Lithium-oxygen primary battery
By converting lithium-oxygen batteries into primary cells with a non-aqueous electrolyte and reduced lithium content, the cost and energy density limitations of secondary lithium-oxygen batteries are addressed, resulting in a cost-effective and high-capacity lithium-oxygen primary cell.
Patent Information
- Application Number
- CN202410169683.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-01-12
- Filing Date
- 2024-02-06
- Publication Date
- 2025-07-15
AI Technical Summary
The existing lithium-oxygen secondary batteries have high cost and insufficient energy density, which limits the endurance of electric vehicles and drones, and the number of charges and discharges is limited.
The lithium oxygen battery is designed as a primary battery, and the electrolyte without contact coal is used to reduce the amount of lithium metal in the negative electrode. The positive electrode is prepared using porous conductive carbon materials and polymer adhesives. The negative electrode is made of lithium metal, and the electrolyte contains lithium salts and ether solvents.
It achieves low cost and high weight specific energy density, greatly improves the capacity, and provides a single discharge with a much higher capacity than the secondary battery.
Smart Images
Figure CN120319958A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a lithium-oxygen battery, and in particular to a primary lithium-oxygen battery. Background Art
[0002] With the rise of the electric vehicle and drone industries, storage batteries have received increasing attention. Lithium-ion batteries are the mainstream of current storage batteries. Although current lithium-ion batteries can meet the operating requirements of electric vehicles and drones, their energy density is still slightly insufficient. The weight-specific energy density of traditional lithium-ion batteries is approximately 300 Wh / kg. To improve the endurance of devices such as electric vehicles and drones, lithium-oxygen batteries (or lithium-air batteries) with higher energy density have been proposed. The energy density of lithium-oxygen batteries is about three times or more that of traditional lithium-ion batteries.
[0003] Current lithium-oxygen batteries are secondary batteries. To enable multiple charging and discharging cycles, a catalyst must be added to the electrolyte of lithium-oxygen batteries, and the negative electrode capacity also needs to be increased to avoid the rapid depletion of highly active lithium metal at the negative electrode. Therefore, the N / P ratio of current lithium-oxygen batteries is greater than 10, where the N / P ratio is the ratio of the negative electrode capacity to the positive electrode capacity. The way to increase the negative electrode capacity is to increase the amount of lithium metal. However, both the catalyst and lithium metal are relatively expensive, so the cost of lithium-oxygen secondary batteries is high.
[0004] Furthermore, to give lithium-oxygen batteries a longer service life, that is, to increase the number of charging and discharging cycles of lithium-oxygen batteries, the capacitance of lithium-oxygen batteries will be limited to a relatively small value. When the current density of current lithium-oxygen batteries is 100 mA / g, the capacitance of lithium-oxygen batteries is only about 1000–2000 mAh / g. Summary of the Invention
[0005] One object of the present invention is to provide a primary lithium-oxygen battery.
[0006] The present invention provides a primary lithium-oxygen battery, which includes a positive electrode, a negative electrode, and a catalyst-free electrolyte disposed between the positive electrode and the negative electrode. The primary lithium-oxygen battery of the present invention uses a catalyst-free electrolyte and can reduce the amount of lithium metal at the negative electrode to lower the N / P ratio. Therefore, compared with current secondary lithium-oxygen batteries, the primary lithium-oxygen battery of the present invention has a lower cost. In addition, the primary lithium-oxygen battery of the present invention has a higher weight-specific energy density. Brief Description of the Drawings
[0007] Figure 1 A simple schematic diagram showing the primary lithium-oxygen battery of the present invention.
[0008] Figure 2Display Figure 1 The experimental results of the electrochemical test on the lithium-oxygen primary battery.
[0009] Explanation of reference numerals: 10 - lithium-oxygen primary battery; 12 - positive electrode; 14 - catalyst-free electrolyte; 16 - negative electrode. Detailed implementation mode
[0010] The present invention designs the lithium-oxygen battery, which was originally a secondary battery, into a primary battery to obtain a higher weight energy density. Therefore, the lithium-oxygen primary battery of the present invention can provide a much higher capacitance than the current lithium-oxygen secondary battery during a single discharge.
