Lithium ion battery gas getter

Abstract

The invention provides a lithium ion battery gas getter. The present disclosure relates to systems and methods for gas mitigation. In one aspect of the present disclosure, a battery is presented. The battery has a degassed lithium-rich manganese battery cell and a lithium-based anode encapsulated with a lithium-rich manganese cathode saturated in an electrolyte. A barium oxide-based coating is in the degassed lithium-rich manganese battery cell and is configured to convert oxygen and carbon dioxide to barium peroxide and carbonate and retain the barium peroxide and the carbonate.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to gas mitigation for lithium ion batteries. BACKGROUND

[0002] Lithium ion batteries (LIBs) generate gases during initial charging and operation maintenance at certain potentials. This gas generation can occur at both the cathode side and the anode side of the battery and is influenced by various factors. At the cathode, generation of gases such as oxygen and carbon dioxide is observed. Oxygen can be released from nickel manganese cobalt oxide (NMC) or lithium rich manganese (LMR) cathodes, contributing to gas generation. Additionally, gases can be generated through interactions between the cathode surface and the electrolyte. This phenomenon is more pronounced during the initial charge / discharge cycles of the battery, which are part of the cell formation and aging process. Although the rate of gas generation decreases after this stage, the rate of gas generation continues at a reduced level during cell storage and cycling, particularly at high states of charge (SOC). Factors such as incomplete phase transformation during cell formation, cathode material particle breakage, and exposure to extreme temperatures can lead to continued gas generation.

[0003] After the formation stage, the sealed LIBs to contain the internal components and electrolyte. Accumulation of gases within this sealed environment can lead to internal pressurization. This in turn can lead to an increase in cell resistance. In all cell types, internal pressurization can affect the wetting of the separator, potentially leading to dry spots and lithium plating. Gases generated within the cell, particularly carbon dioxide and oxygen, can also interact with other cell components in ways that alter battery performance. For example, oxygen can convert metal and anode materials, and carbon dioxide dissolved in the electrolyte can alter its viscosity, ionic conductivity, stability, and cause other issues. SUMMARY

[0004] In one aspect of the present disclosure, a battery is presented. The battery has a degassed lithium rich manganese battery cell having a lithium based anode packaged with a lithium rich manganese cathode saturated in electrolyte. A barium oxide based coating is in the degassed lithium rich manganese battery cell configured to convert oxygen and carbon dioxide gases to barium peroxide and carbonate and retain the barium peroxide and the carbonate. The battery can be a prismatic battery cell, a pouch battery cell, or a cylindrical battery cell. The polymer jacket can be fluorine containing polymer based.

[0005] In another aspect of the disclosure, a battery pack is presented. The battery includes a plurality of lithium-rich manganese battery cell assemblies defining a battery stack. A binary metal oxide-based coating with a polymeric sheath on an inner surface of the battery stack is configured to convert oxygen and carbon dioxide gases into binary metal peroxides and carbonates and encapsulate the binary metal peroxides and carbonates. The binary metal oxide-based coating can include an alkaline earth metal. The alkaline earth metal can be magnesium or barium. The polymeric sheath can be fluoropolymer-based. The plurality of lithium-rich manganese battery cell assemblies can be prismatic battery cells, cylindrical battery cells, or pouch battery cells.

[0006] In yet another aspect of the disclosure, a method of manufacturing is presented. The method includes encapsulating a lithium-based anode with a lithium-rich manganese cathode, saturating the lithium-based anode and the lithium-rich manganese cathode with an electrolyte to form a lithium-rich manganese battery cell, degassing the lithium-rich manganese battery cell to form a degassed lithium-rich manganese battery cell, and then applying a binary oxide-based coating to an inner surface of the degassed lithium-rich manganese battery cell. In some configurations, the method can include selecting low surface area particles of a binary oxide-based material prior to inserting the binary oxide-based material into the degassed lithium-rich manganese battery cell. In other configurations, degassing includes cooling the lithium-rich manganese battery cell. In further configurations, a polymeric sheath can be applied to the binary oxide-based coating. Optionally, the method can include sealing the degassed lithium-rich manganese battery cell. In some configurations, the binary oxide-based coating can be mixed with a solvent prior to application. BRIEF DESCRIPTION OF DRAWINGS

[0007] Figure 1 is a schematic of a battery pack in accordance with one or more embodiments of the disclosure;

[0008] Figure 2 is a schematic of a battery cell in accordance with one or more embodiments of the disclosure; and

[0009] Figure 3 is a flowchart of a method of manufacturing in accordance with one or more embodiments of the disclosure. DETAILED DESCRIPTION

[0010] Embodiments are described herein. It should be understood, however, that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale. Some features can be exaggerated to show details, while other features can be omitted. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but only as a representative basis for teaching one skilled in the art to various embodiments.

