JP2019153533A - Secondary battery recycling method and system - Google Patents

Abstract

To provide a secondary battery recycling method and system, in which work safety in discharge treatment of a secondary battery is enhanced.SOLUTION: A secondary battery recycling method includes: a replacement step S1 in which a plurality of secondary batteries 1 housed in a bottomed container 91 whose upper surface is opened in an opening 95 so that a plus terminal 12 faces upward are transferred to a bottomed container 21 for discharge, whose upper surface is opened in a second opening 25 so that the plus terminal 12 faces upward; and a heating step S2 in which the secondary batteries 1 housed in the container 21 for discharge are discharged by being heated at a temperature of 100°C or more and 250°C or less for a predetermined time.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a secondary battery recycling method and a recycling system.

  Conventionally, when disassembling and recycling a used secondary battery, the secondary battery is discharged in advance in order to ensure the safety of the dismantling work (see, for example, Patent Document 1).

  In Patent Document 1, in a lithium ion secondary battery using an organic electrolyte and a nickel metal hydride secondary battery using an aqueous electrolyte, the battery function of the secondary battery is destroyed by heating at 150 ° C. or higher. It is described that the voltage can be made zero, and the safety in the subsequent dismantling work is improved.

JP 2013-187142 A

  By the way, when applying the technique of Patent Document 1 to a large amount of secondary batteries, for example, a large amount of secondary batteries before the discharge treatment must be safely set in the heat treatment layer. Such a setting method is not specifically disclosed, and there is room for improvement.

  Therefore, an object of the present invention is to provide a recycling method and a recycling system for a secondary battery with improved work safety in the discharge treatment of the secondary battery.

  In order to solve the above-described problem, the secondary battery recycling method according to the first technology disclosed herein is such that the plus terminal faces upward in a bottomed container whose upper surface is opened at the first opening. A replacement step of transferring a plurality of stored secondary batteries to a bottomed discharge container whose upper surface is opened at the second opening so that the positive terminal faces upward, and the discharge battery is stored in the discharge container A heating step of discharging the secondary battery by heating at a temperature of 100 ° C. or higher and 250 ° C. or lower for a predetermined time, and the replacement step includes the first opening with respect to the container in which the secondary battery is accommodated. A first covering step in which a bottomed reversing container whose bottom surface is opened at the third opening so as to cover the side is covered from the third opening, and the container, the secondary battery, and the reversing container 1st inversion to invert the set A first pulling step of pulling out the container from the set of the reversed container, the secondary battery and the reversing container to house the secondary battery in the reversing container; and pulling out the container A second covering step of inserting the discharge container into the gap between the generated reversal container and the secondary battery from the second opening side; the reversal container; the secondary battery; and the discharge container. A second reversing step for reversing the set, and the rechargeable battery stored in the discharge container by pulling out the reversal container from the reversed reversing container, the secondary battery, and the discharge container set. And a second drawing step for obtaining the above.

  Secondary batteries used for recycling such as used are usually delivered in a state where a plurality of secondary batteries are placed in one plastic case or the like with their positive terminals aligned upward. Then, in order to use the secondary battery for the heating process, considering that the electrolyte solution evaporates from the safety valve provided around the plus terminal in the heating process, for example, a plurality of the plus terminals remain upward in a heat resistant container or the like. Rechargeable batteries must be transferred. However, it is difficult from the viewpoint of safety to transfer the secondary battery before discharge to a heat-resistant container, for example, manually. According to the present technology, by reversing the secondary battery twice using the reversing container, the container at the time of arrival can be safely and easily replaced with the discharging container. Then, the plurality of secondary batteries before discharge can be safely and easily accommodated in the discharge container with their positive terminals facing upward without directly touching them. Thus, the safety of the heating process in the recycling process of the secondary battery can be enhanced.

  A second technique is characterized in that, in the first technique, a plurality of holes are formed in at least one of a side surface and a bottom surface of the discharge vessel.

  According to the present technology, the plurality of holes are formed in at least one of the side surface and the bottom surface of the discharge container, so that the temperature increase rate of the secondary battery in the heating process can be improved. Thus, discharge of the secondary battery can be promoted.

  A third technique is characterized in that, in the first or second technique, the bottom surface of the reversing container is formed of an insulating member.

  In the set of the container, the secondary battery, and the reversing container that are reversed in the first reversing step, the plus terminal of the secondary battery can abut on the bottom of the reversing container. According to the present technology, by using the bottom portion of the reversing container as an insulating member, it is possible to improve the safety of work in the replacement process.

  A fourth technique is the electrode according to any one of the first to third techniques, wherein the secondary battery includes the positive terminal at an upper portion, and a positive electrode material, a negative electrode material, and a separator are wound therein. A wound type secondary battery containing a group structure, cutting out the secondary battery after the heating step from the discharge container, and cutting off the top and bottom of the secondary battery; A cutting step of obtaining a secondary battery body in which the electrode group structure is accommodated, an extrusion step of extruding and extracting the electrode group structure from the secondary battery body, the positive electrode material of the electrode group structure, and the negative electrode A material collecting step for separating at least one of a material, a separation step for separating the separator, a work for peeling and collecting the positive electrode material from the positive electrode material, and a work for peeling and collecting the negative electrode material from the negative electrode material; Having And features.

  According to the present technology, the secondary battery discharged in the heating process is subjected to a dismantling operation and the positive electrode material and / or the negative electrode material is collected, thereby improving the safety of the secondary battery recycling operation.

  According to a fifth technique, in the fourth technique, the cleaning step of cleaning the positive terminal and the negative terminal of the secondary battery after the removal step and before the cutting step, and the cleaned second step A voltage measuring step for measuring a voltage of the secondary battery, and a removing step for removing the secondary battery whose residual voltage exceeds a predetermined value in the voltage measuring step are provided.

