Aluminum air battery low-temperature electrolyte and application thereof

Abstract

The invention discloses an aluminum-air battery low-temperature electrolyte and application thereof, and relates to the technical field of aluminum-air batteries, the aluminum-air battery low-temperature electrolyte comprises a reference electrolyte and a supplementary electrolyte, the reference electrolyte comprises a solvent, a solute and an additive, the solvent is water, the solute is at least one of KOH or NaOH, and the additive is an additive. The additive is one or more of sodium chloride, potassium chloride, glucose, potassium citrate, ethylene glycol and polyethylene glycol; the supplementary electrolyte is a mixture of solid alkali and solid acid; the reference electrolyte and the supplementary electrolyte are stored separately, and when the electrolyte is used, the supplementary electrolyte is added into the reference electrolyte. The low-temperature electrolyte provided by the invention is low in raw material price, convenient and easy to obtain, simple in use method and easy to operate; and the battery can stably operate in a low-temperature environment of minus 40 DEG C, and can meet the use requirements of a power supply in a plateau cold region.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum-air batteries, and more specifically, to a low-temperature electrolyte for aluminum-air batteries and applications thereof. Background Art

[0002] Energy is the material basis for the survival and development of human society. Aluminum-air batteries, as a clean energy with many excellent characteristics such as high specific energy, low infrared radiation, no noise, non-flammable and non-explosive raw materials, high safety, long-term maintenance-free, green and pollution-free, have received widespread attention. In order to ensure the battery power and operating time, alkaline aqueous electrolytes are usually selected. However, in a low-temperature environment of -40℃, the activity of commonly used alkaline aqueous electrolytes is greatly reduced, and the battery can hardly discharge, which seriously limits the application of aluminum-air batteries in cold climates and extremely cold environments. At present, there are few reports on the research of low-temperature electrolytes. Summary of the invention

[0003] In view of this, the main purpose of the present invention is to provide a low-temperature electrolyte for an aluminum-air battery. The electrolyte provided by the present invention can enable the battery to operate stably in a low-temperature environment of minus 40°C, and can meet the power supply requirements in plateau cold areas.

[0004] To achieve the above object, the technical solution of the present invention is as follows:

[0005] A low-temperature electrolyte for an aluminum-air battery comprises a reference electrolyte and a supplementary electrolyte, wherein the reference electrolyte comprises a solvent, a solute and an additive, wherein the solvent is water, the solute is at least one of KOH or NaOH, and the additive is one or more of sodium chloride, potassium chloride, glucose, potassium citrate, ethylene glycol and polyethylene glycol; the supplementary electrolyte is a mixture of a solid base and a solid acid; the reference electrolyte and the supplementary electrolyte are stored separately, and when used, the supplementary electrolyte is added to the reference electrolyte.

[0006] Furthermore, the concentration of the solute in the reference electrolyte is 1-8 mol / L; the content of the potassium chloride or sodium chloride is 20-100 g / L; the content of the glucose is 50-100 g / L; the content of the potassium citrate is 20-50 g / L; and the content of the ethylene glycol or polyethylene glycol is 20-50 mL / L.

[0007] Wherein, the polyethylene glycol is polyethylene glycol 200, and the molecular weight is 190-210.

[0008] Furthermore, the solid base includes KOH or NaOH.

[0009] Furthermore, the solid acid includes oxalic acid, malonic acid, adipic acid, citric acid, stearic acid or palmitic acid.

[0010] Furthermore, in the supplementary electrolyte, the content of the solid base is 1 to 4 mol / L.

[0011] Furthermore, in the supplementary electrolyte, the content of the solid acid is 50 to 200 g / L.

[0012] The second purpose of the present invention is to provide the application of any of the above-mentioned aluminum-air battery low-temperature electrolytes in aluminum-air batteries at minus 40°C.

