X-ray analysis system

Abstract

To provide an X-ray analysis system that allows for proper observation of electrode conditions. [Solution] The X-ray analysis system obtains analysis data by irradiating a battery cell, which comprises a battery and a laminate housing the battery, with X-rays. The X-ray analysis system comprises a sample holder capable of restraining the battery cell, a holding device that holds the sample holder and can switch the irradiation position which indicates the position where X-rays are irradiated onto the battery cell restrained by the sample holder, and a charging / discharging device that charges and discharges the battery cell restrained by the sample holder, the sample holder having a penetrating portion that can transmit X-rays to multiple points on the battery cell.

Description

Technical Field

[0001] The present invention relates to an X-ray analysis system.

Background Art

[0002] Conventionally, X-ray analysis is known as a method for observing the electrode state of a secondary battery module. The electrode state is, for example, the SOC (State Of Charge) representing the charge state. Different from the method of observing the electrode cross-section by SEM (scanning microscope), X-ray analysis can observe the electrode state of the secondary battery module without processing the secondary battery module for observation. Therefore, it is widely used as a method for observing the electrode state of the secondary battery module (for example, Patent Document 1). The X-ray analysis system described in Patent Document 1 includes a sample switching device that switches the laminate cell (secondary battery module) arranged at the X-ray passing position. In the X-ray analysis system described in Patent Document 1, by switching the laminate cell arranged at the X-ray passing position by the sample switching device, X-ray analysis of a plurality of laminate cells can be efficiently performed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a large secondary battery module, the electrode state of the secondary battery module may vary within the plane of the secondary battery module. However, the X-ray analysis system described in Patent Document 1 observes only the electrode state at a fixed single point within the plane of the secondary battery module. Therefore, in the X-ray analysis system described in Patent Document 1, when variations occur within the plane of the secondary battery module, it may be impossible to appropriately observe the electrode state.

[0005] The present invention aims to provide an X-ray analysis system that can appropriately observe the electrode state in order to solve the above problems. [Means for solving the problem]

[0006] (1) The X-ray analysis system according to the present invention is an X-ray analysis system that obtains analysis data by irradiating a battery cell, which comprises a battery and a laminate housing the battery, with X-rays, and comprises a sample holder capable of restraining the battery cell, a holding device that holds the sample holder and can switch the irradiation position which indicates the position in which the X-rays are irradiated onto the battery cell restrained by the sample holder, and a charging and discharging device that charges and discharges the battery cell restrained by the sample holder, wherein the sample holder has a transmissive portion that can transmit X-rays to multiple points on the battery cell.

[0007] (2) In the X-ray analysis system described in (1) above, the transmission portion may include a plurality of point-shaped partial transmission portions.

[0008] (3) In the X-ray analysis system described in (1) above, the transmission portion may have a wave shape.

[0009] (4) In the X-ray analysis system described in (1) or (2) above, the sample holder comprises a first restraining member to which the X-rays are irradiated and which has a penetrating portion, a second restraining member to which the X-rays that have passed through the first restraining member are irradiated, and a cushioning member disposed between the first restraining member and the battery cell, wherein the sample holder may restrain the battery cell by sandwiching it from both sides with the first restraining member and the second restraining member.

[0010] (5) In the X-ray analysis system described in (4) above, the first restraint member has an X-ray irradiation portion that is irradiated with X-rays from the irradiation direction, the first restraint member has a thick portion and a thin portion that is shorter in length along the irradiation direction than the thick portion, and the transmission portion may be provided in the thin portion.

[0011] (6) In the X-ray analysis system described in (4) above, the second restraint member has an additional transmission portion through which the X-rays that have passed through the transmission portion pass, the transmission portion is a gap formed in the first restraint member, the additional transmission portion is a gap formed in the second restraint member, and the width of the transmission portion may be smaller than the width of the additional transmission portion.

[0012] (7) In the X-ray analysis system described in (4) above, the first restraint member has an X-ray irradiation portion that is irradiated with X-rays from the irradiation direction, and the second restraint member has an additional transmission portion through which the X-rays that have passed through the transmission portion are transmitted, the additional transmission portion is a gap formed in the second restraint member, and the width of the gap formed in the second restraint member may increase as it moves away from the first restraint member when viewed along the irradiation direction.

[0013] (8) In the X-ray analysis system described in (1) or (2) above, the X-ray analysis system further comprises a detection device that detects the X-rays passing through the sample holder and acquires data for X-ray analysis, wherein the holding device switches the irradiation position to a plurality of points, and the charging / discharging device charges and discharges the battery cell at each of the plurality of points in the same pattern from the same charge state, so that the detection device detects the X-rays passing through the sample holder at each of the plurality of points and acquires the electrode state distribution during charging and discharging. [Effects of the Invention]

[0014] According to (1) above, the sample holder has a transmission section. The transmission section can transmit X-rays to multiple points P on the battery cell. Therefore, it is possible to irradiate multiple points in the plane of the battery cell with X-rays and analyze the transmitted X-rays. As a result, even if there is variation from place to place in the plane of the battery cell, the electrode state (e.g., SOC) can be appropriately observed. Therefore, the electrode state distribution in the plane of the battery cell during charging and discharging can be appropriately observed.