  According to the present technology, it is possible to further improve the safety of the dismantling work after the cutting process by removing the secondary battery that has been insufficiently discharged from the secondary battery after the heating process.

  A recycling system for a secondary battery according to a sixth technology disclosed herein includes a plurality of secondary batteries accommodated in a bottomed container whose upper surface is opened at the first opening so that the plus terminal faces upward. And a replacement means for transferring the positive terminal to the bottomed discharge container whose upper surface is opened at the second opening so that the positive terminal faces upward, and the secondary battery accommodated in the discharge container is 100 ° C. or more and 250 ° C. Heating means for discharging by heating at a temperature below for a predetermined time, and the replacement means has a lower surface that covers the first opening side of the container in which the secondary battery is accommodated. First covering means for covering the bottomed reversing container opened at the three openings from the third opening side; first reversing means for reversing the set of the container, the secondary battery and the reversing container; , Inverted A first pulling means for pulling out the container from the set of the secondary battery and the reversing container, and the discharge container in the gap between the reversing container and the secondary battery generated by pulling out the container. Second covering means inserted from the second opening side, second reversing means for reversing the set of the reversing container, the secondary battery and the discharging container, the reversed reversing container, and the secondary And a second pulling means for pulling out the reversing container from the battery and the discharge container set.

  According to the present technology, by reversing the secondary battery twice using the reversing container, the container at the time of arrival can be safely and easily replaced with the discharging container. Then, the plurality of secondary batteries before discharge can be safely and easily accommodated in the discharge container with their positive terminals facing upward without directly touching them. Thus, the safety of discharge work by heating the secondary battery can be enhanced.

  A seventh technique is characterized in that, in the sixth technique, a plurality of holes are formed in at least one of a side surface and a bottom surface of the discharge vessel.

  According to the present technology, since the plurality of holes are formed in at least one of the side surface and the bottom surface of the discharge container, the temperature increase rate of the secondary battery during heating by the heating unit can be improved. Thus, discharge of the secondary battery can be promoted.

  According to an eighth technology, in the sixth or seventh technology, the secondary battery includes the positive terminal at an upper portion, and an electrode group structure in which a positive electrode material, a negative electrode material, and a separator are wound inside. A wound-type secondary battery housed therein, taking out the secondary battery discharged by the heating means from the discharge container, cutting means for cutting off the top and bottom of the secondary battery, An extruding means for extruding and taking out the electrode group structure from the secondary battery from which the upper part and the bottom part have been cut off; and a separating means for separating the positive electrode material, the negative electrode material, and the separator of the electrode group structure; And a material recovery means for performing at least one of a work of peeling and collecting the positive electrode material from the positive electrode material and a work of peeling and collecting the negative electrode material from the negative electrode material.

  According to the present technology, the secondary battery discharged by the heating means is disassembled and the positive electrode material and / or the negative electrode material is collected, thereby realizing a highly safe secondary battery recycling operation.

  As described above, according to the present invention, by reversing the secondary battery twice using the reversing container, the container at the time of arrival can be safely and easily replaced with the discharging container. Then, the plurality of secondary batteries before discharge can be safely and easily accommodated in the discharge container with their positive terminals facing upward without directly touching them. Thus, the safety of the heating process in the recycling process of the secondary battery can be enhanced.

3 is a flowchart for explaining a secondary battery recycling method according to the first embodiment. It is a flowchart for demonstrating an example of the discharge process of FIG. It is a flowchart for demonstrating an example of the dismantling process of FIG. 1 is a diagram schematically showing a secondary battery recycling system according to Embodiment 1. FIG. It is a top view which shows the container which accommodated the secondary battery of recycling object. It is sectional drawing in the VV line of FIG. 5A. It is a flowchart for demonstrating an example of the replacement | exchange process of FIG. It is a figure for demonstrating the 1st coating process of FIG. It is a figure for demonstrating the 1st inversion process of FIG. It is a figure for demonstrating the 1st extraction process of FIG. It is a figure for demonstrating the 2nd coating process of FIG. It is a figure for demonstrating the 2nd inversion process of FIG. It is a figure for demonstrating the 2nd extraction process of FIG. It is a bottom view of the container for discharge. It is a top view of the container for discharge. It is a side view of the container for discharge. It is sectional drawing in the VIII-VIII line of FIG. 8B. It is a top view of the container for inversion. It is a bottom view of the container for inversion. It is sectional drawing in the IX-IX line of FIG. 9A.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The following description of the preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its application, or its application.

<Secondary battery recycling method and system>
As shown in FIG. 1, the secondary battery recycling method according to Embodiment 1 includes a discharge step SI and a disassembly step SII. As shown in FIG. 2, for example, the discharge process SI includes a replacement process S1 and a heating process S2. For example, as shown in FIG. 3, the dismantling step SII includes an extraction step S3, a cleaning step S4, a voltage measurement step S5, a removal step S6, a cutting step S7, an extrusion step S8, a separation step S9, and a material. And a recovery step S10.

  FIG. 4 shows an example of the secondary battery recycling system 100 according to the first embodiment. The recycling system 100 includes a discharge device portion 100a that performs the discharge step SI and a disassembly device portion 100b that performs the disassembly step SII. The discharge device unit 100a and the dismantling device unit 100b are configured to perform the operations of the respective steps of FIGS. 2 and 3 on the secondary battery 1, respectively.

  Hereinafter, each structure of the recycle system 100 and the recycle method performed using the recycle system 100 will be described in detail.

