the voltage of the terminal cell is normal by comparing the average voltage of the terminal cell and the capacitor cell.
(3) According to the voltage monitor device of the stacked electric double layer capacitor of claim 3, when the voltage of the terminal cell becomes abnormally high, the voltage of the terminal cell can be lowered by the voltage adjusting resistor. . Thereby, the shared voltage of the cells can be made uniform. As a result, the life of the capacitor can be extended .
(4) When the voltage of the laminated electric double layer capacitor according to claim 4 is not equal to the voltage of the terminal cell even if the voltage adjusting resistor is used, an alarm is generated and attention is given. It is possible to prevent damage to the laminated film packaging body or damage to the entire apparatus due to abnormal heat generation caused by uneven cell sharing voltages .

  FIG. 1 is a sectional view of a multilayer electric double layer capacitor of the present invention. The multilayer electric double layer capacitor 1 includes a plurality of cells 5, 5... Sandwiched between a pair of activated carbon electrodes 2 and 3 impregnated with an electrolytic solution with a separator 4 interposed therebetween via an intermediate electrode substrate 6. A first collector plate 8a and a second collector plate 8b, which form an anode and a cathode, with an inter-cell packing 7 for preventing leakage of the electrolyte solution at the outer periphery between the cells 5 and 5 are provided. And arranging the first and second collector electrode plates 8a and 8b between the first and second end plates 9a and 9b and fastening them with a plurality of fastening bolts 10 to form a cell laminate 11, The cell laminate 11 is housed in a laminate film packaging 12. The intermediate electrode base material 6, the collector electrode plate 8a, and the end plate 9a are provided with first, second, and third gas vent holes 13, respectively. The first and second collector electrode plates 8a and 8b are provided with collector terminals 8c and 8d (see FIG. 4).

  In the multilayer electric double layer capacitor 1, a propylene carbonate (PC) solution of triethylmethylammonium tetrafluoroborate (TEMABF4) is used as the electrolytic solution. The pair of activated carbon electrodes 2 and 3 are formed as sheet electrodes using activated carbon as a main component, acetylene black as a conductive auxiliary agent, and Teflon (registered trademark) as a binder. The inter-cell packing 7 is formed of ethylene propylene rubber, the collector electrode plates 8a and 8b and the collector terminals 8c and 8d are formed of pure aluminum, and the intermediate electrode substrate 6 is formed of polyphenylene sulfide. ing. The package 12 is based on an aluminum foil 12a, the outer layer 12b is formed of polyethylene terephthalate, which is a crosslinkable resin, and the inner layer 12c is formed of polyethylene, which is a thermal plastic resin.

  As shown in FIG. 4, a plurality of conducting wires 20 are connected to the pair of terminal cells 5a and 5b so that the voltages of the terminal cells 5a and 5b can be detected. As shown in FIG. 3, these conducting wires 20 are covered with an inner layer 21a and an outer layer 21b. The inner layer 21a is formed of polyethylene containing glass fiber having heat resistance and flexibility, and the outer layer 21b is formed of acid-modified polyethylene. As shown in FIG. 2, the lead wire 20 drawn from the lead wire lead-out portion 22 of the package body 12 has a synthetic resin inner layer 12 c and the outer layer 21 b in the lead wire lead-out portion 22. The two are sealed by ultrasonic welding or heat welding. The inner layer 12c of the package 12 and the outer layer 21b of the conductor 20 are formed of compatible synthetic resin and do not easily peel off once welded. In particular, as shown in FIG. 5, if the outer layer 21 b of the conductor 20 and the inner layer 12 c of the package 12 are welded inside the package 12 on the inner side (cell side) than the conductor lead-out portion 22, Even when the bonding force between the two is strengthened and the conductor 20 is strongly pulled, the welded portion of the outer layer 21b of the conductor 20 and the inner layer 12c of the package 12 in the conductor lead-out portion 22 is protected and the two are sealed. It becomes possible to secure.

  FIG. 4 shows a voltage monitoring device for the multilayer electric double layer capacitor. The voltage monitoring device includes a voltage monitoring circuit 31 that monitors a voltage increase in the terminal cells 5a and 5b, and suppresses the voltage increase in the terminal cell when the voltage monitoring circuit 31 detects a voltage increase in the terminal cells 5a and 5b. And a voltage adjusting circuit 35.

  The voltage monitor circuit 31 has a resistance ratio (R1 + R2): R1 that is connected to the collector terminals 8c, 8d of the collector plates 8a, 8b of the multilayer electric double layer capacitor 1 and has a stacking number of one. Two voltage dividing resistors 33a and 33b having arbitrary resistance values, and voltage detection resistors 32a and 32b connected to the lead conductors 20a and 20b of the pair of terminal cells 5a and 5b drawn from the packaging body 12. And the voltage Vd obtained from the voltage detection resistors 32a and 32b with the average voltage per cell of the capacitor obtained from the voltage dividing resistors R1 and R1 having the resistance ratio 1 of the voltage dividing resistors 33a and 33b as the cell reference voltage Vs. Comparing comparators 34a and 34b are used. The voltage detection resistors 32a and 32b are set such that the comparators 34a and 34b output, for example, when the voltage of the terminal cells 5a and 5b increases to 8% or more. An OR circuit 38 that outputs a comparator output as an alarm output is connected to the comparators 34a and 34b.

