Secondary battery probe

Abstract

The invention provides a probe for a secondary battery, which can reduce contact resistance between the probe for the secondary battery and the secondary battery. A probe (1) for a secondary battery is a probe for a secondary battery (50) including a first pole (51) and a second pole (52) having different polarities on one side in the axial direction of a cylindrical shape, the second pole (52) being arranged in a ring shape so as to surround the first pole (51). A probe (1) for a secondary battery is provided with a ring-shaped electrode (10) that has a through-hole (11a) that avoids interference with a first electrode (51) and that is in contact with a second electrode (52), and a second spring (22) that biases the electrode (10) toward the second electrode (52).

Description

Technical Field

[0001] The present invention relates to a probe for a secondary battery. Background Art

[0002] Conventionally, there are well-known testing devices for testing the charge and discharge characteristics of secondary batteries, etc. For example, the device disclosed in Patent Document 1 charges and discharges a secondary battery in response to the voltage between the positive and negative electrodes of the secondary battery.

[0003] Patent Document 1: Japanese Patent Application Publication No. 2016-50800 Summary of the invention In the test of the secondary battery as described above, the probe is brought into contact with each of the positive electrode and the negative electrode. As a probe for a secondary battery, a pin-shaped probe is generally used. When a pin-shaped probe is used, the contact area between the positive electrode or the negative electrode and the probe is insufficient, and there is room for improvement. Moreover, when the probe is tilted relative to the secondary electrode, etc., it may not be possible to make the probe fully contact the positive electrode or the negative electrode. In particular, there are secondary batteries in which both the positive electrode and the negative electrode are arranged on one end face in the axial direction. In such a secondary battery, one pole is arranged in a ring shape in a manner surrounding the other pole. The width of the ring-shaped pole tends to become narrow, and the contact problem with the probe becomes particularly significant.

[0004] In view of the above, an object of the present invention is to reduce the contact resistance between a probe and a secondary battery.

[0005] The secondary battery probe of the present invention is a probe for a secondary battery in which a first pole and a second pole are arranged on an end face of one side in an axial direction, and the second pole is formed in a ring shape so as to surround the first pole and has a polarity different from that of the first pole. The secondary battery probe includes a ring-shaped electrode and an elastic component, wherein the ring-shaped electrode has a through hole to avoid interference with the first pole, contacts the second pole, and the elastic component applies force to the electrode toward the second pole.

[0006] (Effects of the Invention) According to the secondary battery probe, the contact resistance with the secondary battery can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 It is a schematic perspective view showing a secondary battery probe isolated from a secondary battery.

[0008] Figure 2 1 is a schematic perspective view showing a secondary battery probe in contact with a secondary battery.

[0009] Figure 3 This is a bottom view of the electrode viewed from the contact surface side of the contact, showing the mounted state of the contact and the terminal.

[0010] Figure 4 is from Figure 3 Side view of the electrode viewed from the direction of arrow A.

[0011] Figure 5 It is a cross-sectional view showing the detailed structure of the first electrode and the state of being mounted on the mounting stage.

[0012] Figure 6 It is a cross-sectional view showing the detailed structure of the second electrode and the state of being mounted on the mounting table.

[0013] Figure 7 is a partial cross-sectional view showing a state in which the first electrode contacts the first pole.

[0014] Figure 8 is a partial cross-sectional view showing a state where the second electrode contacts the second pole.

[0015] Fig. 9 It is a schematic perspective view showing a probe for a secondary battery according to a modification. DETAILED DESCRIPTION

[0016] Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings. Figure 1 It is a schematic perspective view showing the secondary battery probe 1 isolated from the secondary battery 50 . Figure 2 1 is a schematic perspective view showing the secondary battery probe 1 in contact with the secondary battery 50 .

[0017] like Figure 1 , Figure 2 As shown, the secondary battery probe 1 is a probe for a secondary battery 50 in which a first pole 51 and a second pole 52 are arranged on one end surface in the axial direction, and the second pole 52 is formed in a ring shape so as to surround the first pole 51 and has a polarity different from that of the first pole 51. The secondary battery probe 1 includes a ring-shaped electrode 10, and the ring-shaped electrode 10 has a through hole 11a to avoid interference with the first pole 51, and contacts the second pole 52, and the second spring 22 applies force to the electrode 10 toward the second pole 52. The force direction of the second spring 22 is referred to as "force direction B". The second spring 22 is an example of an elastic member.

[0018] The secondary battery probe 1 is used, for example, for a test such as a charge and discharge characteristic test of a secondary battery 50. The annular electrode 10 contacts the annular second pole 52, and the second spring 22 forces the electrode 10 toward the second pole 52. In this way, the electrode 10 is electrically connected to the second pole 52. The electrode 10 is electrically connected to a measuring instrument (not shown) for testing the secondary battery 50 via wiring. That is, the electrode 10 contacts the second pole 52, thereby electrically connecting the second pole 52 to the measuring instrument.

[0019] Examples of the secondary battery 50 include a sealed nickel-cadmium storage battery, a sealed nickel-metal hydride storage battery, a lithium-ion storage battery, a manganese dioxide lithium storage battery, and a cobalt oxide lithium carbon storage battery.

