Electrochemical cells and electrochemical cell modules

Abstract

To provide an electrochemical cell, the life-span of which is extended, and an electrochemical cell module.SOLUTION: An electrochemical cell 50 includes: a first single cell 1 that has a first power generation element 2 and a first package 3 having the first power generation element on the inside; a second single cell 11 that has a second power generation element 12 and a second package 13 having the second power generation element on the inside; and an outer container 4 that has the first and second single cells on the inside. The electrochemical cell has an electrolyte 18 located within the first package, within the second package, and between the first and second packages. At least either the first package or the second package has an opening 15. Dimensions of the opening are a length of 10-200 mm and a width of 10-50 mm.SELECTED DRAWING: Figure 8

Description

[Technical Field]

[0001] The present disclosure relates to electrochemical cells and electrochemical cell modules. [Background technology]

[0002] Conventionally, an electrochemical cell module has been proposed, for example, as disclosed in Patent Document 1. The electrochemical cell module disclosed in Patent Document 1 can operate electrochemical cells uniformly and stably, and can suppress defects such as capacity reduction and gas generation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-21382 Summary of the Invention

[0004] The electrochemical cell of the present disclosure includes a first unit cell, a second unit cell, an outer container, and a liquid layer. The first unit cell has a first power generating element and a first packaging body having the first power generating element inside. The second unit cell has a second power generating element and a second packaging body having the second power generating element inside. The outer container has the first unit cell and the second unit cell inside. The liquid layer is located between the first packaging body and the second packaging body and is in direct contact with the first packaging body and the second packaging body.

[0005] The electrochemical cell of the present disclosure includes a first unit cell, a second unit cell, and an outer container. The first unit cell has a first power generating element and a first packaging body having the first power generating element inside. The second unit cell has a second power generating element and a second packaging body having the second power generating element inside. The outer container has the first unit cell and the second unit cell inside. An electrolyte is located inside the first packaging body, inside the second packaging body, and between the first packaging body and the second packaging body.

[0006] The electrochemical cell module of the present disclosure includes the above-described electrochemical cell, a housing that houses the electrochemical cell, and a mechanism that pressurizes the first unit cell and the second unit cell.

[0007] The electrochemical cell module of the present disclosure includes the electrochemical cell described above and a housing that has the electrochemical cell therein. The housing applies pressure to the first unit cell and the second unit cell. [Brief explanation of the drawings]

[0008] The objects, features, and advantages of the present disclosure will become more apparent from the following detailed description and drawings. [Figure 1] FIG. 1 shows a perspective view of an electrochemical cell module. [Figure 2] 2 shows a cross-sectional view taken along the line II-II in FIG. [Figure 3] 3 shows an enlarged view of region III in FIG. 2. [Figure 4] 3 shows a cross-sectional view corresponding to FIG. 2 of another example of an electrochemical cell module. [Figure 5] 3 shows a cross-sectional view corresponding to FIG. 2 of yet another example of an electrochemical cell module. [Figure 6] 3 shows a cross-sectional view corresponding to FIG. 2 of yet another example of an electrochemical cell module. [Figure 7] 3 shows a cross-sectional view corresponding to FIG. 2 of another example of an electrochemical cell module. [Figure 8] 10 shows a cross-sectional view corresponding to FIG. 2 of yet another example of an electrochemical cell module. [Figure 9] 10 shows a cross-sectional view corresponding to FIG. 2 of yet another example of an electrochemical cell module. DETAILED DESCRIPTION OF THE INVENTION

[0009] The electrochemical cell module 100 will be described in detail with reference to FIGS. 1 and 2. As shown in FIGS. 1 and 2, the electrochemical cell module 100 includes a housing 5 and an electrochemical cell 50 located within the housing 5. The electrochemical cell 50 is a component that functions as a battery within the electrochemical cell module 100. The electrochemical cell 50 includes, for example, a lithium-ion battery. The electrochemical cell 50 includes an outer container 4, a first unit cell 1 and a second unit cell 11 located within the outer container 4, and a liquid layer 14 located between the first unit cell 1 and the second unit cell 11. The first unit cell 1 and the second unit cell 11 may be held, for example, by pressing their main surfaces against each other. Within the electrochemical cell 50, the first unit cell 1 and the second unit cell 11 may be stacked, for example. The electrochemical cell 50 is, for example, plate-shaped. The electrochemical cell 50 can be electrically connected to an external device to pass electricity to the external device.

[0010] The first cell 1 has a first power generating element 2, a first packaging body 3 having the first power generating element 2 therein, and a first terminal. The first cell 1 is the smallest unit member that functions as a battery within the electrochemical cell 50. The first cell 1 is, for example, in the shape of a plate having a main surface. The first cell 1 may also be, for example, circular. The first cell 1 may also be, for example, rectangular when viewed from a direction perpendicular to the main surface of the first cell 1. The dimensions of the first cell 1 may be, for example, 50 mm to 500 mm in length, 50 mm to 300 mm in width, and 0.1 mm to 2 mm in thickness.

