High-b-value linear ntc thermistor material with good batch consistency, preparation method thereof and thermistor element

Abstract

The application provides a high-B-value linear NTC thermistor material with good batch consistency, a preparation method thereof and a thermistor element, relates to the technical field of NTC thermistor materials, and is characterized in that a NiO-ZnO binary oxide system is selected, ZnO is used as a main crystal phase, the conductive behavior and resistance-temperature characteristics of the material are controlled through a small amount of NiO, a NiO-ZnO linear NTC thermistor material directly physically compounded by NiO and ZnO is formed, the system composition is more simplified, the composite path is shorter, the phase composition is more easily controlled, the composition fluctuation and the organization non-uniformity caused by the complex second phase generation process, the insufficient local reaction or the uneven phase distribution can be reduced, and therefore the performance dispersion between different batches is reduced, and the consistency and the repeatability of the material preparation are improved.

Description

Technical Field

[0001] This invention belongs to the field of NTC thermistor material technology, and specifically relates to a high-B-value linear NTC thermistor material with good batch-to-batch consistency, its preparation method, and the thermistor element. Background Technology

[0002] Negative temperature coefficient (NTC) thermistors have wide applications in temperature compensation, surge suppression, and infrared detection. With the advancement of science and society, the requirements for electrical components in daily life are gradually increasing. The resistivity of conventional nonlinear thermistors is an exponential function of temperature, requiring circuit design to achieve linear output. This not only increases the complexity of the circuit but also reduces the accuracy of the sensor, thus limiting the application of the material. Existing research focuses primarily on nonlinear NTC thermistors, with limited research on linear NTC thermistors. Linear NTC thermistors, however, enable linear output of circuit signals, greatly simplifying the circuit. Therefore, researching a linear thermistor material is of great significance for improving the accuracy of electronic components and expanding their application areas.

[0003] Among the reported linear NTC thermistors, Chinese invention patent application CN202311238841.1 discloses a linear NTC thermistor material LaMnO3-Al2O3. This material has LaMnO3 as the main crystalline phase, and its electrical properties are adjusted by doping 10-30% Al2O3 into LaMnO3. The resulting LaMnO3-Al2O3 exhibits linear resistance-temperature characteristics in the range of 30℃ to 65℃. Chinese invention patent application CN202311236250.0 discloses a linear NTC thermistor material CdSnO3-Al2O3. This material has CdSnO3 as the main crystalline phase, and its electrical properties are adjusted by doping 10-30% Al2O3 into CdSnO3. Al2O3 exhibits linear resistance-temperature characteristics in the temperature range of 25℃ to 175℃. The technical solution disclosed in Chinese invention patent application number CN202410567026.8 is a linear NTC thermistor material Al2O3-ZnO and its preparation method. ZnO is used as the main crystal phase, and Al2O3 with a molar fraction of 5% to 15% is doped into it to form a new spinel (ZnAl2O4) material through reaction, thereby changing the overall electrical properties of the material.

[0004] The aforementioned linear NTC thermistor materials generally employ oxides containing two transition metal elements, with spinel-type structures as the main crystalline phase. However, due to the high volatility of these transition metal oxides, component volatilization easily occurs during the sintering process, leading to deviations in the final product composition from the designed ratio, making it difficult to guarantee batch-to-batch consistency and repeatability. Summary of the Invention

[0005] In view of this, and to address the above shortcomings, it is necessary to provide a high-B-value linear NTC thermistor material with good batch-to-batch consistency.

[0006] It is also necessary to provide a method for preparing high-B-value linear NTC thermistor materials with good batch-to-batch consistency.

[0007] It is also necessary to provide a thermistor element.

[0008] The technical solution adopted by this invention to solve its technical problem is:

[0009] A method for preparing a high-B-value linear NTC thermistor material with good batch-to-batch consistency includes the following steps:

[0010] S1: Nickel oxide powder and zinc oxide powder are mixed to obtain a mixed powder. The mixed powder is pretreated to improve the powder activity and obtain a precursor powder.

