Battery

Abstract

A battery (1) comprises: a positive electrode (3) including manganese dioxide and graphite; a negative electrode (5) containing zinc; an electrolyte in which the positive electrode (3) and the negative electrode (5) are immersed; and polyethyleneimine ethoxylate contained in the negative electrode (5) or in the electrolyte.

Description

[Technical field]

[0001] The technology of the present disclosure relates to batteries. [Background technology]

[0002] Alkaline dry batteries with surfactants added to the negative electrode are known (Patent Documents 1 and 2). Such alkaline dry batteries can suppress hydrogen gas generation to prevent leakage and improve heavy load discharge performance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-069097 A [Patent Document 2] JP 2019-160786 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when a surfactant is added to the negative electrode of an alkaline dry battery, the medium load discharge performance may be degraded.

[0005] The disclosed technology has been made in consideration of the above points, and has an object to provide a battery that improves discharge performance under medium load. [Means for solving the problem]

[0006] A battery according to one embodiment of the present disclosure includes a positive electrode containing manganese dioxide and graphite, a negative electrode containing zinc and an electrolyte, the electrolyte in which the positive electrode and a separator are immersed, and polyethyleneimine ethoxylate contained in the negative electrode. Effect of the Invention

[0007] The disclosed batteries can provide improved discharge performance. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective cross-sectional view showing a battery according to an embodiment. [Diagram 2] FIG. 2 is a flow chart showing a battery manufacturing method for manufacturing a battery. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a battery according to an embodiment disclosed in the present application will be described with reference to the drawings. Note that the following description does not limit the technology of the present disclosure. In addition, in the following description, the same components are given the same reference numerals, and duplicated descriptions will be omitted.

[0010] [Battery 1 of the embodiment] The battery 1 of the embodiment is an alkaline dry battery, and includes a battery case 2, a positive electrode 3, a negative electrode 5, a current collector 6, and a separator 7, as shown in FIG. 1. FIG. 1 is a perspective cross-sectional view showing the battery 1 of the embodiment. The battery case 2 includes a positive electrode can 11, a negative electrode terminal plate 12, and a sealing gasket 14. The positive electrode can 11 is formed of a conductor, such as a metal. The positive electrode can 11 is formed in a bottomed cylindrical shape, and includes a side portion 15 and a bottom portion 16. The side portion 15 is formed of a bent plate so as to fit along the side surface of the cylinder. The bottom portion 16 is disposed so as to fit along one bottom surface of the cylinder. The bottom portion 16 is integrally connected to the side portion 15 so that an edge of the bottom portion 16 is adjacent to one end of the side portion 15.

[0011] Bottom portion 16 has projections and recesses, and a positive electrode terminal portion 17 is formed in the center of bottom portion 16. Positive electrode terminal portion 17 is formed so as to protrude from the inside of positive electrode can 11 toward the outside. Positive electrode can 11 has an opening 18. Opening 18 is formed in a portion of side portion 15 that corresponds to the other bottom surface of the cylinder. The inside of positive electrode can 11 is connected to the outside of positive electrode can 11 via opening 18.

[0012] The negative electrode terminal plate 12 is made of a conductor such as a metal and is formed in a generally disk shape. The negative electrode terminal plate 12 is arranged along the other bottom surface of the cylinder. Inside the battery case 2, an internal space 23 surrounded by the positive electrode can 11 and the negative electrode terminal plate 12 is formed by the negative electrode terminal plate 12 being arranged along the other bottom surface of the cylinder.

[0013] The sealing gasket 14 is formed of an insulator such as a resin, and is formed in a generally ring-like shape. The sealing gasket 14 surrounds the edge of the negative electrode terminal plate 12 and is disposed in the opening 18 of the positive electrode can 11. The sealing gasket 14 is sandwiched between the edge of the negative electrode terminal plate 12 and the positive electrode can 11, and closes the gap formed between the edge of the negative electrode terminal plate 12 and the positive electrode can 11. The negative electrode terminal plate 12 is fixed to the positive electrode can 11 via the sealing gasket 14 by the sealing gasket 14 being sandwiched between the edge of the negative electrode terminal plate 12 and the positive electrode can 11. The negative electrode terminal plate 12 is electrically insulated from the positive electrode can 11 via the sealing gasket 14 by the sealing gasket 14 being sandwiched between the edge of the negative electrode terminal plate 12 and the positive electrode can 11.

[0014] The battery case 2 further includes an exterior label 19. The exterior label 19 is made of a heat shrinkable film. The heat shrinkable film is an insulator and shrinks when heated. The exterior label 19 covers the area of ​​the surface of the battery case 2 exposed to the outside, excluding the negative electrode terminal plate 12 and the positive electrode terminal portion 17.

[0015] The positive electrode 3 is formed from a positive electrode mixture, which contains a positive electrode active material, a binder, and an aqueous potassium hydroxide solution (electrolyte). The positive electrode active material is manganese dioxide (MnO 2 and graphite C. The binder contains, for example, a polymer compound, and bonds powders formed from the positive electrode active material to each other to form a solid. The positive electrode 3 is formed in a tubular shape and is disposed in the internal space 23 of the battery case 2. The positive electrode 3 is in close contact with the inner circumferential surface of the side portion 15 of the positive electrode can 11 so that the positive electrode active material is electrically connected to the positive electrode can 11.