[0020] In this example, the secondary battery 50 is cylindrical. The first pole 51 is the positive pole, and the second pole 52 is the negative pole. The secondary battery 50 includes a housing, a cover, a positive electrode plate, a negative electrode plate, a separator, an electrolyte, and a safety valve. The positive electrode plate and the negative electrode plate are housed in the housing in a state of isolation with the separator sandwiched therebetween. The housing is cylindrical with a bottom. The housing and the cover are fitted together via an insulator to form a closed container. The electrolyte is filled in the closed container. The safety valve is provided on the cover to release the internal pressure when the internal pressure in the closed container becomes high.

[0021] The cover includes a first pole 51. The shell includes a second pole 52. The shell is a bottomed cylindrical shape, which is open in one direction of the axial direction. The cover closes the opening of the shell. The first pole 51 is arranged in the center of the cover. The outer peripheral edge of the shell that divides the opening is the second pole 52. That is, the first pole 51 and the second pole 52 are arranged on the end face of one side of the axial direction of the secondary battery 50. The first pole 51 is arranged in the center of the end face, and the second pole 52 is arranged on the outer peripheral edge of the end face.

[0022] As the charge and discharge characteristic test of the secondary battery 50, for example, there can be cited a capacity test, a high rate discharge characteristic test, a low temperature discharge characteristic test, an overcharge characteristic test, a capacity preservation characteristic test, a long-term storage characteristic test, a durability characteristic test, a safety valve action characteristic test, a vibration resistance characteristic test, and an impact resistance characteristic test.

[0023] The electrode 10 includes a contact 11 and a terminal 12, wherein the contact 11 contacts the second electrode 52. The terminal 12 is annular and flat, and is electrically connected to the contact 11. In this example, the electrode 10 includes two terminals 12.

[0024] The contact 11 is made of a conductive metal, for example, a gold-plated metal plate. The contact 11 has a through hole 11a in its central portion. The contact 11 is formed in a ring shape corresponding to the second pole 52. "Corresponding to the second pole 52" means that when viewed in the force direction B, it substantially covers the entire circumference of the second pole 52. In this example, the contact 11 is formed in a circular ring shape. That is, the inner diameter of the contact 11 is smaller than the diameter of the second pole 52, and the outer diameter of the contact 11 is larger than the diameter of the second pole 52. In a plan view (i.e., when viewed in the force direction B), the contact 11 fully covers the second pole 52.

[0025] The contact member 11 includes a contact surface 11b and a mounting surface 11c, wherein the contact surface 11b contacts the second pole 52, and the mounting surface 11c is located on the side opposite to the contact surface 11b. The contact surface 11b may also have a concave-convex shape. The concave-convex shape is formed, for example, by providing a mesh or lattice-shaped groove. In addition, the concave-convex shape may also be formed by knurling or sandblasting. In addition, a detachable mesh component may also be provided as the concave-convex shape.

[0026] The terminal 12 has a cylindrical overall shape. The terminal 12 is a terminal pin. The terminal 12 has an electrical contact point disposed at one end in the axial direction. The terminal 12 is mounted on the contact piece 11 in a state where the contact point contacts the contact piece 11.

[0027] Figure 3 It is a bottom view of the electrode 10 viewed from the contact surface 11 b side of the contact 11 , showing the mounted state of the contact 11 and the terminal 12 . Figure 4 is from Figure 3 A side view of the electrode 10 viewed from the direction of arrow A. Figure 3 , Figure 4 As shown, two terminals 12 are mounted on the mounting surface 11c of the contact 11. The two terminals 12 are arranged at positions symmetrical with respect to the center 11p of the contact 11. That is, the two terminals 12 are arranged at positions equidistant from the center 11p of the contact 11 in the circumferential direction.

[0028] The terminal 12 is fixed to the contact 11 with a screw 16. Specifically, the screw 16 passes through the through hole 11d from the contact surface 11b of the contact 11 and is screwed into the threaded hole 12a of the end surface of the terminal 12. In this way, the terminal 12 is electrically and mechanically connected to the contact 11. The terminal 12 is mounted on the mounting surface 11c in a manner extending in a direction orthogonal to the mounting surface 11c. The head of the screw 16 is embedded in the countersunk hole of the through hole 11d of the contact 11, and the head of the screw 16 is flush with the contact surface 11b or is further inside than the contact surface 11b. The terminal 12 is fixed with two screws 16. The two screws 16 are located between the Figure 3 The two dotted lines are shown on both sides of the contact area with the second pole 52. In this way, the screw 16 can be prevented from contacting the second pole 52. It should be noted that the terminal 12 can also be fixed to the contact member 11 by welding instead of the screw 16.

[0029] A wiring is connected to the terminal 12. The wiring is connected to a measuring instrument for testing of the secondary battery 50. That is, the contact 11 is electrically connected to the measuring instrument via the terminal 12 and the wiring.

[0030] like Figure 1 , Figure 2As shown, the probe 1 for a secondary battery is mounted on the mounting table 31. That is, the probe 1 for a secondary battery is used in a state of being mounted on the mounting table 31. The secondary battery 50 is arranged between the mounting table 31 and the support table 32. At this time, the direction in which the mounting table 31 and the support table 32 face each other is consistent with the axial direction of the secondary battery 50. The end surface of the secondary battery 50 in the axial direction, which is provided with the first pole 51 and the second pole 52, faces the mounting table 31, and the end surface of the secondary battery 50 on the opposite side of the axial direction contacts the support table 32.