[0011] Figure 1 A simple schematic diagram showing the lithium-oxygen primary battery of the present invention. The lithium-oxygen primary battery of the present invention is similar to the current lithium-oxygen secondary battery. The difference is that no catalyst is added to the electrolyte of the lithium-oxygen primary battery of the present invention, and the amount of lithium metal in the negative electrode can be reduced. Since the lithium-oxygen primary battery of the present invention does not require a catalyst and can reduce the amount of lithium metal, the cost can be greatly reduced.
[0012] For convenience of description, Figure 1 Only a positive electrode 12 (or cathode), a catalyst-free electrolyte 14, and a negative electrode 16 (or anode) of the lithium-oxygen primary battery 10 are shown, and other parts of the lithium-oxygen primary battery 10 are not shown. The positive electrode 12 includes a porous conductive carbon material and a polymer adhesive, and the porous conductive carbon material includes, but is not limited to, carbon nanotubes. The negative electrode 16 includes lithium metal. The N / P ratio of the lithium-oxygen primary battery 10 is 1 - 2, but the present invention is not limited thereto. The catalyst-free electrolyte 14 is between the positive electrode 12 and the negative electrode 16. The catalyst-free electrolyte 14 includes, but is not limited to, a lithium salt and an ether solvent.
[0013] Figure 2 Display Figure 1 The experimental results of the electrochemical test on the lithium-oxygen primary battery, where the current density of the lithium-oxygen primary battery is 100 mA / g. From Figure 2 It can be seen that the capacitance of the lithium-oxygen primary battery 10 of the present invention is greater than 20000 mAh / g, far exceeding the capacitance of the current lithium-oxygen secondary battery (about 1000 - 2000 mAh / g). In other words, the weight energy density of the lithium-oxygen primary battery 10 of the present invention is much greater than that of the lithium-oxygen secondary battery.
[0014] There are many methods for fabricating the positive electrode 12 of the primary lithium-oxygen battery 10 of the present invention. The following presents one method for fabricating the positive electrode, but the present invention is not limited thereto. A porous conductive carbon material and a polymer binder are mixed at a weight ratio of 9:1 and placed in a container, and N-methyl-2-pyrrolidone (NMP) is added to make the powder weight percentage of the former two 25%. After the aforementioned slurry is sufficiently stirred for 1 hour, it is coated on a carbon paper using a coating gauge. Then, the carbon paper is placed in an oven and baked at 80°C for 1 hour to remove most of the NMP solvent. Finally, the baked carbon paper is placed in a vacuum oven and dried at 80°C overnight to obtain the positive electrode 12 of the primary lithium-oxygen battery 10.
[0015] In one embodiment, the method for fabricating the catalyst-free electrolyte 14 includes preparing an electrolyte with a concentration of 1 M of a lithium salt and an ether solvent in an anhydrous environment, where M is mole.
[0016] The above are only embodiments of the present invention and do not impose any formal restrictions on the present invention. Although the present invention has been provided above with embodiments, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field to which the present invention pertains, without departing from the scope of the technical solution of the present invention, may make some modifications or equivalents by using the technical content disclosed above. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.
Claims
1. A primary lithium-oxygen battery, characterized in that, Comprising: A positive electrode; A negative electrode; And A catalyst-free electrolyte disposed between the positive electrode and the negative electrode.
2. The primary lithium-oxygen battery according to claim 1, characterized in that, The positive electrode includes a porous conductive carbon material and a polymer binder.
3. The primary lithium-oxygen battery according to claim 2, wherein The porous conductive carbon material includes carbon nanotubes.
4. The primary lithium-oxygen battery according to claim 1, characterized in that, The negative electrode includes lithium metal.
5. The primary lithium-oxygen battery according to claim 1, wherein The catalyst-free electrolyte includes a lithium salt and an ether solvent.
6. The primary lithium-oxygen battery according to claim 1, characterized in that, The N / P ratio of the lithium-oxygen primary battery is 1–2.
7. The primary lithium-oxygen battery according to claim 1, characterized in that, The capacitance of the lithium-oxygen primary battery is greater than 20000 mAh / g.