A mold that enables dual-electrolyte lithium-air batteries to operate in pure oxygen

Abstract

The present invention relates to a mold that enables a dual-electrolyte lithium-air battery to operate in pure oxygen. The technical solution is as follows: it includes a positive electrode housing, a negative electrode housing, a gas pressure gauge, a positive electrode sheet, a preload spring, and an oxygen transmission pipeline. The upper center portion of the positive electrode housing is an oxygen chamber, and the lower portion is a positive electrode chamber. The top of the negative electrode housing is provided with a negative electrode chamber, and the positive electrode housing is fixedly mounted above the negative electrode housing. The upper inner wall of the oxygen chamber is provided with a preload thread, and the gas pressure gauge is screwed to the positive electrode housing via the preload thread. The positive electrode sheet is placed on the bottom wall of the oxygen chamber. The preload spring is disposed between the gas pressure gauge and the positive electrode sheet, and the gas pressure gauge cooperates with the preload thread to secure the preload spring to the positive electrode sheet. The oxygen transmission pipeline penetrates the side wall of the positive electrode housing and communicates with the oxygen chamber. The present invention can transmit oxygen and prevent electrolyte evaporation, thereby improving the electrochemical performance of the battery.

Description

Technical Field

[0001] The present invention relates to a lithium-air battery, in particular to a mould capable of enabling a dual-electrolyte lithium-air battery to operate in pure oxygen. Background Art

[0002] The energy density of lithium-ion batteries has reached its theoretical limit. With the continuous improvement of people's living standards, the demand for efficient energy has increased. Rechargeable metal-air batteries have become a research hotspot in the field of scientific research due to their ultra-high energy density. Among many metal-air batteries, lithium-air batteries have the highest theoretical energy density of 11140Wh kg -1 Dual-electrolyte lithium-air batteries have attracted widespread attention due to their low overpotential, safe and harmless aqueous electrolyte, and the fact that the discharge product, LiOH, dissolves in water without clogging the positive electrode. Therefore, dual-electrolyte lithium-air batteries are the most promising energy storage systems. However, current dual-electrolyte lithium-air battery molds suffer from low discharge capacity, rapid evaporation of the aqueous electrolyte when the battery operates directly in air, and clogging of the positive electrode due to the reaction of impurities in the air with the electrolyte. Summary of the Invention

[0003] The present invention provides a mold that can enable a dual-electrolyte lithium-air battery to operate in pure oxygen. The mold can transmit oxygen to the dual-electrolyte lithium-air battery and the overall seal can effectively prevent electrolyte evaporation, thereby improving the electrochemical performance of the battery.

[0004] The technical solutions of the present invention are as follows:

[0005] A mold capable of enabling a dual-electrolyte lithium-air battery to operate in pure oxygen comprises a positive electrode shell, a negative electrode shell, a gas pressure gauge, a positive electrode sheet, a pre-tightening spring and an oxygen transmission pipeline, wherein the upper center portion of the positive electrode shell is an oxygen chamber, the lower center portion is a positive electrode chamber, the top of the negative electrode shell is provided with a negative electrode chamber, and the positive electrode shell is fixedly arranged above the negative electrode shell; the upper inner wall of the oxygen chamber is provided with a pre-tightening thread, the gas pressure gauge is screwed to the positive electrode shell via the pre-tightening thread, the positive electrode sheet is placed on the bottom wall of the oxygen chamber, the pre-tightening spring is arranged between the gas pressure gauge and the positive electrode sheet, the gas pressure gauge cooperates with the pre-tightening thread to make the pre-tightening spring close to the positive electrode sheet; the oxygen transmission pipeline penetrates the side wall of the positive electrode shell and communicates with the oxygen chamber.

[0006] Furthermore, in the mold capable of realizing the dual-electrolyte lithium-air battery operating in pure oxygen, the side of the positive electrode shell is provided with a positive electrode current collector, and the side of the negative electrode shell is provided with a negative electrode current collector; the materials of the positive electrode shell, the negative electrode shell, the positive electrode current collector and the negative electrode current collector are all made of stainless steel.