[0031] The mounting base 31 supports the electrode 10 movably in a prescribed force direction B. Specifically, the mounting base 31 supports the terminal 12 movably in the force direction B. The mounting base 31 has a second mounting hole 31b into which the terminal 12 is inserted. The second mounting hole 31b penetrates the mounting base 31 in the force direction B. Since the electrode 10 has two terminals 12, the mounting base 31 also has two second mounting holes 31b. The terminal 12 can slide in the second mounting hole 31b in the force direction B. When the terminal 12 is mounted on the mounting base 31, the contact 11 is arranged on the secondary battery 50 side relative to the mounting base 31, and the contact surface 11b is substantially orthogonal to the force direction B.

[0032] The second spring 22 is a coil spring. The second spring 22 is embedded around the terminal 12. The second spring 22 and the terminal 12 are detachable. One end of the second spring 22 is locked by the terminal 12. The other end of the second spring 22 is locked by the mounting platform 31.

[0033] like Figure 2 As shown, when the probe 1 for a secondary battery is set on the secondary battery 50, the mounting table 31 is arranged close to the secondary battery 50 in such a manner that the second spring 22 is compressed and deformed. In this way, the second spring 22 applies force to the terminal 12 toward the secondary battery 50 by elastic force. Since the terminal 12 is mounted on the contact 11, the contact 11 is applied toward the secondary battery 50. As a result, the contact surface 11b of the contact 11 properly contacts the second pole 52 of the secondary battery 50.

[0034] In this example, the probe 1 for a secondary battery includes two second springs 22. The two springs 22 are arranged at positions that are symmetrical with respect to the center 11p of the contact 11. In other words, the two second springs 22 are arranged at positions that are equally spaced in the circumferential direction with respect to the center 11p of the contact 11. In this way, the elastic forces of the two second springs 22 act at positions that are symmetrical with respect to the center 11p of the contact 11.

[0035] The secondary battery probe 1 may further include an electrode 15 and a first spring 21. The electrode 15 is an electrode different from the electrode 10. The electrode 15 is an electrode that contacts the first pole 51 of the secondary battery 50. The first spring 21 applies force to the electrode 15 toward the first pole 51. That is, in the secondary battery probe 1, the probe for the first pole 51 and the probe for the second pole 52 are integrated. Hereinafter, the electrode 15 is also referred to as the "first electrode 15", and the electrode 10 is also referred to as the "second electrode 10".

[0036] The first electrode 15 is electrically connected to a measuring instrument for testing the secondary battery 50 via wiring. That is, the first electrode 15 is in contact with the first pole 51 to electrically connect the first pole 51 to the measuring instrument.

[0037] In this example, the first electrode 15 has the same structure as the terminal 12. The first electrode 15 has a columnar overall shape. The first electrode 15 is a terminal pin. The first electrode 15 has an electrical contact point arranged at one end in the axial direction. The first electrode 15 is supported by the mounting table 31 movably in the force direction B. The mounting table 31 has a first mounting hole 31a into which the first electrode 15 is inserted. The first mounting hole 31a penetrates the mounting table 31 in the force direction B. The first mounting hole 31a is arranged between the two second mounting holes 31b, and in detail, the first mounting hole 31a is arranged in the center of the two second mounting holes 31b. The first electrode 15 is slidable in the first mounting hole 31a in the force direction B. When the first electrode 15 is mounted on the mounting table 31, the contact point of the first electrode 15 is arranged on the secondary battery 50 side relative to the mounting table 31. The first electrode 15 is arranged on the inner side of the through hole 11a of the contact member 11. That is, the first electrode 15 is not in contact with the contact member 11, that is, it is not in contact with the second electrode 10.

[0038] The first spring 21 is a coil spring. The first spring 21 is embedded around the first electrode 15. The first spring 21 and the first electrode 15 are detachable. One end of the first spring 21 is locked by the first electrode 15. The other end of the first spring 21 is locked by the mounting base 31.

[0039] like Figure 2 As shown, when the secondary battery probe 1 is placed on the secondary battery 50, the mounting base 31 is placed close to the secondary battery 50 in such a way that the first spring 21 is compressed and deformed. In this way, the first spring 21 applies force to the first electrode 15 toward the secondary battery 50 due to the elastic force. As a result, the first electrode 15 properly contacts the first pole 51 of the secondary battery 50.

[0040] Figure 51 is a cross-sectional view showing the detailed structure of the first electrode 15 and the state of being mounted on the mounting table 31. The first electrode 15 has a first pin 101, a second pin 102 and a bushing 103. The first pin 101 is cylindrical. The second pin 102 is columnar. The bushing 103 is cylindrical. The first pin 101 is slidably inserted into the bushing 103. The second pin 102 is slidably inserted into the first pin 101. The first pin 101 and the second pin 102 are insulated.

[0041] In this example, the first spring 21 is integrated into the first electrode 15 . The first electrode 15 and the first spring 21 constitute a spring-type terminal pin. The first spring 21 is embedded in the outer periphery of the first pin 101 .

[0042] Specifically, the bushing 103 is formed of an insulator and supports the first pin 101 in a slidable manner in the biasing direction B.

[0043] The length direction of the first pin 101 is consistent with the force direction B. The first pin 101 has a first end 101a, which is one end in the length direction, and a second end 101b, which is the other end in the length direction. The first end 101a and the second end 101b protrude from the bushing 103, respectively. The first end 101a of the first pin 101 contacts the first electrode 15 during the test of the secondary battery 50. The second end 101b of the first pin 101 is connected to a measuring instrument via a wiring (not shown).

