JP2005285515A - Alkali enclosed secondary battery and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alkali sealed secondary battery capable of keeping high reliability for a long time also in an application requiring high current output, and its manufacturing method. <P>SOLUTION: The battery 1 has six electrode units 17 in an internal space formed of a case 10 and a lid 11, and the case 10 is partitioned to six cell chambers 102 with partition walls 101. Each of six electrode units 17 is stored in each of the six partitioned cell chambers 102 of the case 10, and they are interconnected in series. A notch 111a is formed in a partial region of the partition walls 111 of the lid 11, and allows gas circulation between cell chambers 102. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an alkaline sealed secondary battery and a method for manufacturing the same, and more particularly to a technique for improving reliability when applied to a large current application.

  In recent years, while development of hybrid electric vehicles (HEVs) and electric vehicles (Pure-Electric Vehicles) has progressed, the development of sealed secondary batteries used therefor has also been promoted. In particular, an alkaline sealed secondary battery (hereinafter simply referred to as “battery”) such as a nickel-hydrogen (Ni-MH) secondary battery has a higher energy density than a lead battery, and is a battery mounted on the vehicle or the like. Suitable as

A battery used in these vehicles has a configuration in which a plurality of spiral electrode bodies are connected in parallel to form one cell unit, and each of the plurality of cell units is housed in a partitioned cell chamber in a resin exterior body. It has been developed (see, for example, Patent Document 1). This sealed battery has a configuration in which a plurality of cell units are connected in series, and a plurality of spiral electrode bodies constituting each cell unit are wound with a liquid retaining sheet to hold an electrolyte solution.
JP 2002-324568 A

  However, the conventional battery represented by the above-mentioned Patent Document 1 has a problem that output variation is significant when charging and discharging are repeated over a long period of time, and the life is short. This is considered to be due to the following reason. That is, in the battery according to Patent Document 1, each cell unit has a configuration in which a plurality of electrode bodies are connected in parallel by current collector plates, and the current collector plates are connected in series. At the time of taking out, in one cell unit, an electrode body closer to the connection point connecting each cell unit flows a higher current, and an electrode body far from the connection point flows a lower current. Therefore, in the battery according to Patent Document 1, there is a variation in the current flowing through each electrode body in the cell unit, thereby causing a variation in the consumption of the electrolyte. Therefore, the battery of Patent Document 1 has a problem that, when used in an application requiring a large current for a long time, the output variation of the battery becomes remarkable and the life is shortened.

  The present invention has been made to solve such a problem, and provides an alkaline sealed secondary battery capable of maintaining high reliability for a long period of time even for applications requiring a large current output, and a method for manufacturing the same. The purpose is to do.

In order to achieve the above object, the present invention has the following features. The “battery” used below indicates an alkaline sealed secondary battery as described above.
(1) A battery having a plurality of electrode bodies wound in a state in which positive and negative bipolar plates are arranged to face each other with a separator interposed therebetween, and having an exterior body that houses the plurality of electrode bodies, The region for storing the electrode body is divided into a plurality of cell chambers according to the number of electrode bodies stored with a partition wall, and each of the plurality of electrode bodies has a cell chamber in a state where the winding shaft intersects the partition wall. It is characterized by being stored separately and connected in series with each other.

(2) The battery according to (1) above, wherein the exterior body includes a case and a lid, and gas flow between a plurality of cell chambers is provided in at least one of the case and the lid. It is characterized in that a gas distribution channel that enables the above is provided.
(3) In the battery according to (1) or (2) above, in each of the plurality of electrode bodies, the positive electrode plate and the negative electrode plate located on both end faces in the winding axis direction are arranged in the radial direction of the electrode body. Current collecting members each having a protruding portion extending to the partition wall are joined to each other, and the partition wall of the exterior body is close to the portion near the end of the protruding portion when the electrode body is stored in each cell chamber. A through hole is formed, and the adjacent electrode bodies are connected in series by joining the protruding portions of the current collecting members positioned across the partition wall through the through hole. To do.

