Thin film battery device and method of making a thin film battery device

Abstract

This application relates to a thin-film battery device and a method for fabricating the thin-film battery device. The thin-film battery device includes: a plurality of sub-cells connected in series, each sub-cell including: a first sub-cell portion; and a second sub-cell portion connected in parallel with the first sub-cell portion, wherein the second sub-cell portion is configured to have a reverse breakdown voltage greater than that of the first sub-cell portion. Using the solution of this embodiment, power loss can be reduced after some sub-cells are blocked and undergo reverse breakdown.

Description

Technical Field

[0001] This application relates to the field of photovoltaic technology, and in particular to a thin-film battery device and a method for preparing the thin-film battery device. Background Technology

[0002] With the rapid development of the new energy industry, thin-film battery devices, such as perovskite photovoltaic cells, have gradually been developed and applied. In related technologies, thin-film battery devices consist of all sub-cells connected in series. When a small number of sub-cells are severely shaded, the short-circuit current of the shaded cell will be less than the module's operating current. At this time, charge will not accumulate at the ends of that cell, meaning a forward bias cannot be formed. However, the remaining normal cells can accumulate charge, causing the shaded cell to be in a reverse bias state, thus leading to reverse breakdown of the shaded sub-cell. Depending on the duration of the breakdown, this causes varying degrees of permanent damage, resulting in significant power loss.

[0003] Therefore, there is a need to reduce the power loss of some sub-cells in thin-film battery devices after they are blocked and reverse-broken. Summary of the Invention

[0004] Therefore, it is necessary to provide a thin-film battery device and a method for preparing the thin-film battery device that can help reduce power loss after some sub-cells are blocked and reversed and broken down, in order to address the above-mentioned technical problems.

[0005] In a first aspect, this application provides a thin-film battery device, wherein the thin-film battery device includes: a plurality of sub-cells connected in series, each sub-cell comprising:

[0006] First sub-battery section;

[0007] A second sub-battery section connected in parallel with the first sub-battery section, wherein the second sub-battery section is configured to have a reverse breakdown voltage greater than that of the first sub-battery section.

[0008] Based on this embodiment, the thin-film battery device divides the sub-cells of the thin-film battery device into a first sub-cell portion and a second sub-cell portion, the difference in reverse breakdown voltage being greater than or equal to a first preset threshold. The first sub-cell portion and the second sub-cell portion are connected in parallel to each other, thereby forming a limiting structure. This ensures that when the reverse voltage at both ends of the sub-cell is high due to being blocked, only the area of ​​the first sub-cell portion with a lower reverse breakdown voltage will be broken down, while the area of ​​the second sub-cell portion with a higher reverse breakdown voltage will not be broken down. This allows the reverse breakdown current to be diverted from the broken first sub-cell portion and the unbroken second sub-cell portion, with the first sub-cell portion becoming the main path for the current. Thus, when reverse breakdown would cause destructive damage to the battery assembly, by sacrificing a portion of the sub-cell to protect other portions of the sub-cell, power loss can be reduced after some sub-cells are blocked and reverse-broken.

[0009] In some embodiments, the difference between the reverse breakdown voltage of the first sub-cell portion and the reverse breakdown voltage of the second sub-cell portion is greater than or equal to a first preset threshold.

[0010] Based on this embodiment, by limiting the difference between the reverse breakdown voltage of the first sub-cell portion and the reverse breakdown voltage of the second sub-cell portion to be greater than or equal to a first preset threshold, the difference is not too small, so that when reverse breakdown is blocked, only the first sub-cell portion is broken down and the second sub-cell portion is not broken down, which is more conducive to process implementation.

[0011] In some embodiments, the first sub-battery portion includes at least one film layer, the second sub-battery portion includes at least one film layer, and the thickness of the at least one film layer of the first sub-battery portion is less than the thickness of the at least one film layer of the second sub-battery portion.

[0012] Based on this embodiment, when the first sub-cell portion includes at least one film layer and the second sub-cell portion includes at least one film layer, by setting the thickness of at least one film layer of the first sub-cell portion to be less than the thickness of at least one film layer of the second sub-cell portion, since the greater the thickness of the film layer, the lower the possibility of reverse breakdown by current, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown characteristics.

[0013] In some embodiments, the at least one film layer includes at least one functional film layer, the thickness of one of the functional film layers of the first sub-battery portion is less than the thickness of one of the functional film layers of the second sub-battery portion, and the thickness of the other film layers of the first sub-battery portion is the same as the thickness of the other film layers of the second sub-battery portion.

[0014] Based on this embodiment, by setting the thickness of one functional film layer of the first sub-cell portion and the second sub-cell portion to be different, while setting the thickness of the other film layers of the first sub-cell portion and the second sub-cell portion to be the same, since the greater the thickness of the film layer, the lower the possibility of reverse breakdown by current, it is possible to make the first sub-cell portion and the second sub-cell portion have different reverse breakdown voltages. Furthermore, setting the thickness of only one functional film layer to be different is also more conducive to the realization of the process.

[0015] In some embodiments, the film material of at least one film layer of the first sub-battery portion is the same as the film material of at least one film layer of the second sub-battery portion.

[0016] Based on this embodiment, since different film materials typically have different reverse breakdown voltage characteristics, when the film material of at least one film layer in the first sub-cell portion is the same as the film material of at least one film layer in the second sub-cell portion, it is more advantageous to realize the process by setting the thickness of the same functional film layer in the first sub-cell portion and the second sub-cell portion to be different, while setting the thickness of other film layers in the first sub-cell portion and the second sub-cell to be the same.

[0017] In some embodiments, the difference between the thickness of at least one film layer of the first sub-battery portion and the thickness of at least one film layer of the second sub-battery portion is greater than or equal to a second preset threshold.

[0018] Based on this embodiment, by limiting the difference between the thickness of at least one film layer of the first sub-cell portion and the thickness of at least one film layer of the second sub-cell portion to be greater than or equal to a second preset threshold, the difference in thickness is not too small, so that when the reverse breakdown is blocked, only the first sub-cell portion is broken down, and the second sub-cell portion is not broken down, which is more conducive to the implementation of the process.

[0019] In some embodiments, the first sub-battery portion includes at least one film layer, the second sub-battery portion includes at least one film layer, and the film layer material of the at least one film layer of the first sub-battery portion is different from the film layer material of the at least one film layer of the second sub-battery portion.

[0020] Based on this embodiment, when the first sub-cell portion includes at least one film layer and the second sub-cell portion includes at least one film layer, by setting the film layer material of at least one film layer of the first sub-cell portion to be different from the film layer material of at least one film layer of the second sub-cell portion, since different film layer materials usually have different reverse breakdown voltage characteristics, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown characteristics by selecting the film layer material.

[0021] In some embodiments, the at least one film layer includes at least one functional film layer, wherein the film material of one of the functional film layers of the first sub-battery portion is different from the film material of the one of the functional film layers of the second sub-battery portion, and the materials of the other film layers of the first sub-battery portion are the same as the materials of the other film layers of the second sub-battery portion.

[0022] Based on this embodiment, by setting the film material of one of the functional films in the first sub-cell portion and the second sub-cell portion to be different, while setting the film material of the other films in the first sub-cell portion and the second sub-cell portion to be the same, since different film materials typically have different reverse breakdown voltage characteristics, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown voltages. Furthermore, setting the film material of only one functional film layer to be different is also more conducive to process implementation.

[0023] In some embodiments, one of the functional membrane layers includes a passivation layer and / or a hole transport layer.

[0024] By setting different thicknesses for the passivation layer and / or hole transport layer of the first sub-cell portion and the second sub-cell portion, or by using different film materials, different passivation properties and / or hole transport properties can be exhibited. Based on the different passivation properties and / or hole transport properties, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown characteristics, thereby enabling the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0025] In some embodiments, the first sub-battery portion includes at least one film layer, the second sub-battery portion includes at least one film layer, and the number of film layers in the second sub-battery portion is greater than the number of film layers in the first sub-battery portion.

[0026] Based on this embodiment, both the first sub-cell portion and the second sub-cell portion may include at least one film layer. The number of film layers in the second sub-cell portion is greater than the number of film layers in the first sub-cell portion. Since different film layers typically require a certain current to be broken down, the second sub-cell portion with more film layers usually has higher reverse breakdown characteristics and is less prone to breakdown than the first sub-cell portion with fewer film layers. This allows the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0027] In some embodiments, the first sub-cell portion includes N film layers, and the second sub-cell portion includes the N film layers and a first passivation layer.

[0028] Based on this embodiment, in addition to the fact that both the first sub-cell portion and the second sub-cell portion have N film layers, the second sub-cell portion further includes a first passivation layer. Since the passivation layer is a film layer that can reduce charge recombination loss, the second sub-cell portion with the added first passivation layer is less likely to be reverse-broken down than the first sub-cell portion, thereby enabling the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0029] In some embodiments, the N film layers include at least a hole transport layer, a photovoltaic layer, an electron transport layer, and an electrode layer arranged sequentially, wherein;

[0030] The first passivation layer is disposed between the electron transport layer and the electrode layer;

[0031] and / or

[0032] The first passivation layer is disposed between the hole transport layer and the photovoltaic layer.

[0033] Based on this embodiment, in the second sub-cell portion of the sub-cell, a first passivation layer can be disposed between the electron transport layer and the electrode layer, thereby passivating the boundary interface between the electron transport layer and the electrode layer. Alternatively, the first passivation layer can be disposed between the hole transport layer and the photovoltaic layer, thereby passivating the boundary interface between the hole transport layer and the photovoltaic layer. Alternatively, a first passivation layer can be disposed between the electron transport layer and the electrode layer, and between the hole transport layer and the photovoltaic layer, respectively, to simultaneously passivate the boundary interfaces between the electron transport layer and the electrode layer, and between the hole transport layer and the photovoltaic layer. Based on this, the second sub-cell portion is less susceptible to reverse breakdown compared to the first sub-cell portion.

[0034] In some embodiments, the N film layers further include a second passivation layer disposed between the hole transport layer and the photovoltaic layer, and / or a second passivation layer disposed between the electron transport layer and the electrode layer.

[0035] Based on this embodiment, among the N film layers provided in both the first and second sub-cell portions of the sub-cell, a second passivation layer can also be provided between the hole transport layer and the photovoltaic layer, or between the electron transport layer and the electrode layer. Furthermore, a second passivation layer can be provided between the hole transport layer and the photovoltaic layer, and also between the electron transport layer and the electrode layer. Thus, by providing multiple passivation layers, the performance of the cell can be further improved.

[0036] In some embodiments, the first passivation layer and / or the second passivation layer includes a hole blocking layer.

[0037] In some embodiments, the first sub-battery portion includes a plurality of first sub-battery portions, and each first sub-battery portion is arranged in parallel.

[0038] Based on this embodiment, by setting multiple first sub-cell sections and connecting them in parallel, the reverse breakdown current can flow through multiple first sub-cell sections, which is more conducive to heat dissipation. On this basis, the heat dissipation performance and safety performance of the thin-film battery device can be improved.