[0011] S2: Polyvinyl alcohol is added to the precursor powder and mixed. After the mixture is uniform, the powder is pressed by molding and cold isostatic pressing in sequence to make the powder particles in close contact and obtain a block precursor.

[0012] S3: The bulk precursor is placed at a first predetermined temperature for debinding and then naturally cooled; subsequently, the bulk precursor is placed at a second predetermined temperature and sintered for a second predetermined time to create conditions for volume diffusion, thereby densifying the powder and forming a NiO-ZnO linear NTC thermistor material that is a direct physical composite of NiO and ZnO.

[0013] Preferably, in step S1, the molar fraction of the nickel oxide powder accounts for 1% to 3% of the total molar fraction of the zinc oxide powder and the nickel oxide powder.

[0014] Preferably, in step S1, the molar fraction of the nickel oxide powder accounts for 2% of the total molar fraction of the zinc oxide powder and the nickel oxide powder.

[0015] Preferably, in step S1, the preprocessing is as follows:

[0016] A: Add ethanol to the mixed powder and ball mill it to obtain the first ball-milled powder.

[0017] B: The first ball-milled powder is pre-calcined to obtain pre-calcined powder;

[0018] C: Add ethanol to the pre-calcined powder and ball mill again. After ball milling, dry and sieve to obtain the precursor powder.

[0019] Preferably, the pre-firing temperature is 300℃-600℃.

[0020] Preferably, in step S2, the amount of polyvinyl alcohol added accounts for 5%-10% of the total mass of the precursor powder.

[0021] Preferably, in step 2, the pressure of the molding method is 50MPa-100MPa and the holding time is 30s-60s, and the pressure of the cold isostatic pressing method is 200MPa-400MPa and the holding time is 30s-60s.

[0022] Preferably, in step S3, sintering is carried out in an air furnace, the first predetermined temperature is 400℃-550℃, the first predetermined time is 20-40 minutes, the second predetermined temperature is 1100℃-1250℃, and the second predetermined time is 6h-8h.

[0023] A high B-value linear NTC thermistor material is prepared according to the preparation method of the high B-value linear NTC thermistor material with good batch-to-batch consistency as described above.

[0024] A thermistor element comprising, as described above, a high-B-value linear NTC thermistor material as the sensing element.

[0025] The advantages of this invention compared to the prior art are:

[0026] This invention does not employ a design approach using spinel-type or perovskite-type composite oxides as the main crystalline phase. Instead, it selects a NiO-ZnO binary oxide system with ZnO as the main crystalline phase. By using a small amount of NiO to regulate the conductivity and temperature resistance characteristics of the material, a NiO-ZnO linear NTC thermistor material with direct physical composite of NiO and ZnO is formed. This simplifies the system composition, shortens the composite path, and makes the phase composition easier to control. It can reduce compositional fluctuations and microstructure inhomogeneities caused by complex second-phase formation processes, insufficient local reactions, or uneven phase distribution. This helps to reduce performance dispersion between different batches and improve the consistency and repeatability of material preparation.

[0027] Secondly, this invention involves mixing nickel oxide powder and zinc oxide powder to obtain a mixed powder, pretreating the mixed powder to obtain a precursor powder, adding polyvinyl alcohol to the precursor powder and mixing them evenly, then pressing the evenly mixed powder using molding and cold isostatic pressing methods to ensure close contact between powder particles, resulting in a block precursor. The block precursor is placed at a first predetermined temperature for debinding and then naturally cooled. Subsequently, the block precursor is placed at a second predetermined temperature and sintered for a second predetermined time to create conditions for volume diffusion, thereby densifying the powder and forming a NiO-ZnO linear NTC thermistor material, which is a direct physical composite of NiO and ZnO. By pretreating the mixed powder and then subjecting the precursor powder to secondary isostatic pressing, the activity of the powder is improved, the bonding between powder particles is tighter, and the powder becomes denser and has better electrical properties during sintering.