  (4) The battery according to (2) or (3) above, wherein the partition wall has a form corresponding to each other and is formed in both the case and the lid, and the gas flow path is a partition in the lid. A part of the wall is notched and formed, and this lid has a safety valve for releasing the internal gas to the outside when the pressure inside the exterior body exceeds a predetermined pressure. Is provided in a state of being connected to the gas flow path.

(5) In the battery according to any one of (1) to (4), an annular restraining member for suppressing radial expansion of the electrode body is provided on each outer periphery of the plurality of electrode bodies. It is characterized by being inserted.
(6) In the battery according to any one of (1) to (5), the case and the lid constituting the exterior body are both made of a resin material.

(7) A method for producing a battery, characterized in that it includes steps from the following (electrode body forming step) to (sealing step).
* Electrode body forming step: Positive and negative bipolar plates are arranged opposite to each other with a separator interposed therebetween, and an electrode body is formed by performing winding while maintaining the arrangement state.
* Unit formation step: A positive electrode plate positioned on both end surfaces of the electrode body in the winding axis direction by inserting annular restraining members for suppressing radial expansion of the electrode body on the outer periphery of the electrode body A current collecting member having a protruding portion extending in the radial direction of the electrode body is joined to the negative electrode plate to form a cell unit.

* Storing step: For a case where a plurality of cell chambers are divided into a plurality of cell chambers by a plurality of partition walls, and each of the plurality of cell chambers has an opening, each of the plurality of cell units is separated by a winding shaft. One unit is stored in each cell room in a state of intersecting with.
* Connecting step: Joining each other's protrusions through the through holes provided in the partition wall adjacent to the protrusions between adjacent cell units housed in the case Connect in series.

* Electrolyte injection step: Electrolyte is injected into each cell chamber of the case.
* Sealing step: a lid provided with a gas flow path that enables gas flow between the cell chambers of the case, and a safety valve that is opened and closed by internal pressure connected to the gas flow path Are arranged facing each other so as to seal the opening of the case, and are joined to each other.

  The battery according to the present invention is in a state in which the electrode bodies are divided into cell chambers in the exterior body, and since they are connected in series with each other, the plurality of electrode bodies in the battery are separated from the battery by a large current. Even in the case of taking out, the electrical uniform state is maintained. That is, in the battery according to Patent Document 1, a plurality of electrode bodies are connected in parallel by current collector plates in one cell chamber, and input / output is performed from one end of the current collector plates. There has been a problem in that variations in the consumption of the electrolytic solution occur, and if the use is continued for a long time, the output variation of the battery becomes remarkable and the life is shortened.

  On the other hand, in the battery according to the present invention, a plurality of electrode bodies are stored in the exterior body separately for each cell chamber, and are connected in series with each other. Only one will be connected. Therefore, in the battery according to the present invention, even when a large current is taken out from the battery, the current flowing through each of the plurality of electrode bodies is uniform, and even when the battery is used for a long time for a large current application, Output variation is kept small and battery life is long.

Therefore, the battery according to the present invention has an advantage that high reliability can be maintained over a long period of time even for applications requiring a large current output.
In the battery according to the present invention, as shown in (2) above, if a gas flow path that allows gas flow between a plurality of cell chambers is provided, there is capacity variation between the electrode bodies. Also, the uniformity of the internal pressure among the plurality of cell chambers in the battery is maintained through the gas flow path. Thereby, in the battery according to (2), the progress of electrode plate deterioration due to oxidation is suppressed, and the life is longer.

  Moreover, the battery manufacturing method according to the present invention can easily manufacture a battery having the above advantages.

The best mode for carrying out the present invention will be described with a nickel-hydrogen (Ni-MH) sealed secondary battery (hereinafter simply referred to as “battery”) 1 as an example with reference to the drawings. The battery 1 is for HEV and has a voltage of 7.2 (V) and a nominal capacity of 6500 (mAh). The battery 1 described below is merely an example of the present invention and does not limit the present invention.
(Configuration of battery 1)
First, the structure of the battery 1 is demonstrated using FIG. 1 and FIG.