[0015] According to (2) above, the permeable portion includes a plurality of point-like partial permeable portions. Therefore, permeable portions can be provided only at the necessary points. For example, if the permeable portion is a hole that is restrained by the first restraining member, the number of holes can be reduced. Therefore, the strength and rigidity of the first restraining member can be improved.

[0016] According to (3) above, the penetrating portion 270 has a wave shape, and therefore, the penetrating portion can transmit X-rays to multiple points on the battery cell over a wide area in the lateral and vertical directions of the battery cell. Therefore, the electrode state can be observed over a wide area in the plane of the battery cell. As a result, the electrode state can be observed appropriately.

[0017] According to (4) above, if the permeable portion is a gap, the force applied to the battery cell may vary within the plane. However, in the sample holder, the cushioning member is placed between the first restraining member and the battery cell. Therefore, the force applied to the battery cell can be equalized.

[0018] According to (5) above, the transparent portion is provided in the thin-walled portion. Therefore, it is possible to improve the strength and rigidity of the first restraining member while suppressing X-ray absorption in the first restraining member.

[0019] According to (6) above, the width of the transmission area is smaller than the width of the additional transmission area. That is, the width of the additional transmission area on the X-ray detection side is larger than the width of the transmission area on the X-ray irradiation side. Therefore, it is possible to obtain an average electrode state in the width direction of the battery cell.

[0020] According to (7) above, when viewed from the first restraining member side, the width of the additional transmission portion increases as it moves away from the first restraining member. Therefore, the width of the additional transmission portion is greater on the X-ray detection side than on the X-ray irradiation side.

[0021] According to (8) above, in the X-ray analysis system, the holding device switches the irradiation position to a plurality of points, and the charge / discharge device charges and discharges the battery cell 600 from the same charge state according to the same pattern for each of the plurality of points. As a result, the detection device detects X-rays transmitted through the sample holder for each of the plurality of points. Therefore, X-ray analysis of the X-rays irradiated and transmitted can be performed at a plurality of points within the plane of the battery cell. As a result, even when there are variations for each location within the plane of the battery cell, the electrode state (e.g., SOC) can be appropriately observed. Therefore, the electrode state distribution within the plane of the battery cell during charge and discharge can be appropriately observed.

Brief Description of the Drawings

[0022] [Figure 1] It is a block diagram of an X-ray analysis system according to an embodiment of the present invention. [Figure 2] It is a schematic exploded perspective view of a sample holder. [Figure 3] It is a schematic front view of the sample holder as viewed from the irradiation direction. [Figure 4] It is a schematic exploded front view of the first restraint member as viewed from the irradiation direction. [Figure 5] It is a schematic exploded front view of the second restraint member as viewed from the irradiation direction. [Figure 6A] It is a schematic cross-sectional view along the XIA-XIA line of FIG. 3. [Figure 6B] It is a schematic cross-sectional view along the XIB-XIB line of FIG. 3. [Figure 7] It is a schematic exploded perspective view of a sample holder. [Figure 8A] It is a schematic front view of the sample holder as viewed from the -Z direction side. [Figure 8B] It is a schematic rear view of the sample holder as viewed from the +Z direction side. [Figure 9] It is a schematic cross-sectional view along the IX-IX line of FIG. 8A. <> [Figure 10] It is a diagram showing an example of the simulation result of the in-plane distribution of the SOC of the battery cell. [Figure 11]This figure shows an example of the X-ray analysis results of the State of Charge (SOC) of a battery cell. [Modes for carrying out the invention]

[0023] [Embodiment 1] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. Referring to Figure 1, an X-ray analysis system 1 according to Embodiment 1 of the present invention will be described. Figure 1 is a block diagram of an X-ray analysis system 1 according to an embodiment of the present invention. In the following description, the X-axis direction of the coordinates shown in Figure 1 may be referred to as the left-right direction (the direction in which the X-axis is positive when viewed from the origin is the right direction), the Z-axis direction may be referred to as the front-back direction (the direction in which the Y-axis is positive when viewed from the origin is the front direction), and the Y-axis direction (the direction perpendicular to the XZ plane) may be referred to as the up-down direction (the direction in which the Y-axis is positive when viewed from the origin is the up direction).

[0024] As shown in Figure 1, the X-ray analysis system 1 comprises an X-ray irradiation device 100, a sample holder 200, a holding device 300, a charging / discharging device 400, and a detection device 500. The X-ray analysis system 1 irradiates a battery cell 600 with X-rays to obtain analysis data. The X-ray analysis system 1 obtains analysis data using, for example, the in-situ XRD (X-ray Diffraction) method or the in-situ XAFS (X-ray Absorption Fine Structure) method.

[0025] The X-ray irradiation device 100 irradiates the sample holder 200 with X-rays X1. In other words, the X-ray irradiation device 100 irradiates the sample holder 200 with X-rays X1 in irradiation direction D1. Irradiation direction D1 is the direction from -Z to +Z.