[0011] Various features referred to in relation to any one of the drawings can be combined with features shown in one or more other drawings to produce embodiments that are not explicitly shown or described. The combination of features shown provides representative embodiments for typical applications. However, various combinations and modifications of the features, consistent with the teachings of the present disclosure, can be desired for particular applications or implementations.

[0012] In developing LIBs, particularly LIBs with high NMC or LMR cathodes and other high voltage battery cells, managing the formation and accumulation of gases, such as oxygen and carbon dioxide, is one factor. NMC refers to a class of cathode materials that combine nickel, manganese, and cobalt in various ratios to achieve energy density balance. LMR cathodes, on the other hand, contain higher concentrations of lithium and manganese. These gases are byproducts of the battery cell formation process and can continue to accumulate during the working life of the battery, potentially impacting its performance and life.

[0013] During the LIB cell formation process, the interaction between the electrodes and the electrolyte results in the creation of a passivation layer on the anode, known as the solid-electrolyte interface (SEI), and on the cathode, known as the cathode-electrolyte interface (CEI). While these layers are necessary for the proper operation of the battery, preventing direct contact between the electrodes and the electrolyte, the formation process itself results in the generation of oxygen and carbon dioxide.

[0014] Gas getters in LIBs refer to materials that absorb or chemically react with gases generated during battery operation, such as oxygen and carbon dioxide. The materials can be metal oxides, and specifically alkaline earth metals. These getters maintain the integrity and performance of the battery by mitigating internal pressurization and chemical instability. Strategies are presented to optimize the performance and extend the life of these gas getters within battery cells. These strategies include applying an inert, low-porosity polymer layer to the getters, adding getters during or after the degassing step of the battery cell, or selecting getters with low surface area to slow down the reaction and saturation rates.

[0015] To address the presence of these gases within a sealed battery environment, the use of metal oxides as reagents capable of transforming carbon dioxide into carbonates through the reaction MO(s) + CO2(g) → MCO3(s) is explored. The effectiveness of these reactions is influenced by the properties of the metal oxides and the conditions within the battery cell, such as temperature and moisture content. Among these metal oxides, barium oxide stands out due to its ability to react with both carbon dioxide and oxygen, the latter reaction producing a stable peroxide BaO(s) + ½ O2(g) → BaO2(s).

[0016] The present disclosure outlines a method that combines a degassed lithium-rich manganese battery cell with a lithium-based anode and a lithium-rich manganese cathode immersed in an electrolyte. The battery cell has a barium oxide-based coating designed to facilitate the oxidation of oxygen and carbon dioxide into barium peroxide and carbonates, thereby sequestering these gases. The concept can be extended to a battery pack configuration that integrates multiple such battery cells, each utilizing this gas management strategy to potentially improve the overall performance and durability of the battery. This approach mitigates gas formation during the initial battery cell formation and degassing steps and also actively manages gas accumulation throughout the working life of the battery.

[0017] Reference is made to Figures 1 to 2 , Figure 1 A schematic of a battery pack 10 having a plurality of lithium-rich manganese battery cell assemblies 12 arranged to form a battery stack 14 is shown. The lithium-rich manganese battery cell assemblies 12 can be any suitable type of battery cell assembly, such as prismatic battery cells, cylindrical battery cells, or pouch battery cells. The battery pack 10 includes a binary metal oxide-based coating 16 on the inner surface of the battery stack 14. This coating 16 is developed to facilitate the conversion of oxygen and carbon dioxide gases into binary metal peroxides and carbonates. Following this conversion, the byproducts remain within the coating 16, thereby helping to maintain the internal environment of the battery cell, which in turn supports the life and performance of the battery.