  As shown in FIG. 1A, the battery 1 according to the present embodiment has an exterior body formed of a case 10 and a lid 11 whose longitudinal direction is the X direction. Both the case 10 and the lid 11 are made of a synthetic resin material, and the openings are welded together to keep the inside sealed. A rib 10 </ b> R extending in the Z direction is formed on a part (XZ surface) of the outer surface of the case 10 which is one component of the exterior body. The rib 10R is obtained by processing a part of the case 10 made of a synthetic resin material into a beam shape. The functions performed by the ribs 10R include securing a refrigerant passage between the batteries 1 when a plurality of batteries 1 are arranged adjacent to each other, and improving the rigidity of the outer surface of the case 10. .

In addition, external connection terminals 13 a and 13 b are attached to both end surfaces of the case 10 in the X direction. Of the two external connection terminals 13a and 13b, the terminal 13b is not shown for convenience.
A safety valve 12 for releasing the internal gas to the outside when the internal pressure reaches a specified value is attached to the upper surface of the lid 11 in the Z direction.

  As shown in FIG. 1B, the battery 1 has six electrode body units 17 in the internal space formed by the case 10 and the lid 11. Each electrode body unit 17 includes a spiral electrode body 14, positive and negative current collecting plates 15 a and 15 b bonded to both ends of the winding axis direction, and a restraining band 16 that is fitted on the outer periphery of the electrode body 14. It consists of and. Of these, each of the positive and negative current collecting plates 15a and 15b is subjected to burring processing at the joint portion with the electrode body 14, and tab portions 15a2 and 15b2 extending in a tongue shape in the Z direction (FIG. 3B). )), The junction 15p is formed.

  The restraining band 16 is formed in a ring shape using a metal material (for example, SPCD plated with Ni), and has an inner peripheral diameter substantially equal to the outer periphery of the electrode body 14. Yes. Here, a separator 143 (not shown in FIG. 1) is arranged on the outermost periphery of the electrode body 14 to which the restraining band 16 is fitted, and insulation is provided between the restraining band 16 made of a metal material. It is ensured, and an internal short circuit or the like does not occur in the electrode body 14.

  The case 10 is divided into six cell chambers 102 by a partition wall 101, and has a through-hole 101h for connection at an upper portion of each partition wall 101 in the Z direction. The size of each cell chamber 102 in the case 10 is set to be approximately equal to the size in the same direction of the electrode body unit 17 in the X direction and the Y direction. In the Z direction, the length in the Z direction of the current collector plates 15a and 15b is determined. It is set slightly larger. Further, as described above, the external connection terminals 13a and 13b are provided on the side surfaces of the case 10 on both sides in the X direction. The terminals 13a and 13b are accommodated in the cell chambers 102 located at both ends in the X direction. A part of each electrode body unit 17 is exposed in the cell chamber 102 so as to be connected to the current collector plates 15a and 15b.

In the above description, the size of the electrode body unit 17 in the X direction and the Y direction is substantially equal to the size of the cell chamber 102, which means that the electrode body unit 17 can be stored in the cell chamber 102 without causing a large gap. It is.
With respect to the case 10 having such a configuration, the six electrode body units 17 are each divided and housed in each cell chamber 102, and one electrode body unit 17 is provided between the adjacent electrode body units 17. The positive electrode current collector plate 15 a and the negative electrode current collector plate 15 b of the other electrode body unit 17 are joined by welding through a through hole 101 h provided in the partition wall 101. That is, as shown in FIG. 1B, each of the six electrode body units 17 is housed in each cell chamber 102 and connected in series.

