Titanium niobate battery, preparation method thereof and power system device

Abstract

The invention discloses a titanium niobate battery, a preparation method thereof and a power system device, the titanium niobate battery comprises a titanium niobate negative pole piece, a lithium nickel manganese oxide positive pole piece and an electrolyte arranged between the titanium niobate negative pole piece and the lithium nickel manganese oxide positive pole piece, the lithium nickel manganese oxide positive pole piece comprises at least two of an organic solvent gelatinized organic polymer material, a novel lithium salt and solid electrolyte particles, and a lithium nickel manganese oxide positive pole material; the titanium niobate negative electrode plate comprises at least two of an organic solvent gelatinized organic polymer material, a novel lithium salt and solid electrolyte particles, and a titanium niobate negative electrode material. According to the invention, the shuttle effect of negative electrode damage caused by side reaction products of lithium nickel manganese oxide under high voltage is solved, the titanium niobate negative electrode is protected by the conductive ion layer on the surface of the negative electrode material, the titanium niobate negative electrode is protected from being attacked by positive electrode oxidation products, the stability of the surface of the negative electrode is improved, and the problem of industrialization of the nickel manganese titanium niobate battery is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and in particular relates to a titanium niobate battery and a preparation method thereof, and a power system device. Background Art

[0002] At present, fuel cell vehicles have become the development direction of new energy vehicles in the future. However, the power of fuel cell vehicles is limited by the fuel cell. The cost of high-power fuel cells is very high. If fuel cell vehicles are equipped with high-rate lithium batteries, the cost of fuel cell vehicles can be greatly reduced. However, the safety and rate performance of lithium batteries need to be improved.

[0003] If existing batteries such as lithium iron phosphate or ternary batteries are used as auxiliary batteries for fuel cell vehicles, the graphite negative electrode is prone to lithium deposition at high rates, causing safety problems. At the same time, the cycle life of the battery will also be greatly reduced at high rates. Summary of the invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a titanium niobate battery and a preparation method thereof, and a power system device. The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0005] One aspect of the present invention provides a titanium niobate battery, comprising a titanium niobate negative electrode sheet, a lithium nickel manganese oxide positive electrode sheet, and an electrolyte disposed between the titanium niobate negative electrode sheet and the lithium nickel manganese oxide positive electrode sheet, wherein:

[0006] The lithium nickel manganese oxide positive electrode plate comprises at least two of an organic polymer material, a novel lithium salt and solid electrolyte particles and a lithium nickel manganese oxide positive electrode material, wherein the lithium nickel manganese oxide positive electrode material accounts for 70-98% by weight;

[0007] The titanium niobate negative electrode plate comprises an organic polymer material, at least two of a novel lithium salt and solid electrolyte particles and a titanium niobate negative electrode material, wherein the mass ratio of the titanium niobate negative electrode material is 70-98%.

[0008] In one embodiment of the present invention, the titanium niobate negative electrode material includes a crystal form of TiNb 2 O 7 、Ti 2 Nb 10 O 29 or Ti 2 Nb 24 O 62 Any material containing niobium, titanium and oxygen; the lithium nickel manganese oxide positive electrode material includes any material containing manganese and nickel in the form of spinel lithium nickel manganese oxide.

[0009] In one embodiment of the present invention, the organic polymer material includes any one of polyacrylonitrile, polyethylene oxide, polyvinylidene fluoride and polymethyl methacrylate.

[0010] In one embodiment of the present invention, the novel lithium salt includes any one of LFSI or LTFSI.

[0011] In one embodiment of the present invention, the solid electrolyte particles include an inorganic compound having a perovskite structure, an inorganic compound having a LISICON structure, a Li 1+x Al x Ti 2-x (PO 4 ) 3 , Li 3.6 Si 0.6 PO 4 , amorphous Li 2.9 PO 3.3 N 0.46 , lithium calcium zirconium oxide, lithium lanthanum zirconium oxide with garnet structure Li 7 La 3 Zr 2 O 12 and at least one of its coated and doped derivatives, wherein 0.1≤x≤0.4.