[0039] In some embodiments, the reverse breakdown voltages of each of the first sub-cell portions may be the same or different.

[0040] Based on this embodiment, when multiple first sub-cell portions are provided, the reverse breakdown voltages of the multiple first sub-cell portions can be the same or different, thereby reducing the requirement for consistency of each first sub-cell portion and facilitating the realization of a sub-cell including a first sub-cell portion and a second sub-cell portion.

[0041] In some embodiments, the first sub-cell portion and / or the second sub-cell portion includes a perovskite film layer.

[0042] Based on this embodiment, the first sub-cell portion and / or the second sub-cell portion of the sub-cell include a perovskite film layer, thereby realizing a perovskite cell. Since perovskite photovoltaic cells have extremely high theoretical conversion efficiency, for thin-film battery devices with high conversion efficiency, it is also possible to reduce power loss after some sub-cells are blocked and reverse-broken. It is possible to reduce power loss after being blocked and reverse-broken while maintaining high conversion efficiency.

[0043] In some embodiments, the first preset threshold is greater than or equal to 0.5V.

[0044] Based on this embodiment, by limiting the difference between the reverse breakdown voltage of the first sub-cell portion and the reverse breakdown voltage of the second sub-cell portion to greater than or equal to 0.5V, the difference is not too small, so that when the reverse breakdown is blocked, only the first sub-cell portion is broken down, and the second sub-cell portion is not broken down, which is more conducive to the realization of the process.

[0045] In some embodiments, the first preset threshold includes 1V.

[0046] In some embodiments, both the first sub-battery portion and the second sub-battery portion include M film layers. The arrangement order and function of the M film layers in the first sub-battery portion and the second sub-battery portion are the same. The difference between the thickness of one film layer in the first sub-battery portion and the thickness of one film layer in the second sub-battery portion is greater than or equal to a second preset threshold. The thickness of the other film layers in the first sub-battery portion is the same as the thickness of the other film layers in the second sub-battery portion.

[0047] Based on this embodiment, by setting the first sub-cell portion and the second sub-cell portion to have the same number of film layers, the same arrangement order, and the same film layer function, and only the difference in thickness on one of the functional film layers is greater than or equal to a second preset threshold, it is more conducive to process design and implementation.

[0048] In some embodiments, the difference between the reverse breakdown voltage of the first sub-battery portion and the reverse breakdown voltage of the second sub-battery portion is greater than or equal to the first preset threshold and less than or equal to the third preset threshold.

[0049] Based on this embodiment, by limiting the difference between the reverse breakdown voltage of the first sub-cell portion and the reverse breakdown voltage of the second sub-cell portion to a range between a first preset threshold and a third preset threshold, the difference is neither too small nor too large, so that when the reverse breakdown is blocked, only the first sub-cell portion is broken down, and the second sub-cell portion is not broken down, which is more conducive to the implementation of the process.

[0050] In some embodiments, the ratio of the area of ​​the first sub-battery portion to the area of ​​the sub-battery is greater than a preset ratio.

[0051] Based on this embodiment, by setting the area of ​​the first sub-battery portion to be larger than the area of ​​the sub-battery by a preset ratio, when the sub-battery is blocked and reversely broken down, most of the current flows through the broken first sub-battery portion, reducing the possibility of the sub-battery burning out due to excessively high energy density caused by the small area of ​​the first sub-battery portion.

[0052] In some embodiments, the preset ratio includes 5%.

[0053] In some embodiments, the second preset threshold is greater than or equal to 5 nanometers.

[0054] In some embodiments, the second preset threshold includes 10 nanometers.

[0055] Secondly, embodiments of this application provide a method for preparing a thin-film battery device, comprising the following steps:

[0056] The substrate in the first region is coated to form the first sub-cell portion of the sub-cell;

[0057] The substrate in the second region is coated to form the second sub-cell portion of the sub-cell, and the reverse breakdown voltage of the second sub-cell portion is greater than the reverse breakdown voltage of the first sub-cell portion, and the second sub-cell portion is connected in parallel with the first sub-cell portion.

[0058] Multiple sub-cells are connected in series to form a thin-film battery device.

[0059] The method for fabricating a thin-film battery device based on this embodiment involves coating a first region portion of the substrate and a second region portion of the substrate to form a first sub-cell portion and a second sub-cell portion of the sub-cell, respectively. Multiple sub-cells are then connected in series to form the thin-film battery device. Each sub-cell includes a first sub-cell portion and a second sub-cell portion, where the difference in reverse breakdown voltage is greater than or equal to a first preset threshold. The first and second sub-cell portions are connected in parallel to form a limiting structure. In this thin-film battery device, when the reverse voltage across the shielded sub-cell is very high, only the region of the first sub-cell portion with a lower reverse breakdown voltage will be broken down, while the region of the second sub-cell portion with a higher reverse breakdown voltage will not be broken down. This allows the reverse breakdown current to be diverted from the broken first sub-cell portion and the unbroken second sub-cell portion, with the first sub-cell portion becoming the main current path. Therefore, when reverse breakdown would cause destructive damage to the battery assembly, the power loss can be reduced after some sub-cells are shielded and reverse-broken by sacrificing a portion of the sub-cell.

[0060] In some embodiments, the first sub-battery portion includes at least one film layer, and the second sub-battery portion includes at least one film layer;

[0061] The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes:

[0062] The first region portion of the substrate is coated with a first coating amount to form the first sub-cell portion, and the second region portion of the substrate is coated with a second coating amount to form the second sub-cell portion, wherein the second coating amount is greater than the first coating amount.

[0063] Based on this embodiment, different coating amounts can be used to coat the first region portion of the substrate and the second region portion of the substrate respectively. Due to the different coating amounts, the thickness of the film layer formed on the first region portion of the substrate and the second region portion of the substrate is different, so that the thickness of at least one film layer of the corresponding first sub-cell portion is different from the thickness of at least one film layer of the second sub-cell portion. Since the greater the thickness of the film layer, the lower the possibility of reverse breakdown by current, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown characteristics.

[0064] In some embodiments, the at least one membrane layer includes at least one functional membrane layer and at least one other membrane layer;

[0065] The amount of one functional film layer applied to the first region of the substrate is less than the amount of the second functional film layer applied to the second region of the substrate.

[0066] The amount of other film layers applied to the first region of the substrate is the same as the amount of other film layers applied to the second region of the substrate.

[0067] Based on this embodiment, the coating amount of the first region portion of the substrate differs only when coating one functional film layer, while the coating amount of other film layers is the same. This results in only one functional film layer having a different thickness. Since the greater the film layer thickness, the lower the probability of reverse breakdown by current, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown voltages. Furthermore, by differentiating the coating amount of only one functional film layer, the thickness of the functional film layer in the first sub-cell portion and the second sub-cell portion formed on this basis will be different, which is also more conducive to the realization of the process.

[0068] In some embodiments, the difference between the first coating amount and the second coating amount is greater than a preset coating amount threshold.

[0069] Based on this embodiment, by limiting the difference between the first coating amount and the second coating amount to be greater than or equal to a preset coating amount threshold, the difference in coating amount will not be too small. In this technology, the difference in thickness will not be too small, so that when the reverse breakdown is blocked, only the first sub-cell part is broken down, and the second sub-cell part is not broken down, which is more conducive to the realization of the process.

[0070] In some embodiments, the first sub-battery portion includes at least one film layer, and the second sub-battery portion includes at least one film layer;

[0071] The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes:

[0072] The substrate in the first region is coated for a first duration to form the first sub-cell portion, and the substrate in the second region is coated for a second duration to form the second sub-cell portion, wherein the second duration is longer than the first duration.

[0073] Based on this embodiment, different coating durations can be applied to the first and second sub-substrates. Due to the different coating durations, the thickness of the film layer formed on the first and second sub-substrates is different, resulting in at least one film layer thickness of the corresponding first sub-cell portion being different from at least one film layer thickness of the second sub-cell portion. Since the greater the film layer thickness, the lower the possibility of reverse breakdown by current, the first and second sub-cell portions can have different reverse breakdown characteristics.

[0074] In some embodiments, the at least one membrane layer includes at least one functional membrane layer and at least one other membrane layer; the method further includes:

[0075] The time for coating one of the functional films on the first region of the substrate is less than the time for coating the one of the functional films on the second region of the substrate.

[0076] The time taken to coat other film layers on the first region of the substrate is the same as the time taken to coat other film layers on the second region of the substrate.

[0077] Based on this embodiment, the coating time for the first region portion of the substrate and the first region portion of the substrate differs only when coating one of the functional film layers, while the coating time for other film layers is the same. This results in only one functional film layer having a different thickness. Since the greater the film layer thickness, the lower the possibility of reverse breakdown by current, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown voltages. Furthermore, by differentiating the coating time for only one functional film layer, the thickness of the functional film layer in the first sub-cell portion and the second sub-cell portion formed on this basis will be different, which is also more conducive to the realization of the process.

[0078] In some embodiments, the first sub-battery portion includes at least one film layer, and the second sub-battery portion includes at least one film layer;

[0079] The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes:

[0080] A first film material is coated onto a portion of the substrate in the first region to form the first sub-cell portion, and a second film material is coated onto a portion of the substrate in the second region to form the second sub-cell portion. The first film material and the second film material are different.

[0081] Based on this embodiment, different film materials are used when coating the first region portion of the substrate and the second region portion of the substrate. Since different film materials usually have different reverse breakdown voltage characteristics, the first sub-cell portion and the second sub-cell portion formed on this basis can have different reverse breakdown characteristics by selecting the film material.

[0082] In some embodiments, the at least one membrane layer includes at least one functional membrane layer and at least one other membrane layer, and the method further includes:

[0083] A first functional film material is coated onto a portion of the substrate in the first region to form one of the functional film layers of the first sub-battery portion; and a second functional film material is coated onto a portion of the substrate in the second region to form one of the functional film layers of the second sub-battery portion, wherein the first functional film material and the second film material have different functions.

[0084] A third film material is applied to a portion of the substrate in the first region to form other film layers for the first sub-cell portion, and the third film material is applied to a portion of the substrate in the second region to form other film layers for the second sub-cell portion.

[0085] Based on this embodiment, when coating the first and second regional substrates, a different functional film material is used only for coating one of the functional film layers, while the other film layers use the same film material. Since different film materials typically have different reverse breakdown voltage characteristics, the first and second sub-cell portions formed on this basis can have different reverse breakdown voltages. Furthermore, using a different functional film material for only one functional film layer is more conducive to process implementation.

[0086] In some embodiments, one of the functional membrane layers includes a passivation layer and / or a hole transport layer.