[0026] The sample holder 200 can restrain the battery cell 600. Details of the sample holder 200 will be described later with reference to Figure 2 and subsequent figures.

[0027] The holding device 300 holds the sample holder 200. The holding device 300 can switch the irradiation position P. The irradiation position P indicates the position where X-rays X1 are irradiated onto the battery cell 600, which is constrained by the sample holder 200. The holding device 300 is, for example, an actuator. The holding device 300 switches the irradiation position P within the plane of the battery cell 600 (in the XY plane) by moving the sample holder 200 in the X-axis direction and the Y-axis direction.

[0028] The charge / discharge device 400 charges and discharges the battery cell 600, which is restrained by the sample holder 200. The charge / discharge device 400 repeatedly charges and discharges the battery cell 600, for example, within a predetermined time. The charge / discharge device 400 continues charging and discharging, for example, when the detection device 500 detects X-rays X2. Alternatively, the charge / discharge device 400 may stop charging and discharging when the detection device 500 detects X-rays X2.

[0029] The detection device 500 detects X-rays X2 passing through the sample holder 200 and acquires data for X-ray analysis. In other words, the detection device 500 detects X-rays X2 passing through the battery cell 600 restrained by the sample holder 200 and acquires data for X-ray analysis.

[0030] In the X-ray analysis system 1, the holding device 300 switches the irradiation position P to multiple points, and the charging / discharging device 400 charges and discharges the battery cell at each of the multiple points P using the same pattern from the same charge state. The detection device 500 then detects the X-rays X2 that pass through the sample holder 200 at each of the multiple points P and obtains the electrode state distribution during charging and discharging. Therefore, the electrode state can be observed appropriately.

[0031] The sample holder 200 will be described with reference to Figures 1 to 5. Figure 2 is a schematic exploded perspective view of the sample holder 200. Figure 3 is a schematic front view of the sample holder 200 as seen from the irradiation direction D1. Figure 4 is a schematic exploded front view of the first restraint member 210 as seen from the irradiation direction D1. Figure 5 is a schematic exploded front view of the second restraint member 260 as seen from the irradiation direction D1.

[0032] As shown in Figure 2, the sample holder 200 includes a first restraining member 210, a cushioning member 220, a first insulating member 230, a second insulating member 250, a second restraining member 260, a permeable portion 270, and an additional permeable portion 280. The first restraining member 210, cushioning member 220, first insulating member 230, second insulating member 250, and second restraining member 260 are arranged in the order of first restraining member 210, cushioning member 220, first insulating member 230, second insulating member 250, and second restraining member 260 from the rear side (-Z direction side). The sample holder 200 restrains the battery cell 600 by sandwiching it from both sides with the first restraining member 210 and the second restraining member 260.

[0033] The battery cell 600 comprises a battery 610 and a laminate 620. The battery 610 is a lithium-ion all-solid-state battery. The battery 610 has a positive electrode terminal 612, a negative electrode terminal 614, and a solid electrolyte (not shown). Note that the battery 610 is not limited to a lithium-ion all-solid-state battery; the electrolyte may be liquid. The laminate 620 houses the battery 610. More specifically, the laminate 620 seals the battery 610.

[0034] The first restraint member 210 is located on one side (-Z direction side) of the battery cell 600. The first restraint member 210 is, for example, plate-shaped. The first restraint member 210 has, for example, a rectangular shape as its main surface. The first restraint member 210 is made of a material that X-rays cannot penetrate. The first restraint member 210 is made of, for example, metal. The first restraint member 210 is irradiated with X-rays X1.

[0035] As shown in Figures 3 and 4, the first restraint member 210 has an upper member 211 and a lower member 212. As shown in Figure 3, the first restraint member 210 has an X-ray irradiated portion 213. The X-ray irradiated portion 213 indicates the part that can be irradiated with X-rays. As shown in Figure 4, the upper member 211 has an upper main body portion 2111, an upper convex portion 2113, and an upper concave portion 2114.

[0036] An upper through-hole 2112 is formed in the upper main body portion 2111. The upper through-hole 2112 is a hole that penetrates the upper main body portion 2111 in the thickness direction (Z-axis direction). A bolt B1 (see Figure 2) is inserted into the upper through-hole 2112. The upper protrusion 2113 is the part that protrudes from the upper main body portion 2111. The upper recess 2114 is the part that is recessed more than the upper protrusion 2113.

[0037] The lower member 212 has a lower main body portion 2121, a lower protrusion 2123, and a lower recess 2124. A lower through hole 2122 is formed in the lower main body portion 2121. The lower through hole 2122 is a hole that penetrates the lower main body portion 2121 in the thickness direction (Z-axis direction). A bolt B1 (see Figure 2) is inserted into the lower through hole 2122. The lower protrusion 2123 is a portion that protrudes from the lower main body portion 2121. The lower recess 2124 is a portion that is recessed compared to the lower protrusion 2123.