[0011] The first power generating element 2 is a component for storing and discharging electricity using an electrochemical reaction. The first power generating element 2 includes, for example, a positive electrode, a negative electrode, and a separator between the positive electrode and the negative electrode. The first power generating element 2 can exchange cations and anions between the positive electrode and the negative electrode via the separator. The first power generating element 2 can pass electricity to an external device by electrically connecting the positive electrode and the negative electrode to the external device.

[0012] The first power generating element 2 is, for example, a stack of a positive electrode, a separator, and a negative electrode. The first power generating element 2 is, for example, in the shape of a plate. The first power generating element 2 is, for example, a stack of a positive electrode, a separator, and a negative electrode in the thickness direction of the plate.

[0013] The positive and negative electrodes may be, for example, electrochemically active materials. The positive and negative electrodes may include, for example, an active material and an electrolyte. The electrolyte may be, for example, a solvent or a solvent mixture to which a salt has been added.

[0014] Specifically, the positive and negative electrodes may be made of the active materials and electrolytes described in U.S. Provisional Patent Application No. 61 / 787,382 entitled "Semi-Solid Electrodes Having High Rate Capability" and U.S. Provisional Patent Application No. 61 / 787,372 entitled "Asymmetric Battery Having a Semi-Solid Cathode and High Energy Density Anode." The positive and negative electrodes may contain, for example, additives.

[0015] The separator is a member provided to prevent short-circuiting between the positive electrode and the negative electrode. The separator may have, for example, fine holes through which cations and anions pass. The separator may be made of, for example, a porous insulating material. Specifically, the separator may be made of, for example, polyolefin or polyvinyl chloride.

[0016] When the first power generating element 2 is in the form of a plate, it can be set to, for example, a length of 50 mm to 500 mm, a width of 50 mm to 300 mm, and a thickness of 0.1 mm to 2.0 mm.

[0017] The first packaging body 3 is a member having a space for enclosing the first power generating element 2 inside. The first packaging body 3 is provided to protect the first power generating element 2 from the external environment. More specifically, the first packaging body 3 is provided to electrically insulate the first power generating element 2 from the external environment. The first packaging body 3 is provided so as to cover the entire first power generating element 2.

[0018] The first packaging body 3 has, for example, a flat bag shape. The first packaging body 3 is formed, for example, by forming a laminate film into a flat bag shape. The first packaging body 3 may also be formed, for example, by welding two laminate films. The first packaging body 3 may have, for example, a rectangular shape when viewed from the stacking direction of the positive electrode, separator, and negative electrode.

[0019] The first packaging body 3 includes, for example, an insulating material. This prevents a short circuit between the external environment and the first power generating element 2 via the first packaging body 3, and the first packaging body 3 can protect the first power generating element 2 from the external environment. The first packaging body 3 includes, for example, a resin material. More specifically, the resin material may be, for example, polyethylene terephthalate or polyethylene.

[0020] Furthermore, the first packaging body 3 may have, for example, a multi-layer structure. Specifically, the first packaging body 3 includes, for example, a thermally adhesive resin material and a heat-resistant resin material. Specifically, the thermally adhesive resin material is a resin material whose melting temperature is lower than 150°C. Specifically, the heat-resistant resin material is a resin material whose melting temperature is 150°C or higher and 300°C or lower. For example, polyethylene terephthalate or polyethylene naphthalate can be used as the heat-resistant resin material. For example, polyethylene or polypropylene can be used as the thermally adhesive resin material.

[0021] The first terminal is provided to electrically connect the first power generating element 2 to an external device. The first terminal is, for example, plate-shaped. Specifically, the first terminal is, for example, quadrangular when viewed from the stacking direction of the first unit cell 1 and the second unit cell 11. The first terminal may be, for example, rectangular. The rectangular shape may have, for example, long sides and short sides.

[0022] When viewed from the stacking direction of the first unit cell 1 and the second unit cell 11, the first terminal is in contact with the first power generating element 2. When viewed from the stacking direction of the first unit cell 1 and the second unit cell 11, the first terminal is located on one of the sides of the outer periphery of the first power generating element 2. Furthermore, the first terminal extends outward from the first unit cell 1 in order to be electrically connected to an external device. Furthermore, the first terminal is electrically connected to an external connection terminal outside the first unit cell 1.

[0023] The first terminal has, for example, a conductive member. The first terminal may have, for example, a metal material. More specifically, the metal material may be, for example, aluminum or copper. When the first terminal has a plate shape, it may have, for example, a length of 30 mm to 100 mm, a width of 10 mm to 100 mm, and a thickness of 0.1 mm to 0.5 mm.

[0024] The second unit cell 11, like the first unit cell 1, is provided to store electricity. In the electrochemical cell 50, the first unit cell 1 and the second unit cell 11 are connected in parallel. This allows the capacity of the electrochemical cell 50 to be increased. Alternatively, the first unit cell 1 and the second unit cell 11 may be connected in series. This allows the voltage of the electrochemical cell 50 to be increased.