[0016] The negative electrode 5 is formed from a negative electrode active material and is formed in a gel state. The negative electrode active material contains zinc powder, an aqueous potassium hydroxide solution (electrolyte), and sodium polyacrylate. The negative electrode 5 further contains polyethyleneimine ethoxylate. The negative electrode 5 is disposed inside the positive electrode 3 in the internal space 23 of the battery case 2. The zinc powder contained in the negative electrode active material may be replaced with zinc alloy powder formed from a zinc alloy containing zinc.

[0017] The current collecting rod 6 is made of a conductor and is formed in a rod shape. The current collecting rod 6 is disposed in the internal space 23 along the central axis of the cylinder along which the side portion 15 is disposed. The current collecting rod 6 is embedded in the negative electrode 5 so that the current collecting rod 6 is electrically connected to the zinc powder of the negative electrode 5. The current collecting rod 6 also penetrates the center of the sealing gasket 14. The current collecting rod 6 is further fixed to the negative electrode terminal plate 12 by joining one end of the current collecting rod 6 to the negative electrode terminal plate 12, and is electrically connected to the negative electrode terminal plate 12.

[0018] The separator 7 is made of an insulator such as vinylon or pulp. The separator 7 is formed in a bottomed hollow cylindrical shape, and includes a side portion 25 and a bottom portion 26. The side portion 25 is disposed between the positive electrode 3 and the negative electrode 5 in the internal space 23. The bottom portion 26 is disposed between the negative electrode 5 and the bottom portion 16 of the positive electrode can 11 in the internal space 23. The bottom portion 26 is integrally connected to one end of the side portion 25 so that the region in the internal space 23 where the negative electrode 5 is disposed is separated from the region in the internal space 23 where the positive electrode 3 and the positive electrode can 11 are disposed. The separator 7 is disposed in this manner to separate the positive electrode 3 from the negative electrode 5, and separate the negative electrode 5 from the positive electrode can 11. The negative electrode 5 is electrically insulated from the positive electrode 3 because the separator 7 separates the positive electrode 3 and the negative electrode 5, and is electrically insulated from the positive electrode can 11 because the separator 7 separates the negative electrode 5 and the positive electrode can 11.

[0019] The battery 1 further includes an electrolyte. The electrolyte is formed from an aqueous solution containing potassium hydroxide KOH. The electrolyte further contains polyethyleneimine ethoxylate. The ratio of the sum of the masses of polyethyleneimine ethoxylate contained in the negative electrode 5 and the electrolyte to the mass of zinc contained in the negative electrode 5 is 10 ppm or more and 10,000 ppm or less. The electrolyte is disposed in the internal space 23 so that the positive electrode 3 and the negative electrode 5 are immersed in the electrolyte, and permeates the separator 7 and the positive electrode 3.

[0020] 2 is a flowchart showing a battery manufacturing method for manufacturing the battery 1. In the battery manufacturing method, a positive electrode mixture is prepared, and a positive electrode can 11 is prepared. The positive electrode mixture is molded (step S1) to form a positive electrode 3. The positive electrode 3 is inserted into the positive electrode can 11 so that the positive electrode 3 fits into the positive electrode can 11, i.e., so that the outer peripheral surface of the positive electrode 3 contacts the inner peripheral surface of the positive electrode can 11 (step S2).

[0021] The battery manufacturing method further includes preparing a separator 7. The separator 7 is molded (step S3) into a bottomed, hollow cylindrical shape. After the positive electrode 3 is inserted inside the positive electrode can 11 and the separator 7 is formed into a bottomed, hollow cylindrical shape, the separator 7 is inserted inside the positive electrode 3 (step S4).

[0022] In the battery manufacturing method, an electrolyte is further prepared. The electrolyte is prepared as an aqueous solution in which potassium hydroxide KOH of a predetermined concentration is dissolved. A predetermined amount of polyethyleneimine ethoxylate is added to the electrolyte (step S5). The process of step S5 may be omitted when polyethyleneimine ethoxylate is added to the negative electrode 5. After the separator 7 is inserted inside the positive electrode 3, the electrolyte is injected inside the positive electrode 3 (step S6). By injecting the electrolyte inside the positive electrode 3, the electrolyte permeates the separator 7 and then the positive electrode 3.

[0023] In the battery manufacturing method, the negative electrode 5 is further prepared. The negative electrode 5 is prepared in a gel state by mixing a predetermined amount of zinc powder, a predetermined amount of electrolyte (potassium hydroxide aqueous solution), and a predetermined amount of sodium polyacrylate. A predetermined amount of polyethyleneimine ethoxylate is further added to the negative electrode 5 (step S7). Note that the process of step S7 may be omitted when polyethyleneimine ethoxylate is added to the electrolyte. After the electrolyte permeates the separator 7 and the positive electrode 3, a predetermined amount of electrolyte is injected into the inside of the separator 7 (step S8).