[0044] An external thread is formed in the outer peripheral surface of the first pin 101 near the second end 101b. Two nuts 104 are threadedly connected to the external thread of the first pin 101. The two nuts 104 are so-called double nuts. The movement of the first pin 101 to the first end 101a side is restricted by the contact of the nut 104 with the bushing 103. The nut 104 plays a role in preventing the first pin 101 from falling off from the bushing 103. It should be noted that by removing the nut 104 from the first pin 101, the first electrode 15 can be disassembled, and the first electrode 15, the first spring 21 and the mounting base 31 can be separated.

[0045] A step is formed near the first end 101a on the outer peripheral surface of the first pin 101. In the first pin 101, the portion on the first end 101a side is thicker than the step. The first spring 21 is arranged between the step of the first pin 101 and the bushing 103 when the first pin 101 is inserted into the bushing 103. One end of the first spring 21 is locked by the step of the first pin 101. The other end of the first spring 21 is locked by the bushing 103.

[0046] At this time, the first spring 21 is compressed and exerts elastic force in the extension direction. The first pin 101, i.e., the first electrode 15, is forced toward the first end 101a side in the force application direction B by the first spring 21. However, the movement of the first pin 101 is restricted at the position where the nut 104 contacts the bushing 103. When an external force acts on the first pin 101 toward the second end 101b side in the force application direction B, the first pin 101 moves toward the second end 101b side against the elastic force of the first spring 21.

[0047] A first inner bushing 301 and a second inner bushing 302 are arranged inside the first pin 101. The first inner bushing 301 and the second inner bushing 302 are formed of an insulator. The first inner bushing 301 is arranged inside the first pin 101 near the first end 101a. The entire first inner bushing 301 is accommodated in the first pin 101. The second inner bushing 302 is arranged inside the first pin 101 at the second end 102b. The second inner bushing 302 partially protrudes from the first pin 101.

[0048] The second pin 102 is slidably inserted into the first inner bushing 301 and the second inner bushing 302. One end of the second pin 102, i.e., the first end 102a, protrudes from the first end 101a of the first pin 101. The other end of the second pin 102, i.e., the second end 102b, protrudes from the second end 101b of the first pin 101. The first end 102a of the second pin 102 contacts the first electrode 51 when the secondary battery 50 is tested. The second end 102b of the second pin 102 is connected to a measuring instrument via a wiring (not shown).

[0049] A step is formed near the second end 102b on the outer peripheral surface of the second pin 102. The second pin 102 is thicker at the second end 102b side than the step. The step of the second pin 102 contacts the second inner bushing 302, thereby restricting the second pin 102 from moving toward the first end 102a side. That is, the second inner bushing 302 also functions to prevent the second pin 102 from falling off.

[0050] A ferrule 303 is fixed to the outer circumferential surface of the portion of the second pin 102 located inside the first pin 101. The ferrule 303 is formed of an insulator. The ferrule 303 is located inside the first pin 101 between the first inner bushing 301 and the second inner bushing 302. The ferrule 303 slides relative to the inner circumferential surface of the first pin 101.

[0051] The inner spring 401 is embedded in the outer periphery of the second pin 102. The inner spring 401 is a coil spring. The inner spring 401 is arranged between the second inner bushing 302 and the collar 303. At this time, the inner spring 401 is compressed and exerts elastic force in the extension direction. The second pin 102 is urged toward the first end 102a side in the force application direction B by the inner spring 401. However, at a position where the step of the second pin 102 contacts the second inner bushing 302, the movement of the second pin 102 is restricted. When an external force acts on the second pin 102 toward the second end 102b side in the force application direction B, the second pin 102 moves toward the second end 102b side against the elastic force of the inner spring 401.

[0052] The first spring 21 is incorporated in the first electrode 15 to urge the first pin 101 in the urging direction B. Thus, the first pin 101 is elastically displaceable in the urging direction B and stably contacts the first electrode 51 at a predetermined contact pressure.

[0053] The bushing 103 is inserted into the first mounting hole 31a of the mounting base 31. One end of the bushing 103 is locked by the first surface 31c of the mounting base 31. The other end of the bushing 103 is screwed by the nut 33 on the second surface 31d side of the mounting base 31. In this way, the bushing 103 is fixed to the first mounting hole 31a of the mounting base 31. When the bushing 103 is mounted on the mounting base 31, the first end 101a of the first pin 101, the first end 102a of the second pin 102, and the first spring 21 are arranged on the first surface 31c side relative to the mounting base 31.

[0054] Figure 6 1 is a cross-sectional view showing the detailed structure of the second electrode 10 and the state of being mounted on the mounting table 31. The terminal 12 has the same structure as the first electrode 15. That is, the terminal 12 has a first pin 101, a second pin 102 and a bushing 103. In this example, the second spring 22 is integrated into the terminal 12. The terminal 12 and the second spring 22 constitute a spring-type terminal pin. The second spring 22 is embedded in the outer periphery of the first pin 101. The first pin 101 is inserted into the bushing 103 in a state where it is urged toward the first end 101a side in the force direction B by the second spring 22. The second pin 102 is inserted into the first pin 101 in a state where it is urged toward the first end 102a side in the force direction B by the internal spring 401.