[0038] As shown in Figure 3, the upper member 211 and the lower member 212 are positioned with a gap (separation) in the Y-axis direction and facing each other in the Y-axis direction. More specifically, the upper member 211 and the lower member 212 are positioned so that the upper convex portion 2113 and the lower concave portion 2124 face each other in the Y-axis direction. More specifically, the upper member 211 and the lower member 212 are positioned so that the lower convex portion 2123 and the upper concave portion 2114 face each other in the Y-axis direction.

[0039] Refer to Figure 2 again. The cushion member 220 is placed between the first restraining member 210 and the battery cell 600. The cushion member 220 is, for example, plate-shaped. The cushion member 220 has, for example, a rectangular shape as its main surface. The cushion member 220 is formed of, for example, urethane foam.

[0040] The first insulating member 230 is located on one side (-Z direction side) of the battery cell 600. The first insulating member 230 has, for example, a rectangular shape as its main surface. The first insulating member 230 is, for example, rectangular. The first insulating member 230 is made of an insulating material. The first insulating member 230 is made of, for example, resin. The first insulating member 230 is made of a material through which X-rays can pass. The first insulating member 230 can, for example, pass through X-rays X1 irradiated by the X-ray irradiation device 100 (see Figure 1).

[0041] The second insulating member 250 is located on the other side (+Z direction side) of the battery cell 600. The second insulating member 250 is, for example, plate-shaped. The second insulating member 250 has, for example, a rectangular shape as its main surface. The second insulating member 250 is made of an insulating material. The second insulating member 250 is made of, for example, resin. The second insulating member 250 is made of a material through which X-rays can pass. The second insulating member 250 can, for example, pass X-rays that have passed through the battery cell 600.

[0042] The second restraint member 260 is located on the other side (+Z direction side) of the battery cell 600. The second restraint member 260 is, for example, plate-shaped. The second restraint member 260 has, for example, a rectangular shape as its main surface. The second restraint member 260 is made of a material that X-rays cannot penetrate. The second restraint member 260 is made of, for example, metal. The second restraint member 260 is irradiated with X-rays that have passed through the first restraint member 210.

[0043] The second restraining member 260 has an upper member 261 and a lower member 262. As shown in Figure 5, the upper member 261 has an upper main body portion 2611, an upper protrusion 2613, and an upper recess 2614.

[0044] An upper through-hole 2612 is formed in the upper main body portion 2611. The upper through-hole 2612 is a hole that penetrates the upper main body portion 2611 in the thickness direction (Z-axis direction). A bolt B1 (see Figure 2) is inserted into the upper through-hole 2612. The upper protrusion 2613 is the part that protrudes from the upper main body portion 2611. The upper recess 2614 is the part that is recessed more than the upper protrusion 2613.

[0045] The lower member 262 has a lower main body portion 2621, a lower protrusion 2623, and a lower recess 2624. A lower through hole 2622 is formed in the lower main body portion 2621. The lower through hole 2622 is a hole that penetrates the lower main body portion 2621 in the thickness direction (Z-axis direction). A bolt B1 (see Figure 2) is inserted into the lower through hole 2622. The lower protrusion 2623 is a portion that protrudes from the lower main body portion 2621. The lower recess 2624 is a portion that is recessed compared to the lower protrusion 2623.

[0046] The penetrating portion 270 transmits X-rays. More specifically, the penetrating portion 270 transmits, for example, X-rays X1 irradiated from the X-ray irradiation device 100. As shown in Figure 3, in this embodiment, the penetrating portion 270 is provided in the first restraining member 210. In this embodiment, the penetrating portion 270 is a gap formed in the first restraining member 210. Alternatively, the penetrating portion 270 may be provided by blocking the gap formed in the first restraining member 210 with a material that does not easily absorb X-rays. For example, the penetrating portion 270 may be provided by blocking the gap formed in the first restraining member 210 with carbon. In this embodiment, the penetrating portion 270 has a wave shape. The penetrating portion 270 can transmit X-rays to multiple points P of the battery cell 600. Points P1, P2, P3, P4, and P5 are examples of multiple points P. Multiple points P can be set in a region corresponding to the penetrating portion 270. Therefore, the state of the battery cell 600 can be observed at multiple points P. Thus, the electrode state within the plane of the battery cell 600 can be observed. As a result, the electrode state can be properly observed. In addition, in this embodiment, the penetrating portion 270 has a wave shape. Therefore, the penetrating portion 270 can transmit X-rays to multiple points P of the battery cell 600 over a wide range in the horizontal (X-axis direction) and vertical (Y-axis direction) directions of the battery cell 600. Thus, the electrode state can be observed over a wide range within the plane of the battery cell 600. As a result, the electrode state can be properly observed. In this embodiment, the width of the penetrating portion 270 (the width of the gap between the upper member 211 and the lower member 212) is constant. However, the width of the penetrating portion 270 may vary in some parts.

