JP2021093333A - Charging device and charging method - Google Patents

Abstract

To provide a charging device and a charging method, capable of uniformly charging a plurality of power storage cells while reducing a charging time.SOLUTION: A charging device 100 comprises: a charger 110 for uniformly charging a plurality of power storage cells 50 so as to be connected to a module terminal of a power storage module 11; a charger 120 for individually charging each of the plurality of power storage cells 50 so as to be connected to each cell terminal of the plurality of power storage cells 50; and a control part 130 that controls the charger 110 and the charger 120 so as to charge a power with the charger 120 after the charging by the charger 110.SELECTED DRAWING: Figure 1

Description

The present invention relates to a charging device and a charging method.

Patent Document 1 describes a bipolar secondary battery. In this bipolar secondary battery, a bipolar electrode having a positive electrode layer formed on one surface and a negative electrode layer formed on the other surface of a current collector made of rectangular SUS foil is used, and the separator holds an electrolyte. It has a structure in which a plurality of sheets are arranged in series by stacking the electrolyte layers. In this bipolar secondary battery, a single battery layer is formed by a laminated structure in which an electrolyte layer is sandwiched between a positive electrode layer and a negative electrode layer. An exposed portion where SUS is exposed is formed on the current collector. Lead wires are electrically connected to the exposed portion using a conductive adhesive.

Japanese Unexamined Patent Publication No. 2008-117626

When charging the secondary battery as described above, for example, by using the current collectors of the cell cell layers located at both ends in the stacking direction as terminals, a plurality of cell cell layers can be charged at once. Can be considered. However, in this case, due to the manufacturing variation of the bipolar electrode, the voltage of each cell layer may vary, and as a result, the charging state of each cell layer may become non-uniform. On the other hand, when trying to charge each of the cell layers individually by using the lead wires provided in the exposed portion of the current collector constituting each of the cell layers, the maximum current depends on the resistance value of the lead wires. Since the value is limited, long-term charging is required.

Therefore, an object of the present invention is to provide a charging device capable of uniformly charging a plurality of storage cells while shortening the charging time, and a charging method.

The charging device according to the present invention is a charging device for charging a power storage module including a plurality of power storage cells stacked and connected in series with each other, and is connected to a module terminal of the power storage module to collectively combine the plurality of power storage cells. Charging by the first charger, the second charger connected to each cell terminal of the plurality of storage cells, and the second charger for individually charging each of the plurality of storage cells, and the first charger. A control unit for controlling the first charger and the second charger is provided so that charging by the second charger is performed after the above.

The charging method according to the present invention is a charging method for charging a power storage module including a plurality of power storage cells stacked and connected in series with each other, and a plurality of power storage cells are collectively used by using the module terminals of the power storage module. It is provided with a first step of charging the battery, and after the first step, a second step of individually charging each of the plurality of storage cells.

In these charging devices and charging methods, after charging a plurality of storage cells constituting the power storage module at once, each of the plurality of power storage cells is individually charged. Therefore, the storage cells can be charged evenly as compared with the case where a plurality of storage cells are only charged at once. In addition, the charging time can be shortened as compared with the case where each of the plurality of storage cells is only charged individually.

In the charging device according to the present invention, the control unit executes a first process of performing constant current charging by the first charger and a second process of charging by the second charger after the first process. May be good. In this way, the charging time can be surely shortened by using the constant current charging in the batch charging in which a relatively large current can easily flow.

In the charging device according to the present invention, the control unit executes a third process of performing constant voltage charging by the first charger after the first process, and when the current value becomes equal to or less than the threshold value in the third process. The third process may be completed and the second process may be executed. In this way, by shifting to individual charging using constant voltage charging after the current value falls below a certain level, the charging time can be shortened more reliably.

In the charging device according to the present invention, each of the plurality of storage cells is composed of a pair of bipolar electrodes laminated on each other and integrated by a sealing member, and the bipolar electrodes are the first surface and the first surface. It has an electrode plate including a second surface on the opposite side, a positive electrode layer formed on the first surface, and a negative electrode layer formed on the second surface, and cell terminals are provided on each of the electrode plates. It extends to the outside of the seal member, and the second charger may be connected to a portion of the cell terminal located outside the seal member. As described above, the cell terminals used for individual charging may be provided on each of the electrode foils of the bipolar electrodes constituting the storage cell.

According to the present invention, it is possible to provide a charging device and a charging method capable of uniformly charging a plurality of storage cells while shortening the charging time.