<Secondary battery>
As shown in FIG. 4, FIG. 5A and FIG. 5B, the secondary battery 1 to be recycled in this embodiment is a cylinder for mounting mobile devices such as mobile phones, smartphones, tablets, notebook computers, digital cameras, and wearable devices. This is a type of wound lithium ion secondary battery. The secondary battery 1 includes a battery main body 11 (secondary battery main body), a positive terminal 12 formed at the top as an external extraction electrode, and a negative terminal 13 formed at the bottom as an external extraction electrode. . Note that a safety valve (not shown) for suppressing an excessive increase in the pressure inside the battery body 11 is formed on the upper portion where the plus terminal 12 is formed. The battery body 11 includes a cylindrical can-made battery outer case 11a, an electrode group structure 14 accommodated in the battery outer case 11a, an electrolytic solution, and the like. The electrode group structure 14 is a structure formed by winding a positive electrode material 15, a negative electrode material 17, and separators 16 and 18.

The lithium ion secondary battery is not particularly limited. Specifically, for example, a cobalt-based lithium ion battery using lithium cobaltate (LiCoO ₂ ) as a positive electrode material and graphite (LiC ₆ ) as a negative electrode material, Nickel lithium ion battery using lithium nickelate (LiNiO ₂ ) as a positive electrode material, manganese lithium ion battery using lithium manganate (LiMn ₂ O ₄ ) as a positive electrode material, lithium iron phosphate (LiFePO ₄ ) as positive electrode Iron phosphate lithium-ion battery used as a material, ternary lithium-ion battery using three types of raw materials of cobalt, nickel, and manganese in which a part of cobalt of lithium cobaltate, which is a positive electrode material, is replaced with nickel and manganese , lithium titanate as a negative electrode material _{(Li 4} Ti _{5 O 12} A titanate-based such as a lithium ion battery using lithium manganate and the like as a positive electrode material.

The lithium ion battery includes an electrolytic solution containing an electrolyte and an organic solvent. The electrolytic solution may have a configuration included in a general lithium ion battery. Examples of electrolytes include, but are not limited to, LiPF ₆ , LiCF ₃ SO ₃ , LiC ₄ F ₉ SO ₃ , LiClO ₄ , LiBF ₄ , LiAsF ₆ , LiN (CF ₃ SO ₂ ) ₂ , LiC (CF ₃ And various lithium salts such as SO ₂ ) ₃ and mixtures thereof. Examples of organic solvents include, but are not limited to, specific examples such as ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, γ-butyrolactone, 1,2-dimethoxyethane, 1,2- Examples include diethoxyethane, tetrahydrofuran, 1,3-dioxolane, and mixed solvents thereof.

<Container>
As shown in FIGS. 5A and 5B, the secondary batteries 1 to be recycled are received in a container 91 in a state where a plurality of the positive batteries 12 are accommodated so that the plus terminals 12 face upward.

  The container 91 is a bottomed container whose upper surface is opened at the first opening 95. The material of the container 91 is not particularly limited, and examples thereof include plastic and vinyl chloride resin.

<Discharge process>
≪Replacement process≫
In order to use the secondary battery 1 for the heating step S2, the positive terminal 12 faces upward in a heat-resistant container, for example, considering that the electrolytic solution evaporates from the safety valve provided around the positive terminal 12 in the heating step S2. It is desirable to transfer a plurality of secondary batteries 1 as they are.

  That is, the replacement step S1 is a step of transferring the plurality of secondary batteries 1 accommodated in the container 91 to the discharge container 21 so that the plus terminal 12 faces upward, as indicated by the white arrow B1 in FIG. It is.

  For example, as shown in FIG. 6, the replacement step S1 includes a first covering step S11, a first inversion step S12, a first drawing step S13, a second covering step S14, a second inversion step S15, A drawing step S16.

  7A to 7F illustrate each step of the replacement step S1. Although details will be described later, the replacement step S1 includes a first holder 41 (first inversion means, first extraction means), a second holder 42 (first covering means, first inversion means, second inversion means, second extraction). Means) and a replacement device 40 (replacement means) provided with a third holder 43 (second covering means, second reversing means), using the reversing container 51. The replacement device 40 further includes a motor (not shown) such as a servo motor and a control device (not shown) that controls driving of the motor, the first holder 41, the second holder 42, and the third holder 43.

-Discharge vessel-
As shown in FIGS. 8A to 8D, the discharge container 21 is a bottomed container whose upper surface is opened at the second opening 25, and includes a discharge container bottom surface 22 (bottom surface) and a discharge container side surface 24 (side surface). ). The discharge vessel 21 needs to be made of a material having heat resistance and chemical resistance in order to be used in the heating step S2. Examples of such a material include stainless steel, aluminum, titanium, and iron. Made of metal.

A plurality of bottom surface holes 22 a (holes) are formed on the bottom surface 22 of the discharge container 21. Further, a plurality of side surface holes 24 a (holes) are formed on the discharge container side surface 24 of the discharge container 21. The bottom surface hole 22a and the side surface hole 24a promote the contact of the hot air in the dryer 61 (heating means) to the secondary battery 1 in the heating step S2, and improve the temperature increase rate of the secondary battery 1, From the viewpoint of shortening the discharge treatment time by promoting the evaporation of the electrolyte in the secondary battery 1, for example, the hole diameter is 5 mm or more and 30 mm or less, and the number of formation per unit area (100 cm ² ) is 5 or more and 400 or less. It can be a hole. In addition, although the structure provided with at least one of the bottom face hole part 22a and the side surface hole part 24a may be sufficient, from a viewpoint of shortening discharge processing time, both the bottom face hole part 22a and the side surface hole part 24a are formed. It is desirable that

  Further, the shapes of the bottom surface hole portion 22a and the side surface hole portion 24a are not particularly limited, and may be circular as shown in FIGS. 8A to 8D, or may be elliptical, square, rectangular, polygonal, or the like. Good. Moreover, the formation method of the bottom surface hole part 22a and the side surface hole part 24a is not specifically limited, A punching mesh as shown to FIG. 8A-FIG. 8D may be sufficient, and net shape may be sufficient. In addition, when the shapes of the bottom hole portion 22a and the side hole portion 24a are other than circular, the hole diameter can be the maximum width. Specifically, for example, when the shape of the bottom hole 22a and the side hole 24a is rectangular, the hole diameter can be the length of the diagonal line as the maximum width.