[0047] The additional transmission section 280 transmits X-rays. More specifically, the additional transmission section 280 transmits X-rays that have passed through the transmission section 270, for example. In this embodiment, the additional transmission section 280 is provided in the second restraint member 260. In this embodiment, the additional transmission section 280 is a gap formed in the second restraint member 260. Alternatively, instead of a gap formed in the second restraint member 260, the additional transmission section 280 may be provided by blocking the gap formed in the second restraint member 260 with a material that does not easily absorb X-rays. For example, the additional transmission section 280 may be provided by blocking the gap formed in the second restraint member 260 with carbon. In this embodiment, the additional transmission section 280 has a wave shape. The X-rays X2 that have passed through the additional transmission section 280, that is, the X-rays X2 that have passed through the battery cell 600 and the sample holder 200, reach the detection device 500 (see Figure 1). Therefore, the detection device 500 acquires data for X-ray analysis by detecting X-rays X2. As a result, the electrode state can be observed at multiple points P in the plane of the battery cell 600. Thus, the electrode state can be properly observed. In this embodiment, the additional transmission section 280 has a wave shape. Therefore, the additional transmission section 280 can transmit X-rays from multiple points P of the battery cell 600 toward the detection device 500 over a wide range in the horizontal (X-axis direction) and vertical (Y-axis direction) directions of the battery cell 600. Thus, the electrode state can be observed over a wide range in the plane of the battery cell 600. As a result, the electrode state can be properly observed. In this embodiment, the width of the additional transmission section 280 (the width of the gap between the upper member 261 and the lower member 262) is constant. However, the width of the additional transmission section 280 may vary in some parts.

[0048] The sample holder 200 will be further described with reference to Figures 6A and 6B. Figure 6A is a schematic cross-sectional view along the XIA-XIA line in Figure 3. Figure 6B is a schematic cross-sectional view along the XIB-XIB line in Figure 3.

[0049] As shown in Figures 6A and 6B, the first restraining member 210 has a thick-walled portion 216 and a thin-walled portion 217. The thin-walled portion 217 is thinner than the thick-walled portion 216. The perforated portion 270 is provided in the thin-walled portion 217. The upper through-hole 2112 (see Figure 4) and the lower through-hole 2122 (see Figure 4) are formed in the thick-walled portion 216.

[0050] The second restraining member 260 has a thick portion 266 and a thin portion 267. The thin portion 267 is thinner than the thick portion 266. The additional permeable portion 280 is provided in the thin portion 267. The upper through hole 2612 (see Figure 5) and the lower through hole 2622 (see Figure 5) are formed in the thick portion 216.

[0051] In this embodiment, the width of the transmission section 270 (length along the Y-axis) is the same as the width of the additional transmission section 280 (length along the Y-axis). However, the width of the transmission section 270 may be different from the width of the additional transmission section 280. In this case, it is preferable that the width of the transmission section 270 is smaller than the width of the additional transmission section 280. Since the additional transmission section 280 is positioned at a location corresponding to the transmission section 270, the X-rays X1 irradiated from the X-ray irradiation device 100 pass through the transmission section 270, through the battery cell 600, pass through the additional transmission section 280, and the X-rays X2 reach the detection device 500.

[0052] As described above with reference to Figures 1 to 6, in the X-ray analysis system 1 according to this embodiment, the sample holder 200 has a transmission section 270. The transmission section 270 can transmit X-rays to multiple points P on the battery cell 600. Therefore, X-rays can be irradiated to multiple points P in the plane of the battery cell 600 and the transmitted X-rays can be analyzed. As a result, even if there is variation from place to place in the plane of the battery cell 600, the electrode state (e.g., SOC) can be appropriately observed. Therefore, the electrode state distribution in the plane of the battery cell 600 during charging and discharging can be appropriately observed.

[0053] Furthermore, since the penetrating portion 270 has a wave shape, it is possible for the penetrating portion 270 to transmit X-rays to multiple points P on the battery cell 600 over a wide area in the lateral (X-axis direction) and vertical (Y-axis direction) directions of the battery cell 600. Therefore, the electrode state can be observed over a wide area in the plane of the battery cell 600. As a result, the electrode state can be properly observed.

[0054] Furthermore, if the permeable portion 270 is a gap, the force applied to the battery cell 600 may vary within the plane. However, in the sample holder 200, the cushioning member 220 is positioned between the first restraining member 210 and the battery cell 600. Therefore, the force applied to the battery cell 600 can be equalized.

[0055] Furthermore, the transparent portion 270 is provided in the thin-walled portion 217. Therefore, it is possible to improve the strength and rigidity of the first restraining member 210 while suppressing X-ray absorption in the first restraining member 210.

[0056] Furthermore, in the X-ray analysis system 1, the holding device 300 switches the irradiation position P to multiple points, and the charging / discharging device 400 charges and discharges the battery cell 600 at each of these points using the same charging state and pattern. As a result, the detection device 500 detects the X-rays X2 that pass through the sample holder 200 at each of these points. Therefore, X-rays can be irradiated at multiple points P within the plane of the battery cell 600, and the transmitted X-rays can be analyzed. Consequently, even if there is variation from location to location within the plane of the battery cell 600, the electrode state (e.g., SOC) can be appropriately observed. Therefore, the electrode state distribution within the plane of the battery cell 600 during charging and discharging can be appropriately observed.