[0025] The second unit cell 11 and the first unit cell 1 are stacked, for example, in the outer container 4. The second unit cell 11 includes a second power generating element 12, a second packaging body 13, and a second terminal. In the electrochemical cell 50, the second unit cell 11 has the same shape as the first unit cell 1. However, the second unit cell 11 may have, for example, a shape different from that of the first unit cell 1. In the electrochemical cell 50, the second unit cell 11 is stacked with the outer periphery aligned with the first unit cell 1. Note that the second unit cell 11 may be stacked with the outer periphery not aligned with that of the first unit cell 1.

[0026] The first power generating element 2 and the second power generating element 12 are stacked with their long sides and short sides aligned when viewed from the stacking direction of the first unit cells 1 and the second unit cells 11. The first packaging body 3 and the second packaging body 13 are stacked with their long sides and short sides aligned when viewed from the stacking direction of the first unit cells 1 and the second unit cells 11. The first terminal and the second terminal are stacked with their long sides and short sides aligned when viewed from the stacking direction of the first unit cells 1 and the second unit cells 11.

[0027] The second power generating element 12 may be made of, for example, the same material as that used for the first power generating element 2. More specifically, the second power generating element 12 may be made of the same material as that used for the first power generating element 2. Alternatively, the second power generating element 12 may be made of, for example, a different material from that used for the first power generating element 2.

[0028] The second packaging body 13 has the same shape as the first packaging body 3. However, the second packaging body 13 may have a different shape from the first packaging body 3, for example. For the second packaging body 13, for example, the same material as that used for the first packaging body 3 may be used. More specifically, the second packaging body 13 may be made of the same material as the first packaging body 3. Furthermore, for example, the second packaging body 13 may be made of a different material from that used for the first packaging body 3.

[0029] The second terminal has the same shape as the first terminal. However, the second terminal may have a different shape from the first terminal, for example. The second terminal may be made of the same material as the first terminal, for example. More specifically, the second terminal may be made of the same material as the first terminal. Furthermore, the second terminal may be made of a different material than the first terminal, for example.

[0030] The second unit cell 11 can be set to have the same dimensions as the first unit cell 1, for example. Alternatively, the second unit cell 11 may have dimensions different from those of the first unit cell 1, for example.

[0031] The outer container 4 is a member having a space for enclosing the first unit cell 1 and the second unit cell 11. The outer container 4 is a member for protecting the first unit cell 1 and the second unit cell 11 from the external environment. More specifically, the outer container 4 is a member for protecting the first unit cell 1 and the second unit cell 11 from oxygen and moisture in the air.

[0032] The outer container 4 may have, for example, a cylindrical shape. The outer container 4 may also have, for example, a rectangular parallelepiped shape. The outer container 4 may also have, for example, a bag shape. The outer container 4 may be formed, for example, by forming one member into a bag shape. The outer container 4 may also be formed, for example, by welding two members together. The outer container 4 may have a rectangular shape when viewed from the stacking direction of the first unit cell 1 and the second unit cell 11. The outer container 4 may be configured so that pressure applied from the outside by a pressurizing mechanism, as described below, is transmitted to the inside of the outer container 4.

[0033] The outer container 4 includes, for example, an insulating material. This reduces the possibility of a short circuit between the external environment and the first unit cell 1 or the second unit cell 11 through the outer container 4, and the outer container 4 can protect the first unit cell 1 and the second unit cell 11 from the external environment. The insulating material may be, for example, a resin material. More specifically, the resin material may be, for example, polyethylene terephthalate or polyethylene.

[0034] The outer container 4 has, for example, a multi-layer structure. The outer container 4 may have, for example, a three-layer structure. Specifically, the outer container 4 may have, for example, a first insulating layer, a moisture-proof layer, and a second insulating layer. In this case, the moisture-proof layer is located, for example, between the first insulating layer and the second insulating layer. Specifically, the moisture-proof layer may be covered, for example, by the first insulating layer and the second insulating layer. Furthermore, the moisture-proof layer may be in direct contact with, for example, the first insulating layer and the second insulating layer.

[0035] The first insulating layer includes, for example, a resin material. Specifically, the resin material may be, for example, polyethylene terephthalate or polyethylene naphthalate. The moisture-proof layer is a member provided to prevent oxygen and water that have permeated the first resin layer from reaching the second resin layer. The moisture-proof layer includes, for example, a metal material. Specifically, the metal material may be, for example, aluminum or copper. The second resin layer includes, for example, a resin material. Specifically, the resin material may be, for example, polyethylene or polypropylene.

[0036] The outer container 4 has a moisture-proof layer, which protects the first unit cell 1 and the second unit cell 11 from oxygen and water that have permeated the first resin layer. This reduces the possibility of deterioration of the first unit cell 1 and the second unit cell 11. As a result, the possibility of damage to the electrochemical cell 50 can be reduced.

[0037] When the outer container 4 has a rectangular shape when viewed in the stacking direction of the first unit cell 1 and the second unit cell 11, the dimensions may be, for example, 50 mm to 600 mm in length, 50 mm to 400 mm in width, and 1 mm to 50 mm in thickness.