[0007] Furthermore, in the mold capable of realizing the dual-electrolyte lithium-air battery operating in pure oxygen, a non-woven fabric separator is provided below the positive electrode sheet; the positive electrode sheet material is carbon paper; and the non-woven fabric separator material is polypropylene.

[0008] Furthermore, in the mold that can realize the operation of the dual-electrolyte lithium-air battery in pure oxygen, the oxygen chamber is connected to the positive electrode chamber, the inner diameter of the oxygen chamber is larger than the inner diameter of the positive electrode chamber, and the bottom wall of the oxygen chamber is annular; the non-woven fabric diaphragm is placed on the bottom wall of the oxygen chamber, the positive electrode sheet is placed on the non-woven fabric diaphragm, and the pre-tightening spring presses the positive electrode sheet and the non-woven fabric diaphragm against the bottom wall of the oxygen chamber.

[0009] Furthermore, in the mold capable of realizing the dual-electrolyte lithium-air battery operating in pure oxygen, the positive electrode shell and the negative electrode shell are fixedly connected by bolts.

[0010] Furthermore, in the mold capable of realizing the dual-electrolyte lithium-air battery operating in pure oxygen, a sealing gasket is provided between the positive electrode shell and the negative electrode shell, and a sealing ring is provided between the gas pressure gauge and the positive electrode shell.

[0011] Furthermore, in the mold capable of realizing the dual-electrolyte lithium-air battery operating in pure oxygen, a solid electrolyte membrane is provided at the lower end of the positive electrode cavity, and the solid electrolyte membrane material is conductive ceramic.

[0012] Furthermore, in the mold capable of realizing the dual-electrolyte lithium-air battery to operate in pure oxygen, a positive electrode electrolyte is placed in the positive electrode cavity.

[0013] Furthermore, in the mold capable of realizing the dual-electrolyte lithium-air battery operating in pure oxygen, a negative electrode module is provided in the negative electrode cavity.

[0014] Furthermore, in the mold capable of realizing the dual-electrolyte lithium-air battery operating in pure oxygen, the gas transmission pipeline is connected to the oxygen cylinder, and oxygen is transmitted into the oxygen chamber through the gas transmission pipeline.

[0015] The beneficial effects of the present invention are:

[0016] 1. In the present invention, the positive electrode shell is provided with an oxygen transmission pipeline to introduce oxygen into the oxygen chamber. The positive electrode reactant contains only oxygen and no other impurity gases, thereby preventing other impurities in the air from reacting with the electrolyte. At the same time, the entire device is sealed to prevent the evaporation of the electrolyte, thereby improving the overall performance of the dual-electrolyte lithium-air battery.

[0017] 2. The present invention rotates the gas pressure gauge to cause the preload spring to compress the positive electrode sheet, effectively preventing electrolyte evaporation. Simultaneously, the non-woven fabric separator prevents evaporation of the positive electrode electrolyte and prevents it from washing away the catalyst.

[0018] 3. A positive electrode current collector is provided on the side of the positive electrode shell and a negative electrode current collector is provided on the side of the negative electrode shell, making it easy to connect when testing the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of a mold that enables a dual-electrolyte lithium-air battery to operate in pure oxygen;

[0020] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0021] Figure 3 These are the first cycle constant current and constant capacity charge and discharge test diagrams under the action of air and oxygen respectively. DETAILED DESCRIPTION