-Reversing container-
As shown in FIGS. 9A to 9C, the reversing container 51 is a bottomed container whose bottom surface is opened at the third opening 55, and the reversing container bottom 52 (the bottom surface of the reversing container) and the reversing container A container side wall part 54 and a reversing container step part 53 are provided. The reversing container step portion 53 is for suppressing the fall of the secondary battery 1 in the replacement step S1 and improving work safety.

  The reversing container 51 is an insulating member from the viewpoint of improving safety in the replacement step S1 because the positive terminal 12 of the secondary battery 1 can be contacted in the first reversing step S12 to the second covering step S14. Is desirable. In particular, the inversion container bottom 52 is preferably formed of an insulating member. The insulating member may be a member made of a fluororesin such as acrylic resin, vinyl chloride resin, synthetic rubber, or Teflon (registered trademark). Note that only the inner surface of the reversing container bottom 52 where the positive terminal 12 of the secondary battery 1 abuts may be an insulating member.

  The reversing container 51 is configured such that the reversing container bottom 52 and the reversing container side wall 54 are prepared as separate members and assembled in the state shown in FIG. It may be a member. Moreover, although it is preferable to provide the inversion container level | step-difference part 53 from a viewpoint of improving the safety | security of the operation | work in replacement | exchange process S1, it is good also as a structure which does not provide. In addition, as a configuration for suppressing the overturning of the secondary battery 1, a configuration other than the reversing container step portion 53 can be appropriately employed.

-First coating step-
As shown in FIG. 7A, the first covering step S11 is a step of covering the container 91 in which the secondary battery 1 is accommodated with the reversing container 51.

  Specifically, the container 91 in which the secondary battery 1 is accommodated is held by the first holder 41. The reversing container 51 held by the second holder 42 is placed on the container 91 so as to cover the first opening 95 side of the container 91 from the third opening 55 side. Thus, the set of the container 91, the secondary battery 1, and the reversing container 51 is sandwiched between the first holder 41 and the second holder 42 with the reversing container step 53 being in contact with the upper end of the container 91. Is done.

  In addition, in the configuration in which “the reversing container 51 is covered from the third opening 55 side so as to cover the first opening 95 side of the container 91”, for example, as described above, “the reversing container bottom portion” 52 and a member that becomes the container side wall portion 54 for reversal are prepared as separate members and assembled on the upper side of the container 91 in a state as shown in FIG. 7A.

-1st inversion process-
The first inversion step S12 is a step of inverting the set of the container 91, the secondary battery 1, and the inversion container 51.

  As shown in FIG. 7B, in this step, the first holder 41 and the second holder 42 are driven by a motor and a control device (not shown), and their positions are switched. Thus, the set of the container 91, the secondary battery 1 and the reversing container 51 sandwiched between the first holder 41 and the second holder 42 is reversed as the first holder 41 and the second holder 42 move. . At this time, the secondary battery 1 housed in the container 91 is in a state in which the positive terminal 12 is in contact with the inner surface of the reversing container bottom 52.

-First drawing process-
Then, as shown in FIG. 7C, the first holder 41 pulls out the container 91 from the set of the inverted container 91, the secondary battery 1, and the reversing container 51 in the first extraction step S13. Thereby, the secondary battery 1 is accommodated in the reversing container 51 in a state where the plus terminal 12 is in contact with the reversing container bottom 52. After the container 91 is pulled out, a gap 56 is formed between the reversing container 51 and the secondary battery 1.

-Second coating step-
The second covering step S <b> 14 is a step of inserting the discharge container 21 into the gap 56.

  Specifically, the discharge container 21 held by the third holder 43 is inserted into the gap 56 from the second opening 25 side as shown in FIG. 7D. Then, the upper end of the discharge vessel 21 is in contact with the inversion vessel step 53. Thus, the set of the reversing container 51, the secondary battery 1, and the discharging container 21 is sandwiched between the second holder 42 and the third holder 43.

-Second reversal process-
The second reversing step S15 is a step of inverting the set of the reversing container 51, the secondary battery 1, and the discharging container 21.

  Specifically, as shown in FIG. 7E, in this step, the second holder 42 and the third holder 43 are driven by a motor and a control device (not shown) and are positioned relative to each other, as in the first reversing step S12. Will be replaced. Then, the set of the reversing container 51, the secondary battery 1 and the discharging container 21 sandwiched between the second holder 42 and the third holder 43 is reversed as the second holder 42 and the third holder 43 move. Is done. At this time, the secondary battery 1 housed in the reversing container 51 is in a state in which the negative terminal 13 of the secondary battery 1 is in contact with the discharge container bottom surface 22 of the discharge container 21.

-Second drawing process-
As shown in FIG. 7F, in the second extraction step S <b> 16, the second holder 42 extracts the reversing container 51 from the reversed reversing container 51, secondary battery 1, and discharge container 21 set. Thus, the secondary battery 1 accommodated in the discharge vessel 21 with the positive terminal 12 facing upward is obtained.

≪Heating process≫
The heating step S2 is a step of introducing the secondary battery 1 accommodated in the discharge vessel 21 into the dryer 61 and heating it at a predetermined temperature for a predetermined time.