[0038] Conventionally, such single cells can have uneven thickness due to manufacturing errors. Furthermore, the expansion and contraction of the positive and negative electrodes and the generation of gas caused by repeated charge and discharge reactions in the electrochemical cell module can also cause uneven thickness. As a result, uniform pressure cannot be applied to each single cell, which can lead to increased interfacial resistance between the power-generating elements. Increased interfacial resistance prevents uniform charge and discharge reactions within each single cell, accelerating the deterioration of each single cell.

[0039] The liquid layer 14 is provided to transmit external pressure to the first unit cell 1 and the second unit cell 11. The liquid layer 14 is located at least between the first unit cell 1 and the second unit cell 11. The liquid layer 14 is in direct contact with the first unit cell 1 and the second unit cell 11. More specifically, the liquid layer 14 is located on the surface between the first packaging body 3 of the first unit cell 1 and the second packaging body 13 of the opposing second unit cell 11. The liquid layer 14 may be filled, for example, between the first packaging body 3 of the first unit cell 1 and the second packaging body 13 of the opposing second unit cell 11. This allows the liquid layer 14 to be located inside the recess even if recesses exist on the surfaces of the first unit cell 1 and the second unit cell 11, which have uneven thicknesses. Therefore, even if recesses exist, pressure can be applied uniformly to the main surfaces of the first unit cell 1 and the second unit cell 11 via the liquid layer 14. Here, the main surfaces of the first unit cell 1 and the second unit cell 11 refer to surfaces that extend across the stacking direction when the first unit cell 1 and the second unit cell 11 are stacked in the electrochemical cell 50. The main surfaces of the first unit cell 1 and the second unit cell 11 may include the surface of the first packaging body 3 of the first unit cell 1 and the surface of the second packaging body 13 of the second unit cell 11, which face each other with the liquid layer 14 interposed therebetween. This allows charge / discharge reactions to occur without uneven interfacial resistance within the first unit cell 1 and the second unit cell 11, reducing the possibility of deterioration of the first unit cell 1 and the second unit cell 11. As a result, the life of the electrochemical cell 50 can be improved.

[0040] Here, the liquid layer 14 refers to a layer of liquid substance located between the first packaging body 3 and the second packaging body 13 and in direct contact with the first packaging body 3 and the second packaging body 13.

[0041] The liquid layer 14 may also contain, for example, an organic solvent. More specifically, the organic solvent may be ethylene carbonate, γ-butyrolactone, or the like. The liquid layer 14 may also contain a low-molecular-weight polymer material having fluidity. More specifically, the polymer material having fluidity may be, for example, polyethylene oxide. The liquid layer 14 may also be a silicon-based polymer material. The silicon-based polymer material may be, for example, silicone.

[0042] Furthermore, a water-absorbing material can be used for the liquid layer 14. This allows the water-absorbing material to absorb moisture that has infiltrated into the outer container 4 from the outside, making it difficult for moisture to infiltrate into the first unit cell 1 and the second unit cell 11. This can improve the life of the electrochemical cell 50. As the water-absorbing material, for example, a water-absorbing polymer can be used. As the water-absorbing polymer, for example, polyacrylonitrile can be used.

[0043] Furthermore, the liquid layer 14 may contain an inorganic material. As shown in FIG. 3, the inorganic material may be dispersed in a liquid substance as filler 17 and contained in the liquid layer 14. The inorganic material may be, for example, porous filler 17. Zeolite, for example, can be used as the porous filler 17. This allows the zeolite to absorb moisture that has entered the outer container 4, thereby improving the life of the electrochemical cell 50. The proportion of the inorganic material in the liquid layer 14 may be, for example, 0.1% to 10% by mass.

[0044] The inorganic material may include, for example, a metal filler 17. The metal filler 17 may be, for example, a material that reacts with water or oxygen. More specifically, iron, copper, aluminum, or the like may be used as the metal filler 17. This allows water and oxygen that have entered the outer container 4 to react with the metal filler 17, making it difficult for them to enter the first unit cell 1 and the second unit cell 11. This can improve the life of the electrochemical cell 50. The thickness of the liquid layer 14 may be, for example, 1 μm to 100 μm.

[0045] For example, when stacking the first unit cell 1 and the second unit cell 11, the liquid layer 14 may be provided on one of the first packaging body 3 of the first unit cell 1 and the second packaging body 13 of the second unit cell 11, and the other packaging body may be stacked on top of that. Alternatively, the liquid layer 14 may be provided between the first unit cell 1 and the second unit cell 11 when, for example, the first unit cell 1 and the second unit cell 11 are placed in the outer container 4 of the electrochemical cell 50 and the outer container 4 is sealed.

[0046] 4 shows a cross-sectional view corresponding to FIG. 2 of another example of an electrochemical cell module. When viewed from the stacking direction of the first unit cell 1 and the second unit cell 11, the liquid layer 14 may be located, for example, in the region where the first power generating element 2 and the second power generating element 12 overlap. This makes it easier to apply pressure uniformly to the first power generating element 2 and the second power generating element 12. This reduces the possibility of deterioration of the electrochemical cell 50.