[0012] In one embodiment of the present invention, the charging cut-off voltage range of the titanium niobate battery is 3.3-3.9V, the discharging cut-off voltage range is 1-2.5V, and the rated voltage is 2.6-3.3V.

[0013] Another aspect of the present invention provides a method for preparing a titanium niobate battery, the method comprising:

[0014] S1: adding a preset ratio of lithium nickel manganese oxide positive electrode material, conductive carbon black, solid electrolyte particles and organic polymer material into an N-methylpyrrolidone solvent and mixing to obtain a first slurry, coating the first slurry on both sides of a collector formed of an aluminum foil, and then drying and rolling to obtain a lithium nickel manganese oxide positive electrode sheet;

[0015] S2: adding a preset ratio of titanium niobate powder, an organic polymer material, solid electrolyte particles, and conductive carbon black into an N-methylpyrrolidone solvent and mixing them to obtain a second slurry, coating the second slurry on both sides of a collector formed of a copper foil, and then drying and rolling to obtain a titanium niobate negative electrode sheet;

[0016] S3: using a double-layer polyethylene material coated with aluminum oxide of appropriate thickness as the diaphragm;

[0017] S4: The lithium nickel manganese oxide positive electrode sheet, the titanium niobate negative electrode sheet, the separator and the electrolyte are used to make a titanium niobate battery.

[0018] In one embodiment of the present invention, the electrolyte contains 1 mol / L LiPF 6 The solvents propylene carbonate, ethyl methyl carbonate and diethyl carbonate are mixed in a volume ratio of 1:1:1.

[0019] Another aspect of the present invention provides a power system device for a fuel cell vehicle, comprising a fuel cell, a motor and a titanium niobate battery, wherein:

[0020] The fuel cell and the titanium niobate battery can supply power to the motor, and the fuel cell can supply power to the titanium niobate battery.

[0021] In one embodiment of the present invention, the calling method of the power system device includes:

[0022] Starting the fuel cell vehicle, obtaining the current power of the titanium niobate battery, when the power of the titanium niobate battery is greater than a preset first power, prohibiting the starting of the fuel cell, and starting the titanium niobate battery at the same time; when the power of the titanium niobate battery is less than a preset second power, starting the fuel cell, and charging the titanium niobate battery by the fuel cell; when the power of the titanium niobate battery is at a preset third power, prohibiting the fuel cell from charging the titanium niobate battery;

[0023] When the output power of the fuel cell is less than the requested power of the vehicle, the titanium niobate battery is started.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] 1. The present invention provides a titanium niobate battery and a preparation method thereof, applies the titanium niobate battery to hydrogen fuel vehicles and discloses a method for using the titanium niobate battery in hydrogen fuel vehicles, that is, a power system device including a titanium niobate battery is used, which is different from the existing device, wherein a new type of titanium niobate battery module is used, and the shuttle effect of the side reaction products of nickel manganese oxide under high voltage on the negative electrode is solved through the innovative design of the negative electrode plate, and the titanium niobate negative electrode is protected by the ion-conducting layer on the surface of the negative electrode material, on the one hand, it is protected from the attack of the positive electrode oxidation products, and on the other hand, the surface stability of the negative electrode itself is increased, solving the key problem of the industrialization of nickel manganese titanium niobate battery. By introducing the titanium niobate battery into the vehicle, the control system and hardware system of the vehicle can be greatly simplified, especially in the past, hydrogen fuel vehicles need to carry out redundant control system design and hardware design for safety needs, and introducing the titanium niobate battery into the vehicle will increase the power performance of the vehicle and reduce the cost of the vehicle. This is all due to the high safety, long life and high rate of titanium niobate batteries. The present invention also provides a method for calling the titanium niobate battery in a fuel vehicle, which can ensure better performance of the vehicle and greatly save the power consumption of hydrogen fuel vehicles.