  Specifically, as indicated by an arrow B <b> 2 in FIG. 4, the secondary battery 1 is introduced into the dryer 61 while being accommodated in the discharge vessel 21. The introduction of the secondary battery 1 into the dryer 61 may be performed manually, or the discharge container 21 containing the secondary battery 1 is introduced into the dryer 61 using a forklift or a conveyor device. Alternatively, an automatic configuration may be used.

  As the dryer 61, a commercially available circulating constant temperature dryer, a fully exhausted oven, or the like can be used. However, since the flammable organic solvent is discharged out of the secondary battery 1 by evaporation of the electrolyte, the explosion-proof drying is performed. From the viewpoint that it is desirable to use a vessel, it is desirable to use an all exhaust type oven or the like. The dryer 61 is preferably provided with a cleaning device, a scrubber, and the like for cleaning the exhaust gas containing the organic solvent of the electrolytic solution. Moreover, the safety | security in heating process S2 can be improved by replacing the inside of dryer 61 with inert gas, such as nitrogen gas, for example.

  The predetermined temperature is preferably 100 ° C. or higher and 250 ° C. or lower, more preferably 120 ° C. or higher and 220 ° C. or lower, and particularly preferably 150 ° C. or higher and 200 ° C. or lower from the viewpoint of promoting evaporation of the electrolytic solution. The predetermined time is preferably 30 minutes or longer and 3 hours or shorter, more preferably 40 minutes or longer and 2 hours or shorter from the viewpoint of promoting sufficient evaporation of the electrolytic solution.

  The voltage of the secondary battery 1 before the heating step S2 is, for example, more than 0.5V, particularly 2.5V or more. The residual voltage of the secondary battery 1 discharged in the heating step S2 is preferably 0.5 V or less, more preferably 0.4 V or less, particularly preferably from the viewpoint of improving the safety of work after the next step. 0.2V or less. Further, the percentage of the number of secondary batteries 1 whose residual voltage is 0.5 V or less after the heating step S2 with respect to the total number of secondary batteries 1 accommodated in one discharge vessel 21 is expressed as a percentage. Is the discharge rate (%), the discharge rate is preferably 50% or more, more preferably from the viewpoint of ensuring the safety of the subsequent disassembly step SII and efficiently performing the recycling process of the secondary battery 1. Is 69% or more, particularly preferably 79% or more.

  After the heating is completed, the secondary battery 1 stored in the discharge vessel 21 is taken out from the dryer 61 or from the dryer 61, for example, until the temperature of the secondary battery 1 is about 60 ° C. or less. It is preferable to do.

<Dismantling process>
≪Removal process≫
The extraction step S3 is a step of taking out the cooled secondary battery 1 from the discharge vessel 21 by an unillustrated extraction means after the heating step S2. The take-out means is not particularly limited, but may be manual or may be constituted by an industrial robot arm or the like. As shown by an arrow B3 in FIG. 4, the secondary battery 1 taken out from the discharge vessel 21 is arranged on the belt conveyor 62a and sent out in the direction indicated by the arrow A1.

≪Cleaning process≫
The fed secondary battery 1 is cleaned by brushing the portions of the positive terminal 12 and the negative terminal 13 by the brush member 63 in the cleaning step S4. The cleaning method of the secondary battery 1 is not limited to brushing, and may be a wiping, solvent cleaning, air blow, or a combination of these methods.

≪Voltage measurement process≫
In the voltage measurement step S5, the residual voltage of the washed secondary battery 1 is measured by the voltage measuring device 64. A control unit (not shown) is connected to the voltage measuring device 64, and it is determined whether or not the residual voltage is equal to or less than a predetermined value such as 0.5V.

≪Removal process≫
The removal step S6 is a step of removing the determined secondary battery 1 when it is determined in the voltage measurement step S5 that the residual voltage has exceeded a predetermined value.

  More specifically, first, an operating door 65 is disposed at the tip of the belt conveyor 62a. The operating door 65 is connected with an actuator (not shown) as a driving means and a control unit (not shown) for controlling driving. In the voltage measurement step S5, when it is determined that the residual voltage exceeds the predetermined value, the operation door 65 is opened as shown by the arrow A3 and arranged at the position indicated by the alternate long and short dash line by the action of the control unit and the actuator. The Then, as shown by arrows A4 and A6, the secondary battery 1b whose residual voltage exceeds a predetermined value is guided to the opened operating door 65 and sent to the auxiliary belt conveyor 62c. On the other hand, the secondary battery 1a whose residual voltage is determined to be equal to or less than the predetermined value is guided to the closed operating door 65 and sent to the main belt conveyor 62b as indicated by arrows A2 and A5.

  The secondary battery 1a sent to the main belt conveyor 62b is sent to the next cutting step S7. On the other hand, the secondary battery 1b sent to the auxiliary belt conveyor 62c can be returned to the heating step S2 again.

  Note that the removal step S6 is not limited to the configuration in FIG. 4, and other configurations such as a configuration in which the secondary battery 1 b in which the residual voltage is determined to exceed a predetermined value are removed using, for example, an industrial robot arm or the like. It is good.

≪Cutting process≫
And the secondary battery 1a is provided to cutting process S7, as shown by arrow B4 of FIG. The cutting step S7 is a step of cutting off the upper part where the plus terminal 12 of the secondary battery 1a is arranged and the bottom part where the minus terminal 13 is arranged. Thus, the battery body 11 in which the electrode group structure 14 is accommodated is obtained. The recycle system 100 is provided with a cutting machine (cutting means) (not shown), and the upper and bottom parts of the secondary battery 1a are cut off by the cutting machine. The cutting machine is not particularly limited, and a commercially available machine such as a cutting machine equipped with a diamond cutter can be used as appropriate.