[0024] In the battery manufacturing method, a current collecting rod 6, a negative electrode terminal plate 12, and a sealing gasket 14 are further prepared. The current collecting rod 6 is joined to the negative electrode terminal plate 12 so that the current collecting rod 6 is in electrical contact with the negative electrode terminal plate 12, and the sealing gasket 14 is joined to the negative electrode terminal plate 12 so that the edge of the negative electrode terminal plate 12 is covered by the sealing gasket 14, thereby producing a sealing body. After the negative electrode 5 is injected, the sealing body is attached to the positive electrode can 11 so that the current collecting rod 6 joined to the negative electrode terminal plate 12 is embedded in the negative electrode 5, and the negative electrode terminal plate 12 and the sealing gasket 14 close the opening 18. After the sealing body is attached to the positive electrode can 11, a portion of the positive electrode can 11 near the opening 18 is crimped so that a gap formed between the negative electrode terminal plate 12 and the positive electrode can 11 is sealed by the sealing gasket 14 (step S9). When positive electrode can 11 is crimped, sealing gasket 14 is deformed, the sealing body is fixed to positive electrode can 11, and internal space 23 is sealed from the outside.

[0025] In the battery manufacturing method, further, an exterior label 19 is prepared. After the current collector 6, the negative electrode terminal plate 12, and the sealing gasket 14 are fixed to the positive electrode can 11, the exterior label 19 is wrapped around the battery case 2 so as to cover the area of ​​the surface of the battery case 2 excluding the negative electrode terminal plate 12 and the positive electrode terminal portion 17 (step S10). After the exterior label 19 is wrapped around the battery case 2, the exterior label 19 is heated, shrunk, and attached to the battery case 2, and the battery 1 is manufactured. According to such a battery manufacturing method, the battery 1 can be appropriately manufactured so that the polyethyleneimine ethoxylate is appropriately added to the negative electrode 5 or the electrolyte.

[0026] [Evaluation test of battery 1] In order to confirm the effect of the battery 1 of the embodiment, a number of battery samples were fabricated and a medium-load continuous discharge test was performed on each of the battery samples. Table 1 shows a number of fabrication conditions corresponding to the battery samples and a number of medium-load continuous discharge test results. [Table 1]

[0027] The multiple battery samples include a battery of Comparative Example 1, a battery of Comparative Example 2, a battery of Comparative Example 3, a battery of Example 1, a battery of Example 2, a battery of Example 3, a battery of Example 4, a battery of Example 5, and a battery of Example 6.

[0028] The battery samples are produced under different production conditions. The production conditions are indicated by the additive and the amount of additive. The additive indicates a surfactant added to the negative electrode 5 or the electrolyte, and indicates "polyethyleneimine ethoxylate", "sodium alkylbenzene sulfonate", "alcohol ethoxylate", or "none". That is, when the additive of a certain battery sample indicates "polyethyleneimine ethoxylate", it indicates that polyethyleneimine ethoxylate is added to the negative electrode 5 or the electrolyte of the battery sample. When the additive of a certain battery sample indicates "sodium alkylbenzene sulfonate", it indicates that sodium alkylbenzene sulfonate is added to the negative electrode 5 or the electrolyte of the battery sample, and polyethyleneimine ethoxylate is not added to the negative electrode 5 or the electrolyte of the battery sample. When the additive of a certain battery sample indicates "alcohol ethoxylate", it indicates that alcohol ethoxylate is added to the negative electrode 5 or the electrolyte of the battery sample, and polyethyleneimine ethoxylate is not added to the negative electrode 5 or the electrolyte of the battery sample. When the additives of a certain battery sample show "none," this indicates that surfactants such as polyethyleneimine ethoxylate, sodium alkylbenzene sulfonate, and alcohol ethoxylate have not been added to the negative electrode 5 and electrolyte of that battery sample.

[0029] The additive amount of a certain battery sample indicates the total amount of surfactant added to the negative electrode 5 and electrolyte of that battery sample, and indicates the ratio of the total amount of surfactant added to the negative electrode 5 and electrolyte of that battery sample to the mass of zinc contained in the negative electrode 5 of that battery sample. In other words, when the additive amount of a certain battery sample indicates "X ppm / Zn", it indicates that the mass of the surfactant added to the negative electrode 5 and electrolyte of that battery sample divided by the mass of zinc contained in the negative electrode 5 of that battery sample multiplied by one million is equal to the value of X.

[0030] The battery samples were produced in the same manner except for the different production conditions, that is, the positive electrode 3, current collector 6, separator 7, positive electrode can 11, negative electrode terminal plate 12, and sealing gasket 14 were produced so that the battery size of the battery samples was LR14 (C battery).

[0031] The additive of the battery of Comparative Example 1 indicates "none." The additive amount of the battery of Comparative Example 1 indicates "0 ppm / Zn." That is, the battery of Comparative Example 1 is produced so that no surfactant is added to the negative electrode 5 and the electrolyte.