  Further, the voltage adjustment circuit 35 is 1 for the leakage resistance of the capacitor connected between the current collecting terminal 8c and the lead conductor 20a and between the lead conductor 20b and the current collector terminal 8d (between the terminals of the cells 5a and 5b). The voltage adjusting resistors 36a and 36b having a resistance value set to / 5 and switches 37a and 37b that are turned on when the comparators 34a and 34b output are configured in series.

  In the voltage monitoring device, when the voltage of the terminal cells 5a and 5b becomes 8% or more, the comparators 34a and 34b output the switches 37a and 37b, and the voltage adjusting resistors 36a and 36b turn on the cells 5a and 5b. A voltage increase of 8% or more of the voltage is suppressed.

  The voltage monitor device is provided with a second voltage monitor circuit configured in the same manner as the voltage monitor circuit 31, and the voltage detection resistor of the second voltage monitor circuit is used, for example, the voltage of the terminal cell is a cell. By setting the comparator to output when the average voltage increases to 15% or more of the average voltage, the voltage of the terminal cell continues to rise in spite of the operation of the voltage adjustment circuit 35, and the cell average An alarm can be output when the voltage is 15% higher than the voltage.

Sectional drawing of the laminated | stacked electric double layer capacitor of this invention. Sectional drawing of a conducting wire extraction part. Sectional drawing of a conductor. The circuit diagram of the voltage monitoring apparatus of a multilayer type electric double layer capacitor. Sectional drawing of the other Example of a conducting wire extraction part. Sectional drawing of the laminated | stacked electric double layer capacitor of a prior art example. The shared voltage characteristic view of the multilayer electric double layer capacitor of the conventional example. Sectional drawing of the lead-wire extraction part of a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Laminated type electric double layer capacitor 2, 3 ... Activated carbon electrode 4 ... Separator 5 ... Cell 6 ... Intermediate electrode base material 7 ... Inter-cell packing 8a, 8b ... 1st, 2nd collector electrode plate 8c ... Current collection terminal 9a , 9b ... First and second end plates 10 ... Clamping bolts 11 ... Cell laminate 12 ... Laminated film packaging 12a ... Aluminum foil 12b ... Outer layer 12c ... Inner layer 20 ... Conductor 21a ... Inner layer 21b ... Outer layer (protective layer) )
DESCRIPTION OF SYMBOLS 22 ... Conductor extraction part 23 ... Resistance for voltage detection 31 ... Voltage monitor circuit 32 ... Resistance for voltage detection 33 ... Voltage dividing resistor 34 ... Comparator (voltage comparison circuit)
35 ... Voltage adjustment circuit 36 ... Voltage adjustment resistor 37 ... Switch 38 ... Alarm output part (OR circuit)

Claims (4)

A plurality of cells each having a separator sandwiched between a pair of activated carbon electrodes impregnated with an electrolyte solution are stacked via a polarizing substrate, and inter-cell packing is interposed between these cells to form a collector electrode plate and an end plate. A cell laminate is constructed by pinching and clamping with a clamping bolt, and the cell laminate is covered with a laminate film package ,
A conductive wire having a coating is connected to a terminal cell of the cell laminate, and the conductive wire is drawn out from a conductive wire lead-out portion of the laminate film packaging body, and an inner layer of the synthetic resin of the laminate film packaging body in the conductive wire lead-out portion In the multilayer electric double layer capacitor in which the coating of the conductive wire is welded ,
The outer layer of the conductive wire coating is formed of a synthetic resin compatible with the synthetic resin constituting the inner layer of the laminate film package,
The laminate film packaging body is based on aluminum foil, the outer layer is formed of polyethylene terephthalate, which is a crosslinkable resin, and the inner layer is formed of polyethylene, which is a thermal plastic resin,
A multilayer electric double layer capacitor characterized in that the coating of the conductive wire is made of polyethylene containing glass fiber having heat resistance and flexibility, and the outer layer covering the inner layer is made of acid-modified polyethylene. . 2. The voltage monitoring device for monitoring the voltage of the multilayer electric double layer capacitor according to claim 1, wherein the voltage detecting resistor connected to the lead-out conductor of the terminal cell and the current collecting terminal of the current collecting plate The average number of capacitors obtained by two voltage dividing resistors having an arbitrary resistance value with a resistance ratio of 1: 1 and a voltage dividing resistor having a resistance ratio of 1 among the two voltage dividing resistors. A voltage comparison circuit that compares a voltage obtained from the voltage detection resistor using a voltage as a reference voltage; and a voltage monitoring device for a multilayer electric double layer capacitor, comprising: A voltage adjusting resistor having a resistance value set to approximately 1/5 with respect to the leakage resistance of the capacitor; and a switch for connecting the voltage adjusting resistor to the terminal cell. 3. The voltage monitor device for a multilayer electric double layer capacitor according to claim 2, wherein the voltage adjusting resistor is inserted when the voltage of the terminal cell is higher by about 8% or more than the average voltage . 4. The voltage of the multilayer electric double layer capacitor according to claim 3, further comprising an alarm device that operates when a voltage of a terminal cell becomes higher by about 15% or more than an average voltage of the capacitor cell. Monitor device .

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