≪Extrusion process≫
Next, the secondary battery 1a is subjected to an extrusion step S8 as indicated by an arrow B5 in FIG. The extruding step S8 is a step of extruding the electrode assembly 14 from the battery body 11. The recycling system 100 is provided with an extrusion rod 67 (extrusion means), and the extrusion rod 67 is inserted into the battery body 11 from either the top side or the bottom side of the battery body 11 after the cutting step S7. Then, the internal electrode group structure 14 is pushed out. Thus, the electrode group structure 14 is taken out.

≪Separation process≫
And the electrode group structure 14 taken out by extrusion process S8 is provided to isolation | separation process S9, as shown by arrow B6 of FIG. The separation step S9 is a step of separating the positive electrode material 15, the negative electrode material 17, and the separators 16 and 18 of the electrode group structure 14.

  The recycling system 100 is provided with a separation device 68 (separation means), and the separation device 68 separates the positive electrode material 15, the negative electrode material 17, and the separators 16 and 18. Specifically, the separation device 68 is provided with a roller 68a on which the electrode group structure 14 is set. As the roller 68a rotates, as shown by an arrow A9, the positive electrode materials 15 bonded to each other, The negative electrode material 17 and the separators 16 and 18 are unwound and sent out. The fed positive electrode material 15, negative electrode material 17, and separators 16 and 18 are separated from each other and wound around rollers 68b, 68c, 68d, and 68e.

≪Material recovery process≫
The separation device 68 is provided with a peeling blade 69 (material recovery means), and the positive electrode material 15a is peeled off from the positive electrode material 15 wound around the roller 68b. Thus, the positive electrode material 15a is recovered by the recovery unit 70 in the material recovery step S10. The positive electrode current collector 15b of the positive electrode material 15 is wound around the roller 68b.

  The method of peeling the positive electrode material 15a from the positive electrode material 15 is not limited to the method of physically scraping off the positive electrode material 15a with the above-described peeling blade 69, but by chemically treating the positive electrode material 15 with it. Other methods such as a method of collecting the positive electrode material 15a may be adopted.

  4 shows only the configuration for recovering the positive electrode material 15a from the positive electrode material 15, the negative electrode material is recovered from the negative electrode material 17 in addition to or instead of the configuration for recovering the positive electrode material 15a. You may provide the structure to do.

  Furthermore, it is good also as a structure which performs separation process S9 and material collection | recovery process S10 with another apparatus.

<Effect>
The secondary battery recycling method and the recycling system 100 according to the present embodiment have the following effects.

  That is, it is difficult from the viewpoint of safety to transfer the secondary battery 1 before discharge to, for example, the discharge container 21 manually. In the above-described replacement step S1, by reversing the secondary battery 1 twice using the reversing container 51, the container 91 at the time of arrival can be safely and easily replaced with the discharging container 21. Then, the plurality of secondary batteries 1 before discharge can be safely and easily accommodated in the discharge container 21 with their positive terminals facing upward, for example, without an operator directly touching them. Thus, the safety of the next heating step S2 can be improved.

  In addition, as a method for discharging the secondary battery 1, generally, salt water treatment, freezing treatment, firing treatment, and the like can be mentioned. For example, in salt water treatment, problems such as prolonged discharge time and generation of bad odor after treatment, The treatment has a problem of high cost, and the baking treatment has a problem of high cost and oxidation of the battery material after the treatment. In the above-described heating step S2, the secondary battery 1 is heated in the above temperature range to evaporate the electrolytic solution. Therefore, the secondary battery 1 is effectively discharged at low cost without causing problems such as odor generation and oxidation. Can be made.

  Furthermore, in the heating step S2 of the present embodiment, as described above, the positive terminal 12 of the secondary battery 1 is directed upward using the discharge vessel 21 having the side surface hole 24a and / or the bottom surface hole 22a. The secondary battery 1 is held. Thereby, evaporation of the electrolyte solution in the secondary battery 1 can be promoted, the discharge time can be shortened, and the discharge efficiency of the secondary battery 1 can be improved.

  Then, by disassembling the secondary battery 1 discharged in the heating step S2 in the next disassembly step SII, the positive electrode material and / or the negative electrode material can be recovered safely and efficiently. The safety and efficiency of the battery 1 recycling work can be improved.

  In the dismantling process SII, the cleaning process S4, the voltage measurement process S5, and the removal process S6 are provided after the extraction process S3 and before the cutting process S7, so that in the dismantling work after the cutting process S7. It is possible to reduce the influence of the residual voltage on the device, workers, etc., and further improve the safety of the dismantling work.

(Other embodiments)
Hereinafter, other embodiments according to the present invention will be described in detail. In the description of these embodiments, the same parts as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the first embodiment, the secondary battery 1 is a cylindrical wound lithium ion battery mounted on a mobile device, but is not limited to this configuration. Specifically, the secondary battery 1 is, for example, for mounting an electronic device other than a mobile device, for a vehicle, for an electric bicycle, for an electric tool, for a drone, for an industrial robot, for an electricity storage system, etc. Also good. The secondary battery 1 may be, for example, a lithium ion polymer battery, a nickel hydride secondary battery, or the like. Further, the secondary battery 1 may be a battery cell as a single battery such as the lithium ion battery of the first embodiment, and is not limited to this configuration, and a plurality of such battery cells (for example, six) Or about 8) a battery module connected in series as one component unit, an assembled battery configured by connecting a plurality of the battery modules in series, and the charged state of the assembled battery and the battery module. Electronic devices such as control devices and relays for disconnecting electrical circuits, safety plugs for mechanically disconnecting circuits and cooling blowers for cooling assembled batteries, signal lines and power lines connecting each component, The battery pack etc. which consist of the case etc. which airtightly store these may be sufficient.