FIG. 1 is a schematic view showing a power storage module and a charging device according to the present embodiment. FIG. 2 is a graph showing changes in (a) voltage value and (b) current knowledge of each storage cell during charging. FIG. 3 is a graph showing changes in (a) voltage value and (b) current knowledge of each storage cell during charging.

Hereinafter, one embodiment will be described in detail with reference to the drawings. In the description of the drawings, the same or corresponding elements may be designated by the same reference numerals, and duplicate description may be omitted.

FIG. 1 is a schematic view showing a power storage module and a charging device according to the present embodiment. As an example, the power storage module 11 shown in FIG. 1 can be used as a part of a battery of various vehicles such as a forklift, a hybrid vehicle, and an electric vehicle. The power storage module 11 is a single battery having a substantially rectangular parallelepiped shape. The power storage module 11 is, for example, a secondary battery such as a nickel hydrogen secondary battery or a lithium ion secondary battery. The power storage module 11 may be an electric double layer capacitor. The power storage module 11 may be an all-solid-state battery.

Here, the power storage module 11 is a bipolar lithium ion secondary battery. The power storage module 11 is sandwiched between the positive electrode current collector plate 12 and the negative electrode current collector plate 13 in the stacking direction, and is electrically connected to the charger 110 described later via the positive electrode current collector plate 12 and the negative electrode current collector plate 13. Can be done.

The power storage module 11 includes a laminate (electrode laminate) 14 and a seal member 15. The laminate 14 has a plurality of bipolar electrodes 16, a plurality of separators 17, one positive electrode terminal electrode 18, and one negative electrode terminal electrode 19. The plurality of bipolar electrodes 16 are laminated with each other in one direction here. In the following, the stacking direction of the bipolar electrodes 16 may be simply referred to as the “stacking direction”. The laminated body 14 has side surfaces 14s along the laminating direction.

The positive electrode terminal electrode 18 is laminated on the bipolar electrode 16 at one end of the laminated body 14 in the stacking direction. The negative electrode terminal electrode 19 is laminated on the bipolar electrode 16 at the other end of the laminated body 14 in the stacking direction. The separator 17 is interposed between the adjacent bipolar electrodes 16, between the bipolar electrode 16 and the positive electrode termination electrode 18, and between the bipolar electrode 16 and the negative electrode termination electrode 19.

The bipolar electrode 16 has an electrode plate 21, a positive electrode layer (electrode layer) 22, and a negative electrode layer (electrode layer) 23. The electrode plate 21 includes a first surface 21a that intersects in the stacking direction and a second surface 21b on the opposite side of the first surface 21a. A positive electrode layer 22 is provided on the first surface 21a, and a negative electrode layer 23 is provided on the second surface 21b. That is, the electrode plate 21 is sandwiched between the positive electrode layer 22 and the negative electrode layer 23 along the stacking direction. In the bipolar electrode 16, a conductive plate having a positive electrode layer 22 formed on one surface and another conductive plate having a negative electrode layer 23 formed on one surface are formed between surfaces on which no electrode layer is formed. It may be formed by being superposed so as to be in contact with each other.

The electrode plate 21 is a foil-shaped conductive member and has a substantially rectangular shape. The electrode plate 21 is, for example, a metal foil or an alloy foil. The metal foil is, for example, a copper foil, an aluminum foil, a titanium foil, a nickel foil, or the like. The alloy foil is defined by, for example, a stainless steel foil (for example, SUS304, SUS316, SUS301, SUS304, etc. specified in JIS G 4305: 2015) and a plated steel sheet (for example, JIS G 3141: 2005). Cold-rolled steel sheet (SPCC, etc.)) Plated stainless steel sheet or alloy foil of the above metal. When the electrode plate 21 is an alloy foil, or when the electrode plate 21 is a metal foil other than the aluminum foil, the surface of the electrode plate 21 may be coated with aluminum. The thickness of the electrode plate 21 is, for example, 5 μm or more and 70 μm or less.

The positive electrode layer 22 is a layered member containing a positive electrode active material, a conductive auxiliary agent, and a binder, and has a substantially rectangular shape. The positive electrode active material of the present embodiment is, for example, a composite oxide, metallic lithium, sulfur and the like. The composition of the composite oxide includes, for example, at least one of iron, manganese, titanium, nickel, cobalt, and aluminum, and lithium. Examples of the composite oxide include olivine-type lithium iron phosphate (LiFePO4). The binder serves to anchor the active material or conductive auxiliary agent to the surface of the current collector and maintain the conductive network in the electrodes.