[0028] Finally, introducing nickel oxide into the zinc oxide-based system is beneficial for regulating the electrical transport behavior of the material, making the temperature resistance response of the material more obvious, and thus helping to obtain a higher B value. Attached Figure Description

[0029] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 The image shows a SEM image of the NiO-ZnO ceramic prepared in Example 1, where the large grains are ZnO and the small grains are NiO.

[0031] Figure 2 The image shows a SEM image of the NiO-ZnO ceramic prepared in Example 2, where the large grains are ZnO and the small grains are NiO.

[0032] Figure 3 The image shows a SEM image of the NiO-ZnO ceramic prepared in Example 3, where the large grains are ZnO and the small grains are NiO.

[0033] Figure 4 The image shows a SEM image of the NiO-ZnO ceramic prepared in Comparative Example 1, where the large grains are ZnO and the small grains are NiO.

[0034] Figure 5 The images are XRD patterns of Examples 1-2.

[0035] Figure 6 The image shows the RT curve of the NTC thermistor material prepared in Example 1.

[0036] Figure 7 This is the RT curve of the NTC thermistor material prepared in Example 2.

[0037] Figure 8 This is the RT curve of the NTC thermistor material prepared in Example 3.

[0038] Figure 9 The RT curve of the NTC thermistor material prepared in Comparative Example 1 is shown. Detailed Implementation

[0039] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0040] In a first aspect, the present invention provides a method for preparing a high-B-value linear NTC thermistor material with good batch-to-batch consistency, comprising the following steps:

[0041] S1: Nickel oxide powder and zinc oxide powder are mixed to obtain a mixed powder. The mixed powder is pretreated to improve the powder activity and obtain a precursor powder.

[0042] S2: Polyvinyl alcohol is added to the precursor powder and mixed. After the mixture is uniform, the powder is pressed by molding and cold isostatic pressing in sequence to make the powder particles in close contact and obtain a block precursor.

[0043] S3: The bulk precursor is placed at a first predetermined temperature for debinding and then naturally cooled; subsequently, the bulk precursor is placed at a second predetermined temperature and sintered for a second predetermined time to create conditions for volume diffusion, thereby densifying the powder and forming a NiO-ZnO linear NTC thermistor material that is a direct physical composite of NiO and ZnO.

[0044] This invention, through the above method, ensures the relative stability of the phase composition of the ZnO-based system, the controllability of the sintering process, and the uniformity of the material microstructure. It introduces NiO with a large difference in B value, which matches the matrix ionic radius, valence state characteristics, solid solution behavior, second phase formation tendency, grain boundary distribution state, and phase evolution behavior during the sintering process. This allows NiO to effectively regulate the ZnO system, thereby achieving synergistic adjustment of the material's room temperature resistivity and B value, while maintaining good linearity, stability, and repeatability.

[0045] If the above factors are not matched, even if the doping component differs significantly from ZnO in terms of resistivity or B value, a stable and controllable adjustment effect may not be achieved. For example, some oxides with significantly different electrical parameters from ZnO may, upon introduction, form second phases such as spinel or perovskite due to complex reaction pathways, or form unevenly distributed local phase compositions at grain boundaries, leading to inhomogeneous material structure and affecting batch-to-batch consistency, repeatability, and electrical performance stability. In contrast, this invention uses a direct composite of NiO and ZnO, resulting in a simpler system composition. This reduces local compositional fluctuations and structural inhomogeneities caused by the formation of complex second phases, facilitating effective adjustment of the overall electrical properties of the material. Simultaneously, the introduction of NiO helps regulate the electrical transport behavior of the ZnO-based system, thereby contributing to a more pronounced thermosensitive response and a higher B value.