[0055] In detail, the bushing 103 supports the first pin 101 slidably in the force direction B. The first end 101a and the second end 101b of the first pin 101 protrude from the bushing 103 respectively. Two nuts 104 are screwed to the external threads near the second end 101b of the first pin 101. It should be noted that by removing the nuts 104 from the first pin 101, the terminal 12 can be disassembled, and the second electrode 10, the second spring 22 and the mounting base 31 can be separated.

[0056] The second spring 22 is arranged on the outer periphery of the first pin 101 between the step of the first pin 101 and the bushing 103. One end of the second spring 22 is stopped by the step of the first pin 101. The other end of the second spring 22 is stopped by the bushing 103. At this time, the second spring 22 is compressed and exerts elastic force in the extension direction. The first pin 101, i.e., the terminal 12, is forced toward the first end 101a side in the force direction B by the second spring 22. However, the movement of the first pin 101 is restricted at the position where the nut 104 contacts the bushing 103. When an external force acts on the first pin 101 toward the second end 101b side in the force direction B, the first pin 101 moves toward the second end 101b side against the elastic force of the second spring 22.

[0057] The second pin 102 is slidably inserted into the first inner bushing 301 and the second inner bushing 302 inside the first pin 101. One end of the second pin 102, namely the first end 102a, protrudes from the first end 101a of the first pin 101. Figure 6 In the embodiment, the second pin 102 is elastically displaced, and the first end 102a is flush with the first end 101a. The other end of the second pin 102, namely the second end 102b, protrudes from the second end 101b of the first pin 101.

[0058] The inner spring 401 is embedded in the outer periphery of the second pin 102. The inner spring 401 is arranged between the second inner bushing 302 and the collar 303. At this time, the inner spring 401 is compressed and exerts elastic force in the extension direction. The second pin 102 is urged toward the first end 102a side in the force application direction B by the inner spring 401. However, the movement of the second pin 102 is restricted at a position where the step of the second pin 102 contacts the second inner bushing 302. When an external force acts on the second pin 102 toward the second end 102b side in the force application direction B, the second pin 102 moves toward the second end 102b side against the elastic force of the inner spring 401.

[0059] The terminal 12 is provided with a contact 11, which is different from the first electrode 15. A threaded hole 12a is formed on the end surface of the first end 101a of the first pin 101 (see Figure 4). The contact 11 is mounted on the first end 101a of the first pin 101 via the screw 16. In this way, the first pin 101 is electrically and mechanically connected to the contact 11. Usually, the first end 102a of the second pin 102 protrudes from the first end 101a of the first pin 101 due to the force of the internal spring 401. The contact 11 is mounted on the first end 101a of the first pin 101, so that the second pin 102 is pressed toward the second end 102b side in the force direction B. That is, in a state where the contact 11 is mounted on the first pin 101, the second pin 102 is pressed to the contact 11 due to the elastic force of the internal spring 401. In this way, the second pin 102 is electrically and mechanically connected to the contact 11.

[0060] In this way, the second spring 22 is incorporated into the terminal 12 to apply force to the first pin 101 in the force application direction B. In this way, the first pin 101 can be elastically displaced in the force application direction B. In addition, since the contact 11 is mounted on the first pin 101 of the terminal 12, the second spring 22 applies force to the contact 11 in the force application direction B via the first pin 101. In this way, the contact 11 can be elastically displaced in the force application direction B.

[0061] The bushing 103 is inserted into the second mounting hole 31b of the mounting base 31. One end of the bushing 103 is locked by the first surface 31c of the mounting base 31. The other end of the bushing 103 is screwed by the nut 33 on the second surface 31d side of the mounting base 31. In this way, the bushing 103 is fixed to the second mounting hole 31b of the mounting base 31. In the state where the bushing 103 is fixed to the mounting base 31, the first end 101a of the first pin 101, the first end 102a of the second pin 102, the contact 11 and the second spring 22 are arranged on the first surface 31c side relative to the mounting base 31.

[0062] Next, a usage example of the secondary battery probe 1 will be described. Figure 7 1 is a partial cross-sectional view showing a state in which the first electrode 15 contacts the first pole 51 . Figure 8 1 is a partial cross-sectional view showing a state in which the second electrode 10 contacts the second pole 52 .

[0063] First, the secondary battery 50 is placed on the support table 32 . At this time, the end surface of the secondary battery where the first electrode 51 and the second electrode 52 are not placed contacts the support table 32 .

[0064] In this state, the mounting table 31 on which the secondary battery probe 1 is mounted is brought close to the end surface of the secondary battery 50 on which the first pole 51 and the second pole 52 are arranged. The moving direction of the mounting table 31, i.e., the secondary battery probe 1, is substantially the same as the force application direction B. Finally, the first electrode 15, specifically, the first pin 101 and the second pin 102 contact the first pole 51 of the secondary battery 50, and the second electrode 10, specifically, the contact 11 contacts the second pole 52 of the secondary battery 50. After the first electrode 15 and the second electrode 10 contact the first pole 51 and the second pole 52, respectively, the mounting table 31 still moves toward the secondary battery 50, and the first spring 21 and the second spring 22 are compressed.