For the lid 11, a partition wall 111 is formed corresponding to the partition wall 101 provided in the case 10. And the notch part 111a is formed in the partition wall 111 in this lid | cover 11 in the one part area | region.
Although not shown in FIG. 1 and the like, a predetermined amount of electrolytic solution is injected into each cell chamber 102. The injection amount of the electrolytic solution is an amount sufficient for charging and discharging each electrode body unit 17 and is set to an amount that does not reach the notch portion 111a of the lid 11 only by tilting the battery 1 several times. Yes.
(Function of the notch 111a provided in the lid 11)
Next, as described above, each partition wall 111 of the lid 11 in the battery 1 is provided with the notch 111a. The function performed by this will be described with reference to FIG. FIG. 2 is a cross-sectional view showing a main part of the battery 1.

As shown in FIG. 2, in the battery 1 according to the present embodiment, each of the six electrode body units 17 is stored separately for each cell chamber 102. In the case 10, the cell chambers 102 are in an independent state.
The notch 111 a provided in the partition wall 111 in the lid 11 has a function as a gas flow path that enables gas flow between the cell chambers 102. That is, when the battery 1 is used, gas is generated from the electrode body 14. When gas is generated in this way, if the cell chamber 102 is formed completely separately and independently as in the above-mentioned Patent Document 1, the amount of gas generated due to capacity variation of each electrode body 14 also varies. Will occur. On the other hand, in the battery 1 according to the present embodiment, this gas can be smoothly circulated between the cell chambers 102 by providing the notch portions 111 a in each of the partition walls 111 in the lid 11.

  Further, in the battery 1, the number of the safety valves 12 can be reduced to one by providing the notches 111 a as described above. Here, the safety valve 12 uses a lid 11 as a part of the constituent elements (this part is referred to as a valve part 112), and an internal space formed by this and the cap 121 of the safety valve 12 is made of rubber. The valve body 122 is accommodated. An opening 11 h is provided in the valve portion 112 of the lid 11 so as to allow the cell chamber 102 to pass through the portion in which the valve body 122 is accommodated. In a state where the internal pressure of the battery 1 is not more than a specified value, that is, in a normal state, the opening 11h is closed with the valve body 122.

Since the notch 111a in the lid 11 enables gas flow in the six cell chambers 102, the internal pressure of the entire battery 1 can be adjusted with one safety valve 12 as described above.
(Superiority of battery 1)
The superiority of the battery 1 having the above structure is as follows.
(1) As shown in FIG. 1, in the battery 1, the six electrode body units 17 are housed in the cell chambers 102 that are separated, and are connected in series. For this reason, in the battery 1, the electrical uniform state between the electrode body units 17 is maintained even when a large current is taken out. In other words, since the battery of Patent Document 1 contains a plurality of electrode bodies connected in parallel in one cell chamber, the current flowing when a large current is taken out varies between the electrode bodies. . As a result, conventional batteries have problems such as variations in battery output and short life.

On the other hand, since the battery 1 according to the present embodiment has the structure shown in FIG. 1, even when a large current is taken out, a uniform current flows through the six electrode bodies 14. Therefore, the battery 1 can maintain high reliability over a long period even for applications that require a large current output.
(2) Moreover, in the battery 1 according to the present embodiment, since the gas flow path that enables gas flow between the six cell chambers 102 is provided, the internal pressure is uniformly maintained as the battery 1 as a whole. There is also an advantage that the progress of deterioration of the electrode plate due to the above is suppressed. Here, in the case where each cell chamber is formed in a completely independent state as in the battery of Patent Document 1, the internal pressure between the cell chambers is increased due to the capacity variation of the electrode body accommodated in each cell chamber. Variations occur, and the progress of deterioration due to oxidation of the electrode plate varies, resulting in a short life when viewed as a whole battery.

On the other hand, in the battery 1 according to the present embodiment, gas can flow between the cell chambers 102 by the cutout portions 111a of the lid 11, and the internal pressures of the six cell chambers 102 are uniformly maintained. . Therefore, it can be said that the battery 1 has a long life because the progress of oxidation deterioration of the electrode plate as a whole is suppressed.
(Method for manufacturing battery 1)
Next, steps from the production of the electrode body unit 17 that is characteristic to the series connection of the electrode body unit 17 in the manufacturing method of the battery 1 will be described with reference to FIGS. 3 and 4.