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a flow chart of a method for preparing a titanium niobate battery provided by an embodiment of the present invention;

[0028] Figure 2 It is a structural schematic diagram of a power system device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0029] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, a titanium niobate battery and its preparation method and a power system device proposed in accordance with the present invention are described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0030] The above and other technical contents, features and effects of the present invention are clearly presented in the following detailed description of the specific implementation modes in conjunction with the accompanying drawings. Through the description of the specific implementation modes, the technical means and effects adopted by the present invention to achieve the predetermined purpose can be more deeply and specifically understood. However, the attached drawings are only for reference and explanation purposes and are not used to limit the technical solutions of the present invention.

[0031] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants are intended to cover non-exclusive inclusion, so that an article or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed. In the absence of more restrictions, the elements defined by the statement "including one..." do not exclude the existence of other identical elements in the article or device including the elements.

[0032] Embodiment 1

[0033] The present embodiment provides a titanium niobate battery, comprising a titanium niobate negative electrode plate, a lithium nickel manganese oxide positive electrode plate, and an electrolyte arranged between the titanium niobate negative electrode plate and the lithium nickel manganese oxide positive electrode plate, wherein the lithium nickel manganese oxide positive electrode plate comprises an organic polymer material gelled by an organic solvent, at least two of a novel lithium salt and solid electrolyte particles, and a lithium nickel manganese oxide positive electrode material, wherein the mass ratio of the lithium nickel manganese oxide positive electrode material is 70-98%, and the mass ratio of the remaining raw materials is 0-5%; the titanium niobate negative electrode plate comprises an organic polymer material gelled by an organic solvent, at least two of a novel lithium salt and solid electrolyte particles, and a titanium niobate negative electrode material, wherein the mass ratio of the titanium niobate negative electrode material is 70-98%, and the mass ratio of the remaining raw materials is 0-5%.

[0034] The titanium niobate negative electrode material of this embodiment includes a crystal form of TiNb 2 O 7 、Ti 2 Nb 10 O 29 or Ti 2 Nb 24 O 62 Any one of the negative electrode materials containing niobium, titanium and oxygen elements. Further, the titanium niobate negative electrode material also includes any coating and doping combination of the above three crystal materials, and the doped or coated material still contains the crystal forms of the above three titanium niobate negative electrode materials.

[0035] The lithium nickel manganese oxide positive electrode material of this embodiment includes any material containing manganese and nickel elements in the form of spinel high-voltage lithium nickel manganese oxide. The above spinel high-voltage lithium nickel manganese oxide material includes any coating and doping combination of the above lithium nickel manganese oxide material, and the doped or coated material still includes the crystal form of the spinel lithium nickel manganese oxide material.

[0036] Further, the organic polymer material includes any one of polyacrylonitrile (PAN), polyethylene oxide (PEO), polyvinylidene fluoride (PVdF, HPF-PVDF) and polymethyl methacrylate. The novel lithium salt of this embodiment includes any one of LFSI and LTFSI.

[0037] The solid electrolyte particles of this embodiment include an inorganic compound with a perovskite structure, namely, a lithium lanthanum titanium composite oxide, an inorganic compound with a LISICON structure, and LATP (Li 1+x Al x Ti 2-x (PO 4 ) 3 , where 0.1≤x≤0.4, Li 3.6 Si 0.6 PO 4 , amorphous LIPON (Li 2.9 PO 3.3 N 0.46 ), lithium calcium zirconium oxide, lithium lanthanum zirconium oxide LLZO (Li 7 La 3 Zr 2 O 12 ) and at least one of the coated doped derivatives of the above substances, such as LLZTO (Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 ).