[0047] Furthermore, the liquid layer 14 may be made of a material with higher thermal conductivity than the electrolyte used in the first power generating element 2 and the second power generating element 12. This makes it easier for heat generated in the first unit cell 1 and the second unit cell 11 to be transferred to the liquid layer 14. This makes it less likely for heat to be trapped in the first unit cell 1 and the second unit cell 11. As a result, the life of the electrochemical cell 50 can be improved.

[0048] FIG. 5 shows a cross-sectional view corresponding to FIG. 2 of yet another example of an electrochemical cell module. For example, as shown in FIG. 5, the liquid layer 14 may be located between at least one of the first packaging body 3 and the second packaging body 13 and the outer container 4. In the example shown in FIG. 5, a liquid layer 14 is located between the first packaging body 3 and the second packaging body 13, and another liquid layer 14 is located between the first packaging body 3 and the outer container 4 on the opposite side of the first power generating element 2. Furthermore, a liquid layer 14 is located between the first packaging body 3 and the second packaging body 13, and another liquid layer 14 is located between the second packaging body 13 and the outer container 4 on the opposite side of the second power generating element 12. This makes it possible to prevent the first unit cell 1 and the second unit cell 11 from shifting positions within the outer container 4. This makes it possible to prevent damage to the joints between the first and second terminals and the external terminals. As a result, the possibility of damage to the electrochemical cell 50 can be reduced.

[0049] Furthermore, the liquid layer 14 may be made of a material with a higher viscosity than the electrolyte used in the first power generating element 2 and the second power generating element 12. This can further reduce the possibility of the first unit cell 1 and the second unit cell 11 being misaligned within the outer container 4. As a result, the possibility of the electrochemical cell 50 being damaged can further be reduced.

[0050] FIG. 6 shows a cross-sectional view corresponding to FIG. 2 of yet another example of an electrochemical cell module. As shown in FIG. 6, when viewed in the stacking direction of the first unit cell 1 and the second unit cell 11, the liquid layer 14 may have, for example, a first liquid layer 14a located in the region where the first power generating element 2 and the second power generating element 12 overlap, and a second liquid layer 14b located in the region where the first power generating element 2 and the second power generating element 12 do not overlap. In this case, the thickness of the second liquid layer 14b may be greater than the thickness of the first liquid layer 14a. The thicknesses of the first liquid layer 14a and the second liquid layer 14b are dimensions in the stacking direction of the first unit cell 1 and the second unit cell 11. This makes it difficult for external forces acting in a direction perpendicular to the stacking direction of the first unit cell 1 and the second unit cell 11 to be transmitted to the first unit cell 1 and the second unit cell 11. This reduces the possibility of damage to the electrochemical cell 50.

[0051] Here, the thicknesses of first liquid layer 14a and second liquid layer 14b may be measured, for example, as follows: Electrochemical cell 50 is cooled to a low temperature equal to or lower than the freezing points of first liquid layer 14a and second liquid layer 14b, causing first liquid layer 14a and second liquid layer 14b to solidify, and then electrochemical cell 50 is cut in a direction perpendicular to the main surface and the cross section is observed for measurement. Alternatively, the thicknesses of first liquid layer 14a and second liquid layer 14b may be measured, for example, by ultrasonic measurement.

[0052] Next, another embodiment of the present disclosure will be described. FIG. 7 shows a cross-sectional view corresponding to FIG. 2 of another example of an electrochemical cell module. In this embodiment, as shown in FIG. 7, instead of the aforementioned liquid layer 14, an electrolyte solution 18 is located between the first packaging body 3 and the second packaging body 13. This allows uniform pressure to be applied to the first unit cell 1 and the second unit cell 11, similar to the liquid layer 14, thereby reducing the possibility of deterioration of the electrochemical cell 50. The electrolyte solution 18 is also located inside the first packaging body 3 and the second packaging body 13. The electrolyte solution 18 located between the first packaging body 3 and the second packaging body 13 may be the same as the electrolyte solution contained in the first power generating element 2 and the second power generating element 12.

[0053] FIG. 8 shows a cross-sectional view corresponding to FIG. 2 of yet another example of an electrochemical cell module. As shown in FIG. 8, at least one of the first packaging body 3 and the second packaging body 13 may have an opening 15. The opening 15 may be formed, for example, by cutting a slit in at least one of the first packaging body 3 and the second packaging body 13. The opening 15 may be formed, for example, by cutting a rectangular portion of at least one of the first packaging body 3 and the second packaging body 13. The dimensions of the opening 15 may be, for example, 10 mm to 200 mm in length and 10 mm to 50 mm in width. As charge and discharge reactions are repeated in the first unit cell 1 or the second unit cell 11, the electrolyte in the first unit cell 1 or the second unit cell 11 may decrease. In such a case, the electrolyte 18 located between the first packaging body 3 and the second packaging body 13 can enter the inside of the first packaging body 3 or the second packaging body 13 through the opening 15. Therefore, the electrolyte in the first unit cell 1 or the second unit cell 11 is less likely to run out, and the life of the electrochemical cell 50 can be improved.