[0087] Based on this embodiment, when using the first region portion of the substrate and the second region portion of the substrate, by setting different coating amounts and coating durations for the passivation layer and / or hole transport layer, or by using different functional film layer materials, different passivation properties and / or hole transport properties can be exhibited. Based on the different passivation properties and / or hole transport properties, the first sub-cell portion and the second sub-cell portion formed on this basis can have different reverse breakdown characteristics, thereby enabling the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0088] In some embodiments, the first sub-battery portion includes at least one film layer, and the second sub-battery portion includes at least one film layer;

[0089] The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the first sub-cell portion, includes:

[0090] A first number of film layers are coated on a portion of the substrate in the first region to form the first sub-cell portion, and a second number of film layers are coated on a portion of the substrate in the second region to form the second sub-cell portion, wherein the second number is greater than the first number.

[0091] Based on this embodiment, when coating the first region portion of the substrate and the second region portion of the substrate, more film layers are coated on the second region portion of the substrate. On this basis, a first sub-cell portion and a second sub-cell portion with different film layer numbers can be formed. Since different film layers usually require a certain current to be broken down, the second sub-cell portion with more film layer numbers usually has higher reverse breakdown characteristics and is less likely to be broken down than the first sub-cell portion with fewer film layer numbers. Thus, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown voltages.

[0092] In some embodiments, the second plurality of film layers includes the first plurality of film layers and the first passivation layer.

[0093] Based on this embodiment, in addition to having a first number of film layers, the first sub-cell portion and the second sub-cell portion formed by coating the first region portion substrate and the second region portion substrate further include a first passivation layer. Since the passivation layer is a film layer that can reduce charge recombination loss, the second sub-cell portion with the added first passivation layer is less likely to be reverse broken down compared to the first sub-cell portion, thereby enabling the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0094] In some embodiments, the ratio of the area of ​​the first region portion of the substrate to the area of ​​the substrate including the first region portion of the substrate and the second region portion of the substrate is greater than a preset ratio.

[0095] Based on this embodiment, by setting the area of ​​the first region portion of the substrate to be larger than the area of ​​the substrate including the first region portion of the substrate and the second region portion of the substrate by a preset ratio, and then forming the sub-cell on this basis, the area of ​​the first sub-cell portion is set to be larger than the area of ​​the sub-cell by a preset ratio. This allows most of the current to flow through the first sub-cell portion that is broken down when the sub-cell is blocked, thus reducing the possibility of the sub-cell burning out due to excessively high energy density caused by the small area of ​​the first sub-cell portion.

[0096] In some embodiments, the preset ratio includes 5%.

[0097] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description

[0098] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiments below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0099] Figure 1 This is a partial electrical schematic diagram of a thin-film battery device in one embodiment;

[0100] Figure 2 This is a schematic diagram of the film structure of the first sub-cell portion and the second sub-cell portion in one embodiment;

[0101] Figure 3 This is a schematic diagram of the film structure of the first sub-cell portion and the second sub-cell portion in another embodiment;

[0102] Figure 4 This is a top view of the position of the first sub-cell portion within the sub-cell in one embodiment;

[0103] Figure 5 This is a schematic diagram of the equivalent single-diode circuit model of a single sub-cell in one embodiment;

[0104] Figure 6 This is a structural block diagram of a battery module cycle aging test system in one embodiment;

[0105] Figure 7 This is an electrical schematic diagram of one of the sub-batteries being shielded in one embodiment;

[0106] Figure 8 This is a schematic flowchart illustrating the fabrication method of a thin-film battery device in a specific example.

[0107] Figure 9 This is a schematic flowchart illustrating the fabrication method of a thin-film battery device in a specific example.

[0108] Figure 10 This is a schematic diagram of the fabrication process of a thin-film battery device in another specific example;

[0109] Figure 11 This is a schematic diagram of the fabrication process of a thin-film battery device in another specific example. Detailed Implementation

[0110] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0111] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0112] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0113] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0114] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0115] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0116] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple groups" refers to two or more (including two groups), and "multiple pieces" refers to two or more (including two pieces).

[0117] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical term "connection" and other such terms should be interpreted broadly. For example, it can refer to a mechanical connection or an electrical connection; it can refer to a direct connection or an indirect connection through an intermediate medium; it can refer to the internal connection of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0118] Currently, the problem of reverse breakdown of a small number of sub-cells in thin-film battery devices after being blocked can cause varying degrees of permanent damage and significant power loss. The common approach is to reduce the risk of reverse breakdown by increasing the area of ​​the thin-film battery device or by modifying the circuit design. However, even when reverse breakdown of a sub-cell occurs, there is still a significant power loss, which is detrimental to the performance maintenance of the thin-film battery device.

[0119] To address this issue, one approach is to reduce the possibility of reverse breakdown by connecting a diode in antiparallel across multiple sub-cells connected in parallel. However, thin-film battery devices typically have a large number of sub-cells connected in series, and the reverse breakdown voltage (Vbr) of a single sub-cell is currently low. Therefore, regardless of whether there is an antiparallel bypass diode, the reverse bias voltage across the shaded sub-cell is sufficient to cause reverse breakdown, resulting in varying degrees of permanent damage depending on the duration of the breakdown.

[0120] Research has shown that when a sub-cell is blocked, the reverse bias voltage across its terminals becomes too high, which can cause the blocked sub-cell to break down. If the sub-cell is divided into two parts connected in parallel, and these two parts have different reverse breakdown characteristics, i.e., different reverse breakdown voltages, thus forming a limiting structure, then when the sub-cell is blocked, the reverse bias voltage will only break down the part with the smaller reverse breakdown voltage, while the part with the larger reverse breakdown voltage can be preserved. This can reduce the power loss caused by the blocking of sub-cells in thin-film battery devices.

[0121] Accordingly, embodiments of this application provide a thin-film battery device, wherein, combined with Figure 1 As shown, the thin-film battery device 1000 includes: a plurality of sub-cells 10 connected in series, each sub-cell 10 including:

[0122] First sub-battery section 101;

[0123] A second sub-battery section 102 is connected in parallel with the first sub-battery section 101, and the second sub-battery section 102 is configured to have a reverse breakdown voltage greater than that of the first sub-battery section 101.

[0124] In the thin-film battery device 1000, only some of the multiple sub-cells 10 may include a first sub-cell portion 101 and a second sub-cell portion 102 connected in series, thereby reducing power loss when these sub-cells 10 are reverse-biased due to obstruction. Alternatively, each sub-cell 10 may include a first sub-cell portion 101 and a second sub-cell portion 102 connected in series, thereby reducing power loss regardless of which sub-cell 10 is reverse-biased due to obstruction, which helps maintain the performance of the thin-film battery device. Therefore, in the embodiments of this application, an example is provided where each sub-cell 10 includes a first sub-cell portion 101 and a second sub-cell portion 102 connected in series.

[0125] The reverse breakdown voltage of the first sub-cell section 101 is the voltage across the first sub-cell section when the first sub-cell section 101 is reverse-biased. When the reverse bias voltage across the first sub-cell section 101 reaches this voltage, the first sub-cell section 101 will break down.

[0126] The reverse breakdown voltage of the second sub-cell section 102 is the voltage across the second sub-cell section when the second sub-cell section 102 is reverse-biased. When the reverse bias voltage across the second sub-cell section 102 reaches this voltage, the second sub-cell section 102 will break down.

[0127] Based on this, when one sub-cell is blocked, the bias voltage across the blocked sub-cell will first reach the first sub-cell section 101 with the lower reverse breakdown voltage, thus breaking down the first sub-cell section 101. This causes the reverse breakdown current to flow only through the broken-down first sub-cell section, significantly reducing the bias voltage across the blocked sub-cell and preventing further breakdown of the second sub-cell section. This prevents all sub-cells 10 from being broken down, thereby reducing the power loss caused by sub-cell breakdown. After the blockage is removed, the reverse breakdown only results in a small voltage loss in the sub-cell, further reducing this loss. Compared to the complete breakdown of the sub-cell, this increases the sub-cell's power output.

[0128] Based on this embodiment, the thin-film battery device divides the sub-cells of the thin-film battery device into a first sub-cell portion and a second sub-cell portion, the difference in reverse breakdown voltage being greater than or equal to a first preset threshold. The first sub-cell portion and the second sub-cell portion are connected in parallel to each other, thereby forming a limiting structure. This ensures that when the reverse voltage at both ends of the sub-cell is high due to being blocked, only the area of ​​the first sub-cell portion with a lower reverse breakdown voltage will be broken down, while the area of ​​the second sub-cell portion with a higher reverse breakdown voltage will not be broken down. This allows the reverse breakdown current to be diverted from the broken first sub-cell portion and the unbroken second sub-cell portion, with the first sub-cell portion becoming the main path for the current. Thus, when reverse breakdown would cause destructive damage to the battery assembly, by sacrificing a portion of the sub-cell to protect other portions of the sub-cell, power loss can be reduced after some sub-cells are blocked and reverse-broken.

[0129] In some embodiments, the difference between the reverse breakdown voltage of the first sub-battery portion 101 and the reverse breakdown voltage of the second sub-battery portion 102 is greater than or equal to a first preset threshold.

[0130] Based on this embodiment, by limiting the difference between the reverse breakdown voltage of the first sub-cell portion and the reverse breakdown voltage of the second sub-cell portion to be greater than or equal to a first preset threshold, the difference is not too small, so that when reverse breakdown is blocked, only the first sub-cell portion is broken down and the second sub-cell portion is not broken down, which is more conducive to process implementation.

[0131] There is more than one way to achieve different reverse breakdown voltages between the first sub-cell and the second sub-cell. The following will explain several of these methods.

[0132] In some embodiments, the first sub-battery portion includes at least one film layer, the second sub-battery portion includes at least one film layer, and the thickness of the at least one film layer of the first sub-battery portion is less than the thickness of the at least one film layer of the second sub-battery portion.

[0133] Film layers are different layers contained in the structure of thin-film batteries. Each film layer can perform different functions, such as electron transport layer, photovoltaic layer, hole transport layer, etc., but is not limited to these.

[0134] Based on this embodiment, when the first sub-cell portion includes at least one film layer and the second sub-cell portion includes at least one film layer, by setting the thickness of at least one film layer of the first sub-cell portion to be less than the thickness of at least one film layer of the second sub-cell portion, since the greater the thickness of the film layer, the lower the possibility of reverse breakdown by current, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown characteristics.

[0135] Wherein, the thickness of at least one film layer of the first sub-battery portion is less than the thickness of at least one film layer of the second sub-battery portion, meaning that the overall thickness of the film layers of the first sub-battery portion is less than the overall thickness of the second sub-battery portion. This application does not limit the relationship between the thicknesses of the various film layers, as long as the overall thickness of the film layers of the first sub-battery portion is less than the overall thickness of the second sub-battery portion.