[0038] In addition, the lithium nickel manganese oxide positive electrode plate and the titanium niobate negative electrode plate of this embodiment also include conductive carbon black and a binder in appropriate proportions, wherein the conductive carbon black can be a conductive substance such as Super P, acetylene black, Ketjen black, carbon nanotubes, etc., and the binder can be PVDF (polyvinylidene fluoride), PTFE (polytetrafluoroethylene), CMC (carboxymethyl cellulose), SBR (styrene butadiene rubber), polyimide, polyacrylic acid or lithium polyacrylate and the like.

[0039] The titanium niobate battery also includes a diaphragm of double-layer aluminum oxide-coated PE with an appropriate thickness. Preferably, the thickness of the diaphragm is 16 μm. The electrolyte contains 1 mol / L concentration of LiPF 6 The (lithium hexafluorophosphate) solvent propylene carbonate (PC), ethyl methyl carbonate and diethyl carbonate (DEC) are mixed in a volume ratio of 1:1:1.

[0040] The charging cut-off voltage range of the titanium niobate battery is 3.3-3.9V, the discharging cut-off voltage range is 1-2.5V, and the rated voltage is 2.6-3.3V.

[0041] Embodiment 2

[0042] Based on the examples, this example provides a method for preparing a titanium niobate battery, such as Figure 1 As shown, the preparation method comprises:

[0043] S1: Add a preset proportion of lithium nickel manganese oxide positive electrode material, organic polymer material, solid electrolyte particles and conductive carbon black into N-methylpyrrolidone solvent and mix to obtain a first slurry, apply the first slurry on both sides of a collector formed by aluminum foil, and then dry and roll-press to obtain a lithium nickel manganese oxide positive electrode sheet.

[0044] S2: Add a preset proportion of titanium niobate powder, organic polymer material, solid electrolyte particles and conductive carbon black into N-methylpyrrolidone solvent and mix them to obtain a second slurry, apply the second slurry on both sides of the collector formed by copper foil, and then dry and roll-press to obtain a titanium niobate negative electrode sheet.

[0045] S3: A double-layer PE (polyethylene) material coated with aluminum oxide of appropriate thickness is used as a diaphragm. Preferably, the thickness of the diaphragm is 16 μm.

[0046] S4: The lithium nickel manganese oxide positive electrode sheet, the titanium niobate negative electrode sheet, the separator and the electrolyte are made into a titanium niobate battery, and then the battery is formed and divided into different volumes. The electrolyte of this embodiment is a 1 mol / L concentration of LiPF 6 The solvents propylene carbonate, ethyl methyl carbonate and diethyl carbonate are mixed in a volume ratio of 1:1:1.

[0047] Embodiment 3

[0048] Based on the above embodiment, this embodiment also provides a power system device for a fuel cell vehicle, such as Figure 2 As shown, the power system device includes a fuel cell, a motor and the titanium niobate battery of embodiment 1, wherein the fuel cell and the titanium niobate battery can supply power to the motor, and the fuel cell can supply power to the titanium niobate battery.

[0049] In this embodiment, the calling method of the power system device includes:

[0050] Starting the fuel cell vehicle, obtaining the current power of the titanium niobate battery, when the power of the titanium niobate battery is greater than a preset first power, prohibiting the starting of the fuel cell, and starting the titanium niobate battery at the same time; when the power of the titanium niobate battery is less than a preset second power, starting the fuel cell, and the fuel cell charges the titanium niobate battery; when the power of the titanium niobate battery is at a preset third power, prohibiting the fuel cell from charging the titanium niobate battery;

[0051] When the output power of the fuel cell is less than the requested power of the vehicle, the titanium niobate battery is started.

[0052] Preferably, the first power level ranges from 80% to 100% of the maximum power of the titanium niobate battery, the second power level ranges from 0% to 30% of the maximum power of the titanium niobate battery, and the third power level ranges from 30% to 80% of the maximum power of the titanium niobate battery.