As shown in FIG. 4A, an annular restraining band 16 is fitted on the outer periphery of a spiral electrode body 14 prepared in advance. The spiral electrode body 14 is formed by arranging the positive electrode plate 141 and the negative electrode plate 142 so as to face each other with the separator 143 interposed therebetween, and winding the electrode plate in this state.
On the positive electrode plate 141 of the spiral electrode body 14, for example, a nickel sintered porous body is formed on the surface of an electrode plate core made of punching metal, and then an active material mainly composed of nickel hydroxide is formed by nickel impregnation by a chemical impregnation method. It is produced by filling a sintered porous body.

  The negative electrode plate 142 is obtained, for example, by filling the surface of an electrode plate core made of punching metal with a paste-like negative electrode active material made of a hydrogen storage alloy, and rolling it to a predetermined thickness after drying. is there. In addition, about the manufacturing method of these positive / negative bipolar plates 141 and 142 and the separator 143, it is the same as that of the past, and you may use methods other than the above.

In addition, the positive electrode plate 141 on one side and the negative electrode plate 142 on the other side are slightly exposed at both ends of the spiral electrode body 14 in the winding axis direction, that is, in the X direction.
As shown in FIG. 3A, since the electrolyte solution is not contained in the electrode body 14 when the restraint band 16 is fitted on the outer periphery of the electrode body 14, the outer diameter of the electrode body 14 is set to the restraint band 16. Thus, the restraining band 16 can be easily fitted on the electrode body 14 without any special operation.

  Next, as shown in FIG. 3 (b), the positive electrode current collector plate 15a and the negative electrode current collector plate 15b are joined to both ends in the X direction with respect to the electrode body 14 to which the restraining band 16 is fitted. These current collector plates 15a and 15b are both composed of joint portions 15a1 and 15b1 to the electrode body 14 and tab portions 15a2 and 15b2 extending upward in the Z direction. As shown, joint portions 15p are formed in both tab portions 15a2 and 15b2 in a recessed shape. Further, as shown in the upper enlarged portion of FIG. 3B, the current collector plates 15a and 15b are formed with burring portions 15W for reliable bonding to the respective electrode plates 141 and 142.

In addition, in joining the current collecting plates 15a and 15b to the electrode body 14, a laser welding method or the like can be used in addition to the resistance welding method.
Next, as shown in FIG. 4A, one electrode body unit 17 is accommodated for each cell chamber 102 formed in the case 10. The size relationship between the electrode body unit 17 and the cell chamber 102 is such that the length of each electrode body unit 17 (distance from the surface of the current collector plate 15a to the current collector plate 15b) is substantially the same as the size of the cell chamber 102 in the X direction. They are set the same. Further, the depth in the Z direction in the internal space of each cell chamber 102 of the case 10 is such that when the electrode body unit 17 is accommodated in the cell chamber 102, the junction 15p of each current collector plate 15a, 15b is exactly divided by each partition. The wall 101 is set so as to correspond to a portion where the through hole 101h is formed.

Finally, as shown in FIG. 4 (b), the current collector plates 15a and 15b facing each other with the partition wall 101 sandwiched between the case 10 in a state where the electrode body unit 17 is housed in each cell chamber 102 are joined. The parts 15p are resistance welded and joined by flowing current while pressing the parts 15p with the electrodes 501 and 502 for resistance welding.
As described above, the process up to storing the electrode body unit 17 in the case 10 is completed.

In addition, after inject | pouring a required quantity electrolyte solution into each cell chamber 102 of case 10 after this, it seals with the lid | cover 11, However, description of these each process is abbreviate | omitted.
(Confirmation experiment)
Below, the experiment conducted in order to confirm the said superiority of the battery 1 which concerns on this Embodiment is demonstrated using FIG. In FIG. 5, (a) shows an electrode body unit 17 built in the battery according to Example 1, (b) shows an electrode body unit 18 built in the battery according to Example 2, and (c) relates to a comparative example. The typical side view of the electrode body unit 217 incorporated in a battery is shown. The three types of electrode body units 17, 18, 217 are set so as to have the same electrode plate facing area. Each battery was set to a voltage of 7.2 (V) and a nominal capacity of 6500 (mAh).