Examples of the binder include fluororesins such as polyvinylidene fluoride, polytetrafluoroethylene, and fluororubber, thermoplastic resins such as polypropylene and polyethylene, imide resins such as polyimide and polyamideimide, alkoxysilyl group-containing resins, and poly (poly). Examples thereof include acrylic resins such as meta) acrylic acid, styrene-butadiene rubber (SBR), carboxymethyl cellulose, sodium alginate, alginates such as ammonium alginate, water-soluble cellulose ester crosslinked products, and starch-acrylic acid graft polymers. it can. These binders may be used alone or in combination of two or more. The conductive auxiliary agent is, for example, acetylene black, carbon black, graphite or the like. The viscosity adjusting solvent is, for example, N-methyl-2-pyrrolidone (NMP) or the like.

The negative electrode layer 23 is a layered member containing a negative electrode active material, a conductive auxiliary agent, and a binder, and has a substantially rectangular shape. The negative electrode active material of the present embodiment is, for example, carbon such as graphite, artificial graphite, highly oriented graphite, mesocarbon microbeads, hard carbon, soft carbon, a metal compound, an element that can be alloyed with lithium or a compound thereof, and boron. Addition carbon etc. Examples of elements that can be alloyed with lithium include silicon and tin. As the conductive auxiliary agent and the binder, the same ones as those of the positive electrode layer 22 can be used.

The positive electrode terminal electrode 18 includes an electrode plate 21 and a positive electrode layer 22 formed on the first surface 21a of the electrode plate 21. In the positive electrode terminal electrode 18, an electrode layer such as a negative electrode layer 23 is not formed on the second surface 21b of the electrode plate 21. The positive electrode terminal electrode 18 is laminated on the bipolar electrode 16 so that the first surface 21a of the electrode plate 21 and the positive electrode layer 22 face the bipolar electrode 16 side (inside the laminated body 14).

The negative electrode terminal electrode 19 includes an electrode plate 21 and a negative electrode layer 23 formed on the second surface 21b of the electrode plate 21. In the negative electrode terminal electrode 19, an electrode layer such as a positive electrode layer 22 is not formed on the first surface 21a of the electrode plate 21. The negative electrode terminal electrode 19 is laminated on the bipolar electrode 16 so that the second surface 21b of the electrode plate 21 and the negative electrode layer 23 face the bipolar electrode 16 side (inside the laminated body 14).

The separator 17 is a layered member interposed between the adjacent bipolar electrodes 16, between the bipolar electrode 16 and the positive electrode terminal electrode 18, and between the bipolar electrode 16 and the negative electrode terminal electrode 19, and has a substantially rectangular shape. ing. The separator 17 is a member that prevents a short circuit between the adjacent bipolar electrodes 16, between the bipolar electrode 16 and the positive electrode terminal electrode 18, and between the bipolar electrode 16 and the negative electrode terminal electrode 19. The separator 17 is composed of the electrolyte contained in the positive electrode layer 22 and the negative electrode layer 23. When the separator 17 is composed of a solid electrolyte, it may have a substantially rectangular plate shape.

The separator 17 is a porous film made of a polyolefin resin such as polyethylene (PE) or polypropylene (PP). The separator 17 may be a woven fabric or a non-woven fabric made of polypropylene, methyl cellulose or the like. The separator 17 may be reinforced with a vinylidene fluoride resin compound.

The seal member 15 is a member that holds a plurality of bipolar electrodes 16, a plurality of separators 17, a positive electrode terminal electrode 18, and a negative electrode terminal electrode 19 included in the laminated body 14, and has insulating properties. More specifically, the sealing member 15 holds an electrode plate 21 constituting a bipolar electrode 16, a positive electrode terminal electrode 18, and a negative electrode terminal electrode 19. The sealing member 15 seals the side surface 14s of the laminated body 14.

The seal member 15 has an outer frame shape (here, a rectangular frame shape) that follows the outer shape of the electrode plate 21 when viewed from the stacking direction, and the electrode plates adjacent to each other in the stacking direction at the outer edge portion 21c of the electrode plate 21. It is intervened between 21. The sealing member 15 interposed between the electrode plates 21 is joined (for example, welded) to the first surface 21a at the outer edge portion 21c of the electrode plate 21. The seal member 15 may be further joined (for example, welded) to the second surface 21b of the electrode plate 21, or the seal members 15 may be joined to each other (for example, welded).