[0013] Furthermore, the application comprises the following steps:

[0014] 1) First prepare a reference electrolyte for storage;

[0015] Using water as solvent, adding solute to prepare a solution with a concentration of 1 to 8 mol / L, then adding additives, stirring for 5 to 10 minutes until completely dissolved, to obtain a reference electrolyte;

[0016] 2) When the temperature of the reference electrolyte is -40°C, add the supplementary electrolyte to the reference electrolyte and stir for 2 to 5 minutes. After the reaction is complete and the electrolyte temperature rises, add the high-temperature electrolyte into the battery and the battery can be started.

[0017] The present invention also aims to provide an aluminum-air battery containing any of the aluminum-air battery low-temperature electrolytes described above.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] (1) The raw materials of the aluminum-air battery low-temperature electrolyte of the present invention are cheap, easily available, and the method of use is simple and easy to operate;

[0020] (2) The low-temperature electrolyte of the present invention innovatively stores a low-concentration aqueous reference electrolyte separately from a supplementary solid material, i.e., a supplementary electrolyte package, and innovatively adds additives such as sodium chloride, potassium chloride, potassium citrate, ethylene glycol, and / or polyethylene glycol to the aqueous reference electrolyte, thereby preventing the reference electrolyte from solidifying in a low-temperature environment of -40°C for a long time. When in use, the supplementary electrolyte is added, and the heat generated by the dissolution and neutralization reaction is used to increase the electrolyte temperature, thereby achieving the purpose of starting the aluminum-air power supply.

[0021] (3) The electrolyte of the present invention can enable the aluminum-air power source to start at rated power within 7 minutes in a low-temperature environment of -40°C, and operate stably at constant power for 4 hours and 25 minutes. After the reaction is completed, it can still be left stationary in a low-temperature environment of -40°C for 1 hour and 15 minutes. The power supply cooling ensures that the reaction will not get out of control, thus meeting the power supply use requirements in plateau cold areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1The invention relates to an aluminum-air battery.

[0023] Figure 2 It is a time-power / temperature curve diagram of the power startup process in Example 1 of the present invention.

[0024] Figure 3 It is a time-voltage / current / temperature curve diagram of the power supply working process in Example 1 of the present invention.

[0025] Figure 4 It is a time-power / temperature curve diagram of the power startup process in comparative example 1 of the present invention.

[0026] Figure 5 It is a time-voltage / current / temperature curve diagram of the power supply working process in comparative example 2 of the present invention.

[0027] Figure 6 This is a picture of the reference electrolyte in Comparative Example 3 of the present invention being frozen after being stored in a -40°C environment for 4 hours.

[0028] Figure 7 This is a picture of the runaway reaction after the power supply in Comparative Example 4 of the present invention was operated at a constant power of 20W for 2h36min. DETAILED DESCRIPTION

[0029] Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar modifications without violating the connotation of the present invention, so the present invention is not limited to the specific implementation disclosed below.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0031] Example 1

[0032] Weigh the reference electrolyte according to Table 1, add appropriate amount of water, stir for 10 min to obtain 300 mL of reference electrolyte, weigh the supplementary additive according to Table 2, store the aluminum air power source, 300 mL of reference electrolyte, and the supplementary additive package in a -40°C environment for 4 h;

[0033] Table 1 Ingredients of reference electrolyte (300mL)

[0034] Element NaOH NaCl glucose Potassium Citrate Ethylene glycol Mass / Volume 72g 15g 25g 10g 10mL

[0035] Table 2 Ingredients of Supplementary Additives (300mL)

[0036] Element NaOH Oxalic acid quality 50.4g 30g

[0037] When using, add the supplementary additive package to the reference electrolyte, stir rapidly for 5 minutes, react until completely dissolved, and obtain 350mL of electrolyte. Add the electrolyte to the Figure 1 In the aluminum-air power supply shown in the figure, the battery is started and the output power is gradually increased by using the load device until the rated power of 20W is reached. Then the constant power is operated until the load cannot reach 20W. The time-power / temperature curve of the power loading process is shown in Figure 2 , constant power 20W operation process time-voltage / current / temperature curve as follows Figure 3 The time required from the completion of electrolyte addition to the loading of rated power of 20W is 7 minutes, and the 20W constant power runs for 4 hours and 25 minutes. After unloading, it is left to stand in a -40℃ environment for 1 hour and 15 minutes, and the power supply temperature drops to 15.2℃, and there is no runaway reaction.