[0032] The additive of the battery of Comparative Example 2 is "sodium alkylbenzene sulfonate." The additive amount of the battery of Comparative Example 2 is "100 ppm / Zn." That is, the battery of Comparative Example 2 is produced such that 100 ppm of sodium alkylbenzene sulfonate is added to the negative electrode 5 and the electrolyte relative to the zinc contained in the negative electrode 5.

[0033] The additive of the battery of Comparative Example 3 is "alcohol ethoxylate". The additive amount of the battery of Comparative Example 3 is "100 ppm / Zn". That is, the battery of Comparative Example 3 is produced such that 100 ppm of alcohol ethoxylate is added to the negative electrode 5 and the electrolyte relative to the zinc contained in the negative electrode 5.

[0034] The additive of the battery of Example 1 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 1 is "5 ppm / Zn". That is, the battery of Example 1 is produced such that 5 ppm of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte relative to the zinc contained in the negative electrode 5.

[0035] The additive of the battery of Example 2 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 2 is "10 ppm / Zn". That is, the battery of Example 2 is produced such that 10 ppm of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte relative to the zinc contained in the negative electrode 5.

[0036] The additive of the battery of Example 3 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 3 is "100 ppm / Zn". That is, the battery of Example 3 is produced such that 100 ppm of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte relative to the zinc contained in the negative electrode 5.

[0037] The additive of the battery of Example 4 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 4 is "1000 ppm / Zn". That is, the battery of Example 4 is produced such that 1000 ppm of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte relative to the zinc contained in the negative electrode 5.

[0038] The additive of the battery of Example 5 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 5 is "10000 ppm / Zn". That is, the battery of Example 5 is produced such that 10000 ppm of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte relative to the zinc contained in the negative electrode 5.

[0039] The additive of the battery of Example 6 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 6 is "50000 ppm / Zn". That is, the battery of Example 1 is produced such that 50000 ppm of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte relative to the zinc contained in the negative electrode 5.

[0040] A medium-load continuous discharge test result corresponding to a certain battery sample among the multiple medium-load continuous discharge test results is derived by performing a medium-load continuous discharge test on the battery sample. In the medium-load continuous discharge test performed on a certain battery sample, the battery sample is electrically connected to a load of 3.9 Ω, and the medium-load continuous discharge time is derived. The medium-load continuous discharge time indicates the duration that the battery sample is discharged before the battery voltage of the battery sample becomes smaller than the end voltage of 0.8 V.

[0041] Among the multiple medium-load continuous discharge test results, a medium-load continuous discharge test result corresponding to a certain battery sample indicates a value obtained by dividing the average medium-load continuous discharge time of the battery sample by the average medium-load continuous discharge time of the battery of Comparative Example 1, and multiplying the result by 100. The average medium-load continuous discharge time of the battery sample indicates an average of multiple medium-load continuous discharge times derived for the multiple batteries fabricated as that battery sample. The multiple medium-load continuous discharge test results indicate that a battery sample corresponding to a medium-load continuous discharge test result showing a larger value has better medium-load discharge performance.

[0042] Among the results of the medium-load continuous discharge tests, the result of the medium-load continuous discharge test corresponding to the battery of Comparative Example 1 shows 100, the result of the medium-load continuous discharge test corresponding to the battery of Comparative Example 2 shows 95, and the result of the medium-load continuous discharge test corresponding to the battery of Comparative Example 3 shows 105. The results of the medium-load continuous discharge tests show that the results of the medium-load continuous discharge test of the batteries of Comparative Examples 2 and 3 are roughly equivalent to the results of the medium-load continuous discharge test of the battery of Comparative Example 1, and that the medium-load discharge performance of the batteries of Comparative Examples 2 and 3 is roughly equivalent to the medium-load discharge performance of the battery of Comparative Example 1. That is, the results of the medium-load continuous discharge tests show that even if a surfactant other than polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte of the battery, the medium-load discharge performance of the battery is not significantly improved compared to a battery in which no surfactant is added to the negative electrode 5 and the electrolyte.

[0043] Among the multiple medium-load continuous discharge test results, the medium-load continuous discharge test result corresponding to the battery of Example 1 is 105, the medium-load continuous discharge test result corresponding to the battery of Example 2 is 125, and the medium-load continuous discharge test result corresponding to the battery of Example 3 is 140. Among the multiple medium-load continuous discharge test results, the medium-load continuous discharge test result corresponding to the battery of Example 4 is 140, the medium-load continuous discharge test result corresponding to the battery of Example 5 is 130, and the medium-load continuous discharge test result corresponding to the battery of Example 6 is 100.

[0044] The results of multiple medium-load continuous discharge tests show that the medium-load continuous discharge test results of the batteries of Examples 1 to 6 are greater than the medium-load continuous discharge test results of the battery of Comparative Example 2, and that the medium-load discharge performance of the batteries of Examples 1 to 6 is better than the medium-load discharge performance of the battery of Comparative Example 2. In other words, the results of multiple medium-load continuous discharge tests show that the medium-load discharge performance of the battery in which polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte is better than the medium-load discharge performance of the battery in which sodium alkylbenzenesulfonate is added to the negative electrode 5 and the electrolyte.