  The plurality of secondary batteries are not limited to those including a plurality of the above-described battery cells, but also include those including any of the above-described battery modules, assembled batteries, and battery packs. In addition, a combination of two or more of the above-described battery cells, battery modules, assembled batteries, and battery packs is also included.

  The electrode structure of the secondary battery 1 is not limited to the wound type, and may be, for example, a stacked type. Moreover, the exterior container of the secondary battery 1 is not restricted to a can, For example, a laminate film exterior etc. may be sufficient. Furthermore, the form of the secondary battery 1 is not limited to the cylindrical type, and may be a square type, a sheet type, or the like. In the case of a shape other than the cylindrical shape, the plus terminal 12, the minus terminal 13, and the safety valve can be formed on the upper portion or the like. The portion where the plus terminal 12, the minus terminal 13, and the safety valve are formed can be accommodated and received in the container 91 in an upward state. Then, in replacement | exchange process S1, it can accommodate in the discharge container 21 so that the part in which the plus terminal 12, the minus terminal 13, and the safety valve were formed may be in an upward state.

  Further, the replacement device 40 is not limited to the configuration of the first embodiment, and any configuration can be adopted as long as each configuration shown in FIG. 6 can be performed. Specifically, in the first embodiment, the first holder 41 and the third holder 43 are different members, but may be the same member. Moreover, it is good also as a structure which performs 1st coating process S11-1st extraction process S13 with one apparatus, and performs 2nd coating process S14-2nd extraction process S16 with another apparatus.

  Furthermore, in the said Embodiment 1, although it was the structure provided with washing | cleaning process S4, voltage measurement process S5, and removal process S6 after extraction process S3 and before cutting process S7, these processes Is an optional step. For example, when the influence of the residual voltage can be reduced by grounding each device of the recycling system 100, the cleaning step S4, the voltage measurement step S5, the removal step S6, It is good also as a structure which does not provide. Thereby, dismantling process SII can be simplified more.

  In the first embodiment, the extrusion step S8 is configured to use the extrusion rod 67. However, the configuration is not limited to the configuration described above. For example, the electrode group structure 14 is taken out by other extrusion means such as manual work. Also good.

  Next, specific examples will be described.

<Heating experiment>
Example 1
As a secondary battery, 48 cylindrical wound nickel-type lithium ion batteries (voltage 3.6 V) with a maximum diameter of 18.5 mm and a maximum length of 65 mm were used for discharge made of stainless steel with the positive terminal facing upward. It accommodated in the container and it heated using the constant temperature dryer (As-One Corporation OF-450S).

As the discharge container, a stainless steel container having a width of 15 cm, a depth of 18 cm, and a height of 10 cm, and a punching mesh having a hole diameter of 8 mm on both the side surface and the bottom surface was used. The number of holes formed was 20 per 100 cm ^{2 on} both the side surface and the bottom surface.

  The heating conditions were a temperature of 190 ° C. and a time of 1.5 hours. Specifically, the oven is heated to 190 ° C. in advance, the discharge container containing the battery is introduced into the oven, the oven is opened 1.5 hours after the discharge container is taken out, and then left to cool at room temperature in the atmosphere for 3 hours. did.

  Thereafter, the battery was taken out from the discharge container, the plus terminal and the minus terminal were wiped with a waste cloth, and the residual voltage was measured with a commercially available tester (manufactured by MonotaRO Co., Ltd.).

(Example 2)
The experiment was performed in the same manner as in Example 1 except that the hole diameter of the punching mesh of the discharge vessel was 10 mm.

(Example 3)
The experiment was performed in the same manner as in Example 1 except that the hole diameter of the punching mesh of the discharge vessel was 12 mm.

Example 4
The secondary batteries were 56 cylindrical wound ternary lithium ion batteries having a maximum diameter of 14 mm and a maximum length of 65 mm (voltage 3.6 V). Moreover, the size of the discharge container was 12 cm wide × 14 cm deep × 10 cm high. Further, the heating condition was 190 ° C. for 2 hours. The experiment was performed in the same manner as in Example 2 except for these configurations.

(Example 5)
The experiment was performed in the same manner as in Example 4 except that the hole diameter of the punching mesh of the discharge vessel was 12 mm.

<About the heating experiment results>
The results of the heating experiments of Examples 1 to 6 are shown in Table 1.

表１に示すように、実施例１〜３では、いずれにおいても、５０％以上の電池において、残留電圧が０．５Ｖ以下となるまで放電できることが判った。特に、孔径１０ｍｍの実施例２では、全ての電池において、残留電圧が０．５Ｖ以下となり、効率的に放電できることが判った。また、実施例５，６では、全ての電池において残留電圧が０．５Ｖ以下となるまで放電できることが判った。

As shown in Table 1, in each of Examples 1 to 3, it was found that 50% or more of the batteries can be discharged until the residual voltage becomes 0.5 V or less. In particular, in Example 2 having a hole diameter of 10 mm, it was found that in all the batteries, the residual voltage was 0.5 V or less and the battery could be discharged efficiently. In Examples 5 and 6, it was found that discharging can be performed until the residual voltage becomes 0.5 V or less in all the batteries.

  INDUSTRIAL APPLICABILITY The present invention is extremely useful because it can provide a secondary battery recycling method and a recycling system with improved work safety in secondary battery discharge treatment.

