TWI487166B - Primary aluminum-air battery - Google Patents

Description

Primary aluminum air battery

This invention relates to a disposable dry battery, and more particularly to an aluminum air battery.

The aluminum air battery is a battery that generates electricity by using aluminum metal as a fuel and air. The anode is aluminum metal, and the cathode is a composite material of porous carbon powder and carbon fiber. Aluminum and carbon materials are very light, and the reactants of the cathode are directly obtained from air, so the energy density is high, and the theoretical discharge value can be calculated to be more than 8,000 Wh/kg.

The chemical reaction equation of the aluminum electrode in an alkaline solution is shown by the discharge reaction of the following formula (1) and the hydrogen production reaction of the following formula (2).

Al+4OH ^- → Al(OH) ₄ ^- +3e ^- ; E=2.35V vs. SHE (1)

2Al+6H ₂ O → 2Al(OH) ₃ +3H ₂ (2)

From the current literature, the actual energy density of aluminum air batteries has exceeded 300Wh/kg, which is several times larger than commercial lead-acid batteries or nickel-metal hydride batteries. In addition, aluminum metal materials are only 1/7 of the price of nickel metal materials, and the material cost in mass production is relatively low in the future. The consumption and recycling of aluminum metal is not a commercial obstacle. The main component of the battery after power generation is aluminum hydroxide or aluminum oxide, which can be recycled and reused. Since aluminum hydroxide or aluminum oxide is a mineral in nature, Therefore, even if it directly abandons the environmental ecology, it is a battery with high environmental affinity.

Since the aluminum air battery has the above advantages, it has been used as a Battery use. Traditional disposable dry batteries have high application value in both emergency lighting and emergency power supply of portable electronic products, and have also established a huge market scale. However, in some specific storage environments (40 ° C ~ 70 ° C) and long-term storage (several years), due to battery leakage and self-discharge phenomenon, the traditional disposable dry battery can not guarantee smooth operation, therefore, there are still some The use of the situation is traditionally not covered by a dry battery.

The invention provides a primary aluminum air battery, which can be stored for a long time and needs to be discharged through the starting mechanism when in use.

The invention provides a primary aluminum air battery comprising at least a container, a battery pack, a water absorbing material, an electrolyte, and an active starting device. The above battery pack is placed in a container, and the battery pack is composed of an aluminum anode and an air electrode cathode. The water absorbing material is filled around the battery pack in the container. The electrolyte is placed in the container and is not in contact with the battery pack. As for the active starting device, there is a mechanism for actively contacting the electrolyte with the battery pack.

In an embodiment of the invention, the aluminum anode is a pure aluminum or aluminum alloy having a purity of 85 wt.% to 99.999 wt.%.

In an embodiment of the invention, the aluminum anode is an aluminum alloy, and includes at least one of magnesium, iron, copper, calcium, barium, indium, zinc, gallium, tin, cadmium, antimony, bismuth, selenium, tellurium and mercury. metal.

In an embodiment of the invention, the aluminum anode has a thickness of between 1 mm and 0.1 mm.

In an embodiment of the invention, the aluminum anode is a block, a membrane or Porous mesh.

In an embodiment of the invention, the air electrode cathode comprises a catalyst, wherein the catalyst comprises a metal oxide such as MnO ₂ or CoO. The catalyst can also be Pt/C.

In an embodiment of the invention, the water absorbing material comprises a material composed of cellulose or fibers.

In an embodiment of the invention, the electrolyte comprises an aqueous solution that is alkaline, neutral or acidic.

In an embodiment of the invention, the primary aluminum air battery may further include a film covering the electrolyte to prevent the electrolyte from contacting the battery pack.

In an embodiment of the invention, the mechanism of the active starting device includes a breaking device to actively break the film covering the electrolyte to bring the electrolyte into contact with the battery pack.

In an embodiment of the invention, the primary aluminum air battery may further include a separator disposed between the membrane covering the electrolyte and the battery pack, and the separator has at least one through hole.