[0065] Specifically, when the mounting table 31 approaches the secondary battery 50, the second pin 102 contacts the first electrode 51 in the first electrode 15, and then the second pin 102 is pushed into the first pin 101 against the elastic force of the internal spring 401. Figure 7 As shown, the first pin 101 contacts the first pole 51, and both the first pin 101 and the second pin 102 contact the first pole 51. From this state, the mounting base 31 further moves toward the secondary battery 50 against the elastic force of the first spring 21. The first spring 21 is further compressed. In this way, the first electrode 15 is urged toward the secondary battery 50 side in the force direction B due to the elastic force of the first spring 21 while contacting the first pole 51.

[0066] like Figure 8 As shown, in the second electrode 10, after the contact member 11 contacts the second pole 52, the mounting base 31 moves further toward the secondary battery 50 against the elastic force of the second spring 22. The second spring 22 is further compressed. In this way, the second electrode 10 is urged toward the secondary battery 50 in the force application direction B by the elastic force of the second spring 22 while contacting the second pole 52. It should be noted that Figure 2 As shown, the first pole 51 is located inside the through hole 11 a of the contact member 11 . That is, the contact member 11 does not contact the first pole 51 .

[0067] After the secondary battery probe 1 is set on the secondary battery 50, a test of the secondary battery 50 is performed. For example, the current of the secondary battery 50 is charged and discharged through the first pin 101 of each of the first electrode 15 and the second electrode 10, and the voltage of the secondary battery 50 is measured through the second pin 102 of each of the first electrode 15 and the second electrode 10. Such a test performed by the secondary battery probe 1 is a test performed using a so-called four-terminal measurement method. For example, the first pin 101 is a pin for current application. The second pin 102 is a pin for voltage measurement.

[0068] In a capacity test as an example of a charge-discharge characteristic test, first, a certain current is flowed into the secondary battery 50 for a predetermined time via the first electrode 15 and the second electrode 10 to charge. After the charging is completed, the secondary battery 50 is left for one hour. Then, the discharge of the secondary battery 50 is started. Specifically, the secondary battery 50 is continuously discharged with a certain current via the first electrode 15 and the second electrode 10 until a predetermined discharge end voltage is reached. After the discharge starts, the time until the predetermined discharge end voltage is reached is recorded.

[0069] According to the probe 1 for a secondary battery constructed in this way, the second electrode 10 is formed into a ring shape corresponding to the second pole 52. That is, the second electrode 10 fully covers the ring-shaped second pole 52. In this way, the second electrode 10 spans most of the circumferential direction of the second pole 52, preferably spans the entire circumference of the circumferential direction of the second pole 52, and contacts the second pole 52. Therefore, the contact area between the second electrode 10 and the second pole 52 is increased. At this time, the contact between the second electrode 10 and the first pole 51 can be avoided by forming the second electrode 10 into a ring shape having a through hole 11a. That is, the second electrode 10 can increase the contact area with the second pole 52 while avoiding contact with the first pole 51.

[0070] Furthermore, since the second spring 22 applies force to the second electrode 10 toward the second pole 52, the contact pressure of the second electrode 10 to the second pole 52 can be increased. In this way, the second electrode 10 stably contacts the second pole 52. In addition, even if the secondary battery 50 and the second electrode 10 are relatively tilted, the second spring 22 can elastically displace the second electrode 10, and the contact between the second electrode 10 and the second pole 52 can be maintained.

[0071] This can reduce the contact resistance between the secondary battery probe 1 and the secondary battery 50. Since the contact resistance between the secondary battery probe 1 and the secondary battery 50 can be reduced, a large current can be applied to the secondary battery 50 through the secondary battery probe 1 while suppressing heat generation at the contact portion between the secondary battery probe 1 and the secondary battery 50.

[0072] In addition, the secondary battery probe 1 has a plurality of (two in this example) second springs 22, and the plurality of second springs 22 are arranged at positions symmetrical to the center 11p of the contact 11, that is, at positions equally spaced in the circumferential direction relative to the center 11p of the contact 11. In this way, a force can be uniformly applied to the contact 11 in the circumferential direction. As a result, the second electrode 10 can be brought into contact with the second pole 52 more stably.

[0073] Furthermore, the second electrode 52 of the secondary battery 50 is formed in an annular shape in the same plane. By forming the contact 11 in an annular and flat plate shape, the contact 11 can be brought into contact with the annular second electrode 52 over substantially the entire circumference.

[0074] Since the contact surface 11b of the contact member 11 has a concavo-convex shape, the contact surface 11b of the contact member 11 can be made to contact the second pole 52 at multiple points compared to when the contact surface is smooth. For example, when the second pole 52 is formed in a ridge shape, if the contact surface of the contact member 11 is smooth, the contact member 11 may only contact the ridge line of the second pole 52. In contrast, the contact surface 11b having a concavo-convex shape can contact not only the ridge line of the second pole 52, but also the portion other than the ridge line. In this way, the contact area between the second electrode 10 and the second pole 52 can be further increased.

[0075] Since the second spring 22 and the second electrode 10 are detachable, when the second electrode 10 is consumed, the second electrode 10 can be easily replaced.

[0076] Since the second spring 22 is coaxially embedded in the terminal 12, the second spring 22 can be integrated with the terminal 12, and the space for installing the second spring 22 can be reduced. In addition, the terminal 12 acts as a guide for the second spring 22, which is a rotation spring. In this way, the elastic force of the second spring 22 can be stably applied to the second electrode 10.