[0038] Example 2

[0039] Weigh the reference electrolyte according to Table 3, add appropriate amount of water, stir for 10 min to obtain 300 mL of reference electrolyte, weigh the supplementary additive according to Table 4, store the aluminum air power source, 300 mL of reference electrolyte, and the supplementary additive package in a -40°C environment for 4 h;

[0040] Table 3 Ingredients of reference electrolyte (300mL)

[0041] Element KOH KCl glucose Potassium Citrate Polyethylene glycol Mass / Volume 67.2g 20g 25g 10g 10mL

[0042] Table 4 Ingredients of Supplementary Additives (300mL)

[0043] Element KOH Oxalic acid quality 50.4g 30g

[0044] Among them, polyethylene glycol is polyethylene glycol 200 with a molecular weight of 190-210; when in use, add the supplementary additive package to the reference electrolyte, stir rapidly for 5 minutes, react until completely dissolved, and obtain 350mL of electrolyte, add the electrolyte to the aluminum air power supply in time, start the battery, and use the load equipment to gradually increase the output power until the rated power of 20W is reached, and then operate at a constant power until 20W cannot be loaded. The time required from the completion of the addition of the electrolyte to the loading of the rated power of 20W is 8min15s, and the constant power operation of 20W is 4h3min. After unloading, it is allowed to stand in a -40℃ environment for 1h, and the power supply temperature drops to 29.2℃, and there will be no reaction out of control.

[0045] Comparative Example 1

[0046] Weigh electrolyte according to Table 5, add appropriate amount of water, stir for 10 minutes, and obtain 350mL electrolyte;

[0047] Table 5 Ingredients of electrolyte (350mL)

[0048] Element NaOH NaCl glucose Potassium Citrate Ethylene glycol Oxalic acid Mass / Volume 122.4g 15g 25g 10g 10mL 30g

[0049] The above electrolyte was stored in a -40℃ environment for 4 hours. When in use, the electrolyte was added to a 20W aluminum-air power supply, and the load device was connected to gradually increase the output power. It was found that the power supply temperature basically did not change, and only 0.3W of power could be loaded within 1 hour. The time-power / temperature curve of the power supply startup process is shown in Figure 2. Figure 4 .

[0050] Comparative Example 2

[0051] Weigh the reference electrolyte according to Table 6, add appropriate amount of water, stir for 10 min to obtain 300 mL of reference electrolyte, weigh the supplementary additive according to Table 7, store the aluminum air power source, 300 mL of reference electrolyte, and the supplementary additive package in a -40°C environment for 4 h;

[0052] Table 6 Ingredients of reference electrolyte (300mL)

[0053] Element NaOH NaCl glucose Potassium Citrate Ethylene glycol Mass / Volume 72g 15g 0g 10g 10mL

[0054] Table 7 Ingredients of Supplementary Additives (300mL)

[0055] Element NaOH Oxalic acid quality 50.4g 30g

[0056] When using, add the supplementary additive package to the reference electrolyte, stir rapidly for 5 minutes, react until completely dissolved, and obtain 350mL of electrolyte. Add the electrolyte to the Figure 1 In the aluminum-air power supply shown in the figure, the battery is started and the output power is gradually increased by using the load device until the rated power reaches 20W. After running at constant power for 3h9min, the load is removed. The time-voltage / current / temperature curve of the running process is as follows: Figure 5 shown.

[0057] Comparative Example 3

[0058] Weigh the reference electrolyte according to Table 8, add appropriate amount of water, stir for 10 min to obtain 300 mL of reference electrolyte, weigh the supplementary additive according to Table 9, store the aluminum air power source, 300 mL of reference electrolyte, and the supplementary additive package in a -40°C environment for 4 h;

[0059] Table 8 Ingredients of reference electrolyte (300mL)

[0060] Element NaOH NaCl glucose Potassium Citrate Ethylene glycol Mass / Volume 72g 15g 25g 10g 0mL

[0061] Table 9 Ingredients of Supplementary Additives (300mL)

[0062] Element NaOH Oxalic acid quality 50.4g 30g

[0063] After the reference electrolyte was stored at -40℃ for 4 hours, the electrolyte solidified. Figure 6 ,not available.