[0057] [Embodiment 2] Referring to Figures 7 to 9, the X-ray analysis system 1 according to Embodiment 2 of the present invention will be described. Figure 7 is a schematic exploded perspective view of the sample holder 200 according to Embodiment 2 of the present invention. Figure 8A is a schematic front view of the sample holder 200 viewed from the -Z direction. Figure 8B is a schematic rear view of the sample holder 200 viewed from the +Z direction. Figure 9 is a schematic cross-sectional view along the line IX-IX in Figure 8A. The X-ray analysis system 1 according to Embodiment 2 differs from the X-ray analysis system 1 according to Embodiment 1 in that the transmission section 270 and the additional transmission section 280 are different. The differences between Embodiment 2 and Embodiment 1 will be mainly described below.

[0058] As shown in Figure 7, the sample holder 200 includes a first restraining member 210, a cushioning member 220, a first insulating member 230, a second insulating member 250, a second restraining member 260, a permeable portion 270, and an additional permeable portion 280. In Embodiment 2, the arrangement of the cushioning member 220 and the first insulating member 230 differs from that of Embodiment 1.

[0059] As shown in Figure 8A, the first restraint member 210 has a main body 218. A through hole 2182 is formed in the main body 218. The through hole 2162 is a hole that penetrates the main body 218 in the thickness direction (Z-axis direction). A bolt B1 is inserted into the through hole 2162. The permeable portion 270 is provided on the first restraint member 210. In this embodiment, the permeable portion 270 includes a plurality of partial permeable portions 272. In this embodiment, the permeable portion 270 includes nine partial permeable portions 272. The nine partial permeable portions 272 are spaced apart in the X-axis and Y-axis directions. In this embodiment, the nine partial permeable portions 272 are arranged in a matrix of three in the X-axis direction and three in the Y-axis direction. Each of the plurality of partial permeable portions 272 is point-shaped. The plurality of partial permeable portions 272 are provided on the first restraint member 210. Each of the multiple partially transparent portions 272 is a hole that penetrates the main body portion 218 in the thickness direction (Z-axis direction).

[0060] As shown in Figure 8B, the second restraint member 260 has a main body portion 268. A through hole 2682 is formed in the main body portion 268. The through hole 2682 is a hole that penetrates the main body portion 268 in the thickness direction (Z-axis direction). A bolt B1 is inserted into the through hole 2682. An additional permeable portion 280 is provided on the second restraint member 260. The additional permeable portion 280 includes a plurality of partial additional permeable portions 282. In this embodiment, the additional permeable portion 280 includes nine partial additional permeable portions 282. The nine partial permeable portions 272 are arranged with spacing in the X-axis and Y-axis directions. In this embodiment, the nine partial additional permeable portions 282 are arranged in a matrix of three in the X-axis direction and three in the Y-axis direction. In this embodiment, each of the plurality of partial additional permeable portions 282 is point-shaped. The plurality of partial additional permeable portions 282 are provided on the second restraint member 260. Each of the multiple additional transparent sections 282 is a hole that penetrates the main body 218 in the thickness direction (Z-axis direction).

[0061] As shown in Figure 9, the width W1 (length along the Y-axis) of the transparent portion 270 is smaller than the width W2 (length along the Y-axis) of the additional transparent portion 280. Viewed from the first restraining member 210 side, the width of the additional transparent portion 280 increases as it moves away from the first restraining member 210. The second restraining member 260 has a wall surface 269. The wall surface 269 forms a partial transparent portion 272. The wall surface 269 is inclined with respect to the Z-axis. Specifically, the wall surface 269a is inclined in the +Y direction with respect to the Z-axis. The wall surface 269b is inclined in the -Y direction with respect to the Z-axis.

[0062] As described above with reference to Figures 7 to 9, in the X-ray analysis system 1 according to this embodiment, the transmission portion 270 includes a plurality of point-shaped partial transmission portions 272. Therefore, the transmission portion 270 can be provided only at the necessary points. For example, if the transmission portion 270 is a hole that is restrained by the first restraining member 210, the number of holes can be reduced. Therefore, the strength and rigidity of the first restraining member 210 can be improved.

[0063] Furthermore, the width W1 (length along the Y-axis) of the transmission section 270 is smaller than the width W2 (length along the Y-axis) of the additional transmission section 280. In other words, the width W2 of the additional transmission section 280 on the X-ray detection side is larger than the width W1 of the transmission section 270 on the X-ray irradiation side. This makes it possible to obtain an average electrode state in the width direction (Y-axis direction) of the battery cell 600.

[0064] Furthermore, when viewed from the first restraint member 210 side, the width W2 of the additional transmission portion 280 increases as it moves away from the first restraint member 210. Therefore, the width of the additional transmission portion 280 is greater on the X-ray detection side than on the X-ray irradiation side.