[0077] Furthermore, the second spring 22 is incorporated as a spring-type terminal pin into the terminal 12. In other words, the spring of the spring-type terminal pin is used as the second spring 22 to bias the contact 11. That is, the structure of the second electrode 10 can be simplified by utilizing the spring of the spring-type terminal pin for maintaining stable contact.

[0078] Similarly, since the first electrode 15 is urged toward the first pole 51 by the first spring 21, the contact pressure of the first electrode 15 on the first pole 51 is increased. In this way, the first electrode 15 stably contacts the first pole 51. In addition, even if the secondary battery 50 and the first electrode 15 are relatively tilted, the first spring 21 can elastically displace the first electrode 15, and the contact between the first electrode 15 and the first pole 51 is maintained.

[0079] (Variation Example) Fig. 91 is a schematic three-dimensional diagram showing a secondary battery probe 1A according to a modified example. The secondary battery probe 1A differs from the secondary battery probe 1 in the structure of the electrode. The following description will focus on the structure of the secondary battery probe 1A that is different from the secondary battery probe 1. It should be noted that in the secondary battery probe 1A, the same symbols as those of the secondary battery probe 1 are the same structures as those of the secondary battery probe 1, and therefore the description thereof will be omitted.

[0080] The electrode 10A (hereinafter also referred to as the "second electrode 10A") of the secondary battery probe 1A has a contact 11. The second electrode 10A does not have the terminal 12 of the secondary battery probe 1. The wiring 17 is directly electrically connected to the contact 11 of the second electrode 10A. The wiring 17 is connected to a measuring instrument not shown. The wiring 17 may include, for example, a wiring for current application and a wiring for voltage measurement. In this way, the second electrode 10A is annular and flat.

[0081] The second spring 22 is arranged between the second electrode 10A and the mounting base 31 without the terminal 12. The second spring 22 and the second electrode 10A may be detachable.

[0082] The secondary battery probe 1A, like the secondary battery probe 1 , further includes a first electrode 15 for the first pole 51 and a first spring 21 .

[0083] According to the secondary battery probe 1A, since the second electrode 10A is annular and flat, when the second electrode 10A is brought into contact with the second electrode 52, the second electrode 10A can be brought into contact to cover substantially the entire circumference of the second electrode 52. As a result, the contact area of ​​the second electrode 10A with the second electrode 52 can be increased.

[0084] Furthermore, the electrical connection of the contact 11 is achieved by direct connection of the wiring 17. The second spring 22 is arranged on the contact 11 independently of the electrical connection of the contact 11. Therefore, the mechanical connection of the contact 11 by the second spring 22 and the electrical connection of the contact 11 by the wiring 17 can be maintained separately.

[0085] It should be noted that, although descriptions of other structures, functions, and effects are omitted, the description of the secondary battery probe 1 can be used for the description of the secondary battery probe 1A.

[0086] (Other embodiments) As described above, the embodiments are described as examples of the technology disclosed in this application. However, the technology disclosed in the present invention is not limited thereto, and can also be applied to embodiments that have been appropriately changed, replaced, added, omitted, etc. Furthermore, the various constituent elements described in the embodiments can also be combined as new embodiments. Furthermore, the constituent elements recorded in the drawings and detailed descriptions include not only the constituent elements necessary for solving the problem, but also constituent elements that are not necessary for solving the problem in order to exemplify the technology. Therefore, it should not be immediately assumed that those non-essential constituent elements are necessary just because they are recorded in the drawings and detailed descriptions.

[0087] For example, in the secondary battery 50, the first electrode 51 may be a negative electrode and the second electrode 52 may be a positive electrode. The secondary battery 50 may be in a rectangular tube shape instead of a cylindrical shape.

[0088] The secondary battery probe 1 or 1A may not include the first electrode 15 for the first pole 51 and the first spring 21 . That is, the secondary battery probe 1 or 1A may include only the second electrode 10 or 10A for the second pole 52 and the second spring 22 .

[0089] The elastic member for urging the electrode is not limited to a coil spring like the second spring 22, and may be rubber or a leaf spring, etc. Similarly, the first spring 21 is not limited to a coil spring, and may be rubber or a leaf spring, etc.

[0090] In the probe 1 for secondary battery, the second spring 22 is integrated into the terminal 12, but it is not limited thereto. For example, the second spring 22 may be arranged without being embedded in the terminal 12. The second spring 22 and the terminal 12 can be maintained separately by separating the second spring 22 and the terminal 12, so that maintenance becomes easy. For example, the second spring 22 and the terminal 12 may be arranged alternately and at equal intervals in the circumferential direction relative to the center 11p of the contact 11.

[0091] The secondary battery probe 1 includes two terminals 12 , but the number of the terminals 12 may be 1 or 3 or more. It is noted that the plurality of terminals 12 are preferably arranged at equal intervals in the circumferential direction with respect to the center 11 p of the contact 11 .

[0092] The number of the second springs 22 may be one or more than three. It is preferred that the plurality of second springs 22 are arranged at equal intervals in the circumferential direction relative to the center 11p of the contact 11. In this way, the second springs 22 can uniformly apply force to the contact 11 in the circumferential direction. As a result, the stability of the contact 11 to the second pole 52 is improved. Alternatively, the second spring 22 may be a coil spring having a through hole 11a having a diameter greater than that of the contact 11, and is substantially coaxially arranged with the contact 11. In this case, the entire circumferential direction of the contact 11 can be pressed by one second spring 22.