[0022] like Figure 1-2 As shown, a mold that can realize a dual-electrolyte lithium-air battery working in pure oxygen includes a positive electrode shell 6, a negative electrode shell 5, a gas pressure gauge 1, a positive electrode sheet, a preload spring 8 and an oxygen transmission pipeline 7. The upper center part of the positive electrode shell 6 is an oxygen chamber 9, and the lower part is a positive electrode chamber 10. The oxygen chamber 9 is connected to the positive electrode chamber 10. The inner diameter of the oxygen chamber 9 is larger than the inner diameter of the positive electrode chamber 10, and the bottom wall of the oxygen chamber 9 is annular; a negative electrode chamber 11 is provided on the top of the negative electrode shell 5, and a negative electrode module is provided in the negative electrode chamber 11; the positive electrode shell 6 is fixedly arranged above the negative electrode shell 5, and a sealing gasket is provided between the positive electrode shell 6 and the negative electrode shell 5, and the positive electrode shell 6 and the negative electrode shell 5 are fixedly connected by bolts 2; a positive electrode current collector 3 is provided on the side of the positive electrode shell 6, and a negative electrode current collector 4 is provided on the side of the negative electrode shell 5; the materials of the positive electrode shell 6, the negative electrode shell 5, the positive electrode current collector 3 and the negative electrode current collector 4 are all made of Stainless steel; a pre-tightening thread is provided on the upper inner wall of the oxygen chamber 9, and the gas pressure gauge 1 is screwed to the positive electrode shell 6 through the pre-tightening thread, and a sealing ring 12 is provided between the gas pressure gauge 1 and the positive electrode shell 6; a non-woven fabric diaphragm is placed on the bottom wall of the oxygen chamber 9, and the positive electrode sheet is placed on the non-woven fabric diaphragm, and a pre-tightening spring 8 is provided between the gas pressure gauge 1 and the positive electrode sheet, and the pre-tightening spring 8 presses the positive electrode sheet and the non-woven fabric diaphragm against the bottom wall of the oxygen chamber 9; the positive electrode sheet material is carbon paper; the non-woven fabric diaphragm material is polypropylene; a solid electrolyte membrane is provided at the lower end of the positive electrode chamber 10, and the solid electrolyte membrane material is conductive ceramic; a positive electrode electrolyte is placed in the positive electrode chamber 10; the oxygen transmission pipeline 7 penetrates the side wall of the positive electrode shell 6 and is connected to the oxygen chamber 9, and the gas transmission pipeline 7 is connected to the oxygen cylinder, and oxygen is transmitted to the oxygen chamber 9 through the gas transmission pipeline 7.

[0023] The mold preparation process for realizing a dual-electrolyte lithium-air battery operating in pure oxygen includes the following steps:

[0024] (1) Assemble in a glove box;

[0025] (2) The negative electrode module includes a lithium sheet, a glass fiber membrane and a negative electrode electrolyte; the lithium sheet is placed at the bottom of the negative electrode cavity 11, the glass fiber membrane is placed on the lithium sheet, and the negative electrode electrolyte is dripped onto the glass fiber membrane; the negative electrode electrolyte is LiTFSI-TEGDME;

[0026] (3) placing a solid electrolyte membrane at the lower end of the positive electrode chamber 10 and sealing it with epoxy resin;

[0027] (4) Adding a positive electrode electrolyte dropwise into the positive electrode chamber 10, wherein the positive electrode electrolyte is LiOH (1 mol / L);

[0028] (5) placing a non-woven fabric membrane on the bottom wall of the oxygen chamber 9 and placing the positive electrode sheet on the non-woven fabric membrane;

[0029] (6) Connect the positive electrode housing 6 and the negative electrode housing 5 with bolts 2, and place a sealing gasket between the positive electrode housing 6 and the negative electrode housing 5;

[0030] (7) Place the preload spring 8 on the positive electrode sheet; screw the gas pressure gauge 1 onto the positive electrode housing 6 via the preload thread, with a sealing ring 12 provided between the gas pressure gauge 1 and the positive electrode housing 6;

[0031] (8) Connect the oxygen transmission pipe 7 to the oxygen cylinder, and transmit oxygen to the oxygen chamber 9 through the gas transmission pipe 7; the gas pressure gauge 1 monitors the air pressure in the oxygen chamber 9.