[0018] The binary metal oxide-based coating 16 includes an alkaline earth metal. The alkaline earth metal for the binary metal oxide-based coating 16 can be magnesium, barium, or any other suitable alkaline earth metal. The binary metal oxide-based coating 16 has a polymer sheath 18. The polymer sheath 18 can be made of a fluoropolymer material for durability of the coating 16 and to moderate the interaction between the coating 16 and the internal gases.

[0019] In Figure 2In some embodiments, the method 26 can include cooling the lithium-rich manganese battery cell during the degassing. In other embodiments, the method 26 can further include applying a polymer sheath to the binary oxide-based coating. In some configurations, the method 26 further includes sealing the degassed lithium-rich manganese battery cell. In other configurations, the binary oxide-based coating can be mixed with a solvent prior to application.

[0020] Figure 3 is a flowchart of a manufacturing method 28 according to one or more embodiments of the present disclosure. The first block 30 involves packaging a lithium-based anode with a lithium-rich manganese cathode. Then, in block 32, which involves saturating the lithium-based anode and the lithium-rich manganese cathode with an electrolyte to form a lithium-rich manganese battery cell. In block 34, the lithium-rich manganese battery cell is degassed to form a degassed lithium-rich manganese battery cell. In block 36, which involves inserting a binary oxide-based material into the degassed lithium-rich manganese battery cell. In some configurations, the method 26 can include selecting low surface area particles of the binary oxide-based material prior to inserting the binary oxide-based material into the degassed lithium-rich manganese battery cell. Selecting the particles of the binary oxide-based material to have a low surface area prior to inserting the particles of the binary oxide-based material into the degassed lithium-rich manganese battery cell can mitigate saturation. The lower surface area particles exhibit a moderate reaction rate with the internal gases. By adjusting the surface area of these particles, the method 28 facilitates a stable interaction rate between the coating and the internal gases, such as oxygen and carbon dioxide. This stable interaction can prevent immediate saturation of the coating, thereby facilitating the continued efficacy and stability of the degassed lithium-rich manganese battery cell during its lifetime.

[0021] In some embodiments, the method 26 can include cooling the lithium-rich manganese battery cell during the degassing. In other embodiments, the method 26 can further include applying a polymer sheath to the binary oxide-based coating. In some configurations, the method 26 further includes sealing the degassed lithium-rich manganese battery cell. In other configurations, the binary oxide-based coating can be mixed with a solvent prior to application.

[0022] While the foregoing describes exemplary embodiments, these embodiments are not intended to describe all possible forms of the claims. The words used in the specification are words of description rather than limitation, and it is understood that various changes can be made without departing from the spirit and scope of the disclosure.

[0023] As previously described, features of various embodiments can be combined to form further embodiments of the present application not specifically described or illustrated. While various embodiments can have been described as providing advantages or being preferred over other embodiments or prior art implementations, one of ordinary skill in the art will recognize that one or more features or characteristics can be incorporated into one or more embodiments without degrading the overall system performance. These attributes can include, but are not limited to, strength, durability, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. As such, embodiments described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are within the scope of this disclosure and can be desirable for certain applications.

[0024] According to the present application, there is provided a battery having: a degassed lithium-rich manganese battery cell having a lithium-based anode packaged with a lithium-rich manganese cathode saturated in electrolyte; and a barium oxide-based coating in the degassed lithium-rich manganese battery cell, the barium oxide-based coating configured to convert oxygen and carbon dioxide into barium peroxide and carbonate and to retain the barium peroxide and the carbonate.

[0025] According to an embodiment, the degassed lithium-rich manganese battery cell is a prismatic battery cell.

[0026] According to an embodiment, the degassed lithium-rich manganese battery cell is a pouch battery cell.

[0027] According to an embodiment, the degassed lithium-rich manganese battery cell is a cylindrical battery cell.

[0028] According to an embodiment, the barium oxide-based coating includes a polymer sheath.

[0029] According to an embodiment, the polymer sheath is fluoropolymer-based.

[0030] According to the present invention, there is provided a battery pack having a plurality of lithium-rich manganese battery cell assemblies defining a battery stack, and a binary metal oxide-based coating having a polymeric sheath on an interior surface of the battery stack, the binary metal oxide-based coating configured to convert oxygen and carbon dioxide into binary metal peroxides and carbonates, and encapsulate the binary metal peroxides and the carbonates.