In an embodiment of the invention, the mechanism of the active starting device comprises a partition, a spigot and a plucking device. The separator is disposed between the electrolyte and the battery pack, and the separator has a through hole. The insertion hole blocks the through hole, and the plucking device is connected with the spigot to remove the spigot from the through hole, so that the electrolyte contacts the battery pack through the through hole.

Based on the above, the primary aluminum air battery of the present invention can be stored for a long period of time by separating the electrolyte and the battery pack, and the discharge is started only when the electrolyte is brought into contact with the battery pack through the mechanism.

The above described features and advantages of the present invention will be more apparent from the following description.

1A is an exploded perspective view of a primary aluminum air battery in accordance with a first embodiment of the present invention.

Referring to FIG. 1A, a primary aluminum air battery 100 of the present embodiment includes a container 102, a battery pack 104 placed in the container 102, a water absorbing material 106, an electrolyte 108, and an active starting device 110. The battery pack 104 is composed of an aluminum anode 112 and an air electrode cathode 114. Since the electrolyte 108 is an alkaline, neutral or acidic aqueous solution, in the present embodiment, the electrolyte 108 is coated with the membrane 116 to avoid contact with the battery pack 104. However, this layer of film 116 is not necessary and this layer of film 116 encasing the electrolyte 108 may be omitted in a suitably designed container. The container 102 is generally a non-conductor, such as a plastic container, and its configuration may be varied as desired, as shown in Fig. 1A in a cylindrical shape, but the invention is not limited thereto. The air electrode cathode 114 is generally located at the periphery of the vessel 102 and is reactive with air.

As for the active starting device 110, there is a mechanism for actively contacting the electrolyte 108 with the battery pack 104; that is, the present embodiment achieves the effect of the electrolyte 108 contacting the battery pack 104 by the movement of the electrolyte 108, and the battery pack 104 is There will be no action, but it will be passive. A detailed mechanism regarding the active starting device 110 will be described below.

In the present embodiment, the aluminum anode 112 may be pure aluminum or aluminum alloy having a purity of 85 wt.% to 99.999 wt.%. If the aluminum anode 112 is an aluminum alloy, then It may include at least one metal selected from the group consisting of magnesium, iron, copper, calcium, barium, indium, zinc, gallium, tin, cadmium, antimony, bismuth, selenium, tellurium and mercury. Taking magnesium as an example, the aluminum anode 112 may be an aluminum-5 wt.% to 15 wt.% magnesium alloy, but the invention is not limited thereto. Further, the thickness of the aluminum anode 112 is, for example, between 1 mm and 0.1 mm. The aluminum anode 112 may be a porous mesh material in addition to a block or a film as shown in FIG. 1A.

In the present embodiment, the air electrode cathode 114 may include a catalyst. The catalyst is, for example, a metal oxide such as MnO ₂ or CoO; or a catalyst such as Pt/C.

In the present embodiment, the water absorbing material 106 is, for example, a material composed of cellulose or fiber, and the B region of FIG. 1A is viewed from the above angle (as shown in FIG. 1B ), and it can be seen that the water absorbing material 106 is filled in the container 102 . The aluminum anode 112 and the air electrode cathode 114 are surrounded so that the primary air battery 100 is required to be fully diffused into and in contact with the aluminum anode 112 and the air electrode cathode 114.

In addition, a spacer 118 may be disposed between the film 116 encasing the electrolyte 108 and the battery pack 104 in FIG. 1A, and the spacer 118 may have a plurality of through holes 118a, for example. However, this layer of separator 118 is not necessary and may be omitted in a suitably designed container.