[0045] The results of multiple medium-load continuous discharge tests show that the medium-load continuous discharge test results of the batteries of Examples 2 to 5 are greater than the medium-load continuous discharge test results of the battery of Comparative Example 3, and that the medium-load discharge performance of the batteries of Examples 2 to 5 is better than the medium-load discharge performance of the battery of Comparative Example 3. That is, the results of multiple medium-load continuous discharge tests show that the medium-load discharge performance of a battery in which the polyethyleneimine ethoxylate added to the negative electrode 5 and the electrolyte is 10 ppm / Zn or more and 10,000 ppm / Zn or less is better than the medium-load discharge performance of a battery in which alcohol ethoxylate is added to the negative electrode 5 and the electrolyte.

[0046] The results of multiple medium-load continuous discharge tests show that the medium-load continuous discharge test results of the batteries of Examples 1 to 5 are greater than the medium-load continuous discharge test results of the battery of Comparative Example 1, and that the medium-load discharge performance of the batteries of Examples 1 to 5 is better than the medium-load discharge performance of the battery of Comparative Example 1. That is, the results of multiple medium-load continuous discharge tests show that the medium-load discharge performance of a battery in which the polyethyleneimine ethoxylate added to the negative electrode 5 and the electrolyte is 5 ppm / Zn or more and 10,000 ppm / Zn or less is better than the medium-load discharge performance of a battery in which no surfactant is added to the negative electrode 5 and the electrolyte.

[0047] A number of medium-load continuous discharge test results show that the medium-load continuous discharge test results of the batteries of Examples 3 and 4 are greater than the medium-load continuous discharge test results of the batteries of Examples 1 and 2. A number of medium-load continuous discharge test results show that when the ratio of the mass of polyethyleneimine ethoxylate to the mass of zinc is less than 100 ppm / Zn, the medium-load discharge performance of the battery tends to decrease as the amount of polyethyleneimine ethoxylate decreases.

[0048] A number of medium-load continuous discharge test results show that the medium-load continuous discharge test results of the batteries of Examples 3 and 4 are greater than the medium-load continuous discharge test results of the batteries of Examples 5 and 6. A number of medium-load continuous discharge test results show that when the ratio of the mass of polyethyleneimine ethoxylate to the mass of zinc is greater than 1000 ppm / Zn, the medium-load discharge performance of the battery tends to decrease as the amount of polyethyleneimine ethoxylate increases.

[0049] A drop test is further performed on each of the battery samples to confirm the effect of the battery 1 of the embodiment. Table 2 shows the preparation conditions and the drop test results corresponding to the battery samples. [Table 2]

[0050] The battery samples include a battery of Comparative Example 4, a battery of Example 7, a battery of Example 8, a battery of Example 9, a battery of Example 10, a battery of Example 11, a battery of Example 12, a battery of Example 13, a battery of Example 14, a battery of Example 15, and a battery of Example 16. The battery samples are produced under different production conditions. The production conditions are indicated by the additive, the amount of additive, the average particle size of Na-PA, and the amount of Na-PA added. The additive of a certain battery sample indicates the surfactant added to the negative electrode 5 or the electrolyte of the battery sample, similar to the additive amount described in Table 1. The amount of additive of a certain battery sample indicates the amount of surfactant added to the negative electrode 5 or the electrolyte of the battery sample, similar to the additive amount described in Table 1.

[0051] The Na-PA average particle size of a certain battery sample indicates the average particle size of sodium polyacrylate contained in the negative electrode 5 of the battery sample. The Na-PA addition amount of a certain battery sample indicates the amount of sodium polyacrylate contained in the negative electrode 5 of the battery sample, and indicates the ratio of the mass of sodium polyacrylate added to the negative electrode 5 of the battery sample to the mass of the electrolyte (EL) contained in the negative electrode 5 of the battery sample. In other words, when the Na-PA addition amount of a certain battery sample indicates "Y% / EL", it indicates that the value obtained by dividing the mass of sodium polyacrylate added to the negative electrode 5 of the battery sample by the mass of the electrolyte contained in the negative electrode 5 of the battery sample and multiplying the value by 100 is equal to the value of Y.

[0052] The battery samples were produced in the same manner except for the different production conditions, that is, the positive electrode 3, current collector 6, separator 7, positive electrode can 11, negative electrode terminal plate 12, and sealing gasket 14 were produced so that the battery size of the battery samples was LR14 (C battery).

[0053] The additive of the battery of Comparative Example 4 indicates "none". The additive amount of the battery of Comparative Example 4 indicates "0 ppm / Zn". The average particle size of Na-PA of the battery of Comparative Example 4 indicates "120 μm". The additive amount of Na-PA of the battery of Comparative Example 4 indicates "1.0% / EL". That is, the battery of Comparative Example 4 is produced so that no surfactant is added to the negative electrode 5 and the electrolyte, and so that only 1.0% / EL of sodium polyacrylate having an average particle size of 120 μm is contained in the negative electrode 5.