[0031] According to an embodiment, the binary metal oxide-based coating includes an alkaline earth metal.

[0032] According to an embodiment, the alkaline earth metal is magnesium.

[0033] According to an embodiment, the alkaline earth metal is barium.

[0034] According to an embodiment, the polymeric sheath is fluoropolymer-based.

[0035] According to an embodiment, the plurality of lithium-rich manganese battery cell assemblies are prismatic battery cells.

[0036] According to an embodiment, the plurality of lithium-rich manganese battery cell assemblies are cylindrical battery cells.

[0037] According to an embodiment, the plurality of lithium-rich manganese battery cell assemblies are pouch battery cells.

[0038] According to the present invention, a method includes encapsulating a lithium-based anode with a lithium-rich manganese cathode, saturating the lithium-based anode and the lithium-rich manganese cathode with an electrolyte to form a lithium-rich manganese battery cell, degassing the lithium-rich manganese battery cell to form a degassed lithium-rich manganese battery cell, and inserting a binary oxide-based material into the degassed lithium-rich manganese battery cell.

[0039] In one aspect of the present invention, the method includes selecting a low surface area particle of the binary oxide-based material prior to inserting the binary oxide-based material into the degassed lithium-rich manganese battery cell.

[0040] In one aspect of the present invention, the degassing includes cooling the lithium-rich manganese battery cell.

[0041] In one aspect of the present invention, the method includes applying a polymeric sheath to the binary oxide-based coating.

[0042] In one aspect of the present invention, the method includes sealing the degassed lithium-rich manganese battery cell.

[0043] In one aspect of the present invention, the binary oxide-based coating is mixed with a solvent prior to application.

Claims

1. A battery comprising: a degassed lithium-rich manganese battery cell having a lithium-based anode packaged with a lithium-rich manganese cathode saturated in an electrolyte; and a barium oxide-based coating in the degassed lithium-rich manganese battery cell, the barium oxide-based coating configured to convert oxygen and carbon dioxide into barium peroxide and carbonate and to retain the barium peroxide and the carbonate.

2. The battery of claim 1, wherein the degassed lithium-rich manganese battery cell is a prismatic battery cell.

3. The battery of claim 1, wherein the degassed lithium-rich manganese battery cell is a soft-pack battery cell.

4. The battery of claim 1, wherein the degassed lithium-rich manganese battery cell is a cylindrical battery cell.

5. The battery of claim 1, wherein the barium oxide-based coating comprises a polymer jacket.

6. The battery of claim 5, wherein the polymer jacket is fluoropolymer-based.

7. A battery pack comprising: a plurality of lithium-rich manganese battery cell assemblies defining a battery stack; and a binary metal oxide-based coating with a polymer jacket on an inner surface of the battery stack, the binary metal oxide-based coating configured to catalyze a reaction of oxygen and carbon dioxide into a binary metal peroxide and a carbonate and to package the binary metal peroxide and the carbonate.

8. The battery pack of claim 7, wherein the binary metal oxide-based coating comprises an alkaline earth metal.

9. The battery pack of claim 8, wherein the alkaline earth metal is magnesium.

10. The battery pack of claim 9, wherein the alkaline earth metal is barium.

11. The battery pack of claim 7, wherein the polymer jacket is fluoropolymer-based.

12. The battery pack of claim 7, wherein the plurality of lithium-rich manganese battery cell assemblies are prismatic battery cells.

13. The battery pack of claim 7, wherein the plurality of lithium-rich manganese battery cell assemblies are cylindrical battery cells.

14. The battery pack of claim 7, wherein the plurality of lithium-rich manganese battery cell assemblies are soft-pack battery cells.

15. A method comprising: packaging a lithium-based anode with a lithium-rich manganese cathode; saturating the lithium-based anode and the lithium-rich manganese cathode with an electrolyte to form a lithium-rich manganese battery cell; degassing the lithium-rich manganese battery cell to form a degassed lithium-rich manganese battery cell; and applying a binary oxide-based coating to an inner surface of the degassed lithium-rich manganese battery cell.

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