[0054] Furthermore, the opening 15 may be located, for example, in a region where the first packaging body 3 and the first power generating element 2 do not overlap or where the second packaging body 13 and the second power generating element 12 do not overlap when viewed from a direction perpendicular to the stacking direction of the first unit cell 1 and the second unit cell 11. This makes it easier for the electrolyte solution 18 located between the first packaging body 3 and the second packaging body 13 to enter the inside of the first unit cell 1 or the second unit cell 11, thereby improving the life of the electrochemical cell 50.

[0055] The housing 5 is a member having a space for accommodating the electrochemical cell 50 therein. The housing 5 is a member for protecting the electrochemical cell 50 from the external environment. More specifically, the housing 5 is a member for protecting the electrochemical cell 50 from external forces received from the external environment. The housing 5 is, for example, box-shaped. The housing 5 may be formed, for example, by forming one member into a rectangular parallelepiped shape. Alternatively, the housing 5 may be formed, for example, by combining two or more members.

[0056] The housing 5 includes, for example, a metal material. This increases the rigidity of the housing 5, making it difficult for external forces from the external environment to be transmitted to the electrochemical cell 50. The housing 5 can protect the electrochemical cell 50 from the external environment. Examples of metal materials that can be used include aluminum and stainless steel. This makes it easier for heat generated in the electrochemical cell 50 to be transmitted to the housing 5, improving heat dissipation efficiency. As a result, the life of the electrochemical cell 50 can be improved.

[0057] The housing 5 may have, for example, a plurality of members. The housing 5 may have, for example, two main panels 7, two side panels 8, a bottom panel 9, and a terminal cover 6. Specifically, the housing 5 may be made of a combination of a metal material and a resin material.

[0058] The terminal cover 6 is provided to protect the external connection terminals of the electrochemical cell 50. Therefore, the terminal cover 6 faces the external connection terminal side of the electrochemical cell 50. The terminal cover 6 may be, for example, rectangular when viewed from the external connection terminal side of the electrochemical cell 50. The terminal cover 6 may be made of, for example, a resin material. Specifically, the resin material may be polyethylene terephthalate or polyethylene naphthalate. The dimensions of the bottom surface of the terminal cover 6, when viewed in a direction perpendicular to the terminal side surface of the electrochemical cell 50, may be, for example, 200 mm to 600 mm in length, 50 mm to 300 mm in width, and 0.1 mm to 5 mm in thickness. Furthermore, the dimensions of the side surface of the terminal cover 6, when rectangular, may be, for example, 200 mm to 600 mm in length, 50 mm to 300 mm in width, and 0.1 mm to 5 mm in thickness.

[0059] The main face plate 7 is provided to protect the main surface of the electrochemical cell 50. Therefore, the main face plate 7 faces the main surface of the electrochemical cell 50. Here, the main surface of the electrochemical cell 50 refers to the surface of the outer container 4 that extends in a direction intersecting the stacking direction when the first unit cell 1 and the second unit cell 11 are stacked inside the electrochemical cell 50. The main face plate 7 may have a rectangular shape when viewed in a direction perpendicular to the main surface of the electrochemical cell 50. For example, a metal material can be used for the main face plate 7. Specific examples of the metal material include aluminum and stainless steel. This allows heat generated in the electrochemical cell 50 to be easily transferred to the outside. As a result, the life of the electrochemical cell 50 can be improved.

[0060] Furthermore, the main face plate 7 may be made of, for example, a resin material. As the resin material, for example, a heat-resistant resin material with a high melting point can be used. As the heat-resistant resin material, for example, polyethylene terephthalate (PET) can be used. This can electrically insulate the electrochemical cell 50 from the external environment, thereby reducing the possibility of a short circuit between the electrochemical cell 50 and the external environment. When the main face plate 7 has a rectangular shape when viewed from a direction perpendicular to the side surface of the electrochemical cell 50, the dimensions of the main face plate 7 may be, for example, 200 mm to 600 mm in length, 50 mm to 300 mm in width, and 0.5 mm to 5 mm in thickness.

[0061] The side plate 8 is provided to protect the side surface of the electrochemical cell 50. Therefore, the side plate 8 faces the side surface of the electrochemical cell 50. The side plate 8 may be in contact with the electrochemical cell 50, for example. The side plate 8 may be rectangular when viewed from a direction perpendicular to the side surface of the electrochemical cell 50. The side plate 8 may be made of, for example, a metal material. Specifically, the side plate 8 may be made of, for example, aluminum or stainless steel. This makes it easier for heat generated in the electrochemical cell 50 to be transferred to the outside. As a result, the life of the electrochemical cell 50 can be improved.