[0065] Referring to Figure 10, an example of the simulation results of the in-plane distribution of the State of Charge (SOC) of a battery cell will be explained. SOC represents the charge level of the battery cell. Figure 10 is a diagram showing an example of the simulation results of the in-plane distribution of the SOC of a battery cell. In Figure 10, the X axis and Y axis represent the XY coordinates of the battery cell. In Figure 10, the coordinates X=0 and Y=0 represent the coordinates where the negative electrode terminal 614 is located. In Figure 10, the coordinates X=0 and Y=maximum represent the coordinates where the positive electrode terminal 612 is located. In Figure 10, regions R1 to R5 represent regions where the SOC is approximately the same. In Figure 10, regions R1 to R5 represent regions where the SOC is approximately the same. In Figure 10, the density of the dot pattern represents the value of SOC, and the higher the density of the dot pattern, the higher the SOC. That is, in Figure 10, the SOC is in the order of region R1 < region R2 < region R3 < region R4 < region R5.

[0066] As shown in Figure 10, the SOC is lowest in the regions where X=0, Y=0, and X=0, Y=the maximum value. As you move away from X=0, Y=0, and X=0, Y=the maximum value, the SOC gradually increases. In other words, as you move away from the positive terminal 612 and / or the negative terminal 614, the SOC gradually increases. To put it another way, as you move away from the positive terminal 612 and / or the negative terminal 614, the SOC shows a gradient in which it increases. In Figure 10, the SOC is in the order of region R1 < region R2 < region R3 < region R4 < region R5. For the sake of simplicity in the figure, the region is shown as being divided into five regions where the SOC is approximately the same, but in each of regions R1, R2, R3, R4, and R5, the SOC also shows a gradient in which it increases as you move away from the positive terminal 612 and / or the negative terminal 614. Thus, the State of Charge (SOC) of battery cells, especially large battery cells, generally tends to show variations within the plane. Therefore, it is preferable to analyze the characteristics of the electrode state of a battery cell, especially a large battery cell, by measuring multiple points within the plane. The X-ray analysis system 1 according to the embodiment of the present invention is capable of measuring the electrode state at multiple points within the plane of the SOC of a battery cell.

[0067] Referring to Figure 11, an example of X-ray analysis results of the State of Charge (SOC) of a battery cell will be described. Figure 11 is a diagram showing an example of X-ray analysis results of the SOC of a battery cell. Specifically, Figure 11 is a diagram showing an example of X-ray analysis results at multiple points in the plane of the SOC of a battery cell, using the sample holder 200 shown in Figure 2 in an X-ray analysis system according to an embodiment of the present invention (see Figure 1). In Figure 11, the horizontal axis represents time. In Figure 11, the vertical axis represents the diffraction angle 2Θ at which the X-ray intensity peak was detected.

[0068] As shown in Figure 11, the time course of the diffraction angle 2Θ at which the intensity peaks of X-rays measured at multiple points are detected differs for each measurement point. In other words, it was confirmed that the time course of the diffraction angle 2Θ at which the intensity peaks of the measured X-rays are detected differs depending on the position (XY coordinate) of the battery cell. Therefore, it is preferable to analyze the characteristics of the electrode state of the SOC of a battery cell, especially the SOC of a large battery cell, by measuring the diffraction angle 2Θ at which the intensity peaks of X-rays are detected at multiple points in the plane. The X-ray analysis system 1 according to the embodiment of the present invention is capable of measuring the electrode state at multiple points in the plane of the SOC of a battery cell.

[0069] The X-ray analysis system 1 according to this embodiment provides the following effects.

[0070] (1) In the X-ray analysis system 1, the sample holder 200 has a transmission section 270. The transmission section 270 can transmit X-rays to multiple points P on the battery cell 600. Therefore, X-rays can be irradiated to multiple points P in the plane of the battery cell 600 and the transmitted X-rays can be analyzed. As a result, even if there is variation from place to place in the plane of the battery cell 600, the electrode state (e.g., SOC) can be appropriately observed. Therefore, the electrode state distribution in the plane of the battery cell 600 during charging and discharging can be appropriately observed.

[0071] (2) In the X-ray analysis system 1, the transmission portion 270 includes a plurality of point-shaped partial transmission portions 272. Therefore, the transmission portion 270 can be provided only at the necessary points. For example, if the transmission portion 270 is a hole that is restrained by the first restraining member 210, the number of holes can be reduced. Therefore, the strength and rigidity of the first restraining member 210 can be improved.

[0072] (3) In the X-ray analysis system 1, the transmission part 270 has a wave shape, and therefore, the transmission part 270 can transmit X-rays to multiple points P on the battery cell 600 over a wide area in the lateral (X-axis direction) and vertical (Y-axis direction) directions of the battery cell 600. Therefore, the electrode state can be observed over a wide area in the plane of the battery cell 600. As a result, the electrode state can be observed appropriately.