On the other hand, the seal member 15 is also arranged at one end of the laminated body 14 in the laminating direction on the second surface 21b of the electrode plate 21 of the positive electrode terminal electrode 18 facing the outside of the laminated body 14, and is also arranged on the second surface 21b. It is joined (for example, welded). Further, the sealing member 15 is arranged on the first surface 21a facing the outside of the laminated body 14 of the electrode plate 21 of the negative electrode terminal electrode 19, and is joined (for example, welded) to the first surface 21a.

The positive electrode current collector plate 12 is arranged in the region surrounded by the seal member 15 on the second surface 21b of the electrode plate 21 of the positive electrode terminal electrode 18 when viewed from the stacking direction. That is, the seal member 15 is arranged at one end of the laminated body 14 in the laminating direction so as to surround the positive electrode current collector plate 12 when viewed from the laminating direction. Further, when viewed from the stacking direction, the negative electrode current collector plate 13 is arranged in the region surrounded by the seal member 15 on the first surface 21a of the electrode plate 21 of the negative electrode terminal electrode 19. That is, the seal member 15 is arranged at the other end of the laminated body 14 in the laminating direction so as to surround the negative electrode current collector plate 13 when viewed from the laminating direction.

The material that forms the seal member 15 is a resin member or the like that exhibits heat resistance. Examples of the resin member exhibiting heat resistance include polyimide, polypropylene (PP), polyphenylene sulfide (PPS), modified polyphenylene ether (modified PPE), PA66 and the like.

An electrolytic solution (not shown) is housed in the space (region surrounded by the seal member 15 and the electrode plate 21) S sealed by the seal member 15. Examples of the electrolytic solution include cyclic carbonates, cyclic esters, chain carbonates, chain esters, ethers and the like. The supporting salt contained in the electrolytic solution is, for example, a lithium salt. Lithium salts are, for example, LiBF ₄ , LiPF ₆ , LiN (FSO ₂ ) ₂ , LiN (SO ₂ CF ₃ ) ₂ , LiN (SO ₂ C ₂ F ₅ ) ₂ , or a mixture thereof.

Here, in the power storage module 11, one power storage cell 50 is composed of a pair of electrode plates 21 adjacent to each other. That is, the power storage module 11 includes a plurality of power storage cells 50 that are stacked on each other and connected in series. Each of the plurality of storage cells 50 is composed of a pair of bipolar electrodes 16 and the like that are laminated on each other and integrated by a sealing member 15. Then, in the power storage module 11, each of the power storage cells 50 can be electrically connected to the charger 120, which will be described later.

More specifically, a plate-shaped (foil-shaped) conductive member 24 (for example, a lead wire) is joined to and integrated with the outer edge portion 21c of the electrode plate 21 such as the bipolar electrode 16, and the conductive member 24 is integrated. Projects outward from the outer surface 15s along the side surface 14s of the seal member 15. That is, the conductive member 24 is a cell terminal provided on each of the electrode plates 21 and extending to the outside of the seal member 15. Each of the storage cells 50 may be connected to the charger 120 via the conductive member 24. A part of the current collector plate (electrode plate 21) may protrude outward from the outer surface 15s along the side surface 14s of the seal member 15 to be configured as a cell terminal without joining the conductive member 24.

On the other hand, in the power storage module 11, the positive electrode current collector plate 12 and the negative electrode current collector plate 13 function as module terminals that enable collective electrical connection of the plurality of power storage cells 50. Here, the bipolar electrode 16 and the like mean the bipolar electrode 16, the positive electrode terminal electrode 18, and the negative electrode terminal electrode 19.

Subsequently, the charging device 100 shown in FIG. 1 will be described. The charging device 100 includes a charger (first charger) 110, a plurality of chargers (second charger) 120, and a control unit 130. The charger 110 is electrically connected to each of the positive electrode current collector plate 12 and the negative electrode current collector plate 13 as module terminals of the plurality of storage cells 50. As a result, the charger 110 can collectively charge the plurality of storage cells 50 constituting the power storage module 11.

The charger 120 is electrically connected to each of the conductive members 24 as cell terminals of the plurality of storage cells 50. The charger 120 is connected to a portion of the conductive member 24 located outside the seal member 15. As a result, the charger 120 can individually charge each of the plurality of storage cells 50 constituting the power storage module 11. The control unit 130 controls charging using the charger 110 and charging using the charger 120.