[0046] In this invention, the heterogeneous interface of the NiO-ZnO composite material, formed by combining NiO and ZnO, is one of the key reasons for the linearization of the material. After NiO and ZnO come into contact, a space charge region and an interface barrier are formed at the interface. Charge carriers must overcome this barrier during transport, thus significantly regulating the overall electrical transport behavior of the material. Compared to a single ZnO system, the introduction of the NiO-ZnO heterogeneous interface means that the total resistance of the material is jointly determined by the bulk phase, grain boundaries, and the heterogeneous interface. This helps reduce the nonlinear deviation caused by changes in the conductivity mechanism at different temperatures, resulting in a smoother resistance variation trend over a wider temperature range. Furthermore, the introduction of NiO alters the defect state and local charge distribution near the interface, thereby affecting the interface barrier height and the thermal activation process of charge carriers, ultimately improving the RT linearity of the material.

[0047] Furthermore, in S1, the molar fraction of the nickel oxide powder accounts for 1% to 3% of the total molar fraction of the zinc oxide powder and the nickel oxide powder, so as to ensure that the amount of NiO introduced does not affect the ZnO main crystalline phase, but has a significant regulating effect on the overall electrical properties of the material.

[0048] Variations in NiO content affect the compositional distribution, defect state, and grain boundary characteristics of ZnO-based systems, thereby influencing carrier transport behavior and consequently altering the room-temperature resistivity and B-value of the material. At low NiO contents, the regulatory effect is insufficient; further increases in NiO content may lead to excessive changes in system composition or interface state, hindering the attainment of stable and controllable electrical properties.

[0049] Specifically, before weighing nickel oxide powder and zinc oxide powder, both need to be dried and then weighed to ensure accurate mixing.

[0050] Furthermore, in S1, the molar fraction of the nickel oxide powder accounts for 2% of the total molar fraction of the zinc oxide powder and the nickel oxide powder.

[0051] Furthermore, in S1, the preprocessing is as follows:

[0052] A: Add ethanol to the mixed powder and ball mill it to obtain the first ball-milled powder.

[0053] B: The first ball-milled powder is pre-calcined to obtain pre-calcined powder;

[0054] C: Add ethanol to the pre-calcined powder and ball mill again. After ball milling, dry and sieve to obtain the precursor powder.

[0055] Specifically, the ball milling is performed at 400 rpm for 4-6 hours, and the mass ratio of ethanol to the mixed powder or pre-calcined powder is 3:1.

[0056] Furthermore, the pre-firing temperature is 300℃-600℃, preferably 400℃.

[0057] Furthermore, in step S2, the amount of polyvinyl alcohol (PVA) added accounts for 5%-10% of the total mass of the precursor powder.

[0058] Furthermore, in step 2, the pressure of the molding method is 50MPa-100MPa and the holding time is 30s-60s, while the pressure of the cold isostatic pressing method is 200MPa-400MPa and the holding time is 30s-60s.

[0059] Furthermore, in step S3, sintering is carried out in an air furnace, with the temperature increased at a rate of 1°C / min to a first predetermined temperature, which is 400°C-550°C, and the first predetermined time is 20-40 minutes, in order to achieve the purpose of removing the binder. Then, the furnace is cooled to room temperature, and the temperature is rapidly increased at a rate of 10°C / min to a second predetermined temperature, which is 1100°C-1250°C, and the second predetermined time is 6-8 hours.

[0060] A high B-value linear NTC thermistor material is prepared according to the preparation method of the high B-value linear NTC thermistor material with good batch-to-batch consistency as described above.

[0061] A thermistor element comprising, as described above, a high-B-value linear NTC thermistor material as the sensing element.

[0062] The following examples demonstrate the preparation process of high-B-value linear NTC thermistor materials with good batch-to-batch consistency.