(Example 1)
As shown in FIG. 5 (a), the electrode body unit 17 included in the battery according to Example 1 has the same configuration as that included in the battery 1 in the above embodiment, and has the following dimensions. Have.
1. Positive electrode plate: sintered nickel positive electrode plate, electrode plate length 720 (mm), electrode plate width 50 (mm), electrode plate thickness 0.4 (mm)
2. Negative electrode plate: hydrogen storage alloy negative electrode plate, electrode plate length 800 (mm), electrode plate width 50 (mm), electrode plate thickness 0.2 (mm)
3. Electrode body 14; spiral electrode body, winding outer diameter φ31 (mm)
4). Current collecting plates 15a and 15b: Z direction total height 45 (mm), distance 40.5 (mm) from lower end of Z direction to center of joint 15p
5). Restraint band: SPCD with Ni plating, X direction width 40 (mm)
(Example 2)
As shown in FIG.5 (b), the electrode body unit 18 with which the battery which concerns on Example 2 is provided has the structure which eliminated the restraint band 16 from the electrode body unit 17 which concerns on the said Example 1, and is in another structure. There is no difference.

(Comparative example)
As shown in FIG.5 (c), the electrode body unit 217 with which the battery which concerns on a comparative example is equipped has the four electrode bodies 214 connected in parallel, and has the following dimensions.
1. Each electrode body 214; spiral electrode body, winding outer diameter φ15 (mm)
2. Gap between electrode bodies 214; 3 (mm)
3. Current collecting plates 215a and 215b; total height in the Z direction 85 (mm), distance from the lower end in the Z direction to the center of the joint 215p 80.5 (mm)
Note that the electrode body unit 217 according to the comparative example has the same electrode plate facing area as the electrode body units 17 and 18 as a whole as described above. In addition, other components in the batteries of Examples 1 and 2 and the comparative example were the same as those in the above embodiment.

(Experiment 1) High-temperature pulse cycle life For the three types of batteries of Examples 1 and 2 and Comparative Example, first, charging was performed under the following conditions.
Charging conditions: In an atmosphere at a temperature of 25 (° C.), the charging current was 6500 (mA) until the battery capacity reached 50%.

  Energizing condition: 40 (A) discharge ⇒ 40 (A) charge ⇒ 80 (A) discharge ⇒ 80 (A) charge ⇒ 120 (A) discharge ⇒ 120 (A) charge ⇒ 160 (A) discharge ⇒ 160 (A) charge Was conducted with a 10 (min.) Rest period between them, and energized for 10 (sec.) After 10 (min.) Rest after each discharge. And each battery voltage in 10 (sec.) Progress time was measured for every discharge current. The obtained battery voltage value was plotted against each discharge current, and the slope was determined as the battery resistance R1 of each battery in the initial stage.

Next, each battery was subjected to a high temperature pulse cycle under the following conditions.
High-temperature pulse cycle condition: 50 (A) while controlling charging so that SOC (State of Charge: charging condition) is maintained within a range of less than 100 (%) in an atmosphere at a temperature of 45 (° C.) Intermittent charging / discharging was repeated 20000 (cycles) with current.

And about each battery after repeating a cycle, battery resistance R2 was computed with the method similar to calculation of the said battery resistance R1. Table 1 shows the ratio of the battery resistances R1 and R2.
(Experiment 2) Battery Output For the three types of batteries of Examples 1 and 2 and Comparative Example, charging was performed at 1 (It) and 1 (Hr.), 15 (It), and final voltage 1.0 (V). The battery output calculated by discharging was measured. The output of the battery according to the comparative example is expressed as an index with “100”, and is shown in Table 1.