[0073] (4) In the X-ray analysis system 1, if the transmission section 270 is a gap, the force applied to the battery cell 600 may vary in the plane. However, in the sample holder 200, the cushion member 220 is placed between the first restraining member 210 and the battery cell 600. Therefore, the force applied to the battery cell 600 can be equalized.

[0074] (5) In the X-ray analysis system 1, the transmission portion 270 is provided in the thin-walled portion 217. Therefore, the strength and rigidity of the first restraint member 210 can be improved while suppressing X-ray absorption in the first restraint member 210.

[0075] (6) In the X-ray analysis system 1, the width W1 (length along the Y-axis) of the transmission section 270 is smaller than the width W2 (length along the Y-axis) of the additional transmission section 280. That is, the width W2 of the additional transmission section 280 on the X-ray detection side is larger than the width W1 of the transmission section 270 on the X-ray irradiation side. This makes it possible to obtain the average electrode state in the width direction (Y-axis direction) of the battery cell 600.

[0076] (7) In the X-ray analysis system 1, when viewed from the first restraint member 210 side, the width W2 of the additional transmission portion 280 increases as it moves away from the first restraint member 210. Therefore, the width of the additional transmission portion 280 is greater on the X-ray detection side than on the X-ray irradiation side.

[0077] (8) In the X-ray analysis system 1, the holding device 300 switches the irradiation position P to multiple points, and the charging / discharging device 400 charges and discharges the battery cell 600 at each of the multiple points using the same pattern from the same charge state, so that the detection device 500 detects the X-rays X2 that pass through the sample holder 200 at each of the multiple points. Therefore, X-rays can be irradiated at multiple points P in the plane of the battery cell 600 and the transmitted X-rays can be analyzed. As a result, even if there is variation from place to place in the plane of the battery cell 600, the electrode state (e.g., SOC) can be appropriately observed. Therefore, the electrode state distribution in the plane of the battery cell 600 during charging and discharging can be appropriately observed.

[0078] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications and variations are possible. [Explanation of Symbols]

[0079] 200 sample holders 210 First restraining member 213 X-ray irradiated area 216 Thick wall part 217 Thin-walled section 220 Cushioning material 260 Second restraining member 266 Thick wall part 267 Thin-walled section 269, 269a, 269b Wall surfaces 270 Transparent part 272 Partially transparent part 280 Additional transparent section 300 Holding device 400 Charging and discharging equipment 500 detection devices 600 battery cells 610 battery 620 Laminate

Claims

1. An X-ray analysis system for obtaining analytical data by irradiating a battery cell, which comprises a battery and a laminate housing the battery, with X-rays, A sample holder capable of restraining the aforementioned battery cell, A holding device that holds the sample holder and can switch the irradiation position which indicates the position in which the X-rays are irradiated onto the battery cell restrained by the sample holder, A charging and discharging device for charging and discharging the battery cell restrained by the sample holder, Equipped with, The sample holder is an X-ray analysis system having a transmission section that allows X-rays to pass through multiple points on the battery cell.

2. The X-ray analysis system according to claim 1, wherein the transmission portion includes a plurality of point-shaped partial transmission portions.

3. The X-ray analysis system according to claim 1, wherein the transmission portion has a wave shape.

4. The aforementioned sample holder is The first restraining member is irradiated with the aforementioned X-rays and has the aforementioned transmission portion provided, A second restraint member to which the X-rays that have passed through the first restraint member are irradiated, A cushioning member is disposed between the first restraining member and the battery cell, It has, The X-ray analysis system according to claim 1 or claim 2, wherein the sample holder restrains the battery cell by sandwiching it from both sides with the first restraining member and the second restraining member.

5. The first restraining member has an X-ray irradiation portion that is irradiated with X-rays from the irradiation direction, The first restraining member is, Thick-walled section, A thin-walled portion having a shorter length in the direction of irradiation than the thick-walled portion, It has, The X-ray analysis system according to claim 4, wherein the transmission portion is provided in the thin-walled portion.

6. The second restraining member has an additional penetrating portion through which the X-rays that have passed through the penetrating portion pass, The permeable portion is a gap formed in the first restraining member, The additional permeable portion is a gap formed in the second restraining member, The X-ray analysis system according to claim 4, wherein the width of the transmission portion is smaller than the width of the additional transmission portion.

7. The first restraining member has an X-ray irradiation portion that is irradiated with X-rays from the irradiation direction, The second restraining member has an additional penetrating portion through which the X-rays that have passed through the penetrating portion pass, The additional permeable portion is a gap formed in the second restraining member, The X-ray analysis system according to claim 4, wherein, when viewed along the irradiation direction, the width of the gap formed in the second restraining member increases as it moves away from the first restraining member.

8. The device further comprises a detection device that detects the X-rays passing through the sample holder and acquires data for X-ray analysis. The X-ray analysis system according to claim 1 or 2, wherein the holding device switches the irradiation position to a plurality of points, and the charging / discharging device charges and discharges the battery cell at each of the plurality of points in the same pattern from the same charge state, so that the detection device detects the X-rays passing through the sample holder at each of the plurality of points and obtains the electrode state distribution during charging and discharging.

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