[0063] Example 1:

[0064] (1) Dry the raw material (metal oxide powder), and then weigh a total of 10.1873g of metal oxide powder, including 0.1873g of NiO (accounting for 2% of the total molar amount of metal oxide powder) and 10g of ZnO. Put the weighed metal oxide powder into a ball mill jar, add 20g of grinding beads and 50mL of ethanol, and mill the ball mill jar at 400rpm for 4h in a planetary ball mill to obtain the first ball milled powder. Then, heat the first ball milled powder to 400℃ at a heating rate of 5℃ for 2-3h to obtain the pre-calcined powder. Put the pre-calcined powder into a ball mill jar, add 120g of grinding beads and 100mL of ethanol, and mill the ball mill jar at 400rpm for 4h in a planetary ball mill. After ball milling, place the obtained product in a 70℃ oven to dry, and sieve it with a 200-mesh stainless steel sieve to obtain the precursor powder.

[0065] (2) Weigh 5% of the total mass of the precursor powder and add the PVA solution to the precursor powder. Press the powdered precursor by molding method with a pressure of 80 MPa and hold for 30 s. Then press it by cold isostatic pressing with a pressure of 200 MPa and hold for 30 s to obtain a block precursor with a diameter of 12 mm.

[0066] (3) The block precursor was placed in an air furnace for high-temperature sintering. During sintering, the temperature was first raised to 500°C at a heating rate of 1°C / min and held for 20 min. Then, the temperature was rapidly raised to 1100°C at a heating rate of 10°C / min and held for 8 h. The material was then cooled to room temperature with the furnace to obtain NiO-ZnO linear NTC thermistor material, named NZ-1.

[0067] Example 2

[0068] (1) Dry the raw material (metal oxide powder), and then weigh a total of 10.2838 g of metal oxide powder, including 0.2838 g of NiO (accounting for 3% of the total molar amount of metal oxide powder) and 10 g of ZnO. Put the weighed metal oxide powder into a ball mill jar, add 20 g of grinding beads and 50 mL of ethanol, and mill the ball mill jar at 400 rpm for 4 h in a planetary ball mill to obtain the first ball milled powder. Then, heat the first ball milled powder to 400 ℃ at a heating rate of 5 ℃ and pre-calcine it for 2-3 h to obtain the pre-calcineed powder. Put the pre-calcineed powder into a ball mill jar, add 20 g of grinding beads and 50 mL of ethanol, and mill the ball mill jar at 400 rpm for 4 h in a planetary ball mill. After ball milling, place the obtained product in a 70 ℃ oven to dry, and sieve it with a 200 mesh stainless steel sieve to obtain the precursor powder.

[0069] (2) Weigh 5% of the total mass of the precursor powder and add the PVA solution to the precursor powder. Press the powdered precursor by molding method with a pressure of 80 MPa and hold for 30 s. Then press it by cold isostatic pressing with a pressure of 200 MPa and hold for 30 s to obtain a block precursor with a diameter of 12 mm.

[0070] (3) The block precursor was placed in an air furnace for high-temperature sintering. During sintering, the temperature was first raised to 500°C at a heating rate of 1°C / min and held for 20 min. Then, the temperature was rapidly raised to 1100°C at a heating rate of 10°C / min and held for 8 h. The material was then cooled to room temperature with the furnace to obtain NiO-ZnO linear NTC thermistor material, named NZ-2.

[0071] Example 3

[0072] (1) Dry the raw material (metal oxide powder), and then weigh a total of 10.0927g of metal oxide powder, including 0.0927g of NiO (accounting for 1% of the total molar number of metal oxide powder) and 10g of ZnO. Put the weighed metal oxide powder into a ball mill jar, add 20g of grinding beads and 50mL of ethanol, and grind the ball mill jar at 400rpm for 4h in a planetary ball mill to obtain the first ball milled powder. Then, heat the first ball milled powder to 400℃ at a heating rate of 5℃ for 2-3h to obtain the pre-calcined powder. Put the pre-calcined powder into a ball mill jar, add 20g of grinding beads and 50mL of ethanol, and grind the ball mill jar at 400rpm for 4h in a planetary ball mill. After ball milling, place the obtained product in a 70℃ oven to dry, and sieve it with a 200-mesh stainless steel sieve to obtain the precursor powder.