The mechanism of the active starting device 110 in this embodiment is a breaking device having a pointed cone 120 capable of actively destroying the membrane 116 encasing the electrolyte 108 to bring the electrolyte 108 into contact with the underlying battery pack 104. However, the active starting device 100 of FIG. 1A is only one example, and the active starting device of the present invention may have other embodiments. When the components in FIG. 1A are combined, as shown in FIG. 1C, the electrolyte 108 covered by the film 116 is coated. Placed within the container 102 and not in contact with the battery pack 104, the active activation device 110 is disposed over the electrolyte 108 with the tip 120 facing the electrolyte 108. When the aluminum air battery 100 is not used, since the electrolyte 108 is separated from the battery pack 104, it can be stored for a long period of time. When it is used, only the active starting device 110 needs to be moved to destroy the film covering the electrolyte 108, as shown in the figure. As shown in Fig. 1, the electrolyte 108 can be directly penetrated through the through hole 118a of the spacer 118 to contact the bottom battery pack 104, and discharge begins. Even if the container 102 of FIG. 1D is placed horizontally or inverted, the electrolyte 108 is diffused to the string, parallel battery pack 104 via the water absorbing material 106 filled around the aluminum anode 112 and the air electrode cathode 114.

2A is a perspective perspective view of a primary aluminum air battery in accordance with a second embodiment of the present invention.

Referring to FIG. 2A, the primary aluminum air battery 200 of the present embodiment includes a container 202, a battery pack 204 placed in the container 202, a water absorbing material 206, an electrolyte 208, and an active starting device 210. The battery pack 204 is composed of an aluminum anode 212 and an air electrode cathode 214. The container 202, the battery pack 204, the water absorbing material 206 and the electrolyte 208 of the present embodiment can be referred to the previous embodiment, and therefore will not be described again.

Since the electrolyte 208 is an alkaline, neutral or acidic aqueous solution, the mechanism of the active activation device 210 includes a diaphragm 216, a spigot 218, and a plucking device 220. The separator 216 is disposed between the electrolyte 208 and the battery pack 204 for separating the electrolyte 208 from the battery pack 204, and the partition 216 has a through hole, and the plug 218 blocks the through hole, and FIG. 2A shows only one. Through hole, but the invention is not limited thereto. The plucking device 220 and the spigot 218 Connected, the ferrule 218 can be removed from the through hole 216a when the primary aluminum air battery 200 is used, as shown in FIG. 2B.

When the ferrule 218 is removed from the through hole 216a, the electrolyte 208 will flow through the through hole 216a to contact the battery pack, and the battery pack 204 does not need to be operated. Moreover, even if the container 202 of FIG. 2B is placed horizontally or inverted, the electrolyte 208 diffuses to the battery pack 204 through the water absorbing material 206 filled around the aluminum anode 212 and the air electrode cathode 214, and begins to discharge.

An experimental result is enumerated below to verify the effects of the above embodiment.

experiment

First, a primary aluminum air battery 300 as shown in FIG. 3A is constructed, which is composed of four sets of aluminum anode-air battery cells 302, and placed in a container 304, and has a breaking device 308 including a tapered cone 306. The positions of the aluminum anode 310 and the air electrode 312 of the battery pack 302, the electrolyte 314 (coated with the film), and the water absorbing material 316 are shown in the figure, and the materials thereof are: aluminum anode: AA1050 aluminum alloy (3.271 g).

Air electrode: The catalyst is MnO ₂ (weight of 18.559 g with the plastic case).

Electrolyte: 4 M KOH + 0.18 M ZnCl ₂ (13.899 g).

Water absorbing material: cotton (2.263 g).

When the primary aluminum air battery 300 is in operation, the destruction device 308 is mounted, as shown in Fig. 3B. The tip cone 306 pierces the film (not shown) of the coated electrolyte 314, and causes the electrolyte 314 inside the film to flow into the water absorbing material 316, and the primary aluminum air battery 300 starts the discharge reaction. The discharge curve of the battery pack constructed in FIG. 3B is as shown in FIG. 4. Under the current load condition of 100 mA, the discharge voltage of the primary aluminum air battery 300 is between 4.5 and 6 V. The discharge time can be as long as 800,000 seconds (about 9.26 days).

In summary, the device of the present invention separates the electrolyte from the electrode before using the battery, and re-mixes and activates the battery during use. This design concept can improve battery storage time.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. The scope of the invention is defined by the scope of the appended claims.