[0136] The method for ensuring that the thickness of at least one film layer in the first sub-cell portion is less than the thickness of at least one film layer in the second sub-cell portion is not limited. It can be that the thickness of each film layer in the first sub-cell portion and the thickness of each film layer in the second sub-cell portion are set separately, so that the thickness of at least one film layer in the first sub-cell portion is less than the thickness of at least one film layer in the second sub-cell portion. Alternatively, the thickness of some film layers in the first sub-cell portion can be set to be the same as the thickness of some film layers in the second sub-cell portion, while only setting the thickness of some film layers in the first and second sub-cell portions to be different, so that the overall thickness of the film layers in the first sub-cell portion is less than the overall thickness of the second sub-cell portion, which is more conducive to battery manufacturing processes.

[0137] Accordingly, in some embodiments, at least one film layer includes at least one functional film layer and at least one other film layer, wherein the thickness of one of the functional film layers of the first sub-battery portion is less than the thickness of the one of the functional film layers of the second sub-battery portion, and the thickness of the other film layers of the first sub-battery portion is the same as the thickness of the other film layers of the second sub-battery portion.

[0138] Among them, functional film layers are film layers with special functions, such as electron transport layers with electron transport functions, passivation layers with passivation functions, etc., but are not limited to these.

[0139] Based on this embodiment, by setting the thickness of one functional film layer of the first sub-cell portion and the second sub-cell portion to be different, while setting the thickness of the other film layers of the first sub-cell portion and the second sub-cell portion to be the same, since the greater the thickness of the film layer, the lower the possibility of reverse breakdown by current, it is possible to make the first sub-cell portion and the second sub-cell portion have different reverse breakdown voltages. Furthermore, setting the thickness of only one functional film layer to be different is also more conducive to the realization of the process.

[0140] In this configuration, if the thickness of one functional film layer in the first sub-cell section is less than the thickness of that functional film layer in the second sub-cell section, while the thicknesses of the other film layers are the same, the film materials of the film layers in the first sub-cell section and the film materials of the film layers in the second sub-cell section can also be set differently, for example, they can be set to be the same or different. The goal is to ensure that the first sub-cell section and the second sub-cell section have different reverse breakdown voltages.

[0141] Based on this, in some embodiments, the film material of at least one film layer of the first sub-battery portion is the same as the film material of at least one film layer of the second sub-battery portion.

[0142] Based on this embodiment, since different film materials typically have different reverse breakdown voltage characteristics, when the film material of at least one film layer in the first sub-cell portion is the same as the film material of at least one film layer in the second sub-cell portion, it is more advantageous to realize the process by setting the thickness of the same functional film layer in the first sub-cell portion and the second sub-cell portion to be different, while setting the thickness of other film layers in the first sub-cell portion and the second sub-cell to be the same.

[0143] In some embodiments, the difference between the thickness of at least one film layer of the first sub-battery portion and the thickness of at least one film layer of the second sub-battery portion is greater than or equal to a second preset threshold.

[0144] Wherein, the difference between the thickness of at least one film layer of the first sub-battery portion and the thickness of at least one film layer of the second sub-battery portion is greater than or equal to a second preset threshold. This can be the difference between the overall thickness of each film layer of the first sub-battery portion and the overall thickness of each film layer of the second sub-battery portion being greater than or equal to the second preset threshold. In the case where the thickness of one of the functional film layers is different as described above, while the thickness of the other film layers is the same, it can also be the difference between the thickness of this one functional film layer of the first sub-battery portion and the second sub-battery portion being greater than or equal to the second preset threshold.

[0145] Based on this embodiment, by limiting the difference between the thickness of at least one film layer of the first sub-cell portion and the thickness of at least one film layer of the second sub-cell portion to be greater than or equal to a second preset threshold, the difference in thickness is not too small, so that when the reverse breakdown is blocked, only the first sub-cell portion is broken down, and the second sub-cell portion is not broken down, which is more conducive to the implementation of the process.

[0146] The multiple film layers included in the first sub-cell portion may be the same as or different from the multiple film layers included in the second sub-cell portion. Taking the example that the number of at least one film layer included in the first sub-cell portion and the number of at least one film layer included in the second sub-cell portion are the same, the film layer structures of the first and second sub-cell portions in a specific example can be as follows: Figure 2 As shown.

[0147] by Figure 2 As shown in the example, the first sub-cell and the second sub-cell have the same function and the same film material, but different thicknesses. These films can be, for example, as shown in the example. Figure 2 Any of the films shown, such as a TCO layer, hole transport layer, photovoltaic layer, electron transport layer, etc. In specific examples, it could be that only one functional film layer has the same film material, but the film thickness of the second sub-cell portion is greater than that of the first sub-cell portion; or it could be that multiple functional films have the same film material, but the film thickness of the second sub-cell portion is greater than that of the first sub-cell portion. This can be determined based on actual needs.

[0148] In some embodiments, the difference in reverse breakdown voltage between the first sub-cell and the second sub-cell can also be achieved through the difference in the film material.

[0149] Accordingly, in some embodiments, the first sub-battery portion includes at least one film layer, the second sub-battery portion includes at least one film layer, and the film layer material of the at least one film layer of the first sub-battery portion is different from the film layer material of the at least one film layer of the second sub-battery portion.

[0150] Based on this embodiment, when the first sub-cell portion includes at least one film layer and the second sub-cell portion includes at least one film layer, by setting the film layer material of at least one film layer of the first sub-cell portion to be different from the film layer material of at least one film layer of the second sub-cell portion, since different film layer materials usually have different reverse breakdown voltage characteristics, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown characteristics by selecting the film layer material.

[0151] The method in which the film material of at least one film layer in the first sub-cell portion differs from the film material of at least one film layer in the second sub-cell portion is not limited. It may be that the film materials of each film layer in the first sub-cell portion are all different from the film materials of each film layer in the second sub-cell portion, so that the reverse breakdown voltage of the first sub-cell portion is lower than the reverse breakdown voltage of the second sub-cell portion. Alternatively, the film materials of some film layers in the first sub-cell portion may be the same as the film materials of some film layers in the second sub-cell portion, while only the film materials of some film layers in the first and second sub-cell portions are different, so that the reverse breakdown voltage of the first sub-cell portion is lower than the reverse breakdown voltage of the second sub-cell portion, which is more conducive to the realization of battery technology.

[0152] Accordingly, in some embodiments, at least one film layer includes at least one functional film layer and at least one other film layer, wherein the film material of one of the functional film layers of the first sub-battery portion is different from the film material of the one of the functional film layers of the second sub-battery portion, and the material of the other film layers of the first sub-battery portion is the same as the thickness of the other film layers of the second sub-battery portion.

[0153] Based on this embodiment, by setting the film material of one of the functional films in the first sub-cell portion and the second sub-cell portion to be different, while setting the film material of the other films in the first sub-cell portion and the second sub-cell portion to be the same, since different film materials typically have different reverse breakdown voltage characteristics, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown voltages. Furthermore, setting the film material of only one functional film layer to be different is also more conducive to process implementation.

[0154] In some embodiments, the functional film layers with different thicknesses or different film materials between the first sub-cell portion and the second sub-cell portion may include a passivation layer and / or a hole transport layer.

[0155] The passivation layer is a film layer that can reduce charge recombination and improve photoelectric conversion efficiency. The hole transport layer is a film layer that can promote the transport of photogenerated holes and block the reverse flow of electrons, which helps to reduce charge recombination and improve the photoelectric conversion efficiency of the battery. Therefore, by setting the passivation layer and / or hole transport layer of the first sub-cell part and the second sub-cell part to different thicknesses or using different film layer materials, the first sub-cell part and the second sub-cell part can have different characteristics in reducing charge recombination and photoelectric conversion efficiency. Based on this, the first sub-cell part and the second sub-cell part can have different reverse breakdown characteristics.

[0156] By using different film materials for the passivation layer and / or hole transport layer of the first sub-cell portion and the second sub-cell portion, different passivation properties and / or hole transport properties can be exhibited. Based on the different passivation properties and / or hole transport properties, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown characteristics, thereby enabling the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0157] In a specific example, as described above, both the first sub-battery portion and the second sub-battery portion include M film layers. The arrangement order and function of the M film layers in the first sub-battery portion and the second sub-battery portion are the same. The difference between the thickness of one functional film layer in the first sub-battery portion and the thickness of the functional film layer in the second sub-battery portion is greater than or equal to a second preset threshold. The thickness of the other film layers in the first sub-battery portion is the same as the thickness of the other film layers in the second sub-battery portion.

[0158] Based on this embodiment, by setting the first sub-cell portion and the second sub-cell portion to have the same number of film layers, the same arrangement order, and the same film layer function, and only the difference in thickness on one of the functional film layers is greater than or equal to a second preset threshold, it is more conducive to process design and implementation.

[0159] In some embodiments, the difference in the number of film layers can also be used to achieve different reverse breakdown voltages between the first sub-cell portion and the second sub-cell portion.

[0160] Accordingly, in some embodiments, the first sub-battery portion includes at least one film layer, the second sub-battery portion includes at least one film layer, and the number of film layers in the second sub-battery portion is greater than the number of film layers in the first sub-battery portion.

[0161] Based on this embodiment, both the first sub-cell portion and the second sub-cell portion may include at least one film layer. The number of film layers in the second sub-cell portion is greater than the number of film layers in the first sub-cell portion. Since different film layers typically require a certain current to be broken down, the second sub-cell portion with more film layers usually has higher reverse breakdown characteristics and is less prone to breakdown than the first sub-cell portion with fewer film layers. This allows the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0162] In some embodiments, the first sub-cell portion includes N film layers, and the second sub-cell portion includes the N film layers and a first passivation layer.

[0163] Where N is a natural number greater than or equal to 1, and the number of N can be set to different values ​​depending on the battery manufacturing process and battery structure design.

[0164] The first sub-cell portion includes N film layers, and the second sub-cell portion includes N film layers and a first passivation layer. This means that, compared with the first sub-cell portion, the second sub-cell portion has the same number and type of N film layers, but also has a first passivation layer. The second sub-cell portion has an additional first passivation layer compared with the first sub-cell portion.

[0165] The functional characteristics of the N film layers in the first sub-cell section and the second sub-cell section can all be different, or there can be two or more film layers with the same functional characteristics, and they are set in different positions in the first sub-cell section or the second sub-cell section.

[0166] Based on this embodiment, since both the first sub-cell portion and the second sub-cell portion have N film layers, the second sub-cell portion further includes a first passivation layer. Since the passivation layer is a film layer that can reduce charge recombination loss, the second sub-cell portion with the added first passivation layer is less likely to be reverse-broken than the first sub-cell portion, regardless of whether the first sub-cell portion includes the second passivation layer. This allows the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0167] The location of the first passivation layer in the second sub-cell section is not limited; some examples are provided below for illustration.

[0168] In some embodiments, taking the N film layers as an example, which at least include a hole transport layer, a photovoltaic layer, an electron transport layer, and an electrode layer arranged sequentially, in some examples the first passivation layer is disposed between the electron transport layer and the electrode layer; in some examples the first passivation layer is disposed between the hole transport layer and the photovoltaic layer; and in some examples the first passivation layer is disposed between both the electron transport layer and the electrode layer and between the hole transport layer and the photovoltaic layer. In this case, the N film layers in the first sub-cell portion and the second sub-cell portion may or may not have a passivation layer, or may have a second passivation layer. For example, the N film layers may or may not include the second passivation layer disposed between the hole transport layer and the photovoltaic layer.