表１に示すように、電池抵抗比（Ｒ２／Ｒ１）は、実施例１の電池が０．９２、実施例２の電池が０．９１であったのに対して、比較例の電池では０．７５と０．２ポイント以上劣る結果となった。また、電池出力の比についても、比較例に係る電池に対して実施例１に係る電池が３２ポイント優れ、実施例２に係る電池が３０ポイント優れる結果となった。

As shown in Table 1, the battery resistance ratio (R2 / R1) was 0.92 for the battery of Example 1 and 0.91 for the battery of Example 2, whereas it was 0 for the battery of the comparative example. .75, which was inferior to 0.2 points or more. Moreover, regarding the battery output ratio, the battery according to Example 1 was superior by 32 points and the battery according to Example 2 was superior by 30 points with respect to the battery according to the comparative example.

In the electrode unit 217 according to the comparative example, the four electrode bodies 214 are connected in parallel with being sandwiched between the two current collector plates 215, and the current flowing through the electrode body 214 in the upper and lower directions in the Z direction. It is considered that the high temperature pulse cycle life is shortened due to the difference in.
On the other hand, in the batteries according to Example 1 and Example 2, the electrode body units 17 and 18 are constituted by one electrode body 14, and the electrode pair 14 is formed like the electrode body unit 217 according to the comparative example. This is probably because non-uniformity of the current flowing between them did not occur.

Further, when comparing the battery according to Example 1 and the battery according to Example 2, the battery according to Example 1 has an excellent battery resistance ratio (R2 / R1) of 0.01 points and a battery output ratio of 2. The point was excellent. This occurs because the restraint band 16 is fitted around the outer periphery of the electrode body 14 according to the first embodiment, whereas the electrode body unit 18 according to the second embodiment does not use the restraint band. It is thought that That is, it can be seen that the restraining band 16 provided in the electrode body unit 17 according to the first embodiment has an effect of suppressing the expansion of the electrode plate during charging and discharging. For this reason, it is considered that the battery including the electrode body unit 17 according to Example 1 in which the expansion of the electrode plate is small has obtained excellent results in both the battery resistance ratio and the battery output ratio.
(Other matters)
The above embodiment is an example of the present invention, and the present invention is not limited to the above embodiment. For example, in the above embodiment, the Ni-MH battery is taken as an example. However, the type of battery is not limited to this as long as it is an alkaline sealed secondary battery, such as a Ni-Cd battery or a Li battery. It can also be applied.

Moreover, in the said embodiment, although the battery 1 provided with the six electrode body units 17 inside was used, the accommodation number etc. of the electrode body unit 17 are not limited to this. For example, the number of built-in electrode body units 17 may be 5 units or less, and conversely, it may be 7 units or more.
Further, in the above embodiment, the gas flow path between the cell chambers 102 is secured by the notch portions 111 a provided in the partition walls 111 of the lid 11. However, the present invention is not limited thereto. For example, in FIG. 1A, a configuration in which a pipe that connects the cell chambers 102 may be provided above the lid 11 in the Z direction.

  Furthermore, in the present invention, the materials of the electrode plates 141 and 142 and the material of the restraining band 16 employed in the battery 1 according to the above embodiment can be changed as appropriate. However, as a material used for the configuration of the restraint band 16, it is desirable to use a material whose elongation per unit area is at least smaller than the material forming the case 10.

  The present invention is particularly useful for realizing an alkaline sealed secondary battery that requires a large current output, such as a HEV battery.

(A) is the external appearance perspective view of the battery 1 which concerns on embodiment, (b) is an expansion | deployment perspective view which shows the state which open | released the cover 11 of the battery 1. FIG. 2 is a cross-sectional view of a main part of the battery 1. (A) is process drawing which shows the insertion process of the restraint band 16 to the outer peripheral part of the electrode body 14, (b) shows the joining process of the current collecting plates 15a and 15b to the both ends of the electrode body 14. It is process drawing. (A) is process drawing which shows the accommodation process of the electrode body 14 to each cell chamber 102 of the battery case 10, (b) is the joining process of the current collector plates 15a and 15b of the adjacent electrode body 14 between. FIG. (A) is a side view of the electrode body unit 17 which concerns on Example 1, (b) is a side view of the electrode body unit 18 which concerns on Example 2, (c) is an electrode which concerns on a comparative example. 4 is a side view of a body unit 217. FIG.