[0054] The additive of the battery of Example 7 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 7 is "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 7 is "30 μm". The additive amount of Na-PA of the battery of Example 7 is "1.5% / EL". That is, the battery of Example 7 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and 1.5% / EL of sodium polyacrylate having an average particle size of 30 μm is contained in the negative electrode 5.

[0055] The additive of the battery of Example 8 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 8 is "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 8 is "50 μm". The additive amount of Na-PA of the battery of Example 8 is "1.5% / EL". That is, the battery of Example 8 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and 1.5% / EL of sodium polyacrylate having an average particle size of 50 μm is contained in the negative electrode 5.

[0056] The additive of the battery of Example 9 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 9 is "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 9 is "120 μm". The additive amount of Na-PA of the battery of Example 9 is "1.5% / EL". That is, the battery of Example 9 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and 1.5% / EL of sodium polyacrylate having an average particle size of 120 μm is contained in the negative electrode 5.

[0057] The additive of the battery of Example 10 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 10 is "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 10 is "300 μm". The additive amount of Na-PA of the battery of Example 10 is "1.5% / EL". That is, the battery of Example 10 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and 1.5% / EL of sodium polyacrylate having an average particle size of 300 μm is contained in the negative electrode 5.

[0058] The additive of the battery of Example 11 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 11 is "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 11 is "500 μm". The additive amount of Na-PA of the battery of Example 11 is "1.5% / EL". That is, the battery of Example 11 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and 1.5% / EL of sodium polyacrylate having an average particle size of 500 μm is contained in the negative electrode 5.

[0059] The additive of the battery of Example 12 indicates "polyethyleneimine ethoxylate". The additive amount of the battery of Example 12 indicates "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 12 indicates "120 μm". The additive amount of Na-PA of the battery of Example 12 indicates "0.7% / EL". That is, the battery of Example 12 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and 0.7% / EL of sodium polyacrylate having an average particle size of 120 μm is contained in the negative electrode 5.

[0060] The additive of the battery of Example 13 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 13 is "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 13 is "120 μm". The additive amount of Na-PA of the battery of Example 13 is "1.0% / EL". That is, the battery of Example 13 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and 1.0% / EL of sodium polyacrylate having an average particle size of 120 μm is contained in the negative electrode 5.

[0061] The additive of the battery of Example 14 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 14 is "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 14 is "120 μm". The additive amount of Na-PA of the battery of Example 14 is "1.5% / EL". That is, the battery of Example 14 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and 1.5% / EL of sodium polyacrylate having an average particle size of 120 μm is contained in the negative electrode 5.

[0062] The additive of the battery of Example 15 is "polyethyleneimine ethoxylate". The additive amount of the battery of Example 15 is "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 15 is "120 μm". The additive amount of Na-PA of the battery of Example 15 is "2.0% / EL". That is, the battery of Example 15 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and so that 2.0% / EL of sodium polyacrylate having an average particle size of 120 μm is contained in the negative electrode 5.

[0063] The additive of the battery of Example 16 indicates "polyethyleneimine ethoxylate". The additive amount of the battery of Example 16 indicates "100 ppm / Zn". The average particle size of Na-PA of the battery of Example 16 indicates "120 μm". The additive amount of Na-PA of the battery of Example 16 indicates "2.5% / EL". That is, the battery of Example 16 is produced so that 100 ppm / Zn of polyethyleneimine ethoxylate is added to the negative electrode 5 and the electrolyte, and so that 2.5% / EL of sodium polyacrylate having an average particle size of 120 μm is contained in the negative electrode 5.

[0064] A drop test result corresponding to a certain battery sample among the multiple drop test results is derived by performing a drop test on the battery sample. In the drop test performed on a certain battery sample, whether the battery sample is properly manufactured or not is confirmed, the battery sample is dropped from 30 cm above a desk, and the closing voltage before the drop and the closing voltage after the drop are derived. The closing voltage before the drop indicates the battery voltage of the battery sample when the battery sample is electrically connected to a load of 1Ω for 0.3 seconds before the battery sample is dropped on the desk. The closing voltage before the drop indicates the battery voltage of the battery sample when the battery sample is electrically connected to a load of 1Ω for 0.3 seconds after the battery sample is dropped on the desk. The drop test result corresponding to a certain battery sample among the multiple drop test results indicates a value obtained by subtracting the closing voltage after the drop from the closing voltage before the drop, or indicates "unmanufacturable". The multiple drop test results indicate that the battery sample corresponding to a drop test result showing a value closer to 0V has better resistance to shock and vibration. The battery samples corresponding to the drop test results showing "unpreparable" indicate that a defect occurred in the battery samples that was not properly prepared due to a cause originating from sodium polyacrylate.

[0065] Among the multiple drop test results, the drop test result corresponding to the battery of Comparative Example 4 indicates 0.00 V. In other words, the multiple drop test results indicate that the battery in which polyethyleneimine ethoxylate is not added to the negative electrode 5 or the electrolyte has good resistance to impact and vibration.