100, 200, 300‧‧‧Aluminum air battery

102, 202, 304‧‧‧ containers

104, 204, 302‧‧‧ battery pack

106, 206, 316‧‧‧ water-absorbing materials

108, 208, 314‧‧‧ electrolyte

110, 210‧‧‧Active starter

112, 212, 310‧‧‧Aluminum anode

114, 214, 312‧‧ Air electrode cathode

116‧‧‧membrane

118, 216‧‧ ‧ partition

118a, 216a‧‧‧through holes

308‧‧‧ destruction device

120, 306‧‧ ‧ sharp cone

218‧‧‧ 插插

220‧‧‧ removal device

B‧‧‧Area

1A is an exploded perspective view of a primary aluminum air battery in accordance with a first embodiment of the present invention.

Fig. 1B is a top view of the area B of Fig. 1A.

Fig. 1C is a combination view of the components of Fig. 1A.

Fig. 1D is a schematic view showing the use of the primary aluminum air battery of the first embodiment.

2A is a perspective perspective view of a primary aluminum air battery in accordance with a second embodiment of the present invention.

Fig. 2B is a schematic view showing the use of the primary aluminum air battery of the second embodiment.

Figure 3A is a schematic illustration of an experimental primary aluminum air battery.

Figure 3B is a schematic illustration of the use of an experimental aluminum air battery.

Fig. 4 is a graph showing the discharge of the battery pack of Fig. 3B.

100‧‧‧Aluminum air battery

102‧‧‧ Container

104‧‧‧Battery Pack

106‧‧‧Water-absorbing materials

108‧‧‧ Electrolytes

110‧‧‧Active starter

112‧‧‧Aluminum anode

114‧‧‧Air electrode cathode

116‧‧‧membrane

118‧‧‧Baffle

118a‧‧‧through hole

120‧‧‧spirit

B‧‧‧Area

Claims (13)

A primary aluminum air battery comprising: a container; a battery pack disposed in the container, the battery pack being composed of an aluminum anode and an air electrode cathode; a water absorbing material filled around the aluminum anode and the air electrode cathode; the electrolyte Disposed in the container and not in contact with the battery pack; a membrane covering the electrolyte to make the electrolyte not in contact with the battery; and an active starting device having the electrolyte actively contacting the battery The mechanism includes a destruction device to actively destroy the membrane covering the electrolyte to bring the electrolyte into contact with the battery pack. The primary aluminum air battery of claim 1, wherein the aluminum anode is pure aluminum or an aluminum alloy having a purity of 85 wt.% to 99.999 wt.%. The primary aluminum air battery of claim 1, wherein the aluminum anode is an aluminum alloy. The primary aluminum air battery according to claim 3, wherein the aluminum alloy comprises magnesium, iron, copper, calcium, barium, indium, zinc, gallium, tin, cadmium, antimony, bismuth, selenium, tellurium and mercury. At least one metal. The primary aluminum air battery of claim 1, wherein the aluminum anode has a thickness of between 1 mm and 0.1 mm. A primary aluminum air battery as described in claim 1 of the patent scope, The aluminum anode is a block, a membrane or a porous mesh. The primary aluminum air battery of claim 1, wherein the air electrode cathode comprises a catalyst. The primary aluminum air battery of claim 7, wherein the catalyst comprises a metal oxide. The primary aluminum air battery of claim 8, wherein the metal oxide comprises MnO ₂ or CoO. The primary aluminum air battery of claim 7, wherein the catalyst comprises Pt/C. The primary aluminum air battery of claim 1, wherein the water absorbing material comprises a material composed of cellulose or fiber. The primary aluminum air battery of claim 1, wherein the electrolyte comprises an alkaline, neutral or acidic aqueous solution. The primary aluminum air battery of claim 1, further comprising a separator disposed between the membrane covering the electrolyte and the battery pack, wherein the separator has at least one through hole.