[0169] Based on this embodiment, in the second sub-cell portion of the sub-cell, a first passivation layer can be disposed between the electron transport layer and the electrode layer, thereby passivating the boundary interface between the electron transport layer and the electrode layer. Alternatively, the first passivation layer can be disposed between the hole transport layer and the photovoltaic layer, thereby passivating the boundary interface between the hole transport layer and the photovoltaic layer. Alternatively, a first passivation layer can be disposed between the electron transport layer and the electrode layer, and between the hole transport layer and the photovoltaic layer, respectively, to simultaneously passivate the boundary interfaces between the electron transport layer and the electrode layer, and between the hole transport layer and the photovoltaic layer. Based on this, the second sub-cell portion is less susceptible to reverse breakdown compared to the first sub-cell portion.

[0170] It is understood that among the N film layers of the first sub-cell portion and the second sub-cell portion, there may be no passivation layer (referred to as the second passivation layer in this embodiment) or a passivation layer may be provided, as long as the second sub-cell portion has an additional first passivation layer compared to the first sub-cell portion.

[0171] The location of the second passivation layer is not limited. Taking the N film layers as an example, which at least include a hole transport layer, a photovoltaic layer, an electron transport layer and an electrode layer arranged in sequence, in some examples, the N film layers also include a second passivation layer disposed between the hole transport layer and the photovoltaic layer, and / or a second passivation layer disposed between the electron transport layer and the electrode layer.

[0172] Based on this embodiment, among the N film layers provided in both the first and second sub-cell portions of the sub-cell, a second passivation layer can also be provided between the hole transport layer and the photovoltaic layer, or between the electron transport layer and the electrode layer. Furthermore, a second passivation layer can be provided between the hole transport layer and the photovoltaic layer, and also between the electron transport layer and the electrode layer. Thus, by providing multiple passivation layers, the performance of the cell can be further improved.

[0173] The implementation of the first passivation layer and the second passivation layer is not limited. For example, the first passivation layer and / or the second passivation layer may include a hole blocking layer.

[0174] Combination Figure 2 The example shown illustrates the film structure of the first and second sub-cell portions after the addition of the first passivation layer. Figure 3 As shown.

[0175] based on Figure 3 In the example shown, in the second sub-cell portion of the sub-cell, by disposing a first passivation layer between the electron transport layer and the electrode layer, the boundary interface between the electron transport layer and the electrode layer can be passivated by the first passivation layer, thereby making the second sub-cell portion less susceptible to reverse breakdown compared to the first sub-cell portion.

[0176] In the above embodiments, the types of materials used to implement the first passivation layer and / or the second passivation layer are not limited, and may include, but are not limited to, KI (potassium iodide), KBr (potassium bromide), polycarbazole phosphonic acid, diamine, 1,2-diaminopropane, 1,4-butanediamine, ethylenediamineammonium iodide, etc.

[0177] The location of the first sub-cell within the sub-cell is not limited; it can be located at the edge of the sub-cell, as shown in the top view below. Figure 4 As shown, it can also be placed in the middle of the sub-battery.

[0178] In some embodiments, a plurality of first sub-battery portions 101 may be included, and these plurality of first sub-battery portions 101 are disposed at different positions in the sub-battery 10, and the plurality of sub-battery portions are arranged in parallel, that is, there are a plurality of first sub-battery portions, and each first sub-battery portion is located at a different position in the sub-battery.

[0179] In the case of having multiple first sub-cell portions, the positions of the first sub-cell portions in the sub-cell can be set differently, and can be set uniformly or non-uniformly. In some examples, the multiple first sub-cell portions can be set uniformly in the sub-cell so that the sub-cell can dissipate heat uniformly when the first sub-cell portion of the sub-cell is reversely broken down.

[0180] Based on this embodiment, by setting multiple first sub-battery sections and arranging them in parallel at different locations within the sub-battery sections, the reverse breakdown current can flow through multiple first sub-battery sections, meaning that most of the current can flow through multiple first sub-battery sections, which is more conducive to heat dissipation. On this basis, the heat dissipation performance and safety performance of the thin-film battery device can be improved.

[0181] In some embodiments, the reverse breakdown voltages of each of the first sub-cell portions may be the same or different.

[0182] Based on this embodiment, when multiple first sub-cell portions are provided, the reverse breakdown voltages of the multiple first sub-cell portions can be the same or different, thereby reducing the requirement for consistency of each first sub-cell portion and facilitating the realization of a sub-cell including a first sub-cell portion and a second sub-cell portion.

[0183] In some embodiments, the first sub-cell portion and / or the second sub-cell portion includes a perovskite film layer.

[0184] Based on this embodiment, the first sub-cell portion and / or the second sub-cell portion of the sub-cell include a perovskite film layer, thereby realizing a perovskite cell. Since perovskite photovoltaic cells have extremely high theoretical conversion efficiency, for thin-film battery devices with high conversion efficiency, it is also possible to reduce power loss after some sub-cells are blocked and reverse-broken. It is possible to reduce power loss after being blocked and reverse-broken while maintaining high conversion efficiency.

[0185] The specific value of the first preset threshold is not limited. In some embodiments, the first preset threshold is greater than or equal to 0.5V.

[0186] Experimental simulations revealed that setting the reverse breakdown voltage difference between the first and second sub-cell sections to ≥0.5V significantly improves power loss to a certain extent. Furthermore, by setting the first preset threshold to ≥0.5V, the likelihood of the voltage across the first sub-cell section (with a lower reverse breakdown voltage) slightly increasing due to post-breakdown resistance after breakdown can be reduced, potentially leading to further breakdown of the second sub-cell section with a higher reverse breakdown voltage. Since the reverse breakdown resistance varies for different battery structures, the first preset threshold can be set differently for each structure.

[0187] In some embodiments, the first preset threshold includes 1V.

[0188] Experimental simulations have shown that a reverse breakdown voltage difference of 1V between the first sub-cell and the second sub-cell can significantly improve power loss. Therefore, in some embodiments of this application, the first preset threshold can be set to include 1V so that the first sub-cell and the second sub-cell can have a large difference in reverse breakdown voltage to significantly improve power loss.

[0189] In some embodiments, the difference between the reverse breakdown voltage of the first sub-battery portion and the reverse breakdown voltage of the second sub-battery portion is greater than or equal to the first preset threshold and less than or equal to the third preset threshold.

[0190] Based on this embodiment, by limiting the difference between the reverse breakdown voltage of the first sub-cell portion and the reverse breakdown voltage of the second sub-cell portion to a range between a first preset threshold and a third preset threshold, the difference is neither too small nor too large, so that when the reverse breakdown is blocked, only the first sub-cell portion is broken down, and the second sub-cell portion is not broken down, which is more conducive to the implementation of the process.

[0191] In some embodiments, the ratio of the area of ​​the first sub-battery portion to the area of ​​the sub-battery is greater than a preset ratio.

[0192] When a sub-cell is blocked and the first sub-cell is broken down, most of the current passes through the broken-down area, that is, through the broken-down first sub-cell. If the area of ​​the first sub-cell is too small, it may lead to excessively high energy density. When the energy density is high enough, there may be a possibility of burning out the component.

[0193] The specific value of the preset ratio is not limited. In some embodiments of this application, the preset ratio may include 5%.

[0194] Based on this embodiment, by setting the area of ​​the first sub-battery portion to be larger than the area of ​​the sub-battery by a preset ratio, when the sub-battery is blocked and reversely broken down, most of the current flows through the broken first sub-battery portion, reducing the possibility of the sub-battery burning out due to excessively high energy density caused by the small area of ​​the first sub-battery portion.

[0195] The specific value of the second preset threshold is not limited. In some embodiments, the second preset threshold is greater than or equal to 5 nanometers.

[0196] Experimental simulations revealed that when the thickness difference between the first and second sub-cell portions of the same functional film layer is greater than or equal to 5 nanometers, it is sufficient to create a difference in reverse breakdown voltage between the two sub-cell portions, significantly improving power loss. Furthermore, by ensuring a thickness difference of 5 nanometers between the first and second sub-cell portions, a certain degree of thickness difference is achieved. This satisfies the requirement for easy fabrication while reducing the likelihood that a slight increase in voltage across the first sub-cell portion (with a lower reverse breakdown voltage) due to post-breakdown resistance would further damage the second sub-cell portion (with a higher reverse breakdown voltage). Since the reverse breakdown resistance varies for different battery structures, the second preset threshold can be set differently for each structure.

[0197] In some embodiments, the second preset threshold includes 10 nanometers.

[0198] Experimental simulations revealed that when the thickness difference between the first and second sub-cell portions of the same functional film layer is greater than or equal to 10 nanometers, the first and second sub-cell portions can exhibit a significant difference in reverse breakdown voltage, which can significantly improve power loss. Taking the hole transport layer as an example, when the thickness difference of the hole transport layer between the first and second sub-cell portions reaches 20 nanometers, the reverse breakdown voltage of the first and second sub-cell portions can be greater than 10V. Therefore, in some embodiments of this application, the second preset threshold can be set to include 10 nanometers to enable the first and second sub-cell portions to have a large difference in reverse breakdown voltage, thereby significantly improving power loss.

[0199] Based on the thin-film battery device described in the above embodiments, taking a perovskite battery device as an example, the verification was carried out through equivalent steady-state circuit simulation. The specific verification is as follows.

[0200] First, an equivalent single-diode circuit model of a single perovskite subcell is established. By setting the performance parameters of the diode's forward and reverse characteristics, it is made to almost coincide with the measured data of actual perovskites. The circuit model is as follows: Figure 5 As shown.

[0201] Assuming a perovskite photovoltaic device comprises 150 sub-cells connected in series, its circuit diagram is as follows: Figure 6 As shown.

[0202] In this simulation experiment, multiple sub-cells are connected in series, and each sub-cell consists of two parts connected in parallel: a first sub-cell and a second sub-cell. The electrical schematic diagram is shown below. Figure 7 As shown.

[0203] When one sub-cell is blocked, combined Figure 7 As shown, assuming the reverse breakdown voltage Vbr of the first sub-cell section 101 is 1V and the Vbr of the second sub-cell section 102 is 2V, the voltage between nodes m and n is obtained through simulation (i.e., as shown in the figure). Figure 4 The voltage across battery A shown is 1.1V, slightly higher than the reverse breakdown voltage of 1V for the first sub-cell 101 and lower than the reverse breakdown voltage of 2V for the second sub-cell 102. Since the first sub-cell 101 still has a low resistance after breakdown, the voltage will increase slightly with increasing current. At this point, the first sub-cell 101 is broken down, while the second sub-cell 102 is not. This principle is equivalent to a limiting circuit or a clamping diode. Current flows through both the first sub-cell 101 and the second sub-cell 102. The specific current distribution is related to the ratio of the resistance of the first sub-cell 101 after breakdown to the cutoff resistance of the first sub-cell 102 before breakdown.