Therefore, the control unit 130 is at least electrically connected to the charger 110 and the charger 120, and can acquire information indicating the charging state such as the voltage of the storage cell 50. Therefore, in addition to the two wirings for charging by the charger 120, two wirings for measuring the voltage of the storage cell 50 and the like can be provided for each of the conductive members 24. The control unit 130 may be integrally configured with the charger 110 or the charger 120, or may be configured separately from the charger 110 and the charger 120.

The control unit 130 is a computer including a CPU (Central Processing Unit), a RAM (Random Access Memory) as a main storage device, a ROM (Read Only Memory), a communication module as a data transmission / reception device, an output device, an input device, and the like. Can be configured as a system. The following processing of the control unit 130 is performed by loading a predetermined program on hardware such as a CPU and RAM to operate a communication module, an output device, an input device, and the like under the control of the CPU. It can be realized by reading and writing data in RAM or the like.

The following charging by the charging device 100 can be performed, for example, as a conditioning step of the power storage module 11. The conditioning step is a step of first charging the power storage module 11 to a fully charged state (first charge). In the conditioning step, each of the storage cells 50 is not charged evenly, and when the storage cell 50 with a low voltage is generated, the SEI (Solid Electrolyte Interface) coating is uniformly applied to the storage cell 50 in the subsequent aging step. It may be difficult to form. Therefore, the charging device 100 charges the power storage module 11 as follows.

That is, the charger 110 and the charger 120 so that the control unit 130 collectively charges the plurality of storage cells 50 by the charger 110 and then individually charges the plurality of storage cells 50 by the charger 120. To control. More specifically, first, the control unit 130 executes a process (first process) A in which the charger 110 collectively charges the plurality of storage cells 50 with a constant current. 2 and 3 are graphs showing changes in (a) voltage value and (b) current knowledge of each storage cell during charging. As shown in FIG. 2, here, the process A collectively charges the plurality of storage cells 50 with a constant current while setting the current value (charging current) IA to a constant value Ia.

As a result, the voltage value of each of the storage cells 50 rises. However, due to the variation in capacity generated during the manufacture of the storage cell 50, the change in the voltage value of the storage cell 50 also varies. Here, among the plurality of storage cells 50, the voltage values VA, VB, and VC of the three storage cells 50A, 50B, and 50C having different voltage changes are illustrated (the storage cells 50A, 50B, and 50C are not shown).

The control unit 130 ends the process A at the time when the voltage value VA of the storage cell 50A having the largest change (increasing rate) reaches the specified voltage value Va, and at the same time, the charger 110 collectively performs the plurality of storage cells 50. The process (third process) B for performing the constant voltage charging is executed. Here, the process B performs batch constant voltage charging of the plurality of storage cells 50 with the respective voltage values VA, VB, and VC at the time point ta. As a result, the current value IA decreases as the charge amount of the storage cell 50 increases.

After that, as shown in FIGS. 2 and 3, the control unit 130 ends the process B at the time tb when the current value IA decreases from the constant value Ia to the threshold value Ib or less, and at the same time, the plurality of storage cells 50 by the charger 120 are used. The process (second process) C for individually charging each of the above is executed. At the start of the process C, all of the plurality of storage cells 50 are charged with the current value (for example, the threshold value Ib) at the time when the process B is completed. The current value at the start of process C is smaller than the current value at the start of process A.

In this process C, the storage cell 50A that has already reached the specified voltage value Va is continuously charged at the voltage value Va at a constant voltage from the process B. On the other hand, in the process C, the storage cells 50B and 50C that have not yet reached the specified voltage value Va are charged with a constant current at the current value (for example, the threshold value Ib) at the time tb at the end of the process B.

Therefore, after the process C is started, the current value IA of the storage cell 50A continues to decrease, but for the storage cells 50B and 50C, the current values IB and IC are constant at, for example, the threshold value Ib, and are respectively. The voltage values VB and VC of are increased. After that, the control unit 130 switches the charging method of the storage cells 50B to constant voltage charging at tk when the voltage values VB of the storage cells 50B and 50C reach the specified voltage value Va.

Further, the control unit 130 switches the charging method of the storage cell 50C to constant voltage charging at the time td when the voltage value VC of the storage cell 50C reaches the specified voltage value Va. That is, in the process C, the control unit 130 switches the charging method from the constant current charging to the constant voltage charging in order from the one in which the voltage value among the plurality of storage cells 50 reaches the specified voltage value Va. After that, the control unit 130 ends charging by the charger 120 in order from the storage cell 50 that is in the fully charged state.