1 Secondary battery 11 Battery body (secondary battery body)
11a Battery outer casing 12 Positive terminal 13 Negative terminal 14 Electrode group structure 15 Positive electrode material 15a Positive electrode material 16, 18 Separator 17 Negative electrode material 21 Discharge container 22 Discharge container bottom surface (bottom surface)
22a Bottom hole (hole)
24 Discharge vessel side (side)
24a Side hole (hole)
25 2nd opening part 40 replacement apparatus (exchange means)
41 1st holder (1st inversion means, 1st extraction means)
42 2nd holder (1st coating | coated means, 1st inversion means, 2nd inversion means, 2nd extraction means)
43 Third holder (second covering means, second reversing means)
51 Reversing container 52 Reversing container bottom (bottom of reversing container)
55 3rd opening 56 Crevice 61 Dryer (heating means)
67 Extrusion rod (extrusion means)
68 Separation device (separation means)
69 Peeling blade (material recovery means)
91 Container 95 1st opening part 100 Recycling system S1 Replacement process S10 Material recovery process S11 1st coating process S12 1st inversion process S13 1st drawing process S14 2nd coating process S15 2nd inversion process S16 2nd drawing process S2 Heating process S3 Extraction step S4 Cleaning step S5 Voltage measurement step S6 Removal step S7 Cutting step S8 Extrusion step S9 Separation step

Claims (8)

A plurality of secondary batteries housed in a bottomed container whose upper surface is opened in the first opening so that the positive terminal faces upward, and a bottomed discharge container whose upper surface is opened in the second opening. A replacement process for transferring the positive terminal to face upward;
A heating step of discharging the secondary battery housed in the discharge vessel by heating at a temperature of 100 ° C. or more and 250 ° C. or less for a predetermined time,
The replacement process includes:
A bottomed reversing container whose bottom surface is opened at the third opening is covered from the third opening side so that the container holding the secondary battery covers the first opening side. 1 coating process;
A first reversing step of reversing the set of the container, the secondary battery and the reversing container;
A first pulling step of pulling out the container from the set of the reversed container, the secondary battery and the reversing container and accommodating the secondary battery in the reversing container;
A second covering step of inserting the discharge container into the gap between the reversing container and the secondary battery generated by pulling out the container from the second opening side;
A second reversing step of reversing the set of the reversing container, the secondary battery and the discharging container;
A second extraction step of extracting the reversing container from the inverted reversing container, the secondary battery, and the discharge container set to obtain the secondary battery accommodated in the discharging container. Recycling method of secondary battery characterized by this. In claim 1,
A method for recycling a secondary battery, wherein a plurality of holes are formed in at least one of a side surface and a bottom surface of the discharge vessel. In claim 1 or claim 2,
A method of recycling a secondary battery, wherein the bottom surface of the reversing container is formed of an insulating member. In any one of Claims 1-3,
The secondary battery is a wound type secondary battery that includes the positive terminal at the top and that houses therein an electrode group structure formed by winding a positive electrode material, a negative electrode material, and a separator.
An extraction step of taking out the secondary battery after the heating step from the discharge vessel;
Cutting off the top and bottom of the secondary battery to obtain a secondary battery body in which the electrode group structure is housed; and
An extrusion step of extruding and extracting the electrode group structure from the secondary battery body;
A separation step of separating the positive electrode material, the negative electrode material, and the separator of the electrode group structure;
What is claimed is: 1. A secondary battery comprising: a material recovery step of performing at least one of an operation of peeling and collecting a positive electrode material from the positive electrode material and an operation of peeling and collecting the negative electrode material from the negative electrode material Recycling method. In claim 4,
After the removal step and before the cutting step,
A cleaning step of cleaning the positive terminal and the negative terminal of the secondary battery;
A voltage measuring step of measuring the voltage of the washed secondary battery;
A method for recycling a secondary battery, comprising: a step of removing the secondary battery having a residual voltage exceeding a predetermined value in the voltage measuring step. A plurality of secondary batteries housed in a bottomed container whose upper surface is opened in the first opening so that the positive terminal faces upward, and a bottomed discharge container whose upper surface is opened in the second opening. Replacement means for transferring the positive terminal to face upward;
Heating means for discharging the secondary battery accommodated in the discharge vessel by heating at a temperature of 100 ° C. or higher and 250 ° C. or lower for a predetermined time;
The replacement means includes
A bottomed reversing container whose bottom surface is opened at the third opening is covered from the third opening side so that the container holding the secondary battery covers the first opening side. 1 covering means;
First reversing means for reversing the set of the container, the secondary battery and the reversing container;
A first pulling means for pulling out the container from the inverted container, the secondary battery, and the reversing container set;
Second covering means for inserting the discharge container into the gap between the reversing container and the secondary battery generated by pulling out the container from the second opening side;
A second reversing means for reversing the set of the reversing container, the secondary battery and the discharging container;
A secondary battery recycling system comprising: a second pulling means for pulling out the reversing container from the reversed container, the secondary battery, and the discharge container set. In claim 6,
A recycling system for a secondary battery, wherein a plurality of holes are formed in at least one of a side surface and a bottom surface of the discharge vessel. In claim 6 or claim 7,
The secondary battery is a wound type secondary battery that includes the positive terminal at the top and that houses therein an electrode group structure formed by winding a positive electrode material, a negative electrode material, and a separator.
Taking-out means for taking out the secondary battery discharged by the heating means from the discharge container;
Cutting means for cutting off the top and bottom of the secondary battery;
An extruding means for extruding and taking out the electrode group structure from the secondary battery from which the upper part and the bottom part are cut off;
Separation means for separating the positive electrode material, the negative electrode material, and the separator of the electrode group structure;
Recycling of a secondary battery comprising: material recovery means for performing at least one of an operation of peeling and collecting the positive electrode material from the positive electrode material and an operation of peeling and collecting the negative electrode material from the negative electrode material system.

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