[0032] The assembled dual-electrolyte lithium-air battery was subjected to constant current and constant capacity charge and discharge tests. The protection voltage was 1.5-5V, the current density of the battery charge and discharge test was 0.1mA / cm2, and the forward and reverse capacity was limited to 100mAh / g. Figure 3 This is the first cycle of constant current and constant volume charge and discharge tests in oxygen and air respectively. It can be seen that the dual-point electrolyte lithium-air battery working in pure oxygen has a smaller overpotential and a stable discharge platform, indicating that the dual-point electrolyte lithium-air battery working in pure oxygen has better electrochemical performance.

Claims

1. A mold capable of realizing a dual-electrolyte lithium-air battery operating in pure oxygen, characterized in that: The invention comprises a positive electrode shell, a negative electrode shell, a gas pressure gauge, a positive electrode sheet, a pre-tightening spring and an oxygen transmission pipeline, wherein the upper center portion of the positive electrode shell is an oxygen chamber and the lower part is a positive electrode chamber, the negative electrode shell is provided with a negative electrode chamber on the top, and the positive electrode shell is fixedly arranged above the negative electrode shell; the upper inner wall of the oxygen chamber is provided with a pre-tightening thread, the gas pressure gauge is screwed to the positive electrode shell through the pre-tightening thread, the positive electrode sheet is placed on the bottom wall of the oxygen chamber, and the pre-tightening spring is arranged between the gas pressure gauge and the positive electrode sheet; the oxygen transmission pipeline penetrates the side wall of the positive electrode shell and is connected with the oxygen chamber; a non-woven fabric diaphragm is provided below the positive electrode sheet; the oxygen chamber is connected with the positive electrode chamber, the non-woven fabric diaphragm is placed on the bottom wall of the oxygen chamber, and the positive electrode sheet is placed on the non-woven fabric diaphragm; a solid electrolyte membrane is provided at the lower end of the positive electrode chamber, a positive electrode electrolyte is placed in the positive electrode chamber, and a negative electrode module is provided in the negative electrode chamber.

2. The mold capable of realizing a dual-electrolyte lithium-air battery operating in pure oxygen according to claim 1, characterized in that: A positive electrode current collector is provided on the side of the positive electrode shell, and a negative electrode current collector is provided on the side of the negative electrode shell; the materials of the positive electrode shell, the negative electrode shell, the positive electrode current collector and the negative electrode current collector are all made of stainless steel.

3. The mold capable of realizing a dual-electrolyte lithium-air battery operating in pure oxygen according to claim 1, characterized in that: The material of the positive electrode sheet is carbon paper; the material of the non-woven fabric separator is polypropylene.

4. The mold capable of realizing a dual-electrolyte lithium-air battery operating in pure oxygen according to claim 1, characterized in that: The inner diameter of the oxygen chamber is greater than the inner diameter of the positive electrode chamber, and the bottom wall of the oxygen chamber is annular; the preload spring presses the positive electrode sheet and the non-woven fabric diaphragm against the bottom wall of the oxygen chamber.

5. The mold capable of realizing a dual-electrolyte lithium-air battery operating in pure oxygen according to claim 1, characterized in that: The positive electrode shell and the negative electrode shell are fixedly connected by bolts.

6. The mold capable of realizing a dual-electrolyte lithium-air battery operating in pure oxygen according to claim 1, characterized in that: A sealing gasket is provided between the positive electrode shell and the negative electrode shell, and a sealing ring is provided between the gas pressure gauge and the positive electrode shell.

7. The mold for realizing a dual-electrolyte lithium-air battery operating in pure oxygen according to claim 1, characterized in that: The solid electrolyte membrane material is conductive ceramic.

8. The mold capable of realizing a dual-electrolyte lithium-air battery operating in pure oxygen according to claim 1, characterized in that: The oxygen transmission pipeline is connected to the oxygen cylinder.

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