[0204] Assuming there are 150 sub-cells, 20 sub-cells experienced breakdown after being blocked. When the blockage is removed, the thin-film battery device resumes normal operation, but the broken-down areas will lose 30% of their voltage (Voc).

[0205] In the simulation, three scenarios were simulated: no low Vbr region in the sub-cell (i.e., no first sub-cell section with a small reverse breakdown voltage, resulting in complete sub-cell breakdown and a 30% Voc loss); a low Vbr region (the area containing the first sub-cell section) comprising 50% (i.e., 50% of the entire sub-cell is broken down, resulting in a 30% Voc loss); and a low Vbr region comprising 5% (i.e., only 5% of the entire sub-cell is broken down, resulting in a 30% Voc loss). The power loss ratio before and after Voc loss was calculated through simulation, and the results are shown in the table below.

[0206]

[0207] As can be seen from Table 1, the smaller the area of ​​the breakdown region, the smaller the impact on the overall system, and the gain is not linear. Compared to a 50% low Vbr area, a 5% low Vbr area reduces power loss by 77.5%, thus the device based on this embodiment can reduce power loss when components are blocked.

[0208] Based on the thin-film battery device described above, some embodiments of this application also provide a method for preparing the thin-film battery device.

[0209] In some embodiments, the method for preparing a thin-film battery device refers to... Figure 8 As shown, it includes the following steps:

[0210] Step S801: Coating the first region portion of the substrate to form the first sub-cell portion of the sub-cell.

[0211] Step S802: Coating the second region portion of the substrate to form the second sub-cell portion of the sub-cell, and making the reverse breakdown voltage of the second sub-cell portion greater than the reverse breakdown voltage of the first sub-cell portion, and the second sub-cell portion is connected in parallel with the first sub-cell portion.

[0212] Step S803: Connect multiple sub-cells in series to form a thin-film battery device.

[0213] Coating is the process of applying a thin layer of coating material, in liquid or powder form, to the surface of objects such as fabrics, paper, metal foil, or plates. Coating is an indispensable step in the production of battery cells and a key process that directly affects various performance characteristics of the battery, including safety, capacity, and lifespan. In the production of battery cells, the coating process is used to coat the positive electrode active material onto the positive electrode current collector, and the negative electrode active material onto the negative electrode current collector. This involves coating a prepared, viscous paste (positive or negative electrode active material) onto a substrate (positive or negative electrode current collector).

[0214] There are no restrictions on the method of forming sub-cells based on the coated substrate, such as slitting, rolling, cutting, assembly, etc., but it is not limited to these methods, as long as sub-cells can be formed based on the coated substrate.

[0215] Based on this embodiment, a first region portion of the substrate and a second region portion of the substrate can be coated to form a first sub-cell portion and a second sub-cell portion, respectively, thereby enabling the formation of a thin-film battery device based on the prepared sub-cells connected in series.

[0216] The first region portion of the substrate and the second region portion of the substrate can be two different substrates, or they can be two different regions on the same substrate. That is, the substrate includes a first region portion (referred to as the first region portion of the substrate in this application embodiment) and a second region portion (referred to as the second region portion of the substrate in this application embodiment), which is more conducive to the realization of the process.

[0217] The method for fabricating a thin-film battery device based on this embodiment involves coating a first region portion of the substrate and a second region portion of the substrate to form a first sub-cell portion and a second sub-cell portion of the sub-cell, respectively. Multiple sub-cells are then connected in series to form the thin-film battery device. Each sub-cell includes a first sub-cell portion and a second sub-cell portion, where the difference in reverse breakdown voltage is greater than or equal to a first preset threshold. The first and second sub-cell portions are connected in parallel to form a limiting structure. In this thin-film battery device, when the reverse voltage across the shielded sub-cell is very high, only the region of the first sub-cell portion with a lower reverse breakdown voltage will be broken down, while the region of the second sub-cell portion with a higher reverse breakdown voltage will not be broken down. This allows the reverse breakdown current to be diverted from the broken first sub-cell portion and the unbroken second sub-cell portion, with the first sub-cell portion becoming the main current path. Therefore, when reverse breakdown would cause destructive damage to the battery assembly, the power loss can be reduced after some sub-cells are shielded and reverse-broken by sacrificing a portion of the sub-cell.

[0218] In some embodiments, the first sub-battery portion includes at least one film layer, and the second sub-battery portion includes at least one film layer;

[0219] The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes:

[0220] The first region portion of the substrate is coated with a first coating amount to form the first sub-cell portion, and the second region portion of the substrate is coated with a second coating amount to form the second sub-cell portion, wherein the second coating amount is greater than the first coating amount.

[0221] The coating amount refers to the mass or quantity of paint applied within a specified area. Therefore, different coating amounts result in different film thicknesses after coating.

[0222] Based on this embodiment, different coating amounts can be used to coat the first region portion of the substrate and the second region portion of the substrate respectively. Due to the different coating amounts, the thickness of the film layer formed on the first region portion of the substrate and the second region portion of the substrate is different, so that the thickness of at least one film layer of the corresponding first sub-cell portion is different from the thickness of at least one film layer of the second sub-cell portion. Since the greater the thickness of the film layer, the lower the possibility of reverse breakdown by current, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown characteristics.

[0223] In some embodiments, the at least one membrane layer includes at least one functional membrane layer and at least one other membrane layer;

[0224] The amount of one functional film layer applied to the first region of the substrate is less than the amount of the second functional film layer applied to the second region of the substrate.

[0225] The amount of other film layers applied to the first region of the substrate is the same as the amount of other film layers applied to the second region of the substrate.

[0226] Based on this embodiment, the coating amount of the first region portion of the substrate differs only when coating one functional film layer, while the coating amount of other film layers is the same. This results in only one functional film layer having a different thickness. Since the greater the film layer thickness, the lower the probability of reverse breakdown by current, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown voltages. Furthermore, by differentiating the coating amount of only one functional film layer, the thickness of the functional film layer in the first sub-cell portion and the second sub-cell portion formed on this basis will be different, which is also more conducive to the realization of the process.

[0227] In some embodiments, the difference between the first coating amount and the second coating amount is greater than a preset coating amount threshold.

[0228] The preset coating amount threshold can be determined based on the requirement of the thickness difference between the first sub-cell portion and the second sub-cell portion formed. Taking the thickness difference between the first sub-cell portion and the second sub-cell portion as an example, the preset coating amount threshold can be determined based on the second preset threshold, the coating area, and the density of the coating material. As long as the thickness difference between the first sub-region portion and the second sub-region portion formed after coating the first sub-region portion substrate and the second sub-region portion substrate based on the difference of the preset coating amount threshold is greater than or equal to the second preset threshold, it is acceptable.

[0229] Based on this embodiment, by limiting the difference between the first coating amount and the second coating amount to be greater than or equal to a preset coating amount threshold, the difference in coating amount will not be too small. In this technology, the difference in thickness will not be too small, so that when the reverse breakdown is blocked, only the first sub-cell part is broken down, and the second sub-cell part is not broken down, which is more conducive to the realization of the process.

[0230] In some embodiments, the first sub-battery portion includes at least one film layer, and the second sub-battery portion includes at least one film layer;

[0231] The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes:

[0232] The substrate in the first region is coated for a first duration to form the first sub-cell portion, and the substrate in the second region is coated for a second duration to form the second sub-cell portion, wherein the second duration is longer than the first duration.

[0233] Generally, the longer the coating time, the greater the coating amount. Therefore, the thickness of the film formed after coating can vary by different coating times. In some optional embodiments, when coating at the same coating speed and coating amount per unit time, the first coating time for the first region of the substrate can be shorter than the second coating time for the second region of the substrate. Thus, the difference in film thickness after coating can be achieved solely by the difference in coating time.

[0234] Based on this embodiment, different coating durations can be applied to the first and second sub-substrates. Due to the different coating durations, the thickness of the film layer formed on the first and second sub-substrates is different, resulting in at least one film layer thickness of the corresponding first sub-cell portion being different from at least one film layer thickness of the second sub-cell portion. Since the greater the film layer thickness, the lower the possibility of reverse breakdown by current, the first and second sub-cell portions can have different reverse breakdown characteristics.

[0235] In some embodiments, the difference between the first duration and the second duration is greater than a preset duration threshold.

[0236] The preset duration threshold can be determined based on the requirement of the thickness difference between the first sub-cell portion and the second sub-cell portion formed. Taking the thickness difference between the first sub-cell portion and the second sub-cell portion as an example, the preset duration threshold can be determined based on the second preset threshold, the coating area, the density of the coating material, and the coating quality per unit time. As long as the thickness difference between the first sub-region portion and the second sub-region portion formed after coating the first sub-region portion substrate and the second sub-region portion substrate based on the difference of the preset duration threshold is greater than or equal to the second preset threshold.

[0237] Based on this embodiment, by limiting the first duration and the second duration to be greater than or equal to a preset duration threshold, the difference in coating amount is not too small. This technology ensures that the difference in thickness is not too small, so that when the reverse breakdown is blocked, only the first sub-cell portion is broken down, and the second sub-cell portion is not broken down. It is also more conducive to the implementation of the process.

[0238] In some embodiments, the at least one membrane layer includes at least one functional membrane layer and at least one other membrane layer; the method further includes:

[0239] The time for coating one of the functional films on the first region of the substrate is less than the time for coating the one of the functional films on the second region of the substrate.

[0240] The time taken to coat other film layers on the first region of the substrate is the same as the time taken to coat other film layers on the second region of the substrate.

[0241] Based on this embodiment, the coating time for the first region portion of the substrate and the first region portion of the substrate differs only when coating one of the functional film layers, while the coating time for other film layers is the same. This results in only one functional film layer having a different thickness. Since the greater the film layer thickness, the lower the possibility of reverse breakdown by current, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown voltages. Furthermore, by differentiating the coating time for only one functional film layer, the thickness of the functional film layer in the first sub-cell portion and the second sub-cell portion formed on this basis will be different, which is also more conducive to the realization of the process.

[0242] In some embodiments, the first sub-battery portion includes at least one film layer, and the second sub-battery portion includes at least one film layer;

[0243] The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes:

[0244] A first film material is coated onto a portion of the substrate in the first region to form the first sub-cell portion, and a second film material is coated onto a portion of the substrate in the second region to form the second sub-cell portion. The first film material and the second film material are different.

[0245] Based on this embodiment, different film materials are used when coating the first region portion of the substrate and the second region portion of the substrate. Since different film materials usually have different reverse breakdown voltage characteristics, the first sub-cell portion and the second sub-cell portion formed on this basis can have different reverse breakdown characteristics by selecting the film material.