[0066] Of the multiple drop test results, the drop test result for the battery of Example 7 was 0.03V, the drop test result for the battery of Example 8 was 0.01V, the drop test result for the battery of Example 9 was 0.00V, the drop test result for the battery of Example 10 was 0.00V, and the drop test result for the battery of Example 11 was “Cannot be manufactured.”

[0067] The results of the drop test show that the batteries of Examples 7 to 10 were properly manufactured, and that the battery of Example 11 was not properly manufactured. That is, the results of the drop test show that the battery is properly manufactured when the negative electrode 5 contains sodium polyacrylate having an average particle size of 300 μm or less. The results of the drop test further show that the battery is not properly manufactured due to defects when the negative electrode 5 contains sodium polyacrylate having an average particle size of 500 μm or more. As an example of the defects, many gel-like particles not containing zinc powder are formed, and zinc powder is segregated in the negative electrode 5.

[0068] The drop test results show that the drop test result of the battery of Comparative Example 4 is closer to 0 V than the drop test results of the batteries of Examples 7 and 8. In other words, the drop test results show that the resistance to impact and vibration of a battery in which polyethyleneimine ethoxylate is added to the negative electrode 5 or the electrolyte may be worse than that of a battery in which polyethyleneimine ethoxylate is not added to the negative electrode 5 or the electrolyte.

[0069] The results of the drop tests show that the results of the drop tests of the batteries of Examples 8 to 10 are equivalent to the results of the drop test of the battery of Comparative Example 4. That is, the results of the drop tests show that the resistance to impact and vibration of the battery in which the negative electrode 5 contains sodium polyacrylate having an average particle size of 50 μm or more is equivalent to the resistance to impact and vibration of the battery in which the negative electrode 5 or the electrolyte does not contain polyethyleneimine ethoxylate.

[0070] The drop test results show that the drop test results of the batteries of Examples 8 to 10 are closer to 0 V than the drop test result of the battery of Example 7. That is, the drop test results show that the resistance to impact and vibration of the battery in which the negative electrode 5 contains sodium polyacrylate having an average particle size of 50 μm or more is better than that of the battery in which the negative electrode 5 contains sodium polyacrylate having an average particle size of 30 μm or less.

[0071] The drop test results show that the drop test results of the batteries of Examples 9 and 10 are closer to 0 V than the drop test results of the batteries of Examples 7 and 8. That is, the drop test results show that the resistance to impact and vibration of the battery in which the negative electrode 5 contains sodium polyacrylate having an average particle size of 120 μm or more is better than that of the battery in which the negative electrode 5 contains sodium polyacrylate having an average particle size of 50 μm or less.

[0072] Of the multiple drop test results, the drop test result for the battery of Example 12 was 0.04V, the drop test result for the battery of Example 13 was 0.01V, the drop test result for the battery of Example 14 was 0.00V, the drop test result for the battery of Example 15 was 0.00V, and the drop test result for the battery of Example 16 was “Cannot be manufactured.”

[0073] The results of the drop tests show that the batteries of Examples 12 to 15 were properly manufactured, and that the battery of Example 16 was not properly manufactured. That is, the results of the drop tests show that the battery was properly manufactured when the negative electrode 5 contained 2.0% or less sodium polyacrylate relative to the electrolyte of the negative electrode 5. The results of the drop tests further show that when the negative electrode 5 contained 2.5% or more sodium polyacrylate relative to the electrolyte of the negative electrode 5, a defect occurred and the battery was not properly manufactured. An example of the defect is that the negative electrode 5 became too hard and the negative electrode 5 could not be injected into the separator 7.

[0074] The drop test results show that the drop test result of the battery of Comparative Example 4 is closer to 0 V than the drop test results of the batteries of Examples 12 and 13. In other words, the drop test results show that the resistance to impact and vibration of a battery in which polyethyleneimine ethoxylate is added to the negative electrode 5 or the electrolyte may be worse than that of a battery in which polyethyleneimine ethoxylate is not added to the negative electrode 5 or the electrolyte.

[0075] The drop test results further show that the drop test results of the batteries of Examples 13 to 15 are equivalent to the drop test result of the battery of Comparative Example 4. That is, the drop test results show that the resistance to impact and vibration of the battery in which the amount of sodium polyacrylate added in the negative electrode 5 is 1.0% / EL or more is equivalent to the resistance to impact and vibration of the battery in which polyethyleneimine ethoxylate is not added to the negative electrode 5 or the electrolyte.

[0076] The drop test results show that the drop test results of the batteries of Examples 13 to 15 are closer to 0 V than the drop test result of the battery of Example 12. That is, the drop test results show that the resistance to impact and vibration of the batteries in which the amount of sodium polyacrylate added in the negative electrode 5 is 1.0% / EL or more is better than that of the batteries in which the amount of sodium polyacrylate added in the negative electrode 5 is 0.7% / EL or less.