[0053] The power system device of this embodiment makes full use of the advantages of titanium niobate batteries, can reduce the price of the power system of fuel cell vehicles, improve the performance of the power system, and ensure the safety of fuel cell vehicles. Among them, the titanium niobate battery and the fuel cell can supply power to the motor, the fuel cell can supply power to the titanium niobate battery, and the motor energy of the fuel cell vehicle during braking can be recovered by the titanium niobate battery.

[0054] Specifically, during the startup of the fuel cell vehicle, when the power of the titanium niobate battery is greater than the preset first power, the fuel cell is prohibited from starting, and the titanium niobate battery is started. This step is to protect the titanium niobate battery as a whole from being overcharged (overcharged). In the process of judging the power, the power of the titanium niobate battery can be judged by detecting the voltage of the titanium niobate battery. Unlike other batteries, which require the voltage of each battery to be detected to prevent the safety of overcharging of a single battery, the high safety of the titanium niobate battery makes it possible to simplify the detection system. Even in the case of slight overcharging, the titanium niobate battery does not have a significant impact on the safety of the battery. At the same time, most of the power of the titanium niobate battery is collected through recycling and braking. During the use of the vehicle, especially in crowded urban roads where frequent braking and deceleration are required, the energy absorbed by the titanium niobate battery during the vehicle braking process can further reduce the energy consumption of the fuel cell vehicle.

[0055] When the power of the titanium niobate battery is less than the set second power, the fuel cell is started and the fuel cell charges the titanium niobate battery. When the power of the titanium niobate battery is low, the fuel cell can be used to charge the titanium niobate battery to ensure the high rate capability of the battery system to ensure that the vehicle has suitable acceleration performance.

[0056] When the power of the titanium niobate battery is at the preset third power level, the fuel cell is prohibited from charging the titanium niobate battery. While ensuring that the titanium niobate battery has sufficient power to meet the vehicle's high-rate requirements, the power system device prevents the fuel cell from charging more power to the titanium niobate battery, thereby ensuring that more power of the titanium niobate battery is provided by energy collection during braking, thereby reducing the overall energy consumption of the vehicle during driving.

[0057] When the output power of the fuel cell is less than the requested power of the vehicle, the titanium niobate battery is activated. This means that when the output power of the fuel cell cannot meet the needs of the vehicle, the titanium niobate battery is activated to increase the overall output power of the vehicle and increase the power of the titanium niobate battery.

[0058] In addition, another embodiment of the present invention further provides a power battery overcharge protection device, the device comprising:

[0059] The acquisition module is used to obtain the voltage value of the titanium niobate battery in the fuel cell vehicle and convert the voltage value into a power value, the output power of the fuel cell and the requested power of the whole vehicle.

[0060] A judgment module, used to judge the comparison between the power of the titanium niobate battery and the preset first power, second power and third power values, and to judge the output power of the fuel cell and the power requested by the whole vehicle;

[0061] A control module is used to control the charging and starting of the titanium niobate battery.

[0062] The preparation method of the titanium niobate battery provided by the present invention is specifically described below through several specific examples.

[0063] Example 1:

[0064] The preparation method of the titanium niobate battery of this example includes the following steps:

[0065] (1) The spinel lithium nickel composite oxide (LiNi 0.5 Mn 1.5 O 4 ) powder, acetylene black and polyvinylidene fluoride (PVDF) and LATP (Li 1+x Al x Ti 2-x (PO 4 ) 3 The first slurry was added to an N-methylpyrrolidone (NMP) solvent in a weight ratio of 93:3:2:2 and mixed to obtain a first slurry. The first slurry was applied to both sides of a collector formed of an aluminum foil with a thickness of 12 μm, and dried in a constant temperature oven at 120° C. and rolled to obtain a lithium nickel manganese oxide positive electrode sheet.