Explanation of symbols

1. Alkaline sealed secondary battery 10. Case 11. Lid 12. Safety valves 13a, 13b. External connection terminal 14. Electrode bodies 15a, 15b. Current collecting plate 16. Restraint band 17. Electrode body unit 101. Partition wall 101h. Through hole 102. Cell chamber 111a. Cutout portion 141. Positive plate 142. Negative electrode plate 143. Separator

Claims (7)

A positive and negative bipolar plate having a plurality of electrode bodies wound in a state of being opposed to each other with a separator interposed therebetween, and an alkaline sealed secondary battery having an exterior body that houses the plurality of electrode bodies,
The region for storing the plurality of electrode bodies in the exterior body is divided into a plurality of cell chambers according to the number of storage of the electrode bodies with an insulating partition wall,
Each of the plurality of electrode bodies is housed separately for each cell chamber in a state in which a winding shaft intersects the partition wall, and is connected in series with each other. battery. The exterior body is composed of a case and a lid,
2. The alkali sealed secondary according to claim 1, wherein at least one of the case and the lid is provided with a gas flow path that enables gas flow between the plurality of cell chambers. battery. In each of the plurality of electrode bodies, a current collecting member having a protruding portion extending in the radial direction of the electrode body is joined to the positive electrode plate and the negative electrode plate located on both end surfaces in the winding axis direction. ,
The partition wall in the exterior body has a through hole formed in a portion where the vicinity of the end of the protruding portion is close when the electrode body is stored in each cell chamber,
The adjacent electrode bodies are connected in series by joining the projecting portions of the current collecting members positioned across the partition wall through the through holes. 2. The alkaline sealed secondary battery according to 2. The partition wall has a form corresponding to each other, and is formed in both the case and the lid,
The gas flow path is formed by cutting out a part of the partition wall of the lid,
The lid body is provided with a safety valve connected to the gas flow path for releasing the internal gas to the outside when the pressure inside the exterior body exceeds a predetermined pressure. The alkaline sealed secondary battery according to claim 2 or 3, characterized in that 5. An annular restraining member for suppressing radial expansion of the electrode body is inserted into the outer periphery of each of the plurality of electrode bodies. Alkaline sealed secondary battery. The alkaline sealed secondary battery according to any one of claims 1 to 5, wherein the exterior body is made of a resin material. An electrode body forming step in which the positive and negative bipolar plates are disposed opposite to each other with the separator interposed therebetween, and the electrode body is formed by performing a winding process while maintaining the arrangement state;
A positive electrode plate and a negative electrode plate, which are fitted on the outer periphery of the electrode body, are fitted with annular restraining members for suppressing radial expansion of the electrode body, and are located on both end faces of the electrode body in the winding axis direction. A unit forming step of forming a cell unit by joining current collecting members each having a protruding portion extending in the radial direction of the electrode body;
The cell unit is divided into a plurality of cell chambers by a plurality of partition walls, and the plurality of cell chambers each have an opening, and the cell unit is placed in a state where the winding shaft intersects the partition wall. A storage step for storing one unit per cell room;
The plurality of cell units are joined to each other through the through holes provided in the partition wall adjacent to the protrusions between adjacent cell units accommodated in the case. A connection step to connect in series;
An electrolyte injection step of injecting an electrolyte into each cell chamber of the case;
A lid provided with a gas flow path that enables gas flow between the cell chambers of the case, and a safety valve that opens and closes by internal pressure is connected to the gas flow path; A method for producing an alkaline sealed secondary battery, comprising: a sealing step of sealing the opening of the case by placing it on the opening of the case and bonding the two together.

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