[0093] The shape of the contact 11 is not limited to a circular ring, and may be any ring shape as long as it corresponds to the second pole 52. For example, the contact 11 may also be a polygonal ring.

[0094] Although the contact piece 11 is in the form of a flat plate, the contact piece 11 may also be in the form of a tube. In that case, at least the portion of the contact piece 11 that contacts the second pole 52 may also be in the form of a truncated cone that expands in a manner that the diameter gradually increases. In this way, the second pole 52 can more easily contact the inner circumference of the cylindrical contact piece 11.

[0095] The terminal 12 is not limited to the above structure. For example, the terminal 12 may have the first pin 101 but not the second pin 102. In this case, a test using a so-called two-terminal measurement method may be performed.

[0096] The technology of the present invention is summarized below.

[0097] [1] A secondary battery probe 1, 1A is a probe for a secondary battery 50 in which a first pole 51 and a second pole 52 are arranged on one end surface in the axial direction, and the second pole 52 is formed in a ring shape so as to surround the first pole 51 and has a polarity different from that of the first pole 51. The secondary battery probe 1, 1A includes a ring-shaped electrode 10, 10A and a second spring 22 (elastic member), wherein the ring-shaped electrode 10, 10A has a through hole 11a to avoid interference with the first pole 51 and contacts the second pole 52, and the second spring 22 (elastic member) applies force to the electrode 10, 10A toward the second pole 52.

[0098] According to this structure, for example, when the secondary battery probe 1, 1A is brought into contact with the secondary battery 50 in order to test the secondary battery 50, since the electrode 10, 10A is formed in a ring shape corresponding to the second pole 52, the contact area with the second pole 52 can be increased. In addition, since the electrode 10, 10A has the through hole 11a, it is possible to contact the second pole 52 while avoiding contact with the first pole 51. In addition, since the second spring 22 applies force to the electrode 10, 10A toward the second pole 52, the contact of the electrode 10, 10A with the second pole 52 can be stabilized. For example, even when the electrode 10, 10A is somewhat tilted relative to the secondary battery 50, the electrode 10, 10A is displaced by the elastic deformation of the second spring 22 and maintains contact with the second pole 52. As a result, the contact resistance between the secondary battery probe 1, 1A and the secondary battery 50 can be reduced.

[0099] [2] In the secondary battery probe 1A described in [1], the electrodes 10 and 10A are in the form of a flat plate.

[0100] This structure can further increase the contact area between the electrode 10, 10A and the second electrode 52. Specifically, the second electrode 52 of the secondary battery 50 extends in a ring shape in one plane. By making the electrode 10, 10A flat, it is possible to contact the second electrode 52 over almost the entire circumference.

[0101] [3] In the secondary battery probe 1 or 1A described in [1] or [2], the electrode 10 or 10A has a contact surface 11 b that contacts the second electrode 52 , and the contact surface 11 b has a concavo-convex shape.

[0102] According to this structure, since the contact surface 11b of the electrodes 10 and 10A has a concave-convex shape, the contact surface 11b of the electrodes 10 and 10A can contact the second pole 52 at multiple points compared to when the contact surface 11b of the electrodes 10 and 10A is smooth, and the contact area between the electrodes 10 and 10A and the second pole 52 can be further increased.

[0103] [4] In the secondary battery probe 1 or 1A described in any one of [1] to [3], the second spring 22 and the electrode 10 or 10A are detachable.

[0104] According to this configuration, when the electrode 10 or 10A is worn out, the electrode 10 or 10A can be separated from the second spring 22 , thereby making it easier to maintain the electrode 10 or 10A.

[0105] [5] In the secondary battery probe 1 described in any one of [1] to [4], the electrode 10 includes a contact 11 and a terminal 12 , wherein the contact 11 contacts the second electrode 52 and is annular and flat, and the terminal 12 is electrically connected to the contact 11 .

[0106] According to this structure, the terminal 12 can also be used as a guide for the second spring 22 .

[0107] (Explanation of Symbols) 1, 1A-probe for secondary battery; 10, 10A-electrode; 11-contact piece; 11a-through hole; 11b-contact surface; 12-terminal; 22-second spring (elastic component); 50-secondary battery; 51-first pole; 52-second pole.

Claims

1. A probe for a secondary battery, wherein a first pole and a second pole are arranged on one end surface in an axial direction, the second pole is formed in a ring shape so as to surround the first pole and has a different polarity from the first pole, characterized in that: The secondary battery probe includes a ring-shaped electrode and an elastic member. The ring-shaped electrode has a through hole to avoid interference with the first pole and contacts the second pole. The elastic member applies force to the electrode toward the second pole.

2. The probe for a secondary battery according to claim 1, characterized in that: The electrode is in the form of a flat plate.

3. The probe for a secondary battery according to claim 2, characterized in that: The electrode has a contact surface contacting the second electrode, The contact surface has a concavo-convex shape.

4. The probe for a secondary battery according to any one of claims 1 to 3, characterized in that: The elastic component and the electrode are detachable.

5. The probe for a secondary battery according to claim 1, characterized in that: The electrode includes a contact piece and a terminal. The contact piece contacts the second pole and is in a ring shape and a flat plate shape. The terminal is electrically connected to the contact piece.

Images