[0073] (2) Weigh 5% of the total mass of the precursor powder and add the PVA solution to the precursor powder. Press the powdered precursor by molding method with a pressure of 80 MPa and hold for 30 s. Then press it by cold isostatic pressing with a pressure of 200 MPa and hold for 30 s to obtain a block precursor with a diameter of 12 mm.

[0074] (3) The block precursor was placed in an air furnace for high-temperature sintering. During sintering, the temperature was first raised to 500°C at a heating rate of 1°C / min and held for 20 min. Then, the temperature was rapidly raised to 1100°C at a heating rate of 10°C / min and held for 8 h. The material was then cooled to room temperature with the furnace to obtain NiO-ZnO linear NTC thermistor material, named NZ-3.

[0075] Comparative Example 1 (without preheating)

[0076] (1) Dry the raw material (metal oxide powder), and then weigh a total of 10.1873 g of metal oxide powder, including 0.1873 g of NiO (accounting for 2% of the total molar amount of metal oxide powder) and 10 g of ZnO. Put the weighed metal oxide powder into a ball mill jar, add 20 g of grinding beads and 50 mL of ethanol, and mill the ball mill jar at 400 rpm for 4 h in a planetary ball mill. After milling, place the obtained product in a 70℃ oven to dry, and sieve it through a 200 mesh stainless steel sieve to obtain the precursor powder.

[0077] The other steps are the same as in Example 1, and a NiO-ZnO linear NTC thermistor material is obtained, named NZ-4.

[0078] The NZ-1, NZ-2, NZ-3, and NZ-4 samples prepared in Examples 1-3 and Comparative Example 1 were examined using scanning electron microscopy (SEM), and the SEM images are shown below. Figure 1-4 As shown, the large grains are ZnO and the small grains are NiO.

[0079] The NZ-1 and NZ-2 samples prepared in Examples 1-2 were subjected to XRD analysis, and the XRD patterns are shown below. Figure 5 As shown.

[0080] Silver paste was applied to both sides of the NZ-1, NZ-2, NZ-3, and NZ-4 samples prepared in Examples 1-3 and Comparative Example 1 to form electrodes. The resistance-temperature relationship of these electrodes was measured using a four-probe measurement system to obtain the RT curves (RT curves are one of the important parameters describing the electrical properties of thermistor materials) for each group of NTC thermistor materials. Figure 6-9 As shown.

[0081] Depend on Figure 1-4 and Figure 5 It is known that the present invention has produced a dense composite, and the composite consists of only two phases, ZnO and NiO (no reaction has occurred).

[0082] Depend on Figure 6-9 It can be seen that the NiO-ZnO composite prepared in Example 1 exhibits good linearity R in the temperature range of 23℃ to 153℃. 2 =0.997, material constant B=3141K, the NiO-ZnO composite prepared in Example 2 exhibits good linearity R in the temperature range of 20℃~140℃. 2 =0.999, material constant B=2734K, linearity of Example 3 is R 2 =0.996, material constant B=2869K. Comparative Example 1: Linearity R 2=0.922, material constant B=2339K. Examples 1-3 show that NiO doping with a molar fraction of 1%–3% helps to obtain better resistance-temperature linearity characteristics. Specifically, the test results of Example 1 show that, under appropriate NiO content and sintering process conditions, a balance between linear response and a high B value can be achieved. Examples 1 and Comparative Example 1 demonstrate that pretreatment of the mixed powder (ball milling-pre-sintering-ball milling) helps to improve powder activity, linearity, B value, and electrical properties.