[0066] (2) Titanium niobate powder, PEO, LLZO (Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 ), Super P, and polyvinylidene fluoride (PVDF) were added to NMP solvent in a mass ratio of 92:2:2:2:2 and mixed to obtain a second slurry. The second slurry was applied to both sides of a collector formed of a copper foil with a thickness of 8 μm, and dried in a constant temperature vacuum oven at 80°C and rolled to obtain a titanium niobate negative electrode sheet.

[0067] (3) A 16 μm double-layer aluminum oxide-coated PE was used as the separator. A 1 mol / L concentration of LiPF 6 A mixed system of solvents propylene carbonate (PC), ethyl methyl carbonate and diethyl carbonate (DEC) in a volume ratio of 1:1:1 was used as the electrolyte.

[0068] (4) The above-mentioned lithium nickel manganese oxide positive electrode sheet, titanium niobate negative electrode sheet, separator and electrolyte are made into a 2Ah titanium niobate battery, and then formed and divided into different capacities.

[0069] Example 2:

[0070] Compared with Example 1, the process of preparing the titanium niobate negative electrode sheet in Example 2 is changed to:

[0071] Titanium niobate powder, PAN, Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO), Super P and polyvinylidene fluoride (PVdF) were added to NMP solvent at a mass ratio of 92:2:2:2:2 and mixed, and then the mixed slurry was coated on both sides of a collector formed of a copper foil with a thickness of 8 μm, and dried in a constant temperature vacuum oven at 80°C and rolled to obtain a titanium niobate negative electrode sheet. The other steps were the same as in Example 1.

[0072] Example 3:

[0073] Compared with Example 1, the process of preparing the titanium niobate negative electrode sheet in Example 3 becomes:

[0074] Titanium niobate powder, PAN, LiFSI, Li 6.4 La 3 Zr 1.4 Ta 0.6 O 12(LLZTO), Super P and polyvinylidene fluoride (PVdF) were added to NMP solvent at a mass ratio of 92:2:1:1:2:2 and mixed. Subsequently, the mixed slurry was coated on both sides of a collector formed of a copper foil with a thickness of 8 μm, and dried in a constant temperature vacuum oven at 80°C and rolled to obtain a titanium niobate negative electrode sheet. The other steps were the same as in Example 1.

[0075] Example 4:

[0076] Compared with Example 1, the process of the titanium niobate negative electrode sheet in this example becomes:

[0077] Titanium niobate powder, Super P and polyvinylidene fluoride (PVdF) were added to NMP solvent at a mass ratio of 92:4:4 and mixed to obtain a negative electrode layer slurry. 6.4 La 3 Zr 1.4 Ta 0.6 O 12 (LLZTO) was added to N-methylpyrrolidone (NMP) at a mass ratio of 2:1:1 and mixed to obtain a coating layer slurry. The negative electrode slurry was applied to both sides of a collector formed of a copper foil with a thickness of 8 μm to form a negative electrode layer, and then the coating layer slurry was applied to both sides of the negative electrode layer to form a coating layer, and then dried in a constant temperature vacuum oven at 80°C and rolled to obtain a titanium niobate negative electrode sheet. The other steps were the same as Example 1.

[0078] Comparative Example 1: Compared with Example 1, the second step in Comparative Example 1 becomes:

[0079] Titanium niobate powder, Super P and polyvinylidene fluoride (PVdF) were added to NMP solvent at a mass ratio of 92:4:4 and mixed to obtain a slurry. The slurry was applied to both sides of a current collector formed of a copper foil with a thickness of 8 μm, and dried in a constant temperature vacuum oven at 60°C and rolled to obtain a negative electrode. The other steps were the same as in Example 1.

[0080] Titanium niobate battery test:

[0081] The titanium niobate battery obtained above was subjected to performance tests, including the following performance tests:

[0082] (1) 45℃ 2C / 2C battery cycle test

[0083] First, the lithium-ion battery was allowed to stand at 45°C for 30 minutes, discharged at a constant current of 2C to 1.5V, and then allowed to stand for 5 minutes; then charged to 3.6V at a constant current of 2C, further charged at a constant voltage of 3.6V to a current of 0.1C, allowed to stand for 5 minutes, and then discharged to 1.5V at a constant current of 2C. This is a charge and discharge cycle process, and the discharge capacity obtained is the discharge capacity Ca of the lithium-ion battery. After that, 300 charge and discharge cycles were performed, and the discharge capacity of the 300th cycle was recorded as Cb.