[0064] Comparative Example 4

[0065] Weigh the reference electrolyte according to Table 10, add appropriate amount of water, stir for 10 min to obtain 300 mL of reference electrolyte, weigh the supplementary additive according to Table 11, store the aluminum air power source, 300 mL of reference electrolyte, and the supplementary additive package in a -40°C environment for 4 h;

[0066] Table 10 Ingredients of reference electrolyte (300mL)

[0067] Element NaOH NaCl glucose Potassium Citrate Ethylene glycol Mass / Volume 122.4g 15g 25g 10g 10mL

[0068] Table 11 Ingredients of Supplementary Additives (300mL)

[0069] Element NaOH Oxalic acid quality 50.4g 30g

[0070] When using, add the supplementary additive package to the reference electrolyte, stir rapidly for 5 minutes, react until completely dissolved, and obtain 350mL of electrolyte. Add the electrolyte to the Figure 1 In the aluminum-air power supply shown in the figure, the battery is started and the output power is gradually increased by using the load device until the rated power reaches 20W. After running at a constant power of 20W for 2h36min, the battery reacts out of control, as shown in Figure 7 .

[0071] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0072] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A low-temperature electrolyte for an aluminum-air battery, characterized in that: It comprises a reference electrolyte and a supplementary electrolyte, wherein the reference electrolyte comprises a solvent, a solute and an additive, wherein the solvent is water, the solute is at least one of KOH or NaOH, and the additive is one or more of sodium chloride, potassium chloride, glucose, potassium citrate, ethylene glycol and polyethylene glycol; the supplementary electrolyte is a mixture of a solid base and a solid acid; the reference electrolyte and the supplementary electrolyte are stored separately, and when in use, the supplementary electrolyte is added to the reference electrolyte.

2. The aluminum-air battery low-temperature electrolyte according to claim 1, characterized in that: The concentration of the solute in the reference electrolyte is 1-8 mol / L; the content of the potassium chloride or sodium chloride is 20-100 g / L; the content of the glucose is 50-100 g / L; the content of the potassium citrate is 20-50 g / L; and the content of the ethylene glycol or polyethylene glycol is 20-50 mL / L.

3. The aluminum-air battery low-temperature electrolyte according to claim 1, characterized in that: The solid base includes KOH or NaOH.

4. The aluminum-air battery low-temperature electrolyte according to claim 1, characterized in that: The solid acid includes oxalic acid, malonic acid, adipic acid, citric acid, stearic acid or palmitic acid.

5. The aluminum-air battery low-temperature electrolyte according to claim 1, characterized in that: In the supplementary electrolyte, the content of the solid alkali is 1 to 4 mol / L.

6. The aluminum-air battery low-temperature electrolyte according to claim 1, characterized in that: In the supplementary electrolyte, the content of the solid acid is 50 to 200 g / L.

7. Application of the aluminum-air battery low-temperature electrolyte according to any one of claims 1-6 in an aluminum-air battery at -40°C.

8. The use according to claim 7, characterized in that: The following steps are involved: 1) First prepare a reference electrolyte for storage; Using water as solvent, adding solute to prepare a solution with a concentration of 1 to 8 mol / L, then adding additives, stirring for 5 to 10 minutes until completely dissolved, to obtain a reference electrolyte; 2) When the temperature of the reference electrolyte is -40°C, add the supplementary electrolyte to the reference electrolyte and stir for 2 to 5 minutes. After the reaction is complete and the electrolyte temperature rises, add the high-temperature electrolyte into the battery and the battery can be started.

9. An aluminum-air battery, characterized in that: Contains the aluminum-air battery low-temperature electrolyte described in any one of claims 1-6.

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