[0083] Compared to the prior art patent 202410567026.8, the present invention uses less doped raw material (nickel oxide) and has a larger B value (in the prior art). Figure 1 At temperatures between 160℃ and 210℃, resistivity decreases rapidly. Figure 2 (The resistivity decreases rapidly in the 120℃-180℃ range, while the resistance decreases slowly, resulting in a small B value). Meanwhile, the existing patent 202410567026.8 clearly confirms that a reaction occurred in the existing patent, forming a three-dimensional conductive composite material of ZnAl2O4 and ZnO. In contrast, this invention is merely a binary composite material of nickel oxide and zinc oxide (without a reaction). Therefore, the system of this invention is simpler, the phase is more uniform, and the amount of doped elements added is lower, resulting in better linearity, stability, and repeatability, and a larger B value.

[0084] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. Those skilled in the art will understand that implementing all or part of the above-described embodiments and making equivalent changes in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A method for preparing a high-B-value linear NTC thermistor material with good batch-to-batch consistency, characterized in that, Includes the following steps: S1: Nickel oxide powder and zinc oxide powder are mixed to obtain a mixed powder. The mixed powder is pretreated to improve the powder activity and obtain a precursor powder. S2: Polyvinyl alcohol is added to the precursor powder and mixed. After the mixture is uniform, the powder is pressed by molding and cold isostatic pressing in sequence to make the powder particles in close contact and obtain a block precursor. S3: Place the block precursor at a first predetermined temperature for debinding, and then allow it to cool naturally; Subsequently, the bulk precursor is placed at a second predetermined temperature and sintered for a second predetermined time to create conditions for volume diffusion, thereby densifying the powder and forming a NiO-ZnO linear NTC thermistor material that is a direct physical composite of NiO and ZnO.

2. The method for preparing high-B-value linear NTC thermistor material with good batch-to-batch consistency as described in claim 1, characterized in that, In S1, the molar fraction of the nickel oxide powder accounts for 1% to 3% of the total molar fraction of the zinc oxide powder and the nickel oxide powder.

3. The method for preparing high-B-value linear NTC thermistor material with good batch-to-batch consistency as described in claim 2, characterized in that, In S1, the molar fraction of the nickel oxide powder accounts for 2% of the total molar fraction of the zinc oxide powder and the nickel oxide powder.

4. The method for preparing high-B-value linear NTC thermistor material with good batch-to-batch consistency as described in claim 1, characterized in that, In S1, the preprocessing is as follows: A: Add ethanol to the mixed powder and ball mill it to obtain the first ball-milled powder. B: The first ball-milled powder is pre-calcined to obtain pre-calcined powder; C: Add ethanol to the pre-calcined powder and ball mill again. After ball milling, dry and sieve to obtain the precursor powder.

5. The method for preparing high-B-value linear NTC thermistor material with good batch-to-batch consistency as described in claim 4, characterized in that, The preheating temperature is 300℃-600℃.

6. The method for preparing high-B-value linear NTC thermistor material with good batch-to-batch consistency as described in claim 1, characterized in that, In step S2, the amount of polyvinyl alcohol added accounts for 5%-10% of the total mass of the precursor powder.

7. The method for preparing a high-B-value linear NTC thermistor material with good batch-to-batch consistency as described in claim 2, characterized in that, In step 2, the pressure of the molding method is 50MPa-100MPa and the holding time is 30s-60s, while the pressure of the cold isostatic pressing method is 200MPa-400MPa and the holding time is 30s-60s.

8. The method for preparing high-B-value linear NTC thermistor material with good batch-to-batch consistency as described in claim 1, characterized in that, In step S3, sintering is carried out in an air furnace, with the first predetermined temperature being 400℃-550℃, the first predetermined time being 20-40 minutes, the second predetermined temperature being 1100℃-1250℃, and the second predetermined time being 6h-8h.

9. A high B-value linear NTC thermistor material, characterized in that, The high-B-value linear NTC thermistor material with good batch-to-batch consistency is prepared according to any one of claims 1-8.

10. A thermistor element, characterized in that, It includes the high B-value linear NTC thermistor material as described in claim 9.

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