[0084] Capacity retention rate of lithium-ion battery after 300 cycles (%) = Cb / Ca;

[0085] The performance test data of the titanium niobate batteries of the embodiments of the present invention and the comparative examples are shown in Table 1.

[0086] Table 1: Titanium niobate battery performance test results

[0087] Group 45℃ cycle capacity retention rate Example 1 72.0％ Example 2 73.9％ Example 3 79.7％ Example 4 80.6％ Comparative Example 1 59.0％

[0088] According to the test results of titanium niobate batteries, after adding at least two of organic polymer materials, new lithium salts and solid electrolyte particles to the negative electrode, the performance of titanium niobate batteries has been significantly improved, whether in the form of a blend with the negative electrode material or as a coating layer alone. It is speculated that the addition can not only increase the lithium ion transmission rate at the negative electrode interface and improve the rate performance, but also act as an interface membrane to inhibit the occurrence of interface side reactions and the positive and negative electrode shuttle effect, which comprehensively improves the performance of titanium niobate batteries.

[0089] The present invention provides a titanium niobate battery and a preparation method thereof, applies the titanium niobate battery to hydrogen fuel vehicles and discloses a method for using the titanium niobate battery in hydrogen fuel vehicles, that is, a power system device including the titanium niobate battery is used, which is different from the existing device, wherein a new type of titanium niobate battery module is used, and the shuttle effect of the side reaction products of nickel manganese oxide under high voltage on the negative electrode is solved through the innovative design of the negative electrode plate, and the titanium niobate negative electrode is protected by the ion-conducting layer on the surface of the negative electrode material, on the one hand, it is protected from the attack of the positive electrode oxidation product, and on the other hand, the surface stability of the negative electrode itself is increased, solving the key problem of the industrialization of nickel manganese titanium niobate battery. By introducing the titanium niobate battery into the vehicle, the control system and hardware system of the vehicle can be greatly simplified, especially in the past, hydrogen fuel vehicles need to carry out redundant control system design and hardware design for safety needs, and introducing the titanium niobate battery into the vehicle will increase the power performance of the vehicle and reduce the cost of the vehicle. This is all due to the high safety, long life and high rate of titanium niobate batteries. The present invention also provides a method for calling the titanium niobate battery in a fuel vehicle, which can ensure better performance of the vehicle and greatly save the power consumption of hydrogen fuel vehicles.

[0090] In the several embodiments provided by the present invention, it should be understood that the apparatus and method disclosed by the present invention can be implemented in other ways. For example, the apparatus embodiments described above are only illustrative, for example, the division of the modules is only a logical function division, and there may be other division methods in actual implementation, for example, multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0091] In addition, each functional module in each embodiment of the present invention may be integrated into one processing module, or each module may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of hardware plus software functional modules.

[0092] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A titanium niobate battery, characterized in that: It includes a titanium niobate negative electrode sheet, a lithium nickel manganese oxide positive electrode sheet, and an electrolyte arranged between the titanium niobate negative electrode sheet and the lithium nickel manganese oxide positive electrode sheet, wherein: The lithium nickel manganese oxide positive electrode plate comprises at least two of an organic polymer material, a novel lithium salt and solid electrolyte particles and a lithium nickel manganese oxide positive electrode material, wherein the lithium nickel manganese oxide positive electrode material accounts for 70-98% by weight; The titanium niobate negative electrode plate comprises an organic polymer material, at least two of a novel lithium salt and solid electrolyte particles and a titanium niobate negative electrode material, wherein the mass ratio of the titanium niobate negative electrode material is 70-98%.