[0077] The drop test results show that the drop test results of the batteries of Examples 14 and 15 are closer to 0 V than the drop test results of the batteries of Examples 12 and 13. That is, the drop test results show that the resistance to impact and vibration of the batteries in which the amount of sodium polyacrylate added to the negative electrode 5 is 1.5% / EL or more is better than that of the batteries in which the amount of sodium polyacrylate added to the negative electrode 5 is 1.0% / EL or less.

[0078] [Effects of Battery 1 of the Embodiment] The battery 1 of the embodiment includes a positive electrode 3 containing manganese dioxide and graphite, a negative electrode 5 containing zinc, an electrolyte in which the positive electrode 3 and the negative electrode 5 are immersed, and polyethyleneimine ethoxylate contained in the negative electrode 5. The battery 1 of the embodiment also includes a positive electrode 3 containing manganese dioxide and graphite, a negative electrode 5 containing zinc, an electrolyte in which the positive electrode 3 and the negative electrode 5 are immersed, and polyethyleneimine ethoxylate contained in the electrolyte. In this case, the battery 1 of the embodiment can improve the discharge performance at a medium load.

[0079] In the battery 1 of the above-described embodiment, polyethyleneimine ethoxylate is added to both the negative electrode 5 and the electrolyte, but polyethyleneimine ethoxylate may not be added to either the negative electrode 5 or the electrolyte. Even when polyethyleneimine ethoxylate is added to either the negative electrode 5 or the electrolyte, the battery 1 can improve the discharge performance under medium load.

[0080] The mass ratio of polyethyleneimine ethoxylate to the mass of zinc contained in the negative electrode 5 of the battery 1 of the embodiment is 10 ppm or more and 10000 ppm or less. In this case, the medium load discharge performance of the battery 1 of the embodiment is better than that of a battery having a ratio of less than 10 ppm and is better than that of a battery having a ratio of more than 10000 ppm.

[0081] The battery 1 of the embodiment further includes sodium polyacrylate contained in the negative electrode 5. The ratio of the mass of sodium polyacrylate to the mass of the electrolyte contained in the negative electrode 5 is 1.0% or more and 2.0% or less. In this case, the battery 1 of the embodiment has better resistance to shock and vibration than a battery in which the ratio is less than 1.0%. The battery 1 of the embodiment can be more appropriately manufactured than a battery in which the ratio is more than 2.0%.

[0082] The average particle size of the sodium polyacrylate contained in the negative electrode 5 of the battery 1 of the embodiment is 50 μm or more and 300 μm or less. In this case, the battery 1 of the embodiment has better resistance to shock and vibration than a battery whose average particle size is smaller than 50 μm. The battery 1 of the embodiment can be more appropriately manufactured than a battery whose average particle size is larger than 300 μm.

[0083] Incidentally, the negative electrode 5 of the battery 1 described above contains sodium polyacrylate, but may contain a gelling agent other than sodium polyacrylate. An example of the gelling agent is polyacrylic acid. Even if the negative electrode 5 contains a gelling agent other than sodium polyacrylate, the battery 1 can improve the discharge performance at a medium load by containing polyethyleneimine ethoxylate in the negative electrode 5 or the electrolyte.

[0084] Although the embodiments have been described above, the embodiments are not limited to the above. The above-described components include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the above-described components can be appropriately combined. Furthermore, at least one of various omissions, substitutions, and modifications of the components can be made without departing from the gist of the embodiments. [Explanation of symbols]

[0085] 1:Battery 3: Positive electrode 5: Negative electrode

Claims

1. a positive electrode containing manganese dioxide and graphite; a negative electrode containing zinc and an electrolyte; an electrolyte in which the positive electrode and the separator are immersed; Polyethyleneimine ethoxylate contained in the negative electrode and the electrolyte and a battery.

2. The ratio of the mass of the polyethyleneimine ethoxylate to the mass of the zinc is 10 ppm or more and 10,000 ppm or less.

10. The battery of claim 1.

3. The negative electrode further comprises sodium polyacrylate, The ratio of the mass of the sodium polyacrylate to the mass of the electrolyte contained in the negative electrode is 1.0% or more and 2.0% or less.

3. The battery of claim 2.

4. The negative electrode further comprises sodium polyacrylate, The average particle size of the sodium polyacrylate is 50 μm or more and 300 μm or less.

3. The battery of claim 2.

5. The negative electrode further comprises sodium polyacrylate, a ratio of the mass of the sodium polyacrylate to the mass of the electrolyte solution contained in the negative electrode is 1.0% or more and 2.0% or less; The average particle size of the sodium polyacrylate is 50 μm or more and 300 μm or less.

3. The battery of claim 2.

6. a positive electrode containing manganese dioxide and graphite; a negative electrode containing zinc and an electrolyte; an electrolyte in which the positive electrode and the separator are immersed; Polyethyleneimine ethoxylate contained in the negative electrode and a battery.

7. a positive electrode containing manganese dioxide and graphite; a negative electrode containing zinc and an electrolyte; an electrolyte in which the positive electrode and the separator are immersed; Polyethyleneimine ethoxylate contained in the electrolyte and a battery.

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