[0246] In some embodiments, the at least one membrane layer includes at least one functional membrane layer and at least one other membrane layer, and the method further includes:

[0247] A first functional film material is coated onto a portion of the substrate in the first region to form one of the functional film layers of the first sub-battery portion; and a second functional film material is coated onto a portion of the substrate in the second region to form one of the functional film layers of the second sub-battery portion, wherein the first functional film material and the second film material have different functions.

[0248] A third film material is applied to a portion of the substrate in the first region to form other film layers for the first sub-cell portion, and the third film material is applied to a portion of the substrate in the second region to form other film layers for the second sub-cell portion.

[0249] Based on this embodiment, when coating the first and second regional substrates, a different functional film material is used only for coating one of the functional film layers, while the other film layers use the same film material. Since different film materials typically have different reverse breakdown voltage characteristics, the first and second sub-cell portions formed on this basis can have different reverse breakdown voltages. Furthermore, using a different functional film material for only one functional film layer is more conducive to process implementation.

[0250] In some embodiments, one of the functional membrane layers includes a passivation layer and / or a hole transport layer.

[0251] Based on this embodiment, when using the first region portion of the substrate and the second region portion of the substrate, by setting different coating amounts and coating durations for the passivation layer and / or hole transport layer, or by using different functional film layer materials, different passivation properties and / or hole transport properties can be exhibited. Based on the different passivation properties and / or hole transport properties, the first sub-cell portion and the second sub-cell portion formed on this basis can have different reverse breakdown characteristics, thereby enabling the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0252] In some embodiments, the first sub-battery portion includes at least one film layer, and the second sub-battery portion includes at least one film layer;

[0253] The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the first sub-cell portion, includes:

[0254] A first number of film layers are coated on a portion of the substrate in the first region to form the first sub-cell portion, and a second number of film layers are coated on a portion of the substrate in the second region to form the second sub-cell portion, wherein the second number is greater than the first number.

[0255] Based on this embodiment, when coating the first region portion of the substrate and the second region portion of the substrate, more film layers are coated on the second region portion of the substrate. On this basis, a first sub-cell portion and a second sub-cell portion with different film layer numbers can be formed. Since different film layers usually require a certain current to be broken down, the second sub-cell portion with more film layer numbers usually has higher reverse breakdown characteristics and is less likely to be broken down than the first sub-cell portion with fewer film layer numbers. Thus, the first sub-cell portion and the second sub-cell portion can have different reverse breakdown voltages.

[0256] In some embodiments, the second plurality of film layers includes the first plurality of film layers and the first passivation layer.

[0257] Based on this embodiment, in addition to having a first number of film layers, the first sub-cell portion and the second sub-cell portion formed by coating the first region portion substrate and the second region portion substrate further include a first passivation layer. Since the passivation layer is a film layer that can reduce charge recombination loss, the second sub-cell portion with the added first passivation layer is less likely to be reverse broken down compared to the first sub-cell portion, thereby enabling the first sub-cell portion and the second sub-cell portion to have different reverse breakdown voltages.

[0258] In some embodiments, the ratio of the area of ​​the first region portion of the substrate to the area of ​​the substrate including the first region portion of the substrate and the second region portion of the substrate is greater than a preset ratio.

[0259] Based on this embodiment, by setting the area of ​​the first region portion of the substrate to be larger than the area of ​​the substrate including the first region portion of the substrate and the second region portion of the substrate by a preset ratio, and then forming the sub-cell on this basis, the area of ​​the first sub-cell portion is set to be larger than the area of ​​the sub-cell by a preset ratio. This allows most of the current to flow through the first sub-cell portion that is broken down when the sub-cell is blocked, thus reducing the possibility of the sub-cell burning out due to excessively high energy density caused by the small area of ​​the first sub-cell portion.

[0260] In some embodiments, the preset ratio includes 5%.

[0261] Based on the fabrication method of the thin-film battery device described above, in a specific example, a thin-film battery device is formed by partially coating two regions of a substrate with only different coating amounts or coating times, and then forming sub-cells and sub-cells connected in series. (Refer to...) Figure 9 As shown, the fabrication method of the thin-film battery device in this example includes:

[0262] Step S901: Apply a first number of functional film layers to the first region portion of the substrate and the second region portion of the substrate, respectively, wherein the arrangement order, film layer function, film layer material and film layer thickness of the first number of functional film layers of the first region portion of the substrate and the second region portion of the substrate are the same.

[0263] Step S902: Using a first functional film layer material, a first coating amount or a first duration is applied to the first region portion of the substrate to form a first functional film layer, and using the first functional film layer material, a second coating amount or a second duration is applied to the second region portion of the substrate to form a first functional film layer.

[0264] Step S903: Form sub-cells based on the coated substrate, and connect multiple sub-cells in series to form a thin-film battery device, wherein the reverse breakdown voltage of the first sub-cell portion corresponding to the first region portion of the substrate is less than the reverse breakdown voltage of the second sub-cell portion corresponding to the second region portion of the substrate and connected in parallel with the first sub-cell portion.

[0265] There are no restrictions on the method of forming batteries based on the coated substrate, such as slitting, rolling, cutting, assembly, etc., but it is not limited to these, as long as batteries can be produced based on the coated substrate.

[0266] Based on this embodiment, during the fabrication of the thin-film battery device, when coating the substrate used to form the battery, there is a difference in the coating of the first region portion of the substrate and the second region portion of the substrate. Specifically, for the first region portion of the substrate and the second region portion of the substrate, a first number of functional film layers with the same arrangement order, film layer function, film layer material, and film layer thickness are coated, and the same first functional film layer material is used. A first preset thickness is applied to the first region portion of the substrate, and a second preset thickness is applied to the second region portion of the substrate, so that the film layer thicknesses of the first region portion of the substrate and the second region portion of the substrate are different after coating. Since the film layer thickness is larger, the possibility of reverse breakdown by current after the battery is fabricated is lower. Therefore, after the battery is fabricated based on the coated substrate, the battery includes a first sub-cell portion corresponding to the first region portion of the substrate and a second sub-cell portion corresponding to the second region portion of the substrate connected in parallel with the first sub-cell portion, and the first sub-cell portion and the second sub-cell portion have different reverse breakdown voltages. This allows the sub-cells obtained from this design to be used in such a way that when the reverse voltage across the shielded sub-cell is very high, only the area of ​​the first sub-cell with a lower reverse breakdown voltage will be broken down, while the area of ​​the second sub-cell with a higher reverse breakdown voltage will not be broken down. This allows the reverse breakdown current to be diverted from the broken first sub-cell and the unbroken second sub-cell, with the first sub-cell becoming the main path for the current. Thus, when reverse breakdown would cause destructive damage to the battery assembly, the power loss can be reduced by sacrificing a portion of the sub-cell to protect the other parts of the sub-cell, even after some sub-cells are shielded and reverse-broken.

[0267] Based on the fabrication method of the thin-film battery device described above, in a specific example, two regions of a substrate are partially coated with only different coating materials, and a sub-cell and a thin-film battery device consisting of sub-cells connected in series are formed on this basis. (Refer to...) Figure 10 As shown, the fabrication method of the thin-film battery device in this example includes:

[0268] Step S1001: Apply a first number of functional film layers to the first region portion of the substrate and the second region portion of the substrate, respectively, wherein the arrangement order, film layer function, film layer material and film layer thickness of the first number of functional film layers of the first region portion of the substrate and the second region portion of the substrate are the same.

[0269] Step S1002: Using a first functional film layer material, a first functional film layer of a first preset thickness is applied to the first region portion of the substrate, and using a second functional film layer material, a first functional film layer of a second preset thickness is applied to the second region portion of the substrate, wherein the first functional film layer material and the second functional film layer material are different, and the first preset thickness and the second preset thickness are the same or different.

[0270] The first functional film layer material is one type of coating material used to achieve the function of the first functional film layer after coating. The second functional film layer material is another type of coating material used to achieve the function of the first functional film layer after coating. That is, the first functional film layer can be achieved by coating the first functional film layer material or by coating the second functional film layer material.

[0271] Step S1003: Form sub-cells based on the coated substrate, and connect multiple sub-cells in series to form a thin-film battery device, wherein the reverse breakdown voltage of the first sub-cell portion corresponding to the first region portion of the substrate is less than the reverse breakdown voltage of the second sub-cell portion corresponding to the second region portion of the substrate and connected in parallel with the first sub-cell portion.

[0272] Based on this embodiment, during the fabrication of the thin-film battery device, when coating the substrate used to form the battery, there is a difference in the coating of the first region portion of the substrate and the second region portion of the substrate. Specifically, for the first region portion of the substrate and the second region portion of the substrate, a first number of functional film layers with the same arrangement order, film layer function, film layer material, and film layer thickness are coated. For the first functional film layer, the first functional film layer material is coated with a first preset thickness in the first region portion of the substrate, and the second functional film layer material is coated with a second thickness in the second region portion of the substrate. Since different film layer materials usually have different reverse breakdown voltage characteristics, after the battery is fabricated based on the coated substrate, the battery includes a first sub-cell portion corresponding to the first region portion of the substrate and a second sub-cell portion corresponding to the second region portion of the substrate connected in parallel with the first sub-cell portion. The first sub-cell portion and the second sub-cell portion have different reverse breakdown voltages. This allows the sub-cells obtained from this design to be used in such a way that when the reverse voltage across the shielded sub-cell is very high, only the area of ​​the first sub-cell with a lower reverse breakdown voltage will be broken down, while the area of ​​the second sub-cell with a higher reverse breakdown voltage will not be broken down. This allows the reverse breakdown current to be diverted from the broken first sub-cell and the unbroken second sub-cell, with the first sub-cell becoming the main path for the current. Thus, when reverse breakdown would cause destructive damage to the battery assembly, the power loss can be reduced by sacrificing a portion of the sub-cell to protect the other parts of the sub-cell, even after some sub-cells are shielded and reverse-broken.

[0273] Based on the fabrication method of the thin-film battery device described above, in a specific example, taking the coating of different numbers of film layers on two regions of a substrate, and the formation of sub-cells and thin-film battery devices connected in series on this basis as an example, refer to... Figure 11 As shown, the fabrication method of the thin-film battery device in this example includes:

[0274] Step S1101: Apply a first number of functional film layers to the first region portion of the substrate and the second region portion of the substrate, respectively, wherein the arrangement order, film layer function, film layer material and film layer thickness of the first number of functional film layers of the first region portion of the substrate and the second region portion of the substrate are the same.

[0275] Step S1102: On the second region portion of the substrate, after the first number of functional film layers are coated, a second functional film layer is coated.

[0276] The first number of functional film layers applied may include a second functional film layer or may not include a second functional film layer.

[0277] The specific type of the second functional film layer is not limited, and in some embodiments it may include a passivation layer. In this case, the first number of applied functional films may or may not include a passivation layer. The specific arrangement of the films can be the same as described above for the thin-film battery device, and will not be repeated here.