[0062] The side panel 8 may be made of, for example, a resin material. The resin material may be, for example, a heat-resistant resin material. The heat-resistant resin material may be, for example, PET. This electrically insulates the electrochemical cell 50 from the external environment, thereby reducing the possibility of a short circuit between the electrochemical cell 50 and the external environment. The dimensions of the side panel 8, when rectangular when viewed from a direction perpendicular to the side surface of the electrochemical cell 50, may be, for example, 200 mm to 600 mm in length, 50 mm to 300 mm in width, and 0.5 mm to 5 mm in thickness.

[0063] The bottom plate 9 is provided to protect the surface of the electrochemical cell 50 opposite to the surface on which the external connection terminals are provided. Therefore, the bottom plate 9 may be in contact with the surface of the electrochemical cell 50 opposite to the surface on which the external connection terminals are provided. The bottom plate 9 may be rectangular when viewed in a direction perpendicular to the surface on which the external connection terminals are provided. The bottom plate 9 may also be made of, for example, a metal material. Examples of the metal material that may be used include aluminum and stainless steel. This allows heat generated from the electrochemical cell 50 to be easily transferred to the outside. As a result, the life of the battery can be improved.

[0064] The bottom plate 9 may be made of, for example, a resin material. Examples of the resin material include a heat-resistant resin material. Examples of the heat-resistant resin material include PET. This electrically insulates the electrochemical cell 50 from the external environment, thereby reducing the possibility of a short circuit between the electrochemical cell 50 and the external environment. The bottom plate 9 may be formed by bending a portion of the side plate 8 or the main plate 7. The dimensions of the bottom plate 9 may be, for example, 200 mm to 600 mm in length, 50 mm to 300 mm in width, and 0.5 mm to 5 mm in thickness, if the bottom plate 9 has a rectangular shape when viewed perpendicularly to the surface opposite to the surface on which the external connection terminals of the electrochemical cell 50 are provided.

[0065] In each of the above examples, the electrochemical cell module 100 may include, for example, a mechanism for applying pressure to the main surfaces of the first unit cells 1 and the second unit cells 11 via the outer container 4 within the housing 5. Such a pressure mechanism includes, for example, a pressure plate 10 and an elastic member. The first unit cells 1 and the second unit cells 11 may be held in the housing 5 under pressure by the pressure plate 10 and the elastic member. The pressure plate 10 may be configured to be displaceable between the main panel 7 and the electrochemical cells 50 within the housing 5 in order to apply pressure to the electrochemical cells 50.

[0066] The pressure plate 10 can be made of, for example, a metal material. Examples of metal materials that can be used include aluminum and stainless steel. This allows heat generated from the electrochemical cell 50 to be easily transferred to the outside. As a result, the life of the electrochemical cell 50 can be improved.

[0067] Furthermore, the pressure plate 10 may be made of, for example, a resin material. Examples of the resin material that can be used include thermosetting resins. Examples of the thermosetting resin that can be used include epoxy resins, phenolic resins, and melamine resins. This allows the electrochemical cell 50 to be electrically insulated from the external environment, thereby reducing the possibility of a short circuit between the electrochemical cell 50 and the external environment.

[0068] The pressure plate 10 can be made of, for example, a resin material and a metal material. For example, a resin material can be used for the portion of the pressure plate 10 that comes into contact with the electrochemical cell 50. This can electrically insulate the electrochemical cell 50 from the pressure plate 10. As a result, the possibility of a short circuit between the electrochemical cell 50 and the external environment can be reduced. Furthermore, using a metal material can make the pressure plate 10 less susceptible to damage.

[0069] The elastic body is located between the pressure plate 10 and the main panel 7 of the housing 5. The elastic body is provided to apply pressure to the pressure plate 10 and thereby to apply pressure to the electrochemical cell 50. The elastic body can be, for example, a spring 16. The spring 16 can be, for example, a spiral-shaped coil spring. The spring 16 can also be, for example, a curved leaf spring. The spring 16 can be, for example, a metal material. Examples of the metal material that can be used include steel and stainless steel. For example, in the case of a spiral shape, the dimensions of the spring 16 can be a diameter of 5 mm to 50 mm, a length of 10 mm to 50 mm, and a pitch of 1 mm to 10 mm.

[0070] The elastic body may be made of a rubber material. The rubber material may be, for example, in a plate shape. The rubber material may be, for example, in the same shape as the pressing plate 10. The rubber material may include, for example, natural rubber. The rubber material may also include, for example, synthetic rubber.

[0071] Alternatively, the first cell 1 and the second cell 11 may not be provided with a pressure mechanism, and the main surfaces of the first cell 1 and the second cell 11 may be pressed by the casing 5 via the outer container 4. FIG. 9 shows a cross-sectional view of yet another example of an electrochemical cell module, corresponding to FIG. 2. As shown in FIG. 9, for example, the main face plate 7 of the casing 5 may press the outer container 4, thereby pressurizing the main surfaces of the first cell 1 and the second cell 11 via the outer container 4. The casing 5 may have the main face plate 7 pressurizing the main surfaces of the first cell 1 and the second cell 11, for example, by screwing the main face plate 7 and the side panel 8 together.