2. The titanium niobate battery according to claim 1, characterized in that: The titanium niobate negative electrode material includes TiNb2O7, Ti2Nb 10 O 29 or Ti2Nb 24 O 62 Any material containing niobium, titanium and oxygen; the lithium nickel manganese oxide positive electrode material includes any material containing manganese and nickel in the form of spinel lithium nickel manganese oxide.

3. The titanium niobate battery according to claim 1, characterized in that: The organic polymer material includes any one of polyacrylonitrile, polyethylene oxide, polyvinylidene fluoride and polymethyl methacrylate.

4. The titanium niobate battery according to claim 1, characterized in that: The novel lithium salt includes any one of LFSI or LTFSI.

5. The titanium niobate battery according to claim 1, characterized in that: The solid electrolyte particles include an inorganic compound with a perovskite structure, an inorganic compound with a LISICON structure, and a Li with a NASICON skeleton structure. 1+x Al x Ti 2-x (PO4)3、Li 3.6 Si 0.6 PO4, amorphous Li 2.9 PO 3.3 N 0.46 , lithium calcium zirconium oxide, lithium lanthanum zirconium oxide with garnet structure Li7La3Zr2O 12 and at least one of its coated and doped derivatives, wherein 0.1≤x≤0.

4.

6. The titanium niobate battery according to claim 1, characterized in that: The charging cut-off voltage range of the titanium niobate battery is 3.3-3.9V, the discharging cut-off voltage range is 1-2.5V, and the rated voltage is 2.6-3.3V.

7. A method for preparing a titanium niobate battery, characterized in that: For preparing the titanium niobate battery according to any one of claims 1 to 6, the preparation method comprises: S1: adding a preset ratio of lithium nickel manganese oxide positive electrode material, conductive carbon black, solid electrolyte particles and organic polymer material into an N-methylpyrrolidone solvent and mixing them to obtain a first slurry, coating the first slurry on both sides of a collector formed of an aluminum foil, and then drying and rolling to obtain a lithium nickel manganese oxide positive electrode sheet; S2: adding a preset ratio of titanium niobate powder, organic polymer material, solid electrolyte particles and conductive carbon black into an N-methylpyrrolidone solvent and mixing them to obtain a second slurry, coating the second slurry on both sides of a collector formed of a copper foil, and then drying and rolling to obtain a titanium niobate negative electrode sheet; S3: using a double-layer polyethylene material coated with aluminum oxide of appropriate thickness as the diaphragm; S4: The lithium nickel manganese oxide positive electrode sheet, the titanium niobate negative electrode sheet, the separator and the electrolyte are used to make a titanium niobate battery.

8. The method for preparing a titanium niobate battery according to claim 7, characterized in that: The electrolyte is formed by mixing solvents of propylene carbonate, ethyl methyl carbonate and diethyl carbonate in a volume ratio of 1:1:1 containing 1 mol / L LiPF6.

9. A power system device for a fuel cell vehicle, characterized in that: The invention comprises a fuel cell, a motor and a titanium niobate battery according to any one of claims 1 to 6, wherein: The fuel cell and the titanium niobate battery can supply power to the motor, and the fuel cell can supply power to the titanium niobate battery.

10. The power system device according to claim 9, characterized in that: The calling method of the power system device includes: Starting the fuel cell vehicle, obtaining the current power of the titanium niobate battery, when the power of the titanium niobate battery is greater than a preset first power, prohibiting the starting of the fuel cell, and starting the titanium niobate battery at the same time; when the power of the titanium niobate battery is less than a preset second power, starting the fuel cell, and charging the titanium niobate battery by the fuel cell; when the power of the titanium niobate battery is at a preset third power, prohibiting the fuel cell from charging the titanium niobate battery; When the output power of the fuel cell is less than the requested power of the vehicle, the titanium niobate battery is started.

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