[0278] Step S1103: Form sub-cells based on the coated substrate, and connect multiple sub-cells in series to form a thin-film battery device, wherein the reverse breakdown voltage of the first sub-cell portion corresponding to the first region portion of the substrate is less than the reverse breakdown voltage of the second sub-cell portion corresponding to the second region portion of the substrate and connected in parallel with the first sub-cell portion.

[0279] Based on this embodiment, in the fabrication of a thin-film battery device, when coating the substrate used to form the battery, there is a difference in the coating of the first region portion of the substrate and the second region portion of the substrate. Specifically, a first number of functional film layers with the same arrangement order, film layer function, film layer material, and film layer thickness are coated on the first region portion of the substrate and the second region portion of the substrate, respectively. Furthermore, a second functional film layer is coated on the second region portion of the substrate. Since different film layers usually require a certain current to be broken down, the portion with more film layers usually has higher reverse breakdown characteristics than the portion with fewer film layers. This allows the battery to be fabricated based on the coated substrate, such that the battery includes a first sub-cell portion corresponding to the first region portion of the substrate and a second sub-cell portion corresponding to the second region portion of the substrate connected in parallel with the first sub-cell portion, and the first sub-cell portion and the second sub-cell portion have different reverse breakdown voltages. This allows the sub-cells obtained from this design to be used in such a way that when the reverse voltage across the shielded sub-cell is very high, only the area of ​​the first sub-cell with a lower reverse breakdown voltage will be broken down, while the area of ​​the second sub-cell with a higher reverse breakdown voltage will not be broken down. This allows the reverse breakdown current to be diverted from the broken first sub-cell and the unbroken second sub-cell, with the first sub-cell becoming the main path for the current. Thus, when reverse breakdown would cause destructive damage to the battery assembly, the power loss can be reduced by sacrificing a portion of the sub-cell to protect the other parts of the sub-cell, even after some sub-cells are shielded and reverse-broken.

[0280] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0281] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above 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.

[0282] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A thin film battery device, characterized by, The thin-film battery device includes: a plurality of sub-cells connected in series, each sub-cell comprising: First sub-battery section; A second sub-cell section connected in parallel with the first sub-cell section, wherein the second sub-cell section is configured to have a reverse breakdown voltage greater than that of the first sub-cell section.

2. The thin-film battery device according to claim 1, characterized in that, The difference between the reverse breakdown voltage of the first sub-cell portion and the reverse breakdown voltage of the second sub-cell portion is greater than or equal to a first preset threshold.

3. The thin-film battery device according to claim 1 or 2, characterized in that, The first sub-cell portion includes at least one film layer, the second sub-cell portion includes at least one film layer, and the thickness of the at least one film layer of the first sub-cell portion is less than the thickness of the at least one film layer of the second sub-cell portion.

4. The thin-film battery device according to claim 3, characterized in that, The at least one film layer includes at least one functional film layer, the thickness of one of the functional film layers in the first sub-battery portion is less than the thickness of the one of the functional film layers in the second sub-battery portion, and the thickness of the other film layers in the first sub-battery portion is the same as the thickness of the other film layers in the second sub-battery portion.

5. The thin-film battery device according to claim 4, characterized in that, The film material of at least one film layer of the first sub-battery portion is the same as the film material of at least one film layer of the second sub-battery portion.

6. The thin-film battery device according to any one of claims 3 to 5, characterized in that, The difference between the thickness of at least one film layer of the first sub-battery portion and the thickness of at least one film layer of the second sub-battery portion is greater than or equal to a second preset threshold.

7. The thin-film battery device according to any one of claims 1 to 5, characterized in that, The first sub-cell portion includes at least one film layer, the second sub-cell portion includes at least one film layer, and the film layer material of the at least one film layer of the first sub-cell portion is different from the film layer material of the at least one film layer of the second sub-cell portion.

8. The thin-film battery device according to claim 6, characterized in that, The at least one film layer includes at least one functional film layer, wherein the film layer material of one of the functional film layers of the first sub-battery portion is the same as the film layer material of one of the functional film layers of the second sub-battery portion, and the materials of the other film layers of the first sub-battery portion are the same as the materials of the other film layers of the second sub-battery portion.

9. The thin-film battery device according to claim 4, 5, or 8, characterized in that, One of the functional membrane layers includes a passivation layer and / or a hole transport layer.

10. The thin-film battery device according to any one of claims 1 to 9, characterized in that, The first sub-battery portion includes at least one film layer, the second sub-battery portion includes at least one film layer, and the number of film layers in the second sub-battery portion is greater than the number of film layers in the first sub-battery portion.

11. The thin-film battery device according to claim 10, characterized in that, The first sub-cell portion includes N film layers, and the second sub-cell portion includes the N film layers and a first passivation layer.

12. The thin-film battery device according to claim 11, characterized in that, The N film layers include at least a hole transport layer, a photovoltaic layer, an electron transport layer, and an electrode layer arranged sequentially, wherein; The first passivation layer is disposed between the electron transport layer and the electrode layer; and / or The first passivation layer is disposed between the hole transport layer and the photovoltaic layer.

13. The thin-film battery device according to claim 12, characterized in that, The N film layers further include a second passivation layer disposed between the hole transport layer and the photovoltaic layer, and / or a second passivation layer disposed between the electron transport layer and the electrode layer.

14. The thin-film battery device according to any one of claims 11 to 13, characterized in that, The first passivation layer and / or the second passivation layer include a hole blocking layer.

15. The thin-film battery device according to any one of claims 1 to 14, characterized in that, The first sub-battery section includes multiple sub-battery sections, and each first sub-battery section is arranged in parallel.

16. The thin-film battery device according to any one of claims 2 to 15, characterized in that, The first preset threshold is greater than or equal to 0.5V.

17. The thin-film battery device according to claim 16, characterized in that, The first preset threshold includes 1V.

18. The thin-film battery device according to claim 1 or 2, characterized in that, Both the first sub-battery section and the second sub-battery section include M film layers. The arrangement order and function of the M film layers in the first sub-battery section and the second sub-battery section are the same. The difference between the thickness of one film layer in the first sub-battery section and the thickness of one film layer in the second sub-battery section is greater than or equal to a second preset threshold. The thickness of the other film layers in the first sub-battery section is the same as the thickness of the other film layers in the second sub-battery section.

19. The thin-film battery device according to any one of claims 1 to 18, characterized in that, The difference between the reverse breakdown voltage of the first sub-cell portion and the reverse breakdown voltage of the second sub-cell portion is greater than or equal to a first preset threshold and less than or equal to a third preset threshold.

20. The thin-film battery device according to any one of claims 1 to 19, characterized in that, The ratio of the area of ​​the first sub-battery portion to the area of ​​the sub-battery is greater than a preset ratio.

21. The thin-film battery device according to claim 20, characterized in that, The preset ratio includes 5%.

22. The thin-film battery device according to claim 6, characterized in that, The second preset threshold is greater than or equal to 5 nanometers.

23. The thin-film battery device according to claim 22, characterized in that, The second preset threshold includes 10 nanometers.

24. A method for preparing a thin-film battery device, characterized in that, Includes the following steps: The substrate in the first region is coated to form the first sub-cell portion of the sub-cell; The substrate in the second region is coated to form the second sub-cell portion of the sub-cell, and the reverse breakdown voltage of the second sub-cell portion is greater than the reverse breakdown voltage of the first sub-cell portion, and the second sub-cell portion is connected in parallel with the first sub-cell portion. Multiple sub-cells are connected in series to form a thin-film battery device.

25. The method according to claim 24, characterized in that, The first sub-cell portion includes at least one film layer, and the second sub-cell portion includes at least one film layer; The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes: The first region portion of the substrate is coated with a first coating amount to form the first sub-cell portion, and the second region portion of the substrate is coated with a second coating amount to form the first sub-cell portion, wherein the second coating amount is greater than the first coating amount.

26. The method according to claim 25, characterized in that, The at least one membrane layer includes at least one functional membrane layer; The amount of one functional film layer applied to the first region of the substrate is less than the amount of the second functional film layer applied to the second region of the substrate. The amount of other film layers applied to the first region of the substrate is the same as the amount of other film layers applied to the second region of the substrate.

27. The method according to claim 25 or 26, characterized in that, The difference between the first coating amount and the second coating amount is greater than the preset coating amount threshold.

28. The method according to any one of claims 24 to 27, characterized in that, The first sub-cell portion includes at least one film layer, and the second sub-cell portion includes at least one film layer; The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes: The substrate in the first region is coated for a first duration to form the first sub-cell portion, and the substrate in the second region is coated for a second duration to form the second sub-cell portion, wherein the second duration is longer than the first duration.

29. The method according to claim 28, characterized in that, The at least one membrane layer includes at least one functional membrane layer; the method further includes: The time for coating one of the functional films on the first region of the substrate is less than the time for coating the one of the functional films on the second region of the substrate. The time taken to coat other film layers on the first region of the substrate is the same as the time taken to coat other film layers on the second region of the substrate.

30. The method according to any one of claims 24 to 29, characterized in that, The first sub-cell portion includes at least one film layer, and the second sub-cell portion includes at least one film layer; The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes: A first film material is coated onto a portion of the substrate in the first region to form the first sub-cell portion, and a second film material is coated onto a portion of the substrate in the second region to form the second sub-cell portion. The first film material and the second film material are different.

31. The method according to claim 30, characterized in that, The at least one membrane layer includes at least one functional membrane layer, and the method further includes: A first functional film material is coated onto a portion of the substrate in the first region to form one of the functional film layers of the first sub-battery portion; and a second functional film material is coated onto a portion of the substrate in the second region to form one of the functional film layers of the second sub-battery portion, wherein the first functional film material and the second film material have different functions. A third film material is applied to a portion of the substrate in the first region to form other film layers for the first sub-cell portion, and the third film material is applied to a portion of the substrate in the second region to form other film layers for the second sub-cell portion.

32. The method according to any one of claims 26, 27, 29, and 31, characterized in that, One of the functional membrane layers includes a passivation layer and / or a hole transport layer.

33. The method according to any one of claims 24 to 32, characterized in that, The first sub-cell portion includes at least one film layer, and the second sub-cell portion includes at least one film layer; The process of coating a portion of the substrate in a first region to form the first sub-cell portion, and coating a portion of the substrate in a second region to form the second sub-cell portion, includes: A first number of film layers are coated on a portion of the substrate in the first region to form the first sub-cell portion, and a second number of film layers are coated on a portion of the substrate in the second region to form the second sub-cell portion, wherein the second number is greater than the first number.

34. The method according to claim 33, characterized in that, The second number of film layers includes the first number of film layers and the first passivation layer.

35. The method according to any one of claims 24 to 34, characterized in that, The ratio of the area of ​​the first region portion of the substrate to the area of ​​the substrate including the first region portion of the substrate and the second region portion of the substrate is greater than a preset ratio.

36. The method according to claim 35, characterized in that, The preset ratio includes 5%.

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