As described above, the control unit 130 uses the positive electrode current collector plate 12 and the negative electrode current collector plate 13, which are the module terminals of the power storage module 11, to collectively charge a plurality of power storage cells 50 in the first step (process A). ), And after the first step, a charging method including a second step of individually charging each of the plurality of storage cells 50 using the conductive member 24 which is a cell terminal of each of the plurality of storage cells 50. It will be implemented.

As described above, in the charging device 100 and the charging method thereof according to the present embodiment, after charging the plurality of storage cells 50 constituting the power storage module 11 at once, each of the plurality of power storage cells 50 is individually charged. Charge. Therefore, the charging time can be shortened as compared with the case where each of the plurality of storage cells 50 is only charged individually. Further, the storage cells 50 can be charged evenly as compared with the case where a plurality of storage cells 50 are only charged at once.

Further, in the charging device 100, the control unit 130 executes a process A of performing constant current charging by the charger 110 and a process C of charging by the charger 120 after the process A. In this way, the charging time is surely shortened by using constant current charging for batch charging, which makes it easy to pass a relatively large current, and using constant voltage charging for individual charging, which makes it difficult for a relatively large current to flow. However, even charging is possible.

Further, in the charging device 100, the control unit 130 executes the process B of performing constant voltage charging by the charger 110 after the process A, and ends the process B when the current value becomes equal to or less than the threshold value in the process B. Then, process C is executed. In this way, by shifting to individual charging using constant voltage charging after the current value falls below a certain level, the charging time can be shortened more reliably.

The above embodiments have described one aspect of the present invention. Therefore, the present invention can be arbitrarily modified without being limited to the above embodiment.

For example, in the above embodiment, the control unit 130 performs constant current charging in process A, constant voltage charging in process B, and constant current charging and constant voltage charging in process C. The charging method in is not limited to these examples.

Further, in the above embodiment, the current value at the end of collective charging of the plurality of storage cells 50 by the charger 110 and the current value at the start of each individual charging of the plurality of storage cells 50 by the charger 120. Gave a continuous example. However, when the control unit 130 switches from the collective charging of the plurality of storage cells 50 by the charger 110 to the individual charging of the plurality of storage cells 50 by the charger 120, the current value is set to the resistance of the conductive member 24. The current value may be discontinuously changed (decreased) according to the value.

In this case, the process B between the process A and the process C may be omitted. That is, after the constant current charging is performed in the process A, the process C can be executed while the current value is discontinuously reduced to the current value corresponding to the resistance value of the conductive member 24.

11 ... power storage module, 12 ... positive electrode current collector plate (module terminal), 13 ... negative electrode current collector plate (module terminal), 15 ... seal member, 16 ... bipolar electrode, 21 ... electrode plate, 21a ... first surface, 21b ... Second surface, 22 ... positive electrode layer, 23 ... negative electrode layer, 24 ... conductive member (cell terminal), 50 ... storage cell, 100 ... charging device, 110 ... charger (first charger), 120 ... charger (first) 2 charger), 130 ... Control unit.

Claims (5)

A charging device for charging a power storage module including a plurality of power storage cells stacked and connected in series with each other.
A first charger connected to the module terminal of the power storage module and for charging the plurality of power storage cells at once, and
A second charger connected to each cell terminal of the plurality of storage cells and for individually charging each of the plurality of storage cells.
A control unit that controls the first charger and the second charger so that charging by the second charger is performed after charging by the first charger.
A charging device equipped with. The control unit
The first process of performing constant current charging with the first charger and
After the first process, the second process of charging by the second charger and
To execute,
The charging device according to claim 1. The control unit executes a third process of performing constant voltage charging by the first charger after the first process, and when the current value becomes equal to or less than a threshold value in the third process, the third process. Is completed and the second process is executed.
The charging device according to claim 2. Each of the plurality of storage cells is composed of a pair of bipolar electrodes laminated on each other and integrated by a sealing member.
The bipolar electrode includes an electrode plate including a first surface and a second surface opposite to the first surface, a positive electrode layer formed on the first surface, and a negative electrode layer formed on the second surface. Have and
The cell terminals are provided on each of the electrode plates and extend to the outside of the sealing member.
The second charger is connected to a portion of the cell terminal located outside the seal member.
The charging device according to any one of claims 1 to 3. It is a charging method for charging a power storage module including a plurality of power storage cells stacked and connected in series with each other.
The first step of collectively charging the plurality of storage cells using the module terminals of the power storage module, and
After the first step, a second step of individually charging each of the plurality of storage cells, and
Charging method with.

Images