[0072] For ease of explanation, in Figures 1 to 9, each unit cell, each power generating element, each packaging body, and each terminal are illustrated as having the same shape and aligned outer peripheries, but in the strict sense, they do not have to have the same shape and aligned outer peripheries. For example, there may be a deviation in the outer periphery due to manufacturing tolerances. Furthermore, the electrochemical cell 50 in the casing 5 is not limited to a single electrochemical cell 50, and for example, two or more electrochemical cells 50 may be stacked in the casing 5.

[0073] The present disclosure can be implemented in various other forms without departing from its spirit or main features. Therefore, the above-described embodiments are merely examples in all respects, and the scope of the present disclosure is defined by the claims and is not limited by the text of the specification. Furthermore, all modifications and variations within the scope of the claims are within the scope of the present invention.

[0074] The electrochemical cell according to the present disclosure can be implemented in the following configurations (1) to (5).

[0075] (1) a first unit cell having a first power generating element and a first packaging body having the first power generating element therein; a second unit cell including a second power generating element and a second packaging body having the second power generating element therein; an outer container having the first unit cell and the second unit cell therein; a liquid layer located between the first package and the second package and in direct contact with the first package and the second package.

[0076] (2) The electrochemical cell according to the above configuration (1), wherein the liquid layer is located between at least one of the first packaging body and the second packaging body and the outer container.

[0077] (3) The first unit cell and the second unit cell are stacked in one direction, and when the first unit cell and the second unit cell are viewed from the one direction, the liquid layer has a first liquid layer located in a region where the first power generating element and the second power generating element overlap, and a second liquid layer located in a region where the first power generating element and the second power generating element do not overlap, The electrochemical cell according to the above configuration (1) or (2), wherein the second liquid layer is thicker than the first liquid layer.

[0078] (4) a first unit cell having a first power generating element and a first packaging body having the first power generating element therein; a second unit cell including a second power generating element and a second packaging body having the second power generating element therein; an outer container having the first unit cell and the second unit cell therein; An electrochemical cell, characterized in that an electrolyte is located inside the first packaging body, inside the second packaging body, and between the first packaging body and the second packaging body.

[0079] (5) The electrochemical cell according to the above configuration (4), wherein at least one of the first packaging body and the second packaging body has an opening.

[0080] The electrochemical cell module according to the present disclosure can be implemented in the following configurations (6) and (7).

[0081] (6) The electrochemical cell according to any one of the above configurations (1) to (5), a housing having the electrochemical cell therein; a mechanism for pressurizing the first unit cell and the second unit cell.

[0082] (7) The electrochemical cell according to any one of the above configurations (1) to (5), a housing having the electrochemical cell therein; The housing is an electrochemical cell module that pressurizes the first unit cell and the second unit cell. [Explanation of symbols]

[0083] 1. First unit cell 2. First power generating element 3 First package 4 Outer container 5. Cabinet 6 Terminal cover 7 Main plate 8 Side plate 9 Bottom plate 10 Pressure plate 11 Second unit cell 12 Second power generating element 13 Second package 14 Liquid layer 14a 1st liquid layer 14b 2nd liquid layer 15 Opening 16 springs 17 Filler 18 Electrolyte 50 electrochemical cells 100 electrochemical cell modules

Claims

1. a first unit cell including a first power generating element and a first packaging body having the first power generating element therein; a second unit cell including a second power generating element and a second packaging body having the second power generating element therein; an outer container having the first unit cell and the second unit cell therein; an electrolyte is located inside the first packaging body, inside the second packaging body, and between the first packaging body and the second packaging body; the first unit cell and the second unit cell are stacked in the outer container, the first packaging body has openings on both sides in a first direction perpendicular to a stacking direction of the first unit cell and the second unit cell, The electrochemical cell, wherein the second packaging body has openings on both sides in the first direction.

2. the openings on both sides of the first package do not overlap in the stacking direction, The electrochemical cell according to claim 1 , wherein the openings on both sides of the second package do not overlap in the stacking direction.

3. a first unit cell including a first power generating element and a first packaging body having the first power generating element therein; a second unit cell including a second power generating element and a second packaging body having the second power generating element therein; an outer container having the first unit cell and the second unit cell therein; an electrolyte is located inside the first packaging body, inside the second packaging body, and between the first packaging body and the second packaging body; the first unit cell and the second unit cell are stacked in the outer container, At least one of the first packaging body and the second packaging body has an opening, an opening located in a region where the first packaging body and the first power-generating element do not overlap or where the second packaging body and the second power-generating element do not overlap when viewed from a direction perpendicular to a stacking direction of the first unit cell and the second unit cell.

4. 4. The electrochemical cell according to claim 1, wherein the opening is provided in a portion of one end of the first packaging body and / or the second packaging body.

5. The electrochemical cell according to any one of claims 1 to 4, a housing having the electrochemical cell therein; a mechanism for pressurizing the first unit cell and the second unit cell.

6. The electrochemical cell according to any one of claims 1 to 4, a housing having the electrochemical cell therein; The housing is an electrochemical cell module that pressurizes the first unit cell and the second unit cell.

Images